Three-dimensional prostate imaging and tissue typing

Abstract

Three-dimensional (3-D) depictions of ultrasonic scan data have been developed in our laboratories for visualizing tissue properties and structure in several medical applications including characterization of prostatic and ophthalmic tissues. Data for 3-D depictions are acquired as a set of parallel ultrasonic scans and are displayed as volume or surface renderings or as interactively dissectable blocks. Acquired data consist of digitized radio-frequency (rf) echo signals. Tissue-typing information is based on parameters derived from linear-regression analyses of normalized power spectra of the digitized rf echo-signal data. Tissue properties, such as scatterer size, are computed from spectral parameter values. Tissue typing is performed by comparing computed parameter values from an unknown tissue with database values associated with known tissue types. Images portraying spectral parameter values, scatterer properties, or most-likely tissue type have been developed. Three-dimensional presentations are generated from sets of scan-plane data using desktop computers or imaging workstations. Volumes can be examined in several ways, e.g., by dynamically presenting the entire 3-D volume as a tilting or a rotating transparent rendering. Three-dimensional images of the prostate gland facilitate visualization of cancerous regions warranting biopsy. [Research supported, in part, by the National Cancer Institute and the National Eye Institute.]