Abstract: A method of measuring a specific absorption rate (SAR) of a hip joint implant using magnetic resonance imaging (MRI), includes: arranging the hip joint implant in a human lower body-shaped phantom; arranging an electric field sensor around the hip joint implant; providing radio frequency (RF) energy according to an MRI sequence to the human phantom; and calculating the SAR of the hip joint implant from strength of an electric field measured by the electric field sensor.

Abstract: Systems and methods for assessing expansion of an abnormality are provided. A first input medical image of a patient depicting an abnormality at a first time and a second input medical image of the patient depicting the abnormality at a second time are received. The second input medical image is registered with the first input medical image. The abnormality is segmented from 1) the first input medical image to generate a first segmentation map and 2) the registered second input medical image to generate a second segmentation map. The first segmentation map and the second segmentation map are combined to generate a combined map. Features are extracted from the first input medical image and the registered second input medical image are based on the combined map. Expansion of the abnormality is assessed based on the extracted features using a trained machine learning based network. Results of the assessment are output.

Abstract: A magnetic resonance imaging device having a field generation unit configured to provide a magnetic field in an imaging volume of the magnetic resonance imaging device. The field generation unit has at least one magnet. A surface of the field generation unit directed towards the imaging volume of the at least one magnet has a concave shape, wherein a direction of access to the imaging volume is oriented essentially perpendicular to a main direction of magnetic field lines in the imaging volume.

Abstract: This disclosure generally relates to stable water isotope labeling followed by detection via MRI (swiMRI), including deuterium MRI (dMRI) and 17O MRI, for visualizing rapidly dividing immune cells within target and/or lymphoid organ/s and/or tissues affected by chronic graft-versus-host disease (cGVHD). Using deuterated water labeling, followed by dMRI, a distinction in deuterium signal was detected in a target organ (e.g. liver) of the cGVHD-affected mice compared to unaffected mice, i.e. syngeneic HSCT recipient mice, where the host and donor are matched, and normal (unmanipulated) mice.

Abstract: Provided herein are systems, devices, assemblies, and methods for generating exciter signals, for example, to activate a remotely located tag. The systems, devices, assemblies, and methods find use in a variety of application including medical applications for the locating of a tag in a subject.

Abstract: The present disclosure provides medical devices having MRI-compatible circuitry. Preferably, the devices do not project an enlarged profile, yet their position can be determined during an iMRI procedure. Illustrative embodiments of such a device can include a base surface, a first conducting layer disposed on the base surface, a first insulating layer disposed over at least a portion of the first conducting layer, and a second conducting layer disposed over at least a portion of the first insulating layer.

Abstract: A method for referencing a tracking system's coordinate frame to a rigid body's coordinate frame is disclosed. The method involves obtaining a 3D model depicting some of the surfaces of the rigid body. A probe is provided with an affixed tracking reference component. A second tracking reference component is attached to the rigid body. The method involves tracking locations of the probe as it moves along surfaces of the rigid body and then determining a transform that relates the probe locations to the 3D model of the rigid body. In one embodiment the rigid body is a dental mandible or maxilla of a patient and the 3D model is a surface extracted from a computed tomography image of the patient's jaw and teeth.

Abstract: Disclosed is an instrument assembly usable in a procedure. The instrument includes a connection for a working portion and to a tool handle. A tracking device or assembly may be associated with the instrument for determining a position of the instrument.

Abstract: A marker delivery device including a delivery catheter, a marker, and a push rod. The delivery catheter is adapted to be inserted into a biopsy site and having a discharge opening. The marker having a coating layer disposed on the surface of a core. The coating layer includes an adhesive with a plurality of microbubbles. The microbubbles are configured to enhance visibility of the marker under ultrasound imaging. The marker is positioned inside the delivery catheter near the discharge opening. The push rod is positioned within the delivery catheter and is adapted to deploy the marker from the delivery catheter into the biopsy site.

Abstract: Provided herein are systems, devices, assemblies, and methods for generating exciter signals, for example, to activate a remotely located tag. The systems, devices, assemblies, and methods find use in a variety of application including medical applications for the locating of a tag in a subject.

