Magnetic Stimulation Coils and Ferromagnetic Components for Therapeutic and Diagnostic Procedures

Abstract

To provide a system for treating or making a diagnosis on a patient.SOLUTION: An example system may include: an electromagnet including a first conductive winding, a second conductive winding, and a third conductive winding; a drive circuit electrically coupled to the electromagnet; and a controller configured to control the drive circuit to provide current to the electromagnet to generate a pulsing magnetic field. The electromagnet may define an asymmetric figure 8 coil. The first and second conductive windings may define a first loop of the figure 8 coil. The third conductive winding may define a second loop of the figure 8 coil.SELECTED DRAWING: Figure 4A

Description

Technical Field

[0001] The present invention relates to magnetic stimulation coils and ferromagnetic components for therapeutic and diagnostic procedures.

Background Art

[0002] Some diseases can be treated and / or diagnosed through the application of a magnetic field to the affected part of a patient's body. Neurons and muscle cells can be in the form of biological circuits that carry electrical signals and respond to electromagnetic stimulation. When a conductive wire loop is passed through a magnetic field or is in the presence of a changing magnetic field, a current can be induced in the wire. The same principle can apply to conductive biological tissue. When a changing magnetic field is applied to a part of the body, neurons can be depolarized and stimulated. Muscles associated with the stimulated neurons can contract as if the neurons were being activated by their normal causes.

[0003] Nerve cells or neurons can be stimulated in multiple ways, for example, transcutaneously via transcranial magnetic stimulation (TMS). TMS can use rapidly changing magnetic fields to induce a current over neurons without the need to cut or penetrate the skin. For example, depending on the type of nerve, the local pH of the surrounding tissue, and / or peripheral nerve stimulation, a nerve can "fire" when the membrane potential in the nerve rises approximately -90 mV relative to its normal negative ambient level.

[0004] Magnetic stimulation components can be used to create rapidly changing magnetic fields that induce an electric current over nerve cells. Magnetic stimulation components can fail or operate improperly during treatment, which can result in inappropriate treatment for the patient. For example, a magnetic component may appear to be operating correctly, but in fact, it can create magnetic field pulses outside of the designed device specifications, which potentially results in inappropriate diagnosis and / or therapy being administered to the patient. Administering an incorrect magnetic field pulse to a patient can have an adverse effect on the diagnosis and / or treatment of magnetic stimulation. For example, a treatment provider may think that a patient is not responding to treatment when in fact the intended treatment is not being administered to the patient. Thus, the treatment provider and / or diagnosing clinician may be led to make treatment decisions based on incorrect information.

[0005] A typical TMS treatment device generates a pulsed magnetic field that induces an electric current in electrically sensitive cells (e.g., nerve cells or neurons). These induced electric currents typically form a complete circuit within the body such that a zero-current path through the body is created. The electric current induced by a TMS treatment device typically drops to zero approximately in the middle of this path. The rate of this current drop can be slowed, for example, by spreading the current density generated by the TMS device over a wide surface area. However, using this approach can concentrate the return current, which can lead to a higher incidence of undesirable side effects (e.g., stimulation of non-target areas of the subject's brain).

[0006] A typical TMS treatment device may include one or more conductive stimulation coils. Such coils may be composed of a single layer (e.g., wound) and are configured such that the coil can be disposed as close as possible to the tissue to be stimulated. Such coils can stimulate brain tissue at a desired depth relative to the skull. However, such coils are traditionally configured to stimulate only a single location within a subject, and multiple coils (which may be large and difficult to handle) may be required to stimulate multiple locations. SUMMARY OF THE INVENTION

[0007] Methods, systems, and devices for treating or diagnosing a patient are described herein. An exemplary system may include an electromagnet, a drive circuit electrically coupled to the electromagnet, and a controller configured to control the drive circuit to provide a current to the electromagnet to generate a pulsed magnetic field. The electromagnet may include a first conductive winding and a second conductive winding. The first conductive winding may define an inner surface and an outer surface. The outer surface of the first conductive winding may include a convex portion and a concave portion. The second conductive winding may be present proximate to the concave portion of the outer surface of the first conductive winding.

[0008] The first conductive winding may be shaped like a crescent (e.g., shaped like a bow, kidney, or sickle). For example, the outer concave segment of the first conductive winding may define a concave surface, and at least a portion of the second conductive winding may be present within the concave surface of the first conductive winding. Thus, the first conductive winding may not encapsulate (e.g., may not completely surround) the second conductive winding. The first conductive winding may define any shape, such as a non-circular shape or a non-oval shape. The first conductive winding and the second conductive winding may together form a kidney shape. The first conductive winding may include a first number of turns, and the second conductive winding may include a second number of turns, where the first number of turns and the second number of turns may be different.

[0009] The first conductive winding and the second conductive winding can be configured within the housing at a predetermined relative distance from each other, and when the first conductive winding and the second conductive winding are driven, they are adapted to generate at least two independent activation zones in the subject's brain. The activation zone can be a stimulation zone or a sub-stimulation zone. The stimulation zone can include a region of the brain where the induced current exceeds the depolarization threshold of the neurons in the brain. For example, the first stimulation zone can include a current moving in a first direction, and the second stimulation zone can include a current moving in a second direction. The first stimulation zone and the second stimulation zone can be related to two different functional regions of the brain.

[0010] The electromagnet can further include a magnetic core (e.g., one or more ferromagnetic components). The magnetic core can be composed of any combination of a powdered magnetic material, a laminated magnetic material, an amorphous magnetic material, one or more of alloys of iron, nickel, or cobalt, and / or a rare earth element or alloy, such as gadolinium, neodymium, or holmium. For example, the magnetic core can include a single ferromagnetic component defining a first pole defining a substantially circular cross-sectional shape and a second pole defining a crescent-shaped cross-sectional shape. The first pole can define a first pole face, and the second pole can define a second pole face. The first pole face and the second pole face may be non-planar with respect to each other. The magnetic core can include a plurality of ferromagnetic components.

[0011] An exemplary system for treating or diagnosing a patient can include an electromagnet, a drive circuit electrically coupled to the electromagnet, and a controller configured to control the drive circuit to provide a current to the electromagnet to generate a pulsed magnetic field. The electromagnet can include a magnetic core, a first winding, and a second winding. The magnetic core can define a first pole face, a second pole face, and a third pole face, and the third pole face can be present between the first pole face and the second pole face. For example, the three pole faces of the magnetic core can be linearly arranged. Further, the first pole face can be at least partially present within an opening of the first conductive winding, and the second pole face can be at least partially present within an opening of the second conductive winding. Thus, the third pole face can be present between the first conductive winding and the second conductive winding.

[0012] The electromagnet can include a third conductive winding. The third pole face of the magnetic core can be at least partially present within the third conductive winding. The third conductive winding can include more turns than each of the first conductive winding and the second conductive winding. Alternatively, or additionally, the first conductive winding can include more turns than the second conductive winding and / or the third conductive winding. The third conductive winding need not be concentric with the third pole face.

[0013] The electromagnet can include a fourth conductive winding configured to at least partially surround the third conductive winding. Further, the electromagnet can include a return path magnetic core configured to cover at least a portion of the fourth conductive winding. For example, the return path magnetic core can define a channel, and one or more of the third conductive winding and / or the fourth conductive winding can be configured to be at least partially present within the channel of the return path magnetic core. In some examples, the return path magnetic core can include two parts, a first part configured to be present on a first side of the magnetic core and a second part configured to be present on a second side of the magnetic core. The return path magnetic core can have a non-linear shape.

[0014] The magnetic core may define a first pole defining a first pole face, a second pole defining a second pole face, a third pole defining a third pole face, and a fourth pole defining a fourth pole face. The third pole face may be present between the first pole face and the fourth pole face, and the fourth pole face may be present between the third pole face and the second pole face. For example, the first, second, third, and fourth pole faces may be arranged linearly. The third pole may be configured to cover a portion of the upper surface of the first conductive element. Similarly, in some examples, the fourth pole may be configured to cover a portion of the upper surface of the second conductive element.

[0015] The magnetic core may include a plurality of segments, and the plurality of segments are configured to be added or removed to change the shape of each activation zone, the separation of the activation zones, or the relative activation direction. When driven, the first conductive winding and the second conductive winding may circulate current in the same direction (or, for example, in opposite directions). The first conductive winding may include a different number of turns than the second conductive winding. The first conductive winding may be configured to be driven at a different level than the second conductive winding, for example, to modify the shape of the pulsed magnetic field generated by the electromagnet. The electromagnet may include a housing that houses one or more magnetic cores and / or the conductive windings of the electromagnet in a case. The magnetic core may be composed of any combination of a powdered magnetic material, a laminated magnetic material, an amorphous magnetic material, one or more of alloys of iron, nickel, or cobalt, and / or a rare earth element or alloy, such as gadolinium, neodymium, or holmium.

[0016] Another exemplary system for treating or diagnosing a patient can include an electromagnet, a drive circuit electrically coupled to the electromagnet, and a controller configured to control the drive circuit to provide a current to the electromagnet to generate a pulsed magnetic field. The electromagnet can include a first conductive element having a central axis, a second conductive element positioned proximate to the first conductive element and having a central axis, and an external conductive element defining an opening. The first conductive element and the second conductive element may not be disposed within the opening of the external conductive element, but the central axis of the first conductive element and the central axis of the second conductive element may pass through the opening of the external conductive element.

[0017] The first conductive element and the second conductive element can be offset from the central axis of the external conductive element and asymmetrically disposed. For example, the center of the first conductive element can be closer to the external conductive element than the center of the second conductive element. The external conductive element can be a crown coil configured to wrap around the coronal plane of the patient. The magnetic core can include a first pole face and a second pole face, the first pole face being at least partially present within the opening of the first conductive element, and the second pole face being at least partially present within the opening of the second conductive element.

[0018] The first conductive element and the second conductive element may be circular or elliptical in shape and may together form a figure-eight coil. The first conductive element and the second conductive element may together form a B-shaped coil. For example, the first conductive element and the second conductive element may form a non-circular coil. The first and second conductive elements may be of different shapes or sizes. The external conductive element may be electrically connected in series with the first conductive element and the second conductive element. The pulsed magnetic field generated by the electromagnet may be configured to induce a first stimulation zone and a second stimulation zone in the brain of a human subject, and the stimulation zones may include regions of the brain where the induced current exceeds the depolarization threshold of the neurons of the brain. The system may further include a housing that houses the electromagnet in a case.

[0019] Another exemplary system for treating or diagnosing a patient may include an electromagnet, a drive circuit electrically connected to the electromagnet, and a controller configured to control the drive circuit to provide a current to the electromagnet to generate a pulsed magnetic field. The electromagnet may include a first conductive winding, a second conductive winding, and a third conductive winding. The second conductive winding may be at least partially present within the opening of the third conductive winding. For example, the third conductive element may be configured to surround the outer surface of the second conductive element. At least one of the first conductive element and the second conductive element may be in the shape of a "B".

[0020] Also, the electromagnet may include a first magnetic core and a second magnetic core. The first magnetic core may define a first pole face and a second pole face, and the second magnetic core may define a first pole face and a second pole face. The first pole face of the first magnetic core and the first pole face of the second magnetic core may be at least partially present within the opening of the first conductive element. The second pole face of the first magnetic core and the second pole face of the second magnetic core may be at least partially present within the opening of the second conductive element.

Brief Description of the Drawings

[0021]

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DETAILED DESCRIPTION OF THE INVENTION

[0022] In 1831, Michael Faraday discovered that the magnitude of the electric field induced on a conductor is proportional to the rate of change of the magnetic flux cutting across the conductor. Faraday's law (well known to those skilled in the art) can be expressed as E ~ - (A * dB / dt), where E is the induced electric field (volts / meter) and dB / dt is the rate of change of magnetic flux density with time (tesla / second). In other words, the amount of electric field induced in an object such as a conductor can be determined using two factors: the areal density of the magnetic flux and the rate of change with time. The greater the magnetic flux density and its derivative, the greater the induced electric field and the resulting current density. The magnetic flux can be a function of distance. For example, since the magnetic flux density can decrease in intensity as a function of distance from the source of the magnetic field (e.g., 1 / r3 or 1 / r5, etc.), the closer the conductor is to the source of the magnetic field, the greater the magnetic flux density can be. When the conductor is a coil, the current induced in the coil by the electric field can be increased in proportion to the number of turns of the coil.

[0023] An overview of the exemplary operation and application of a magnetic system in which aspects of various embodiments can be implemented can be provided. The magnitude of the electric field induced on a conductor can be proportional to the rate of change of the magnetic flux density cutting across the conductor. When an electric field is induced in a conductor, the electric field can generate a corresponding current flow in the conductor. The current flow can be in the same direction as the electric field vector at a given point. The peak electric field can occur when the rate of change of the magnetic flux density is at a maximum and can decrease at other times. During a magnetic pulse, the current can flow in a direction to try to sustain the magnetic field (e.g., Lenz's law).

[0024] Certain parts of the biological structure (e.g., nerves, tissues, muscles, brain) can act as conductors and carry electric current when a pulsed magnetic field is applied. The pulsed magnetic field can be applied transcutaneously to these parts of the biological structure. For example, in the context of TMS, a temporally varying magnetic field is applied across the skull and can generate an electric field in the brain tissue, which can create an electric current. If the induced electric current is of sufficient density and / or duration, the neuronal action potential can be reduced to the extent that the membrane sodium channels open and an action potential response is generated. The shock of the current can be propagated along the axonal membrane that transmits information to other neurons via modulation of neurotransmitters. Such magnetic stimulation can acutely affect glucose metabolism and local blood flow in the cortical tissue. In the case of major depressive disorder, abnormal regulation of neurotransmitters and abnormal glucose metabolism in the prefrontal cortex and connected limbic brain structures can be the pathophysiology that can occur. Repeated application of magnetic stimulation to the prefrontal cortex can create chronic changes in neurotransmitter concentration, metabolism, and / or neural changes in the stimulation threshold, such that, for example, depression can be alleviated.

[0025] Non-cortical neurons (e.g., cranial nerves, peripheral nerves, sensory nerves) can be stimulated by an induced electric field. For example, peripheral nerves can be intentionally stimulated to diagnose neuropathy by observing the response time and conduction velocity, for example, in response to a pulsed magnetic field-induced stimulation. Unpleasantness and / or pain may result if the induced electric field applied to the peripheral nerves and / or cranial nerves is very intense and / or focused on a small area of the nerve. For example, this unpleasantness can be reduced by intentionally overstimulating the sensory nerves in the affected nerve bundle so that they can no longer respond to external pain stimuli, or by reducing the intensity and / or focus of the induced electric field that causes the pain sensation.

[0026] Transcranial magnetic stimulation may not be limited to the treatment of depression. Transcranial magnetic stimulation can be used, for example, to treat patients (such as humans) suffering from epilepsy, schizophrenia, Parkinson's disease, Tourette syndrome, amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS), Alzheimer's disease, attention deficit hyperactivity disorder, obesity, bipolar disorder / mania, anxiety disorders (e.g., panic disorder with and without agoraphobia, social anxiety / phobia also known as social anxiety disorder, acute stress disorder, and / or generalized anxiety disorder), post-traumatic stress disorder (one of the anxiety disorders in the DSM), obsessive-compulsive disorder (e.g., one of the anxiety disorders in the DSM), pain (e.g., migraine and trigeminal neuralgia, as well as chronic pain disorders (neuropathic pain, including pain caused by diabetic neuropathy, postherpetic neuralgia), and idiopathic pain disorders, such as fibromyalgia, local fascial pain syndrome, etc.), post-stroke rehabilitation (neuroplasticity induction), tinnitus, stimulation of implanted neurons to promote integration, substance-related disorders (e.g., dependence, abuse, and withdrawal diagnoses related to alcohol, cocaine, amphetamines, caffeine, nicotine, and marijuana, etc.), spinal cord injury and regeneration / rehabilitation, stroke, head injury, reversal of sleep deprivation, primary sleep disorders (primary insomnia, primary hypersomnia, circadian rhythm sleep disorders), improvement of cognitive function, dementia, premenstrual dysphoric disorder (PMS), drug delivery systems (changing cell membrane permeability to drugs), induction of protein synthesis (induction of transcription and translation), stuttering, aphasia, dysphagia, essential tremor, autism spectrum disorder, and / or eating disorders (e.g., bulimia nervosa, anorexia nervosa, and polyphagia, etc.).

[0027] The device can utilize the above principles to induce electric fields for use in various applications. For example, magnetic devices can be used for electrical stimulation of biological structures. The discussion herein focuses on magnetic devices used in connection with magnetic stimulation of anatomical tissues, but magnetic devices can be utilized in any field of activity. Further, since the devices provided herein are described with reference to magnetic stimulation such as transcranial magnetic stimulation (TMS), the devices can be used in connection with any therapeutic or diagnostic procedure.

[0028] A ferromagnetic core can be used in connection with a magnetic device to create a magnetic field. For example, the ferromagnetic core can include a magnetic material in an arcuate shape (e.g., approximately hemispherical). The ferromagnetic core can include a highly saturable magnetic material having a magnetic saturation of at least 0.5 Tesla. The ferromagnetic core can be shaped to optimize the magnetic field distribution within the treatment area. Such a magnetic field can be for the purpose of performing transcranial magnetic stimulation, for example, such as transcranial magnetic stimulation (TMS), repetitive TMS (rTMS), magnetic seizure therapy (MST), deep TMS (dTMS), controlled and / or varied pulse shape TMS (cTMS), reduction of peripheral nerve discomfort, etc. The examples described herein may be discussed in connection with TMS and rTMS, but the examples described herein can be utilized in connection with any type of magnetic stimulation, such as, for example, transcutaneous magnetic stimulation. Moreover, the embodiments presented herein are not limited to the use of ferromagnetic core magnetic stimulation systems since other core materials, such as, for example, an air core, can be used.

[0029] FIG. 1 is a diagram of an example of a treatment or diagnostic system 100. The treatment or diagnostic system 100 may include a processor (not shown), a power supply (not shown), a memory (not shown), a transceiver (not shown), a treatment coil 102, an articulated arm 104, a display device 106, and / or a human subject positioning device 122. The treatment system 100 may be stationary or movable. For example, the treatment system 100 may be integrated into a movable cart, as shown in FIG. 1, for example. In one or more examples, the treatment system 100 can be a TMS treatment system (e.g., NeuroStar®) and / or any other medical treatment and / or diagnostic procedure system.

[0030] The treatment coil 102 can be used to administer a medical treatment and / or diagnostic procedure to a human subject 120, such as TMS, for example. An exemplary treatment coil 102 can include one or more treatment coils and one or more ferromagnetic components, and the one or more ferromagnetic components are configured to be disposed proximate to corresponding ones of the one or more treatment coils. The one or more treatment coils and ferromagnetic components of each TMS device can cooperatively generate a magnetic field having one or more characteristics different from that of the magnetic field generated by the one or more treatment coils alone. Although the treatment coil 102 is shown and described primarily with respect to TMS, the treatment system 100 can include any device for administering a medical treatment and / or diagnostic procedure to a human subject. In some examples, the treatment system 100 can be used for diagnostic procedures (e.g., only for diagnostic procedures).

[0031] The processor of the treatment system 100 may be a general-purpose processor, a dedicated processor, a conventional processor, a digital signal processor (DSP), multiple microprocessors, one or more microprocessors associated with a DSP core, a controller, a microcontroller, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) circuit, any other type of integrated circuit (IC), and a state machine, etc. The processor may perform signal coding, data processing, power control, input / output processing, and / or any other functionality that enables the treatment system 100 to operate. The processor may be integrated with one or more other components of the treatment system 100 within an electronic package or chip.

[0032] The processor of the treatment system 100 may be connected to the treatment coil 102, the articulated arm 104, the display device 106 (e.g., a liquid crystal display (LCD) display unit or an organic light-emitting diode (OLED) display unit), and / or the human subject positioning device 122, and may receive user input data from them and / or send output user input data to them. The processor may access information from any type of suitable memory (e.g., non-removable memory and / or removable memory, etc.), and may store data in any type of suitable memory. The non-removable memory may include a random access memory (RAM), a read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory may include a subscriber identity module (SIM) card, a memory stick, and a secure digital (SD) memory card, etc. The processor may access information from the memory and may store data in the memory, and the memory is not physically located within the treatment system 100, but is located, for example, on a server (not shown).

[0033] The processor can receive power from the power supply unit and can be configured to distribute and / or control power to other components within the treatment system 100. The power supply unit can be any suitable device for powering the treatment system 100.

[0034] The human subject 120 can be positioned within the human subject positioning device 122. The human subject positioning device 122 can be, for example, a chair, recliner, bed, and / or stool. When performing treatment, the treatment coil 102 can be positioned such that the head of the human subject is positioned under the treatment coil 102. The treatment coil 102 can be adjusted by, for example, an articulated arm 104 and / or the like.

[0035] The treatment system 100 can include one or more computer software applications that run on the processor. The computer software application can provide a system graphical user interface (GUI) (e.g., a TMS system GUI) on the display device 106. The computer software application can incorporate workflow management, guide the technician through clinical and / or diagnostic procedures, and / or monitor and / or control one or more subsystems of the treatment system 100. For example, the computer software application can control internal system functions, monitor the system situation to ensure safe operation, and / or provide graphical means to the user for managing the preparation for and / or performing clinical and / or diagnostic procedures.

[0036] The interaction with a computer software application can be provided via a user interface. In one or more embodiments, the user interface can be a display device 106, and the display device 106 can be a touch screen display. The display device 106 can include alphanumeric keys and / or touch-activated images of buttons for user interaction with the treatment system 100. The display device 106 can provide a graphical representation of system activity, messages, and / or alarms. Interactive buttons, fields, and / or images can be displayed via the display device 106, enabling a technician to instruct and / or interact with system functions, which can include, for example, entering data, starting and stopping procedures, performing diagnostics, adjusting the positioning and / or configuration of the treatment coil 102, and / or adjusting the position of one or more sensors.

[0037] The treatment system 100 can be used for any medical and / or diagnostic procedure. For example, the treatment system can be used for TMS, transcranial direct current stimulation (tDCS), electroencephalography (EEG), deep brain stimulation (DBS), and / or diagnostic procedures. For example, the treatment system 100 can be used for any medical and / or diagnostic procedure that includes the placement of electrodes, sensors, and / or probes on a human subject (such as on the surface of the head of a human subject). Although described with reference to a head model, the treatment system 100 can be configured to generate models of any part of a human subject 120, including but not limited to, the arm, neck, chest, and / or leg.

[0038] FIG. 2 is a block diagram illustrating an example of a magnetic stimulation system 200. The magnetic stimulation system 200 can be an example of the treatment system 100. The magnetic stimulation system 200 can include a sensor 210, a controller 220, a user interface 230, a power supply 240, and a magnetic stimulation component 250. The magnetic stimulation component 250 can be an example of the treatment coil 102 of the treatment system 100 in FIG. 1.

[0039] The magnetic stimulation component 250 can be configured to generate a pulsed magnetic field 260 to perform magnetic stimulation therapy on a treatment area of a patient. The magnetic stimulation therapy can be, for example, transcranial magnetic stimulation (TMS). TMS can refer to TMS, repetitive transcranial magnetic stimulation (rTMS), deep TMS (dTMS), or cTMS, etc. The magnetic stimulation component 250 can be a treatment coil. The magnetic stimulation component 250 can be a single treatment coil, a plurality of treatment coils, and / or an array of treatment coils. The treatment area can be, for example, the prefrontal cortex. The magnetic stimulation component 250 may or may not include a core (such as a magnetic core (such as a ferromagnetic core), etc.). The pulsed magnetic field 260 can be one or more pulse bursts. The pulse burst of the pulsed magnetic field 260 (for example, each pulse burst) can be one or more pulses.

