眼眶肿瘤及瘤样病变的MRI影像学表现

MRI features of orbital tumors and tumor-like lesions

目的总结眼眶肿瘤及类肿瘤病变的MRI特点,探讨其诊断思路。方法回顾性分析2008-2013年海南医学院第一附属医院收治且经手术病理证实的35例眼眶肿瘤的MRI表现,归纳总结每种病变的好发部位、形态、边界、信号特点及强化方式,并结合文献找出疾病的具有诊断价值的影像学共同特征。结果本组35例眼眶肿瘤中,泪腺区肿瘤6例,包括多形性腺瘤4例及腺样囊性癌2例,呈等T1稍长T2信号,增强后中度-明显强化。视神经鞘膜脑膜瘤3例,呈等T1等T2信号,增强中度-明显强化。血管类病变10例,包括海绵状血管瘤9例及静脉畸形1例,海绵状血管瘤呈长T1长T2信号,增强明显强化。神经鞘瘤4例,3例合并囊变,呈长T1长T2信号,增强后实性成分明显强化。淋巴瘤5例,呈等T1等T2信号,增强后轻-中度强化。皮样囊肿1例,短或等T1、长T2信号,增强无强化。骨膜下脓肿1例,增强环形强化。神经纤维瘤、纤维肉瘤各1例,信号呈等或稍长T1、等或长T2信号,增强明显强化。炎性假瘤3例,呈等T1等T2信号,增强后中度-明显强化。结论 MRI可清晰显示肿瘤的大小、形态、内部结构及与周围组织的关系,对眼眶肿瘤及瘤样病变的定位、定量及定性诊断有较大的价值,可提供较好的诊断思路。

Objective To summary and analyze the MRI features of orbital tumor and tumor-like lesions, andto explore its diagnostic strategy. Methods Thirty-five cases of orbital tumors confirmed by surgery pathology in theFirst Affiliated Hospital of Hainan Medical College from 2008 to 2013 were retrospectively reviewed for MRI manifesta-tion. The location, shape, boundary, signal characteristics, enhancement methods of each disease were summarized, andthe common imaging features were analyzed on the basis of literature. Results Among the 35 cases of orbital tumors,there were 6 cases of lacrimal gland tumor, including 4 cases of pleomorphic adenoma and 2 cases of adenoid cystic car-cinoma, showing equal T1 and slightly long T2 signal on MRI, with moderate to significant enhancement. There were 3cases of optic nerve sheath meningioma, showing equal T1 and equal T2 signal on MRI, with moderate to significant en-hancement. There were 10 cases of vascular lesions, including 9 cases of cavernous hemangioma and 1 case of venousmalformations, and the cavernous hemangioma showed long T1 and long T2 signal on MRI, with significant enhance-ment. The 4 cases of schwannoma, among which 3 cases were complicated with cystic lesions, showed long T1 and longT2 signal on MRI, with the solid portion of mass enhanced obviously. The 5 cases of lymphoma showed equal T1 andequal T2 signal on MRI, with light to moderate enhancement. The one case of dermoid cyst showed short or equal T1and long T2 signal on MRI, without enhancement. The one case of subperiosteal abscess showed annular enhancement.There were 1 case of neurofibroma and 1 case of fibroma sarcomatosum, showing equal or slightly long T1 and equal orlong T2 signals on MRI, with significant enhancement. Inflammatory pseudotumor （3 cases） showed equal T1 and equalT2 signal on MRI, with moderate to significant enhancement. Conclusion MRI can clearly show tumor size, shape, in-ternal structure and the relationship with the surrounding tissue, which has high value in the localization, the quantitativeand qualitative diagnosis of orbital tumor and tumor-like lesions, and thus provide better diagnosis strategy.