Abstract: A method and a device for nondestructively detecting an elasticity of a viscoelastic medium are provided. The method includes: detecting a pressure applied to the viscoelastic medium by an ultrasonic transducer probe; in response to the pressure satisfying a predetermined condition, triggering detecting the elasticity of the viscoelastic medium; driving the ultrasonic transducer probe with a low-frequency vibration by a vibrator so as to produce an elastic wave in the viscoelastic medium; producing an ultrasonic wave by the ultrasonic transducer probe, and transmitting the ultrasonic wave to the viscoelastic medium; collecting an ultrasonic echo; calculating an elastic parameter of the viscoelastic medium according to the collected ultrasonic echo.

Abstract: A method and a device for nondestructively detecting an elasticity of a viscoelastic medium are provided. The method includes: driving an ultrasonic transducer probe with a low-frequency vibration by a vibrator so as to produce an elastic wave in the viscoelastic medium; producing an ultrasonic wave by the ultrasonic transducer probe, and transmitting the ultrasonic wave to the viscoelastic medium; collecting an ultrasonic echo when the elastic wave is propagated in the viscoelastic medium and the ultrasonic transducer probe stops or almost stops vibrating; calculating an elastic parameter of the viscoelastic medium according to the collected ultrasonic echo.

Abstract: A method and a device for nondestructively detecting an elasticity of a viscoelastic medium are provided. The method includes: acquiring with an ultrasonic imaging probe an ultrasonic image of the viscoelastic medium; determining an area to detect the elasticity of the viscoelastic medium according to the ultrasonic image; driving the ultrasonic transducer probe with a low-frequency vibration by a vibrator so as to produce an elastic wave in the viscoelastic medium; producing an ultrasonic wave by the ultrasonic transducer probe, and transmitting the ultrasonic wave to the viscoelastic medium; collecting an ultrasonic echo; calculating an elastic parameter of the viscoelastic medium according to the collected ultrasonic echo.

Abstract: Rotational intravascular ultrasound (IVUS) imaging devices and systems are provided. The IVUS imaging devices include catheters having a rotating drive cable with a transducer disposed at a distal end thereof for imaging a bodily vessel of interest. In some embodiments, a lubricious coating is applied on the drive cable to promote uniform rotation of the drive cable and the transducer. In some embodiments, the drive cable is coated with a polymer layer to promote uniform rotation of the drive cable and the transducer. In some embodiments, radiopaque markers are affixed on the drive cable for accurate placement of the transducer within of the vessel and for accurate measurement of internal dimensions and lesion lengths within the body of the patient.

Abstract: Devices, systems, and methods for catheterization through angionavigation, cardionavigation, or brain navigation to diagnose or treat diseased areas through direct imaging using tracking, such as radiofrequency, infrared, or ultrasound tracking, of the catheter through the patient's vascular anatomy. A steerable catheter with six degrees of freedom having at least a camera and fiber optic bundle, and one or more active or passive electromagnetic tracking sensors located on the catheter is guided through the vascular system under direct imaging. The direct imaging can be assisted with at least one of MRA imaging, CT angiography imaging, or 3DRA imaging as the roadmap acquired prior to or during 3D stereoangiovision. The system comprises RF transceivers to provide positioning information from the sensors, a processor executing navigation software to fuse the tracking information from the tracking sensors with the imaging roadmap, and a display to display the location of the catheter on the roadmap.

Abstract: A system and method for qualitative analysis of time progressive signals, comprising: a qualitative signal analysis module, comprising at least a processor, a memory, and a long term storage device; and an output processor module comprising at least a processor a memory and a network interface has been devised. The qualitative signal analysis module retrieves signal data over time and applies pre-programmed protocols to compare multiple aspects of the signal data to derive meaningful data. The output processor module encodes data generated by the qualitative signal analysis module for use in subsequent analytical steps such as further manipulation, classification or long term storage.

Abstract: Scissors including a pair of shanks with one end forming an upper shear blade and a lower shear blade and with the other end of the pair of shanks forming handles, the handles being opened and closed centered about a pivot where the shanks intersect and causing the upper shear blade and lower shear blade to open and close, and screw for loosely fastening the pivot with a degree of freedom so that the screws do not interfere with sliding of the blades when cutting an object, at least one of the upper shear blade and the lower shear blade being formed by an alloy having an elastic deformation ability of 0.2% or more.

