Object localization

Abstract

A method (100) for object (e.g., needle) positioning using ultrasound, the method comprising: (i) transmitting (120) a beam from elements of a single element of an array transducer of an ultrasound system (200); (ii) receiving (130) echo signals from the emitted beam at a single element of the array transducer, where at least some of the echo signals are reflected from a needle located at least partially within the patient; (iii) analyzing (140), by a processor of the ultrasound system, the received echo signal; and (iv) determining (150) a distance of the needle relative to the array transducer in the patient based on the analysis.

Description

TECHNICAL FIELD

[0001] The present disclosure relates generally to methods and systems for object (e.g., needle) localization using ultrasound. BACKGROUND

[0002] Needles and other small objects are often inserted into an animal during procedures such as biopsies. When these objects are introduced into an animal, the location of the object is essential information in order to aim or avoid parts of the body. Ultrasound is often used for needle guidance because it produces real-time images and gives good visibility of both the needle and surrounding tissue.

[0003] Needle guidance using ultrasound requires intermediate to advanced clinical skills. For example, it requires hand-eye coordination because the operator typically manipulates the needle with one hand and the ultrasound transducer with the other. A third hand would be useful to adjust the ultrasound machine settings, but would require advanced UI controls to implement. Needle guidance also requires knowledge of the vulnerability and location of tissue and organs along the planned path of the needle. Needle guidance must also account for patient movement, which can move the needle and / or internal tissue. Needle guidance also requires knowledge of the exact location of the needle tip because this is the location where material is delivered and / or removed through the needle.

[0004] While ultrasound has been successfully used to image the needle and surrounding tissue using focused and steered beams, a common problem with this design is that the needle can be difficult to visualize unless the beam is nearly perpendicular to the needle. This can again require a lot of effort, expertise, and time from the operator to find the needle using the beam, often involving adjusting the transducer until the needle is visualized, and / or manipulating the image to various angles to select a view that optimally images the needle. SUMMARY

[0005] Accordingly, there is a continuing need for ultrasound methods and systems for object (e.g., needle) localization using ultrasound. The invention is defined by the independent claims. The dependent claims define advantageous embodiments.

[0006] Accordingly, various embodiments and implementations herein relate to ultrasound methods and systems configured for object (e.g., needle) localization, where localization includes distance and / or position of the object relative to a point (e.g., an array transducer). The system transmits a beam from a single element of an array transducer and receives echo signals from the transmitted beam at the single element of the array transducer. A processor of the ultrasound system analyzes the received echo signals and determines, based on the analysis, a distance of a needle within a patient relative to the single element of the array transducer. A beam in the sense of this specification is any unfocused beam used to detect reflections from an object (e.g., a needle). In other words, the beam can be primarily spherical with a source at a single element of a transducer array. Due to constraints of the elements of the array transducer, or due to a blocking portion, the beam can not be perfectly spherical, but have a width of, for example, 30 degrees, 40 degrees, 50 degrees, 60 degrees, 70 degrees, 90 degrees, 120 degrees, 145 degrees, or 180 degrees, or any other beam angle between 30 degrees and 180 degrees. The beam width can also be larger, and smaller beam widths can be used, as long as the beam width is wide enough so as not to focus the beam on a particular feature.

[0007] The system can also be configured to repeat the steps of transmitting, receiving, analyzing, and determining for each of a plurality of elements of the array transducer; and the processor can also be configured to analyze the determined distances of the object within the patient relative to each of the plurality of elements of the array transducer to determine a position of the object within the patient relative to the array transducer.

[0008] The system can also use a user interface to report the determined distance and / or position of the needle within the patient, including superimposing the determined needle distance on an ultrasound image of the patient obtained from the determined needle position.

[0009] Generally, in one aspect, a method of object (e.g., needle) localization using ultrasound is provided. The method includes: (i) transmitting a beam from a single element of an array transducer of an ultrasound system; (ii) receiving echo signals from the transmitted beam at the single element of the array transducer, where at least some of the echo signals are reflected from a needle at least partially located within a patient; (iii) analyzing, by a processor of the ultrasound system, the received echo signals; (iv) determining, based on the analysis, a distance of the needle within the patient relative to the single element of the array transducer.

[0010] The method can also include repeating the steps of transmitting, receiving, analyzing, and determining for each of a plurality of elements of the array transducer; and an additional step of analyzing the determined distances of the object within the patient relative to each of the plurality of elements of the array transducer to determine a position of the object within the patient relative to the array transducer.

[0011] The method may also include reporting the determined distance and / or location of the needle in the patient’s body to an ultrasound operator via a user interface, including overlaying the determined needle location onto an ultrasound image of the patient obtained from the determined needle location.

[0012] According to one embodiment, the determined needle position is superimposed on an ultrasound image, including an image of the superimposed needle.

[0013] According to one embodiment, the method further includes determining that the transducer array is in an inappropriate orientation based on the determined location of the needle in the patient's body, and wherein reporting the determined location of the needle includes issuing a warning.

[0014] According to one embodiment, the position of a needle inside a patient's body is determined in 3D space.

[0015] According to one embodiment, analyzing the received echo signal includes performing a Hough transform on the received echo signal and / or performing a perspective transform on the received echo signal.

[0016] According to one embodiment, the beam is emitted from multiple elements of an array transducer in an ultrasonic system.

[0017] According to one embodiment, the method further includes adjusting the position of the needle in the patient's body based on a report of the determined location of the needle in the patient's body.

[0018] According to one embodiment, the location of a needle inside a patient's body can be determined without manipulating or focusing the emitted beam.

[0019] According to another aspect, a computer program product includes instructions that, when executed by an object positioning system, cause the system to perform any of the steps of the methods described above.

[0020] According to another aspect, there is a system for object localization during ultrasound of a patient, which is configured to perform any object localization method described herein or claimed.

