Abstract:
:The dearth of information on the physical processes involved in the propagation of ultrasound in tissue and the growing need for such information are discussed. The physical nature of the ultrasonic diagnostic process in considered in terms of a wave phenomenon and the limitations and advantages of frequency spectral analysis as a means of obtaining information are briefly analysed. A description is given of an experimental measuring system using a time-gate to select echoes scattered from a particular volume at a depth in soft tissues. The influence of attenuation by overlying tissue and the choice of the duration of the acceptance gate on the frequency spectra obtained are considered. The paper reports some backscattering measurements on formalin-fixed samples of human fat, liver and spleen in the frequency range 0-5-5-0 MHz. The results suggest that the approach may have diagnostic value in a clinical situation, in the characterization of structure in specific volumes of soft human tissue.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Chivers RC,Hill CRdoi
10.1088/0031-9155/20/5/009subject
Has Abstractpub_date
1975-09-01 00:00:00pages
799-815issue
3eissn
0031-9155issn
1361-6560journal_volume
20pub_type
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