间歇性外斜视患者眼外肌的超微结构研究

摘要

目的 研究间歇性外斜视患者眼外肌的超微结构,以期探讨间歇性外斜视的发病机制.方法 取8例间歇性外斜视患者、8例恒定性外斜视患者(间歇性外斜视恒定化)及8例同期角膜移植供体的健康人眼内直肌,常规HE染色后在光镜下观察并计算每例标本每100倍视野下肌纤维的含量;利用透射电镜观察8例间歇性外斜视患者与5例同期角膜移植供体的健康人眼内直肌的超微结构.结果光镜下正常对照组眼外肌纤维分布均匀,大小、形态正常,排列规则整齐.间歇性外斜视及恒定性外斜视患者眼外肌纤维大小不一、形态异常,数量减少,排列紊乱,每例标本100倍视野肌纤维含量明显少于正常对照组(P<0.05),其中恒定性外斜视患者肌纤维含量明显少于间歇性外斜视组(P<0.05).透射电镜下可见间歇性外斜视患者眼外肌纤维萎缩、水肿、肌丝变少,排列紊乱,线粒体变性,严重者可见肌纤维坏死、胶原纤维增生.结论 间歇性外斜视患者弱侧眼外肌内直肌发生了病理性改变,可能与间歇性外斜视病因及发病机制有关.%Objective To ohserve the ultrastructure of extraocular muscle ( EOM ) in intermittent exotropia and discuss its pathothogenesis. Methods Samples obtained from medial rectus of 8 patients intermittent exotropia, 8 patients with constrant exotropia, and 8 corneal donors , were stained with HE, and then examined under light microscopy( LM ) to observe the structure of extraocular muscle and count the number of the muscle fibers of each sample under 100 × magnification;8 case of sample from medial rectus of patients with intermittent exotropia and 5 samles of medial rectus from corneal graft donors were studied under transmission electron microscopy( TEM ). Results ( 1 )Under light microscopy, the muscle fibers of medial rectus of patients with intermittent exotropia and constrant exotropia showed atrophied and myofibribs became thin. Arrangmental direction of myofibrils became disorder. The numer of the muscle fibers under 100 × magnification of the groups with intermittent exotropia and constrant exotropia was significantly fewer than that in the control group( P＜ 0. 05 ),and the number of the groups with intermittent exotropia was significantly fewer than in the constrant exotropia( P ＜0. 05 ). Conclusion The pathologic abnormality was been found in the ultrastructure of extraocular muscle with intermittent exotropia, which could be a possihle etiology and pathogenesis of intermittent exotropia.