Apparatus for ultrasonic echo-encephalography

Claim 1

An apparatus for ultrasonic echo encephalography comprising: a first transducer (A) for emitting and receiving pulses of ultrasonic energy; a first ultrasonic pulse generating means (SA) and a first ultrasonic electric pulse receiving means (MA) for said first transducer; a first electric wave transmission channel from said first pulse generator to said first transducer to supply electric energy at a predetermined ultrasonic frequency to said first transducer for emitting ultrasonic acoustic energy for propagation through the skull when said transmission channel is operative; a first electric wave receiving channel from said first transducer to said first pulse receiving means for supplying said receiver with electric energy at ultrasonic frequencies corresponding to the acoustic ultrasonic energy impinging upon said first transducer when said first receiving channel is operative; a corresponding second transducer (B) for cooperation with said first transducer when said two transducers are positioned at the tEmples on opposite sides of the skull of a patient to be examined; corresponding second pulse generating means (SB) and second receiving means (MB) for said second transducer; second transmission and receiving channels interconnecting said second pulse generating means and said second receiving means; a cyclically operating sequence control means (T) including as a part thereof a primary timing oscillator (VI) for generating primary timing pulses functioning as one apparatus primary operating cycle divided into four equal successive time periods I, II, III, IV; means controlled by said sequence control means for activating the appropriate channels to operate the first transducer as an acoustic transmitter only at the beginning of periods I and III for a duration small in comparison to an entire period and to operate the second transducer similarly for periods II and IV; means controlled by said sequence control means for activating appropriate channels to operate the first transducer as an acoustic receiver during period I after said first transducer has ceased transmitting and during period IV after the second transducer has ceased transmitting, and to operate the second transducer as an acoustic receiver during period II after said transducer has ceased transmitting and during period III after the first transducer has ceased transmitting; a cathode ray tube (K) having X-(horizontal) deflecting means (X1, X2) and Y-(vertical) deflecting means (Y1, Y2); means for generating a linear X-sweep voltage (SG) varying between two constant positive and negative values (U) having similar absolute values; means controlled from said sequence control means (T) for synchronizing the sweep voltage so that at the beginning of each time period I, II, III and IV, the sweep voltage is at maximum absolute value and varies linearly during a period to the oppositely poled absolute value and reaches such value prior to the end of the timing period and remains at such value to the end of the timing period, said primary timing oscillator operating at such a repetition rate that each time period is a bit longer than the transit time for a round trip through the skull for an ultrasonic pulse; means for applying said sweep voltages to the X-deflecting means, the change in sweep voltage polarity during periods I and III causing the sweep to go in a positive going sense between sweep limits and to reverse sweep in a negative going sense during periods II and IV; signal channels between the Y-deflecting means on the one hand and each of the outputs of said pulse receiving means (MA and MB) on the other hand; means controlled by said sequence control means (T) for activating the channel from the first pulse receiving means (MA) to said Y-deflecting means to provide signals of one polarity during period I and for activating the other channel from the second pulse receiving means (MB) to said Y-deflecting means to provide signals of opposite polarity during period II; said transducers and direction X-sweep being so arranged that for example the left transducer will correspond functionally with the X-sweep beginning from the left and the right transducer will correspond functionally with the X-sweep beginning from the right; and whereby the tube display, insofar as left and right are concerned, is naturally associated with the left and right parts of the skull, the X-sweep time in either direction of sweep locating the skull center on the X-sweep at the midpoint of each sweep.