[0040] Sensor 210 can be configured to generate a signal associated with the pulsed magnetic field 260. Sensor 210 can be disposed between the magnetic stimulation component 250 and the treatment area of the patient. Sensor 210 can be configured to generate a signal associated with the pulsed magnetic field 260 of the magnetic stimulation component 250 (e.g., a signal induced by the pulsed magnetic field 260). For example, sensor 210 can convert a physical property (e.g., the intensity of the pulsed magnetic field 260) into a corresponding electrical signal (e.g., a current signal or a voltage signal). Thus, sensor 210 can detect and / or measure the physical parameters of the pulsed magnetic field and use the detected / measured physical parameters to generate a signal associated with the pulsed magnetic field. The generated signal can be a voltage signal and / or a current signal proportional to the change in the pulsed magnetic field 260. For example, a current can be generated in sensor 210, which can be proportional to the pulsed magnetic field 260. Sensor 210 can generate a voltage proportional to the magnetic flux density (dB / dt) of the pulsed magnetic field 260.

[0041] Sensor 210 can include one or more of a conductive coil, a loop (e.g., having a plurality of turns based on the pulsed magnetic field), a Hall sensor, a magnetoresistive material, a Faraday effect sensor, a Kerr effect sensor, a fluxgate sensor, an inductance change element, a nerve tissue response measurement device, and / or an electric field sensor (e.g., in a conductive field). Sensor 210 can be configured to generate two or more signals, e.g., two or more signals associated with the pulsed magnetic field 260 generated by the magnetic stimulation component 250.

[0042] The controller 220 can be of any type of hardware, software, or a combination thereof. The controller 220 can be configured to control one or more of the components of the magnetic stimulation system 200 (such as, for example, the sensor 210, the user interface 230, the power supply 240, and / or the magnetic stimulation component 250, etc.) in order to perform magnetic stimulation therapy. For example, the controller 220 can include a general-purpose processor, a dedicated processor, a conventional processor, a digital signal processor (DSP), multiple microprocessors, one or more microprocessors associated with a DSP core, a microcontroller, any other type of integrated circuit (IC), and / or a state machine, etc.

[0043] The controller 220 can receive inputs from the user interface 230 and / or the sensor 210 and can be configured to perform magnetic stimulation therapy accordingly. For example, the controller 220 can perform signal coding, data processing, power control, input / output processing, and / or any other functionality that enables the controller 220 to operate the magnetic stimulation component for magnetic stimulation. The controller 220 can include a drive circuit, and the drive circuit can generate a drive signal for driving (such as, for example, powering, such as applying a pulse, etc.) the magnetic simulation component 250. In some examples, the drive circuit can be separated from the controller 220 and can be electrically connected to the magnetic stimulation component 250.

[0044] Furthermore, the controller 220 may be configured to modify the drive signal provided to the magnetic stimulation component 250 based on inputs received from the user interface 230 and / or the sensor 210. The controller 220 may be configured to estimate (e.g., measure) a characteristic associated with the signal generated by the sensor 210 (e.g., associated with one or more peaks of the signal). The controller 220 may estimate a subset of the signal pulses or may estimate the signal continuously. By estimating the characteristics of the signal, the controller 220 may estimate a model of what occurs in the patient's brain in response to the pulsed magnetic field.

[0045] Furthermore, the controller 220 may determine whether a failure has occurred based on one or more characteristics of the signal generated by the sensor 210. If it is determined that a failure has occurred, the controller 220 may enter a failure mode. In the failure mode, the controller 220 may pause the magnetic stimulation procedure, stop the magnetic stimulation component 250, warn the user of the magnetic stimulation system 200, and / or change the current applied to the magnetic stimulation component 250. For example, when the controller 220 enters the failure mode, the controller 220 may adjust the frequency at which it estimates the characteristics of the generated signal. For example, the controller 220 may check for failures more frequently after a first failure is detected. Additionally, the magnetic stimulation system 200 may include an indicator that may indicate to the user of the magnetic stimulation system 200 that a failure has occurred. For example, the indicator may be a light, a speaker, and / or an icon displayed on the user interface 230.

[0046] The user interface 230 can be any type of interface that allows a user of the magnetic stimulation system 200 to initiate, adjust, and / or terminate a magnetic stimulation procedure. For example, the user interface can include a personal computer (PC), keyboard, mouse, touch screen, and / or wireless device, etc., which enables an interface between the user and the magnetic stimulation system 200.

[0047] The power supply 240 can be any type of power source that provides sufficient energy for the magnetic stimulation component 250 to generate a pulsed magnetic field 260 for its intended purpose (e.g., for TMS, rTMS, MST, or any other type of application). For example, the power supply 240 can be a conventional 120VAC or 240VAC main power supply.

[0048] Figures 3 to 11H are examples of treatment coils that can be used in the treatment system 100 and / or the magnetic stimulation system 200. The treatment coils described with reference to Figures 3 to 11H can be used as treatment coils in a treatment or diagnostic system (e.g., the treatment coil 102 in the treatment or diagnostic system 100) and / or as part of the magnetic stimulation component of a magnetic stimulation system (e.g., the magnetic stimulation component 250 of the magnetic stimulation system 200). Further, although described as being driven by a single drive circuit, the treatment coils described with reference to Figures 3 to 11H can be driven by multiple drive circuits, for example, by drive circuits for each conductive element or for a subset of the conductive elements of the treatment coil. Also, the conductive elements described with reference to Figures 3 to 11H can include any suitable material such as Litz wire.

[0049] The treatment coils described with reference to FIGS. 3 to 11H may include one or more ferromagnetic components. In some examples, the ferromagnetic component may be referred to as a magnetic core. The ferromagnetic component may be composed of any combination of a powdered magnetic material, a laminated magnetic material, an amorphous magnetic material, one or more of alloys of iron, nickel, or cobalt, and / or a rare earth element or alloy, such as gadolinium, neodymium, or holmium. For example, the ferromagnetic components described herein may be composed of any suitable material, and in some examples, the ferromagnetic components may be made of a plurality of different materials, where the materials define different saturation levels. Some examples of the treatment coils are described with the ferromagnetic components included, but any of the treatment coils described herein may include a subset of the illustrated ferromagnetic components, and / or the ferromagnetic components may be omitted.

[0050] Also, it should be recognized that a direct current (DC) magnetic field and / or a permanent magnet may be used within any of the treatment coils described herein, for example, to modify the magnetic susceptibility of the ferromagnetic component, reshape the magnetic field, and / or change the separation of the activation zones generated by the treatment coil.

[0051] Finally, it should be recognized that any of the treatment coils described herein (e.g., treatment coils 300, 400, 500, 600, 700, 800, 900, 1000, and / or 1100) may be configured to generate a magnetic field that induces one or more activation zones (e.g., two activation zones) in a subject (e.g., at one or more target locations). Thus, while the treatment coils are primarily described as generating a magnetic field that induces two activation zones, any of the treatment coils described herein may be configured to generate a magnetic field that induces more or fewer than two activation zones.

[0052] Figure 3 shows an exemplary treatment coil 300 configured to generate a varying magnetic field within a target biological structure of a subject, such as a human subject (not shown). The target biological structure of the subject can be, for example, the brain tissue of the subject. The treatment coil 300 includes a first conductive element 310, a second conductive element 320, and a third conductive element 330. The treatment coil 300 can be disposed proximate to the head of the subject, for example, for preparation of TMS treatment or during TMS treatment, as shown in FIG. 1. Although not shown, the treatment coil 300 can further include ferromagnetic components. The combination of the conductive elements 310, 320, 330 and the ferromagnetic components can collectively be referred to as, for example, an electromagnet. It should be recognized that the treatment coil 300 can include more or fewer conductive elements than those shown. The conductive elements can be referred to as conductive windings.

[0053] The conductive elements 310, 320, 330 can be made of any material exhibiting suitable electrical conductivity, such as copper. The first and second conductive elements 310, 320 can be fabricated from pieces of different materials or from a monolithic piece of material. For example, a material of a predetermined length (e.g., wire) can be continuously wound to define each of the first and second conductive elements 310, 320. The conductive elements 310, 320, 330 are fabricated and supported separately from one another and can be attached to one another using, for example, one or more attachment members (not shown). A plurality of separately fabricated conductive elements (e.g., the first and second conductive elements 310, 320) can be installed in electrical communication with one another using, for example, one or more conductive attachment members that interconnect the respective conductive elements.

[0054] The conductive elements 310, 320, 330 can define any suitable shape, for example, a substantially circular shape as shown. For example, the conductive elements 310, 320, 330 can have the same or different shapes as those shown, and can have the same or different shapes from each other (e.g., circular, elliptical, oval, rectangular, etc.). Further, one or more of the conductive elements 310, 320, 330 can be configured to define a geometric shape that matches a region of the subject's head. For example, one or more of the conductive elements (a portion of the whole of them) can define a concave band-shaped coil geometry that matches a portion of the subject's head (or, for example, another target biological structure).

[0055] The treatment coil 300 can define an asymmetric figure-eight coil (e.g., a figure-eight coil in which one loop of the "8" is sized or shaped differently from the other loop of the "8", and / or a figure-eight coil in which one or more additional conductive elements are added to a traditional figure-eight coil to disrupt the symmetry of the "8", etc.). For example, the treatment coil 300 can include two conductive elements 310, 320 that define one loop of the "8" and one conductive element 330 that defines the other loop of the "8". Thus, the treatment coil 300 can define an asymmetric figure-eight coil. Further, the conductive element 310 can define a perimeter that is larger than the perimeter defined by the conductive element 320 and / or the perimeter defined by the conductive element 330. Further, in some examples, the perimeter defined by the conductive element 330 can be equal to the perimeter defined by the conductive element 320. However, it should be recognized that in some examples, the perimeter defined by the conductive element 330 can be larger or smaller than the perimeter defined by the conductive element 320.

[0056] The conductive elements 310, 320, and 330 may be positioned such that the second conductive element 320 is disposed within the opening defined by the first conductive element 310. Further, the central axis 322 of the second conductive element 320 may be offset from the central axis 312 of the first conductive element 310. Thus, the first and second conductive elements 310, 320 are not concentric. The distance between the second conductive element 320 and the first conductive element 310 may be any suitable distance (e.g., such that the first and second conductive elements are not concentric). In other examples, the first and second conductive elements 310, 320 may be concentric. The third conductive element 330 may be positioned outside the peripheral portion of the first conductive element 310, but the first and third conductive elements 310, 330 may be positioned close to each other. A small gap (not shown) may be positioned between the adjacent side portions of the first and third conductive elements 310, 330, while in some examples, the first and third conductive elements 310, 330 may be in contact with each other. Further, in some examples, the conductive element 310 may be disposed closer to the conductive element 330 than to the conductive element 320.

[0057] During the treatment of the diagnostic procedure, the treatment coil 300 may be disposed such that the area 340 where the first conductive element 310 is close to the third conductive element 330 is disposed above the target stimulation zone of the subject. Thereafter, the treatment coil 300 may be driven by a drive circuit of the treatment system and / or the magnetic stimulation system. For example, when driven, the treatment coil 300 may be configured such that current circulates in a first direction (e.g., clockwise as viewed from the top perspective as shown) through the first and second conductive elements, while current circulates in an opposite second direction (e.g., counterclockwise as viewed from the top perspective as shown) through the third conductive element.

[0058] As a result, the treatment coil 300 can be configured to generate a magnetic field that causes an increased stimulation in an area 340 where the first conductive element 310 is close to the third conductive element 330 (e.g., via a more powerful pulsed magnetic field), as compared to an area substantially opposite to the third conductive element 330 (e.g., area 350, etc.). Since this is the case, the coil configuration of the treatment coil 300 can provide an increased stimulation around the treatment area (e.g., close to area 340, e.g., below area 340), and can provide a reduced stimulation (e.g., a reduced return current) in an area outside the target stimulation zone (e.g., area 350).

[0059] Furthermore, the conductive element 310 can be disposed closer to the conductive element 330 than to the conductive element 320. Including the conductive element 310 along with the relative locations of the conductive element 310 with respect to the conductive elements 320 and 330 (e.g., the conductive element 310 is disposed closer to the conductive element 330 than to the conductive element 320), as compared to a situation where the conductive element 310 is not included (e.g., compared to a symmetric figure-eight coil), and / or as compared to a situation where the conductive element 310 is disposed closer to the conductive element 320 than to the conductive element 330, can shift the magnetic field generated by the treatment coil 300 in the direction defined by the arrow 360 closer to the area 350. For example, including the conductive element 310 disposed closer to the conductive element 330 than to the conductive element 320 can directly shift the magnetic field from the area between the conductive element 320 and the conductive element 330 to an area 340 shifted closer to the area 350, along the direction defined by the arrow 360, without increasing the current level induced close to the area 350.

[0060] Without increasing the current level induced in the vicinity of area 350, shifting the magnetic field directly from the area between conductive element 320 and conductive element 330 closer to area 350 (e.g., similar to the case of a symmetric figure-eight coil) can be beneficial for certain therapeutic or diagnostic procedures. For example, when the treatment coil 300 is in a position close to the patient, the treatment area may be close to area 340, and there may be an area where it is not desirable to stimulate directly opposite area 350. For example, during some procedures, while positioning area 350 close to the patient's paranasal sinuses or nasal septum (where induction of stimulation may not be desirable), it may be desirable to position area 340 close to the dorsomedial cortex or prefrontal cortex for stimulation of the dorsomedial cortex or prefrontal cortex.

[0061] The treatment coil 300 can be configured in other arrangements to shift the magnetic field in the direction defined by arrow 360 from the area directly between conductive element 320 and conductive element 330 to area 340, which is closer to area 350. For example, if conductive element 330 is made with a smaller diameter, if conductive element 310 and / or 320 are made with a larger diameter, and / or if conductive element 320 is moved further away from conductive element 330, the generated magnetic field can be shifted closer to area 350.

[0062] In the illustrated example, the first, second, and third conductive elements 310, 320, 330 each define a single loop (e.g., a single amp-turn). In some examples, the treatment coil 300 may include additional conductive elements and / or conductive elements that define multiple loops (e.g., amp-turns). For example, the treatment coil 300 may include more conductive elements (or, e.g., conductive elements that define more loops) on one side than on the other side (e.g., the side having the first and second conductive elements 310, 320, or the side having the third conductive element 330). For example, a fourth conductive element may be included within the aperture of the second conductive element 320, and in a further example, a fifth conductive element may be included within the aperture of the third conductive element 330. The fourth and fifth conductive elements need not be concentric with the second and third conductive elements, respectively. Thus, the treatment coil 300 may include any number of additional conductive elements (or, e.g., conductive elements that define more loops) as long as there are more conductive elements on one side than on the other side. Further, when driven, current may circulate through the fourth conductive element in a first direction (e.g., the same direction as the first and second conductive elements 310, 320), while current may circulate through the fifth conductive element in an opposite second direction (e.g., the same direction as the third conductive element 330).

[0063] Further, as described above, the stimulation coil 300 may include a ferromagnetic component (not shown). The ferromagnetic component may be configured to change one or more characteristics of the magnetic field generated by the treatment coil 300. The ferromagnetic component may be made from any material that exhibits suitable ferromagnetic properties, such as powdered ferromagnetic iron particles. Further, the ferromagnetic component may define any suitable shape, such as a circular shape, a semi-elliptical band shape, etc.

[0064] The ferromagnetic component can be positioned close to the treatment coil 300. For example, the ferromagnetic component can be positioned within the opening of the first conductive element 310 (e.g., in addition to, or instead of, the second conductive element 320). The center of the ferromagnetic component can be offset from the central axis 312 of the first conductive element 310 (and, if included, the second conductive element 320, for example). For example, if the ferromagnetic component has a circular cross-section, the ferromagnetic component need not be concentric with the first conductive element 310. By offsetting the ferromagnetic component from the central axis 312 of the first conductive element 310, the treatment coil 300 can be configured to generate a magnetic field that is offset from the area 340 where the first conductive element 310 is close to the third conductive element 330. Moreover, in some examples, the ferromagnetic component can be configured to at least partially receive or enclose a portion or all of the treatment coil 300. For example, the ferromagnetic component can define a recess that is configured to receive at least a portion of the treatment coil 300, and when the treatment coil 300 is disposed within the recess, the ferromagnetic component is configured to at least partially surround respective portions of the conductive elements 310, 320, 330.

[0065] In some examples, the treatment coil 300 can include a bend and is configured to define an angle (e.g., a 90-degree angle, etc.) such that the return current curls up from the head. For example, any combination of the conductive elements 310, 320, 330 can define a bend that defines an angle (e.g., a 90-degree angle, etc.) that allows the return current to curl up from the head. Further, in some examples, the treatment coil 300 can include one or more additional conductive elements that define an angle (e.g., a 90-degree angle, etc.) that allows the return current to curl up from the head.

[0066] Figures 4A and 4B show an exemplary treatment coil 400, which is configured to generate a changing magnetic field within a target biological structure of a subject, such as a human subject (not shown). The target biological structure of the subject can be, for example, the brain tissue of the subject. The treatment coil 400 includes a first conductive element 410, a second conductive element 420, and a ferromagnetic component 430. The treatment coil 400 can be disposed proximate to the head of the subject, for example, for preparation of TMS treatment or during TMS treatment, as shown in FIG. 1. The combination of the conductive elements 410, 420 and the ferromagnetic component 430 can collectively be referred to as, for example, an electromagnet. It should be recognized that the treatment coil 400 can include more or fewer conductive elements than those shown. The conductive elements can be referred to as conductive windings. Further, in some examples, it should be recognized that the treatment coil 400 may not include the ferromagnetic component 430.

[0067] The first conductive element 410 can have a substantially circular shape, for example, as shown. The first conductive element 410 can define an inner surface 412, an outer surface 414, an upper surface 416, and a bottom surface 418. The second conductive winding 420 can define a non-circular or non-oval shape. For example, the second conductive element 420 can be shaped, for example, as shown, into a crescent shape (e.g., shaped like a bow, kidney, or sickle).

[0068] The second conductive element 420 may define an inner surface 422, an outer surface 424, an upper surface 426, and a bottom surface 428. The outer surface 424 of the second conductive element 420 may include a convex portion 425 and a concave portion 427. The first conductive winding 410 may be disposed proximate to the concave portion 427 of the outer surface 424 of the second conductive element 420. For example, the outer surface 412 of the first conductive winding 410 may be disposed proximate to the concave portion 427 of the outer surface 424 of the second conductive element 420. For example, the concave portion 427 of the second conductive element 420 may define a concave surface, and at least a portion of the first conductive winding 410 may be disposed within the concave surface of the second conductive element 420. At least a portion of the first conductive winding 410 may be disposed within the concave surface of the second conductive element 420, but in some examples (such as those shown), the second conductive element 420 may not encapsulate the first conductive winding 410.

[0069] The first and second conductive elements 410, 420 may be made of any material exhibiting suitable electrical conductivity, such as copper. The first and second conductive elements 410, 420 may define the same number of turns (e.g., ampere-turns), such as a single turn as shown. However, it should be recognized that in some examples, the first conductive element 410 may define a first number of turns, while the second conductive element 420 may define a different second number of turns. Further, in some examples, the treatment coil 400 may include additional conductive elements and / or conductive elements defining multiple loops (e.g., ampere-turns). For example, the first conductive element 410 may include one or more additional and overlapping conductive elements (e.g., the first conductive element 410 may define multiple loops), and / or the second conductive element 420 may include one or more additional and overlapping conductive elements (e.g., the second conductive element 420 may define multiple loops).

[0070] The first conductive element 410 and / or the second conductive element 420 can be formed from a single monolithic piece of conductive material, or one or more of the first and second conductive elements 410, 420 can be formed by a plurality of strands of wire. In some examples, the conductive elements 410, 420 are fabricated and supported separately from each other and can be attached to each other using, for example, one or more attachment members (not shown). Further, the treatment coil 400 can include a housing (not shown) that houses the first and second conductive windings 410, 420 and the ferromagnetic component 430.

[0071] The ferromagnetic component 430 can be made from any material that exhibits suitable ferromagnetic properties, such as powdered ferromagnetic iron particles. The ferromagnetic component 430 can include a body portion 432, a first protruding portion 434, and a second protruding portion 436. The body portion 432 can have an upper surface 438, and the upper surface 438 can be substantially parallel to the upper surface 416 of the first conductive winding 410 and the upper surface 426 of the second conductive winding 420. The first protruding portion 434 can extend from the bottom surface of the body portion 432. The first protruding portion 434 can be disposed within the opening of the first conductive element 410. The first protruding portion 434 can have a cross-sectional shape that is substantially similar to the shape of the opening of the first conductive element 410 (e.g., a substantially circular cross-sectional shape). Further, in the example shown, the bottom surface 440 of the first protruding portion 434 can be substantially planar with the bottom surface 418 of the first conductive element 410. However, in some examples, it should be recognized that the first protruding portion 434 can be configured to extend through the first conductive element 410 such that the bottom surface 440 of the first protruding portion 434 extends beyond the plane of the bottom surface 418 of the first conductive element 410.

[0072] The second protruding portion 436 may extend from the bottom surface of the body portion 432. The second protruding portion 436 may be disposed within the opening of the second conductive element 420. The second protruding portion 436 may have a cross-sectional shape that is substantially the same as the shape of the second conductive element 420 (e.g., a cross-sectional shape shaped like a crescent). Further, in the illustrated example, the bottom surface 442 of the second protruding portion 436 extends beyond the plane of the bottom surface 428 of the second conductive element 420. However, it should be recognized that in some examples, the second protruding portion 436 may be configured such that the bottom surface 442 of the second protruding portion 436 can be substantially planar with the bottom surface 428 of the second conductive element 420.

[0073] During the treatment of the diagnostic procedure, the treatment coil 400 may be arranged such that the area where the first conductive element 410 is close to the second conductive element 420 can be placed above the target stimulation zone of the subject. For example, the area where the outer surface 412 of the first conductive winding 410 is disposed close to the concave portion 427 of the outer surface 424 of the second conductive winding 420 can be placed above the target stimulation zone of the subject. Thereafter, the treatment coil 400 may be driven by the drive circuit of the treatment system and / or the magnetic stimulation system. For example, when driven, a current circulates through the first conductive element 410 in a first direction (e.g., clockwise when viewed from the bottom perspective as shown in FIG. 4A), while a current circulates through the second conductive element 420 in the opposite second direction (e.g., counterclockwise when viewed from the bottom perspective as shown in FIG. 4A), so that the treatment coil 400 can be configured.

[0074] As a result, the treatment coil 400 can be configured to generate a magnetic field that induces an activation zone (e.g., a stimulation zone) at a target location having a crescent shape (e.g., similar to the shape of the second conductive element 420), substantially below the area where the outer surface 412 of the first conductive winding 410 is disposed close to the concave portion 427 of the outer surface 424 of the second conductive winding 420. For example, the treatment coil 400 can also be configured to generate a magnetic field that induces an activation zone at a target location having a crescent shape, without inducing a stimulation zone in the area of the first conductive element 410 that is disposed away from the concave portion 427 of the outer surface 424 of the second conductive winding 420. Thus, the treatment coil 400 can be used to generate a stimulation zone at a target location that encloses an area where stimulation is not desired (e.g., inside the concave surface of the activation zone).

[0075] When driven, the treatment coil 400 can be configured such that current circulates in a first direction through the first conductive element 410 while current circulates in an opposite second direction through the second conductive element 420, so that the treatment coil 400 can generate a localized activation zone (e.g., also shaped like a crescent). That is, since current circulates in opposite directions through the first conductive element 410 and the second conductive element 420, and since the first and second conductive elements 410, 420 are not concentric with each other, the return currents flow in opposite directions (e.g., the currents flowing through the first and second conductive elements 410, 420 outside the activation zone flow in opposite directions as they leave the activation zone).

[0076] Furthermore, it should be recognized that the concave surface of the second conductive element 420 (e.g., the degree or angle of the concave portion 427 of the outer surface 424 of the second conductive winding 420) can be adjusted to adjust the stimulation zone resulting from what is caused by the treatment coil 400. For example, in some examples, the second conductive element 420 can be adjustable to modify the angle of the concave surface of the outer surface 424. For example, the second conductive element 420 can include a hinge (e.g., at its midpoint), can be composed of a plurality of interchangeable sections having different degrees or angles of the concave surface, and can be made of a flexible material, either wholly or in part. Furthermore, in some examples, the shape of the first conductive element 410 can be adjusted to match the degree or angle of the concave portion 427 of the outer surface 424 of the second conductive element 420. Finally, in some examples, one or both of the first and second conductive elements 410, 420 can be replaced with different elements having different but corresponding curvatures (e.g., as opposed to making the second conductive element 420 adjustable).

