Title :
In-vivo fetal ultrasound exposimetry
Author :
Daft, C.M.W. ; Siddiqi, T.A. ; Fitting, D.W. ; Meyer, R.A. ; O´Brien, W.D., Jr.
Author_Institution :
Dept. of Electr. & Comput. Eng., Illinois Univ., IL, USA
Abstract :
An instrument has been developed to measure the acoustic pressure field during an obstetric ultrasound examination. This permits a more accurate assessment of possible bioeffects since the pressure is sensed at or near the site of the organs under investigation. The ultrasonic field is sampled using a calibrated seven-element linear array hydrophone of PVDF transducers, which is placed as close as possible to the ovary, embryo, or fetus, using a vaginal approach. The RF signals from the hydrophone are digitized at 50 Ms/s, and the maximum amplitude waveform received in the examination is recorded. The output of the clinical B-scanner is calibrated by the hydrophone in a water bath. From the hydrophone measurements, the in-vivo ISPTA, ISPTP, and ISPPA can be computed. Further analysis allows the frequency-dependent tissue attenuation to be assessed
Keywords :
biomedical equipment; biomedical measurement; biomedical ultrasonics; ultrasonic equipment; ultrasonic measurement; PVDF transducers; RF signals; acoustic pressure field measurement; bioeffects assessment; calibrated 7-element linear array hydrophone; clinical B-scanner; embryo; fetus; frequency-dependent tissue attenuation; hydrophone measurements; in vivo fetal ultrasound exposimetry; maximum amplitude waveform; obstetric ultrasound examination; organs; ovary; vaginal approach; water bath; Acoustic measurements; Acoustic transducers; Embryo; Instruments; Pressure measurement; Sonar equipment; Ultrasonic imaging; Ultrasonic transducer arrays; Ultrasonic transducers; Ultrasonic variables measurement;
Conference_Titel :
Ultrasonics Symposium, 1989. Proceedings., IEEE 1989
Conference_Location :
Montreal, Que.
DOI :
10.1109/ULTSYM.1989.67150
