Quantitative ultrasonic imaging for tissue characterization

This presentation will illustrate relationships between physical acoustics and ultrasonic imaging for medical diagnosis. Ultrasonic tissue characterization is designed to complement two‐dimensional echocardiography by providing information in addition to that derived from an assessment of tissue dimension and motion. The hypothesis is that indices based on (frequency‐dependent) backscatter and attenuation can provide a noninvasive tool for the early diagnosis of diverse disease processes including ischemia and cardiomyopathy. Differentiation between mature infarct and acutely ischemic myocardium, which might benefit from reperfusion by angioplasty or thrombolysis, appears to be feasible on the basis of the frequency dependence of backscatter, which is lower in zones of infarct than in acutely ischemic or normal myocardium. Two‐dimensional images are formed from scans made with the direction of propagation of ultrasound at varying angles relative to the local fiber orientation of the myocardium. Backscatte...