Visceral fat inspection method based on the ultrasound tomographic reconstruction of abdominal tissue sound speed image

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In the present study, investigations and validation experiments were made for the realization of acoustic tomographic visceral fat inspection apparatus based on the observation of ultrasound time of flight data around human abdominal surface. In particular, mechanical scanning system using a facing pair of high sensitivity broad band piezoelectric transducers in low frequency range was developed, so that waves propagated through the long distant intestinal gaseous medium can be detected without suffering sound attenuation. In addition, urethane gel hemi-spheres were attached in front of the transducers to keep good contact between transducer and body surface, regardless of contact angles between them. The facing pair transducers attached on the automated actuator stages for the movement of rotation (720 mm in diameter), translation (600 mm stroke), and pushing (300 mm stroke) were controlled by the computers to move to arbitral positions on the abdominal body surface. On this occasion, … More to minimize the loss of data caused by the avoidance of sound propagation paths intersecting a spine, propagation path was determined so that center of scanning rotation was adjusted to the spine. To this end, contour of the body surface was measured by laser range sensor and spine position was estimated in advance. By this means, the paths were adaptively determined in accordance with patient’s body size and sitting position. In addition, amplitudes of the sound waves were monitored so that contact condition can be controlled at an optimalpushing position regardless of the deviation of the premeasured body surface position. Finally, from the evaluation experiments by using the phantom specimen, it was shown that the measured precision of time of flight data were good enough to reproduce the abdominal sound speed cross sectional profile image. In addition, validity of the proposed visceral fat measurement techniques was confirmed from the results that fat areas can be clearly discriminated from the remaining protein areas with high degree of accuracy. Although the evaluation experiments for human patients were remained as future work, the system was brought to completion which can automatically collect the sound wave data around body surface andmeasure the visceral fat area from the abdominal reconstructed sound speed image. Less