脉络膜裂蛛网膜囊肿的解剖学基础及MRI表现

Anatomic basis and MRI features of arachnoid cyst in choroidal fissure

目的:探讨脑部脉络膜裂蛛网膜囊肿的解剖学基础和MR表现,提高对它的认识。方法:回顾性分析32例脉络膜裂蛛网膜囊肿病人的MR资料(其中5例做了增强扫描),并观察12例尸体脑部断层解剖标本。结果:32例均表现为脉络膜裂内类圆形、卵圆形或纺锤形脑脊液信号灶(增强扫描无强化),6例解剖标本脉络膜裂区可见多发小间隙,其中1例可见脉络膜裂囊肿。结论(:1)脉络膜裂蛛网膜囊肿是一种良性的先天性发育异常,脉络膜裂区组织结构较疏松,可能与脉络膜裂囊肿形成有关。(2)利用MR的多种序列及多方位扫描,可做出明确诊断。

Objective： To study anatomic basis and MRI features of the arachnoid cyst in choroidal fissure. Methods： MRI data from 32 patients with choroidal fissure cyst （3 of them endured enhancement scan） were retrospectively analyzed. At the same time, sectional specimens from 12 cadaveric heads were observed. Results： The cysts situated within the choroidal fissure for all cases, and showed round or spindle lesion signals with the same intensity as CSF. There was no abnormal enhancement in cases scaned enhancely. Many small gaps appeared at the choroidal fissure areas in 6 anatomical specimens, one of them showed choroidal fissure cyst. Conclusions： （l）The choroidal fissure cyst is a nonmalignant congenital developmental abnormality. Relatively loose structural features of the choroidal fissure area devote to the formation of the cyst. （2）Using a variety of sequences and multi-directional scanning, arachnoid cyst can be diagnosed definitely.