Abstract: In an ultrasonic endoscope, a plurality of flexible substrates (43) are connected to an ultrasonic probe (4) as a signal transmission member for transmitting a signal which is inputted into/outputted from the ultrasonic probe (4). The plurality of flexible substrates (43) are drawn into a curved portion (2) and connected to a signal cable (47) at lengthwise different positions respectively in the inside of a flexible tube portion (1).

Abstract: In a radial scan, forward viewing ultrasonic endoscope, centering mating portions (46, 32) that permit the outer surface (45) of ultrasonic probe (4) and the outer surface (31) of tip body (3) to meet flush with each other at the boundary are formed in ultrasonic probe (4) and in tip body (3) and the gap between the inner peripheral surface (41a) of ultrasonic probe (4) and mating surface of the front half (33) of tip body (3) is formed to be larger than the gap between centering mating portions (46, 32).

Abstract: The invention relates to a resonance based pressure transducer system, insertable into a living body for the in vivo measurement of pressure. It comprises a pressure sensor (2) having a mechanical resonator (16), the resonance frequency of which is pressure dependent; and a source of ultrasonic energy (4). The sensor (2) is mechanically coupled to said source (4) of ultrasonic energy, and the sensor and the source of ultrasonic energy are provided on a common, elongated member (6) at the distal end thereof. A system for pressure measurement comprises an AC power supply, a resonance based pressure transducer system, and a control unit for controlling the supply mode of the AC power, and for analyzing a resonance signal emitted from the resonance based pressure transducer system.

Abstract: A guide wire for medical treatment has a flexible main wire and a coil spring in which the main wire is inserted. The coil spring has an untransmissive part and a transmissive part and is manufactured by welding together under a proper welding load a wire made of a material through which radiation cannot pass and a wire made of a material through which radiation can pass to form a base wire, which is coiled to form the coil spring. The guide wire can be smoothly curved and smoothly inserted or extracted into or from the blood vessel without injuring the blood vessel.

Abstract: The ultrasound probe cover includes a conventional condom which is adapted to fit over an ultrasound probe. The cover is secured to the probe in a water-tight arrangement at the proximal end of the cover by an elastic band. An elongated hollow tube is secured to the inner surface of the cover, which tends to result in an equalization of fluid pressure at both ends of the condom cover during insertion and retraction of the condom into and out of a bodily opening, such as the rectum, of a patient.

Abstract: Sound energy of a proximally arranged sound source 30 and laser radiation of a therapeutic laser 17 are simultaneously transmitted with an endoscopic instrument via flexible waveguides 3 into the body interior. The sound energy is in a power and frequency range adequate for the cutting tissue 16 and the therapeutic laser 7 operates preferably in the near infrared. The waveguides are quartz glass fibers 3 which can transmit sound energy as well as also light energy.

Abstract: A motor control apparatus (1) for articulating a probe (3) is constructed with a reversible motor (10) and at least one tension adjusting cable (4) to articulate the probe (3).

Abstract: An ultrasonic imaging catheter comprises a catheter body having a distal region and proximal region. The distal region has a reduced cross-sectional area compared to that of the proximal region, and the proximal region includes at least two lumens therethrough for accommodating a movable guidewire and a rotatable working element, respectively. The catheter body may be inserted over the moveable guidewire, with the guidewire passing through a lumen in the distal region and the guidewire lumen in the proximal region. After positioning the catheter body, the guidewire can be retracted from the distal region and into the proximal region, leaving the lumen in the distal region available for the rotatable working element. Such a construction allows over-the-wire imaging of the catheter while minimizing the width of the catheter in the distal region which remains available for placement of the working element.