Abstract: An apparatus for measuring bio-information in a non-invasive manner includes: a pulse wave sensor configured to measure a plurality of pulse wave signals having different wavelengths from an object; a contact pressure sensor configured to measure contact pressure of the object while the plurality of pulse wave signals are measured; and a processor configured to obtain an oscillometric waveform based on the contact pressure and the plurality of pulse wave signals having the different wavelengths, and obtain bio-information based on the oscillometric waveform.

Abstract: A multi-channel RF transmitter system including a magnetic resonance imaging device, a multi-channel RF coil array, a control computer receiving required parameters from a user, producing triggering and clock signals and synthesizing input data required for each channel of RF coil array according to imaging scenario to be realized, an interface control module producing basic band MRI signals according to data from the control computer, a signal modulator and control module for modulating MRI signals produced at the interface control module into radio frequency and distribution to channels, a power/data distribution module distributing the produced signals and required DC power, a RF power amplifier module converting digital signal coming from the power/data distribution module into analog signal, amplifying it and transmitting to members of the coil array, a feedback line for track and correction of any errors in RF signal transmitted to the coil array by the power amplifier module.

Abstract: Polar hydrophobic ionic materials and, in particular, polar hydrophobic ionic polyurethanes having a minimum ratio of hydrophobic and anionic components to the remainder of the polymer components are provided that exhibit reduced IgG Fab exposure.

Abstract: A method for decontaminating a tube includes positioning an antenna at least partially within the tube. The tube is positioned at least partially within a living body. The method also includes decontaminating the tube by causing the antenna to emit electromagnetic waves having a frequency from about 10 GHz to about 100 GHz for a time duration that is less than or equal to 60 seconds. The electromagnetic waves cause a temperature of the living body proximate to the tube to increase from about 0.1° C. to about 3° C. so as to not substantially damage the living body.

Abstract: A sheath for producing a fully sealed access to the interior of a vessel of an animal or human body comprises a base sheath having a tubular body defining a pass-through channel. The base sheath is adapted to be inserted into the vessel through a vessel aperture. A wall of the tubular body of the base sheath has a through channel. This channel extends in the wall from the distal end towards the proximal end. The channel can be present separately from the pass-through channel of the base sheath or can form a sideways extension of the pass-through channel, at least at the distal end. Such through channel is adapted to conduct blood from the vessel to the proximal end of the sheath when the sheath has been inserted into a vessel.

Abstract: Navigation assistance systems and methods for use with a surgical instrument to assist in navigation of a surgical instrument during an operation. The system may include sensors that may observe the patient to generate positioning data regarding the relative position of the surgical instrument and the patient. The system may retrieve imaging data regarding the patient and correlate the imaging data to the positioning data. In turn, the position of the surgical instrument relative to the imaging data may be provided and used to generate navigation date (e.g., position, orientation, trajectory, or the like) regarding the surgical instrument.

Abstract: The present invention discloses a system to control a movement of a magnetic capsule using an external magnet control system. The external magnet control system includes more than one external magnetic balls, and at least one external magnetic ball can be moved freely in five degrees of the freedom.

Abstract: An implantable medical device (IMD) is described that automatically detects the presence of an external magnetic field, such as that generated by an MRI device. The IMD includes a torque sensor configured to generate an output signal that varies as a function of a torque imposed on the torque sensor by an external magnetic field and a control module configured to control operation of the implantable medical device based on the signal output of the torque sensor.

Abstract: The present invention discloses a method to move a magnetic capsule linearly both horizontally and linearly in a very controllable fashion, wherein the direction of a combined external magnetic field, the force experienced by the magnetic capsule, the movement direction of the capsule and magnetic direction of the magnetic capsule can be all aligned in parallel to each other.

Abstract: A detachable biosignal complex sensor includes a clip type structure including: a circuit module configured to receive a biosignal of a subject and perform signal processing on the biosignal, a first plate, and a second plate having an end thereof which is rotatably connected to an end of the first plate so that the clip type structure is configured to be fastened to an item; and a sensor and electrodes provided on outer surfaces of the first plate and the second plate and configured to obtain the biosignal and transmit the obtained biosignal to the circuit module.

