后天性外展神经麻痹的MRI病因学分析

 目的 探讨后天性外展神经麻痹的MRI表现，分析外展神经麻痹原因，为临床诊断、治疗提供依据。设计 回顾性病例系列。研究对象 42例后天性外展神经麻痹患者。方法 回顾性分析42例临床诊断证实的后天性外展神经麻痹患者的MRI表现，包括病变部位、范围、信号和强化特征，结合外展神经的解剖特点，分析神经麻痹的原因。主要指标 MRI表现。结果 缺血性外展神经麻痹16例，患者均有糖尿病、高血压或高脂血症等病史，MRI表现为颅内多发缺血灶、软化灶，老年性脑萎缩等。占位性病变15例，病变位于桥前池、岩尖和海绵窦，累及展神经脑池段、Dorello小管段和海绵窦段。外伤性外展神经麻痹5例，1例有右侧颅骨多发骨折，出现左侧外展神经麻痹症状，其余4例均无明确颅骨和眼眶骨折证据。非特异性炎症4例，3例表现为海绵窦偏前部增厚、强化。其他原因包括重症肌无力1例，桥小脑角区胆脂瘤术后1例。结论 MRI检查有助于明确外展神经麻痹的病因及发病部位，进而指导针对性治疗。（眼科，2013, 22： 305-308）

MRI features of acquired abducens nerve palsy

Objective To explore MRI features of acquired abducens nerve palsy to provide reliable imaging basis for clinical diagnosis and treatment. Design Retrospective case series. Participants Forty-two patients with acquired abducens nerve palsy. Methods The MRI of 42 cases with acquired abducens nerve palsy were analyzed retrospectively. The MRI features of lesions were observed, including location, morphology, extent, signal intensity and the characteristics of contrast. Main Outcome Mearsures MRI findings. Results Sixteen cases were diagnosed with ischemic abducens nerve palsy, the main findings of MRI was multiple ischemic focus in brain. Tumor was found in 15 patients and the main locations were at prepontine cistern, tip of petrous bone or cavernous sinus, with corresponding segments of abducens nerve afflicted. Five patients got acquired abducens nerve palsy after head trauma, including 1 case of left abducens nerve palsy after multiple fractures of right skull and 4 cases with no fracture in skull bones. Four patients were diagnosed with nonspecific inflammation, in which 3 cases were manifested as cavernous sinus thickening. Other rare causes included 1 case of myasthenia gravis and 1 case  who was after cerebellopontine cholesteatoma surgery. Conclusion The etiology of acquired abducens nerve palsy is quite diverse and MRI is useful to define the causes and original locations and help to guide specific treatment. (Ophthalmol CHN, 2013, 22: 305-308)