Abstract: System for measuring a characteristic of flow of liquid in a vessel of a patient comprising a transducer positioned in a vessel in a patient for supplying ultrasonic energy. The transducer produces a substantially uniform beam which encompasses the vessel. The transducer receives ultrasonic energy back scattered from the red blood cells and provides an electrical output signal. A first moment detector is provided which receives the electrical output from the transducer and provides a first moment signal. Normalization is provided to the output of the first moment detector to provide an electrical output representing a characteristic of the flow of the liquid in the vessel.

Abstract: 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.

Abstract: Device for measuring volumetric blood flow in a vessel comprising a catheter having proximal and distal extremities. A balloon is carried by the distal extremity of the catheter. A balloon inflation lumen is carried by the catheter and is in communication with the balloon. A toroidal ultrasonic transducer is carried by the catheter and is spaced proximally of the balloon. Electrical circuitry is provided for supplying electrical energy to the transducer. The transducer produces a large substantially uniform beam of ultrasonic energy to illuminate a vessel of approximately three centimeters in diameter with the ultrasonic energy.

Abstract: An ultrasonic scanner for medical diagnostics is disclosed. The scanner includes an upper head assembly and a lower drive assembly. The upper head assembly includes a fluid chamber filled with a liquid acoustic couplant. An oscillating transducer is driven in an asymmetric motion by a linkage coupled off-center to a flywheel within the fluid chamber. An inflatable bladder is provided in the upper assembly which is in fluid communication with the fluid chamber. The application of force to the membrane boot of the scanner forces fluid into the bladder. Once the external pressure is removed, the bladder is biased such that it is compressed, thereby forcing fluid to return to the fluid chamber and maintaining a generally constant pressure within the chamber. Supporting electronics are provided including means for compensating for the asymmetric motion of the transducer.

Abstract: An ultrasound imaging apparatus is described. The hand-held device includes a first oscillating transducer for providing a B-scan display and an offset second transducer which is manually positioned for providing Doppler data. The transducer pulses are interlaced and Doppler transmissions are inhibited to permit B-scan transmissions. However, circuits provide a continuous signal representing a Doppler signal when the Doppler transmissions are inhibited.

Abstract: The invention involves a digital synthetic-focus, acoustic imaging system which is operative in real time and includes one or more electro-acoustic transducers arranged to receive broadband pulses from a pulse generator for excitation of acoustic pulses which are directed into the region under observation. Signals reflected from an object or discontinuity in the region are received by the same transducers, and after inverse filtering and nonlinear amplification are converted to digital signals. These digital signals are stored in separate high speed random access memory units for storage, but are subsequently time-equalized through use of a programmed focus memory unit prior to delivery to a digital adder and thence through a digital-to-analog converter for ultimate intensity modulation on a raster scanned display unit which provides the real time image.