Abstract: A device for use in placing a non-sterile sensor probe (70, 154, 180, 206, 208) such as an ultrasound scanning transducer in a desired position within a patient's body (12), with a probe-receiving tube (36, 92, 143, 139, 152, 201, 203, 205) having a closed distal end (38, 95, 212, 220, 222) so that a probe inserted within the tube through an open proximal end (49, 97) located outside the patient's body is isolated from contact with or contamination of the interior of the patient's body. The probe-receiving tube is attached to and extends alongside an elongate support member (18, 82, 130, 134, 138, 142, 200, 202, 204) which aids in placement of the probe-receiving tube in a location proximate an organ to be observed by use of a sensor probe in the probe-receiving tube. The elongate support member may be a chest drain tube.

Abstract: The present invention is a device localization system that uses one or more ultrasound reference catheters to establish a fixed three-dimensional coordinate system within a patient's heart using principles of triangulation. The coordinate system is represented graphically in three-dimensions on a video monitor and aids the clinician in guiding other medical devices, which are provided with ultrasound transducers, through the body to locations at which they are needed to perform clinical procedures. In one embodiment of a system according to the present invention, the system is used in the heart to help the physician guide mapping catheters for measuring electrical activity, and ablation catheters for ablating selected regions of cardiac tissue, to desired locations within the heart.

Abstract: An ultrasonic endoscopic probe is provided with an articulating distal tip at which and ultrasonic transducer is located. The articulating section of the probe can be locked in an articulated position by a lock control located at a control section of the probe. The locking force is variably selectable by the user, so that the articulating section will be locked in position by a desired force. The articulating section is controlled by cables, which include cable tension adjustments that also serve to delimit the range of articulation. The articulating section is formed of alternating pivot rings with intervening polymeric pivot beads, which provide repetitively smooth articulation. The ultrasonic transducer is rotatable to steer the acoustic scan plane during use, and a sliding membrane between the transducer and its acoustic window allows the transducer to rotate smoothly without sticking.

Abstract: A sector scanning, intracavitary ultrasonic probe has an ultrasonic oscillator array (20) provided at the tip (12) of a cavity insertion portion (11) for scanning a sectorial area lateral to the tip (12). Individual ultrasonic oscillators (21) of the array (20) are inclined to be perpendicular to respective radial lines converging to a point located opposite from the sectorial area with respect to the ultrasonic oscillators, and are aligned straight in equidistant positions from the longitudinal axis of the tip (12) of the insertion portion (11).

Abstract: An angioplasty guidewire includes a proximal shaft formed with an axial passage and a variable stiffness intermediate section extending axially from the tubular shaft and having a corridor aligned axially with the passage and terminating at a distal joint. The intermediate section comprises a plurality of stiffening elements. A core element is slidably disposed axially through the passage and includes a distal end projecting into the corridor and attached to the distal joint while a flexible distal tip is mounted to the end of the intermediate portion and projects axially therefrom.

Abstract: An invasive probe for mapping the walls of a lumen employs a real-time tracking means and a wall distance measurement means. As the probe is advanced within the lumen, the real-time tracking means provides three-dimensional coordinates of the probe's position and orientation. Concurrent with probe localization, the distance between the probe and the lumen walls is measured. Both the probe position and the wall distance measurement are sent to a data acquisition system which in turn provides a graphic or numeric display to the operator. Probe tracking can be performed with radio-frequency, magnetic resonance, ultrasonic techniques or the like. If desired, lumen wall distance measurements can be performed with magnetic resonance or ultrasound methods. Lumen wall distance measurements can also be performed with mechanical devices such as balloons and/or expanding structures.

Abstract: An ultrasonic transducer assembly includes a transducer mounted in a housing, the transducer including a piezoelectric element and respective matching and backing layers formed on the opposite sides thereof, the transducer mounted in the housing encapsulated with a non-conductive potting material. A portion of the matching layer is removed, e.g., by etching, to expose a portion of an underlying electrode formed between the piezoelectric element and the matching layer. A portion of the non-conductive potting material between the etched portion of the matching layer and a signal wire disposed in the housing is also removed. The respective voided portions of the matching layer and non-conductive potting material are filled with an electrically conductive matching material to electrically couple the electrode, and, thus, the piezoelectric element, to the signal wire.

