眼眶原发淋巴瘤CT、MRI表现及文献复习(附7例报告)

目的:研究眼眶原发淋巴瘤CT、MRI表现,提高对该病的诊断能力。方法:7例经病理证实的眼眶原发淋巴瘤患者均经CT平扫增强和延迟扫描,其中3例行MRI平扫加增强扫描。回顾性分析CT及MR的影像学表现。结果:双侧眼眶原发淋巴瘤2例,分别位于双侧结膜和泪腺。单侧眼眶淋巴瘤5例。1例位于泪道;另4例跨越眶隔前后部呈不规则铸型累及泪腺及泪道,其中3例浸润肌锥内外间隙。所有病例均未见眼外肌推压移位、眼环增厚与变形。2例可见眶骨明显骨质破坏。所有病变CT平扫呈软组织肿块,密度类似于眼外肌,边缘清晰,增强后,4例呈中度强化,3例呈轻度强化,延迟期中度强化4例密度下降,轻度强化3例无明显变化。MRI上3例肿块在T1WI和T2WI上与眼外肌信号相比,呈等信号,增强后2例病变信号强度高于眼外肌。所有病变在CT、MRI上均呈匀质性。结论:眼眶原发淋巴瘤CT、MRI表现具有一定的特征性,能够高度提示该病的诊断。

CT and MRI findings of primary orbital lymphoma and review of literature(report of 7 cases)

Objective:To study CT and MRI findings of primary orbital lymphoma, to improve the diagnostic ability of this disease. Methods:Plain CT, enhanced CT and delayed CT scans were performed in all 7 patients with primary orbital lymphoma proved histopathologically. In 3 of the 7 patients, the plain and enhanced MRI were performed. Both CT and MRI findings were analyzed retrospectively. Results:Bilateral lesions were found in 2 patients, located in bilateral conjunctivae and lacrimal gland respectively. Unilateral lesion was found in 5 patients. The lesion located in lacrimal duct in 1 patient, in the other 4 patients the lesion crossed orbital septum and molded around orbital structures with irregular shape, and the lacrimal gland and lacrimal duct were involved, in 3 of the 4 patients the diffuse lesion infiltrated extraconal and intraconal space. There were no displacement of extraocular muscle, thickening and deformity of ocular ring in all patients. Destruction of orbital bone was evident in 2 patients. All the lesions presented soft tissue density similar to extraocular muscle and with distinct margin on plain CT scan, the density of lesion which showed mild enhancement on enhanced CT in 4 patients was found to decrease on delayed phase, there was no obvious change of density in the other 3 patients on delayed CT scans, compared to enhanced CT. MRI findings in 3 patients demonstrated isointense signal compared to extraocular muscle on T1WI and T2WI. However, the lesion in 2 patients was hyperintense compared to extraocular muscle after enhancement. All the lesions showed homogeneous on CT and MRI. Conclusion:The CT and MRI findings of primary orbital lymphoma are characteristic, which can highly suggest the diagnosis of this disease.