[0077] Furthermore, the angle of curvature of the outer surface 424 of the convex portion 425 of the second conductive element 420 is adjusted so that, for example, it can be ensured that the generated stimulation zone does not enclose an area where stimulation is not desired. For example, the treatment coil 400 can be arranged such that the convex portion 425 curves upward above the patient's eye (where it may be desirable to avoid stimulation) (e.g., from the perspective view provided by FIG. 4B).

[0078] The treatment coil 400 can be configured such that when the first and second conductive windings 410, 420 are driven, the resulting activation zone encompasses two independent areas within the subject's brain (e.g., a crescent shape encompasses two areas of the brain). The areas within the subject's brain can be correlated with different functional regions of the brain. For example, the treatment coil 400 can be used to stimulate two different areas within the subject's brain, such as a first area positioned below and proximate to one side of the second conductive element 420, and a second area positioned below and proximate to the other side of the second conductive element 420 (e.g., at either end of the crescent shape). The currents in the two areas of the brain can move in the same direction or in different directions (e.g., clockwise and / or counterclockwise).

[0079] The activation zone induced by the magnetic field generated by the treatment coil 400 can be a stimulation zone or a sub-stimulation zone. The stimulation zone can be at a level where the induced current caused by the pulsed magnetic field generated by the treatment coil 400 exceeds the depolarization threshold of the neurons in the brain, while the sub-stimulation zone can be at a level where the induced current is below the depolarization threshold of the neurons in the brain. Further, although two activation zones and two treatment areas have been described, the treatment coil 400 can be used to generate a magnetic field that induces more or fewer activation zones for more or fewer treatment areas of the patient (e.g., depending on a particular treatment or diagnostic procedure).

[0080] The treatment coil 400 can be configured such that the conductive elements 410, 420 and the ferromagnetic component 430 support each other. For example, the treatment coil 400 can be configured such that the ferromagnetic component 430 supports the conductive elements 410, 420. One or both of the conductive elements 410, 420 and the ferromagnetic component 430 can include one or more complementary attachment members (not shown), and the one or more complementary attachment members are configured to be able to attach (e.g., releasably attach) the conductive elements 410, 420 to the ferromagnetic component 430. The one or more attachment members can be configured such that the conductive elements 410, 420 and the ferromagnetic component 430 are fixedly supported with respect to each other. The one or more attachment members can be configured such that the conductive elements 410, 420 and the ferromagnetic component 430 are movable (e.g., repositionable) with respect to each other.

[0081] When the conductive elements 410, 420 are supported (e.g., attached) by the ferromagnetic component 430, the conductive elements 410, 420 can be electrically isolated from the ferromagnetic component 430, for example, using a dielectric. The dielectric can be air, and when the conductive elements 410, 420 are attached to the ferromagnetic component 430, the conductive elements 410, 420 can be spaced apart from the ferromagnetic component 430 (e.g., not in direct contact with the ferromagnetic component 430). The conductive elements 410, 420 can be attached to the ferromagnetic component 430 using one or more attachment members made of any suitable electrically isolating (e.g., dielectric) material.

[0082] Furthermore, although not shown, in some examples, the treatment coil 400 may include a conductive element surrounding the ferromagnetic element 430. For example, the conductive element may surround the upper surface 438 of the ferromagnetic element 430. The conductive element may be lifted above the upper surface 438, and the conductive element may define an opening that is lifted above the upper surface 438 of the ferromagnetic component 430. Additionally, in some examples, the conductive element may surround the entirety of the first and second conductive elements 410, 420 as well as the ferromagnetic component 430.

[0083] Although not shown, in some examples, one or both of the conductive elements may define a bend such that the conductive element defines a predetermined angle (e.g., a 90-degree angle, etc.) that allows the return current to curl up from the patient's head. Also, in some examples, the upper surface 438 of the body portion 432 of the ferromagnetic component 430 may be arched or rounded.

[0084] Furthermore, it should be recognized that in some examples, the spacing between the outer surface 414 of the first conductive element 410 and the outer surface 424 of the concave portion 427 of the second conductive element 420 may vary (e.g., it may vary throughout the entire concave surface defined by the concave portion 427). For example, the first conductive element 410 may be offset into the concave surface defined by the concave portion 427 of the second conductive element 420, or the outer surfaces of the first and second conductive elements 420 may be non-complementary to each other (e.g., defining different shapes and / or curvatures).

[0085] Figures 5A and 5B show an exemplary treatment coil 500, which is configured to generate a changing magnetic field within a target biological structure of a subject, such as a human subject (not shown). The target biological structure of the subject can be, for example, the brain tissue of the subject. The treatment coil 500 includes a first conductive element 510, a second conductive element 520, and a ferromagnetic component 530. The treatment coil 500 can be disposed proximate to the head of the subject, for example, as shown in FIG. 1, for preparation of TMS treatment or during TMS treatment. The combination of the conductive elements 510, 520 and the ferromagnetic component 530 can collectively be referred to as, for example, an electromagnet. It should be recognized that the treatment coil 500 can include more or fewer conductive elements than those shown. The conductive elements can be referred to as conductive windings.

[0086] The first and second conductive elements 510, 520 may be semi-elliptical in shape (e.g., have a rounded rectangular shape). Further, in some examples, the first and second conductive elements 510, 520 can be of another shape, for example, circular in shape. In some examples, the first and second conductive elements 510, 520 can together form an eight-shaped coil or a B-shaped coil. The first conductive element 510 can define a bottom surface 512, an upper surface 514, an inner surface 516, and an outer surface 518. Similarly, the second conductive element 520 can define a bottom surface 522, an upper surface 524, an inner surface 526, and an outer surface 528. The first and second conductive elements 510, 520 can be made from any material that exhibits a suitable electrical conductivity, such as, for example, copper.

[0087] The first and second conductive elements 510, 520 may define the same number of turns (e.g., amp-turns), e.g., a single turn as illustrated. However, in some examples, it should be recognized that the first conductive element 510 and / or the second conductive element 520 may define a plurality of turns. For example, in some examples, the first conductive element 510 may define a first number of turns, while the second conductive element 520 may define a different second number of turns. Further, in some examples, the treatment coil 500 may include additional conductive elements and / or conductive elements that define a plurality of loops (e.g., amp-turns). For example, the first conductive element 510 may include one or more additional and overlapping conductive elements (e.g., the first conductive element 510 may define a plurality of loops), and / or the second conductive element 520 may include one or more additional and overlapping conductive elements (e.g., the second conductive element 520 may define a plurality of loops).

[0088] The first conductive element 510 and / or the second conductive element 520 may be formed from a single monolithic piece of conductive material, or one or more of the first and second conductive elements 510, 520 may be formed by a plurality of strands of wire. In some examples, the treatment coil 500 may include a housing (not shown) that houses the first and second conductive windings 510, 520 and the ferromagnetic component 530.

[0089] The ferromagnetic component 530 can be made from any material that exhibits suitable ferromagnetic properties, such as powdered ferromagnetic iron particles. The ferromagnetic component 530 can include a main body portion 538 and a plurality of poles, and the plurality of poles can be, for example, a first pole 532, a second pole 534, and a third pole 536 that extend from the main body portion 538. Although it is illustrated as having three poles, in some examples, the ferromagnetic component 530 can include more or fewer than three poles. The plurality of poles (e.g., the first, second, and third poles 532, 534, 536) can extend outwardly from the main body portion 538 (e.g., from the bottom surface 533 of the main body portion 538). The third pole 536 can be present between the first pole 532 and the second pole 534. For example, the first, second, and third poles 532, 534, 536 can be linearly aligned (as illustrated, for example). However, it should be recognized that in some examples, one or more of the first, second, and / or third poles 532, 534, 536 can be aligned in a non-linear manner.

[0090] The main body portion 538 of the ferromagnetic component 530 can define an upper surface 531 and a bottom surface 533. The main body portion 538 can be curved, for example, as illustrated. For example, the upper surface 531 of the main body portion 538 can define a convex surface, while the bottom surface 533 of the main body portion 538 can define a concave surface. Thus, the upper surface 531 can be non-planar, and the bottom surface 533 can also be non-planar. Additionally, it should be recognized that in some examples, the curvature of the upper surface 531 and / or the bottom surface 533 of the main body portion 538 can define a curvature that is greater or less than that illustrated. Moreover, it should be recognized that in some examples, the upper surface 531 and / or the bottom surface 533 of the main body portion 538 can be planar (e.g., flat).

[0091] The first pole 532 may define a first pole surface 542, the second pole 534 may define a second pole surface 544, and the third pole 536 may define a third pole surface 546. The first pole 532 may be disposed within an opening of the first conductive element 510, and the second pole 534 may be disposed within an opening of the second conductive element 520. The first pole 532 may have a cross-sectional shape (e.g., a semi-elliptical cross-sectional shape) that is substantially similar to the shape of the first conductive element 510, and the second pole 534 may have a cross-sectional shape (e.g., a semi-elliptical cross-sectional shape) that is substantially similar to the shape of the second conductive element 520. Further, in the illustrated example, the first pole surface 542 can be substantially planar with the bottom surface 512 of the first conductive element 510, and the second pole surface 544 can be substantially planar with the bottom surface 522 of the second conductive element 520. However, in some examples, it should be recognized that the first pole surface 542 may extend beyond the plane of the bottom surface 512 of the first conductive element 510 and / or the second pole surface 544 may extend beyond the plane of the bottom surface 522 of the second conductive element 520.

[0092] Although not shown, in some examples, the ferromagnetic component 530 may be configured to be adjustable, for example, with respect to the biological structure of a subject's head (e.g., the curvature of the ferromagnetic component 530 may be adjustable). For example, the ferromagnetic component 530 may include a plurality of pieces, and one or more pieces of the ferromagnetic component 530 may be configured to be adjustable with respect to one or more other pieces of the ferromagnetic component 530, and / or two or more of the pieces of the ferromagnetic component 530 may be configured to be adjustable (e.g., pivotally adjustable) with respect to each other (e.g., through the use of a hinge between the pieces of the ferromagnetic component 530).

[0093] The treatment coil 500 can be configured to be driven so that the treatment coil 500 can be used to treat multiple (e.g., two) target areas of a subject. For example, during a treatment or diagnostic procedure, the bottom surface 533 of the main body portion 538 between the first pole 532 and the third pole 536 can be placed above the first target area, and the bottom surface 533 of the main body portion 538 between the third pole 536 and the second pole 534 can be placed above the second target area of the subject, so that the treatment coil 500 can be arranged. Thereafter, the treatment coil 500 can be driven by a drive circuit of a treatment system and / or a magnetic stimulation system. For example, when driven, the treatment coil 500 can be configured such that current circulates in the same direction (e.g., counterclockwise when viewed from the bottom perspective as shown in FIG. 5B) through the first and second conductive elements 510, 520.

[0094] As a result, the treatment coil 500 can be configured to generate magnetic fields that induce two activation zones, one for each of the target locations. The activation zones can each define a substantially semi-elliptical shape (e.g., a rounded rectangle) substantially below the bottom surface 533 of the main body portion 538, where the first activation zone is below the bottom surface 533 between the first pole 532 and the third pole 536, and the second activation zone is below the bottom surface 533 between the second pole 534 and the third pole 536. For example, the treatment coil 500 can also be configured to generate magnetic fields that induce two activation zones without inducing a stimulation zone in the area below the third pole surface 546. Further, the return current generated by the treatment coil 500 can be positioned at any end of the ferromagnetic component 530 (e.g., in proximity to the first and second poles 532, 534).

[0095] The treatment coil 500 can be configured such that when the first and second conductive elements 510, 520 are driven, the resulting activation zones include two independent areas within the subject's brain. The areas within the subject's brain can be correlated with different functional regions of the brain. For example, the treatment coil 500 can be used to stimulate two different areas within the subject's brain, such as a first area positioned below and proximate to the first pole face 542, and a second area positioned below and proximate to the second pole face 544. The currents in the two areas of the brain can move in the same or different directions (e.g., clockwise and / or counterclockwise). That is, in some examples, the two activation zones can include currents traveling in opposite (e.g., anti-parallel) directions.

[0096] In some examples, the ferromagnetic component 530 can define a third pole 536, which defines a third pole face 546, and it should be recognized that the third pole face 546 is trapezoidal or parallelogram-shaped. In such cases, the bottom surface 533 between the first pole 532 and the third pole 536, and the bottom surface 533 between the second pole 534 and the third pole 536 can have different shapes or sizes (e.g., the bottom surfaces 533 may not be mirror images of each other), which can adjust the magnetic field resulting from the treatment coil 500, and also the shape and / or size of the resulting activation zones. Thus, the shape of the third pole face 546 can be adjusted based on the specific treatment or diagnostic procedure performed by the treatment coil 500.

[0097] Furthermore, in some examples, it should be recognized that the ferromagnetic component 530 can be bent such that the first and second poles 532, 534 are brought closer together. In such cases, the bottom surfaces 533 between the first pole 532 and the third pole 536, and the bottom surfaces 533 between the second pole 534 and the third pole 536, can have different shapes or sizes (e.g., the bottom surfaces 533 may be non-mirror images of each other), which can adjust the magnetic field resulting from the treatment coil 500 and, also, the shape and / or size of the resulting activation zone. Further, when the ferromagnetic component 530 is bent in such a manner, the two resulting activation zones can include currents flowing in a direction that is exactly anti-parallel (e.g., opposite) compared to, for example, the illustrated example where the currents are flowing in a direction that is closer to anti-parallel.

[0098] The activation zones induced by the magnetic field generated by the treatment coil 500 can be stimulation zones or sub-stimulation zones. A stimulation zone can be at a level where the induced current caused by the pulsed magnetic field generated by the treatment coil 500 exceeds the depolarization threshold of the neurons in the brain, while a sub-stimulation zone can be at a level where the induced current is below the depolarization threshold of the neurons in the brain. Further, although two activation zones and two treatment areas have been described, the treatment coil 500 can be used to generate a magnetic field that induces more or fewer activation zones for more or fewer treatment areas of a patient (e.g., depending on a particular treatment or diagnostic procedure).

[0099] The treatment coil 500 can be configured such that the conductive elements 510, 520 and the ferromagnetic component 530 support each other. For example, the treatment coil 500 can be configured such that the ferromagnetic component 530 supports the conductive elements 510, 520. One or both of the conductive elements 510, 520 and the ferromagnetic component 530 can include one or more complementary attachment members (not shown), and the one or more complementary attachment members are configured to attach (e.g., releasably attach) the conductive elements 510, 520 to the ferromagnetic component 530. The one or more attachment members can be configured such that the conductive elements 510, 520 and the ferromagnetic component 530 are fixedly supported with respect to each other. The one or more attachment members can be configured such that the conductive elements 510, 520 and the ferromagnetic component 530 are movable (e.g., repositionable) with respect to each other.

[0100] When the conductive elements 510, 520 are supported (e.g., attached) by the ferromagnetic component 530, the conductive elements 510, 520 can be electrically isolated from the ferromagnetic component 530, for example, using a dielectric. The dielectric can be air, and when the conductive elements 510, 520 are attached to the ferromagnetic component 530, the conductive elements 510, 520 can be spaced apart from the ferromagnetic component 530 (e.g., not in direct contact with the ferromagnetic component 530). The conductive elements 510, 520 can be attached to the ferromagnetic component 530 using one or more attachment members made of any suitable electrically isolating (e.g., dielectric) material.

[0101] Figures 6A - 6D illustrate an exemplary treatment coil 600 configured to generate a varying magnetic field within a target biological structure of a subject, such as a human subject (not shown). The target biological structure of the subject can be, for example, the brain tissue of the subject. The treatment coil 600 includes a first conductive element 610, a second conductive element 620, a third conductive element 660, a fourth conductive element 670, a first ferromagnetic component 630, a second ferromagnetic component 680, and a third ferromagnetic component 690. The treatment coil 600 can be disposed proximate to the head of the subject, for example, for preparation for TMS treatment or during TMS treatment, as shown in FIG. 1. The combination of the conductive elements 610, 620, 660, 670 and the ferromagnetic components 630, 680, 690 can collectively be referred to as, for example, an electromagnet. It should be recognized that the treatment coil 600 can include more or fewer conductive elements and / or ferromagnetic components than those shown. The conductive element can be referred to as a conductive winding.

[0102] The first and second conductive elements 610, 620 may be semi - elliptical in shape (e.g., have a rounded rectangular shape). Further, in some examples, the first and second conductive elements 610, 620 can be of another shape, for example, circular in shape. In some examples, the first and second conductive elements 610, 620 can together form an eight - shaped coil or a B - shaped coil. The first conductive element 610 can define a bottom surface 612, an upper surface 614, an inner surface 616, and an outer surface 618. Similarly, the second conductive element 620 can define a bottom surface 622, an upper surface 624, an inner surface 626, and an outer surface 628. The first and second conductive elements 610, 620 can be made from any material exhibiting an appropriate electrical conductivity, such as, for example, copper.

[0103] The first and second conductive elements 610, 620 may define the same number of turns (e.g., amp turns), for example, a single turn as illustrated. However, in some examples, it should be recognized that the first conductive element 610 and / or the second conductive element 620 may define a plurality of turns. For example, in some examples, the first conductive element 610 may define a first number of turns, while the second conductive element 620 may define a different second number of turns. By defining more turns on one side (e.g., one of the conductive elements 610, 620) than the other, the treatment coil 600 can result in two activation zones having different intensities or depths (e.g., when each side is driven at the same power level). Further, in some examples, the treatment coil 600 may include additional conductive elements and / or conductive elements that define a plurality of loops (e.g., amp turns). For example, the first conductive element 610 may include one or more additional and overlapping conductive elements (e.g., the first conductive element 610 may define a plurality of loops), and / or the second conductive element 620 may include one or more additional and overlapping conductive elements (e.g., the second conductive element 620 may define a plurality of loops).

[0104] The first conductive element 610 and / or the second conductive element 620 may be formed from a single monolithic piece of conductive material, or one or more of the first and second conductive elements 610, 620 may be formed by a plurality of strands of wire. In some examples, the treatment coil 600 may include a housing (not shown) that houses the first and second conductive windings 610, 620 and the first ferromagnetic component 630.

[0105] The first ferromagnetic component 630 can be made from any material that exhibits suitable ferromagnetic properties, such as powdered ferromagnetic iron particles. The first ferromagnetic component 630 can include a main body portion 638 and a plurality of poles, such as a first pole 632, a second pole 634, and a third pole 636 that extend from, for example, the main body portion 638. Although illustrated as having three poles, in some examples, the first ferromagnetic component 630 can include more or fewer than three poles. The plurality of poles (e.g., the first, second, and third poles 632, 634, 636) can extend outwardly from the main body portion 638 (e.g., from the bottom surface 633 of the main body portion 638). The third pole 636 can be present between the first pole 632 and the second pole 634. For example, the first, second, and third poles 632, 634, 636 can be aligned linearly (e.g., as illustrated). However, it should be recognized that in some examples, one or more of the first, second, and / or third poles 632, 634, 636 can be aligned in a non-linear manner.

[0106] The main body portion 638 of the first ferromagnetic component 630 can define a top surface 631 and a bottom surface 633. The main body portion 638 can be curved, for example, as illustrated. For example, the top surface 631 of the main body portion 638 can define a convex surface, while the bottom surface 633 of the main body portion 638 can define a concave surface. Thus, the top surface 631 can be non-planar, and the bottom surface 633 can be non-planar. Further, it should be recognized that in some examples, the curvature of the top surface 631 and / or the bottom surface 633 of the main body portion 638 can define a greater or lesser curvature than that illustrated. Moreover, it should be recognized that in some examples, the top surface 631 and / or the bottom surface 633 of the main body portion 638 can be planar (e.g., flat).

[0107] The first pole 632 may define a first pole surface 642, the second pole 634 may define a second pole surface 644, and the third pole 636 may define a third pole surface 646. The first pole 632 may be disposed within an opening of the first conductive element 610, and the second pole 634 may be disposed within an opening of the second conductive element 620. The first pole 632 may have a cross-sectional shape (e.g., a semi-elliptical cross-sectional shape) that is substantially similar to the shape of the first conductive element 610, and the second pole 634 may have a cross-sectional shape (e.g., a semi-elliptical cross-sectional shape) that is substantially similar to the shape of the second conductive element 620. Further, in the illustrated example, the first pole surface 642 may be substantially planar with the bottom surface 612 of the first conductive element 610, and the second pole surface 644 may be substantially planar with the bottom surface 622 of the second conductive element 620. However, in some examples, it should be recognized that the first pole surface 642 may extend beyond the plane of the bottom surface 612 of the first conductive element 610 and / or the second pole surface 644 may extend beyond the plane of the bottom surface 622 of the second conductive element 620.

[0108] Although not shown, in some examples, the first ferromagnetic component 630 may be configured to be adjustable, for example, with respect to the biological structure of a subject's head (e.g., the curvature of the first ferromagnetic component 630 may be adjustable). For example, the first ferromagnetic component 630 may include a plurality of pieces, and one or more pieces of the first ferromagnetic component 630 may be configured to be adjustable with respect to one or more other pieces of the first ferromagnetic component 630, and / or two or more of the pieces of the first ferromagnetic component 630 may be configured to be adjustable (e.g., pivotally adjustable) with respect to each other (e.g., through the use of a hinge between the pieces of the first ferromagnetic component 630).

[0109] The third and fourth conductive elements 660, 670 may be semi-elliptical in shape (e.g., shaped like a rounded rectangle). Further, in some examples, the third and fourth conductive elements 660, 670 may have another shape, e.g., may be circular in shape. The third conductive element 660 may define an inner surface 662, an outer surface 664, an upper surface 663, and a bottom surface 665. Similarly, the fourth conductive element 670 can define an inner surface 672, an outer surface 674, an upper surface 673, and a bottom surface 675. The fourth conductive element 670 can be bent downward, for example, as shown. For example, the bottom surface 675 of the fourth conductive element 670 can be concave, while the upper surface 673 can be convex. However, in some examples, it should be recognized that one or more of the upper surface and / or bottom surface 673, 675 of the fourth conductive element 670 may be planar (e.g., the fourth conductive element 670 is not bent). Further, the fourth conductive element 670 may define a perimeter larger than that of the third conductive element 660. The third conductive element 600 may be at least partially present within the opening of the fourth conductive element 670. That is, the fourth conductive element 670 may surround (e.g., substantially) the third conductive element 660.

[0110] The third and fourth conductive elements 660, 670 can be made from any material that exhibits suitable electrical conductivity, such as copper. The third conductive element 660 and / or the fourth conductive element 670 can be formed from a single monolithic piece of conductive material, or one or more of the third and fourth conductive elements 660, 670 can be formed by a plurality of strands of wire. In some examples, the treatment coil 600 can include a housing (not shown) that houses the first, second, third, and fourth conductive elements 610, 620, 660, 670 as well as the first, second, and third ferromagnetic components 630, 680, and 690.

[0111] The third and fourth conductive elements 660, 670 can define the same number of turns (e.g., ampere-turns), e.g., a single turn as illustrated. However, it should be recognized that in some examples, the third conductive element 660 and / or the fourth conductive element 670 can define a plurality of turns. For example, in some examples, the third conductive element 660 can define a first number of turns, while the fourth conductive element 670 can define a different second number of turns.

[0112] The second and third ferromagnetic components 680, 690 can be made from any material that exhibits suitable ferromagnetic properties, such as powdered ferromagnetic iron particles. The second and third ferromagnetic components 680, 690 can be referred to as return path ferromagnetic components (e.g., return path magnetic cores). The second ferromagnetic component 680 can define a channel 682, a bottom surface 684, an inner surface 685, an upper surface 686, an outer surface 687, a first pole 688, and a second pole 689. Similarly, the third ferromagnetic component 690 can define a channel 692, a bottom surface 694, an inner surface 695, an upper surface 696, an outer surface 697, a first pole 698, and a second pole 699. Each of the bottom surfaces 684, 694, the upper surfaces 686, 696, the first poles 688, 698, and the second poles 689, 699 of the second and third ferromagnetic components 680, 690 may be planar. However, in some examples, it should be recognized that one or more of the bottom surfaces 684, 694, the upper surfaces 686, 696, the first poles 688, 698, and / or the second poles 689, 699 of the second and third ferromagnetic components 680, 690 may be curved or otherwise shaped.