[0021] It should be understood that all combinations of the foregoing concepts and the additional concepts discussed in more detail below (assuming these concepts do not contradict each other) are considered part of the inventive subject matter disclosed herein. In particular, all combinations of the claimed subject matter appearing in this disclosure are considered part of the inventive subject matter disclosed herein. It should also be understood that terms expressly adopted herein that may also appear in any disclosure incorporated by reference should conform to the meaning most consistent with the specific concepts disclosed herein.

[0022] These and other aspects of the various embodiments will be apparent from and will be set forth with reference to the embodiments described below. BRIEF DESCRIPTION OF DRAWINGS

[0023] In the drawings, like reference numerals refer to same parts throughout the various views. The drawings illustrating features and manners of implementing various embodiments should not be construed to limit other possible embodiments falling within the scope of the claims. Moreover, the drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of various embodiments.

[0024] Figure 1 is a flowchart of a method for needle localization during ultrasound, according to one embodiment.

[0025] Figure 2 is a schematic diagram of an ultrasound system, according to one embodiment.

[0026] Figure 3 is a schematic diagram of an ultrasound system transmitting beams and receiving echo signals, according to one embodiment.

[0027] Figure 4A is an enhanced image of echoes from a linear array transducer imaging a needle embedded in animal tissue, according to one embodiment.

[0028] Figure 4B is a prediction of a needle curve, according to one embodiment.

[0029] Figure 5 is a plot depicting needle depth measured using adjacent elements, according to one embodiment.

[0030] Figure 6 is a schematic diagram of an ultrasound system transmitting beams and receiving echo signals, according to one embodiment.

[0031] Figure 7A is a schematic diagram of a 45 degree needle angle, according to one embodiment.

[0032] Figure 7B is a schematic diagram of a 22 degree needle angle, according to one embodiment.

[0033] Figure 8 is a schematic diagram of a linear array creating an image(s) by translating the aperture along multiple array elements, according to one embodiment.

[0034] Figure 9 is a schematic diagram of needle localization and analysis, according to one embodiment.

[0035] Figure 10 is a schematic diagram of needle localization and analysis, according to one embodiment.

[0036] Figure 11A is a linear array image of tissue with two needles inserted, according to one embodiment.

[0037] Figure 11B is an ultrasound image of tissue including an inserted needle according to one embodiment. Figure 11A is a diverging linear array image of the same tissue and two inserted needles.

[0038] Figure 12A is an ultrasound image of tissue including an inserted needle according to one embodiment.

[0039] Figure 12B is an ultrasound image of tissue including an inserted needle according to one embodiment.

[0040] Figure 12C is an ultrasound image of tissue including an inserted needle according to one embodiment.

[0041] Figure 12D is an ultrasound image of tissue including an inserted needle according to one embodiment. DETAILED DESCRIPTION

[0042] The present disclosure describes various embodiments of ultrasound systems and methods configured to perform needle localization. More generally, Applicant has recognized and appreciated that it would be beneficial to provide improved ultrasound methods and systems for localizing needles or other small objects during surgery. Accordingly, the ultrasound system transmits a beam from a single element of an array transducer and receives echo signals from the transmitted beam at the single element of the array transducer. A processor of the ultrasound system analyzes the received echo signals and determines a distance of a needle within a patient relative to the single element of the array transducer based on the analysis. The system can then report the determined location of the needle within the patient using a user interface, including superimposing the determined needle location on an ultrasound image of the patient obtained from the determined needle location.

[0043] According to one embodiment, in some non-limiting embodiments, the systems and methods described or otherwise envisioned herein can be implemented as elements of a commercial product for ultrasound imaging or analysis, such as Philips Blue Phantom® ), or a commercial product for patient analysis or monitoring, such as Philips Patient Flow Capacity Suite (PFCS), or any suitable system.

[0044] According to one embodiment, the systems and methods described or otherwise envisioned herein enable needle path localization over a wide range of needle / beam angles and enable proper visualization of the needle path regardless of where the needle is inserted (i.e., left or right). The needle path is retrained despite small movements of the transducer or patient. Additionally, the systems and methods described or otherwise envisioned herein are 100 times faster than conventional techniques, which allows the main image of the body to run at full frame rate while tracking the needle path in real time. The systems and methods described or otherwise envisioned herein neither require focusing nor steering of the ultrasound beam, which provides a simpler and more robust solution to the problems currently faced by ultrasound localization. In other words, unfocused beams can be emitted. The beam angle can be, for example, 30 degrees, 40 degrees, 50 degrees, 60 degrees, or 70 degrees, or any other beam angle between 30 degrees and 70 degrees. Nonetheless, wider and narrower beam angles can also be used without departing from the present invention, as long as the beam angle is wide enough to not focus the image. The resulting beam will not be well focused on fine tissue that can scatter the beam (e.g., Rayleigh scattering or Mie scattering), while the inserted object (e.g., needle) will form a large “specular reflection,” allowing it to stand out more than the fine tissue, thereby enabling its identification and processing according to the present invention.

[0045] According to one embodiment, the systems and methods described or otherwise envisioned herein use diverging (e.g., in a spherical manner originating from a single element as a source) beams and avoid traditional point-focused transmit and receive beam shaping. According to one embodiment, a single element transmits a diverging beam and the same element of the array records the echoes. These echoes are then analyzed based on Snell’s law, which states that for flat or straight objects, the angle of incidence is equal to the angle of reflection. Geometric calculations locate the needle entry point relative to the end of the transducer array and the needle angle relative to the array plane. Thus, the system is able to localize the needle over a wide range of angles and points without the limitations inherent in the prior art. For example, the needle can be localized with as few as a single transmit event and without the need to steer or focus the ultrasound beam.

