【摘要】 目的　通过对颅骨螺旋CT扫描和三维重建参数的选择 ,以获得最佳三维图像。材料与方法　采用干颅、尸头颅各 2个及 2位正常志愿者 ,采用不同层厚和床速的螺旋CT扫描 ,并行不同间隔、不同阈值的表面阴影显示法 (surfaceshadeddisplay ,SSD)三维重建。结果　比较不同扫描参数获得的三维图像 ,发现层厚越薄 ,三维图像越接近实物的实际大小 ,提高螺距不会影响图像的质量 ,且能达到降低层厚的目的 ,用非层厚的整除数间隔重叠重建 ,选择软组织不能成像的最低阈值 ,图像效果最佳。结论　薄的层厚、重叠重建、适当的阈值可获得最佳的颅骨三维图像。更多还原

【Abstract】 Objective To obtain the best 3 D images by optimizing the scanning and reconstruction parameters of skull spiral CT.Materials and Methods Spiral CT scanning with different collimations, bed speed and pitch was performed in 2 dry skulls, 2 cadaveric heads and 2 normal volunteers. 3 D images were obtained by surface shaded display (SSD) with different thresholds, and were compared with each other.Results The comparison of 3 D images using different scanning parameters showed that the thinner the collimation was, the closer to the actual size of the skull the 3 D image would be. Higher pitches did not affect the image and, when used, collimation could be further reduced. When the lowest threshold, at which soft tissue couldn’t show up, was used, and when reconstruction was done by interval which was non integer of collimation, the best quality images could be obtained.Conclusion Thinner collimation scanning, denser overlapping reconstruction and appropriate threshold are the key technical points for obtaining ideal 3 D skull images.更多还原