Abstract: A method and apparatus generate electrical currents and/or voltage in tissue using particles composed of liquid crystals and magnetic particles.

Abstract: A tubing assembly includes a signal generating apparatus for a catheter placement system. The tubing assembly includes a catheter and a signal generating apparatus. The catheter includes an elongate shaft having a wall surrounding a lumen. The signal generating apparatus includes at least one electromagnetic coil and at least one electrically conductive polymer that is configured to electrically connect the at least one electromagnetic coil to a monitor unit.

Abstract: The present disclosure provides methods for targeting a biomedical system. Aspects of the subject methods include determining the trajectory of a targeting device using magnetic resonance imaging (MRI) of a MRI-visible style of a trajectory guide that is compatible with the targeting device. Targeted biomedical systems may be utilized for a variety of purposes including targeted delivery of a therapeutic, holding a therapeutic device, positioning of a therapeutic device and other uses. Also provided are devices and systems that can be used in practicing the described methods including but not limited to trajectory guides and adjustable targeting systems, as well as non-transitory computer readable medium storing instructions that, when executed by a computing device, cause a computing device to perform steps of the described methods.

Abstract: Trajectory frame assemblies for image guided surgical systems have a trajectory frame with a support column that can removably secure different components such as a tracking probe and an MER driver adapter to define and/or follow a desired intrabody trajectory. The trajectory frame assemblies include fins attached to the column support and a platform optionally with an X-Y table and/or arcuate reference brackets that are attached to the trajectory frame assemblies and can hold a reference frame with fiducials.

Abstract: According to some aspects, a magnetic resonance imaging system capable of imaging a patient is provided. The magnetic resonance imaging system comprising at least one B0 magnet to produce a magnetic field to contribute to a B0 magnetic field for the magnetic resonance imaging system and a member configured to engage with a releasable securing mechanism of a radio frequency coil apparatus, the member attached to the magnetic resonance imaging system at a location so that, when the member is engaged with the releasable securing mechanism of the radio frequency coil apparatus, the radio frequency coil apparatus is secured to the magnetic resonance imaging system substantially within an imaging region of the magnetic resonance imaging system.

Abstract: A flexible coil with improved tolerance for overlapping antennas and with reduced susceptibility to the introduction of image artifacts as a result of overlapping antennas utilizes antennas with multiple conductors extending in parallel for the length of the antenna. Each conductor is connected to the other conductor at each end creating parallel conduction paths for the length of the antenna. The parallel conduction paths reduce the resistance of the antenna which, in turn, improves the quality factor of the antenna. The improved quality factor results in antennas that are less susceptible to image artifacts being induced in the antenna due to coupling from an overlapping antenna.

Abstract: The present invention relates to operating a biopsy unit. In order to provide an enhanced and facilitated way of controlling a biopsy unit, a control device (10) for controlling a biopsy unit is provided that comprises a support structure (12) with a housing (14), and a user interface unit (16) with a plurality of control elements (18). The control elements are configured to control the movement of a biopsy needle device along at least three moving direction lines. At least two of the moving direction lines are aligned to axes of a Cartesian coordinate system (20) and one moving direction line is aligned to a needle axis direction (22) of an elongated needle device of the biopsy unit, the needle axis direction being inclined to at least one of the axes of the Cartesian coordinate system. For each moving direction line, the housing is provided with a surface portion (24, 26, 28) that is aligned with a respective one of the moving direction lines.

Abstract: Embodiments include a system for providing blood flow information for a patient. The system may include at least one computer system including a touchscreen. The at least one computer system may be configured to display, on the touchscreen, a three-dimensional model representing at least a portion of an anatomical structure of the patient based on patient-specific data. The at least one computer system may also be configured to receive a first input relating to a first location on the touchscreen indicated by at least one pointing object controlled by a user, and the first location on the touchscreen may indicate a first location on the displayed three-dimensional model. The at least one computer system may be further configured to display first information on the touchscreen, and the first information may indicate a blood flow characteristic at the first location.

Abstract: A system and method for analysis of 3D deformations and regional function of a heart includes: a magnetic resonance imaging (MRI) scanner configured to acquire three tagged volume data series with mutually perpendicular tag lines of a heart; a data storage device in communication with the MRI scanner and configured to store the three tagged volume data series; and an image processing machine in communication with data storage device. The image processing machine is configured to: model an intensity distribution around each voxel of each tagged volume data series as a moving sine wave front with a local frequency and an amplitude; and determine a phase and frequency for each voxel from the local frequency and amplitude and a displacement from a quotient of a phase difference and the local frequency.