[0046] Reference is made to Figure 1 In one embodiment, which is a flowchart of a method 100 of needle localization using an ultrasound system. The method described in conjunction with the figures is provided by way of example only and should be understood as not limiting the scope of the present disclosure. The ultrasound system can be any system described or otherwise envisioned herein. The ultrasound system can be a single system or multiple different systems.

[0047] At step 110 of the method, an ultrasound system 200 is provided. Reference is made to FIG. 1, which illustrates an ultrasound system 200 according to one embodiment. The ultrasound system 200 can be any system described or otherwise envisioned herein. The ultrasound system 200 can be a single system or multiple different systems. Figure 2The illustrated embodiment of the ultrasound system 200, for example, includes one or more of a processor 220, a memory 230, a user interface 240, a communication interface 250, and a storage 260 interconnected via one or more system buses 212. It will be appreciated that Figure 2 Aspects are constructed in some respects and the actual organization of the components of the system 200 can be different and more complex than illustrated. Additionally, the ultrasound system 200 can be any system described or otherwise envisioned herein. Other elements and components of the ultrasound system 200 are disclosed and / or envisioned elsewhere herein.

[0048] According to one embodiment, the ultrasound systems and methods described or otherwise envisioned herein are used to locate and / or visualize a needle or other small object inserted at least partially into an animal, such as a human. For example, the ultrasound systems and methods can be used to locate placement of a needle used during a procedure, such as a biopsy, medical placement / insertion, and / or any other procedure or utilization and help guide the needle.

[0049] At step 120 of the method, a transducer of the ultrasound system transmits a beam while the needle is at least partially inserted. According to one embodiment, the beam is transmitted from an element of a single element of an array transducer of the ultrasound system. The beam can be generated and transmitted according to any method for generating and transmitting a beam from an ultrasound transducer.

[0050] According to one embodiment, an operator manipulates the transducer probe during beam transmission. The operator of the transducer and ultrasound can be the same user who manipulates the needle within the patient, or can be another individual. The user can be any user who can or is authorized to perform ultrasound, such as an ultrasound physician, nurse, physician, emergency medical technician, caregiver, or any other individual. According to one embodiment, the ultrasound device or system is a fixed device, a portable device, or a handheld device. Many other ultrasound devices and systems are possible.

[0051] According to one embodiment, a plurality of ultrasound images of any portion of a subject are obtained. The ultrasound image data can be obtained using any ultrasound device or system, which can be any device or system adapted to obtain or otherwise receive ultrasound image data of a patient. The ultrasound image data can be obtained as 2D or 3D data. The ultrasound image data can be obtained as video data. One or more parameters of the ultrasound device can be set, adjusted, preprogrammed, or otherwise determined by a healthcare professional. The ultrasound device or system includes an ultrasound transducer probe configured to obtain ultrasound images.

[0052] According to one embodiment, the ultrasound system can include patient data about a subject on which a procedure will be performed and ultrasound localization. The patient data can be any information about the patient that the ultrasound system can or can be used to analyze as described herein or otherwise envisioned. According to one embodiment, the patient data includes one or more of demographic information about the patient, the patient's medical history, the patient's diagnosis, and the reason for performing the ultrasound. For example, the demographic information can include information about the patient such as name, age, body mass index (BMI), and any other demographic information. The patient's medical history can be any historical admission or discharge information, historical treatment information, historical diagnosis information, historical examination or imaging information, and / or any other information. The patient's diagnosis can be any information about the patient's medical diagnosis, historical and / or current. The reason for performing the ultrasound can be any purpose, reason, need, or other impetus for the examination.

[0053] The patient data is received from one or more different sources. According to one embodiment, the patient data is received, retrieved, or otherwise obtained from an electronic medical record (EMR) database or system. The EMR database or system can be local or remote. The EMR database or system can be a component of the ultrasound system, or can be in local and / or remote communication with the ultrasound system. The received patient data can be used immediately, or can be stored in a local or remote storage device for further steps of the method.

[0054] The needle or other small object can be any object for a procedure that requires localization. For example, the needle or other small object can be a tool for delivering something such as a medication or treatment to the body and / or retrieving something such as a sample from the body. The needle or other small object can be a straight object, or can be a curved object, among other possible shapes and sizes.

[0055] At step 130 of the method, individual elements of the array transducer of the ultrasound system receive echo signals from the transmitted beam, where at least some of the echo signals are reflected from the needle at least partially located within the patient. The echo signals can be received according to any method for receiving echo signals by a transducer of an ultrasound system.

[0056] According to one embodiment, the transmit / receive switch reduces the receive overload during the transmit pulse. Analog time gain ("TGC") can be applied to the received echo signals, and the signals can be digitized and provided to a processor for analysis. According to one embodiment, the received echo signals are not delayed or summed. This is possible according to the present invention because the same elements of the array transducer transmit and receive the reflected echo signals.

[0057] Reference Figure 3In one embodiment, which is a schematic diagram 300 of an ultrasound system that emits a beam and receives a return signal while the needle is at least partially inserted. In this diagram, a needle 310 is at least partially inserted into tissue 320 of an animal or individual. The transducer of the ultrasound system emits a beam 330 in a spherical manner (dashed line) while the needle is at least partially inserted. A linear array 340 of the ultrasound system receives a return signal 350, at least some of which is reflected from the needle 310. The beam and return pair obey Snell's law, the angle of incidence equals the angle of reflection. Thus, the return signal reflected from the needle received by the transmitting element can be analyzed to determine the distance of the needle to the individual elements of the array transducer. Thus, by performing this transmit / receive scheme from multiple different individual elements of the array transducer, the position of the needle can be determined. Note that for each element of the array transducer, the minimum distance to the object is identified in this manner.

[0058] At step 140 of the method, the processor of the ultrasound system analyzes the received return signal. According to one embodiment, the processor analyzes each channel individually, finds a pattern in the return that matches the model, and selects the pattern that best matches the model. According to one embodiment, when analyzing each channel individually, the system can bandpass the signal at 30% bandwidth at the center frequency of the transmit waveform. The system can apply the TGC with the same properties as for the main image. The system can use a Hilbert transform or equivalent circuit to detect the waveform.

