颅内表皮样囊肿的MRI表现(32例报告并文献复习)

目的　研究颅内表皮样囊肿的ＭＲ影像特征。方法　经手术病理证实的表皮样囊肿患者３２ 例，男９ 例，女２３ 例，全部行ＭＲ检查。结果　典型表现者２９ 例，占９１％ ；Ｔ１ＷＩ上表现为低信号，有时不均匀。非典型表现者３ 例，占９％ ；Ｔ１ＷＩ上肿瘤实质内为短Ｔ１ 高信号。２０ 例增强扫描中，８例无强化，１１ 例边缘强化，１ 例肿瘤周边和肿瘤内部呈条索样分隔物增强。Ｔ２ＷＩ上，１７ 例肿瘤信号等于脑脊液信号，１ 例明显高于脑脊液信号，１４ 例肿瘤内可见斑点状等信号。结论　典型常见的表皮样囊肿是Ｔ１ 低信号，在Ｔ１ＷＩ上肿瘤质地欠均匀；非典型罕见的表皮样囊肿呈Ｔ１ 高信号，信号形成原因是高浓度蛋白质所致，并非脂类物质。

The MR imaging manifestations of intracranial epidermoid cyst (report of 32 cases and literature review)

Objective To study the MR imaging characteristics of intracranial epidermoid tumors Methods 32 patients (9 male, 23 female) with histologically proven intracranial epidermoid tumors were included in this study Results The epidermoid tumors usually exhibited heterogeneously low signal intensity on T 1 weighted images (91%) and sometimes high signal intensity on T 1 weighted images (9%) On T 2WI,high signal intensity was demonstrated In the 20 cases administrating contrast medium, 8 cases had no enhancement at all, 11 cases rim enhancement, and 1 case rim enhancement and septa enhancement within the tumor Conclusions Typical epidermoid tumors commonly exhibited heterogeneously low signal intensity on T 1WI Atypical epidermoid tumors had high signal intensity on T 1WI, the high concentration of protein but not the concentration of cholesterol and triglycerides seemed to be responsible for it