Claim 2

An apparatus for ultrasonic echo encephalography comprising: a first transducer (A) for emitting and receiving pulses of ultrasonic energy; a first ultrasonic pulse generating means (SA) and a first ultrasonic electric pulse receiving means (MA) for said first transducer; a first electric wave transmission channel from said first pulse generator to said first transducer to supply electric energy at a predetermined ultrasonic frequency to said first transducer for emitting ultrasonic acoustic energy for propagation through the skull when said transmission channel is operative; a first electric wave receiving channel from said first transducer to said first pulse receiving means for supplying said receiver with electric energy at ultrasonic frequencies corresponding to the acoustic ultrasonic energy impinging upon said first transducer when said first receiving channel is operative; a corresponding second transducer (B) for cooperation with said first transducer when said two transducers are positioned at the tEmples on opposite sides of the skull of a patient to be examined; corresponding second pulse generating means (SB) and second receiving means (MB) for said second transducer; second transmission and receiving channels interconnecting said second pulse generating means and said second receiving means; a cyclically operating sequence control means (T) including as a part thereof a primary timing oscillator (VI) for generating primary timing pulses functioning as one apparatus primary operating cycle divided into four equal successive time periods I, II, III, IV; means controlled by said sequence control means for activating the appropriate channels to operate the first transducer as an acoustic transmitter only at the beginning of periods I and III for a duration small in comparison to an entire period and to operate the second transducer similarly for periods II and IV; means controlled by said sequence control means for activating appropriate channels to operate the first transducer as an acoustic receiver during period I after said first transducer has ceased transmitting and during period IV after the second transducer has ceased transmitting, and to operate the second transducer as an acoustic receiver during period II after said transducer has ceased transmitting and during period III after the first transducer has ceased transmitting; a cathode ray tube (K) having X-(horizontal) deflecting means (X1, X2) and Y-(vertical) deflecting means (Y1, Y2); means for generating a linear X-sweep voltage (SG) varying between two constant positive and negative values (U) having similar absolute values; means controlled from said sequence control means (T) for synchronizing the sweep voltage so that at the beginning of each time period I, II, III and IV, the sweep voltage is at maximum absolute value and varies linearly during a period to the oppositely poled absolute value and reaches such value prior to the end of the timing period and remains at such value to the end of the timing period, said primary timing oscillator operating at such a repetition rate that each time period is a bit longer than the transit time for a round trip through the skull for an ultrasonic pulse; means for applying said sweep voltages to the X-deflecting means, the change in sweep voltage polarity during periods I and III causing the sweep to go in a positive going sense between sweep limits and to reverse sweep in a negative going sense during periods II and IV; signal channels between the Y-deflecting means on the one hand and each of the outputs of said pulse receiving means (MA and MB) on the other hand; means controlled by said sequence control means (T) for activating the channel from the first pulse receiving means (MA) to said Y-deflecting means to provide signals of one polarity during period I and for activating the other channel from the second pulse receiving means (MB) to said Y-deflecting means to provide signals of opposite polarity during period II; said transducers and direction X-sweep being so arranged that for example the left transducer will correspond functionally with the X-sweep beginning from the left and the right transducer will correspond functionally with the X-sweep beginning from the right; and whereby the tube display, insofar as left and right are concerned, is naturally associated with the left and right parts of the skull, the X-sweep time in either direction of sweep locating the skull center on the X-sweep at the midpoint of each sweep.

Claim 3

An apparatus for ultrasonic echo encephalography comprising: a first transducer (A) for emitting and receiving pulses of ultrasonic energy; a first ultrasonic pulse generating means (SA) and a first ultrasonic electric pulse receiving means (MA) for said first transducer; a first electric wave transmission channel from said first pulse generator to said first transducer to supply electric energy at a predetermined ultrasonic frequency to said first transducer for emitting ultrasonic acoustic energy for propagation through the skull when said transmission channel is operative; a first electric wave receiving channel from said first transducer to said first pulse receiving means for supplying said receiver with electric energy at ultrasonic frequencies corresponding to the acoustic ultrasonic energy impinging upon said first transducer when said first receiving channel is operative; a corresponding second transducer (B) for cooperation with said first transducer when said two transducers are positioned at the temples on opposite sides of the skull of a patient to be examined; corresponding second pulse generating means (SB) and second receiving means (MB) for said second transducer; second transmission and receiving channels interconnecting said second pulse generating means and said second receiving means; a cyclically operating sequence control means (T) including as a part thereof a primary timing oscillator (VI) for generating primary timing pulses functioning as one apparatus primary operating cycle divided into four equal successive time periods I, II, III, IV; means controlled by said sequence control means for activating the appropriate channels to operate the first transducer as an acoustic transmitter only at the beginning of periods I and III for a duration small in comparison to an entire period and to operate the second transducer similarly for periods II and IV; means controlled by said sequence control means for activating appropriate channels to operate the first transducer as an acoustic receiver during period I after said first transducer has ceased transmitting and during period IV after the second transducer has ceased transmitting, and to operate the second transducer as an acoustic receiver during period II after said second transducer has ceased transmitting and during period III after the first transducer has ceased transmitting; a cathode ray tube (K) having X-(horizontal) deflecting means (X1, X2) and Y-(vertical) deflecting means (Y1, Y2); means for generating a linear X-sweep voltage (SG) varying between two constant positive and negative values (U) having similar absolute values; means controlled from said sequence control means (T) for synchronizing the sweep voltage so that at the beginning of each time period I, II, III and IV, the sweep voltage is at maximum absolute value and varies linearly during a period to the oppositely poled absolute value and reaches such value prior to the end of the timing period and remains at such value to the end of the timing period, said primary timing oscillator operating at such a repetition rate that each time period is a bit longer than the transit time for a round trip through the skull for an ultrasonic pulse; means for applying said sweep voltages to the X-deflecting means, the change in sweep voltage polarity during periods I and III causing the sweep to go in a positive going sense between sweep limits and to reverse sweep in a negative going sense during periods II and IV; signal channels between the Y deflecting means on the one hand and each of the outputs of said pulse receiving means (MA and MB) on the other hand; means controlled by said sequence control means (T) for activating the channel from the first pulse receiving means (MA) to said Y-deflecting means to provide signals of one polarity during period I and for activating the other channel from the second pulse receiving means (MB) to said Y-deflecting means to provide signals of opposite polarity during the period II; said transducers and direction X-sweep being so arranged that for example the left transducer will correspond functionally with the X-sweep beginning from the left and the right transducer will correspond functionally with the X-Sweep beginning from the right; whereby the tube display, insofar as left and right are concerned, is naturally associated with the left and right parts of the skull, the X-sweep time in either direction of sweep locating the skull center on the X-sweep at the midpoint of each sweep; means (FO) responsive to said sweep voltage for detecting and indicating a first instant during each one of said third and fourth periods (III, IV) coincident with the passage of said sweep voltage of its midway value between said two constant voltage levels (+U, -U); means (G10, G11) controlled by said sequence control means (T) and responsive to the output signals of said pulse receiving means (MA, MB) for detecting and indicating during each one of said third and fourth period (III, IV) a second instant coincident with the reception at one of said first and second transducer means of a pulse of ultrasonic energy emitted from the opposite one of said first and second transducer means; and means (V5, V6) for determining any time different between said first instant and said second instant during each one of said third and fourth cycles (III, IV) and generating a signal representing said time difference, and means for applying said signal as a correction signal to said sweep voltage generating means (SG) for correcting the rate of change of said sweep voltage in a sense to reducing said time difference.

