A PRACTICAL CLINICAL METHOD FOR CONTOUR DETERMINATION IN ULTRASONOGRAPHIC PROSTATE IMAGES

This paper describes a practical method for automated determination of the contour of the prostate in ultrasonographic images. In this metho d, we use specific edge detection techniques, based on nonlinear Lapla ce filtering. Possible edges are located at zero-crossings of the seco nd derivative of the image. The strength of the edge is reflected by t he value of the gradient of the image at that location. Combining the information about location and strength, an edge intensity image is co nstructed from the initial ultrasonographic image. In our method, edge enhancement techniques are performed on the edge intensity image. Edg es that actually represent a boundary are selected and linked: interpo lation techniques are used to fill the gaps between detected boundary edges. The method for contour determination in ultrasonographic images is used for accurate volume measurements in an everyday clinical envi ronment. Its computer implementation is fast, accurate (mean differenc e within 6% of exact volume) and easy to use.