Abstract: A method of performing a percutaneous multi-probe treatment includes: acquiring a scan image of an object to be treated with multi-probe percutaneous insertions; determining a first point in a region of interest (ROI) in the scan image; determining a second point at a surface of the object in the scan image; generating a reference trajectory by connecting the first point and the second point; arranging, around the first point, a number of third points corresponding to tips of probes to be inserted into the object; generating planned insertion trajectories for the probes based on the number of probes to be inserted and the reference trajectory; and causing a monitor to display superposed on the scan image, at least one of the planned insertion trajectories. The planned insertion trajectories extend in a geometric relationship to the reference trajectory and pass through the third points and through one or more second points.

Abstract: A surgical instrument for cutting tissue includes a sleeve, a shaft slidably disposed within the sleeve and defining a longitudinal axis, and a plurality of legs coupled to the shaft and disposed about the longitudinal axis. Each leg has a blade attached to an end portion thereof and each blade defines a cutting edge. The shaft is slidable relative to the sleeve between a collapsed configuration, wherein the legs are disposed within the sleeve, and an expanded configuration, wherein the legs extend distally and radially outwardly from the sleeve. In the expanded configuration, the cutting edge of each blade is disposed in a proximally-facing orientation. Alternatively, the shaft is rotatable relative to the sleeve to rotate the legs about the longitudinal axis, thereby rotating each blade through a circular cutting path defining a different diameter. Methods of cutting tissue are also provided.

Abstract: Trajectory frame assemblies for image guided surgical systems have a trajectory frame with a support column that can removably secure different components such as a tracking probe and an MER driver adapter to define and/or follow a desired intrabody trajectory. The trajectory frame assemblies include fins attached to the column support and a platform optionally with an X-Y table and/or arcuate reference brackets that are attached to the trajectory frame assemblies and can hold a reference frame with fiducials.

Abstract: In a method and computer for planning magnetic resonance imaging of a body of an examination object that contains an implant, to be implemented by a magnetic resonance apparatus, position information of the implant is provided to the computer, the position information characterizing a position of the implant in the body of the examination object, and at least one imaging parameter for the magnetic resonance imaging is predetermined before the imaging. At least one load parameter of the implant is established in the computer on the basis of the acquired position information and the at least one predetermined imaging parameter. The magnetic resonance imaging is planned in the computer on the basis of the established load parameter of the implant.

Abstract: An RF coil has an improved structure to prevent an excessive heat from being transferred to an object, and a magnetic resonance imaging apparatus includes the same. The MRI apparatus includes an RF coil configured to receive an RF signal, wherein the RF coil may include a first cover configured to allow thermal insulation material to be injected into the inside thereof, a second cover configured to allow thermal insulation material to be injected into the inside thereof and detachably coupled to the first cover to form an inner space with the first cover, and at least one circuit board disposed in the inner space and on which a circuit element configured to receive the RF signal is mounted.

Abstract: A catheter (10) comprising a catheter tip (14) that is adapted to have deflection of an associated spring (22) detected by imaging techniques and to have that deflection be translated into an estimation of the tip (14) contact force.

Abstract: A coil pad according to one embodiment is a coil pad that is placed between a receiving coil and a subject. The receiving coil is mounted on the subject and receives a magnetic resonance signal emitted from the subject. The coil pad includes a pad opening and a vibrating portion. The pad opening is aligned with a coil opening included in the receiving coil and forms a through-hole between the coil opening and the subject. The vibrating portion vibrates with a medium that transmits vibration being filled therein.

Abstract: A system and method for producing an image using a radio frequency (RF) coil in a magnetic resonance imaging system (MRI). A static magnetic field (B0) extends across a first and second region of interest (ROI). A local radio frequency (RF) coil, shaped like a dental arch, is positioned proximate to the ROIs, the ROIs being the upper and lower jaw of a subject. The RF coil and the subject are oriented in the static magnetic field (B0) to align an axis extending through a loop of the coil with the B0 direction of the static magnetic field extending across the ROIs. A pulse sequence is then performed with the MRI system and the RF coil to acquire imaging data from the ROIs simultaneously while using a transverse component of an excitation field (B1). The image data is reconstructed to create an image of the ROIs.