Abstract: While a catheter that includes (i) a catheter body, and (ii) a catheter shaft, which includes a sensor and which is disposed inside a lumen of the catheter body, is inside a body of a subject, a coordinate system of the sensor is registered with a coordinate system of an imaging system, using (a) a calibration image, acquired by the imaging system, that shows an indication of a distal end of the catheter body, and (b) a signal from the sensor, but not using any indication of the sensor shown in the calibration image. Using the registering, a visual output is generated. Other embodiments are also described.

Abstract: The present teaching relates to surgical procedure assistance. In one example, a first image of an organ having a lesion is obtained prior to a surgical procedure. Information related to a pose of a surgical instrument at a first location with respect to the lesion is received from a sensor coupled with the surgical instrument. A visual environment having the lesion and the surgical instrument rendered therein is generated based on the first image and the information received from the sensor. A second image of the organ is obtained when the surgical instrument is moved to a second location with respect to the lesion during the surgical procedure. The second image captures the lesion and the surgical instrument. The pose of the surgical instrument and the lesion rendered in the visual environment are adjusted based, at least in part, on the second image.

Abstract: Provided herein are systems, devices, assemblies, and methods for generating exciter signals, for example, to activate a remotely located tag. The systems, devices, assemblies, and methods find use in a variety of application including medical applications for the locating of a tag in a subject.

Abstract: A shielded connection line for a magnetic resonance tomography system includes a signal conductor, a shield for the signal conductor, and a plug-in connector. The plug-in connector has a large number of connection contacts that are arranged in a two-dimensional matrix and are electrically insulated from each other in the plug-in connector. The signal conductor is in galvanic contact with a first connection contact, and three second connection contacts adjacent to the first connection contact and surrounding the first connection contact are galvanically connected to the shield.

Abstract: A system for operating a downhole tool includes a tag carrier; a RFID tag coupled with the tag carrier; and a control sub having a bore extending therethrough, the control sub comprising: an antenna located adjacent to the bore; and a stop for catching the tag carrier, wherein: the radio frequency identification tag is coupled with the tag carrier in relation to the stop and the antenna such that the radio frequency identification tag is aligned with the antenna when the tag carrier is caught in the stop, and the stop is operable to allow passage of the tag carrier through the stop after the tag carrier is caught by the stop.

Abstract: A system for operating a downhole tool includes a tag carrier; a RFID tag coupled with the tag carrier; and a control sub having a bore extending therethrough, the control sub comprising: an antenna located adjacent to the bore; and a stop for catching the tag carrier, wherein: the radio frequency identification tag is coupled with the tag carrier in relation to the stop and the antenna such that the radio frequency identification tag is aligned with the antenna when the tag carrier is caught in the stop, and the stop is operable to allow passage of the tag carrier through the stop after the tag carrier is caught by the stop.

Abstract: Apparatus and methods for measuring radiation levels in vivo in real time. Apparatus and methods include a scintillating material coupled to a retention member.

Abstract: A wireless radio frequency coil for magnetic resonance imaging (MRI) is provided. The wireless radio frequency coil including a wireless radio frequency coil unit configured to transmit, receive or transmit and receive a radio frequency signal; a power supply configured to provide a power voltage for operation of the wireless radio frequency coil unit; a switch connected to the power supply and the wireless radio frequency coil unit; a sensor configured to detect signals discharged from a space in which the wireless radio frequency coil unit is located; and a controller configured to provide or shut off the power voltage to the wireless radio frequency coil unit by controlling the switch according to a result obtained from the sensor.

Abstract: An elongated flexible medical device is inserted into a patient's body via a natural orifice, and advanced through the natural orifice to a location proximate innervated tissue that influences renal sympathetic nerve activity. The medical device can be advanced into a body organ and to a location within the organ proximate the innervated tissue. The organ may comprise an organ of the gastrointestinal tract or urinary tract. The medical device may be advanced through and beyond an access hole in a wall of the organ, and situated at a location proximate the innervated tissue. One or both of imaging and ablation energy is delivered from a distal end of the medical device to the innervated tissue. Innervated renal tissue can be ablated using various forms of energy, including RF energy, ultrasound energy, optical energy, and thermal energy.

