先天性眼外肌纤维化综合征MR成像分析

目的通过观察先天性眼外肌纤维化（CFEOM）三种临床表型的眼运动神经和眼外肌及周围组织的影像学特征，为本病的病因学研究提供线索。设计回顾性病例系列。研究对象CFEOM患者21例。方法对21例CFEOM患者行全脑、脑干、海绵窦及眼眶的MRI扫描。全脑平扫；眼运动神经脑池段，采用头颅线圈，层厚0．8mm，重T2加权，三维FIESTA序列扫描；眼运动神经海绵窦段，采用头颅线圈，层厚2mm，T1加权像扫描；眼外肌和眼运动神经的眶内段，采用表面线圈，层厚2mm，T1加权像扫描。显示脑池段的眼球运动神经、眶内各神经分支和眼外肌。主要指标眼球运动神经分布和眼外肌的发育情况。结果CFEOM患者的动眼神经、外展神经及滑车神经的眶内段和脑池段均表现出不同程度的发育不良。六条眼外肌均表现不同程度萎缩，以上直肌和提上睑肌最为严重，上斜肌和外直肌改变轻微。结论CFEOM患者眼运动神经和眼外肌结构均发育不良。特别是脑池段运动神经发育不良的影像学特征明确，提示CFEOM的原发病变是运动神经发育缺陷。

Abnormalities of motor nerves and extraocular muscles in congenital fibrosis of extraocular muscles demonstrated by high-resolution magnetic resonance imaging

Objective To investigate the structural basis of three types of congenital fibrosis of extraocular muscles （CFEOM） by high-resolution magnetic resonance （HR-MR） images and try to provide the etiological clue of CFEOM. Design Retrospective case series. Participants Twenty-one CFEOM patients. Methods Twenty-one CFEOM patients were performed MR examination on 1.ST MR unit （Twin Speed, GE）. EOMs and the motor nerve branches in the orbits were displayed on T1 weighted image （2.0-mm thick） in triplanar scans by dual-phased coils. Ocular motor nerves were imaged in the cistern on 3D-FIESTA （0.8-mm thick） by head coils. Ocular motor nerves, nerves to EOMs and EOMs were observed. Main Outcome Measures The developmental condition of the ocular motor nerves and EOMs. Results Different degree of hypoplasia of oculomotor nerve was exhibited in patients with three types of CFEOM, and the abducens nerve and the trochlear nerve were also affected. Nearly every EOM was exhibited variable atrophy and abnormal brightness on T1 weighted image, particularly severe in superior rectus and levator muscles. Conclusion HR-MR imaging can directly demonstrate pathology of ocular motor nerves and affected EOM hypoplasia in CFEOM patients, especially the obvious hypoplasia of the ocular motor nerves which suggest that the neuronal hypoplasia is the etiological factor of CFEOM.