Ultrasonic temperature measurement apparatus

• US 4,817,615 A
• Filed: 12/12/1986
• Issued: 04/04/1989
• Est. Priority Date: 12/13/1985
• Status: Expired due to Term

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Ueno, Shinichiro, Tone, Masayuki, Fukukita, Hiroshi, Yano, Tsutomu
• Primary Examiner(s): Jaworski, Francis
• Assistant Examiner(s): MANUEL, GEORGE C
• Application Number:
  US06/941,221
• Time in Patent Office: 844 Days
• Field of Search: 128/660, 128/24 A, 128/736, 128/660, 73/861.01
• US Class Current: 600/438
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• CPC Class Codes: A61B 8/5223 for extracting a diagnostic or physiological parameter from medical diagnostic data for algorithms to analyse biomedical images G06T7/0012
• CPC Class Codes: G01H 5/00 Measuring propagation velocity of ultrasonic, sonic or infrasonic waves , e.g. of pressure waves
• CPC Class Codes: G01S 7/52026 Extracting wanted echo signals Doppler systems G01S15/50; Doppler short range imaging systems G01S15/8979
• CPC Class Codes: G01S 7/52036 using analysis of echo signal for target characterisation
• CPC Class Codes: G16H 50/30 for calculating health indices; for individual health risk assessment

Abstract

An ultrasonic diagnostic apparatus detects variations of an acoustic characteristic to obtain the fluctuation of temperature within a body to be examined. The ultrasonic diagnostic apparatus includes an ultrasonic transducer for transmitting an ultrasonic wave and receiving the reflected ultrasonic wave which is in turn converted into an electric signal. The signal is phase-detected in accordance with a plurality of gate intervals or a plurality of window interval to detect a phase difference therebetween. The relative variation of velocity dispersion before and after heating of the body is obtained on the basis of the phase variation resulting from the variation of the ultrasonic drive frequency.

Claims

1. An ultrasonic measuring apparatus comprising:

ultrasonic transducer means driven in reponse to a plurality of frequencies for receiving ultrasonic waves reflected from a body to be examined and for converting the reflected ultrasonic waves into electric signals;

phase detecting means for phase-detecting the signal from said ultrasonic transducer means in synchronism with the frequencies;

timing generator means for generating a plurality of gate intervals in synchronism with the driving of said ultrasonic transducer means; and

computing means for obtaining phase differences at the plurality of gate intervals for the plurality of frequencies in accordance with an output of said phase detecting means indicative of the result of the phase-detection and for computing a dispersion data, which is a variation component of the phase difference between the frequencies, and the relative variation between the dispersion data.

2. An ultrasonic measuring apparatus as claimed in claim 1, wherein the dispersion data is obtained a plurality of times and the obtained dispersion data is averaged.

3. An ultrasonic measuring apparatus comprising:

ultrasonic transducer means for receiving an ultrasonic wave reflected from a body to be examined and for converting the reflected ultrasonic wave into an electric signal;

amplifier means for amplifying the signal from said ultrasonic transducer means;

discrete Fourier transformation means for performing a discrete Fourier transformation in terms of the output of said amplifier with a plurality of window intervals;

phase difference computing means for obtaining a phase difference of the output data from said discrete Fourier transformation means in accordance with the plurality of window intervals;

frequency change rate computing means for obtaining the rate of change of frequency in terms of the output data from said phase difference computing means; and

temperature change rate computing means for obtaining the rate of change of temperature on the basis of the obtained rate of change of frequency.

4. An ultrasonic measuring apparatus as claimed in claim 3, wherein said phase difference computing means is arranged so that phase difference is obtained after a phase correction is performed in accordance with the gain level of said amplifier means.

5. An ultrasonic measuring apparatus comprising:

means for generating a plurality of drive pulses whose frequencies are different from each other;

timing control means for controlling phases between the plurality of drive pulses;

ultrasonic transducer means coupled to said drive pulse generating means;

phase detecting means for performing a phase detection in terms of signals from said ultrasonic transducer means;

means for changing the detection frequency of said phase detecting means;

gate interval generating means for generating a plurality of gate intervals in synchronism with said drive pulse generating means;

phase difference computing means for obtaining a phase difference in terms of the outputs of said phase detecting means in accordance with the gate intervals; and

phase shift comprising means for obtaining the difference between the outputs of the phase difference computing means corresponding to different conditions of said timing control means or corresponding to different detection frequencies,

6. An ultrasonic measuring apparatus as claimed in claim 5, further comprising elimination computing means for obtaining the ratio of phase velocities at different frequencies on the basis of said phase shift computing means.

7. An ultrasonic measuring apparatus comprising:

means for generating a low frequency ultrasonic pulse to illuminate a body to be examined;

ultrasonic means for transmitting to a portion of the body illuminated by said low frequency ultrasonic pulse a high frequency ultrasonic pulse, having a frequency higher than that of said lower frequency ultrasonic pulse; and

computing means, obtaining phase differences at a plurality of gate intervals generated for said low and high frequencies, for computing the rate of change in a received signal with the passage of time of an output signal of said ultrasonic transmitting means corresponding to said high frequency ultrasonic pulse with respect to a specific depth within the body.

8. An ultrasonic measuring apparatus comprising:

ultrasonic vibrator means for transmitting and receiving an ultrasonic wave;

transmission timing generating means for generating a transmission timing signal;

transmission pulse means for generating a transmission pulse in synchronism with said transmission timing signal;

gate pulse generating means for generating a gate pulse in synchronism with said transmission timing signal;

switching timing means for generating a switching timing control signal on the basis of said gate pulse;

transmission pulse switching means provided between said ultrasonic vibrator means and transmission pulse means for switching the transmission pulse from said transmission pulse means on the basis of the switching timing control signal;

varaiable frequency generator means coupled to said transmission pulse means;

amplifier means for amplifying the signal corresponding to the wave received by said ultrasonic vibrator;

phase detection signal generating means for generating a phase detection signal in synchronism with a clock from said variable frequency generator means;

first and second phase detectors for quadrature-phase-detecting the output of said amplifier means in accordance with the phase detection signal;

first and second integrators for integrating the outputs of said first and second phase detectors within interval of the gate pulse produced in synchronism with the transmission timing signal;

first and second A/D converters for converting the outputs of said first and second integrators into digital values;

first and second memory sections for receiving the output value of said first A/D converter through first memory switching means controlled in accordance with the switching timing control signal;

first subtraction means for calculating the difference between the outputs of said first and second memory sections;

thrid and fourth memory sections for receiving the output value of said second A/D converter through second memory switching means controlled in accordance with the switching timing control signal;

second subtraction means for calculating the difference between the outputs of said third and fourth memories; and

computing means for obtaining a phase on the basis of output values of said first and second subtraction means.