Combined surface display and reformatting for the three-dimensional analysis of tomographic data

Radiologic examinations increasingly are based on sequences of cross-sectional images. In current clinical applications, the three-dimensional (3D) relationships contained in these examinations must be inferred by the observer through analysis of multiple two-dimensional (2D) images. In this article, methods for the direct display of 3D gray-level data are investigated. In the chosen approach, the 3D presentation of bone and skin surface serves to orient the viewer, while planar reformation and/or transparent projections can be applied for the assessment of soft-tissue structures in regions of interest. The resulting images represent the original image data in a way that is more suitable for observation of 3D relationships than the conventional cross-sectional viewing mode. This may facilitate the diagnostic process and enhance the interpretability of the images. Routine clinical application of this technique requires special computer hardware. Research applications, however, can be performed within tolerable times (10-30 sec/view) with computers found in radiologic research environments.