Computerized ultrasonic characterization of ocular tissues

Abstract

Ultrasonic characterization, using digital techniques, is being applied to clinical data gathered in examination of the eye and orbit. Digital rf echo signals are obtained from structures situated within a 7.5 × 20 mm region of the eye. A dedicated minicomputer system is employed to select specific portions of these records for analysis. Using a simple instruction set, a variety of analysis techniques can be chosen to characterize specific types of structures. For example, small ocular tumors are examined with spectrum analysis techniques to delineate surface features, internal scattering characteristics, and shadowing of posterior scatterers such as orbital fat elements. The use of analysis procedures is guided by the display of reconstructed, gray-scale B-scans. Computational results are presented in a variety of display formats (including color-coded and isometric modes) to facilitate recognition of fundamental tissue features. Data are catalogued for continuing evaluation of tissue characteristics that are useful for diagnostic purposes and for refinement of mathematical modeling based on histological preparations resulting from surgery. [Work supported by the NIH.]