[0113] The second and third ferromagnetic components 680, 690 may be curved. For example, the inner surfaces 685, 695 of the second and third ferromagnetic components 680, 690 can be concave, while the outer surfaces 687, 697 of the second and third ferromagnetic components 680, 690 can be convex. For example, the curvature of the inner and outer surfaces 685, 695, 687, 697 of the second and third ferromagnetic components can be substantially similar to the curvature of the inner and outer surfaces of the fourth conductive element 670. However, the curvature of the inner and outer surfaces 685, 695, 687, 697 of the second and third ferromagnetic components 680, 690 is not limited to that shown in FIGS. 6A - 6D.

[0114] The second and third ferromagnetic components 680, 690 can be substantially the same size and shape. However, in some examples, the second and third ferromagnetic components 680, 690 can have sizes and / or shapes different from those shown. Further, in some examples, the size or shape of the second ferromagnetic component 680 can be different from the size or shape of the third ferromagnetic component 690 (e.g., to shift the size and / or shape of the magnetic field generated by the treatment coil 600). Also, in some examples, one or both of the second or third ferromagnetic components 680, 690 can be omitted from the treatment coil 600.

[0115] The sizes (e.g., depths) and shapes of channels 682, 692 of the second and third ferromagnetic components 680, 690 can be configured such that a fourth conductive element 670 can be received within channels 682, 692. That is, channels 682, 692 can be sized and shaped such that at least a portion of the fourth conductive element 670 can be present within channels 682, 692. It should be appreciated that more or less of the fourth conductive element 670 can be present within channels 682, 692 than that shown in FIGS. 6A-6D. For example, channels 682, 692 can be configured such that the bottom surface 675 of the fourth conductive element 670 can be non-planar with the plane defined by the bottom surfaces 684, 694 of the second and third ferromagnetic components 680, 690 (e.g., the fourth conductive element 670 can extend beyond or out of channels 682, 692, as shown, for example). However, it should be appreciated that in some examples, channels 682, 692 can be configured such that the bottom surface 675 of the fourth conductive element 670 can be planar with the plane defined by the bottom surfaces 684, 694. Further, the second and third ferromagnetic components 680, 690 can enclose any portion of the fourth conductive element 670 (more or less than that shown in FIGS. 6A-6D, for example). For example, in some examples, the entire fourth conductive element 670 can be present within channels 682, 692 of the second and third ferromagnetic components 680, 690 (e.g., the second and third ferromagnetic components 680, 690 can be a single monolithic component).

[0116] Referring to FIGS. 6C-6D, the treatment coil 600 can be configured such that the third pole 636 of the first ferromagnetic component 630 is present within the opening of the third conductive element 660. For example, the third pole face 646 of the third pole 636 can be substantially planar with the bottom surface 665 of the third conductive element 660. However, in other examples, it should be recognized that the third pole face 646 may be non-planar with the bottom surface 665 of the third conductive element 660 (e.g., the third pole face 646 may extend through the third conductive element 660). Further, the third pole 636 can be (e.g., partially) present within the opening of the fourth conductive element 670. Thus, for example, as shown, the third and fourth conductive elements 660, 670 can be positioned such that the third pole 636 of the first ferromagnetic component 630 is present within the openings of both the third and fourth conductive elements 660, 670, and the third conductive element 660 is present within the opening of the fourth conductive element 670.

[0117] An area where the first, third, and fourth conductive elements 610, 660, 670 are close to each other (e.g., below the bottom surface 633 of the ferromagnetic component 630) can be installed above the first target area, and an area where the second, third, and fourth conductive elements 620, 660, 670 are close to each other (e.g., below the opposite bottom surface 633 of the first ferromagnetic component 630) can be installed above the second target area of the subject, so that the treatment coil 600 can be disposed. Thereafter, the treatment coil 600 can be driven by a drive circuit of a treatment system and / or a magnetic stimulation system. For example, when driven, a current circulates in the same direction (e.g., counterclockwise as viewed from the bottom perspective as shown in FIG. 6D) through the first and second conductive elements 610, 620, and a current circulates in the opposite direction (e.g., clockwise as viewed from the bottom perspective as shown in FIG. 6D) through the third and fourth conductive elements 660, 670, or vice versa, so that the treatment coil 600 can be configured.

[0118] As a result, the treatment coil 600 can be configured to generate a magnetic field that induces two activation zones, one for each of the target locations, where each of the activation zones has an elliptical shape (e.g., substantially below the area where the first, third, and fourth conductive elements 610, 660, 670 are close to each other, and substantially below the area where the second, third, and fourth conductive elements 620, 660, 670 are close to each other). For example, the treatment coil 600 can also be configured to generate a magnetic field that induces two activation zones without inducing a stimulation zone in the area below the third pole surface 646.

[0119] Including the third and fourth conductive elements 660, 670 and the second and third ferromagnetic components 680, 690 can act to spread the return current induced by the magnetic field generated by the treatment coil 600 (e.g., as compared to when any combination of the third and fourth conductive elements 660, 670 or the second and third ferromagnetic components 680, 690 is not included). Any combination of the third and fourth conductive elements 660, 670 and the second and third ferromagnetic components 680, 690 can be included within the treatment coil 600, for example, to further clarify or enhance two activation zones generated by the magnetic field (e.g., under the first and second target areas) and / or to prevent the two activation zones from merging into a single activation zone (e.g., a single oval or circular shaped activation zone under the third pole face 646). For example, including the third and fourth conductive elements 660, 670 can distort the magnetic field generated by the treatment coil 600 by spreading the return current to an area substantially below and proximate to the second and third ferromagnetic components 680, 690, and including the second and third ferromagnetic components 680, 690 can enhance this spread of the return current. For example, including the third and fourth conductive elements 660, 670 can pull the return current further away from the third pole face 646, for example, to enhance two activation zones and prevent a single activation zone (e.g., one large ring) from resulting. Further, including the third and fourth conductive elements 660, 670 can make the treatment coil 600 more energy efficient when generating two activation zones. And including the second and third ferromagnetic components 680, 690 can cause the return current to diverge away from the third pole face 646, which can enhance the current inside the two activation zones.

[0120] For further explanation, and to be applicable to any of the treatment coils described herein, when the conductive element of the treatment coil is driven, a loop of current can be generated through the conductive element. Since the loop of current changes over time (e.g., is pulsed), the loop of current can induce a current that opposes this change in another conductive element (e.g., it is a current driven in the opposite direction). The loop of current can have a shape similar to that of the conductive element, but the activation zone (and / or, e.g., the magnetic field caused by the loop of current) can have a shape different from that of the conductive element. For example, the activation zone can be generated when the current converges, which can produce an activation zone of higher current density and / or a larger electric field. The activation zone can be defined by how close the conductive elements are to each other and can be varied, for example, through the addition of one or more ferromagnetic components (and / or, e.g., one or more additional conductive elements). The ferromagnetic component can enhance the local magnetic field and the electric field, for example, by spreading the return current away from the area between two activation zones.

[0121] For example, and with particular reference to FIG. 6D, the ferromagnetic components 630 may enhance or further clarify the two activation zones generated when driving the treatment coil 600. That is, the ferromagnetic components 680, 690 may enhance the electric field by drawing the return current towards each ferromagnetic component 680, 690 as the return current leaves the activation zone (e.g., causing the return current to spread away from the third pole surface 646). The reason is, for example, that the return current takes the path of least resistance. Without the ferromagnetic components 680, 690, the return current may take a shorter path, e.g., the path defined by the conductive element 660. Thus, the ferromagnetic components 680, 690 may help ensure that the two activation zones do not combine (e.g., fuse) into one large activation zone (e.g., a single activation zone including the area under the third pole surface 646).

[0122] The treatment coil 600 may be configured such that when the conductive elements 610, 620, 660, 670 are driven, the resulting activation zones encompass two independent areas within the subject's brain. The areas within the subject's brain may be correlated with different functional regions of the brain. For example, the treatment coil 600 may be used to stimulate two different areas within the subject's brain, e.g., a first area positioned below and proximate to the first pole surface 642 of the first ferromagnetic component 630, and a second area positioned below and proximate to the second pole surface 644. The currents in the two areas of the brain may move in the same or different directions (e.g., clockwise and / or counterclockwise).

[0123] The activation zone induced by the magnetic field generated by the treatment coil 600 can be a stimulation zone or a sub-stimulation zone. The stimulation zone can be at a level where the induced current caused by the pulsed magnetic field generated by the treatment coil 600 exceeds the depolarization threshold of the neurons in the brain, while the sub-stimulation zone can be at a level where the induced current is below the depolarization threshold of the neurons in the brain. Further, although two activation zones and two treatment areas have been described, the treatment coil 600 can be used to generate a magnetic field that induces more or fewer activation zones for more or fewer treatment areas of the patient (e.g., depending on a particular treatment or diagnostic procedure).

[0124] Furthermore, in some examples, it should be recognized that the treatment coil 600 can include additional conductive elements that can be located around the third conductive element 660 (and / or, for example, the third and / or fourth conductive elements 660, 670 can include additional turns (e.g., amplifier turns)). Additionally, in some examples, the second ferromagnetic component 680 and / or the third ferromagnetic component 690 can be shaped such that it covers both the third and fourth conductive elements 660, 670. For example, the upper surfaces 686, 696 of the second and third ferromagnetic components 680, 690 can extend above the upper surface 663 of the third conductive element 660.

[0125] The treatment coil 600 can be configured such that the conductive elements 610, 620, 660, 670 and the ferromagnetic components 630, 680, 690 support each other. For example, one or more of the conductive elements 610, 620, 660, 670 and the ferromagnetic components 630, 680, 690 may include one or more complementary attachment members (not shown), and the one or more complementary attachment members are configured to attach (e.g., removably attach) the conductive elements 610, 620, 660, 670 to the ferromagnetic components 630, 680, 690. The one or more attachment members can be configured such that the conductive elements 610, 620, 660, 670 and the ferromagnetic components 630, 680, 690 are fixedly supported with respect to each other. The one or more attachment members can be configured such that the conductive elements 610, 620, 660, 670 and the ferromagnetic components 630, 680, 690 are movable relative to each other (e.g., repositionable).

[0126] When the conductive elements 610, 620, 660, 670 are supported by (e.g., attached to) one or more of the ferromagnetic components 630, 680, 690, the conductive elements 610, 620, 660, 670 can be electrically isolated from the ferromagnetic components 630, 680, 690, for example, using a dielectric. The dielectric can be air, and when the conductive elements 610, 620, 660, 670 are attached to the ferromagnetic components 630, 680, 690, the conductive elements 610, 620, 660, 670 can be spaced from the ferromagnetic components 630, 680, 690 (e.g., not in direct contact with the ferromagnetic components 630, 680, 690). The conductive elements 610, 620, 660, 670 can be attached to one or more of the ferromagnetic components 630, 680, 690 using one or more attachment members made of any suitable electrically isolating (e.g., dielectric) material.

[0127] Figures 7A-7D illustrate an exemplary treatment coil 700 configured to generate a varying magnetic field within a target biological structure of a subject, such as a human subject (not shown). The target biological structure of the subject can be, for example, the subject's brain tissue. The treatment coil 700 includes a first pair of conductive elements 710a, 710b, a second pair of conductive elements 720a, 720b, a third pair of conductive elements 760a, 760b, a fourth pair of conductive elements 770a, 770b, a fifth pair of conductive elements 750a, 750b, a first ferromagnetic component 730, a second ferromagnetic component 780, a third ferromagnetic component 790, a fourth ferromagnetic component 745a, and a fifth ferromagnetic component 745b. The treatment coil 700 can be disposed proximate to the subject's head, for example, for preparation of TMS treatment or during TMS treatment, as shown in FIG. 1. The combination of conductive elements 710a / b, 720a / b, 750a / b, 760a / b, 770a / b and ferromagnetic components 730, 745a / b, 780, 790 can collectively be referred to as, for example, an electromagnet. It should be recognized that the treatment coil 700 can include more or fewer conductive elements and / or ferromagnetic components than shown. The conductive elements can be referred to as conductive windings.

[0128] Figures 7A-7B illustrate perspective views of the treatment coil 700, while FIGS. 7C-7D illustrate side views of the treatment coil 700 with the fourth and fifth ferromagnetic components 750, 755 in two different positions. The conductive elements of the first, second, third, fourth, and fifth pairs of conductive elements 710a / b, 720a / b, 760a / b, 770a / b, 750a / b can be made of any material exhibiting suitable electrical conductivity, such as, for example, copper. Further, the conductive elements of the first, second, third, fourth, and fifth pairs of conductive elements 710a / b, 720a / b, 760a / b, 770a / b, 750a / b can be parallel to each other (e.g., the upper surface and / or bottom surface of the first conductive element 710a can be parallel to the upper surface and / or bottom surface of the first conductive element 710b, etc.). However, in some examples, it should be recognized that any one or more of the pairs of conductive elements 710a / b, 720a / b, 760a / b, 770a / b, 750a / b can be non-parallel.

[0129] The conductive elements of the first and second pairs of conductive elements 710a, 710b, 720a, 720b may be semi-elliptical in shape (e.g., may have a rounded rectangular shape). Further, in some examples, the first and second pairs of conductive elements 710a, 710b, 720a, 720b can be of another shape, for example, may be circular in shape. The first conductive element 710a may define a bottom surface, an upper surface 714a, an inner surface 716a, and an outer surface 718a. Similarly, the first conductive element 710b may define a bottom surface 712b, an upper surface, an inner surface 716b, and an outer surface 718b. Further, the second conductive element 720a may define a bottom surface, an upper surface 724a, an inner surface 726a, and an outer surface 728a. And the conductive element 722b may define a bottom surface 722b, an upper surface, an inner surface 726b, and an outer surface 728b.

[0130] The conductive elements of the third pair of conductive elements 760a, 760b can be shaped by a rounded square (e.g., substantially the same shape as the third pole surface 746). Further, in some examples, the conductive elements of the third pair of conductive elements 760a, 760b can have another shape, for example, the shape can be circular or the like. The third conductive element 760a can define an inner surface 762a, an outer surface 764a, an upper surface 763a, and a bottom surface, while the third conductive element 760b can define an inner surface 762b, an outer surface 764b, an upper surface, and a bottom surface 765b.

[0131] Each of the conductive elements of the fourth and fifth pairs of conductive elements 770a, 770b, 750a, 750b can be semi-elliptical in shape (e.g., can be shaped like a rounded rectangle). Further, in some examples, the conductive elements of the fourth and fifth pairs of conductive elements 770a, 770b, 750a, 750b can have another shape, for example, the shape can be circular or the like. The fourth conductive element 770a can define an inner surface 772a, an outer surface 774a, an upper surface 773a, and a bottom surface. Similarly, the fourth conductive element 770b can define an inner surface 772b, an outer surface 774b, an upper surface, and a bottom surface 775b. Further, the fifth conductive element 750a can define an inner surface 752a, an outer surface 754a, an upper surface 753a, and a bottom surface 755a. And the fifth conductive element 750b can define an inner surface 752b, an outer surface 754b, an upper surface, and a bottom surface 755b.

[0132] The upper and bottom surfaces of the conductive elements of the third pair of conductive elements 760a, 760b may be planar (e.g., flat). Similarly, the upper and bottom surfaces of the conductive elements of the fourth and fifth pairs of conductive elements 770a, 770b, 750a, 750b may be planar (e.g., flat). However, in some examples, it should be recognized that one or more of the conductive elements of the third, fourth, or fifth pairs of conductive elements 760a, 760b, 770a, 770b, 750a, 750b can be bent or curved (e.g., bent downward). For example, the bottom surface of any of the conductive elements of the third, fourth, and fifth pairs of conductive elements 760a, 760b, 770a, 770b, 750a, 750b can be concave, while the upper surface of any of the conductive elements of the third, fourth, and fifth pairs of conductive elements 760a, 760b, 770a, 770b, 750a, 750b can be convex. Such curvature can be designed so that the treatment coil 700 better conforms to the target biological structure (e.g., the curvature of a human head).

[0133] Furthermore, the fifth pair of conductive elements 750a / b may define a perimeter that is larger than that of the third pair of conductive elements 760a / b, and the fourth pair of conductive elements 770a / b may define a perimeter that is larger than that of the fifth pair of conductive elements 750a / b. The third conductive element 760a may be at least partially present within the openings of the fifth conductive element 750a and the fourth conductive element 770a, while the third conductive element 770b may be at least partially present within the openings of the fifth conductive element 750b and the fourth conductive element 770b. Further, the fifth conductive element 750a may be at least partially present within the opening of the fourth conductive element 770a, while the fifth conductive element 750b may be at least partially present within the opening of the fourth conductive element 770b. Thus, the fourth conductive element 770a may (e.g., substantially) surround the fifth conductive element 750a and the third conductive element 760a, while the fourth conductive element 770b may (e.g., substantially) surround the fifth conductive element 750b and the third conductive element 760b.

[0134] Each of the conductive elements of the first and second pairs of conductive elements 710a, 710b, 720a, 720b may define the same number of turns (e.g., amp-turns), e.g., a single turn as illustrated. However, it should be recognized that in some examples, any one or more of the conductive elements of the first and second pairs of conductive elements 710a, 710b, 720a, 720b may define multiple turns. Further, in some examples, the treatment coil 700 may include additional conductive elements and / or conductive elements that define multiple loops (e.g., amp-turns).

[0135] Each of the conductive elements of the first and second pairs of conductive elements 710a, 710b, 720a, 720b can be formed from a single monolithic piece of conductive material, or one or more of the conductive elements of the first and second pairs of conductive elements 710a, 710b, 720a, 720b can be formed by a plurality of strands of wire. In some examples, the treatment coil 700 can include a housing (not shown) that houses the first, second, third, fourth, and fifth pairs of conductive elements 710a / b, 720a / b, 760a / b, 770a / b, 750a / b as well as the first, second, third, fourth, and fifth ferromagnetic components 730, 780, 780, 745a, 745b.

[0136] The planes defined by the upper surfaces of the first to fifth conductive elements 710a, 720a, 760a, 770a, 750a can be substantially planar with respect to each other. Similarly, the planes defined by the bottom surfaces of the first to fifth conductive elements 710a, 720a, 760a, 770a, 750a can be substantially planar with respect to each other. However, in some examples, it should be recognized that the upper surfaces of any combination of the conductive elements 710a, 720a, 760a, 770a, 750a, and / or the bottom surfaces of any combination of the conductive elements 710b, 720b, 760b, 770b, 750b may be non-planar with respect to each other. For example, any one or more of the conductive elements 710a / b, 720a / b, 760a / b, 770a / b, 750a / b can be shifted such that its upper surface and / or bottom surface is non-planar with respect to the upper surface and / or bottom surface of each of the other conductive elements 710a / b, 720a / b, 760a / b, 770a / b, 750a / b. For example, in some examples, the fourth conductive element 750b can be made larger such that the bottom surface 775b of the fourth conductive element 750b can be non-planar with respect to the bottom surfaces of the other conductive elements (and can be planar with respect to the bottom surfaces 784, 794 of, for example, one or both of the second and third ferromagnetic components 780, 790).

[0137] The first ferromagnetic component 730 can be made from any material exhibiting suitable ferromagnetic properties, such as powdered ferromagnetic iron particles. The first ferromagnetic component 730 can include a main body portion 738 and a plurality of poles, which can be, for example, a first pole 732, a second pole 734, and a third pole 736 that extend from the main body portion 738. Although illustrated as having three poles, in some examples, the first ferromagnetic component 730 can include more or fewer than three poles. The plurality of poles (e.g., the first, second, and third poles 732, 734, 736) can extend outwardly from the main body portion 738 (e.g., from the bottom surface 733 of the main body portion 738). The third pole 736 can be present between the first pole 732 and the second pole 734. For example, the first, second, and third poles 732, 734, 736 can be linearly aligned (e.g., as illustrated). However, it should be recognized that in some examples, one or more of the first, second, and / or third poles 732, 734, 736 can be aligned in a non-linear manner.

[0138] The main body portion 738 of the first ferromagnetic component 730 can define a top surface 731 and a bottom surface 733. The top surface 731 and / or the bottom surface 733 of the main body portion 738 can be planar (e.g., flat). However, it should be recognized that in some examples, the main body portion 738 can be curved, such as illustrated by the first ferromagnetic component 630 of the treatment coil 600.

[0139] The first pole 732 may define a first pole face 742, the second pole 734 may define a second pole face 744, and the third pole 736 may define a third pole face 746. The first pole 732 may be disposed within the openings defined by each of the first conductive elements 710a / b, the second pole 734 may be disposed within the openings defined by each of the second conductive elements 720a / b, and the third pole may be disposed within the openings defined by each of the third conductive elements 760a / b. Further, the third pole 736 may also be (e.g., partially) present within the openings of the fourth and fifth conductive elements 770a / b, 750a / b. Thus, the third, fourth, and fifth conductive elements 760a / b, 770a / b, 750a / b may be positioned such that the third pole 736 of the first ferromagnetic component 730 is present within the openings of the third, fourth, and fifth conductive elements 760a / b, 770a / b, 750a / b.

[0140] The first pole 732 may have a cross-sectional shape (e.g., a semi-elliptical cross-sectional shape) that is substantially similar to the shape of each of the first conductive elements 710a / b, the second pole 734 may have a cross-sectional shape (e.g., a semi-elliptical cross-sectional shape) that is substantially similar to the shape of each of the second conductive elements 720a / b, and the third pole 736 may have a cross-sectional shape (e.g., a cross-sectional shape substantially square-shaped with rounded corners) that is substantially similar to the shape of each of the third conductive elements 760a / b.

[0141] Furthermore, in the illustrated example, the first pole surface 742 can be substantially planar with the bottom surface 712b of the first conductive element 710b, the second pole surface 744 can be substantially planar with the bottom surface 722b of the second conductive element 720b, and the third pole surface 746 can be substantially planar with the bottom surface 762b of the third conductive element 760b. However, in some examples, it should be recognized that the first pole surface 742 can extend beyond the plane of the bottom surface 712b of the first conductive element 710b, the second pole surface 744 can extend beyond the plane of the bottom surface 722b of the second conductive element 720b, and / or the third pole surface 746 can extend beyond the plane of the bottom surface 762b of the third conductive element 760b.

[0142] The second and third ferromagnetic components 780, 790 can be made from any material exhibiting suitable ferromagnetic properties, such as powdered ferromagnetic iron particles. The second ferromagnetic component 780 can define a bottom surface 784, an inner surface 785, an upper surface 786, an outer surface 787, a first pole 788, and a second pole 789. Similarly, the third ferromagnetic component 790 can define a bottom surface 794, an inner surface 795, an upper surface 796, an outer surface 797, a first pole 798, and a second pole 799. Each of the bottom surfaces 784, 794, the upper surfaces 786, 796, the first poles 788, 798, and the second poles 789, 799 of the second and third ferromagnetic components 780, 790 can be planar (e.g., flat). However, in some examples, it should be recognized that one or more of the bottom surfaces 784, 794, the upper surfaces 786, 796, the first poles 788, 798, and the second poles 789, 799 of the second and third ferromagnetic components 780, 790 can be curved or otherwise shaped.

[0143] The upper surfaces 786, 796 of the second and third ferromagnetic components 780, 790 can be planar with the upper surface 776a of the fourth conductive element 770a. However, the bottom surfaces 784, 794 of the second and third ferromagnetic components 780, 790 can extend beyond the plane defined by the bottom surface 777b of the fourth conductive element 770b (e.g., the bottom surfaces 784, 794 may be non-planar with the bottom surface 777b). However, in some examples, it should be recognized that one or more of the upper surfaces 786, 796 and / or the bottom surfaces 784, 794 may not be planar with the upper and / or bottom surfaces of the fourth conductive elements 770a, 770b, respectively.

