Methods 37 cases were examined by orthopantomography and helical scanning of multi-slices spiral CT with 1.25 mm slice thickness.

• 方法37例患者均行曲面体层片和多层螺旋CT轴位扫描；层厚1.；25 mm；采用最大密度投影(MIP)、表面遮盖显示(SSD)和多平面重建(MPR)技术对图像进行重建。