Geometric distortion of area in medical ultrasound images

摘要: Medical ultrasound scanners are typically calibrated to the soft tissue average of 1540 m s$^{-1}$. In regions different sound speed, for example, organs and tumours, $B$-scan image then becomes a distortion true cross-section, due misrepresentation length refraction. To quantify this we develop general geometric ray model an object with atypical speed embedded in ambient medium. We analyse ensuing area circular elliptical objects, mapping it out as function key parameters, including mismatch, size its elongation. find that can become significant, even small-scale mismatches. Our findings verified by imaging test object.