Abstract: A variable-frequency light source is configured to emit a light beam and modulate a frequency of the light beam. A fiber optic cable is attached to the variable frequency light source. The fiber optic cable is configured to receive the light beam at an inlet and pass the light beam to an exit. Multiple optical detectors are attached to the fiber optic cable. Each of the optical detectors is configured to detect a specified frequency of light that is backscattered through the fiber optic cable. An actuation mechanism is attached to the fiber optic cable. The actuation mechanism is configured to deform the fiber optic cable in response to a stimulus.

Abstract: Systems and methods for relaying electrical signals representing acoustic response of a volume of tissue to light and ultrasound stimulation. In an embodiment, a plurality of ultrasound transducers receive acoustic energy from the volume and generate electrical energy, which is transmitted via an electrical path to a relay system. The ultrasound transducers are operated at a wide band frequency of at least 1 MHz to 5 MHz to receive acoustic energy from the volume of tissue responsive to light stimulation and at a narrower band frequency to receive acoustic energy from the volume of tissue responsive to acoustic stimulation. The relay system relays the electrical signals to an optoacoustic system or an ultrasound instrument for further processing depending on whether the electrical signals resulted from ultrasound or light stimulation. In an embodiment, optoacoustic, ultrasound, or other images are generated from the electrical signals and may be coregistered, overlayed, or displayed.

Abstract: Disclosed are devices, systems, and methods for determining the dipole densities on heart walls. In particular, a triangularization of the heart wall is performed in which the dipole density of each of multiple regions correlate to the potential measured at various located within the associated chamber of the heart. To create a database of dipole densities, mapping information recorded by multiple electrodes located on one or more catheters and anatomical information is used. In addition, skin electrodes may be implemented. Additionally, one or more ultrasound elements are provided, such as on a clamp assembly or integral to a mapping electrode, to produce real time images of device components and surrounding structures.

Abstract: A method of making a superelastic medical device with a radiopaque marker includes threading a radiopaque marker having an elongated shape over a wire comprising a shape memory alloy. After the threading, the wire is secured in a predetermined configuration to a mandrel. While secured to the mandrel, the wire is heat set in an environment comprising an inert gas so as to impart a memory of the predetermined configuration to the wire and superelastic properties to the shape memory alloy. A superelastic medical device including the radiopaque marker is thus formed.

Abstract: A device for thrombolytic therapy is provided. The device includes an elongate catheter with a distal end portion and a proximal end portion and a first lumen extending through both distal and proximal end portions. The distal end portion of the catheter includes an echogenic tubular potion that defines or surrounds a portion of the first lumen. An expandable balloon coaxially surrounds the tubular portion. The tubular portion additionally includes a plurality of indentations defined upon an outer surface thereof.

Abstract: A probe tip assembly for receiving at least a portion of an ultrasound probe therein includes a body having a proximal end and an opposing distal end. A first opening may be located at the proximal end of the body. The first opening may be sized and shaped to receive at least a portion of the probe therein. A second opening may be proximate the distal end of the body. A membrane may cover the second opening.

Abstract: An ultrasound probe including a housing, a head part provided on the housing so as to enable expansion and contraction, an array provided in the housing and having one or more transducers, a rotary part provided at a rear surface of the array to rotate the array, a pressing part configured to expand the head part by applying pressure to the head part, and a control part, when the head part is inserted into a target object, configured to allow the array to control the pressing part such that the head part is expanded, and allow the array to be rotated in the expanded head part, by controlling the rotary part, thereby relieving pain involved with insertion of the ultrasound probe.

Abstract: Described are embodiments of devices and methods for imaging a body conduit, such as a blood vessel. In particular embodiments, the catheter has a chamber within which is a transducer mounted to a pivot mechanism. A coil provides a pivot force to the transducer. A magnet is attached to the transducer and is receptive of a torque applied by a magnetic field produced by energizing of the coil. A driving mechanism receives an impact from the pivot member and causes the pivot mechanism to rotate about a rotation axis.

Abstract: A system and method for imaging a target in a patient's body uses a pre-acquired image of the target and a catheter having a position sensor and an ultrasonic imaging sensor. The catheter is placed in the patient's body and positional information of a portion of the catheter in the patient's body is determined using the position sensor. The catheter is used to generate an ultrasonic image of the target using the ultrasonic imaging sensor. An image processor is used for determining positional information for any pixel of the ultrasonic image of the target and registering the pre-acquired image with the ultrasonic image; and a display is used for displaying the registered pre-acquired image and ultrasonic image.

