眼眶原发性淋巴瘤的MRI表现

目的：探讨眼眶原发性淋巴瘤的磁共振影像学表现，以提高其诊断的准确率。方法对11例经手术病理证实的原发性淋巴瘤的临床和影像学资料进行回顾性分析。结果眼眶原发性淋巴瘤的MRI特征如下：①好发于隔前眶周，以眼眶外上象限为主，包括眼睑、泪腺、结膜等；②无包膜，沿眼眶间隙蔓延塑形生长；③平扫T1WI呈等信号，T2WI呈稍高信号，增强呈中-重度强化；④DWI上表现为高信号；⑤边界较清晰，对周围组织结构侵犯、破坏少见；⑥囊变少见，出血、钙化罕见。结论眼眶原发性淋巴瘤MRI表现具有一定的特征性，MRI多方位成像可对肿瘤明确定位，并有助于定性诊断。

MRI appearances of primary orbital lymphoma

Objective To study MRI appearances of primary orbital lymphoma in order to improve diagnostic accuracy of the disease .Methods Clinical data and MRI findings of 11 patients with pathologically proved primary orbital lymphoma observed from January 2007 to June 2013 were analyzed retrospectively .Results The characteristics of the tumor were that：① mostly located in extraconal and upper-before of the orbital septum ,inclined to upper-outside lateral quadrant of the orbit include eyelid ,lacrimal gland and conjunctiva ,etc;② no envelope and the tumor infiltrated intraorbital tissues a-long with extra ocular muscles;③ on MRI ,the lesion showed iso-tensity on T1WI and slight hypertensity on T2WI and the degree of enhancement inferior to extra ocular muscles with enhancement scanning ;④ all cases showed hyper-intensity on DWI;⑤ most tumors’ boundary were clearly and rare invaded of destructed adjacent structures ;and ⑥ cyst was relative-ly infrequent and hemorrhage and calcification were very rare .Conclusion The MRI appearances of primary orbital lym-phoma possess unique characteristics and multi-direction imaginges are helpful for making a correct diagnosis .