Abstract: In order to configure a transmission coil of a magnetic resonance imaging (MRI) system without taking a specific measurement object into account, the transmission coil is automatically detected and identified when the transmission coil is connected to the MRI system. A phase setting of a pulse to be transmitted by the detected transmission coil is identified based on at least the identified type of the transmission coil. The transmission coil is excited with the pulse having the identified phase and amplitude.

Abstract: An MRI-guided interventional system for use with a patient and an interventional device includes a base, a trajectory guide frame, and a mounting device. The base is configured to be secured to a body of the patient. The trajectory guide frame includes a targeting cannula. The targeting cannula has an elongate guide bore extending axially therethrough, defining a trajectory axis, and being configured to guide placement of the interventional device. The trajectory guide frame is operable to move the targeting cannula relative to the base to position the trajectory axis to a desired intrabody trajectory to guide placement of the interventional device in vivo. A plurality of patient engagement structures are provided on the base and are configured to penetrate tissue of the body and to space the base apart from the tissue. The system further includes a plurality of fasteners configured to secure the base to the body.

Abstract: Intrabody MRI-compatible medical devices with a rigid stylet body with opposing distal and proximal ends with a wall enclosing at least one cavity extending therebetween. The stylet body has first and second laterally spaced apart and opposing external longitudinally extending recessed surfaces and at least one pair of transversely spaced apart apertures extending through the wall and at least one conductor having a length that extends through the cavity then exits the cavity to define at least one external loop extending between the distal end of the stylet body and the pair of transversely spaced apart apertures. First and second legs of each loop snugly abut a respective first and second recessed surface of the stylet body to thereby cooperate with the stylet body to define a substantially cylindrical shape. The at least one conductor with the at least one loop is configured to act as an MRI antenna.

Abstract: Apparatus associated with improved magnetic resonance imaging (MRI) guided needle biopsy procedures (e.g., breast needle biopsy) are described. One example apparatus includes a support structure configured to support a patient in a face-down prone position where a breast of the patient is positioned in a first free hanging pre-imaging position. The example apparatus includes an immobilization structure configured to reposition the breast into an immobilized position suitable for MRI and for medical instrument access. The immobilization structure may include a biopsy plate, a pressure plate, and MRI coils. The MRI coils are configured to be repositioned from a first position associated with the free hanging pre-imaging position to a second position associated with the immobilized position to facilitate improving the signal to noise ratio associated with signal received from the breast through the MRI coils. The biopsy plate is removable without removing either of the MRI coils.

Abstract: An MRI antenna array including a housing and a substrate, antenna elements and circuitry encapsulated by the housing. The housing, antenna elements, and substrate are flexible to allow the housing to distort in three dimensions to closely conform to contours of a patient. The antenna elements are mounted to the substrate in a manner that permits each element to maintain a desired resonance when the housing is distorted in three dimensions. The circuitry is electrically coupled with the antenna elements to maintain tuning and isolation of the elements when the housing is distorted in three dimensions. The housing, antenna elements, and substrate may be elastic to allow the housing to be worn by a plurality of different sized patients so that the housing is in close contact with the patient and conforms to contours of the patient.

Abstract: Provided are a spectroscopic method and spectroscopic device for analyzing a region. Layers or coats of materials with high dielectric constant or permittivity with very low conductivity are inserted in between radiofrequency (RF) coil or coil's conductive elements and the sample to enhance the signal to noise ratio (SNR), improve image contrast, and reduce the specific absorption rate (SAR) of magnetic resonance imaging or magnetic resonance spectroscopy instruments. The embodiments of the present invention can be used as an auxiliary device to the standard pre-constructed RF coils or incorporated with RF coil constructions for enhancing RF coil performances in both transmission and reception.

Abstract: The disclosure describes cable management systems that provide adjustable lengths of cables that connect to various electronic medical or surgical tools. The systems can reduce the lengths of loose or hanging cables and define routes that preventing cross-over, looping and/or bunching of loose lengths of long cables.

Abstract: A method and apparatus for radially compressing bodily tissue and performing medical procedures from a selected one of a plurality of circumferential positions and angles, a selected one of a plurality of different elevations and elevational angles. Some embodiments include a tissue-compression fixture having members that are configured to be moved to radially compress bodily tissue such that each of a plurality of areas of biological tissue are exposed between the plurality of members, and wherein the fixture is compatible with use in an MRI machine in operation; an actuator having a receiver for a medical-procedure probe; and a computer system operatively coupled to the actuator to move the probe. The computer receives user commands, and based on the commands, moves the actuator to a selected one of a plurality of different positions around the tissue-compression fixture and then extends the probe into the patient.

