椎管内皮样囊肿破入脊髓中央管的MRI诊断

MRI diagnosis of intraspinal dermoid ruptured into central spinal canal

目的探讨椎管内皮样囊肿破入脊髓中央管的MRI表现及其诊断和鉴别诊断。方法回顾性分析11例椎管内皮样囊肿破入脊髓中央管的影像和临床资料。6例患者行全脊柱MR扫描，2例行胸、腰椎MR扫描，3例仅行腰椎MR扫描。结果破入脊髓中央管的游离脂滴在T1WI上呈高信号，T2WI上信号略有衰减，脂肪抑制序列呈极低信号。所有11例患者中，2例破入邻近脊髓中央管，3例见散在游离脂滴分布于胸段脊髓中央管，4例断续分布于全程脊髓中央管，2例呈局限性连续带状分布。结论皮样囊肿破入脊髓中央管的MRI表现具有特异性，当MRI显示腰骶段椎管内皮样囊肿时，应行全脊柱MR扫描，以除外皮样囊肿破裂脂滴进入脊髓中央管的可能性。

Objective To evaluate the appearances of intraspinal dermoid ruptured into the central spinal canal, as well as the MRI diagnosis and differential diagnosis. Methods Eleven cases of intraspinal dermoid ruptured into the central spinal canal were reviewed. Six cases underwent whole spine MRI scan, 2 cases with thoracic and lumbar spine MRI, as well as 3 cases only with lumbar spine MRI. Results Free fat droplets within spinal cord central canal demonstrated high signal intensity on T1WI, slight declined signal intensity on T2WI, and extremely low signal on fat suppression sequence. Of the 11 cases, 2 cases broke into neighboring central spinal canal of the dermoid, 3 cases scattered within thoracic spinal cord central canal, 4 cases discontinuously distributed in the whole spinal cord central canal, 2 cases showed continuous distribution. Conclusion Intraspinal dermoid ruptured in the central spinal canal had specific appearance on MRI, when a dermoid tumor is suspected, MRI of the entire spine were recommended to detect possible leakage of fat within central spinal canal.