Abstract: Systems and methods are described herein for tracking, localization or controlling an elongate instrument or other medical instrument in an image or patient.

Abstract: A hyperpolarized liquid contrast agent is for use in a MRT device. The liquid contrast agent passes through a conduit of a MW resonator in the magnetic field of the MRT device. A microwave with a frequency of at least 40 GHz couples into the MW resonator for polarizing the liquid contrast agent upon passage through the conduit in the MW resonator using DNP. The contrast agent is polarized in a continuous passage in the MW resonator and administered immediately. A MW mode is formed in the MW resonator which has an antinode in the magnetic field strength and a node in the electric field strength. The power of the introduced microwave and coupling of the microwave into the resonator are adjusted such that in the area of the line, an amplitude of the MW magnetic field strength B 1 ? 1.5 · 10 - 2 ? Ts ? 1 T 1 , e results, wherein T1,e is the relaxation time of the DNP-active electrons.

Abstract: Active MRI compatible interventional devices, such as catheters, include at least one RF antenna so that they are visible under MRI analysis. However, metallic structures within intravascular devices may heat up significantly during interventional MRI procedures due to eddy current formation over the conductive transmission lines. The electrical field coupling that occurs between interventional devices and RF signals depend on the position and orientation of interventional device within the bore and the insertion length of the interventional device. The system detects an induced current signal during RF transmission phase and selectively adjusts the impedance value associated with the interventional device by using a varactor and integrated circuit components in such a manner that the currents induced in the interventional device are below a threshold current level, thereby controlling current levels and heating in the interventional device.

Abstract: A system for determining the spatial distribution of magnetic particles in an examination area. Magnetic field generator generates a spatially inhomogeneous gradient magnetic field with at least one region with a low field strength in which the magnetization of the particles is in a state of non-saturation, whereas they are in a state of saturation in the remaining region. By an arrangement to shift the area with a low field strength within the examination area, a change in the magnetization of the magnetic particles is brought about which can be detected from outside by a detector. At least one of the magnetic field generator, the arrangement and the detector are arranged at least partially on a medical instrument.

Abstract: A method for hyperpolarizing nuclei contained in an MR (=magnetic resonance) agent using Brute Force, has the steps of a) providing a sample (1), including the MR agent, optionally dissolved in a solvent, and a relaxation agent (2); and b) exposing the sample (1) to a magnetic field B0, with B0?0.5 T, and a cryogenic temperature Tcr, with Tcr?5K. The method is characterized in that the relaxation agent (2) is a particulate relaxation agent (2) having particles of a grain size of 20 ?m or less, with a volume content of these particles of at least 1% within the sample. An improved Brute Force hyperpolarization method is thereby provided, which is broadly applicable and simple to perform.

Abstract: An environmental chamber includes a testing tub in which a testing space is formed. The testing tub has a front wall, a left sidewall, a right sidewall, a rear wall, and a ceiling part, and is divided into a lower tub part and an upper tub part by a dividing surface extended in a direction inclined downwardly and frontwardly. The left and right sidewalls are respectively divided into two portions by the dividing surface. An inner surface of the upper tub part includes at least a part of an inner surface of each of the ceiling part, the front wall, the left sidewall, and the right sidewall. The upper tub part is supported by the lower tub part to be able to open the testing space.

Abstract: A magnetic field correction system including apparatus and method for adjusting a magnetic field is provided, for example to enhance the uniformity of the field in a Nuclear Magnetic Resonance (NMR) operation. The system is of an electronic “shimming” type. The layout of the wires of the shim coils is simplified to conserve working space inside a magnet, such as an NMR magnet. The complexity of the shimming system is removed from the coils and transferred to the current controlling electronics. The current paths do not require cross-over points, and groups of parallel wires are arranged such that the wire groups have axes with different directional orientations. By deploying such shim wire groups in differently oriented axial directions, a compact shimming apparatus is provided for generating a controllable corrective magnetic field for adjusting a main original field, such as to enhance the homogeneity of the main field.