Abstract: A method and apparatus for designing and fabricating a pantomesh. The pantomesh includes a plurality of pantomesh elements each including a pairs of links connected to one another by a revolute joint at points between their ends. Each of a plurality of the pantomesh elements is connected using spherical joints to a plurality of neighboring pantomesh elements, wherein a first line that extends along one side of a first pantomesh element forms a first variable angle with a second line that extends along an opposite side of the first pantomesh element. In some embodiments, at least some of the pantomesh elements of the pantomesh are not isosceles trapezoidal elements. In some embodiments, the pantomesh is used to compress breast tissue during an MRI procedure. In some embodiments, the pantomesh is connected to one or more actuators that facilitate remote control of the amount of compression provided.

Abstract: Optical devices for use with a magnetic resonance imaging breast compression system include light wands and optical adapters that can releasably mate with grids. These devices, and their associated methods, may reduce or eliminate the need for biopsy by allowing for the differentiation of cancerous tumors, non-cancerous tumors, calcifications and cysts.

Abstract: Localization of a coil is provided for magnetic resonance (MR)-guided intervention. A multi-scale decomposition and characteristic transitions in the power spectra for the coil are used to determine a distribution of likelihood of the coil being at each of various locations and/or to determine a confidence in the position determination. For example, the power spectra along each axis is used to generate a likelihood distribution of the location of the coil. The power spectra are decomposited at different scales. For each scale, the modulus maxima reflecting transitions in the power spectra are matched using various criteria. A likelihood is calculated for each of the matched candidates from characterizations of the matched candidates. The likelihood distribution is determined from a combination of the likelihoods from the various scales.

Abstract: The present invention relates to the field of medical imaging. More particularly, embodiments of the invention relate to methods, systems, and devices for imaging, including for tomography-based applications. Embodiments of the invention include, for example, a computed tomography based imaging system comprising: (a) at least one wide-beam gray-scale imaging chain capable of performing a global scan of an object and acquiring projection data relating to the object; (b) at least one narrow-beam true-color imaging chain capable of performing a spectral interior scan of a region of interest (ROI) of and acquiring projection data relating to the object; (c) a processing module operably configured for: (1) receiving the projection data; (2) reconstructing the ROI into an image by analyzing the data with a color interior tomography algorithm, aided by an individualized gray-scale reconstruction of an entire field of view (FOV), including the ROI; and (d) a processor for executing the processing module.

Abstract: A method of forming an implant having a porous region replicated from scanned bone, the method comprising imaging bone with a high resolution digital scanner to generate a three-dimensional design model of the bone; removing a three-dimensional section from the design model; fabricating a porous region on a digital representation of the implant by replacing a solid portion of the digital implant with the section removed from the digital representation; and using an additive manufacturing technique to create a physical implant including the fabricated porous region.

Abstract: An MRI-compatible tip assembly for an MRI-compatible medical device includes a first tubular member, a second tubular member, a ring electrode, and a tip electrode. The tip electrode proximal end is secured to the first tubular member distal end. The second tubular member distal end is inserted through the ring electrode and is secured to the first tubular member proximal end. When assembled, the tip assembly is a substantially rigid structure. Each tubular member has a recessed portion for a tracking coil.

Abstract: A magnetic resonance imaging apparatus controls image reconstruction based on magnetic resonance signals collected when a peak of detected respiration level falls within an allowable range which changes based on a change in a plurality of peak values of a plurality detected respiration levels.

Abstract: A device for generating opposing fields for shielding an implant in the body of a patient during a magnetic resonance imaging, which device comprises a field generation unit with one or more field generation configured to generate field pulses and a control unit coupled with the field generation unit, and which is configured in such a manner that field pulses can be generated as opposing fields through which, within a spatial zone which contains the implant at least in sections, high-frequency electromagnetic field pulses and/or magnetic gradient field pulses used during the magnetic resonance imaging can be reduced or cancelled out in their intensity through superposition.

Abstract: Layers or coats of materials with high dielectric constant or permittivity with very low conductivity are inserted in between radiofrequency (RF) coil or coil's conductive elements and the sample to enhance the signal to noise ratio (SNR), improve image contrast, and reduce the specific absorption rate (SAR) of magnetic resonance imaging or magnetic resonance spectroscopy instruments. The embodiments of the present invention can be used as an auxiliary device to the standard pre-constructed RF coils or incorporated with RF coil constructions for enhancing RF coil performances in both transmission and reception.