[0059] According to one embodiment, when one or more patterns in the return that match the model are found, the system can search for peaks in the received waveform and create a new waveform with only the peaks and their time positions. When a return is received from an object such as a needle, peaks will be found in the waveform.

[0060] According to one embodiment, when the pattern that best matches the model is selected, the system utilizes the model that relates the return time position to the needle angle and uses the offset to create a Hough transform of the received data. The needle angle and offset are found by searching for their peaks in the transform.

[0061] The results of the analysis by the processor can be used immediately, or can be stored in local or remote storage for further steps of the method.

[0062] At step 150 of the method, the system determines the distance and / or position of the needle within the animal or individual relative to the array transducer based on the analysis by the processor. Note that the position of the needle within the patient is determined without steering or focusing the transmitted beam.

[0063] Reference Figure 4A and 4BIn one embodiment, it is an example of needle localization using the methods and systems described or otherwise envisioned herein. For example, with reference to Figure 4A which is an enhanced image from echoes from a linear array transducer that images a needle embedded in animal tissue. There is a long transverse curve of the needle from echoes on each element. With reference to Figure 4B which is a prediction of the curve using a model according to the methods and systems described or otherwise envisioned herein.

[0064] According to one embodiment, at optional step 152 of the method, the system determines that the transducer array is in an improper orientation based on the determined location of the needle in the patient, such as whether the needle is being inserted at an unintended end of the array. Inserting the needle in the wrong location or an unintended location on the system screen can pose a threat to patient safety. For example, a possible error is holding the array in the wrong orientation, which can surprise the user when the needle is not visible due to the error. The methods and systems described or otherwise envisioned herein detect the needle path regardless of the left / right orientation of the transducer. Since many ultrasound systems have a left / right control that determines which end of the array is displayed on the left side of the image on the screen, the system can issue a warning when the orientation does not match the needle path.

[0065] At step 160 of the method, the system provides or reports the determined location of the needle in the animal or patient to the ultrasound operator via a user interface. According to one embodiment, the reported location includes superimposing the determined needle location on an ultrasound image of the patient obtained from the determined needle location. For example, as just one non-limiting example, superimposing the determined needle location on the ultrasound image includes superimposing an image of the needle. The image can be an actual image of the needle, can be a CGI-like representation of the needle, or can be any other image used to represent the needle.

[0066] The determined distance and / or location can be provided or reported to the user via any known mechanism for providing object location information. For example, the object location information can be provided on an ultrasound exam window, in another window, or on another screen (as a visual display, such as a projector or wearable device), and via any other mechanism. The provided object location information can include any elements of the analysis, and can optionally include other information, such as patient demographic or medical information and / or any other information. As an example, the object location information can be displayed to the user via the user interface as one or more marked-up images.

[0067] According to one embodiment, a method 100 for needle localization using an ultrasound system includes determining a location of a needle within an animal or individual and providing this information to a user. Thus, according to one embodiment, at step 112 of the method, an operator or user receives a report including the location of the object, where the location of the object is determined as described above.

[0068] At step 170 of the method, the user or operator utilizes the received location information. The user or operator can utilize the received location information in a variety of ways. For example, according to one embodiment, the user or operator can determine that the needle is in the proper orientation, angle, and / or position based on the report of the location information. According to another embodiment, the user or operator can determine that the needle is in an improper orientation, angle, and / or position based on the report of the location information. Thus, the user or operator will adjust the orientation, angle, and / or position of the needle. New image data can then be obtained and a new location of the needle can be obtained. Many other ways of utilizing the reported needle location information are possible.

[0069] Many variations of the methods and systems described or otherwise envisioned herein are possible. For example, for a system that manipulates to create a needle image, the system uses a needle path to optimize its manipulation and its needle image. The needle path is very responsive and reliable, but often does not show the actual needle, its components, and actions near the tip, such as fluid egress or extraction. Using a path to control needle imaging combines the advantages of the path with the clinical need to view the needle image.

[0070] According to one embodiment, an ultrasound system can include a dedicated or 3D / 4D array that is able to more completely track a needle. Typical transducers generally have a fixed elevation aperture and focal point that produces a narrow beam in a plane orthogonal to the imaging plane. However, transducers such as 3D / 4D arrays are also able to visualize in the elevation plane. Thus, a needle path algorithm can be extended to include the needle in 3D space rather than just 2D space. Conventional focused imaging algorithms can not be able to visualize the needle in 3D due to the same perpendicular issues discussed herein in 2D. However, the methods and systems described or otherwise envisioned herein address this in 3D and thus are able to give better needle path visualization compared to conventional designs.

[0071] According to one embodiment, the ultrasound system utilizes a Hough transform to extract the needle path from the received data. Alternatives to the Hough transform are also possible. In some embodiments, the Hough transform can take a long time to compute its solution because the transform finds any pattern in the data that matches the model and searches all combinations. Ultrasound images are asymmetric. Echoes are not created in the lateral dimension, but only in the axial dimension. While it is easy to image a needle oriented in the lateral dimension, it is extremely difficult to image the same needle oriented in the axial dimension. Adjacent element information can be used as an alternative to the Hough transform and can be faster and more accurate than the Hough transform method. Reference is made to Figure 5 In one embodiment, it is a plot depicting the needle depth measured using adjacent elements.

[0072] According to one embodiment, the ultrasound system creates an image from the needle path information. Both the needle path and the needle image can be important information for the clinician. One approach is to use the path information to manipulate the regular image. However, the system can also create an image from the needle path information. According to one embodiment, regular beamforming such as delay and sum can be applied to the element signals. Since only a single transmission can be utilized, the system can not be able to obtain the benefits of transmit beamforming. However, an image can still be created.