Abstract: An apparatus is described for treating arterial occlusions combining an intraluminally operable catheter, having an occlusion-crossing working element, with a micro-invasive extraluminally operable locator for imaging the progress of the working element through the occlusion. Conical, abrasive, blunt-dissecting, and sharp-pointed, and steering and non-steering working elements including guide wires are described. Acoustic transducers and a flexible imaging tube are described for the locator. A suction cup is described for removably anchoring the imaging tube to a surface. A signal-emitting working element and cooperating signal-receiving locator are described. A method for treating arterial occlusions is described.

Abstract: An ultrasound endoscope having an endoscopic observation system along with an ultrasound scan system. An outlet opening of an instrument passage, which is shunted from a biopsy channel of the endoscope, is located within a view field of an endoscopic image pickup window, which largely overlaps a scan range of the ultrasound scan system. A puncture instrument having a sharp-pointed rigid needle at the instrument outlet opening, which is in the view field of the endoscopic image pickup, can be monitored by way of the endoscopic observation system to check its position for safety purposes, from a slightly projected position to a largely projected position whenever it spontaneously gets out of the instrument outlet opening. Once the puncture needle is driven into an intracavitary wall toward a diseased portion in target, it can be monitored through the ultrasound scan system.

Abstract: An angioplasty guidewire includes a proximal shaft and an intermediate section extending from the shaft to a distal joint and having a stiffener and a flexible member. The stiffener and the flexible member are disposed in coaxial slidable relationship and operable, as the stiffener and flexible member undergo relative axial shifting, to cooperatively impart a variable stiffening force on the intermediate section. A flexible distal tip mounts to the end of the intermediate section and projects axially therefrom.

Abstract: A surgical instrument comprising a probe for insertion into the body of a host and for manipulating the tissues of the host, the probe including an ultrasound transducer element for locating and positioning the probe within the body of the host; and a method for manipulating the tissues of a host using the surgical instrument.

Abstract: A device for use in placing a non-sterile sensor probe such as an ultrasound scanning transducer in a desired position within a patient's body, with a probe-receiving tube having a closed distal end so that a probe inserted within the tube through an open proximal end located outside the patient's body is isolated from contact with or contamination of the interior of the patient's body. The probe-receiving tube is attached to and extends alongside an elongate support member which aids in placement of the probe-receiving tube in a location proximate an organ to be observed by use of a sensor probe in the probe-receiving tube. The elongate support tube may be a chest drain tube.

Abstract: A probe having the ability to deliver cardioplegia solution to the coronary sinus under direct visualization and to provide venous drainage from the right atrium for cardiopulmonary bypass. The probe has an elongate tubular member, including a distal end, a proximal end, and a lumen. A membrane, optionally perforated, mounted within the lumen of the tubular member partitions the lumen and is removable or penetrable by a cardioplegia catheter. The distal end comprises a toroidal balloon or a circumferential recessed vacuum manifold. A vacuum port communicates with the distal end of the tubular member or the vacuum manifold. Methods of using the cardioplegia access view probe for catheterization of the coronary sinus and for venous return as herein described are also disclosed.

Abstract: A needle guidance attachment device for an endoluminal ultrasound probe that allows removal of the probe while the needle is in position in the tissue. The device includes an elongated needle carrier having a longitudinal slot with a transverse opening. The carrier includes a pair of retaining bands adapted to fit around a cylindrical-shaped ultrasound transducer and to orient the needle carrier along the longitudinal axis of the probe. An elongated cover is slidably coupled to the carrier in a longitudinal orientation such that at least a portion of the slot is covered in a first, closed position and uncovered in a second, opened position. The cover moves between its open and closed position axially about the longitudinal axis of the needle carrier.

