眶颅沟通性郎格尔汉斯细胞组织细胞增生症CT及MRI诊断

目的探讨眶颅沟通性郎格尔汉斯细胞组织细胞增生症CT及MRI表现，提高其诊断准确性。资料与方法回顾性分析经组织学证实的15例单发眶颅沟通性郎格尔汉斯细胞组织细胞增生症影像学资料。结果15例均发生于眼眶外、上壁交界处（额骨），其中左侧6例，右侧9例。CT表现：均呈溶骨性破坏，形成三角形骨质缺损区，边缘清楚但无硬化，伴密度不均匀的软组织肿块。MRI表现：T1WI呈低信号11例（与脑实质比较，以下同）．中等信号4例；T2WI呈高信号6例，等信号9例，但信号不均匀。CT及MRI增强后，病变显示中到重度强化。病变压迫颅内及眶内结构，8例浸润额、颞头皮软组织及颞肌，MRI显示额部脑膜增厚并强化7例。结论CT是眶颅沟通性郎格尔汉斯细胞组织细胞增生症诊断和鉴别的主要影像学检查方法；MRI可更清楚、准确地显示病变的范围，为治疗提供可靠依据，可作为一种补充的影像学检查方法。

CT and MRI Diagnosis of Langerhans' Cell Histiocytosis in Orbital Cranial Communicating Region

Objective To investigate the CT and MRI findings of Langerhans' cell histiocytosis in orbital-cranial communicating region so as to improve the diagnostic accuracy.Materials and Methods The imaging data of 15 cases with Langerhans' cell histiocytosis verified by histopathology were analyzed retrospectively.Results All the lesions were located in superolateral wall of the orbit(frontal bone).6 lesions occurred in left frontal bone and 9 lesions occurred in right frontal bone.On CT,triangular bone destruction with heterogeneous soft tissue mass in superolateral wall of the orbit was found.The lesions revealed clear margin without sclerosis.On MR,the lesions showed signal hypointensity compared to brain in 11 cases on T_1W and signal isointensity in 4 cases, the lesions demonstrated heterogeneous signal hyperintensity in 6 cases and signal isointensity in 9 cases on T_2W.Enhanced CT and MR imaging demonstrated moderate to marked enhancement.The lesions compressed the adjacent structures of cranial and orbital regions.8 cases infiltrated abutting frontal temporal scalp and temporal muscle.On MR imaging,frontal meninges thickening and enhancement were found in 7 cases.Conclusion CT is the first modality in diagnosis of Langerhans' cell histiocytosis in orbital cranial communicating region,MRI can demonstrate optimally the invading extent and provide more information for therapy as a complement imaging method.