Abstract: The receive coil arrangement includes an inner coil adjacent the part to be imaged so as to maximize the received MR signal and an outer coil, which may be the built in body coil of the magnet, connected by cable to the signal processing system. Both the coils are individually tuned to the common resonant frequency and the receive coil include an arrangement to halt current flow therein during the transmit stage. The first coil has no cable and is arranged to communicate the MR signal therein to the signal processing system through the outer coil by inducing the MR signal onto the outer coil. Despite inherent losses by interfering with the tuning of the loops and in the inductive coupling this magnifies the MR signal and makes the first coil wireless. Arrangements are provided for generating from the output of the second coil separate signals for separate channels of the signal processing unit.

Abstract: A method of treating a cancerous region in a breast of a patient comprising (i) imaging the breast in a three-dimensional coordinate system, (ii) stereotactically determining the location of the cancerous region in the breast, (iii) optionally determining the volume of the entire cancerous region to be treated, and (iv) while maintaining the breast in a three-dimensional coordinate system that is identical to or corresponds with the three-dimensional coordinate system used in (i), noninvasively exposing the cancerous region of the breast of the patient to a cancer-treatment effective dose of radiation; and equipment for use in such a method.

Abstract: Device and method for detecting electromagnetic fields occurring in imaging magnetic resonance tomography MRT/MRI tests. Relates to an implantable medical device (IMD) comprising a hermetically sealed housing, control unit(s), detection unit(s) for MRT interference fields connected/connectable to control unit(s) and to electrode(s) and/or to antenna(s) and/or coil(s), wherein the MRT interference detection unit contains at least one electro-optical converter which converts induced voltages from the electrode(s) and/or the antenna(s) and/or the coil(s) to optical signals, which are optically transmitted in a potential-free manner within the detection unit for MRT interference fields to an evaluation unit for the detection unit for MRT interference fields, and when a threshold for the optical signal and/or a predetermined periodic occurrence of the optical signals is exceeded, the evaluation unit triggers switching to an MRI-safe state or transmits a corresponding signal to the control unit(s).

Abstract: A system and method for performing magnetic resonance elastography (MRE] of a patient's breasts is provided. An MRE driver configured to be placed on the sternum of the patient is used to impart mechanical energy to the sternum, which in turn generates shear waves in at least one of the patient's breasts. Such a driver is amenable to use with standard breast radio frequency (RF] coils without the need for modification of the existing breast RF coil hardware.

Abstract: A hydraulic driver of a magnetic resonance elastography (MRE) system is provided. The hydraulic driver is adapted to be connected to at least a passive actuator for contacting with a subject. The hydraulic driver includes a pump, a hydraulic piston-cylinder unit operatively coupled to the pump, and a tube assembly. The tube assembly includes a proximal end in fluid communication with the hydraulic piston-cylinder unit and a distal end in fluid communication with the passive actuator. The passive actuator oscillates in response to hydraulic energy generated in a fluid in the hydraulic driver as the pump drives the piston forward and backward in the cylinder of the hydraulic piston-cylinder unit.

Abstract: A tracking device configured to be coupled to an interventional instrument and tracked by a magnetic resonance imaging system is provided. The tracking device includes, for example, paramagnetic and diamagnetic components that form first and second tracking members. When the tracking device is adjusted into a first arrangement, the tracking device will produce a local magnetic field in the presence of the magnetic field of an MRI system that is measurable by the MRI system. However, when the tracking device is adjusted into a second arrangement, the local magnetic field produced by the tracking device is reduced relative to the first arrangement, wherein the reduced local magnetic field produces substantially no magnetic field disturbances detectable by the MRI system. Images may be acquired of a patient in which the tracking device has been introduced and, using a numerical fitting method, an accurate location of the tracking device can be determined.

Abstract: An implantable parametric circuit enables local signal amplification and wireless transmission of RF signals in connection with magnetic resonance imaging systems. The parametric circuit detects RF signal detected during magnetic resonance imaging procedure, amplifies the detected RF signal, and transmits the amplified RF signal in a wireless manner to an external pick-up coil. The parametric amplifier is also configured to use another RF signal generated by an external source as the primary power source. As a result, implanted or catheter coils could be used as a wireless signal transducer without the need for a battery or a power connection.

