5825results about "Measurements using magnetic resonance" patented technology

A system and method for using magnetic resonance imaging to increase the accuracy of electrophysiologic procedures is disclosed. The system in its preferred embodiment provides an invasive combined electrophysiology and imaging antenna catheter which includes an RF antenna for receiving magnetic resonance signals and diagnostic electrodes for receiving electrical potentials. The combined electrophysiology and imaging antenna catheter is used in combination with a magnetic resonance imaging scanner to guide and provide visualization during electrophysiologic diagnostic or therapeutic procedures. The invention is particularly applicable to catheter ablation, e.g., ablation of atrial fibrillation. In embodiments which are useful for catheter ablation, the combined electrophysiology and imaging antenna catheter may further include an ablation tip, and such embodiment may be used as an intracardiac device to both deliver energy to selected areas of tissue and visualize the resulting ablation lesions, thereby greatly simplifying production of continuous linear lesions. The invention further includes embodiments useful for guiding electrophysiologic diagnostic and therapeutic procedures other than ablation. Imaging of ablation lesions may be further enhanced by use of MR contrast agents. The antenna utilized in the combined electrophysiology and imaging catheter for receiving MR signals is preferably of the coaxial or “loopless” type. High-resolution images from the antenna may be combined with low-resolution images from surface coils of the MR scanner to produce a composite image. The invention further provides a system for eliminating the pickup of RF energy in which intracardiac wires are detuned by filtering so that they become very inefficient antennas. An RF filtering system is provided for suppressing the MR imaging signal while not attenuating the RF ablative current. Steering means may be provided for steering the invasive catheter under MR guidance. Other ablative methods can be used such as laser, ultrasound, and low temperatures.

The present invention relates to devices and methods that enhance the accuracy of lesion excision, through severing, capturing and removal of a lesion within soft tissue. Furthermore, the present invention relates to devices and methods for the excision of breast tissue based on the internal anatomy of the breast gland. A tissue severing device generally comprises a guide having at least one lumen and a cutting tool contained within the lumen. The cutting tool is capable of extending from the lumen and forming an adjustable cutting loop. The cutting loop may be widened or narrowed and the angle between the loop extension axis and the guide axis may be varied. Optional tissue marker and tissue collector may additionally be provided. A method for excising a mass of tissue from a patient is also provided. The device and method are particularly useful for excising a lesion from a human breast, e.g., through the excision and removal of a part of a breast lobe, an entire breast lobe or a breast lobe plus surrounding adjacent tissue.

A syringe for use with a powered injector to inject a fluid into a patient that includes a length of material adapted to transmit or propagate electromagnetic energy therethrough. The length of material includes at least a first indicator positioned along the length of material. The first indicator is adapted to interact with at least a portion of the energy being propagated through the length of material in a manner that is detectable. The presence (or absence) of the first indicator provides or corresponds to information about the syringe configuration. The indicator(s) of the present invention can, for example, provide information about syringe configuration by the number and / or position thereof. A plurality or set of such syringes can be provided, with the configuration of each such syringe being represented by the presence or absence of indicator(s) of that syringe.

A voltage compensation unit reduces the effects of induced voltages upon a device having a single wire line. The single wire line has balanced characteristic impedance. The voltage compensation unit includes a tunable compensation circuit connected to the wire line. The tunable compensation circuit applies supplemental impedance to the wire line. The supplemental impedance causes the characteristic impedance of the wire line to become unbalanced, thereby reducing the effects of induced voltages caused by changing magnetic fields.

Ultrasonic waveguides having improved velocity gain are disclosed for use in ultrasonic medical devices. Specifically, the ultrasonic waveguides comprises a first material having a higher acoustic impedance and a second material having a lower acoustic impedance.

Systems and methods for performing robotic endoscopic surgical procedures, according to a surgical plan prepared on a preoperative set of three dimensional images. The system comprises a surgical robot whose coordinate system is related to that of fluoroscope images generated intraoperatively, by using a three dimensional target having radio-opaque markers, attached in a predetermined manner to the robot or to another element to which the robot is attached, such as the spinal bridge or an attachment clamp. The robot is mounted directly or indirectly on a bone of the patient, thereby nullifying movement of the bone, or a bone tracking system may be utilized. The coordinate system of the intraoperative fluoroscope images may be related to the preoperative images, by comparing anatomical features between both image sets. This system and method enables the endoscope to be directed by the robot along the exact planned path, as determined by the surgeon.