[0144] The second and third ferromagnetic components 780, 790 may be curved. For example, the inner surfaces 785, 795 of the second and third ferromagnetic components 780, 790 can be concave, while the outer surfaces 787, 797 can be convex. For example, the curvature of the inner and outer surfaces 785, 795, 787, 797 of the second and third ferromagnetic components can be substantially the same as the curvature of the outer surface of the fourth conductive element 770a / b. However, the curvature of the inner and outer surfaces 785, 795, 787, 797 of the second and third ferromagnetic components 780, 790 is not limited to that shown in FIGS. 7A-7D.

[0145] The second and third ferromagnetic components 780, 790 can be substantially the same size and shape. However, in some examples, the second and third ferromagnetic components 780, 790 can have sizes and / or shapes different from those shown. Further, in some examples, the size or shape of the second ferromagnetic component 780 can be different from the size or shape of the third ferromagnetic component 790 (e.g., to shift the size and / or shape of the magnetic field generated by the treatment coil 700). Also, in some examples, one or both of the second or third ferromagnetic components 780, 790 can be omitted from the treatment coil 700.

[0146] The first and second pole faces 788, 789, 798, 799 of the second and third ferromagnetic components 780, 790 can each be perpendicular to the other surfaces of the second and third ferromagnetic components 780, 790. However, it should be recognized that in some examples, the first and second pole faces 788, 789, 798, 799 can be angled. For example, any one or more of the first and second pole faces 788, 789, 798, 799 can each form an acute or obtuse angle with any one or more of the other surfaces of the second and third ferromagnetic components 780, 790. For example, the first and second pole faces 788, 799 can form an obtuse angle with the upper surface 786 of the second ferromagnetic component 780 and an acute angle with the bottom surface 784 of the second ferromagnetic component 780.

[0147] The fourth and fifth ferromagnetic components 745a, 745b can be made of any material exhibiting appropriate ferromagnetic properties, such as powdered ferromagnetic iron particles. The fourth ferromagnetic component 745a can define an inner surface 746a, an outer surface, an upper surface, a left surface, and a right surface, as well as a bottom surface that defines a pole 749a. Similarly, the fifth ferromagnetic component 745b can define an inner surface, an outer surface 747b, an upper surface, a left surface, and a right surface, as well as a bottom surface that defines a pole 749b. The upper surfaces of the fourth and fifth ferromagnetic components 745a, 745b can each have the same size and shape (e.g., the same size and shape) as the first and second pole faces 742, 744. Further, the upper surfaces of the fourth and fifth ferromagnetic components 745a, 745b can each be parallel to the first and second pole faces 742, 744. When the treatment coil 700 is in use, the upper surfaces of the fourth and fifth ferromagnetic components 745a, 745b can each be installed close to (and, for example, potentially fixed to) the first and second pole faces 742, 744.

[0148] The poles 749a / b of the fourth and fifth ferromagnetic components 745a, 745b may be angled. For example, the pole face 749a of the fourth ferromagnetic component 745a can form an obtuse angle with the inner surface 746a of the fourth ferromagnetic component 745a and an acute angle with the outer surface of the fourth ferromagnetic component 745a. Similarly, the pole face 749b of the fifth ferromagnetic component 745b can form an obtuse angle with the inner surface of the fifth ferromagnetic component 745b and an acute angle with the outer surface 747b of the fifth ferromagnetic component 745b.

[0149] In some examples, the fourth and fifth ferromagnetic components 745a, 745b may be omitted from the treatment coil 700, or may be replaced with other ferromagnetic components of any desired size and shape, such as the sixth and seventh ferromagnetic components 745c, 745d illustrated in FIG. 7D. The inner and outer surfaces of the sixth and seventh ferromagnetic components 745c, 745d need not be perpendicular to the upper surface of the sixth and seventh ferromagnetic components 745c, 745d (for example, on the one hand, the inner and outer surfaces of the fourth and fifth ferromagnetic components 745a, 745b may be perpendicular to the upper surface of the fourth and fifth ferromagnetic components 745a, 745b). The sixth and seventh ferromagnetic components 745c, 745d may be shaped differently from the fourth and fifth ferromagnetic components 745a, 745b, such that the magnetic field generated by the treatment coil 700 may include an electric field within treatment areas having different shapes.

[0150] An area where the first conductive element 710b, the third conductive element 760b, the fourth conductive element 770b, and the fifth conductive element 750b are close to each other (e.g., below the bottom surface 733 of the ferromagnetic component 730) can be installed above the first target area, and an area where the second conductive element 720b, the third conductive element 760b, the fourth conductive element 770b, and the fifth conductive element 750b are close to each other (e.g., below the opposite bottom surface 733 of the ferromagnetic component 730) can be installed above the second target area of the subject, so that the treatment coil 700 can be disposed. Thereafter, the treatment coil 700 can be driven by a drive circuit of a treatment system and / or a magnetic stimulation system. For example, when driven, current circulates in the same direction (e.g., clockwise when viewed from the lower perspective as shown in FIG. 7B) through the first and second conductive elements 710a / b, 720a / b, and current circulates in the opposite direction (e.g., counterclockwise when viewed from the lower perspective as shown in FIG. 7B) through the third, fourth, and fifth conductive elements 760a / b, 770a / b, 750a / b, or vice versa, so that the treatment coil 700 can be configured.

[0151] As a result, the treatment coil 700 can be configured to generate a magnetic field that induces two activation zones, one at each of the target locations, where each of the activation zones has an elliptical shape (e.g., substantially below the area where the first conductive element 710b, the third conductive element 760b, the fourth conductive element 770b, and the fifth conductive element 750b are in proximity to each other, and substantially below the area where the second conductive element 720b, the third conductive element 760b, the fourth conductive element 770b, and the fifth conductive element 750b are in proximity to each other). For example, the treatment coil 700 can also be configured to generate a magnetic field that induces two activation zones without inducing a stimulation zone in the area below the third pole face 746.

[0152] Including the third, fourth, and fifth conductive elements 760a / b, 770a / b, 750a / b and the second and third ferromagnetic components 780, 790 can act to spread the return current caused by the magnetic field generated by the treatment coil 700 (e.g., as compared to a treatment coil 700 that does not include the third, fourth, and / or fifth conductive elements 760a / b, 770a / b, 750a / b and does not include the second and / or third ferromagnetic components 780, 790). Any combination of the third, fourth, and fifth conductive elements 760a / b, 770a / b, 750a / b and the second and third ferromagnetic components 780, 790 can be included in the treatment coil 700, for example, to further clarify or enhance two activation zones generated by the magnetic field (e.g., under the first and second target areas), and / or to prevent the two activation zones from merging into a single activation zone (e.g., a single oval or circular-shaped activation zone under the third pole face 746). For example, including the third, fourth, and fifth conductive elements 760a / b, 770a / b, 750a / b distorts the magnetic field generated by the treatment coil 700 by spreading the return current to an area substantially below and adjacent to the second and third ferromagnetic components 780, 790, and including the second and third ferromagnetic components 780, 790 further enhances this spread of the return current. For example, including the third, fourth, and fifth conductive elements 760a / b, 770a / b, 750a / b pulls the return current further away from the third pole face 746, for example, can enhance two activation zones and prevent a single activation zone (e.g., one large ring) from resulting. Further, including the third and fourth conductive elements 660, 670 can make the treatment coil 600 more energy efficient when generating two activation zones.Including the second and third ferromagnetic components 780, 790 may cause the return current to diverge away from the third pole face 746, which may enhance the current inside the two activation zones.

[0153] Stated in another way, the ferromagnetic components 780, 790 can enhance the electric field generated by the treatment coil 700 by drawing the return current towards each ferromagnetic component 780, 790 when the return current leaves the activation zone (e.g., spreading the return current away from the third pole face 746). The reason is that, for example, the return current takes the path of least resistance. Without the ferromagnetic components 780, 790, the return current may take a shorter path, e.g., the path defined by the conductive element 760. Therefore, the ferromagnetic components 780, 790 may help ensure that the two activation zones do not combine (e.g., fuse) into one large activation zone (e.g., a single activation zone including the area under the third pole face 746).

[0154] Furthermore, including fourth and fifth ferromagnetic components 745a, 745b (or, for example, ferromagnetic components of different sizes and / or shapes adjacent to the first and second pole faces 742, 744 of the first ferromagnetic component 730) can enable the treatment coil 700 to shift the relative locations of the two activation zones and / or adjust the shapes of the two activation zones. For example, a shift in the relative locations and / or shapes of the two activation zones may be desirable when treating a patient (where the patient's target biological structure (e.g., the head) is of different sizes and / or shapes). As a further example, a shift in the relative locations and / or shapes of the two activation zones may be desirable during different treatment and / or diagnostic procedures (e.g., when the target locations associated with the two activation zones change). The ability to configure the treatment coil 700 in this way allows the coil 700 to be optimized for different patients and / or different treatment / diagnostic procedures.

[0155] The treatment coil 700 can be configured such that when the conductive elements 710a / b, 720a / b, 760a / b, 770a / b, 750a / b are driven, the resulting activation zones encompass two independent areas within the subject's brain. The areas within the subject's brain can be correlated with different functional regions of the brain. For example, the treatment coil 700 can be used to stimulate two different areas within the subject's brain, such as, for example, a first area positioned below and adjacent to the pole face 749a of the fourth and fifth ferromagnetic components 745a, 745b, respectively, and a second area positioned below and adjacent to the second pole face 749b. The currents in the two areas of the brain can move in the same direction or different directions (e.g., clockwise and / or counterclockwise).

[0156] Activation induced by the magnetic field generated by the treatment coil 700 can be a stimulation zone or a sub-stimulation zone. The stimulation zone can be at a level where the induced current caused by the pulsed magnetic field generated by the treatment coil 700 exceeds the depolarization threshold of the neurons in the brain, while the sub-stimulation zone can be at a level where the induced current is below the depolarization threshold of the neurons in the brain. Further, although two activation zones and two treatment areas have been described, the treatment coil 700 can be used to generate a magnetic field that induces more or fewer activation zones for more or fewer treatment areas of the patient (e.g., depending on a particular treatment or diagnostic procedure).

[0157] The treatment coil 700 can be configured such that the conductive elements 710a / b, 720a / b, 760a / b, 770a / b, 750a / b and the ferromagnetic components 730, 780, 790, 745a, 745b support each other. For example, one or more of the conductive elements 710a / b, 720a / b, 760a / b, 770a / b, 750a / b and the ferromagnetic components 730, 780, 790, 745a, 745b can be one or more complementary attachment members (not shown), and the one or more complementary attachment members are configured to enable attachment (e.g., releasable attachment) of the conductive elements 710a / b, 720a / b, 760a / b, 77a / b, 750a / b to the ferromagnetic components 730, 780, 790, 745a, 745b. The one or more attachment members can be configured such that the conductive elements 710a / b, 720a / b, 760a / b, 77a / b, 750a / b and the ferromagnetic components 730, 780, 790, 745a, 745b are fixedly supported with respect to each other. The one or more attachment members can be configured such that the conductive elements 710a / b, 720a / b, 760a / b, 77a / b, 750a / b and the ferromagnetic components 730, 780, 790, 745a, 745b are movable (e.g., repositionable) with respect to each other.

[0158] When the conductive elements 710a / b, 720a / b, 760a / b, 77a / b, 750a / b are supported by (e.g., attached to) one or more of the ferromagnetic components 730, 780, 790, 745a, 745b, the conductive elements 710a / b, 720a / b, 760a / b, 77a / b, 750a / b can be electrically isolated from the ferromagnetic components 730, 780, 790, 745a, 745b, for example, using a dielectric. The dielectric can be air, and when the conductive elements 710a / b, 720a / b, 760a / b, 77a / b, 750a / b are attached to the ferromagnetic components 730, 780, 790, 745a, 745b, the conductive elements 710a / b, 720a / b, 760a / b, 77a / b, 750a / b can be spaced apart from the ferromagnetic components 730, 780, 790, 745a, 745b (e.g., not in direct contact with the ferromagnetic components 730, 780, 790, 745a, 745b). The conductive elements 710a / b, 720a / b, 760a / b, 77a / b, 750a / b can be attached to one or more of the ferromagnetic components 730, 780, 790, 745a, 745b using one or more attachment members made of any suitable electrically isolating (e.g., dielectric) material.

[0159] Figures 8A and 8B illustrate an exemplary treatment coil 800 configured to generate a changing magnetic field within a target biological structure of a subject, such as a human subject (not shown). The target biological structure of the subject can be, for example, the brain tissue of the subject. The treatment coil 800 includes a first conductive element 810, a second conductive element 820, and a ferromagnetic component 830. The treatment coil 800 can be disposed proximate to the head of the subject, for example, for preparation for TMS treatment or during TMS treatment, as shown in FIG. 1. The combination of the conductive elements 810, 820, and the ferromagnetic component 830 can collectively be referred to as, for example, an electromagnet. It should be recognized that the treatment coil 800 can include more or fewer conductive elements than shown. The conductive elements can be referred to as conductive windings.

[0160] The first and second conductive elements 810, 820 may be semi-elliptical in shape (e.g., having a rounded square cross-section). Further, in some examples, the first and second conductive elements 810, 820 may be of another shape, for example, may be circular in shape. In some examples, the first and second conductive elements 810, 820 may together form an 8-shaped coil or a B-shaped coil. The first conductive element 810 may define an upper surface 812 and a bottom surface 814. Similarly, the second conductive element 820 may define an upper surface 822 and a bottom surface 824. The upper surfaces 812, 822 may be rounded. For example, the upper surfaces 812, 822 may be convex in shape. The bottom surfaces 814, 824 may be arched. For example, the bottom surfaces 814, 824 may be concave in shape. Although shown as convex and concave in shape, any one or more of the upper and bottom surfaces of the first and second conductive elements 810, 820 may be planar (e.g., flat). Further, in such examples, the first and / or second conductive elements 810, 820 may define one or more sides. The first and second conductive elements 810, 820 may be made of any material exhibiting suitable electrical conductivity, such as, for example, copper.

[0161] The first and second conductive elements 810, 820 may define the same number of turns (e.g., amp-turns), for example, a single turn as illustrated. However, in some examples, it should be recognized that the first conductive element 810 and / or the second conductive element 820 may define a plurality of turns. For example, in some examples, the first conductive element 810 may define a first number of turns, while the second conductive element 820 may define a different second number of turns. Further, in some examples, the treatment coil 800 may include additional conductive elements and / or conductive elements that define a plurality of loops (e.g., amp-turns). For example, the first conductive element 810 may include one or more additional and overlapping conductive elements (e.g., the first conductive element 810 may define a plurality of loops), and / or the second conductive element 820 may include one or more additional and overlapping conductive elements (e.g., the second conductive element 820 may define a plurality of loops).

[0162] The first conductive element 810 and / or the second conductive element 820 may be formed from a single monolithic piece of conductive material, or one or more of the first and second conductive elements 810, 820 may be formed by a plurality of strands of wire. In some examples, the treatment coil 800 may include a housing (not shown) that houses the first and second conductive windings 810, 820 and the ferromagnetic component 830.

[0163] The ferromagnetic component 830 can be made from any material that exhibits suitable ferromagnetic properties, such as powdered ferromagnetic iron particles. The ferromagnetic component 830 can include a main body portion 838 and a plurality of poles, and the plurality of poles can be, for example, a first pole 834, a second pole 836, a third pole 838, and a fourth pole 840 that extend from the main body portion 832. Although it is illustrated as having four poles, in some examples, the ferromagnetic component 830 can include more or fewer than four poles. The second pole 836 can be present between the first pole 834 and the fourth pole 840, and the fourth pole 810 can be present between the second pole 836 and the third pole 838. For example, the first, second, third, and fourth poles 834, 836, 838, 840 can be aligned linearly (as illustrated, for example). However, it should be recognized that in some examples, one or more of the first, second, third, and fourth poles 834, 836, 838, 840 can be aligned in a non-linear manner.

[0164] The first pole 834 and the third pole 838 can extend outwardly from the main body portion 832 (for example, from the bottom surface 843 of the main body portion 832). The second pole 836 can extend from the first pole 834 (for example, can extend from the inside of the first pole 834), and the fourth pole 840 can extend from the third pole 838 (for example, can extend from the inside of the third pole 838). However, it should be recognized that in some examples, one or more of the second and fourth poles 836, 840 can extend outwardly from the main body portion 832 (for example, from the bottom surface 843 of the main body portion 832).

[0165] The main body portion 832 of the ferromagnetic component 830 may define an upper surface 842 and a bottom surface 843. The main body portion 832 may be curved, for example, as illustrated. For example, the upper surface 842 of the main body portion 832 may define a convex surface, while the bottom surface 843 of the main body portion 832 may define a concave surface. Thus, the upper surface 842 may be non-planar, and the bottom surface 843 may also be non-planar. Further, in some examples, it should be recognized that the curvature of the upper surface 842 and / or the bottom surface 843 of the main body portion 832 may define a curvature that is greater or less than that illustrated. Moreover, in some examples, it should be recognized that the upper surface 842 and / or the bottom surface 843 of the main body portion 832 may be planar (e.g., flat).

[0166] The first pole 834 may define a first pole face 844, the second pole 836 may define a second pole face 846, the third pole 838 may define a third pole face 848, and the fourth pole 840 may define a fourth pole face 850. The first pole face 844 and the third pole face 848 may define concave surfaces (e.g., having a concave curvature similar to the bottom surfaces 814, 824 of the first and second conductive elements 810, 820). The first pole 834 may be disposed within the opening of the first conductive element 810, and the third pole 838 may be disposed within the opening of the second conductive element 820. The first pole 834 may have a cross-sectional shape that is substantially similar to the shape of the first conductive element 810 (e.g., a cross-sectional shape shaped like a rounded square), and the third pole 838 may have a cross-sectional shape that is substantially similar to the shape of the second conductive element 820 (e.g., a cross-sectional shape shaped like a rounded square).

[0167] Furthermore, in the illustrated example, the first pole surface 844 may extend beyond the bottom surface 814 of the first conductive element 810, and the third pole surface 848 may extend beyond the bottom surface 824 of the second conductive element 820. Specifically, the first pole surface 844 and the bottom surface 814 of the first conductive element 810 may not be parallel to each other, and the third pole surface 848 and the bottom surface 824 of the second conductive element 820 may not be parallel to each other. However, in some examples, the first pole 834 and / or the third pole 838 may each extend through the first and second conductive elements 810, 820 such that the first pole surface 844 and the bottom surface 814 are parallel to each other (e.g., concentrically curved), and / or such that the third pole surface 848 and the bottom surface 824 are parallel to each other (e.g., concentrically curved). Additionally, it should be recognized that in some examples, the first pole surface 844 may be substantially planar with the bottom surface 814 of the first conductive element 810, and / or the third pole surface 848 may be substantially planar with the bottom surface 824 of the second conductive element 820.

[0168] The second pole 836 and / or the fourth pole 850 can be in the shape of a hook (e.g., as shown in the figures). The second pole 836 and / or the fourth pole 850 can each enclose (e.g., as shown in the figures, e.g., at least partially) the first and second conductive elements 810, 820. For example, the second pole 836 can extend from the first pole 834 and can enclose the upper surface 812 of the first conductive element 810. For example, the second pole 836 can be sized and shaped such that the second pole surface 846 can be substantially planar with the bottom surface 814 of the first conductive element (e.g., the second pole surface 846 can be in the plane where the upper surface 812 and the bottom surface 814 meet). Similarly, the fourth pole 840 can extend from the third pole 838 and can enclose the upper surface 822 of the second conductive element 820. For example, the fourth pole 840 can be sized and shaped such that the fourth pole surface 850 can be substantially planar with the bottom surface 824 of the second conductive element 820 (e.g., the fourth pole surface 850 can be in the plane where the upper surface 822 and the bottom surface 824 meet). However, it should be recognized that in some examples, the second pole 836 and / or the fourth pole 850 can be sized and shaped such that their respective pole surfaces can be positioned differently.

[0169] Although not shown, in some examples, the ferromagnetic component 830 can be configured to be adjustable, for example, with respect to the anatomy of the subject's head (e.g., the curvature of the ferromagnetic component 830 can be adjustable). For example, the ferromagnetic component 830 can include multiple pieces, and one or more pieces of the ferromagnetic component 830 can be configured to be adjustable with respect to one or more other pieces of the ferromagnetic component 830, and / or two or more of the pieces of the ferromagnetic component 830 can be configured to be adjustable (e.g., pivotally adjustable) with respect to each other (e.g., through the use of hinges between the pieces of the ferromagnetic component 830).

[0170] The treatment coil 800 can be configured to be driven such that the treatment coil 800 can be used to treat multiple (e.g., two) target areas of a subject. For example, during a treatment or diagnostic procedure, the treatment coil 800 can be arranged such that an area that the first conductive element 810 wraps between the first pole face 844 and the second pole face 846 can be positioned above a first target area, and an area that the second conductive element 820 wraps between the third pole face 848 and the fourth pole face 850 can be positioned above a second target area of the subject. Thereafter, the treatment coil 800 can be driven by a drive circuit of the treatment system and / or the magnetic stimulation system. For example, when driven, the current can circulate in a first direction (e.g., clockwise when viewed from the bottom perspective as shown in FIG. 8B) through the first conductive element 810, and the current can circulate in an opposite second direction (e.g., counterclockwise when viewed from the bottom perspective as shown in FIG. 8B) through the second conductive element 820, or vice versa, such that the treatment coil 800 can be configured.

[0171] As a result, the treatment coil 800 can be configured to generate a magnetic field that induces two activation zones, one at each target location. The activation zones can define a semi-elliptical shape (e.g., substantially below the area where the first conductive element 810 wraps between the first pole face 844 and the second pole face 846, and substantially below the area where the second conductive element 820 wraps between the third pole face 848 and the fourth pole face 850, respectively). For example, the treatment coil 800 can also be configured to generate a magnetic field that induces two activation zones without inducing a stimulation zone in the area below the center of the body portion 843 of the ferromagnetic component 830.

[0172] Furthermore, it should be recognized that including the second and fourth poles 836, 840 of the ferromagnetic component 830 can act to produce two activation zones that are more localized and separated than the simulation zones that would be produced by a similar treatment coil that does not include the second and fourth poles 836, 840 of the ferromagnetic component 830. Thus, the second and fourth poles 836, 840 act to further enhance the two activation zones generated by the treatment coil 800. That is, the second and fourth poles 836, 840 can strengthen or further clarify the two activation zones, where, for example, the larger and / or thicker the second and fourth poles 836, 840, the more the two activation zones are clarified (e.g., the larger and / or thicker second and fourth poles 836, 840 assist in generating a stronger gradient with respect to the electric field induced by the magnetic field generated by the treatment coil 800). Additionally, the two activation zones generated by the treatment coil 800 can be mirror images of each other.

[0173] As shown, the treatment coil 800 can be configured to generate a magnetic field including an electric field within two activation zones that are parallel to each other. However, in some examples, it should be recognized that the treatment coil 800 can be configured to generate a magnetic field including an electric field within two activation zones that are not parallel to each other. For example, one or more of the poles 834, 836, 838, 840 of the treatment coil 800 can be aligned such that the center of the pole is not parallel to one or more of the other poles 834, 836, 838, 840 of the treatment coil 800. For example, the first and second poles 834, 836 can be parallel to each other, but not parallel to the third and fourth poles 838, 840.

[0174] The treatment coil 800 can be configured such that when the first and second conductive elements 810, 820 are driven, the resulting activation zones encompass two independent areas within the subject's brain. The areas within the subject's brain can be correlated with different functional regions of the brain. For example, the treatment coil 800 can be used to stimulate two different areas within the subject's brain, such as a first area positioned below and proximate to the first conductive element 810, and a second area positioned below and proximate to the second conductive element 820. The currents within the two areas of the brain can move in the same or different directions (e.g., clockwise and / or counterclockwise).

[0175] The activation zone induced by the magnetic field generated by the treatment coil 800 can be a stimulation zone or a sub-stimulation zone. The stimulation zone can be at a level where the induced current caused by the pulsed magnetic field generated by the treatment coil 800 exceeds the depolarization threshold of the neurons in the brain, while the sub-stimulation zone can be at a level where the induced current is below the depolarization threshold of the neurons in the brain. Further, although two activation zones and two treatment areas are described, the treatment coil 800 can be used to generate a magnetic field that induces more or fewer activation zones for more or fewer treatment areas of the patient (e.g., depending on a particular treatment or diagnostic procedure).