[0073] According to another embodiment, the system can utilize synthetic aperture beamforming. In this case, several diverging transmit beams can be used, up to the maximum number of channels in the array. Synthetic aperture techniques can be used to create a fully focused image in transmission and reception, which can be an ideal case for objects that do not move. However, even small movements can destroy the synthetic aperture image. In any case, there is flexibility in this approach, as in regular imaging, to trade off image quality and frame rate.

[0074] According to another embodiment, the system can optimize the transmit / receive options to create an image from the needle path information. While the preferred embodiment utilizes a single transmit element to locate the needle, beamformed transmissions from several elements can be included in the invention. The transmit aperture and waveforms can be varied to work with the methods and systems described or otherwise envisioned herein.

[0075] The methods and systems described or otherwise envisioned herein can be used to locate targets other than straight needles. For example, since the methods and systems utilize diverging beams and track echoes without regular beamforming focus, the technique can be used to find many variations including curved needles. The important aspect is that the shape of the target is well defined and can be modeled.

[0076] The methods and systems described or otherwise contemplated herein can be used with multiple element apertures. As described herein, the preferred embodiment utilizes a single transmit element and a single receive element. However, any group of one or more elements can be used. Thus, for example, adjacent transmit or receive elements can still work. It should be noted that a group of one or more elements are used in sequence, where each element transmits an echo and receives a reflected echo to determine the distance of an object relative to the element. The combination of distances can then be processed to determine the location of the object.

[0077] The methods and systems described or otherwise contemplated herein can be used with multiple transmits. As described herein, the preferred embodiment utilizes a single transmit event. However, multiple transmits can be used to improve performance. According to one embodiment, the signal-to-noise ratio (SNR) can be improved by repeating the transmit due to averaging of noise during reception. In addition, multiple transmit locations can provide better coverage. For example, the system can transmit at a first element, a center element, and a last element, thereby giving the system a wider field of view. Reference is made to Figure 6 In one embodiment, the center element transmit beam 610 is unable to identify the end of the needle tip (shown by the lack of a center transmit echo 620 of the end of the array). However, the right end of the array is easily able to identify / locate the end of the needle tip.

[0078] The methods and systems described or otherwise contemplated herein can be used with receive element delays. According to one embodiment, element delays can be used to steer reception toward the expected direction of the reflected echo. Reference is made to Figure 7A and Figure 7B which are representations of 45 degree ( Figure 7A ) and 22 degree ( Figure 7B ) needle angle (where ET = transmit element(s)). Receive steering can be used to reject echoes of undesired angles and enhance reception from desired angles.

[0079] Reference is again made to Figure 7A and Figure 7B According to one embodiment, the x-axis begins at the puncture origin “O” of the needle. All transducer elements in this embodiment are also placed along the x-axis. According to one embodiment, the needle path is defined by two parameters: (i) distance O2ab, which is the distance between “O” and the start of the transducer array; and (ii) theta, which is the needle angle measured from the x-axis.

[0080] According to one embodiment, there are three additional parameters that complete the model layout: (i) ER, which is the receive array element; (ii) ET, which is the transmit array element; and (iii) dist, which is the distance that the ultrasound travels from ET to ER via the Snell’s law reflection from the needle.

[0081] According to one embodiment, the model comprises the following trigonometry:

[0082] XET = ET * cos(theta), and YET = ET * sin(theta) (Equation 2)

[0083] XET = ET * cos(theta), and YET = ET * sin(theta) (Equation 2)

[0084] According to Snell's law, there is a point along the needle where the angle from that point to ER is the same as the angle from that point to ET, and the distance from XER to that point is A. Note that, simultaneously, the right triangle to that point is similar for ER and ET, which simplifies the equations.

[0085] Next, according to one embodiment:

[0086] A = (XET - XER) / (1 + YET / YER) (similar triangles) (Equation 3)

[0087] dist = sqrt(A^2 + YER^2) * (1 + YET / YER) (Equation 4)

[0088] This leads to the following function (such as via Matlab):

[0089] function dist_model = ComputeDist(ER, ET, Theta)

[0090] dist_model = (1 + ET / ER) * sqrt(ER^2 * sin(Theta)^2 + (-ER*cos(Theta) + ET*cos(Theta^2)) / (1 + ET / ER)^2);

[0091] end

[0092] For the Hough transform, the input data domain is dist / ER. The Hough accumulator domain is Theta / O2ab, and the Hough accumulator can be populated as follows: (i) using a single emitting element ET; and (ii) for each peak in the input data: for each of 50 different angles for Theta, for each of 80 values for O2ab, as follows:

[0093] Dist_model = ComputeDist(ER, ET, Theta) (Equation 5)

[0094] The proximity is found, which is:

[0095] abs(disk-dist_model) (Equation 6)

[0096] According to one embodiment, if proximity < 2, increment accumulator (Theta, 02ab), where the size of the increment is proportional to the brightness of the peak.

[0097] The methods and systems described or otherwise envisioned herein can be used with focused transmission. As described herein, the preferred embodiment utilizes a small number of transmission elements with beams to illuminate the entire needle. However, transmission focusing can be used to reduce signal from unwanted directions. Figure 6 The geometry of the sample transmission and reception is shown. According to one embodiment, the transmission beam, such as 630, can be focused away from the end of the needle, thereby increasing signal strength and avoiding unwanted tissue.

[0098] According to one embodiment, the methods and systems described or otherwise envisioned herein can be used with conventional ultrasound hardware and software. For example, the system can be used with linear and curved linear arrays that create images by translating the aperture along the array elements. For example, with reference to Figure 8 , the system can be used with a linear array to create an image(s) by translating the aperture along multiple array elements.

