Radiology 2000;214:517-522
Hopper Kenneth D., Iyriboz A. Tunc, Wise Scott W., Neuman Joel D., Mauger David T., Kasales Claudia J.
PURPOSE: To evaluate computed tomographic virtual reality with volumetric versus surface rendering.
MATERIALS AND METHODS: Virtual reality images were reconstructed for 27 normal or pathologic colonic, gastric, or bronchial structures in four ways: the transition zone (a) reconstructed separately from the wall by using volume rendering; (b) with attenuation equal to air; (c) with attenuation equal to wall (soft tissue); (d) with attenuation halfway between air and wall. The four reconstructed images were randomized. Four experienced imagers blinded to the reconstruction graded them from best to worst with predetermined criteria.
RESULTS: All readers rated images with the transition zone as a separate structure as overwhelmingly superior ( P < .001): Nineteen cases had complete concurrence among all readers. The best of the surface-rendering reconstructions had the transition zone attenuation equal to the wall attenuation (P < .001). The third best reconstruction had the transition zone attenuation equal to the air attenuation, and the worst had the transition zone attenuation halfway between the air and wall attenuation.
CONCLUSION: Virtual reality is best with volume rendering, with the transition zone (mucosa) between the wall and air reconstructed as a separate structure.