Abstract: A flexible, elongate probe having a distal end for insertion through physiological tissue, preferably through a lumen in the tissue. The probe includes a sensor, which generates signals indicative of a characteristic of the tissue in a vicinity of the probe, and an alignment mechanism, which deflects the distal end of the probe in response to the signals. The signals may be indicative of obstructions or of the direction of a clear channel in the lumen. The sensor preferably comprises one or more ultrasound transducers.

Abstract: An intravascular imaging guidewire which can accomplish longitudinal translation of an imaging plane allowing imaging of an axial length of a region of interest without moving the guidewire. The imaging guidewire comprises a body in the form of a flexible elongate tubular member. An elongate flexible imaging core is slidably received within the body. The imaging core includes a shaft having an imaging device mounted on its distal end. The body and the imaging core are cooperatively constructed to enable axial translation of the imaging core and imaging device relative to the body. The body has a transparent distal portion extending an axial length over which axially translatable imaging may be performed. The imaging guidewire has a maximum diameter over its entire length sized to be received within a guidewire lumen of an intravascular catheter.

Abstract: A coupling adaptor for electrically and rotationally coupling a tail end connector of an endoscopically inserting ultrasound probe with a connector portion of a separate probe control unit. The coupling adaptor is intended for use with an endoscopically inserting ultrasound probe having a bulky ultrasound scanner assembly at the nose end of a flexible cord, and a thin and narrow tail end connector at the proximal end of the flexible cord for passage through a biopsy channel of an endoscope. The coupling adaptor is provided with, within a stationary housing, a pair of rotationally interconnected front and rear rotary members to be disconnectibly coupled with the tail end connector of the ultrasound probe and a rotational drive means on the probe control unit, respectively.

Abstract: Implantable apparatus for measuring a fluid flow in the body of a subject, including a stent, having a generally cylindrical radial outer wall and a central lumen. A flow parameter sensor is fixed to the stent, and measures a parameter relating to a rate of blood flow through the stent. A transmitter transmits signals responsive to the measured parameter to a receiver outside the body.

Abstract: An ultrasound transducer assembly of the present invention includes a flexible circuit to which an ultrasound transducer array and integrated circuitry are attached during fabrication of the ultrasound transducer assembly. Integrated circuitry and transducer elements are attached to the flexible circuit while the flexible circuit is in a substantially flat shape. The contacts of the transducer elements are positioned on substantially the same plane such that electrical contact with signal and ground lines on the flexible circuit is established without the need for conductive bridges to physically remote electrodes. In an embodiment of the invention wherein the transducer elements are arranged in a cylindrical array, gaps are entirely filled with backing material having a relatively low acoustic impedance. Structure integrity is enhanced and a path to ground facilitated by electrically conductive disks attached to the ends of the transducer assembly.

Abstract: An ultrasound probe coupler for electrically and rotationally coupling an ultrasound probe with a probe control unit of an ultrasound examination system. The probe coupler essentially includes a tail end connector provided at the tail end of a flexible cord to be connected to the probe control unit. The tail end connector is provided with a stationary ring which is fixedly connected to a tail end portion of the flexible cord, and a rotational coupler having a series of rotary rings, including at least one electrode ring, for coupling the flexible shaft with a rotational drive means and an electrode on the part of the probe control unit. The rotational coupler further includes a rotation transmission member detachably connected to one of the rotating electrode rings and projected radially outward of the inner periphery of the stationary ring for engagement with a rotational drive member on the part of the probe control unit.

Abstract: An ultrasound probe of the present invention comprises a rod-like grip section constituting a rear section of the probe, a rod-like insertion section constituting a forward section of the probe and having a piezoelectric element array at a forward end and a slot structure formed parallel to an axis of the grip section. A centesis instrument is put on the slot. This specific arrangement allows the axis of the centesis instrument to be less displaced relative to the axis of the probe, so that the centesis instrument is not unsteady relative to the probe. Further, the centesis instrument ensures readier attachment and detachment to and from the probe simply by putting a body of the instrument on the probe.