Abstract: A guidewire (100) for use with interventional magnetic resonance imaging has a guidewire body (102) having a distal end and a proximal end and reserving a space therein, a dipole antenna (108) disposed in the space reserved within the guidewire body, the dipole antenna being adapted to be electrically connected to a signal processing system through a first signal channel (110) through the proximal end of the guidewire body, and a loop antenna (112) disposed in the space reserved within the guidewire body toward the distal end of the guidewire body, the loop antenna (112) being adapted to be electrically connected to the signal processing system through a second signal channel (114) through the proximal end of the guidewire body. The dipole antenna and the loop antenna are each constructed to receive magnetic resonance imaging signals independently of each other and to transmit received signals through the first and second signal channels, respectively, to be received by the signal processing system.

Abstract: A method for estimating receiver coil sensitivity in a magnetic resonance (MR) system having a plurality of coils in a coil array including a reference coil, including steps of estimating receiver coil sensitivity in each of the plurality of coils in the coil array of the MR system using one of an electromagnetic field method, a bias field method, and a uniform transmit field method. Each of the plurality of coils in the coil array includes one or more of a surface coil, a volume coil, a set of coil arrays, or an antenna element of a coil array. The method further includes steps of obtaining a reference image using the reference coil; generating a measured sensitivity map using the reference coil; and for each of the plurality of coils of the coil array, calculating a receiver coil sensitivity map.

Abstract: Tracking based on the gradient fields of magnetic resonance imaging (MRI) scanners based on passive operation of the tracking system without any change of the scanner's hardware or mode of operation. To achieve better tracking performance, a technique to create a custom MRI pulse sequence is disclosed. Through this technique any standard pulse sequence of the scanner can be modified to include gradient activations specifically designated for tracking. These tracking gradient activations are added in a way that does not affect the image quality of the native sequence. The scan time may remain the same as with the native sequence or longer due to the additional gradient activations. The tracking system itself can use all the gradient activations (gradient activations for imaging and gradient activations for tracking) or eliminate some of the gradients and lock onto the specific gradient activations that are added to the custom pulse sequence.

Abstract: The present invention is directed to a device and method for opening obstructed body internal passages and for sensing and characterizing tissues and substances in contact with the device. In general, the device comprises a catheter tube capable of inducing vibrations in a guidewire contained therein, wherein said vibrations of the guidewire are utilized for opening a passage through an occlusion. The in-vivo vibrations may be induced by means of a magnetic field actuating means and a guidewire comprising magnetic coupling means, or by means of transducers, which may be also used for the sensing. The invention also relates to the field of minimal invasive catheterization, particularly an apparatus for opening and/or removing obstructions occluding body internal passages by means of an active guidewire comprising a coil to which an alternating voltage can be applied. In that way the guidewire can vibrate if an external magnetic field is applied.

Abstract: A catheter-mounted, expandable or set in position, coil for magnetic resonance imaging. The coil having a catheter sheath including an elongated tube with a central axis, the catheter sheath having an opening at an end thereof; an expandable coil including a conductive material connected to an expansion mechanism which, when deployed, maintains the expandable receive coil shape; and a cable running through the catheter sheath, the cable being electrically connected to the coil inductive loop.

Abstract: An interface device enables an intracavity probe to be used with a magnetic resonance (MR) system for the purpose of obtaining images or spectra of a region of interest within a cavity of a patient. The probe includes a shaft, a balloon at one end thereof, and a coil loop within the balloon. The coil loop preferably includes two drive capacitors and a tuning capacitor, all of which in series. A junction node between the drive capacitors serves as a ground for electrically balancing the coil loop. Diametrically opposite the junction node, the tuning capacitor enables the coil loop to resonate at the operating frequency of the MR system. Across each drive capacitor is connected an output cable having an electrical length of SL+n(?/4). The output cables terminate in a plug that is used to connect the coil loop to the interface device.

