四脑室顶位置磁共振成像的临床定量研究

Position of Fastigium of the Fourth Ventricle in the Normal Population and in Patients with Chiari Malformations: A Quantitative Approach with MR Imaging

目的：用ＭＲＩ测量正常国人各性别、年龄组及Ｃｈｉａｒｉ畸形患者的第四脑室顶高距与水平距，以探讨其正常值范围及四脑室顶位置的发育规律。材料与方法：在颅脑（旁）正中矢状面ＳＥＴ１ＷＩ上测量３１７例正常国人和４２例Ｃｈｉａｒｉ畸形及可疑病人的第四脑室顶高距及水平距。正常组按性别、年龄分为１６组，每组２０例（７０岁以上女性组１７例）。ＭＲＩ应用１．０Ｔ全身ＭＲ机，用ｔ检验作统计分析。结果：四脑室顶高距女性为３０．０ｍｍ±１．９ｍｍ，男性为２９．６ｍｍ±２．９ｍｍ～３２．２ｍｍ±３．５ｍｍ；仅部分男性有显著年龄差异，但无显著性别差异。四脑室顶水平距男性为１１．０ｍｍ±１．５ｍｍ，女性为１０．６ｍｍ±１．３ｍｍ，无显著性别、年龄差异。Ｃｈｉａｒｉ畸形的四脑室高距明显低于正常人（Ｐ＜０．０１），可疑组也明显低于部分年龄组正常男性（Ｐ＜０．０５），而其水平距与正常各性别、年龄组的无显著差异（Ｐ＞０．０５）。结论：第四脑室顶位置有一定的生长发育规律，Ｃｈｉａｒｉ畸形常伴四脑室顶下移。

Objective: To determine the normal range of the fastigium by measuring the position of fastigium in patients with Chiari malformations and in the normal Chinese individuals ranged in age from birth to 70 years. Materials and Methods:The vertical and horizontal distance of fastigium (VDF and HDF) on mid or paramidsagittal MR image were measured in 317 subjects without posterior fossa abnormalities or increased intracranial pressure, and in 42 patients with Chiari malformations. The normal subjects were divided into 16 groups according to sex and age, 20 subjects every group with the exception of female group aged over 70 (n=17). MRI data were obtained by a 1.0T MR scanner, and t test was used for statistical analysis.[KG*3〗Results:VDF in females was 30.0mm±1.9mm, showing no age difference. VDF in males ranged from 29.6mm±2.9mm to 32.2mm±3.5mm, having significant age difference in some cases. No statistically significant difference existed between VDF of males and VDF of females. HDF was 11.0mm±1.5mm in males and 10.6mm±1.3mm in females showing no significant difference in sex or age. VDF in patients with Chiari malformations was smaller than that in normal subjects (P<0.05), but the difference in HDF between the normal and Chiari malformation group was of no significance statistically (P>0.05). Conclusion: The position of fastigium, as sex and age was concerned, shows certain growing and developmental behavior, and in patients with Chiari malformations the fastigium position is lower than that in normal subjects.