106例正常人正中矢状面颅底及颅颈交界距离及角度的MRI测量

Measurements of the distance and the angle at the cranial base and the cranio-cervical junction on MR central sagittal plane of 106 normal Chinese

目的:建立颅底及颅颈交界(CCJ)夹角的MRI正常参考标准并提出MRI诊断颅底陷入症(BI)的新方法。方法:在MRI正中矢状面T2WI上测量106例正常人及2例BI病人鞍背后上缘处蛛网膜下腔颅底缘夹角(ACBM)、CCJ处蛛网膜下腔前缘夹角(AACC)和CCJ处蛛网膜下腔后缘夹角(APCC)。结果:ACBM、AACC的正常范围,男性分别为105.4°～129.5°、139.2°～163.9°,女性分别为110.1°～131.2°、135.5°～160.7°。APCC正常范围为115.5°～147.7°。BI病人中,男女各1例,其ACBM为155.8°和146.8°,AACC为118.5°和121.1°。结论:所建立的ACBM、AACC的正常范围及AACC与ACBM和APCC大小比较,可用于BI的MRI诊断。

Objective: To establish reference criteria of normal angle at the cranial base and the cranio-cervical junction(CCJ)on MRI and to create a new method for diagnosis of basilar invagination(BI) by MRI. Methods: The angle of the cranial base margin of the subarachnoid space(SAS) at the superior posterior margin of the dorsum sellae(ACBM), the angle of the anterior margin of the SAS at the CCJ(AACC) and the angle of the posterior margin of the SAS at the CCJ(APCC) were measured on MRI T2WI of the central sagittal slices at the cranial bases and the CCJs of 106 cases of normal Chinese and two patients with BI. Results: The normal ranges of ACBM and AACC are 105.4°～129.5° and 139.2°～163.9° in male, and 110.1°～131.2° and 135.5°～160.7° in female. APCC normally ranges from 115.5° to 147.7°. ACBM and AACC in one male patient versus one female patient with BI were 155.8° versus 146.8° and 118.5° versus 121.1° respectively. Conclusion: The normal ranges of ACBM and AACC, and the comparison of the size of AACC with that of ACBM and APCC can be used in MRI for the diagnosis of BI.