1679results about "Magnetic variable regulation" patented technology

The present invention provides systems and methods for the evaluation of the urethra and periurethral tissues using an MRI coil adapted for insertion into the male, female or pediatric urethra. The MRI coil may be in electrical communication with an interface circuit made up of a tuning-matching circuit, a decoupling circuit and a balun circuit. The interface circuit may also be in electrical communication with a MRI machine. In certain practices, the present invention provides methods for the diagnosis and treatment of conditions involving the urethra and periurethral tissues, including disorders of the female pelvic floor, conditions of the prostate and anomalies of the pediatric pelvis.

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.

An integrated high-frequency generator system utilizing the magnetic field of the target application including a magnetic resonance magnet having an application zone and a high-frequency (microwave / terahertz) generator zone in the magnetic field of the magnetic resonance magnet; and a high-frequency (microwave / terahertz) generator disposed in the high-frequency (microwave / terahertz) generator zone and utilizing the magnet field of the magnetic resonance magnet to generate the high-frequency (microwave / terahertz) radiation. The magnetic resonance magnet may have an auxiliary magnetic field source for modifying the magnetic field profile in the high-frequency (microwave / terahertz) generator zone. The high-frequency (microwave / terahertz) generator may include an electron gun for generating an electron beam adapted to be focused by a magnetic field source having a spatially rising region, a homogenous region and a decaying region, an interaction structure for generating high-frequency (microwave / terahertz) radiation, an internal mode converter in the homogenous region for extracting the high-frequency (microwave / terahertz) radiation through a window, and a reduced collector disposed substantially in the homogenous region before the electron beam spreads in the decaying region.

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.

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.

A band stop filter is provided for a lead wire of an active implantable medical device (AIMD). The band stop filter includes a capacitor in parallel with an inductor. The parallel capacitor and inductor are placed in series with the implantable lead wire of the AIMD, wherein values of capacitance and inductance are selected such that the band stop filter is resonant at a selected frequency. The Q of the inductor may be relatively maximized and the Q of the capacitor may be relatively minimized to reduce the overall Q of the band stop filter to attenuate current flow through the implantable lead wire along a range of selected frequencies. In a preferred form, the band stop filter is integrated into a TIP and / or RING electrode for the active implantable medical device.

The present invention relates to systems and methods that provide a portal user with role-based access to components on a network via portlets within the portal. The role-based access can be sharable such that one or more users with a similar role can instantiate instances of a shared portal. Sharable configurations can be stored local to the user's portal, local to another portal and / or within a networked storage medium. The access provides a user with an entry-point to components, wherein a user can monitor and control components. The user can additionally configure the portal such that the component access is further based on the user's location. Advantages of the present invention include delineation of access and administrative functionality, the ability to combine web and application servers within a similar environment, and the ability to access (e.g., controlling, collecting and analyzing data, etc.) when the user is not utilizing the portal.

A disposable tissue removal device comprises a “tube within a tube” cutting element mounted to a handpiece. The inner cannula of the cuffing element defines an inner lumen and terminates in an inwardly beveled, razor-sharp cutting edge. The inner cannula is driven by both a rotary motor and a reciprocating motor. At the end of its stroke, the inner cannula makes contact with the cutting board to completely sever the tissue. An aspiration vacuum is applied to the inner lumen to aspirate excised tissue through the inner cannula and into a collection trap that is removably mounted to the handpiece. The rotary and reciprocating motors are hydraulically powered through a foot pedal operated hydraulic circuit. The entire biopsy device is configured to be disposable. In one embodiment, the cutting element includes a cannula hub that can be connected to a fluid source, such as a valve-controlled saline bag.