[0176] The treatment coil 800 can be configured such that the conductive elements 810, 820 and the ferromagnetic component 830 support each other. For example, the treatment coil 800 can be configured such that the ferromagnetic component 530 supports the conductive elements 810, 820. One or both of the conductive elements 810, 820 and the ferromagnetic component 830 can include one or more complementary attachment members (not shown), and the one or more complementary attachment members are configured to enable attachment (e.g., releasable attachment) of the conductive elements 810, 820 to the ferromagnetic component 830. The one or more attachment members can be configured such that the conductive elements 810, 820 and the ferromagnetic component 830 are fixedly supported with respect to each other. The one or more attachment members can be configured such that the conductive elements 810, 820 and the ferromagnetic component 830 are movable (e.g., repositionable) with respect to each other.

[0177] When the conductive elements 810 and 820 are supported by (e.g., attached to) the ferromagnetic component 830, the conductive elements 810 and 820 can be electrically isolated from the ferromagnetic component 830, for example, using a dielectric. The dielectric can be air, and when the conductive elements 810 and 820 are attached to the ferromagnetic component 830, the conductive elements 810 and 820 can be spaced apart from the ferromagnetic component 830 (e.g., not in direct contact with the ferromagnetic component 830). The conductive elements 810 and 820 can be attached to the ferromagnetic component 830 using one or more attachment members made of any suitable electrically isolating (e.g., dielectric) material.

[0178] Figures 9A and 9B show an exemplary treatment coil 900, which is configured to generate a changing magnetic field within a target biological structure of a subject, such as a human subject (not shown). The target biological structure of the subject can be, for example, the brain tissue of the subject. The treatment coil 900 includes a first conductive element 910, a second conductive element 920, a third conductive element 960, a first ferromagnetic component 930, a second ferromagnetic component 970, and a third ferromagnetic component 980. The treatment coil 900 can be disposed proximate to the head of the subject, for example, for preparation for TMS treatment or during TMS treatment, as shown in FIG. 1. The combination of the conductive elements and ferromagnetic components of the treatment coil 900 can collectively be referred to as, for example, an electromagnet. It should be recognized that the treatment coil 900 can include more or fewer conductive elements and / or ferromagnetic components than shown (e.g., one or both of the ferromagnetic components 970 and 980 can be omitted). The conductive elements can be referred to as conductive windings. The first, second, and third conductive elements 910, 920, 960 can be made of any material that exhibits a suitable electrical conductivity, such as copper, for example.

[0179] The first and second conductive elements 910, 920 may be semi-elliptical in shape (e.g., have a rounded rectangular shape). Further, in some examples, the first and second conductive elements 910, 920 may have another shape, for example, may be circular in shape. In some examples, the first and second conductive elements 910, 920 together may form an eight-shaped coil or a B-shaped coil. The first conductive element 910 may define an upper surface 912, a bottom surface 914, an inner surface, and an outer surface 916. Similarly, the second conductive element 920 may define an upper surface 922, a bottom surface 924, an inner surface, and an outer surface 926. The outer surface 916 of the first conductive element 910 may define a recess 918 (e.g., a depression), a first ledge portion 919a, and a second ledge portion (not shown), where the recess 918 may extend between the first and second ledge portions of the outer surface 916. Similarly, the outer surface 926 of the second conductive element 920 may define a recess 928, a first ledge portion 929a, and a second ledge portion 929b, where the recess 928 may extend between the first ledge portion 929a and the second ledge portion 929b of the outer surface 926. Further, the treatment coil 900 may be configured such that (e.g., as shown) the first recess 918 is present adjacent to the second conductive element 920 and the second recess 928 is present along the outside of the treatment coil 900 (e.g., farther away from the first conductive element). However, it should be recognized that the first and second conductive elements 910, 920 may be positioned such that their respective recesses 918, 928 are present somewhere around the first and second poles 934, 936 of the first ferromagnetic component 930.

[0180] The third conductive element 960 can have a circular shape. Further, in some examples, the third conductive element 960 can have another shape, for example, it may be elliptical. The third conductive element 960 can define an upper surface 962, a bottom surface 964, an inner surface 966, and an outer surface 968. The third conductive element 960 can be shaped like a circular frustum. For example, the upper surface 962 can define a first perimeter, the bottom surface 964 can define a second perimeter, and the second perimeter can be larger than the first perimeter. However, it should be recognized that in some examples, the upper surface 962 and the bottom surface 964 can define the same perimeter. Further, it should be recognized that in some examples, the third conductive element 960 can include one or more bends or kinks. For example, the third conductive element 960 can be bent such that the upper surface 962 and the bottom surface 964 of the third conductive element 960 are not planar (e.g., flat). For example, the third conductive element 960 can be bent such that the upper surface 962 and the bottom surface 964 each define an acute angle (e.g., such that the third conductive element 960 has a "V" cross-sectional shape).

[0181] The first, second, and third conductive elements 910, 920, 960 can define the same number of turns (e.g., amp-turns), for example, a single turn as illustrated. However, it should be recognized that in some examples, the first conductive element 910, the second conductive element 920, and / or the third conductive element 960 can define a plurality of turns. For example, in some examples, any combination of the conductive elements 910, 920, 960 can define a different number of turns (e.g., the third conductive element 960 can define a plurality of turns while the first and second conductive elements 910, 920 define a single turn). Further, in some examples, the treatment coil 900 can include additional conductive elements and / or conductive elements that define a plurality of loops (e.g., amp-turns).

[0182] The first conductive element 910, the second conductive element 920, and / or the third conductive element 960 can be formed from a single monolithic piece of conductive material, or one or more of the first, second, and third conductive elements 910, 920, 960 can be formed by a plurality of strands of wire. In some examples, the treatment coil 900 can include a housing (not shown) that houses the conductive elements 910, 920, 960 and the ferromagnetic components 930, 970, 980.

[0183] The first ferromagnetic component 930 can be made from any material that exhibits suitable ferromagnetic properties, such as powdered ferromagnetic iron particles. The first ferromagnetic component 930 can include a main body portion 932 and a plurality of poles, such as a first pole 934 and a second pole 936 that extend, for example, from the main body portion 932. Although shown as having two poles, in some examples, the first ferromagnetic component 930 can include more or fewer than two poles. The plurality of poles (e.g., the first and second poles 934, 936) can extend outwardly from the main body portion 932 (e.g., from the bottom surface of the main body portion 932).

[0184] The main body portion 932 of the first ferromagnetic component 930 may define a protrusion 933 that extends upward from the upper surface of the main body portion 932. Although the protrusion 933 is shown, in some examples, the first ferromagnetic component 930 may not include the protrusion 933. The main body portion 932 may be curved, for example, as shown. For example, the upper surface of the main body portion 932 may define a convex surface, while the bottom surface of the main body portion may define a planar surface (e.g., a flat surface). Thus, the upper surface may be non-planar, and the bottom surface may be planar. Further, it should be recognized that in some examples, the curvature of the upper surface and / or the bottom surface of the main body portion 932 may define a curvature that is greater or less than that shown (e.g., the bottom surface may be curved). Moreover, it should be recognized that in some examples, the upper surface of the main body portion 932 may be planar (e.g., flat).

[0185] The first and second poles 934, 936 may define one or more pole faces. For example, the first pole 934 may define a first pole face 942 and a second pole face 944, and the second pole 936 may define a third pole face 946 and a fourth pole face 948. The first pole 934 may be disposed within the opening of the first conductive element 910, and the second pole 936 may be disposed within the opening of the second conductive element 920. The first pole 934 may have a cross-sectional shape that is substantially similar to the shape of the first conductive element 910 (e.g., a semi-elliptical cross-sectional shape), and the second pole 936 may have a cross-sectional shape that is substantially similar to the shape of the second conductive element 920 (e.g., a semi-elliptical cross-sectional shape).

[0186] The first pole surface 942 and the second pole surface 944 can be angularly offset from each other (e.g., not perpendicular, such as defining an obtuse angle as shown). Similarly, the third pole surface 946 and the fourth pole surface 948 can be angularly offset from each other (e.g., not perpendicular, such as defining an obtuse angle as shown). The first and second pole surfaces 942, 944 may be angled towards the third and fourth pole surfaces 946, 948. For example, the central axis of the first pole surface 942 may intersect the central axis of the third pole surface 946 (e.g., just below the center of the body portion 932), while the central axis of the second pole surface 944 may intersect the central axis of the fourth pole surface 948 (e.g., just below the center of the body portion 932).

[0187] Furthermore, in the example shown, the first and second pole surfaces 942, 944 may extend beyond the plane of the bottom surface 914 of the first conductive element 910, and the third and fourth pole surfaces 946, 948 may extend beyond the plane of the bottom surface 924 of the second conductive element 920. However, in some examples, it should be recognized that one or more of the first and / or second poles 934, 936 may define a single pole, and the single pole may be substantially planar with the bottom surfaces 914, 924 of the first or second conductive elements 910, 920, respectively.

[0188] Although not shown, in some examples, the first ferromagnetic component 930 may be configured to be adjustable, for example, with respect to the biological structure of the subject's head (e.g., the curvature of the first ferromagnetic component 930 may be adjustable). For example, the first ferromagnetic component 930 may include a plurality of pieces, and one or more pieces of the first ferromagnetic component 930 may be configured to be adjustable with respect to one or more other pieces of the first ferromagnetic component 930, and / or two or more of the pieces of the first ferromagnetic component 930 may be configured to be adjustable (e.g., pivotally adjustable) with respect to each other (e.g., through the use of a hinge between the pieces of the first ferromagnetic component 930).

[0189] The treatment coil 900 may also include second and third ferromagnetic components 970, 980. The second and third ferromagnetic components 970, 980 may be in a linear shape (e.g., having an elongated rectangular cross-sectional shape). The second and third ferromagnetic components 970, 980 may be disposed between the first pole 934 and the second pole 936 of the first ferromagnetic component 930 (and, for example, between the first conductive element 910 and the second conductive element 920). The second and third ferromagnetic components 970, 980 may be used to change the shape of the magnetic field generated by the treatment coil 900 (e.g., the magnetic field becomes lower as it goes deeper into the patient's head), for example, compared to the magnetic field generated by the treatment coil 900 without the second and third ferromagnetic components 970, 980. Further, the second and third ferromagnetic components 970, 980 may also improve the electrical shielding of the treatment coil 900, for example, compared to the magnetic field generated by the treatment coil 900 without the second and third ferromagnetic components 970, 980, and / or may reduce the surface close to the stimulation caused by the magnetic field generated by the treatment coil 900.

[0190] The third conductive element 960 can be referred to as, for example, an external conductive element or a halo conductive element. This is because the third conductive element 960 can be configured to wrap around the patient's coronal plane. Further, the first and second conductive elements 910, 920 and the ferromagnetic components 930, 970, 980 can be configured to be located above the opening of the third conductive element 960. As such, the third conductive element 960 can be considered to be external to the remainder of the treatment coil 900. For example, the central axis of each of any combination (for example, including all) of the first and second conductive elements 910, 920 and the first and second poles 934, 936 (for example, one or more of the pole surfaces 942, 944, 946, 948 of the first and second poles 934, 936) can pass through the opening of the third conductive element 960.

[0191] Furthermore, the first and second conductive elements 910, 920 may be arranged such that they are asymmetrically offset from the central axis of the third conductive element 960. For example, the first and second conductive elements 910, 920 and the ferromagnetic components 930, 970, 980 may be offset from the central axis of the third conductive element 960. That is, the treatment coil 900 may be configured such that the first conductive element 910 is closer to the third conductive element 960 than the second conductive element 920 is to the third conductive element 960. For example, the central axis of the first conductive element 910 may be closer to the third conductive element 960 than the central axis of the second conductive element 920 is to the third conductive element 960. Thus, as will be discussed in more detail herein, the third conductive element 960 may act to spread the return current and reduce the current outside the activation zone (e.g., reduce the surface proximate to the stimulation around the eyes, sinuses, etc. during a TMS procedure).

[0192] The treatment coil 900 can be configured to be driven such that the treatment coil 900 can be used to treat multiple (e.g., two) target areas of a subject. For example, during a treatment or diagnostic procedure, the treatment coil 900 can be arranged such that an area where the first conductive element 910 is close to the third conductive element 960 can be placed above the first target area of the subject. For example, the treatment coil 900 can be arranged such that an area where the outer surface 916 of the first conductive element 910 is close to the inner surface 966 of the third conductive element 960 can be placed above the first target area of the subject. Further, the treatment coil 900 can be arranged such that an area under the second and third ferromagnetic components 970, 980 can be placed above the second target area. Thereafter, the treatment coil 900 can be driven by a drive circuit of the treatment system and / or the magnetic stimulation system. For example, when driven, current circulates in one direction (e.g., clockwise when viewed from the bottom perspective as shown in FIG. 9B) through the first and third conductive elements 910, 960, while current circulates in the opposite direction (e.g., counterclockwise when viewed from the bottom perspective as shown in FIG. 9B) through the second conductive element 920, such that the treatment coil 900 can be configured.

[0193] As a result, the treatment coil 900 can be configured to generate a magnetic field that induces two activation zones, one for each of the target locations. The first activation zone can define an elongated oval shape (e.g., substantially below the area where the outer surface 916 of the first conductive element 910 is close to the inner surface 966 of the third conductive element 960). The second activation zone can define a semi-elliptical shape (e.g., substantially below the second and third ferromagnetic components 970, 980). For example, the first activation zone can define an elongated rounded rectangular shape, e.g., an elongated rounded rectangular shape stretched along the curvature defined by the curvature of the third conductive element 960. The treatment coil 900 can be configured to generate two activation zones and can be configured to do so by ensuring that the return current for both activation zones is on one side of the treatment coil 900. For example, the return currents of the conductive elements 910, 920, 960 can be positioned close to each other, while the activation zones are also positioned close to each other. For example, the treatment coil 900 can be driven such that a return current exists in an area close to and below the bottom surface 964 and / or the outer surface 968 of the third conductive element 960, as well as in an area close to and below the recess 928 of the second conductive element 920 (e.g., the return current is in both situations on one side of the treatment coil 900), while the activation areas can be close to the two target areas described above. Furthermore, it should be recognized that including the ferromagnetic components 970, 980 can act to further separate or clarify the two activation zones.

[0194] Moreover, it should be recognized that the treatment coil 900 can also be configured to generate a magnetic field that induces two activation zones without inducing a stimulation zone in the area between the first activation zone and the second activation zone. Further, the treatment coil 900 can also be configured not to induce a stimulation zone in the area below the bottom surface 964 and / or the outer surface 968 of the third conductive element 960. That is, the treatment coil 900 induces a plurality of activation zones in and / or below the opening defined by the third conductive element 960, but can be configured not to induce a stimulation zone outside the area below the opening of the third conductive element 960.

[0195] Furthermore, due in part to the offsets of the first and second conductive elements 910, 920 and the ferromagnetic components 930, 970, 980 from the central axis of the third conductive element 960, it should be recognized that the third conductive element 960 can act to spread the return current and reduce the current outside the activation zone (e.g., during a TMS procedure, reduce the surface close to the stimulation around, for example, the eyes, sinuses, etc.). For example, the combination of the first and second conductive elements 910, 920 and the ferromagnetic components 930, 970, 980 can be configured to be tilted towards the third conductive element 960 to generate a first activation zone (e.g., where the current is traveling in the same direction), and away from the third conductive element 960 on the opposite side (e.g., where the current is traveling in the opposite direction, and thus, for example, where the currents do not cross each other).

[0196] The treatment coil 900 can be used in various treatment and diagnostic procedures. For example, the treatment coil 900 can be used to stimulate the frontal poles above each of the patient's eyes. In such cases, it is desirable to avoid having a current flowing through the patient's eye socket or sinuses. In some examples, a third conductive element 960 can be disposed around the patient's head, such as a headband, and an area where the first conductive element 910 is proximate to the third conductive element 960 can be positioned above one of the subject's frontal poles of the eye, and an area under the second and third ferromagnetic components 970, 980 can be positioned above the other frontal pole of the subject's eye.

[0197] The treatment coil 900 can be configured such that when the conductive elements are driven, the resulting activation zone includes two independent areas within the subject's brain. The areas within the subject's brain can be correlated with different functional regions of the brain. For example, the treatment coil 900 can be used to stimulate two different areas within the subject's brain, such as a first area positioned below and proximate to the first conductive element 910, and a second area positioned below and proximate to the area where the first conductive element 910 is proximate to the third conductive element 960. The currents in the two areas of the brain can move in the same direction or different directions (e.g., clockwise and / or counterclockwise).

[0198] The activation zone induced by the magnetic field generated by the treatment coil 900 can be a stimulation zone or a sub-stimulation zone. The stimulation zone can be at a level where the induced current caused by the pulsed magnetic field generated by the treatment coil 900 exceeds the depolarization threshold of the neurons in the brain, while the sub-stimulation zone can be at a level where the induced current is below the depolarization threshold of the neurons in the brain. Further, although two activation zones and two treatment areas are described, the treatment coil 900 can be used to generate a magnetic field that induces more or fewer activation zones for more or fewer treatment areas of the patient (e.g., depending on a particular treatment or diagnostic procedure).

[0199] The treatment coil 900 can be configured such that the conductive elements 910, 920, 960 and the ferromagnetic components 930, 970, 980 support each other. For example, the treatment coil 900 can be configured such that the first ferromagnetic component 930 supports the conductive elements 910, 920, 960 and the second and third ferromagnetic components 970, 980. One or more of the conductive elements 910, 920, 960 and the ferromagnetic components 930, 970, 980 can include one or more complementary attachment members (not shown), and the one or more complementary attachment members are configured to enable the attachment (e.g., releasable attachment) of the conductive elements 910, 920, 960 and the second and third ferromagnetic components 970, 980 to the first ferromagnetic component 930. The one or more attachment members can be configured such that the conductive elements 910, 920, 960 and the ferromagnetic components 930, 970, 980 are fixedly supported with respect to each other. The one or more attachment members can be configured such that the conductive elements 910, 920, 960 and the ferromagnetic components 930, 970, 980 are movable (e.g., repositionable) with respect to each other.

[0200] When the conductive elements 910, 920, 960 and the second and third ferromagnetic components 970, 980 are supported by the first ferromagnetic component 930 (e.g., attached to the first ferromagnetic component 930), the conductive elements 910, 920, 960 can be electrically isolated from the ferromagnetic components 930, 970, 980, for example, using a dielectric. The dielectric can be air, and when the conductive elements 910, 920, 960 are attached to the ferromagnetic components 930, 970, 980, the conductive elements 910, 920, 960 can be spaced apart from the ferromagnetic components 930, 970, 980 (e.g., not in direct contact with the ferromagnetic components 930, 970, 980). The conductive elements 910, 920, 960 and the second and third ferromagnetic components 970, 980 can be attached to the first ferromagnetic component 930 using one or more attachment members made of any suitable electrically isolating (e.g., dielectric) material. Further, in some examples, combinations of the first and second conductive elements 910, 920 and the ferromagnetic components 930, 970, 980 can support each other, while it should be recognized that the third conductive element 960 can be interchanged within and outside of the treatment coil 900.

[0201] Figures 10A - 10B illustrate an exemplary treatment coil 1000, which is configured to generate a varying magnetic field within a target biological structure of a subject, such as a human subject (not shown). The target biological structure of the subject can be, for example, the brain tissue of the subject. The treatment coil 1000 includes a first conductive element 1010, a second conductive element 1020, a third conductive element 1030, a first ferromagnetic component 1040, and a second ferromagnetic component 1050. The treatment coil 1000 can be disposed proximate to the head of the subject, for example, as shown in FIG. 1, for preparation for TMS treatment or during TMS treatment. The combination of the conductive elements 1010, 1020, 1030 and the ferromagnetic components 1040, 1050 can collectively be referred to as, for example, an electromagnet. It should be recognized that the treatment coil 1000 can include more or fewer conductive elements and / or ferromagnetic components than those shown. The conductive elements can be referred to as conductive windings.

[0202] The first, second, and third conductive elements 1010, 1020, 1030 can be made of any material exhibiting suitable electrical conductivity, such as, for example, copper. The first and second conductive elements 1010, 1020 can include one or more bends. For example, the first conductive element 1010 can form a B-shaped coil, and similarly, the second conductive element 1020 can form a B-shaped coil. The first conductive element 1010 can define a bottom surface 1012, an upper surface 1014, an inner surface 1016, and an outer surface 1018. The second conductive element 1020 can define a bottom surface 1022, an upper surface 1024, an inner surface 1026, and an outer surface 1028.

[0203] The third conductive element 1030 may have a semi-elliptical shape (for example, a rounded rectangular shape). Further, in some examples, the third conductive element 1030 can have another shape, for example, it may have a circular shape. The third conductive element 1030 can define a bottom surface 1032, an upper surface 1034, an inner surface 1036, and an outer surface 1038. The second conductive element 1020 can be disposed within the opening of the third conductive element 1030. For example, the third conductive element 1030 can be configured to surround the second conductive element 1020. Further, the first, second, and / or third conductive elements may be curved. For example, the upper surfaces 1014, 1024, 1034 of the first, second, and / or third conductive elements may be concave, while the bottom surfaces 1012, 1022, 1032 of the first, second, and / or third conductive elements can be convex. However, it should be recognized that in some examples, one or more of the upper and / or bottom surfaces 1014, 1012, 1024, 1022, 1034, 1032 of the first, second, and / or third conductive elements 1010, 1020, 1030 may be planar (for example, flat).

[0204] The first, second, and / or third conductive elements 1010, 1020, 1030 may define the same number of turns (e.g., amp turns), e.g., a single turn as illustrated. However, in some examples, it should be recognized that any one or more of the first, second, and / or third conductive elements 1010, 1020, 1030 may define multiple turns. Further, any combination of the first, second, and / or third conductive elements 1010, 1020, 1030 may define a different number of turns than another one of the first, second, and / or third conductive elements 1010, 1020, 1030. Moreover, in some examples, it should be recognized that the treatment coil 1000 may include additional conductive elements and / or conductive elements that define multiple loops (e.g., amp turns). For example, the first conductive element 1010 may include one or more additional and overlapping conductive elements (e.g., the first conductive element 1010 may define multiple loops), the second conductive element 1020 may include one or more additional and overlapping conductive elements (e.g., the second conductive element 1020 may define multiple loops), and / or the third conductive element 1030 may include one or more additional and overlapping conductive elements (e.g., the third conductive element 1030 may define multiple loops). The first, second, and / or third conductive elements 1010, 1020, 1030 may be formed individually from a single monolithic piece of conductive material or one or more of the first, second, and / or third conductive elements 1010, 1020, 1030 may be formed by multiple strands of wire.

[0205] The first and second ferromagnetic components 1040, 1050 can be made from any material exhibiting suitable ferromagnetic properties, such as powdered ferromagnetic iron particles. The first ferromagnetic component 1040 can include a main body portion 1041 and a plurality of poles, which can be, for example, a first pole 1042 and a second pole 1043 extending from the main body portion 1041. Similarly, the second ferromagnetic component 1050 can include a main body portion 1051 and a plurality of poles, which can be, for example, a first pole 1052 and a second pole 1053 extending from the main body portion 1051. The first and second poles 1042, 1043 of the first ferromagnetic component 1040 can extend outwardly from the main body portion 1041 (e.g., from the bottom surface 1045 of the main body portion 1041). Similarly, the first and second poles 1052, 1053 of the second ferromagnetic component 1050 can extend outwardly from the main body portion 1051 (e.g., from the bottom surface 1055 of the main body portion 1051). Although illustrated as having two poles, in some examples, one or both of the first and second ferromagnetic components 1040, 1050 can include more or fewer than two poles. Further, in some examples, the first ferromagnetic component 1040 can include a different number of poles than the second ferromagnetic component 1050.

