眼眶淋巴瘤的CT和MR影像特点

目的:探讨眼眶淋巴瘤的CT和MR影像特点，为临床提供更多有价值的影像学信息。方法:　回顾性分析9例（共10眶）经病理诊断明确的眼眶淋巴瘤的CT及MR影像学表现，包括病变的位置、形态、密度及信号，强化方式及其与邻近结构的关系。 结果:　纳入10眶病例的临床表现主要以眼球突出、眼睑肿物为主；纳入10眶病变中跨越2个区域或以上的有7眶；7眶为弥漫型，3眶为局限型；CT密度以同层面眼外肌密度为参照均为均质稍高密度，增强扫描呈均质（1眶）或不均质（3眶）中等强化；MR同样以同层面眼外肌为参照，病变为均质T1WI呈等、稍低信号，T2WI呈稍高信号；眼外肌有两个或以上受累者有6眶。结论:　眼眶淋巴瘤影像学表现有一定的特征性，好发于眶隔前区及泪腺区，病变密度及信号均匀，增强扫描呈轻至中度强化，可以为临床诊断及治疗提供重要的参考价值。

Characteristics of CT and MR imaging of orbital lymphoma

Objective:To investigate the characteristics of CT and MR imaging of orbital lymphoma，and to provide more valuable imaging information for clinic.Methods:CT and MR imaging manifestations of 9 cases(10 orbits) with clear pathological diagnosis of orbital lymphoma were retrospectively analyzed，including the location，morphology，density and signal of the lesion，enhancement mode and its relationship with adjacent structures.Results:The clinical manifestations of the 10 orbits included were mainly eyeball protrusion and eyelid mass.Among the 10 orbital lesions，7 orbits spanned 2 regions or more.7 orbits were diffuse and 3 orbits localized.CT density was homogeneous and slightly high，with the same lateral ocular muscle density as the reference.Enhancement scans were homogeneous(1 orbits) or heterogeneous(3 orbits) with moderate enhancement.On MR，the same level of extraocular muscle was used as reference，and T1WI presented equal or slightly lower signal，while T2WI presented slightly higher signal.In 6 orbits，two or more extra-ocular muscles were involved.Conclusion:The imaging findings of orbital lymphoma were characteristic.Lymphoma tends to occur in the preorbital septal area and lacrimal gland area.The lesion density and signal are uniform，and the enhancement scan showed mild to moderate enhancement，which can provide important reference value for clinical diagnosis and treatment.