Claim 4

An apparatus for ultrasonic echo encephalography comprising: a first transducer (A) for emitting and receiving pulses of ultrasonic energy; a first ultrasonic pulse generating means (SA) and a first ultrasonic electric pulse receiving means (MA) for said first transducer; a first electric wave transmission channel from said first pulse generator to said first transducer to supply electric energy at a predetermined ultrasonic frequency to said first transducer for emitting ultrasonic acoustic energy for propagation through the skull when said transmission channel is operative; a first electric wave receiving channel from said first transducer to said first pulse receiving means for supplying said receiver with electric energy at ultrasonic frequencies corresponding to the acoustic ultrasonic energy impinging upon said first transducer when said first receiving channel is operative; a corresponding second transducer (B) for cooperation with said first transducer when said two transducers are positioned at the temples on opposite sides of the skull of a patient to be examined; corresponding second pulse generating means (SB) and second receiving means (MB) for said second transducer; second transmission and receiving channels interconnecting said second pulse generating means and said second receiving means; a cyclically operating sequence control means (T) including as a part thereof a primary timing oscillator (VI) for generating primary timing pulses functioning as one apparatus primary operating cycle divided into four equal successive time periods I, II, III, IV; means controlled by said sequence control means for activating the appropriate channels to operate the first transducer as an acoustic transmitter only at the beginning of periods I and III for a duration small in comparison to an entire period and to operate the second transducer similarly for periods II and IV; means controlled by said sequence control means for activating appropriate channels to operate the first transducer as an acoustic receiver during period I after said first transducer has ceased transmitting and during period IV after the second transducer has ceased transmitting, and to operate the second transducer as an acoustic receiver during period II after said second transducer has ceased transmitting and during period III after the first transducer has ceased transmitting; a cathode ray tube (K) having X-(horizontal) deflecting means (X1, X2) and Y-(vertical) deflecting means (Y1, Y2); means for generating a linear X-sweep voltage (SG) varying between two constant positive and negative values (U) having similar absolute values; means controlled from said sequence control means (T) for synchronizing the sweep voltage so that at the beginning of each time period I, II, III and IV, the sweep voltage is at maximum absolute value and varies linearly during a period to the oppositely poled absolute value and reaches such value prior to the end of the timing period and remains at such value to the end of the timing period, said primary timing oscillator operating at such a repetition rate that each time period is a bit longer than the transit time for a round trip through the skull for an ultrasonic pulse; means for applying said sweep voltages to the X-deflecting means, the change in sweep voltage polarity during periods I and III causing the sweep to go in a positive going sense between sweep limits and to reverse sweep in a negative going sense during periods II and IV; signal channels between the Y deflecting means on the one hand and each of the outputs of said pulse receiving means (MA and MB) on the other hand; means controlled by said sequence control means (T) for activating the channel from the first pulse receiving means (MA) to said Y-deflecting means to provide signals of one polarity during period I and for activating the other channel from the second pulse receiving means (MB) to said Y-deflecting means to provide signals of opposite polarity during the period II; said transducers and direction X-sweep being so arranged that for example the left transducer will correspond functionally with the X-sweep beginning from the left and the right transducer will correspond functionally with the X-Sweep beginning from the right; whereby the tube display, insofar as left and right are concerned, is naturally associated with the left and right parts of the skull, the X-sweep time in either direction of sweep locating the skull center on the X-sweep at the midpoint of each sweep; means (FO) responsive to said sweep voltage for detecting and indicating a first instant during each one of said third and fourth periods (III, IV) coincident with the passage of said sweep voltage of its midway value between said two constant voltage levels (+U, -U); means (G10, G11) controlled by said sequence control means (T) and responsive to the output signals of said pulse receiving means (MA, MB) for detecting and indicating during each one of said third and fourth period (III, IV) a second instant coincident with the reception at one of said first and second transducer means of a pulse of ultrasonic energy emitted from the opposite one of said first and second transducer means; and means (V5, V6) for determining any time different between said first instant and said second instant during each one of said third and fourth cycles (III, IV) and generating a signal representing said time difference, and means for applying said signal as a correction signal to said sweep voltage generating means (SG) for correcting the rate of change of said sweep voltage in a sense to reducing said time difference.