[0206] The main body portion 1041 of the first ferromagnetic component 1040 may define an upper surface 1044 and a bottom surface 1045. The upper surface 1044 and / or the bottom surface 1045 of the main body portion 1041 of the first ferromagnetic component 1040 may be planar (e.g., flat). However, in some examples, it should be recognized that the main body portion 1041 may be curved, as illustrated, for example, by the first ferromagnetic component 630 of the treatment coil 600. Similarly, the main body portion 1051 of the second ferromagnetic component 1050 may define an upper surface 1054 and a bottom surface 1055. The upper surface 1054 and / or the bottom surface 1055 of the main body portion 1051 of the second ferromagnetic component 1050 may be planar (e.g., flat). However, in some examples, it should be recognized that the main body portion 1051 may be curved, as illustrated, for example, by the first ferromagnetic component 630 of the treatment coil 600.

[0207] The first pole 1042 of the first ferromagnetic component 1040 may define a first pole face 1046, and the second pole 1043 may define a second pole face 1047. The first pole 1042 may be disposed within an opening (e.g., a first loop in a "B" shape) defined by the first conductive element 1010, while the second pole 1043 may be disposed within an opening (e.g., a first loop in a "B" shape) defined by the second conductive element 1020. Similarly, the first pole 1052 of the second ferromagnetic component 1050 may define a first pole face 1056, and the second pole 1053 may define a second pole face 1057. The first pole 1052 may be disposed within an opening (e.g., a second loop in a "B" shape) defined by the first conductive element 1010, while the second pole 1053 may be disposed within an opening (e.g., a second loop in a "B" shape) defined by the second conductive element 1020. Thus, the first and second pole faces 1042, 1043, 1052, 1053 of the first and second ferromagnetic components 1040, 1050 may be disposed within the openings of the first and second conductive elements 1010, 1020.

[0208] The first pole 1042 and the second pole 1043 of the first ferromagnetic component 1040 may have a cross-sectional shape shaped like a square (e.g., similar to a single loop in a "B" shape defined by the first and second conductive elements 1010, 1020). Similarly, the first pole 1052 and the second pole 1053 of the second ferromagnetic component 1050 may have a cross-sectional shape shaped like a square (e.g., similar to a single loop in a "B" shape defined by the first and second conductive elements 1010, 1020).

[0209] Furthermore, in the illustrated example, the first pole face 1046 of the first ferromagnetic component 1040 can be substantially planar with the bottom surface 1016 of the first conductive element 1010, and the second pole face 1047 can be substantially planar with the bottom surface 1026 of the second conductive element 1020. Similarly, the first pole face 1056 of the second ferromagnetic component 1050 can be substantially planar with the bottom surface 1016 of the first conductive element 1010, and the second pole face 1057 can be substantially planar with the bottom surface 1026 of the second conductive element 1020. However, in some examples, it should be recognized that one or more of the first and / or second pole faces 1046, 1047, 1056, 1057 of the first and second ferromagnetic components 1040, 1050 can extend beyond the planes of the bottom surfaces 1016, 1026 of the respective first and second conductive elements 1010, 1020.

[0210] Although not shown, in some examples, one or both of the first and / or second ferromagnetic components 1040, 1050 can be configured to be adjustable, for example, with respect to the biological structure of a subject's head (e.g., the curvature of the ferromagnetic components 1040, 1050 can be adjustable). For example, the first and / or second ferromagnetic components 1040, 1050 can include a plurality of pieces, and one or more pieces of the ferromagnetic components 1040, 1050 can be configured to be adjustable with respect to one or more other pieces of the ferromagnetic components 1040, 1050, and / or two or more of the pieces of the ferromagnetic components 1040, 1050 can be configured to be adjustable (e.g., pivotally adjustable) with respect to each other (e.g., through the use of a hinge between the pieces of the ferromagnetic components 1040, 1050).

[0211] The treatment coil 1000 can be configured to be driven so that the treatment coil 1000 can be used to treat a plurality of (e.g., two) target areas of a subject. For example, during a treatment or diagnostic procedure, an area where the first conductive element 1010 is close to the third conductive element 1030 under the bottom surface 1045 of the first ferromagnetic component 1040 can be placed above the first target area, and an area where the first conductive element 1010 is close to the third conductive element 1030 under the bottom surface 1055 of the second ferromagnetic component 1050 can be placed above the second target area of the subject, so that the treatment coil 1000 can be arranged. Thereafter, the treatment coil 1000 can be driven by a drive circuit of a treatment system and / or a magnetic stimulation system. For example, when driven, a current circulates through the first conductive element 1010 in the same first direction (e.g., counterclockwise as viewed from the lower perspective as shown in FIG. 10B), and a current circulates through the second and third conductive elements 1020, 1030 in a different second direction (e.g., clockwise as viewed from the lower perspective as shown in FIG. 10B), so that the treatment coil 1000 can be configured.

[0212] As a result, the treatment coil 1000 can be configured to generate a magnetic field that induces two activation zones, one at each of the target locations. The activation zones can define a semi-elliptical shape (e.g., in a first target area proximate to an area where the first conductive element 1010 is proximate to the third conductive element 1030 beneath the bottom surface 1045 of the first ferromagnetic component 1040, and in a second target area proximate to an area where the first conductive element 1010 is proximate to the third conductive element 1030 beneath the bottom surface 1055 of the second ferromagnetic component 1050). For example, the treatment coil 1000 can also be configured to generate a magnetic field that induces two activation zones without inducing a stimulation zone in the area between the first ferromagnetic component 1040 and the second ferromagnetic component 1050.

[0213] The two activation zones can have currents flowing in the same direction. For example, at the location where the first and third conductive elements 1010, 1030 are closest to each other, the currents flowing through the first conductive element 1010 and the third conductive element 1030 flow in the same direction, so the treatment coil 1000 can be configured to generate two activation zones with currents flowing in the same direction. In some exemplary procedures, the treatment coil 1000 can be arranged such that the first pole face 1046 of the first ferromagnetic component 1040 is disposed proximate to one eye of the patient, the first pole face 1056 is disposed proximate to the other eye of the patient, and the second pole faces 1047, 1057 of the first and second ferromagnetic components 1040, 1050 are positioned near the top of the patient's head.

[0214] In some examples, it should be recognized that one or both of the ferromagnetic components 1040, 1050 can be shifted so that the ferromagnetic components 1040, 1050 are not parallel to each other. In such cases, the treatment coil 1000 can be configured to generate two activation zones that are shifted from the illustrated embodiments of FIGS. 10A-10B. Alternatively, or additionally, in some examples, one or both of the ferromagnetic components 1040, 1050 can have their lengths extended or shortened. Finally, in some examples, one or more of the conductive elements 1010, 1020, 1030 can be planar, for example, such that the treatment coil 1000 can be configured to accommodate different head shapes.

[0215] The treatment coil 1000 can be configured such that when the first, second, and third conductive elements 1010, 1020, 1030 are driven, the resulting activation zones include two independent areas within the subject's brain. The areas within the subject's brain can be correlated with different functional regions of the brain. For example, the treatment coil 1000 can be used to stimulate two different areas within the subject's brain, such as a first area positioned below and proximate to the second pole face 1047 of the first ferromagnetic component, and a second area positioned below and proximate to the second pole face 1057 of the second ferromagnetic component. The currents in the two areas of the brain can move in the same or different directions (e.g., clockwise and / or counterclockwise).

[0216] The activation zone induced by the magnetic field generated by the treatment coil 1000 can be a stimulation zone or a sub-stimulation zone. The stimulation zone can be at a level where the induced current caused by the pulsed magnetic field generated by the treatment coil 1000 exceeds the depolarization threshold of the neurons in the brain, while the sub-stimulation zone can be at a level where the induced current is below the depolarization threshold of the neurons in the brain. Further, although two activation zones and two treatment areas have been described, the treatment coil 1000 can be used to generate a magnetic field that induces more or fewer activation zones for more or fewer treatment areas of the patient (e.g., depending on a particular treatment or diagnostic procedure).

[0217] In some examples, the treatment coil 1000 can include a housing (not shown) that houses the first, second, and third conductive windings 1010, 1020, 1030 and the first and second ferromagnetic components 1040, 1050. Also, in some examples, if the first pole of the first ferromagnetic component 1040 is configured to be disposed within the opening of one of the conductive elements, and if the first pole face of the second ferromagnetic component 1050 is configured to be disposed within the opening of the other conductive element, the first conductive element 1010 can be replaced with two semi-elliptical conductive elements. Similarly, the second conductive element 1020 can also be replaced with two semi-elliptical conductive elements.

[0218] The treatment coil 1000 can be configured such that the conductive elements 1010, 1020, 1030 and the ferromagnetic components 1040, 1050 support each other. For example, the treatment coil 1000 can be configured such that the ferromagnetic components 1040, 1050 support the conductive elements 1010, 1020, 1030. One or both of the conductive elements 1010, 1020, 1030 and the ferromagnetic components 1040, 1050 can include one or more complementary attachment members (not shown), and the one or more complementary attachment members are configured to enable attachment (e.g., releasable attachment) of the conductive elements 1010, 1020, 1030 to the ferromagnetic components 1040, 1050. The one or more attachment members can be configured such that the conductive elements 1010, 1020, 1030 and the ferromagnetic components 1040, 1050 are fixedly supported with respect to each other. The one or more attachment members can be configured such that the conductive elements 1010, 1020, 1030 and the ferromagnetic components 1040, 1050 are movable (e.g., repositionable) with respect to each other.

[0219] When the conductive elements 1010, 1020, 1030 are supported (e.g., attached) by the ferromagnetic components 1040, 1050, the conductive elements 1010, 1020, 1030 can be electrically isolated from the ferromagnetic components 1040, 1050, for example, using a dielectric. The dielectric can be air, and when the conductive elements 1010, 1020, 1030 are attached to the ferromagnetic components 1040, 1050, the conductive elements 1010, 1020, 1030 can be spaced apart from the ferromagnetic components 1040, 1050 (e.g., not in direct contact with the ferromagnetic components 1040, 1050). The conductive elements 1010, 1020, 1030 can be attached to the ferromagnetic components 1040, 1050 using one or more attachment members made of any suitable electrically isolating (e.g., dielectric) material.

[0220] Figures 11A - 11H illustrate an exemplary treatment coil 1100, which is configured to generate a varying magnetic field within a target biological structure of a subject, such as a human subject (not shown). The target biological structure of the subject can be, for example, the brain tissue of the subject. The treatment coil 1100 includes a first conductive element 1110, a second conductive element 1120, a third conductive element 1130, a first ferromagnetic component 1140, a second ferromagnetic component 1150, a third ferromagnetic component 1160, a fourth ferromagnetic component 1170, a fifth ferromagnetic component 1175, a sixth ferromagnetic component 1180, a seventh ferromagnetic component 1185, an eighth ferromagnetic component 1190a, and a ninth ferromagnetic component 1190b. The treatment coil 1100 can be disposed proximate to the head of the subject, for example, for the preparation of TMS treatment or during TMS treatment, as shown in FIG. 1. The combination of the conductive element and the ferromagnetic component can be collectively referred to as, for example, an electromagnet. The conductive element can be referred to as a conductive winding.

[0221] In FIGS. 11C to 11H, ferromagnetic components (e.g., the first, second, third, ninth, and tenth ferromagnetic components 1140, 1150, 1160, 1190a, 1190b) can be separated from the treatment coil 1100 for purposes of illustration and description. However, when the treatment coil 1100 is used, it should be recognized that the gaps between the ferromagnetic components (e.g., the first, second, third, ninth, and tenth ferromagnetic components 1140, 1150, 1160, 1190a, 1190b) themselves, and / or the gaps between the ferromagnetic components (e.g., the first, second, third, ninth, and tenth ferromagnetic components 1140, 1150, 1160, 1190a, 1190b) and the conductive element can be reduced or eliminated. Further, as described in more detail herein, the treatment coil 1100 can include more or fewer conductive elements and / or ferromagnetic components than those shown. For example, any combination of ferromagnetic components can be excluded from the treatment coil 1100 based on, for example, treatment or diagnostic procedures (e.g., target biological structures), the size and / or shape of the patient (e.g., the patient's head), and the like.

[0222] FIGS. 11A to 11B illustrate a first conductive element 1110, a second conductive element 1120, and a third conductive element 1130. The first, second, and third conductive elements 1110, 1120, 1130 can be made of any material exhibiting suitable electrical conductivity, such as, for example, copper. The first conductive element 1110 may have a semi-elliptical shape (e.g., a rounded square shape). However, in some examples, it should be recognized that the first conductive element 1110 can have another shape and, for example, may have a circular shape. The first conductive element 1110 can define an inner surface 1112, an outer surface 1114, an upper surface 1113, and a bottom surface 1115.

[0223] The second and third conductive elements 1120, 1130 may be semi-elliptical in shape (e.g., shaped like a rounded rectangle). Further, in some examples, it should be recognized that the second and third conductive elements 1120, 1130 can have another shape, for example, they may be circular in shape. The second conductive element 1120 may define an inner surface 1122, an outer surface 1124, an upper surface 1123, and a bottom surface 1125. Similarly, the third conductive element 1130 may define an inner surface 1132, an outer surface 1134, an upper surface 1133, and a bottom surface 1135. The second and / or third conductive elements 1120, 1130 may be bent downward, for example, as shown. For example, the bottom surface 1125 of the second conductive element 1120 can be concave, while the upper surface 1123 can be convex. Similarly, the bottom surface 1135 of the third conductive element 1130 can be concave, while the upper surface 1133 can be convex. However, in some examples, it should be recognized that one or more of the upper and / or bottom surfaces 1123 / 1125, 1133 / 1135 of the second and / or third conductive elements 1120, 1130 can be planar (e.g., when the second and / or third conductive elements 1120, 1130 are not bent).

[0224] The third conductive element 1130 may define a perimeter larger than that of the second conductive element 1120, and the second conductive element 1120 may define a perimeter larger than that of the first conductive element 1110. The first conductive element 1110 may be at least partially present within the opening of the second conductive element 1120, and the second conductive element 1120 may be at least partially present within the opening of the third conductive element 1130. That is, the third conductive element 1130 can surround (e.g., entirely or substantially surround) one or more of the first and / or second conductive elements 1110, 1120, and the second conductive element 1120 can surround (e.g., entirely or substantially surround) the first conductive element 1110.

[0225] The first, second, and / or third conductive elements 1110, 1120, 1130 can be formed from a single monolithic piece of conductive material, or one or more of the first, second, and / or third conductive elements 1110, 1120, 1130 can be formed from a plurality of strands of wire. Any combination of the first, second, and / or third conductive elements 1110, 1120, 1130 can define the same number of turns (e.g., ampere-turns), e.g., a single turn as illustrated. However, it should be recognized that in some examples, the second conductive element 1120 and / or the third conductive element 1130 can define a plurality of turns. For example, in some examples, the first conductive element 1100 can define a first number of turns, while one or both of the second and / or third conductive elements 1120, 1130 can define a different second number of turns.

[0226] Figures 11C to 11D illustrate a first conductive element 1110, a second conductive element 1120, a third conductive element 1130, and a first ferromagnetic component 1140. The first ferromagnetic component 1140 can be made from any material exhibiting suitable ferromagnetic properties, such as powdered ferromagnetic iron particles. The first ferromagnetic component 1140 can define an upper surface 1142, a bottom surface 1144, and eight outer surfaces (not labeled). Each of the upper surface 1142, the bottom surface 1144, and the outer surfaces can be planar. However, in some examples, it should be recognized that one or more of any combination of the upper surface 1142, the bottom surface 1144, and / or the outer surfaces may be curved or otherwise shaped. The bottom surface 1144 can be referred to as the pole face of the first ferromagnetic component 1140.

[0227] The first ferromagnetic component 1140 can be sized and shaped such that the first ferromagnetic component 1140 can be at least partially present within the opening of the first conductive element 1110. For example, the first ferromagnetic component 1140 can include a wider upper portion 1145 and a narrower bottom portion 1148. For example, the first ferromagnetic component 1140 can be shaped such that the cross-sectional shape of the first ferromagnetic component 1140 is a "T" shape. However, in some examples, it should be recognized that the first ferromagnetic component 1140 can be other shapes and can define a uniform width throughout, for example.

[0228] The upper portion 1145 may include opposite side portions 1146, 1147. The upper portion 1145 may be above the upper surface 1113 of the first conductive element 1110 and outside the opening of the first conductive element 1110, while the bottom portion 1148 may be (e.g., partially or entirely) within the opening of the first conductive element 1110. Further, the bottom surface 1144 of the first ferromagnetic component 1140 may be planar with the bottom surface 1115 of the first conductive element 1110, or may be non-planar (e.g., as shown). Finally, it should be recognized that the first ferromagnetic component 1140 may be (e.g., partially or entirely) within one or more of the openings of the second or third conductive elements 1120, 1130 (the reason being, for example, that the first conductive element 1110 may be at least partially within one or more of the openings of the second or third conductive elements 1120, 1130).

[0229] Figures 11E to 11F illustrate a first conductive element 1110, a second conductive element 1120, a third conductive element 1130, a first ferromagnetic component 1140, a second ferromagnetic component 1150, and a third ferromagnetic component 1160. The second and third ferromagnetic components 1150, 1160 can be made from any material exhibiting suitable ferromagnetic properties, such as powdered ferromagnetic iron particles. The second ferromagnetic component 1150 can define an upper surface 1152, a bottom surface 1154, a first pole surface 1156, and a second pole surface 1158. The second ferromagnetic component 1150 may be curved, for example, as illustrated. For example, the upper surface 1152 can define a convex surface, while the bottom surface 1154 can define a concave surface. Thus, the upper surface 152 can be non-planar, and the bottom surface 1154 can be non-planar. Further, in some examples, it should be recognized that the curvature of the upper surface 1152 and / or the bottom surface 1154 of the second ferromagnetic component 1150 can define a curvature greater or smaller than that illustrated. Moreover, in some examples, it should be recognized that the upper surface 1152 and / or the bottom surface 1154 of the second ferromagnetic component 1150 may be planar (e.g., flat).

[0230] The third ferromagnetic component 1160 may define an upper surface 1162, a bottom surface 1164, a first pole surface 1166, and a second pole surface 1168. The third ferromagnetic component 1160 may be curved, for example, as illustrated. For example, the upper surface 1162 may define a convex surface, while the bottom surface 1164 may define a concave surface. Thus, the upper surface 162 can be non-planar, and the bottom surface 1164 can be non-planar. Further, in some examples, it should be recognized that the curvature of the upper surface 11652 and / or the bottom surface 1164 of the third ferromagnetic component 1160 may define a curvature that is greater or less than that illustrated. Moreover, in some examples, it should be recognized that the upper surface 1162 and / or the bottom surface 1164 of the third ferromagnetic component 1160 may be planar (e.g., flat). Further, although the first and second pole surfaces 1156, 1158, 1166, 1168 of the second and third ferromagnetic components 1150, 1160 are illustrated as being planar (e.g., flat), any combination of the first and second pole surfaces 1156, 1158, 1166, 1168 of the second and third ferromagnetic components 1150, 1160 may be curved.

[0231] (For example, as shown as being lifted from the perspective view of FIG. 11E), although the second and third ferromagnetic components 1150, 1160 are shown, they can be lowered to align with the first ferromagnetic component 1140 (for example, when the treatment coil 1100 is in use). For example, the first pole surface 1156 of the second ferromagnetic component 1150 can be disposed close to the side portion 1146 of the first ferromagnetic component 1140, and the first pole surface 1166 of the third ferromagnetic component 1160 can be disposed close to the side portion 1147 of the first ferromagnetic component 1140. Thus, the upper surfaces 1152, 1162 of the second and third ferromagnetic components 1150, 1160 can align with the upper surface 1142 of the first ferromagnetic component, the bottom surfaces 1154, 1164 can align with the interface between the upper portion 1145 and the bottom portion 1148 of the first ferromagnetic component 1140, and the outer surfaces of the first, second, and third ferromagnetic components 1140, 1150, 1160 can align. Further, in some examples, when being lowered to align with the first ferromagnetic component 1140, the second pole surfaces 1158, 1168 of the second and third ferromagnetic components 1150, 1160 can be planar with the bottom surface 1135 of the third conductive element 1130.

[0232] The first, second, and third ferromagnetic components 1140, 1150, 1160 can be linearly aligned (for example, as shown). For example, the outer surfaces of the first, second, and third ferromagnetic components 1140, 1150, 1160 can be in the same plane. However, it should be recognized that in some examples, one or more of the first, second, and / or third ferromagnetic components 1140, 1150, 1160 can be aligned in a non-linear manner.

[0233] The second and third ferromagnetic components 1150, 1160 can be substantially the same size and shape. However, in some examples, the second and third ferromagnetic components 1150, 1160 can have sizes and / or shapes different from those shown. Further, in some examples, the size or shape of the second ferromagnetic component 1150 can be different from the size or shape of the third ferromagnetic component 1160 (e.g., to shift the size and / or shape of the magnetic field generated by the treatment coil 1100).

[0234] Figures 11G - 11H illustrate the first conductive element 1110, the second conductive element 1120, the third conductive element 1130, the first ferromagnetic component 1140, the second ferromagnetic component 1150, the third ferromagnetic component 1160, the fourth ferromagnetic component 1170, the fifth ferromagnetic component 1175, the sixth ferromagnetic component 1180, the seventh ferromagnetic component 1185, the eighth ferromagnetic component 1190a, and the ninth ferromagnetic component 1190b. The fourth, fifth, sixth, seventh, eighth, and ninth ferromagnetic components 1170, 1175, 1180, 1185, 1190a, 1190b can be made from any material exhibiting suitable ferromagnetic properties, such as powdered ferromagnetic iron particles, etc.

[0235] The fourth ferromagnetic component 1170 may define an outer surface 1171, an inner surface (not shown), an upper surface 1172, a bottom surface 1173, and two end surfaces 1174a, 1174b. Similarly, the sixth ferromagnetic component 1180 may define an outer surface 1181, an inner surface 1181a, an upper surface 1182, a bottom surface 1183, and two end surfaces 1184a, 1184b. The upper surfaces 1172, 1182, the bottom surfaces 1173, 1183, and the end surfaces 1174a / b, 1184a / b of the fourth and sixth ferromagnetic components 1170, 1180 may each be planar. However, in some examples, it should be recognized that one or more of the upper surfaces 1172, 1182, the bottom surfaces 1173, 1183, and the end surfaces 1174a / b, 1184a / b of the fourth and sixth ferromagnetic components 1170, 1180 may be curved or otherwise shaped.

[0236] The fourth and sixth ferromagnetic components 1170, 1180 may be curved. For example, the inner surfaces of the fourth and sixth ferromagnetic components 1170, 1180 may be concave, while the outer surfaces 1171, 1181 of the fourth and sixth ferromagnetic components 1170, 1180 may be convex. For example, the curvature of the inner and outer surfaces of the fourth and sixth ferromagnetic components 1170, 1180 may be substantially the same as the curvature of the outer surfaces of the fifth and seventh ferromagnetic elements 1175, 1185, respectively, and / or may be the same as the curvature of the third conductive element 1130. However, the curvature of the inner and outer surfaces of the fourth and sixth ferromagnetic components 1170, 1180 is not limited to that shown in FIGS. 13G - 13H.

[0237] The fourth and sixth ferromagnetic components 1170, 1180 can have substantially the same size and shape. However, in some examples, the fourth and sixth ferromagnetic components 1170, 1180 can have sizes and / or shapes different from those shown. Further, in some examples, the size or shape of the fourth ferromagnetic component 1170 can be different from the size or shape of the sixth ferromagnetic component 1180 (e.g., to shift the size and / or shape of the magnetic field generated by the treatment coil 1100).

[0238] The fifth ferromagnetic component 1175 can define an upper surface 1176, an outer surface 1177, a bottom surface (not shown), and an inner surface 1178. Similarly, the seventh ferromagnetic component 1185 can define an upper surface 1186, an outer surface 1187, a bottom surface 1188, and an inner surface 1189. The fifth and seventh ferromagnetic components 1175, 1185 can be curved (e.g., partially curved). For example, the outer surfaces 1177, 1187 of the fifth and seventh ferromagnetic components 1175, 1185 can be convex. For example, the fifth and seventh ferromagnetic components 1175, 1185 can have a semi-circular cross-sectional shape.

