Cardiometrics, Inc.

Pharmasonics, Inc.

General Electric Company

Menahem F Nassi

Paul Douglas Corl

Mark W Cowan

Jeffrey J Christian

Jeffrey S Frisbie

Axel F Brisken

Ronald G Williams

Robert F Zuk

John R McKenzie

Jerome Segal

Ilan Lifshitz

James P Stonestrom

Stanley Levy, Jr

A method of treating a target region in a body lumen, said method comprising: directing a uniform dose of ultrasonic energy from an interior of the lumen radially outward over a treatment length of the lumen, wherein the dosage of ultrasonic energy received at any one point along the length varies by no more than plus or minus 6 decibels from that received at any other point along the length.

Therapeutic ultrasound catheter for delivering a uniform energy dose

Therapeutic ultrasonic catheter for delivering a uniform energy dose

Vascular catheter for measuring flow characteristics of a liquid in a vessel having a wall and an axis extending longitudinally of the vessel parallel to the vessel wall comprising a flexible elongate tubular member adapted to be introduced into the vessel and having proximal and distal extremities. The flexible elongate member has a lumen extending therethrough. The flexible elongate member has at least one preformed bend thereon adjacent the distal extremity. A plurality of ultrasonic transducers are mounted on the flexible elongate member adjacent to the bend. Conductors are connected to the ultrasonic transducers and extend through the proximal extremity of the flexible elongate tubular member. The flexible elongate member has an opening therein in the distal extremity which is a communication with the lumen.

Vascular catheter for measuring flow characteristics and method

A doppler guide wire having an inflatable balloon thereon which is inflatable with a balloon inflation medium. An elongate flexible member having proximal and distal extremities. An ultrasonic transducer is secured to the distal extremity of the elongate flexible member. An inflatable balloon mounted on the distal extremity of the elongate flexible member proximal of the ultrasonic transducer. A balloon inflation lumen opens into the interior of the balloon and extends along the length of the elongate flexible member. Conductors are connected to the ultrasonic transducer and extend along the length of the elongate flexible member.

Doppler elongate flexible member having an inflatable balloon mounted

Method for providing micro-miniature high efficiency ultrasonic transducer assembly having a diameter of 0.018 inches or less. A transducer is formed from a selected transducer material to provide a cylindrical transducer having front and back sides with a thickness which is one-half of the diameter of the transducer +/-5%. The frequency constant of the material is ascertained. The frequency of operation of the transducer is ascertained by dividing the frequency constant by the thickness of the transducer in mils. The transducer is mounted in a housing and leads are secured to the front and back sides of the transducer.

Method for providing a miniature ultrasound high efficiency transducer

Apparatus for measuring the volumetric flow of a liquid in a vessel having a wall and having an axis extending longitudinally of the vessel parallel to the vessel wall. A flexible catheter is provided which has a longitudinal axis adapted to be disposed in the vessel. The catheter has front and back sides. First, second, third and fourth transducers are carried by the catheter. The first, second and fourth transducers are disposed on the front side of the catheter and the third transducer is positioned on the back side of the catheter. The second and fourth transducers are spaced apart a predetermined distance. The first, second and third transducers comprise a first set of transducers and the first, third and fourth transducers comprise a second set of transducers. Instrumentation is connected to the first, second, third and fourth transducers. The instrumentation causes the first, second, third and fourth transducers to emit ultrasonic energy beams therefrom. The first transducer is positioned on the catheter to emit an ultrasonic energy beam at an angle with respect to the longitudinal axis of the catheter. The second and third transducers are positioned in the catheter to emit ultrasonic beams extending generally perpendicular to the longitudinal axis of the catheter. The fourth transducer is positioned so that it emits an ultrasonic beam. The instrumentation receives the signals from the first, second, third and fourth transducers and measures the velocity of profile of the flow of liquid in the vessel by Doppler shift and ascertains the diameter of the vessel in the vicinity of the transducers. The instrumentation is capable of ascertaining which of said first and second sets of transducers provides more accurate velocity profile and diameter measurements of the vessel.

Position in dependent volumetric flow measuring apparatus

Apparatus for measuring volumetric flow of a liquid in a vessel having a wall and having an axis extending longitudinally of the vessel parallel to the vessel wall. A flexible catheter is adapted to be disposed in the vessel. First and second ultrasonic transducers are carried by the catheter on one side of the catheter and face the wall of the vessel so that the beams from the transducers each cross substantially the longitudinal axis of the vessel. The first transducer beam is inclined at an angle with respect to the longitudinal axis of the vessel. The second transducer beam is inclined in a direction which is generally perpendicular to the longitudinal axis of the vessel.

Apparatus and method for continuously measuring volumetric blood flow

Guidewire comprising a flexible elongate member having a distal extremity with an ultrasonic transducer secured to the distal extremity of the flexible elongate member. The transducer has a diameter ranging from 0.007 inches to 0.018 inches and has a thickness and a diameter to provide a transducer having an aspect ratio with a thickness which is one-half of the diameter .+-.5%. Electrical leads are connected to the transducer and extend the length of the flexible elongate member.

Miniature ultrasound high efficiency transducer assembly, guidewire

A guide wire assembly comprising a flexible guide wire having a diameter of 0.018 inches or less and having a connector assembly. The connector assembly includes male and female connectors. The male connector includes a conductive coil spring and a core wire which extends beyond the conductive coil. The female connector includes a recess for receiving the core wire as well as a conductive element for engaging the coil spring.

Guide wire assembly with electrical functions and male and female

An improvement is disclosed which is applicable to the method for constructing a two-dimensional representation of an object slice lying in a quasi-plane by positioning a radiation source providing a fan beam incident on the object, positioning detector means opposite the source and aligned therewith and lying in said quasi-plane for detecting radiation in said quasi-plane not absorbed or scattered by the object; effecting relative rotation between the object and the source-detector combination about an axis of rotation such that the source and detector means remain in the quasi-plane; effecting measuring projections from the source at a plurality of angular positions during the rotation to obtain a multiplicity of measured data readings from the detectors at each said projection; and reconstructing a two-dimensional representation of the object slice by convolving the data without reordering same, and scaling and back projecting same. Pursuant to the improvement, estimated detector data is generated at desired additional projection angles, by reflecting the measured detector data obtained during the said measuring projections, and the reconstruction step is performed utilizing both the measured and the estimated detector data.

Growing community of inventors

Palo Alto, CA, United States of America

Menahem F Nassi