眶内炎性假瘤MRI分析

目的：探讨眶内炎性假瘤的MRI影像特征及鉴别诊断。方法回顾性分析48例眶内炎性假瘤的MRI平扫及其增强扫描的影像学特征，均为手术病理或随访结果证实。结果48例炎性假瘤根据影像学表现分为四型：①肿块型，表现为边界清楚的软组织肿块，位于肌锥内；②弥漫炎症型，眶内被病灶填充，边界模糊，眼直肌与病灶分界不清，视神经被包绕，压脂增强扫描T1 WI显示视神经不强化；③泪腺炎型，表现为泪腺增大，T1 WI信号稍低、T2 WI呈中等信号，压脂序列呈稍高信号；④肌炎型，眼外肌不同程度增粗，主要累及上直肌和内直肌。结论 MRI能清楚显示眶内炎性假瘤的信号特征、大小、形态与邻近结构的关系，因此对眶内炎性假瘤能够做出定位、定性诊断。

MRI analysis of orbital inflammatory pseudotumor

Objective To explore the orbital inflammatory pseudotumor of the imaging features and differential diagnosis of the MRI. Methods MRI scan and enhanced scan image features of 48 cases of orbital inflammatory pseudotumor were retrospec-tively analyzed,and all of them were diagnosed by the surgical pathology or follow-up the results. Results Forty-eight cases of inflammatory pseudotumor were divided into four types based on imaging findings：①mass type,shows the boundary clear soft tissue mass,located in the muscle cone;②diffuse inflammation type,orbital is filled with lesions,fuzzy boundaries,eye rectus muscle is no clear boundary between lesions and optic wrapped around,fat suppression T1WI enhancement scanning display optic reinforcement;③ dacryoadenitis type,characterized by lachrymal increase,slightly lower,T2WI moderate T1WI signal,pres-sure fat sequence was slightly higher signal;④myositis type,extraocular muscle enlargement of different level,mainly involving the rectus muscle and medial rectus muscle. Conclusion MRI can clearly show the signal features of orbital inflammatory pseudotumor,size,shape,and the relationship between adjacent structure,thus to make positioning of orbital inflammatory pseudotumor and qualitative diagnosis.