Abstract: Ultrasonic imaging method and apparatus in which a reference waveform which is substantially free of echoes is modified to be equal to a weighted sum of the reference waveform and filtered signals from the transducing elements which transmit the ultrasonic waves and receive the reflected echoes. The modified waveform is then subtracted from the transducer signals to remove ringdown signals and provide a displayed image which is substantially free of ringdown artifacts.

Abstract: In one embodiment, an ultrasound imaging assembly (80) includes a housing (82) having a longitudinal axis (88), a proximal end (86), and a distal ending (84) defining a receptacle (90). The imaging assembly includes a transducer package (60) having a central axis (62) and an imaging surface (66) positioned at a desired angle (106) relative to the central axis. The transducer package is at least partially disposed within the receptacle so that the central axis is generally perpendicular to the longitudinal axis. Such a configuration permits a relatively large percentage of the ultrasound signal to pass through a sheath (120) surrounding the imaging assembly and reduces assembly-to-assembly variations.

Abstract: A catheter for imaging a cavity. The catheter includes a sheath having a distal end that is introduced into a cavity to be imaged and a proximal end that resides outside of the cavity. The sheath includes a tubular member with a first fixed probe located proximate to the distal end and fixed in relation to the tubular member while the cavity is being imaged. The catheter also includes a transducer for delivering an energy pulse in a predetermined direction relative to the transducer and collecting echoes generated by the pulse. The transducer is located within the sheath proximate to the distal end of the sheath and includes a transducer probe affixed to the transducer. A drive cable in the catheter causes the transducer and the transducer probe to rotate relative to the sheath. The drive cable connects the transducer to a mechanical drive mechanism located at the proximate end of the sheath.

Abstract: An ultrasound probe of the type having, successively from its head to tail end, an ultrasound scanner head assembly accommodating an ultrasound transducer element rotatably within an end cap, an elongated flexible cord having a flexible transmission shaft of tightly wound metal wire coils within an outer sheathing tube, and a tail end connector.

Abstract: The present invention provides for catheter systems and methods of their use. In one embodiment, the invention provides a catheter comprising a catheter body having a proximal end, a distal end and a working lumen. A drive cable is disposed within the lumen and at least one transducer is attached to the cable near the distal end. A rotary transformer is included, comprising a transformer stator which is spaced apart from a transformer rotor. The rotor is operably attached to the cable to rotate therewith. The rotor is electrically coupled to the transducer and is magnetically coupled to the stator to allow a signal to be transmitted from the transducer to the stator during rotation of the cable.

Abstract: An ultrasound transmission medium feed device particularly for an endoscopically inserting ultrasound probe adapted to be introduced into a body cavity through and under the guidance of one of biopsy channels provided on an endoscope.

Abstract: An ultrasonic diagnostic device of which forms two scanning planes includes an ultrasonic search unit at the tip of a long insertion part which conducts radial scanning by emitting ultrasonic waves in a direction vertical to the longitudinal axis direction of the insertion part, a reflector provided along with the ultrasonic search unit which reflects a part of the ultrasonic waves emitted from the ultrasonic search unit to the anterior direction of the insertion part, and a tip cap which covers the ultrasonic search unit and the reflector and is made of a material permeable to the ultrasonic waves emitted from the ultrasonic search unit.

Abstract: An ultrasonic imaging catheter comprises a catheter body having a distal region and proximal region. The distal region has a reduced cross-sectional area compared to that of the proximal region, and the proximal region includes at least two lumens therethrough for accommodating a movable guidewire and a rotatable working element, respectively. The catheter body may be inserted over the moveable guidewire, with the guidewire passing through a lumen in the distal region and the guidewire lumen in the proximal region. After positioning the catheter body, the guidewire can be retracted from the distal region and into the proximal region, leaving the lumen in the distal region available for the rotatable working element. Such a construction allows over-the-wire imaging of the catheter while minimizing the width of the catheter in the distal region which remains available for placement of the working element.

