SKELETAL 3-D CT - ADVANTAGES OF VOLUME RENDERING OVER SURFACE RENDERING

Both surface rendering and volume rendering have been extensively appl ied to CT data for 3-D visualization of skeletal pathology. This revie w illustrates potential limitations of each technique by directly comp aring 3-D images of bone pathology created using volume rendering and surface rendering. Surface renderings show gross 3-D relationships mos t effectively, but suffer from more stairstep artifacts and fail to ef fectively display lesions hidden behind overlying bone or located bene ath the bone cortex. Volume-rendering algorithms effectively show subc ortical lesions, minimally displaced fractures, and hidden areas of in terest with few artifacts. Volume algorithms show 3-D relationships wi th varying degrees of success depending on the degree of surface shadi ng and opacity, While surface rendering creates more three-dimensional ly realistic images of the bone surface, it may be of limited clinical utility due to numerous artifacts and the inability to show subcortic al pathology. Volume rendering is a flexible 3-D technique that effect ively displays a variety of skeletal pathology with few artifacts.