Abstract: Embodiments of the invention relate generally to systems and methods for providing embolic protection to a medical procedure by filtration of debris generated by the medical procedure. The system and methods include an embolic protection device having an ultrasound transducer for assisting in intravascular navigation of the device.

Abstract: Ultrasound medical apparatus and ultrasound diagnosis apparatus are provided capable of indwelling in the observation object at a desired position of the inner cavity of the subject. The ultrasound medical apparatus according to the embodiments include a sheath, a capsule body unit, and a fixation mechanism. The sheath is inserted into the inner cavity of a subject, having an outer peripheral surface that contacts the inner wall surface of the inner cavity of the subject with a liquid filled inside thereof. The capsule body unit is inserted into the sheath, and configured to store an ultrasound transducer that transmits and receives ultrasound waves to and from the subject. The fixation mechanism is provided in at least one of the capsule body unit and the sheath, to fixedly arrange the capsule body unit at a desired position in the sheath.

Abstract: An apparatus includes a power source, a pulse generator, a light source, a guidewire, an optical fiber, and a connector. The pulse generator is in electrical communication with the power source. The pulse generator is also capable of generating an electric pulse. The light source is in electrical communication with the pulse generator in such a way that the light source turns on and off in response to the electric pulse received from the pulse generator. The guidewire includes a proximal end and a distal end. The optical fiber extends through the guidewire from the proximal end of the guidewire towards the distal end of the guidewire. The connector couples with the guidewire while allowing the light source to communicate with the optical fiber.

Abstract: Ablation apparatus such as a catheter (10) carrying an ultrasonic ablation device (20) including an ablation transducer (42) and a balloon reflector structure (22, 24) for directing ultrasonic energy from the ablation transducer into a ring-like ablation region (A) is provided with an imaging ultrasonic transducer (86) mounted on an imaging probe (80) which may be inserted into or through a passageway (18, 65) extending through the catheter and into or through the ablation device to image the ablation region or neighboring regions. Alternatively, the imaging transducer (102, 202) may be mounted within the balloon reflector structure or distal to this structure.

Abstract: Intravascular devices and systems include a flexible elongate member having a component configured to detect a physiological condition of a patient when the flexible elongate member is in a vasculature of the patient. The probe may also include a connector junction non-rotatably and permanently secured to the proximal portion of the flexible elongate member. The connector junction may be sized for grasping by a health care provider and for rotation to rotate the flexible elongate member when the flexible elongate member is in a vasculature of the patient. The connector junction may include a slack chamber to accommodate slack in a conductor that may be utilized when the flexible elongate member is introduced through tortious vasculature.

Abstract: A method of fabricating a pressure sensor is disclosed. Initially, a first metal is deposited on top of a substrate, and the first metal is patterned accordingly. A PVDF-TrFE nano fiber is then deposited on top of the first metal layer, and the PVDF-TrFE nano fiber is etched. A second metal layer is subsequently deposited on top of the PVDF-TrFE nano fiber, and the second metal layer is etched to form a pressure sensor.

Abstract: Embodiments of the invention relate generally to systems and methods for providing embolic protection to a medical procedure by filtration of debris generated by the medical procedure. The system and methods include an embolic protection device having an ultrasound transducer for assisting in intravascular navigation of the device.

Abstract: Disclosed are devices, systems, and methods for determining the dipole densities on heart walls. In particular, a triangularization of the heart wall is performed in which the dipole density of each of multiple regions correlate to the potential measured at various located within the associated chamber of the heart. To create a database of dipole densities, mapping information recorded by multiple electrodes located on one or more catheters and anatomical information is used. In addition, skin electrodes may be implemented. Additionally, one or more ultrasound elements are provided, such as on a clamp assembly or integral to a mapping electrode, to produce real time images of device components and surrounding structures.

Abstract: An image processing method enables an elasticity image of a body including a cavity to be produced on the basis of the material(s) forming the body, wherein the method includes the steps of: receiving a deformation image illustrating a field of movement of the points of the body on the basis of a pressure difference in the body, estimating a shape function of the body from the deformation image, calculating an elasticity image of the body on the basis of the shape function, of the pressure difference and of the deformation image.

