脑部脉络膜裂囊肿的MRI诊断

目的:探讨脑部脉络膜裂囊肿的MRI影像学表现及其诊断价值。方法:回顾性分析21例脉络膜裂囊肿的MRI资料,对MRI影像与临床表现之间的关系进行了讨论。结果:21例病灶均位于脉络膜裂内。MRI表现:冠状面呈“双凸透镜”形、卵圆形,矢状面呈卵圆形、“箭头样”表现;内部信号均匀且在各个序列上均呈长T1长T2信号,FLAIR序列示囊肿信号呈低信号。囊壁及其周围无软组织信号,平均大小为0.8cm×1.4cm×1.6cm,病灶周围均无水肿。3例行钆喷替酸葡甲胺(Gd-DTPA)增强扫描后均未见病灶强化。结论:脑部脉络膜裂蛛网膜囊肿是一种良性的先天性发育异常,通常与临床表现无关。由于脉络膜裂囊肿发生在特殊的位置,横轴面扫描易误诊为脑内病变,MRI冠状面及矢状面扫描可做出明确诊断并能够与其他囊性病变相鉴别。

MR Imaging of Choroidal Fissure Cyst of the Brain

Objective To discuss the value of MRI manifestations and MRI scans in the diagnosis of the arachnoid cyst in choroidal fissure of the brain.Methods Characteristic MRI findings in 21 patients with choroidal fissure cyst were retrospectively analyzed,and the correlation between MRI imaging and clinical manifestations was reviewed.Results All lesions located at the area of choroidal fissure.MRI findings were as follows:lesions were displayed as double-convex lens shape or egg shape on coronal imaging and round shape or arrow-head shape on sagittal imaging;They all showed long T1WI and long T2WI signal and low signal in FLAIR series,representing as cystic lesion without detectable soft tissue mass in the cyst wall or adjacent area,with the average size of 0.8 cm×1.4 cm×1.6 cm,and no associated edema.Gd-DTPA was performed in 3 cases and revealed no evidence of enhancement.Conclusion The choroidal fissure cyst of the brain is a benign and congenital developmental abnormality and has minor clinical significanceN Because of its specific anatomic location,the choroidal fissure cysts simulate intraparenchymal cystic lesions on axial images.Coronal and sagittal MRI imaging can be used to delineate its extraaxial location and make the correct diagnosis,and thus,differentiate with other cystic lesions.