Abstract: A stopper mechanism for an endoscopically insertable ultrasound probe which is designed to be introduced into a body cavity through a biopsy channel provided internally of an insertion instrument of an endoscope and which is of the type having a bulky ultrasound scanner head at the distal end of an elongated thin flexible cord and being placed in the endoscopic biopsy channel except the bulky scanner head when in use. A stopper protuberance is projected radially outward from a connecting neck portion of the ultrasound probe immediately on the proximal side of the scanner head where the flexible cord of the ultrasound probe is connected to a connecting member axially extended from the ultrasound scanner head.

Abstract: A parameter indicative of the status of fluid flow is remotely monitored in a vessel, a natural graft, or a synthetic graft. One or more transducers are provided either in a wall of a synthetic graft or adjacent to a vessel or natural graft to monitor the parameter. A conformal array transducer or a tilted element is used to monitor fluid flow or velocity through the graft or vessel based on the effect of the fluid on ultrasonic waves produced by the transducers. The conformal array transducer comprises a plurality of elements that curve around the graft or vessel and are excited with an input signal provided by an implantable electronics circuit, producing ultrasonic waves that propagate into the fluid flowing within the graft or vessel. Transit time or Doppler measurements are made using an appropriate number of these transducer to determine either fluid flow or velocity.

Abstract: A surgical implement, such as a surgical electrode, and an ultrasound transducer, both extend through a single elongated insertion member, typically, a catheter. The ultrasound transducer extends from the proximal region of the surgical instrument containing the instrument controls toward the distal end of the catheter from which at least the operative tip of the surgical implement and the ultrasound transducer extend. In one embodiment, the catheter also contains a fiber-optic endoscope, thus allowing visual as well as ultrasound monitoring of the surgical site, before, during and after conduct of the surgical procedures. Means are provided for rotation of the ultrasound transducer to enable generation of a circular tissue reflectivity image transverse to the axis of the ultrasound transducer. Means are also provided for selective longitudinal movement of all elements contained within the catheter.

Abstract: A steering mechanism for an ultrasonic transducer assembly includes a housing having a longitudinal axis that extends generally parallel to the proximal end of a catheter. An annular steering ring is mounted to the housing for rotation about the longitudinal axis, and a steering hub is mounted for rotation in the housing and coupled to the steering ring such that rotation of the steering ring with respect to the housing causes rotation of the steering hub. A steering line is secured adjacent the steering hub and extends to the distal end of the catheter such that rotation of the steering hub alters the effective length of the steering line to steer the distal end. The steering line is preferably formed of a stranded polymer such as a gel spun polyethylene.

Abstract: A probe head joint construction for an endoscopically ultrasound probe to be introduced into a body cavity through a biopsy channel provided internally of an endoscopic insertion instrument, the ultrasound probe having a bulky ultrasound scanner head at the distal end of an elongated thin flexible cord having a cable sheathed in a soft flexible outer tube for placement in said endoscopic biopsy channel, and the ultrasound scanner head having an ultrasound transducer element housed in an end cap of a larger diameter than the endoscopic biopsy channel.

Abstract: The present invention is a method and apparatus for ultrasound imaging of internal structures near a stomach of a patient. Under the present invention, high resolution images of abdominal structures may be obtained including, for example, the abdominal aorta, kidneys, the liver, superior mesenteric, both renal arteries, the hepatic arteries, the splenic artery, the vena cava, renal veins, portal vein, splenic and mesenteric veins. High resolution imaging of blood flow within blood vessels including those within organs may also be obtained. High-resolution imaging of these structures thereby obviates the need for otherwise invasive procedures. The imaging device of the present invention includes a probe having a head, a body and an end opposite the head. An ultrasonic transducer is coupled to the head of the probe and a gel material covers the ultrasonic transducer to enable a good contact with a stomach wall portion.

