, ,

(1.Department of Radiology, Peking University Third Hospital, Beijing 100191， China; 2.CT/MRI Division,Affiliated Hospital of Hebei University, Baoding 071000, China; 3. Department of Radiology,Chengde Central Hospital, Chengde 067000, China)

MRI features and differential diagnosis of spinal epidural angiolipomas

ZHOUHuan1,2,XUHongwei3,YUANHuishu1*

(1.DepartmentofRadiology,PekingUniversityThirdHospital,Beijing100191，China; 2.CT/MRIDivision,AffiliatedHospitalofHebeiUniversity,Baoding071000,China; 3.DepartmentofRadiology,ChengdeCentralHospital,Chengde067000,China)

Objective To investigate the MRI features of spinal epidural angiolipomas. Methods Clinical and MRI data of 18 patients with spinal epidural angiolipomas confirmed pathologically were retrospective analyzed. The MRI features of lesion site, size, shape, signal, bone destruction, enhancement and typing were observed and analyzed. Results One case of 18 cases were located in cervical vertebra, 15 cases were thoracic vertebra, and 2 cases were lumbar vertebra. Ten cases formed paravertebral lump through foramen intervertebrale and damaged adjacent bones. MRI showed that T1W1 signal intensity was either isointense (n=11), mixed intense (n=5) or hyperintense (n=2). T2WI showed signal intensity was hyperintense (n=13) or mixed intense (n=5). The fat signal was seen in 5 cases, both T1W1 and T2W1 showed hyperintense. All the 18 cases showed remarkable enhancement. Ⅰ type (lesions confined to the spinal canal) was 8 cases (8/18, 44.44%), Ⅱ type (lesions were dumbbell-shaped to the spinal canal) was 10 cases (10/18, 55.56%). Conclusion The location of occurrence and the manifestations of MRI in spinal epidural angiolipomas have certain characteristics, which provides important clues to the preoperative diagnosis.

Spinal neoplasms; Angiolipoma; Magnetic resonance imaging

椎管内硬膜外血管脂肪瘤是一种罕见的良性肿瘤，主要由成熟的脂肪细胞、血窦、毛细血管、小血管共同组成;其发病率约占所有椎管肿瘤的0.14%～1.20%，占硬膜外肿瘤的2%～3%[1-3]。虽然其为良性肿瘤，但肿瘤较大时压迫脊髓或硬膜囊，甚至可破坏相邻骨质，引发一系列神经系统或局部疼痛等症状，因此及早发现、准确诊断该病具有重要的临床意义。笔者回顾性分析18例经手术病理证实的椎管内硬膜外血管脂肪瘤的MRI表现，并复习相关文献，旨在提高对该病的认识。

1 资料与方法

1.1 一般资料 回顾性分析我院2011年10月—2016年10月经病理证实的椎管内硬膜外血管脂肪瘤18例患者的临床和影像资料，其中男8例，女10例，年龄37～74岁，平均(56.5±10.3)岁。患者主要表现为胸背疼痛5例，受累脊髓平面以下感觉减退12例，瘫痪1例。患者均行MR平扫和增强扫描。

1.2 仪器与方法 采用GE Discovery MR 750 3.0T超导型MR扫描仪和CTL联合线圈。扫描时患者取仰卧位，MR平扫序列包括矢状位FSE T1WI，TR 473 ms，TE 8.3 ms；FSE T2WI，TR 2 850 ms，TE 120 ms；T2WI脂肪抑制IDEAL(iterative dixon water-fat separation with echo asymmetry and least-squares estimation)序列，TR 3 000 ms，TE 102 ms，FOV 38 cm×38 cm。轴位FRFSE T2WI，TR 4 337 ms，TE 120 ms，FOV 20 cm×20 cm，层厚3.0 mm，层间距0.5 mm。MRI增强经肘静脉手推注射对比剂Gd-DTPA，剂量0.2 mmol/kg体质量，流率2 ml/s，行轴位T1WI IDEAL序列(TR 706 ms，TE 9.9 ms)、冠状位(TR 483 ms，TE 11.2 ms)及矢状位(TR 761 ms，TE 11.2 ms)扫描，层厚3.0 mm，层间距0.5 mm。

1.3 图像分析 由2名具有10年以上脊柱病变诊断经验的放射科医师分别采用盲法独立阅片，意见不同时协商达成一致。根据Si等[4]提出的分型标准，将椎管内硬膜外血管脂肪瘤依据其生长形态及范围分为Ⅰ型[局限于椎管内；依据肿瘤是否含有脂肪成分又分为ⅠA型(无脂肪组织增生)和ⅠB型(脂肪组织增生)]，及Ⅱ型(哑铃状突至椎管外)。观察病变部位、肿块大小、形态、信号、骨质破坏情况、增强特点及分型。……