[0239] The inner surfaces of the fifth and seventh ferromagnetic components 1175, 1185 can be planar (e.g., flat). For example, the inner surfaces of the fifth and seventh ferromagnetic components 1175, 1185 can be parallel to the outer surface of the first ferromagnetic component 1140. The combination of the fourth and fifth ferromagnetic components 1170, 1175 can cover one or more portions (e.g., upper and outer portions) of one or more of the first, second, and / or third conductive elements 1110, 1120, 1130. Similarly, the combination of the sixth and seventh ferromagnetic components 1180, 1185 can cover one or more portions (e.g., upper and outer portions) of one or more of the first, second, and / or third conductive elements 1110, 1120, 1130.

[0240] Further, in some examples, when the second and third ferromagnetic components 1150, 1160 are aligned with the first ferromagnetic component 1140, a gap may exist between the inner surfaces of the fifth and / or seventh ferromagnetic components 1175, 1185 and the outer surfaces of the first, second, and third ferromagnetic components 1140, 1150, 1160. However, in some examples, it should be recognized that when the second and third ferromagnetic components 1150, 1160 are aligned with the first ferromagnetic component 1140, there may not be a gap between the inner surfaces of the fifth and / or seventh ferromagnetic components 1175, 1185 and the outer surfaces of the first, second, and third ferromagnetic components 1140, 1150, 1160.

[0241] The eighth ferromagnetic component 1190a may define an outer surface 1196a, an upper surface 1192a, left and right surfaces, and a bottom surface that defines a pole 1194a. Similarly, the ninth ferromagnetic component 1190b may define an outer surface 1196b, an upper surface 1192b, left and right surfaces, and a bottom surface that defines a pole 1194b. The upper surfaces of the eighth and ninth ferromagnetic components 1190a, 1190b may be of the same size and shape (e.g., the same size and shape) as the second pole faces 1158, 1168, respectively. Further, the upper surfaces of the eighth and ninth ferromagnetic components 1190a, 1190b may be parallel to the second pole faces 1158, 1168, respectively. When the treatment coil 1100 is in use, the upper surfaces of the eighth and ninth ferromagnetic components 1190a, 1190b may be disposed proximate to (and, e.g., potentially fixed to) the second pole faces 1158, 1168, respectively.

[0242] The poles 1158, 1168 of the eighth and ninth ferromagnetic components 1190a, 1190b may be angled. For example, the pole surface 1158 of the eighth ferromagnetic component 1090a may form an acute angle with the upper surface 1192a of the eighth ferromagnetic component 1090a. Similarly, the pole surface 1168 of the ninth ferromagnetic component 1090b may form an acute angle with the upper surface 1192b of the ninth ferromagnetic component 1090b. In some examples, the eighth and ninth ferromagnetic components 1190a, 1190b may be omitted from the treatment coil 1100, or may be replaced with other ferromagnetic components of any desired size and shape, such as the fourth and fifth ferromagnetic components 745a, 745b illustrated in FIG. 7C, and / or the sixth and seventh ferromagnetic components 745c, 745d illustrated in FIG. 7D.

[0243] In FIGS. 11C-11H, the ferromagnetic components (e.g., the first, second, third, ninth, and tenth ferromagnetic components 1140, 1150, 1160, 1190a, 1190b) may be separated from the treatment coil 1100 for purposes of illustration and description. However, it should be recognized that when the treatment coil 1100 is used, the gaps between the ferromagnetic components (e.g., the first, second, third, ninth, and tenth ferromagnetic components 1140, 1150, 1160, 1190a, 1190b) themselves, and / or the gaps between the ferromagnetic components (e.g., the first, second, third, ninth, and tenth ferromagnetic components 1140, 1150, 1160, 1190a, 1190b) and the conductive elements, may be reduced or eliminated.

[0244] An area where the first, second, and third conductive elements 1010, 1020, 1030 are close to the bottom surface 1154 of the second ferromagnetic component 1150 can be installed above the first target area, and an area where the first, second, and third conductive elements 1010, 1020, 1030 are close to the bottom surface 1164 of the third ferromagnetic component 1160 can be installed above the second target area of the subject (or, for example, if the ninth ferromagnetic component 1190b is included, the pole 1194b can be installed above the second target area), so that the treatment coil 1100 can be arranged. Thereafter, the treatment coil 1100 can be driven by a drive circuit of a treatment system and / or a magnetic stimulation system. For example, when driven, the treatment coil 1100 can be configured such that a current circulates in the same direction (for example, counterclockwise when viewed from the lower perspective as shown in FIG. 11H) through the first, second, and third conductive elements 1110, 1120, 1130, or vice versa.

[0245] As a result, the treatment coil 1100 can be configured to generate a magnetic field that induces two activation zones, one for each of the target locations, where each of the activation zones has an elliptical shape (for example, substantially below the area where the first, second, and third conductive elements 1010, 1020, 1030 are close to the bottom surface 1154 of the second ferromagnetic component 1150, and substantially below the area where the first, second, and third conductive elements 1010, 1020, 1030 are close to the bottom surface 1164 of the third ferromagnetic component 1160). For example, the treatment coil 1100 can also be configured to generate a magnetic field that induces two activation zones without inducing a stimulation zone in the area below the bottom surface 1144 of the first ferromagnetic component 1140.

[0246] Furthermore, including the fourth, fifth, sixth, and seventh ferromagnetic components 1170, 1175, 1180, 1185 acts to spread the return current induced by the magnetic field generated by the treatment coil 1000 (e.g., as compared to when the fourth, fifth, sixth, and seventh ferromagnetic components 1170, 1175, 1180, 1185 are not included), for example, to further clarify two activation zones generated by the magnetic field (e.g., below the first and second target areas), and prevent the two activation zones from merging into a single activation zone (e.g., a single oval or circular-shaped activation zone including the area below the bottom surface 1144 of the first ferromagnetic component 1140). That is, including the fourth, fifth, sixth, and seventh ferromagnetic components 1170, 1175, 1180, 1185 distorts the magnetic field generated by the treatment coil 1100 by spreading the return current to an area substantially below and in proximity to the fourth and sixth ferromagnetic components 1170, 1180. For example, including the fourth, fifth, sixth, and seventh ferromagnetic components 1170, 1175, 1180, 1185 pulls the return current away further from the bottom surface 1144 of the first ferromagnetic component 1040, for example, strengthens the two activation zones, and can prevent a single activation zone (e.g., one large ring) from resulting. That is, in the case where the ferromagnetic components 1170, 1175, 1180, 1185 are not included, the return current can take a shorter path, for example, the path defined by the first conductive element 1010. Therefore, the ferromagnetic components 1170, 1175, 1180, 1185 can assist in ensuring that the two activation zones do not combine (e.g., merge) into one large activation zone (e.g., a single activation zone including the area below the bottom surface 1144 of the first ferromagnetic component 1040).

[0247] It should be recognized that the treatment coil 1100 may include more or fewer conductive elements and / or ferromagnetic components than those shown. For example, any combination of ferromagnetic components may be excluded from the treatment coil 1100 based on, for example, a treatment or diagnostic procedure (e.g., a target biological structure), the size and / or shape of the patient (e.g., the patient's head), etc. In some examples, the eighth and ninth ferromagnetic components 1190a, 1190b may be omitted (e.g., due to the patient's head size and / or shape). Further, in some examples, any combination of the fourth, fifth, sixth, and / or seventh ferromagnetic components 1170, 1175, 1180, 1185 may be omitted based on, for example, a treatment or diagnostic procedure (e.g., a specific target area). For example, omission of any combination of the fourth, fifth, sixth, and / or seventh ferromagnetic components 1170, 1175, 1180, 1185 may result in changes to the separation of the stimulation zones, changes to the relative direction of the electric fields in two stimulation zones, changes to the shape of one or more of the stimulation zones, changes or movement to the return current, and / or reduction of the stimulation of the cranial nerves, etc.

[0248] The treatment coil 1100 may be configured such that when the conductive elements 1110, 1120, 1130 are driven, the resulting activation zones include two independent areas within the subject's brain. The areas within the subject's brain may be correlated with different functional regions of the brain. For example, the treatment coil 1100 may be used to stimulate two different areas within the subject's brain, such as a first area positioned below and proximate to the second pole face 1158 of the second ferromagnetic component 1150, and a second area positioned below and proximate to the second pole face 1168 of the third ferromagnetic component 1160. The currents in the two areas of the brain may move in the same direction or different directions (e.g., clockwise and / or counterclockwise).

[0249] The activation zone induced by the magnetic field generated by the treatment coil 1100 can be a stimulation zone or a sub-stimulation zone. The stimulation zone can be at a level where the induced current caused by the pulsed magnetic field generated by the treatment coil 1100 exceeds the depolarization threshold of the neurons in the brain, while the sub-stimulation zone can be at a level where the induced current is below the depolarization threshold of the neurons in the brain. Further, although two activation zones and two treatment areas have been described, the treatment coil 1100 can be used to generate a magnetic field that induces more or fewer activation zones for more or fewer treatment areas of the patient (e.g., depending on a particular treatment or diagnostic procedure).

[0250] In some examples, the treatment coil 1100 can include a housing (not shown) that houses any combination of conductive elements 1110, 1120, 1130 and ferromagnetic components 1140, 1150, 1160, 1170, 1175, 1180, 1185, 1190a, 1190b. The treatment coil 1100 can be configured such that the conductive elements 1110, 1120, 1130 and the ferromagnetic components 1140, 1150, 1160, 1170, 1175, 1180, 1185, 1190a, 1190b support each other. For example, one or more of the conductive elements 1110, 1120, 1130 and the ferromagnetic components 1140, 1150, 1160, 1170, 1175, 1180, 1185, 1190a, 1190b can include one or more complementary attachment members (not shown), and the one or more complementary attachment members are configured to enable attachment (e.g., releasable attachment) of the conductive elements 1110, 1120, 1130 to the ferromagnetic components 1140, 1150, 1160, 1170, 1175, 1180, 1185, 1190a, 1190b. The one or more attachment members can be configured such that the conductive elements 1110, 1120, 1130 and the ferromagnetic components 1140, 1150, 1160, 1170, 1175, 1180, 1185, 1190a, 1190b are fixedly supported with respect to each other. The one or more attachment members can be configured such that the conductive elements 1110, 1120, 1130 and the ferromagnetic components 1140, 1150, 1160, 1170, 1175, 1180, 1185, 1190a, 1190b are movable (e.g., repositionable) with respect to each other.

[0251] When the conductive elements 1110, 1120, and 1130 are supported by one or more of the ferromagnetic components 1140, 1150, 1160, 1170, 1175, 1180, 1185, 1190a, and 1190b (e.g., attached to one or more of the ferromagnetic components 1140, 1150, 1160, 1170, 1175, 1180, 1185, 1190a, and 1190b), the conductive elements 1110, 1120, and 1130 can be electrically isolated from the ferromagnetic components 1140, 1150, 1160, 1170, 1175, 1180, 1185, 1190a, and 1190b, for example, using a dielectric. The dielectric can be air, and when the conductive elements 1110, 1120, and 1130 are attached to the ferromagnetic components 1140, 1150, 1160, 1170, 1175, 1180, 1185, 1190a, and 1190b, the conductive elements 1110, 1120, and 1130 can be spaced apart from the ferromagnetic components 1140, 1150, 1160, 1170, 1175, 1180, 1185, 1190a, and 1190b (e.g., not in direct contact with the ferromagnetic components 1140, 1150, 1160, 1170, 1175, 1180, 1185, 1190a, and 1190b). The conductive elements 1110, 1120, and 1130 can be attached to one or more of the ferromagnetic components 1140, 1150, 1160, 1170, 1175, 1180, 1185, 1190a, and 1190b using one or more attachment members made of any suitable electrically isolating (e.g., dielectric) material.

[0252] FIG. 12 is a flowchart of an exemplary TMS treatment process 1200. The TMS treatment process 1200 can be implemented using a TMS device, such as one of the exemplary TMS devices described herein (e.g., any of the treatment coils 300, 400, 500, 600, 700, 800, 900, 1000, or 1100).

[0253] At 1202, a TMS device (e.g., a treatment coil) can be selected for use in the TMS treatment process 1200. The TMS device can be of a static configuration (e.g., by treatment coils 300, 400, 500, 600, 700, 800, 900, 1000, or 1100), or can have an adjustable and / or reconfigurable configuration. If the selected TMS device has a static configuration, the treatment process 1200 can proceed to 1208. If the selected TMS device has an adjustable and / or reconfigurable configuration, the treatment process 1200 can proceed to 1204.

[0254] At 1204, a desired treatment configuration for the TMS device can be determined. This determination can be made based on the subject's biological structure at the desired treatment location. For example, the determination can be made according to the size of the subject's head, a part of the subject's brain to be treated, and / or one or more of specific treatment or diagnostic procedures.

[0255] At 1206, the TMS device can be adjusted and / or reconfigured according to the determined treatment configuration. For example, if the TMS device 1100 is selected as the TMS device for the treatment process 1200, the treatment coil can be reconfigured by removing and / or replacing one or more ferromagnetic components (e.g., the eighth and / or ninth ferromagnetic components 1190a, 1190b). When the TMS device is adjusted and / or reconfigured according to the determined treatment configuration, the treatment process 1200 can proceed to 1208.

[0256] At 1208, the TMS device can be positioned close to the desired treatment location on the subject (e.g., close to the subject's head). For example, if the TMS device is mounted on a positioning device, the positioning device can be operated so that one or more treatment coils of the TMS device are disposed near the location of the skin on the subject's head.

[0257] At 1210, the TMS device can be operated to generate a magnetic field within a subject (e.g., within the subject's head). For example, a control circuit in electrical communication with the TMS device can be operated to deliver a pulse of current to the TMS device. At 1212, the magnetic field generated by the TMS device can be used to stimulate one or more portions of the subject's biological structure (e.g., one or more activation zones within the subject's brain). In an example, one or more portions of the subject's brain can be stimulated according to one or more stimulation cycles, each stimulation cycle including a 5-second stimulation followed by a 5-second rest period. The stimulation can be performed, for example, at an approximate frequency rate of 15 Hertz (15 Hz).

[0258] The treatment process 1200 can include using a TMS device to determine the boundaries of a subject's motor nerves. The TMS device can be configured such that localization is not required during the motor threshold location procedure. For example, the TMS device (e.g., any of treatment coils 300, 400, 500, 600, 700, 800, 900, 1000, or 1100) can be configured to generate a magnetic field in the subject's brain that stimulates a strip-shaped region of the subject's brain that encompasses the motor threshold location (e.g., in the anterior-posterior direction). The motor threshold location can be determined using the localization of the TMS device. For example, the TMS device can be moved above an area of the subject's head until an indication of positioning is observed (e.g., until the subject's thumb moves or twitches, indicating the motor threshold location). The motor threshold location can be determined, for example, using an approximate stimulation frequency rate of 1 Hz. From the motor threshold location, the TMS device can be moved to a desired treatment location above the subject. In an example, the desired treatment location can be approximately 5 centimeters (5 cm) anterior to the determined motor threshold location.

[0259] TMS devices, such as the exemplary treatment coils described herein (e.g., any of treatment coils 300, 400, 500, 600, 700, 800, 900, 1000, or 1100), can be used to treat a plurality of medical conditions or disorders, such as depression, incontinence, and weight management problems. Such treatments can be applied to a subject, for example, by using an exemplary TMS device in accordance with the exemplary TMS treatment process 1200. Exemplary TMS devices can be used to treat other medical conditions or disorders. For example, a TMS device can be used in muscle rehabilitation. A TMS device can be used in the treatment of peripheral nervous system disorders.

[0260] Exemplary TMS devices can be used in one or more of the following treatment contexts, which include major depressive disorder, epilepsy, schizophrenia, Parkinson's disease, Tourette syndrome, amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS), Alzheimer's disease, attention deficit hyperactivity disorder (ADHD), obesity, bipolar disorder and / or mania, anxiety disorders (e.g., agoraphobia, social anxiety disorder, acute stress disorder, panic disorder with and without generalized anxiety disorder), post-traumatic stress disorder (PTSD), obsessive-compulsive disorder (OCD), pain (e.g., migraine, trigeminal neuralgia), chronic pain disorders (e.g., pain resulting from diabetic neuropathy, postherpetic neuralgia), idiopathic pain disorders (e.g., fibromyalgia, local myofascial pain syndrome), post-stroke rehabilitation (neuroplasticity induction), tinnitus, stimulation of implanted neurons to promote integration, substance-related disorders (e.g., dependence, abuse, and / or withdrawal diagnoses related to alcohol, cocaine, amphetamines, caffeine, nicotine, marijuana, etc.), spinal cord injury and regeneration and / or rehabilitation, head injury, reversal of sleep deprivation, primary sleep disorders (e.g., primary insomnia, primary hypersomnia, or circadian rhythm sleep disorders), cognitive function improvement, dementia, premenstrual dysphoric disorder (PMS), drug delivery systems (e.g., changing cell membrane permeability to drugs), induction of protein synthesis (e.g., induction of transcription and translation), stuttering, aphasia, dysphagia, essential tremor, and eating disorders (e.g., bulimia nervosa, anorexia nervosa, polyphagia).

[0261] It should be appreciated that exemplary TMS devices can be used for uses other than therapeutic applications. For example, an exemplary TMS device can be used to perform a diagnosis of one or more medical conditions in a subject (e.g., in accordance with exemplary TMS treatment process 1200). For purposes of illustration, an exemplary TMS device can be used to diagnose a subject's response to a drug or other therapy and / or to quantify the effectiveness of such therapy. For example, it may be known that a pharmaceutical has an effect (e.g., a direct effect or a secondary effect) on the performance of the central nervous system. Such effects can be observed using an exemplary TMS device, for example, by providing TMS and observing one or more of the evoked potential, motor response, conduction velocity, or other responses. Observed changes in one or more such responses can be used, for example, to quantify the performance of a pharmaceutical or to determine the optimal dosing of a pharmaceutical.

[0262] An exemplary TMS device can be used to perform a diagnosis of one or more pathologies in a subject (e.g., in accordance with exemplary TMS treatment process 1200), for example, by observing neurological responses. Such pathologies can include, but are not limited to, degenerative diseases, degree of trauma, disease progression, systemic deficiencies, and congenital abnormalities. For purposes of illustration, an exemplary TMS device can be used, for example, in the diagnosis of motor dysfunction, Alzheimer's disease, Parkinson's disease, ALS, MS, diabetic neuropathy, chronic demyelinating neuropathy, acute demyelinating neuropathy, epilepsy, vitamin B12 deficiency (e.g., pernicious anemia), vitamin E deficiency, neurosarcoidosis, tinnitus, and stroke. An exemplary TMS device can be used to evaluate the effectiveness of treatment for such pathologies. For example, a TMS device can be used to assay and / or measure the effect of a pharmaceutical, such as, for example, an anticonvulsant, Alzheimer's drug, antipsychotic, analgesic, anxiolytic, hypnotic (sedative), central analgesic, ADHD drug, or anesthetic.

[0263] It should be recognized that the exemplary TMS devices described herein (e.g., any of treatment coils 300, 400, 500, 600, 700, 800, 900, 1000, or 1100) are not limited to their illustrated configurations. For example, one or more components from a first of the exemplary TMS devices may be implemented within a second of the exemplary TMS devices. In the exemplary illustrations, a fourth ferromagnetic component 745a and / or a fifth ferromagnetic component 745b may be added to treatment coil 500 and / or treatment coil 600. In another exemplary illustration, a second ferromagnetic component 680 and / or a third ferromagnetic component 690 of treatment coil 600 may be replaced with fourth, fifth, sixth, and / or seventh ferromagnetic components 1170, 1175, 1180, 1185 of treatment coil 1100. Those skilled in the art will recognize that these and other different configurations of the exemplary TMS devices may be implemented without departing from the scope and spirit of the present disclosure.

Claims

1. 1. A system for treating or diagnosing a subject, comprising: an electromagnet including a ferromagnetic component, a first conductive winding, and a second conductive winding, the ferromagnetic component comprising a main body having a top surface and a bottom surface, a first pole extending from the bottom surface of the main body, and a second pole extending from the bottom surface of the main body; a drive circuit electrically coupled to the electromagnet; a controller configured to control the drive circuit to provide current to the electromagnet to generate a pulsed magnetic field; the first conductive winding and the second conductive winding having respective openings, the first pole being disposed in the opening of the first conductive winding and the second pole being disposed in the opening of the second conductive winding.

2. The system described in claim 1, characterized in that the main body portion is curved such that the top surface of the main body portion defines a convex surface and the bottom surface of the main body portion defines a concave surface.

3. The system described in claim 1, characterized in that the first pole extends from a first end of the bottom surface and the second pole extends from a second end of the main body portion.

4. The system described in claim 3, characterized in that the ferromagnetic component further includes a third pole extending from the bottom surface of the main body portion, the third pole being between the first pole and the second pole.

5. The system described in claim 4, characterized in that the first, second, and third poles are linearly aligned.

6. The system described in claim 1, wherein the electromagnet further includes a third conductive winding having a circular shape, the third conductive winding including an opening, and the ferromagnetic component, the first conductive winding, and the second conductive winding are configured to reside above the opening in the third conductive winding.

7. The system of claim 1, characterized in that the ferromagnetic component includes a powdered magnetic material, a laminated magnetic material, or an amorphous magnetic material.

8. The system described in claim 1, characterized in that the first pole has a cross-sectional shape substantially similar to the shape of the first conductive winding, and the second pole has a cross-sectional shape substantially similar to the shape of the second conductive winding.

9. The system described in claim 1, characterized in that the first conductive winding and the second conductive winding are semi-elliptical in shape.

10. The system described in claim 1, wherein the first pole has a first pole face, the second pole has a second pole face, the first pole face is substantially planar with a bottom surface of the first conductive winding, and the second pole face is substantially planar with a bottom surface of the second conductive winding.

11. A system for treating or diagnosing a patient, comprising: an electromagnet including a ferromagnetic component, a first conductive winding, a second conductive winding, and a third conductive winding, the ferromagnetic component comprising a main body having a top surface and a bottom surface, a first pole extending from the bottom surface of the main body, and a second pole extending from the bottom surface of the main body; a drive circuit electrically coupled to the electromagnet; a controller configured to control the drive circuit to provide current to the electromagnet to generate a pulsed magnetic field; the first conductive winding and the second conductive winding having respective openings, the first pole being disposed in the opening of the first conductive winding and the second pole being disposed in the opening of the second conductive winding.

12. The system of claim 11, wherein the ferromagnetic component further includes a protrusion extending upwardly from the upper surface of the main body portion.

13. The system described in claim 11, characterized in that the first conductive winding defines an outer surface defining a first ledge portion, a second ledge portion, and a first recess extending between the first ledge portion and the second ledge portion, and the second conductive winding defines an outer surface defining a third ledge portion, a fourth ledge portion, and a second recess extending between the third ledge portion and the fourth ledge portion.

14. The system described in claim 13, characterized in that the first recess is present on a surface of the first conductive winding adjacent to the second conductive winding, and the second recess is present on a surface of the second conductive winding opposite the first conductive winding.

15. The system of claim 11, wherein the third conductive winding is circular in shape.

16. The system described in claim 11, characterized in that the third conductive winding includes an opening, and the ferromagnetic component, the first conductive winding, and the second conductive winding are configured to reside above the opening in the third conductive winding.

17. The system described in claim 16, characterized in that the electromagnet is configured such that the central axes of the ferromagnetic component, the first conductive winding, and the second conductive winding pass through the opening in the third conductive winding.

18. The system described in claim 11, characterized in that the ferromagnetic component is a first ferromagnetic component, and the electromagnet further includes a second ferromagnetic component and a third ferromagnetic component.

19. The system described in claim 18, characterized in that the second ferromagnetic component and the third ferromagnetic component are disposed between the first pole and the second pole of the first ferromagnetic component.

20. The system described in claim 18, characterized in that the second ferromagnetic component and the third ferromagnetic component are each linear in shape such that each of the second ferromagnetic component and the third ferromagnetic component has a respective cross-sectional shape of an elongated rectangle.

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