[0099] According to one embodiment, with reference to Figure 9 , which is a schematic diagram 900 of needle positioning and analysis. The ultrasound system transmits beams and receives echo signals when the needle 910 is at least partially inserted into tissue or other structure. The transducer of the ultrasound system transmits beams when the needle is at least partially inserted. The same elements of the linear transducer array of the ultrasound system receive echo signals, at least some of which are reflected from the needle 910. According to one embodiment, line 910 represents the actual needle inserted into tissue, while line 920 represents how the ultrasound system detects the needle and how it displays or represents the needle on the ultrasound screen, as shown in Figure 9 The representation 920 of the needle is not the actual location of the needle 910, and thus the received signals must be manipulated as described or otherwise envisioned herein, such that the adjusted representation of the needle is the actual location of the needle 910.

[0100] According to one embodiment, using the cadence of the linear array, the number of transmitting and receiving elements is set to one (1). Thus, each element will be used once per imaging frame. It will transmit and receive on its single element and produce one image line for the displayed image. For linear arrays, the system knows to form a complete image from the lines provided from the acquisition system.

[0101] According to one embodiment, the methods described or otherwise envisioned herein include embodiments in which needle visualization can be implemented on any ultrasound machine that supports linear arrays. Thus, the system can include software that implements the methods described or otherwise envisioned herein without requiring new equipment or equipment modification.

[0102] As Figure 9 shown, echoes from the needle 910 at angle alpha will appear on the screen at angle theta. The system displays the echoes as if they are directly in front of the transducer elements, but the echoes typically come in at an angle. Thus, the perceived location of the needle 920 or the view image provided by the system must be converted to the actual location of the needle 910. The methods described or otherwise envisioned herein make this conversion and identify which lines come from the needle and not objects that are not valid needles. For example, the perceived location of the needle 920 is converted to the actual location of the needle 910 with the following equations:

[0103] B / A = tan(theta) = sin(alpha) (Equation 7)

[0104] alpha = arcsin(B / A) (Equation 8)

[0105] According to one embodiment, needle visualization preferentially shows an image of the needle, rather than just its coordinates. Referring to Figure 10 , the length and thickness of the needle 1050 are distorted in the diverging beam image. This shows proximal echoes 1010 from the tip of the needle and distal echoes 1020 from the back of the needle. A different echo pattern of the needle is generated and a diverging beam image 1030, rather than the expected perceived location of the needle 1040 (relative to the actual location 1050) shown. Similar behavior can occur in photographs. For example, an image of a building taken looking up from the bottom of the building will show distortions of the building based on the perspective of the camera. A perspective transform can correct the distortions. Figure 9

[0106] Thus, according to one embodiment, the received echoes are processed with a perspective transform to correct the diverging beam image. This directly utilizes the diverging image and corrects it to generate a correct image of the needle.

[0107] Referring to Figure 11A and Figure 11B , which are ultrasound images of tissue including an inserted needle without the needle visualization processing. Figure 11A is a normal linear array image of tissue with two needles inserted. Figure 11B ​is the same organization and two inserted needle's diverging linear array image. According to one embodiment, image processing is required to suppress the non-needle part of the image so that the needle image stands out and can be properly utilized. Many needle visualization techniques work by steering the focused beam perpendicular to the needle. In Figure 11A the image is steered down and it is difficult to see the needle. Figure 11B the diverging image in finds the needle at all angles simultaneously. While Figure 11B the diverging image in suppresses non-needle shapes, it still needs to locate the best candidate of the needle to display.

[0108] According to one embodiment, therefore, the diverging image is analyzed to identify the lines in the image that make up the needle. When imaging is acquired by a diverging beam, the possible attributes of the needle are as follows. Some or all of these attributes can be used for image analysis:

[0109] Very straight lines (if the needle is straight);

[0110] Thin lines (most needles will not be thick, and the thickness can be a known parameter);

[0111] The entry point is outside the array and is constrained via a limiting parameter (e.g. needle length, which can be a known parameter);

[0112] The angle of the needle will be between 0 and 45 degrees;

[0113] The needle will be brighter than non-specular echoes due to its hard and shiny surface;

[0114] The brightness will have a convex shape orthogonal to its trajectory (allowing for some exceptions);

[0115] It will have continuous axial sections that satisfy the brightness attribute, but can have other sections that do not satisfy the brightness attribute;

[0116] Sections of the needle trajectory can not satisfy these attributes, and the system can apply a boundary to this fact;

[0117] Sections that successfully satisfy these checks must lie on a thin straight line (since the needle is straight);

[0118] Sections that do not satisfy must be a small fraction of the line; and / or

[0119] The end of the needle is defined as the last (farthest from the entry point) where the criteria are not satisfied.

[0120] According to one embodiment, the technique rotates the image to an angle and then processes along a horizontal line. This processing highlights the needle attributes.

[0121] Accordingly, once the diverging image is acquired, it can be processed with a perspective transform as described herein or otherwise envisioned to correct the diverging beam image and generate the true location of the needle, which can then be displayed to a user of the ultrasound system. The perspective transform can be implemented with any perspective transform sufficient to properly locate the needle with the diverging image. The perspective transform can utilize some or all of the properties listed above.

[0122] Referring to Figure 12A-12D which is an ultrasound image of tissue including an inserted needle, wherein, Figure 12A and 12C are diverging images, and Figure 12B and 12D are processed images as described herein or otherwise envisioned. Accordingly, Figure 12A is a diverging image, and Figure 12B is the same image after a perspective transform. Similarly, Figure 12C is a diverging image, and Figure 12D is the same image after a perspective transform. In Figure 12B and Figure 12D the needle is clearly identified in the image. Figure 12A and 12B are at zero degrees, and Figure 12C and 12D are rotated to 20 degrees. In this implementation, the processed image is filtered for a needle on the horizontal line.

[0123] Accordingly, at step 150 of the method, where the system determines the location of the needle within the animal or individual relative to the array transducer based on the processor’s analysis, the determination can include a perspective transform as described herein or otherwise envisioned.