Abstract: Deflectable apparatus and methods for performing a procedure within a patient's body using such apparatus are provided. Generally, the apparatus includes an elongate tubular member including a proximal end, a distal end, a longitudinal axis extending between the proximal and distal ends, a deflectable distal portion including first and second lumens spaced apart from one another on generally opposite sides of the longitudinal axis, and a handle coupled to the proximal end of the tubular member. A pull wire includes a loop disposed within the handle and first and second segments extending from the loop and slidably received in the first and second lumens, respectively, and coupled to the distal end. An actuator is provided on the handle for applying tension to either the first or the second segment to cause a distal portion of the tubular member to deflect, e.g., in opposite directions.

Abstract: An ultrasonic image display apparatus is provided. The ultrasonic image display apparatus includes an ultrasonic probe configured to move while in contact with a test object and configured to transmit and receive ultrasonic waves to and from the test object to obtain echo signals from a three-dimensional region of the test object, a parameter calculation section configured to calculate a parameter related to a moving velocity of the ultrasonic probe, a data generation section configured to generate data based on the echo signals of a plurality of frames, by selecting the frames in accordance with the parameter calculated by the parameter calculation section so that the echo signals of the frames used for generating the data are acquired within a required range, and a display section configured to display an ultrasonic image generated based on the data.

Abstract: A scanning type endoscope includes a light guide section configured to guide illumination light, a ferrule provided along the light guide section, an actuator configured to vibrate the ferrule to thereby swing a distal end of the light guide section, a cylindrical member configured to include a space containing the light guide section, the ferrule and the actuator and being provided along the light guide section, and a damping section configured to fix the ferrule to the cylindrical member and absorb vibration of the ferrule, in which the damping section is formed of a ferrule holding member configured to hold a proximal end of the ferrule and a ring-shaped member configured to fix the ferrule holding member to the cylindrical member, be disposed near a joint in the cylindrical member connected to holding member and be made of a material that absorbs vibration of the ferrule.

Abstract: A system (1010, 1110) for identifying a landmark is disclosed. The system includes a field generator (1016, 1116) for generating a magnetic field, an orthopedic implant (1030, 1130) located within the magnetic field, the implant having at least one landmark (1028, 1128), a removable probe (1029, 1129) with a first magnetic sensor (1026, 1126), a landmark identifier (1016, 1116) with a second magnetic sensor (1020, 1120) and a processor (1012, 1112) for comparing sensor data from the first and second sensor and using the set distance to calculate the position of the landmark identifier relative to the at least one landmark. The system allows for blind targeting of one or more landmarks.

Abstract: Disclosed are devices (100), systems (500), and methods for determining the dipole densities on heart walls. In particular, a triangularization of the heart wall is performed in which the dipole density of each of multiple regions correlate to the potential measured at various located within the associated chamber of the heart. To create a database of dipole densities, mapping information recorded by multiple electrodes (316) located on one or more catheters (310) and anatomical information is used. In addition, skin electrodes may be implemented. Additionally, one or more ultrasound elements (340) are provided, such as on a clamp assembly or integral to a mapping electrode, to produce real time images of device components and surrounding structures.

Abstract: The claimed method and system uses a hand-held based optical process to image large tissue volumes using a flexible probe head, increased data acquisition using multi-source illumination and multi-detector sensing, and tomographic reconstruction of sub-surface structures of a target object using ultrasonic tracking facilities.

Abstract: Ultrasound data is acquired by a synthetic aperture technique which uses multiple ultrasound transmissions from point sources. RF data is stored and processed. Doppler velocities for pixels in an insonified region are obtained by processing the stored data. One or more pan boxes may be provided. Doppler velocities may be determined by obtaining I and Q images for a plurality of frames and performing autocorrelation across the frames for some or all pixels in the frames.

Abstract: A delivery apparatus for introducing an intravascular filter into a body vessel of a patient includes a sheath defining a lumen, an intravascular filter positioned in the lumen, an ultrasound transducer positioned to the application side of the intravascular filter, a guide wire cannula and a tip located at an application side end of the delivery apparatus.

Abstract: An endoscope including an operation portion, an insertion portion pivotable relative to the operation portion, and a rotation knob to pivot the insertion portion about an axis of the insertion portion, includes: an insertion portion neutral position indicating portion, provided on an outer circumferential face of the rotation knob, configured to indicate a neutral position; and an indication ring, provided at the operation portion configured to include an operation portion neutral position indicating portion linearly aligned with the insertion portion neutral position indicating portion in an axis direction and indicating that the insertion portion is positioned at a neutral position, and two rotational angle indicating portions provided so as to be apart from the operation portion neutral position indicating portion in a circumferential direction, each of the two rotational angle indicating portions indicating rotation of the insertion portion.