Abstract: An implantable stimulation system comprises a stimulator for generating electrical stimulation and a conductive stimulation lead having a proximal end electrically coupled to the stimulator, wherein at least a first component of the impedance looking into the stimulator is substantially matched to the impedance of the stimulation lead. At least one distal stimulation electrode is positioned proximate the distal end of the stimulation lead.

Abstract: A catheter device for deploying a local magnetic resonance imaging (MRI) coil is provided. The catheter device includes an outer catheter shaft having a lumen extending from a proximal end to a distal end and an inner catheter shaft having a lumen extending from a proximal end to a distal end. The outer and inner catheter shafts are movably engaged such that one can move relative to the other. A plurality of non-metallic filaments are coupled on one end to the outer catheter shaft and coupled on another end to the inner catheter shaft. The plurality of non-metallic filaments are intertwined to form a braid, to which a local MRI coil is coupled. The local MRI coil is configured to have a circular shape when the braid is in a deployed position. Additionally, motion tracking coils can be coupled to the braid to provide motion tracking information for motion compensation.

Abstract: A method of displaying an image of the location of one or more low voltage structures in tissue is provided. The method includes receiving electrical mapping data corresponding to a portion of the tissue. The method further includes generating an image using the electrical mapping data. Electrical mapping values within at least one voltage range having two endpoints that bound the upper and lower limits of the voltage range are distinguishable from electrical mapping values outside the at least one voltage range. The two endpoints are selected to distinguish the one or more low voltage structures of the tissue from other portions of the tissue.

Abstract: A method, including capturing, from an imaging system, a three-dimensional (3D) image of a body cavity, and using the captured 3D image to construct a simulated surface of the body cavity. A probe having a location sensor is inserted into the body cavity, and in response to multiple location measurements received from the location sensor, multiple positions are mapped within respective regions of the body cavity so as to generate respective mapped regions of the simulated surface. Based on the simulated surface and the respective mapped regions, one or more unmapped regions of the simulated surface are delineated, and the simulated surface of the body cavity is configured to indicate the delineated unmapped regions.

Abstract: The invention relates to a probe (10) for an implantable medical device. The probe has a distal end (2) and a proximal end (3), and the probe (10) moreover comprises an electrode (1) at the distal end. The electrode is connected to a wire (5) extending from the electrode to the proximal end of the probe, where the resistivity of the wire is non-uniform along the length of the wire. The wire may have high resistivity at the distal end of the probe and low resistivity wires elsewhere. The high resistivity wires reduce the peak current density in the tissue of an implanted device, and thus prevents destructive heating and/or undesired stimulation of tissue during MRI examination. This highly contributes to MR safety which is a highly desired feature for these implantable electrical stimulation devices.

Abstract: An adaptation probe for insertion into implanted electrode devices of active medical implants to enable them for use in high-frequency magnetic alternating fields of MRI systems comprises an elongated, flexible probe body, and at least one electrical assembly, which has one or more electrical components connected to an interface, in the probe body, and which can be electrically connected to a supply lead of the electrode device such that the electrically properties of the electrode device can be adapted, in particular the frequency-dependent resistance, impedance, capacitance, or inductance thereof.

Abstract: A catheter for magnetic resonance (MR) guided procedures comprising: a catheter body having a lumen for accommodating an intravascular device; a magnetic coupling component in the catheter body, the magnetic coupling component being designed to magnetically couple with a conductive length on the intravascular device, the magnetic coupling resulting in a signal; the catheter having a connection to deliver the signal to a processor.

Abstract: An apparatus for percutaneously implanting a localization wire into a tissue mass comprises a cannula with a preloaded localization wire having a distal end and at least one anchor. An actuator is in operable communication with the cannula and is configured for operation between a charged condition and a discharged condition to retract the cannula toward a retracted position to expose the distal end and the at least one anchor of the localization wire to the tissue mass, without inducing movement of the localization wire, and with the cannula being removable from the localization wire in its entirety.