Meckel腔：头颅断层标本与MRI对照研究

为Ｍｅｃｋｅｌ腔的影像学诊断和显微外科学提供基础资料。材料和方法：利用３５具头颅连续断层标本、１０３例正常头颅ＭＲＩ和３６例增强ＭＲＩ，研究Ｍｅｃｋｅｌ腔及三叉神经节显示的断面、形态、大小和毗邻。结果：Ｍｅｃｋｅｌ腔为由颅后窝向颅中窝后内侧部分突入的硬脑膜陷凹，其内容纳三叉神经节和三叉池。在轴位和冠状Ｔ１ＷＩ上，Ｍｅｃｋｅｌ腔呈现卵圆形低信号影，其内的三叉神经节显示为点状、条状或小片状等信号影，显示率为３４％；在增强扫描中，三叉神经节有强化，显示率达７７％，但比实际标本要小；矢状Ｔ１ＷＩ上，Ｍｅｃｋｅｌ腔呈开口朝向后方的“Ｃ”形低信号影；Ｔ２ＷＩ上，Ｍｅｃｋｅｌ腔呈卵圆形高信号影，三叉神经节不能显示。Ｍｅｃｋｅｌ腔的大小在断层标本和ＭＲＩ上无显著性差异。结论：ＭＲＩ可清晰显示Ｍｅｃｋｅｌ腔，以冠状位显示最佳，三叉神经节可部分显示；增强扫描可明显提高三叉神经节的显示率。

Meckel Cave:Comparative Study Between Cadaver Sections and MR Images

Purpose:To provide the basic data for imaging diagnosis and microsurgery of Meckel cave.Materials and methods:35 sets of cadaver heads were cut into serial slices for studying the shape,size and adjacent relationships of Meckel cave and trigeminal ganglion.Meanwhile,the head MRIs of 103 normal adults with pre-contrast and those of 36 with post-contrast were compared with the corresponding sections for structures and statistics.Results:Meckel cave is a dural recess extending from the posterior fossa into the medial posterior portion of the middle cranial fossa,within it lies the trigeminal ganglion and its cistern.On transverse and coronal T1-weighted images,Meckel cave shows an oval hypointense signal,and the trigeminal ganglion shows a dot,stripe or small focus of hyperintense signal which is seen on 34% of the images.The ganglions were enhenced and seen on 77% post-contrast images.It is smaller on MR images than on cadaver sections.On sagittal T1 weighted images,Meckel cave shows a C-like hypointense signal openning poetesionly.On T2weighted images,Meckel cave manifests an oval hyperintense signal,and the trigeminal ganglion can not be seen.There was no significant difference in the size of Meckel cave on cadaver sections and MRI.Conclusion:MRI can show Meckel cave clearly and the trigeminal ganglion partially.It is best seen on coronal T1weighted images.Conventional enhenced MRI is