Abstract: A US element includes a silicon substrate, wherein a lower electrode layer that has a plurality of lower electrode sections, and a plurality of lower wiring sections, and is connected to a lower electrode terminal to which a drive signal and a bias signal are applied, a lower insulating layer, an upper insulating layer in which a plurality of cavities are formed, an upper electrode layer that has a plurality of upper electrode sections and a plurality of upper wiring sections, and is connected to an upper electrode terminal at a ground potential for detecting a capacitance signal, and a protection layer are sequentially stacked on the silicon substrate, and the US element further includes a shield electrode section that is formed at least at an upper side of the lower wiring sections, and is connected to a shield electrode terminal at a ground potential.

Abstract: An imaging catheter assembly is presented. The imaging catheter assembly includes an imaging catheter which includes an imaging catheter tip. Further, the imaging catheter assembly includes a fluid reservoir connected to the imaging catheter and configured to deliver fluid through a proximal end of the imaging catheter tip. The imaging catheter assembly also includes a release mechanism configured to cause delivery of the fluid to the imaging catheter tip when activated.

Abstract: A patient positioning device has an electromagnetically transparent transfer plate for positioning an examination subject, and at least one patient bed. The electromagnetically transparent transfer plate can be disposed on the patient bed for imaging an examination region of the examination subject with a first imaging device. For imaging the examination region of the examination subject with the second imaging device that has an electromagnetic localization device, the electromagnetically transparent transfer plate is disposed above the electromagnetic localization device. An imaging system and a corresponding method for medical imaging make use of such a patient position device.

Abstract: Disclosed is a method of generating a diagnostic image by using a photoacoustic material. The method includes determining a wavelength band of light maximally absorbed by a photoacoustic material, based on at least one or more photoacoustic materials injected into an object, irradiating light, which corresponds to the determined wavelength band, onto an internal region of interest (ROI) of the object to acquire a photoacoustic signal corresponding to the irradiated light, generating a photoacoustic image indicating the ROI by using the photoacoustic signal, and combining and displaying the generated photoacoustic image and an image expressing that the light is being irradiated onto the ROI.

Abstract: A medical assembly for replacing a native heart valve of a patient. The medical assembly includes a radially expandable and collapsible prosthetic heart valve having a self-expandable stent body and a plurality of leaflet-forming membranes. The medical assembly also includes a deployment mechanism configured to deploy the prosthetic heart valve within the native heart valve of the patient. The deployment mechanism preferably includes a plurality of proximal deployment members coupled to a proximal end of the stent body. The deployment mechanism may also include a plurality of distal deployment members coupled to a distal end of the stent body. The prosthetic heart valve desirably includes a mechanical locking device configured to lock the prosthetic heart valve in a radially expanded configuration.

Abstract: A shaft being, e.g., flexible, that includes an elongated outer sheath, at least one drive shaft disposed within the outer sheath and a ring non-rotatably mounted on the at least one rotatable drive shaft and at least one light source mounted within the shaft, such that, upon rotation of the at least one rotatable drive shaft, the ring alternately blocks and allows light from the light source to be detected. The shaft may also include a moisture sensor disposed within the outer sheath of the shaft and configured to detect moisture within the outer sheath. The shaft may include couplings that connect a distal end of the outer sheath to a surgical attachment and a proximal end of the outer sheath to a remote power console.

Abstract: An apparatus for performing measurements in an artery includes a Doppler catheter, comprising a Doppler transducer and a wire connected to the Doppler transducer; and an elongated catheter body having a conduit therein for housing the wire of the Doppler catheter. The body has a proximal end and a distal end; wherein the wire is movable in the conduit relative to the catheter body so that the Doppler transducer and the wire are capable of being threaded into said conduit at the proximal end after the distal end of the catheter has been inserted into the artery, until the Doppler transducer emerges outside the conduit at the distal end of said body for performing ultrasound measurements in the artery. Another embodiment employs at least an additional side transducer for measuring the cross-sectional dimension of the artery useful for computing blood flow.

Abstract: Devices, systems, and methods for forward looking imaging are provided. A system for imaging a vessel of a patient comprises an elongated sheath having a proximal and a distal end. The sheath includes a flexible body with a first lumen in communication with a distal opening at the distal end. The system further comprises an imaging core disposed within the first lumen. The imaging core includes a transducer subassembly sized to extend within the first lumen. The transducer subassembly is adapted to transmit a beam, distally of the elongated sheath, through the distal opening.