Abstract: A needle guide mount has a main guide body, with a knob arm and a pivot arm each attached at one end to the main guide body. A gate assembly is pivotably in the pivot arm and has an open position, in which the gate assembly can pivot freely away from the knob arm, and a closed position, in which the gate assembly is secured in the knob arm. The gate assembly preferably has a shaft, a knob that can move longitudinally and rotatably on the shaft, and a locking arrangement that permits the gate assembly to enter the closed position only when the central axis of the gate assembly lies less than a predetermined maximum misalignment angle away from a correct mounting alignment axis. If the guide mount is not properly positioned on the probe, then the gate assembly is out of correct alignment and the locking arrangement is unable to engage. The operator can then easily feel that she is not able to mount the guide.

Abstract: An ultrasound mixed signal multiplexer/pre-amplifier application specific integrated circuit (ASIC) for supplying voltages to a group of elements of an ultrasound array, receiving voltages from the same or another group of elements of the array, and amplifying the received voltages for transmission to external circuitry. The transmit groups and receive groups are shifted to provide accurate visual images with a minimal number of transmit and receive cycles.

Abstract: Methods and apparatus for non-uniform rotation distortion detection for enhanced intravascular ultrasound imaging. The present invention provides methods and apparatus which detect non-uniform rotation in an improved manner without using beacons which may create shadowing of tissue behind the beacons or other undesired artifacts in the image. In specific embodiments, the present invention may provide a particularly simple and useful solution for addressing the problem of non-uniform rotation distortion in intravascular ultrasound imaging in systems which use mechanical scanning. In specific embodiments, the present invention utilizes correlation of received signals in an image vector from reverberating ultrasound in a bubbly liquid-flushed catheter to determine non-uniform rotation of the transducer within the catheter.

Abstract: A medical device for insertion into human body having an echogenic portion of enhanced visibility in an ultrasound scan. The echogenic portion includes an echogenic material comprising a plastic impregnated with sonically reflective particles, the particles having an average size of less than 500 nanometers and formed of a substance having a specific gravity of 5 or greater. Preferably the particles have an average size of less than 100 nanometers and the sonically reflective particles are 5% to 40% of the echogenic material.

Abstract: An ultrasound imaging apparatus for measuring the curvature of a vessel consisting of a distal transducer mounted on a transducer supporting device. A resilient deformable material is attached to the transducer supporting device and allows the angular orientation of the transducer to change based on the local vessel curvature. The ultrasound imaging apparatus emits ultrasound radiation from multiple pulsed electronic signals as the apparatus is moved through a vessel or sheath catheter at a known velocity. The distal transducer receives the scattered ultrasound radiation and differences in the phase shifts of the scattered ultrasound radiation are analyzed to detect or measure curvature.

Abstract: A guide wire assembly comprises a tubular body having a distal end and an proximal end. At least a portion of the body comprises a single continuous helical spring to which one or more tubular electrodes are secured. The electrodes are insulated from the spring by means of an insulator. The electrodes can take a variety of forms, including conductive ribbons, longitudinally split conductive tubes, tubular sections, etc. The guide wire assembly may further include a variety of sensors, such as velocity sensors or temperature sensors. In order to allow flowable material to be passed to the distal end of the guide wire, the guide wire can include a catheter tube passable over the tubular body of the guide wire.

Abstract: Apparatus and method are described for introducing an imaging catheter to the coronary vasculature. A guiding catheter is introduced so that the distal end of the guiding catheter engages a coronary os. The distal end of the guiding catheter is shaped so that a mark on the distal end is oriented in a predetermined orientation relative to the coronary vasculature. An imaging catheter is then introduced through the guiding catheter and an image of the mark is produced with the imaging catheter while in the guiding catheter. In this manner, the relative orientation of the produced image and the coronary vasculature is known.