Abstract: The present invention is directed toward an acoustic, piezoelectric, electric, electro-mechanical or pneumatically driven surface drum driver, in mechanical engagement with a biopsy or acupuncture needle device and a method for its use for diagnosis of small e.g. 100 microns, tumors via the production of magnetic resonance elastographic images (MRE), without artifact production, in a magnetic resonance imaging (MRI) machine. In a second embodiment, the invention is directed toward an acoustically, pneumatically, piezoelectrically, electrically and/or electro-mechanically driven acupuncture needle, useful for simulating manual single-needle acupuncture treatments via a non-manually manipulated acupuncture needle; and further to a device and process for determination, using twin pneumatically driven surface drivers, of organ stiffness, e.g. brain stiffness, which can be quantified so as to be useful in elucidating and quantifying brain cognitive state, e.g.

Abstract: The present invention discloses an imaging device within an MRI. In a magnetic resonance imaging system, a spatially fixed coupled imaging device (SFCID) for producing combined anatomical and real time functional light images, the SFCID functionally incorporates a maneuverable imaging system MIS with a coupled imaging system CIS.

Abstract: A novel method and system for employing device tracking with a magnetic resonance imaging system. In accordance with one aspect of the present technique, a method for tracking the location of a device and generating an image using magnetic resonance imaging includes applying a combined imaging and tracking pulse sequence, in the presence of a magnetic field gradient, wherein the combined imaging and tracking sequence comprising a radiofrequency excitation pulse. The method further includes collecting tracking data based on a magnetic resonance tracking signal resulting from the radiofrequency excitation pulse, wherein the magnetic resonance tracking signal is returned from a tracking coil mounted in the device. The method also includes collecting imaging data based on a magnetic resonance imaging signal resulting from the radiofrequency excitation pulse, wherein the magnetic resonance imaging signal is returned from an imaging coil.

Abstract: Methods and apparatus for screening patients prior to deep brain stimulation to treat cognitive function are provided. One or more patient parameters are processed to produce results. A comparison of the results to a threshold indicates the applicability of the deep brain stimulation therapy.

Abstract: A method of operating a magnetic resonance imaging scanner for imaging the heart of a patient comprising inducing apnoea in the patient; sensing an electrical heart waveform; in response thereto moving the chest wall of the patient to a desired location; and triggering the scanner to image.

Abstract: The present invention is directed to a system and method for performing tissue, preferably bone tissue manipulation. The system and method may include implanting markers on opposite sides of a bone, fractured bone or tissue to facilitate bone or tissue manipulation, preferably in-situ closed fracture reduction. The markers are preferably configured to be detected by one or more devices, such as, for example, a detection device so that the detection device can determine the relative relationship of the markers. The markers may also be capable of transmitting and receiving signals. An image may be captured of the bone or tissue and the attached markers. From the captured image, the orientation of each marker relative to the bone fragment may be determined. Next, the captured image may be manipulated in a virtual or simulated environment until a desired restored orientation has been achieved. The orientation of the markers in the desired restored orientation may then be determined.

Abstract: A system and method for generating an electrophysiological map are provided. The system includes an electronic control unit (ECU) configured to receive a signal generated by an electrode disposed at a position on an external surface of the body and indicative of electric potential. The ECU is further configured to identify a surface boundary of an object of interest within the body using an image of the object. The ECU is further configured to identify intervening objects along a pathway between the position on the external surface and the surface boundary of the object of interest from one or more images of the pathway. The ECU is further configured to obtain an impedance value for each of the intervening objects and to determine an electric potential at the surface boundary of the object of interest responsive to the signal from the electrode and the impedance values of the intervening objects.

Abstract: A system and method for measuring the shape of an object using a magnetic induction radio sensor involves at least partially enclosing the object with a magnetic loop antenna of the magnetic induction radio sensor, where the inductance of the magnetic loop antenna depends on the shape of the object, and providing a particular capacitance at an antenna matching circuit coupled to the magnetic loop antenna in response to the inductance of the magnetic loop antenna such that the magnetic loop antenna and the antenna matching circuit form a resonant circuit and the resonant circuit has a fixed resonant frequency, where the particular capacitance is used to measure the shape of the object.

Abstract: A method, including constructing a simulated surface of a body cavity, and pressing a distal end of a probe against a wall of the body cavity. While pressing the distal end against the wall, position measurements are accepted from the probe indicating a position of the probe within the body cavity, and force measurements are accepted from the probe indicating a force between the distal end and the wall. A distortion in the simulated surface is created at the position indicated by the position measurements, so as to form a distorted surface, upon detecting that the force measurements exceed a predefined amount. The distorted surface is then displayed.