[0124] Referring to Figure 2 which is a schematic diagram of an ultrasound system 200. The system 200 can be any system described herein or otherwise envisioned, and can include any components described herein or otherwise envisioned. It should be understood that Figure 2 The organization of components of the system 200 in some aspects constitutes an abstraction, and the actual organization of components of the system 200 can be different and more complex than shown.

[0125] According to one embodiment, the system 200 includes a processor 220 capable of executing instructions stored in the memory 230 or storage 260 or otherwise processing data to, for example, perform one or more steps of the method. The processor 220 can be formed of one or more modules. The processor 220 can take any suitable form, including but not limited to a microprocessor, a microcontroller, multiple microcontrollers, a circuit, a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), a single processor, or multiple processors.

[0126] Memory 230 can take any suitable form, including non-volatile memory and / or RAM. Memory 230 can include various memories, such as LI, L2, or L3 cache or system memory. As such, memory 230 can include static random access memory (SRAM), dynamic RAM (DRAM), flash memory, read-only memory (ROM), or other similar memory devices. Memory can store an operating system, among other things. RAM is used by the processor for the temporary storage of data. According to one embodiment, the operating system can contain code which, when executed by the processor, controls the operation of one or more components of system 200. It will be readily apparent to those skilled in the art that, in embodiments in which the processor implements one or more functions described herein in hardware, the software described in other embodiments as corresponding to such functions can be omitted.

[0127] User interface 240 can include one or more devices for enabling communication with a user. The user interface can be any device or system that allows for the transmission and / or reception of information, and can include a display, a mouse, and / or a keyboard for receiving user commands. In some embodiments, user interface 240 can include a command line interface or a graphical user interface that can be presented to a remote terminal via communication interface 250. The user interface can be located with one or more other components of the system, or can be located remotely from the system and communicate via a wired and / or wireless communication network.

[0128] Communication interface 250 can include one or more devices for enabling communication with other hardware devices. For example, communication interface 250 can include a network interface card (NIC) configured to communicate according to an Ethernet protocol. Additionally, communication interface 250 can implement a TCP / IP stack for communicating according to TCP / IP protocols. Various alternative or additional hardware or configurations of communication interface 250 will be readily apparent.

[0129] Storage 260 can include one or more machine -readable storage media, such as read-only memory (ROM), random access memory (RAM), magnetic disk storage media, optical storage media, flash memory devices, or similar storage media. In various embodiments, storage 260 can store instructions for execution by processor 220 or data that is operable by processor 220. For example, storage 260 can store an operating system 261 for controlling various operations of system 200.

[0130] It will be apparent that the various information described as being stored in storage 260 can additionally or alternatively be stored in memory 230. In this regard, memory 230 can also be considered to constitute storage, and storage 260 can be considered to be memory. Various other arrangements will be apparent. Moreover, both memory 230 and storage 260 can be considered to be non-transitory machine-readable media. As used herein, the term non-transitory will be understood to exclude transitory signals, but to include all forms of storage, including volatile and non-volatile memory.

[0131] While system 200 is shown to include one of each described component, various components can be replicated in various embodiments. For example, processor 220 can include multiple microprocessors that are configured to independently execute the methods described herein or that are configured to execute steps or subroutines of the methods described herein such that the multiple processors cooperate to achieve the functionality described herein. Moreover, where one or more components of system 200 are implemented in a cloud computing system, various hardware components can belong to separate physical systems. For example, processor 220 can include a first processor in a first server and a second processor in a second server. Many other variations and configurations are possible.

[0132] According to one embodiment, the ultrasound system includes or is in communication with an electronic medical record system 270, which is an electronic medical record database from which information about a patient, including clinical information and ultrasound data, can be obtained or received. The electronic medical record database can be a local or remote database and is in direct and / or indirect communication with ultrasound system 200. Thus, according to one embodiment, the ultrasound system includes an electronic medical record database or system 270.

[0133] According to one embodiment, the system includes one or more ultrasound devices 280 capable of acquiring the desired ultrasound images or analyses. According to another embodiment, ultrasound system 200 is in wired and / or wireless communication with a local or remote ultrasound device 280 capable of acquiring the desired ultrasound images or analyses.

[0134] According to one embodiment, storage 260 of system 200 can store one or more algorithms, modules, and / or instructions to perform one or more functions or steps of the methods described or otherwise envisioned herein. For example, the system can include analysis instructions 262 and / or reporting instructions 263, among other instructions or data.

[0135] According to one embodiment, analysis instructions 262 direct the system to analyze the received echo signals. According to one embodiment, analysis instructions 262 direct the system to analyze each channel individually, find a pattern in the echo that matches the model, and select the pattern that best matches the model. According to one embodiment, when analyzing each channel individually, the system can bandpass the signal at 30% bandwidth at the center frequency of the transmit waveform. The system can apply TGCs with the same properties as for the main image. The system can use a Hilbert transform or equivalent circuit to detect the waveform. Thus, analysis instructions 262 direct the system to determine the position of the needle within the animal or individual relative to the array transducer without the need to steer or focus the transmit beam. The results of the analysis can be used immediately or can be stored in local or remote storage for further steps of the method.

[0136] According to one embodiment, reporting instructions 263 instruct the system to generate and provide information to a user via a user interface including the determined position of the needle or other small object. The position information can be provided to the user via any mechanism for displaying, visualizing, or otherwise providing information via the user interface. According to one embodiment, the information can be communicated to the user interface and / or another device by wired and / or wireless communication. For example, the system can communicate the information to a mobile phone, computer, laptop, wearable device, and / or any other device configured to allow display and / or other communication of the report. The user interface can be any device or system that allows for the communication and / or reception of information, and can include a display, mouse, and / or keyboard to receive user commands.

