岩矢角的CT测定在岩锥X线摄影中的应用

The application of CT measurement of the petrous sagittal angle in the petrous radiography

目的评价CT测定头颅指数与岩矢角的动态关系在颞骨岩部X线摄影中的应用价值。方法选择无畸形的正常头颅1000例,在其CT平扫所得骨窗像中应用CT的功能测量岩锥角及头颅的最大前后径与横径,计算出修正的头颅指数,寻求二者之间的动态关系。结果成年男性头颅最大前后径在166mm～195mm之间,最大横径在140mm～163mm之间。头颅指数在76%～93%之间。岩矢角最大范围为51°～66°,其中短头型者平均在58～61之间,中头型者平均在54°～56°之间。成年女性头颅最大前后径在164mm～187mm之间,最大横径在130mm～153mm之间。头颅指数在75%～86%,岩矢角最大范围为51°～66°,其中短头型者平均在55°～57°之间,中头型者平均在53°～54°之间。结论通过CT测量可以方便、精确地计算岩矢角的大小,对于头颅复杂部位的特殊摄影,提高耳部及岩骨等病变的影像诊断具有较高的价值。

Objective To study relation of the petrous-sagittal-angle(PSA) and head index by CT scan and estimate the value of the radiography in petrous bone. Methods 1 000 cases of normal head were scanned by CT, in which the PSA and the maximal anterior-posterior diameter(MAPD) and the maximal left-right diameter(MLRD) were measured to calculate the correctional head index and to find the relation between two factors. Results The ranges of the adult males data were from 166 mm to 195 mm for MAPD and from 140 mm to 163 mm for MLRD ,76 %to 93 %for the head indexes ,and the ranges of rhe PSA were from 51o to 66o,which were 58o to 61o for the short type head and 54o to 56o for the medium type head. The ranges of the adult females data were from 164 mm to 187 mm for MAPD and from 130 mm to 153 mm for MLRD,75 %to 86 %for the head indexes,and the ranges of the PSA were from 51o to 66o, which were 55to 57for short type head and 53to 54for the medium type head. Conclusion The PSA can be accurately calculated by CT measurement, it has very important value in the imaging diagnosis of ear and petrous bone diseases for the head radiography.