ULTRASONIC ECHO ENCEPHALOGRAPH FOR MEASURING THE POSITION OF THE MIDLINE

• US 3,713,329 A
• Filed: 01/04/1966
• Issued: 01/30/1973
• Est. Priority Date: 03/16/1965
• Status: Expired due to Term

• Current Assignee: Staveley Instruments Incorporated
• Original Assignee: Donald W. Munger
• Inventors: Munger, Donald W.
• Primary Examiner(s): Queisser, Richard C.
• Assistant Examiner(s): Beauchamp, Jr., John P.
• Application Number:
  US04/518,575
• Time in Patent Office: 2,583 Days
• Field of Search: 73/67.5-67.9 128/2V
• US Class Current: 600/451
• CPC Class Codes: A61B 8/0808 for diagnosis of the brain
• CPC Class Codes: A61B 8/0816 using echo-encephalography
• CPC Class Codes: G01N 2291/048 Transmission, i.e. analysed material between transmitter and receiver

Abstract

An ultrasonic instrument is disclosed herein which is particularly adapted for locating the midline structure of a brain relative to the geometric center line of a head. The instrument includes means for automatically producing a first indication representing the geometric center line of the head and a pair of indications representing the distances between the midline structure and the two opposite sides of the head. These three indications are all juxtaposed whereby they may be directly compared with each other to positively identify the position of the midline structure and its location relative to the geometric centerline of the head.

Claims

1. An encephalograph of the class described including the combination of a pair of ultrasonic transducers adapted to be acoustically coupled to the opposite sides of a head containing a brain subdivided by a midline and surrounded by a head, transmitter means and receiver means coupled to said transducers and effective to energize said transducers whereby pulses of ultrasonic energy are transmitted into a head and puLses of ultrasonic energy are received from said head, said receiver means effective to produce electrical signals corresponding to said received ultrasonic energy, a clock coupled to said transmitter and receiver means for synchronizing the transmitting and receiving times of the ultrasonic energy, timing means coupled to the clock and effective to generate timing pulses which define frame intervals, a control coupled to said timing means and to said transmitter means and receiver means, said control being effective to energize said transducers in a first mode during a first frame interval whereby pulses of ultrasonic energy are transmitted into the head from the first side thereof and echoes of the energy reflected from the midline are received, said receiver means being effective during said first frame to produce a first signal which corresponds to the position of the midline relative to the first side, said control being effective to energize said transducers in a second mode during a second frame interval whereby pulses of ultrasonic energy are transmitted into the head from the second side and echoes of the energy reflected from the midline are received, said receiver means being effective during said second frame to produce a second signal which corresponds to the position of the midline relative to the second side, said control being effective to energize the transducers in a third mode during a third frame interval whereby pulses of ultrasonic energy are transmitted into the head from one side and received at the opposite side, said receiver means being effective during said third frame to produce a third signal which corresponds to the space between said sides, an output coupled to said receiver means for comparing said first, second and third signals and indicating the positions of the midline relative to the centerline and between the opposite sides of the head, an automatic gain control means coupled to said receiver means and responsive to at least one of said signals and effective to vary the gain of said receiver means to maintain the amplitude of said signals substantially constant, said automatic gain control means including a gate coupled to receive signals from said receiver means and to be responsive to said timing means for inhibiting signals from said receiver means upon receipt of third signals from said control and passing first and second signals from said control, normally closed video signal gating means coupled to said gate in said gain control means including a control input coupled to said clock for operating said video gating means in synchronism therewith, delay means coupled between said clock and said video signal gating means for delaying said signal from said clock by a time less than that required to receive said midline signals, and peak detector means coupled to said video signal gating means and coupled to said receiver means, said peak detector means being effective to vary the gain of said receiver means in response to the amplitude of said peak detector means, said peak detector means being coupled to said clock to reset said peak detector means at the end of each through transmission signal.