[0137] According to one embodiment, within the context disclosed herein, embodiments can take the form of a computer program product, downloadable from a server (e.g., via the Internet), or embodied in one or more non-transitory computer-readable media having computer readable program code embodied therein. The computer program product includes computer program code instructions that, when executed by a processor, enable the processor to perform a method as described herein. The program code can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer, or entirely on the remote computer or server. The computer readable storage medium can be a tangible device that can retain and store instructions for use by an instruction execution device. The computer readable storage medium can be, for example, but is not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any combination thereof. The computer readable program instructions described herein can be downloaded to respective computing / processing devices from a computer readable storage medium or to an external computer or external storage device via a network, for example, the Internet, a local area network, and / or a wireless network. The aspects of the present application are described herein with reference to flowcharts and / or block diagrams of methods, apparatus, systems, and computer program products according to embodiments of the application. It will be understood that each block of the flowchart and / or block diagrams, and combinations of blocks in the flowcharts and / or block diagrams, can be implemented by computer readable program instructions.

[0138] According to one embodiment, the ultrasound system is configured to process thousands or millions of data points to process and analyze received ultrasound echoes and one or more ultrasound images to determine the location of a needle or other small object, and to provide a report to a user including the location. In effect, generating this location information is a process that has been relegated to a computer, as the human mind cannot perform the analysis in the required timeframe or with the required accuracy. This requires millions or billions of calculations to generate the location information. By providing an improved ultrasound system with improved location information, this system has a tremendous positive impact on patient analysis and care compared to prior art systems.

[0139] All definitions, as defined and used herein, should be understood to control over dictionary definitions, definitions in documents incorporated by reference, and / or ordinary meanings of the defined terms.

[0140] The words "a" and "an," as used herein in the specification and in claims (if any) that follow, are to be understood as meaning "at least one" unless explicitly indicated to the contrary.

[0141] The word “and / or” as used in the specification and in claims herein, should be understood to mean “one or both of” the elements so conjoined, i.e., one conjunctive element alone can be present in some cases and two conjunctive elements can be present in other cases. Multiple elements listed with “and / or” should be construed in the same fashion, i.e., “one or more” of the elements so conjoined. Other elements can optionally be present other than the elements specifically identified by the “and / or” clause, whether related or unrelated to those elements specifically identified.

[0142] As used herein in the specification and in the claims, “or” should be understood to have the same meaning as “and / or” as defined above. For example, when separating items in a list, “or” or “and / or” shall be interpreted as being inclusive, i.e., the inclusion of at least one, but also including more than one, of a number or list of elements, and, optionally, additional unlisted items. Only terms clearly

[0143] As used herein in the specification and in the claims, the phrase “at least one,” in reference to a list of one or more elements, should be understood to mean at least one element selected from among the individual elements in the list of elements, and that at least one of each element individually listed in the list of elements can be included in the at least one. Only terms clearly indicated to the contrary, such as “only one of’ or “exactly one of,” will

[0144] It will also be understood that any method disclosed herein that includes more than one step or act can be implemented by one or more apparams that eam out the recited steps or acts in any order or combination, unless a particular order or combination is expressly indicated.

[0145] In the claims, as well as in the specification above, all transitional phrases such as “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” “holding,” and the like are to be understood to be open-ended, i.e., to mean including but not limited to.

[0146] While several inventive embodiments have been described and illustrated, various modifications are possible without departing from the scope and nature of the inventive embodiments described herein, some of which have been referred to in the discussion above. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and / or configurations will depend upon the specific application or applications for which the inventive teachings is / are used. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific inventive embodiments described herein. It is, therefore, to be understood that the foregoing embodiments are presented by way of example only and that other embodiments may be developed without departing from the scope of the inventive embodiments. Inventive embodiments lie in the novel methods, systems, materials, kits, and their combination described herein.

Claims

1. A method (100) for localizing an object at least partially within a patient's body using ultrasound, the method comprising: transmitting (120) a beam from a single element of an array transducer of an ultrasound system (200); receiving (130) echo signals from the transmitted beam at the single element of the array transducer, wherein at least some of the echo signals are reflected from the object at least partially located within the patient's body; analyzing (140) the received echo signals by a processor of the ultrasound system; and based on the analysis, determining (150) a distance of the object within the patient's body relative to the single element of the array transducer.

2. The method of claim 1, wherein repeating the steps of transmitting (120), receiving (130), analyzing (140), and determining (150) for each element of a plurality of elements of the array transducer; and wherein the method further comprises the steps of: analyzing the determined distances of the object within the patient's body relative to each element of the plurality of elements of the array transducer to determine a position of the object within the patient's body relative to the array transducer.

3. The method of claim 2, wherein, Analyzing the determined distances comprises a Hough transform of the received echo signals and / or comprises a perspective transform of the received echo signals.

4. The method of claim 2 or 3, further comprising: based on the determined position of the object within the patient's body, determining (152) that the transducer array is in an improper orientation.

5. The method of claim 5, further comprising: issuing a warning that the transducer array is in an improper orientation.

6. The method of any one of claims 2 to 5, wherein, determining the position of the object within the patient's body in 3D space.

7. The method of any one of claims 1 to 6, wherein, The distance and / or the position of the object within the patient's body is determined without steering or focusing the transmitted beam.

8. The method of any of claims 1 to 7, further comprising: reporting (160) the determined distance and / or position of the object within the patient's body to an ultrasound operator via a user interface, including superimposing the determined object position on an ultrasound image of the patient obtained from the determined object position.

9. A computer program product comprising instructions which, when executed by an object localization system, cause the system to perform the steps of the method of any of claims 1 to 8.

10. A system (200) for localizing an object at least partially within a patient's body during ultrasound of the patient, the system comprising: a transducer probe comprising an array transducer; a processor (220); and a user interface (240); the system being configured to perform the method of any of claims 1 to 8.

Images