Abstract: An ultrasonic probe includes a probe bend portion bending relative to a probe main body portion in a first bend direction and a second bend direction with a center of gravity being located on a first bend direction side with respect to a longitudinal axis. In the probe bend portion, a cross-sectional shape in a cross section perpendicular to a first perpendicular direction and a second perpendicular direction varies continuously along the first perpendicular direction and the second perpendicular direction with a cross-sectional center of gravity in the cross section perpendicular to the first perpendicular direction and the second perpendicular direction lying toward the second bend direction, as it is from the first perpendicular direction toward the second perpendicular direction.

Abstract: An image information obtaining apparatus having: a light source; a transducer which detects an acoustic wave and converts the acoustic wave to an electrical signal; a signal processing unit which generates image data, using the electrical signal; and a memory unit which stores a reference acoustic signal produced by the transducer detecting an acoustic wave generated when light is irradiated from the light source onto a phantom having acoustic parameters and optical parameters substantially the same as an object and converting the acoustic wave to an electrical signal, wherein the transducer produces an object acoustic signal by converting the acoustic wave, generated when light is irradiated onto an object from the light source, to an electrical signal; and the signal processing unit subtracts the reference acoustic signal from the object acoustic signal and generates image data from the signal resulting from this subtraction.

Abstract: A tunable ablation delivery device is disclosed. The tunable ablation delivery device includes a housing and a detection element on the housing for detecting a physiological indication. The tunable ablation delivery device further includes an ablation element disposed within the housing. An opening in the housing is positioned relative to the ablation element to facilitate a treatment using the ablation element modality.

Abstract: Needle deployment and imaging system includes a sheath, an imaging core, and interventional core. The imaging core and interventional core are received in first and second axial passages in the sheath and at least one of said cores will be removable and replaceable within the sheath. The imaging core may be extended from the sheath or be sealed within the first axial passage of the sheath. The interventional core will typically be advanced laterally or axially from a location near the distal end of the sheath.

Abstract: A system of catheter devices and methods for forming channels or passageways between a luminal anatomical structure (e.g., a blood vessel) and a target location (e.g., another blood vessel, an organ, a mass of tissue, etc.) for the purpose of rerouting blood flow or for delivering a substance or instrument, etc. to the target location.

Abstract: Collisions between a minimally invasive surgical instrument and patient tissue are prevented in various ways. In one aspect a body cavity is mapped by recording positions of a surgical instrument, and the map is used to insert another surgical instrument. In another aspect, a surgical instrument is inserted into a space vacated by a guide tube. In yet another aspect, a volume is defined in which a control system permits an instrument to move, and the volume is a sum of one volume that is defined by previous movements of the instrument and other volume that is defined by the boundaries of an image capture component. In yet another aspect, a real time image of a surgical site is mosaiced over a previously recorded more distal image of the site. Surgical instruments are visible in the real time image, and representations of the surgical instruments as they would appear in the previously recorded image are generated and displayed on the previously recorded image.

Abstract: In an ultrasonic probe including an element part 1 for transmitting and receiving ultrasonic waves, a relay cable 2 connected to the element part 1 and an oscillation mechanism part for oscillating the element part, a cross section of the relay cable 2, which is taken perpendicularly to a rotation axis 3 of the oscillation that is provided to the element part 1 by the oscillation mechanism part, has at least two arc-shaped parts smoothly connected each other, more specifically, S-shape arc-shaped parts or reversed S-shaped parts. In addition, the relay cable 2 is drawn from the surface of the element part 1 facing the rotation axis 3. In this manner, the stress applied to the relay cable 2 during the oscillation of the element part 1 can be dispersed, thereby improving durability of the relay cable 2.

Abstract: An apparatus for performing measurements in an artery includes a Doppler catheter, comprising a Doppler transducer and a wire connected to the Doppler transducer; and an elongated catheter body having a conduit therein for housing the wire of the Doppler catheter. The body has a proximal end and a distal end; wherein the wire is movable in the conduit relative to the catheter body so that the Doppler transducer and the wire are capable of being threaded into said conduit at the proximal end after the distal end of the catheter has been inserted into the artery, until the Doppler transducer emerges outside the conduit at the distal end of said body for performing ultrasound measurements in the artery. Another embodiment employs at least an additional side transducer for measuring the cross-sectional dimension of the artery useful for computing blood flow.