【摘要】目的:通过对共同性斜视患者眼外肌的病理学研究,了解其发病机制及手术时机。方法:用光学显微镜和电子显微镜对56例共同性斜视的眼外肌进行观察。结果:斜视患者弱侧眼肌不同程度萎缩变性, 肌原纤维稀疏, H 带不清, 肌原纤维排列方向紊乱, 线粒体多, 嵴密, 肌质网扩张, 有些有髓神经髓鞘层次不清, 轴突水肿, 随病程延长, 肌纤维病变加剧。结论:共同性斜视患者斜视弱侧眼肌在结构上有明显的病理性改变,萎缩变性是产生共同性斜视的重要原因。斜视患者应尽早行手术治疗。
【关键词】 共同性斜视;眼外肌;病理
Pathological changes of extraocular muscles in concomitant strabismus
Ying Luan, ShuXia Wang, Bin Liu, BoYan Zhou, LiNa Zhou
Department of Ophthalmology, Peoples Hospital of Jilin Province, Changchun 130021, Jilin Province, China
Correspondence to: Ying Luan. Department of Ophthalmology, Peoples Hospital of Jilin Province, Changchun 130021, Jilin Province, China. [email protected]
AbstractAIM: To investigate the mechanism and the best operation time for concomitant strabismus by studying the pathological changes of extraocular muscles.METHODS: The pathological ultrastructure of extraocular muscles was observed with light and electron microscope in 56 specimens of concomitant strabismus.RESULTS: The muscle fibers of weaker ocular muscle atrophied or degenerated to different extent and myofibrils became thinly scattered. H band was not clear. Arrangement direction of myofibrils were in disorder. There were many mitochondria and mitochondrion crista became thick. Sarcoplasmic reticulum was enlarged. Levels of myelin sheath were confused in some medullated nerves. Axons became edematous. The pathological change of myofibers became more obvious with the prolongation of the course. Parts of stronger ocular muscle had slight degeneration. CONCLUSION: Remarkable pathological changes of structure existed in weaker ocular muscles of concomitant strabismus patients. Atrophy and degeneration were important causes for concomitant strabismus. Strabismus patients should have surgical treatment early. KEYWORDS: concomitant strabismus; extraocular muscle; pathology
引言
共同性斜视确切的发病机制还不甚明了,我们对56例斜视矫正术中切取弱侧眼内、外直肌进行光镜和电镜观察,旨在探讨共同性斜视发病的病理学基础,并能用之指导斜视治疗时机及治疗方案的选择。
1对象和方法
1.1对象
本组56例共同性斜视中,外斜34例,内斜22例;男30例,女26例;年龄7~40(平均13.4)岁;病程 5~32a;斜视度45△~140△;所有病例第一斜视角和第二斜视角相等,无眼球运动障碍,无垂直非共同性。术前常规作体检及视力、屈光状态、外眼、眼底等检查以排除其它眼病,进行同视机、三棱镜加遮盖及视功能检查,根据检查数据设计手术量。正常对照组2例(2眼):1例1眼,男52岁,绝对期青光眼行眼球摘除术;1例1眼,女35岁,外伤致眼球破裂。分别取内、外直肌组织为对照标本。
1.2方法
斜视矫正术中行弱侧眼肌缩短时将切除的眼外肌标本,其中内直肌34例,外直肌22例;正常人内、外直肌标本各2例。将每例标本1/2用40g/L甲醛溶液固定,石蜡包埋,HE染色;1/2置于30g/L戊二醛磷酸盐缓冲液中,4℃冰箱内固定24h以上,行磷酸盐缓冲液冲洗,10g/L四氧化锇再固定2h,酒精逐级脱水,环氧树脂包埋,半超薄切片,甲苯胺蓝染色,光镜观察、定位;取适当部位做超薄切片,醋酸铀枸橼酸铅双重染色,电镜下观察。
2结果
2.1光镜
对照组的2例内、外直肌在光镜下可见肌肉纤维排列较紧密、整齐、方向一致、肌纤维间质成分较少(图1)。斜视组斜视弱侧肌肉,大部分均表现为肌纤维排列疏松,肌纤维较少,方向不一致,间质成分多。在两个不同年龄组,大龄组中有的未见肌纤维,可见大量胶原组织。有些肌纤维极少,排列紊乱、疏松,间隙变大,胶原增多(图2)。
2.2电镜
对照组的眼外肌细胞膜完整,肌原纤维排列整齐、紧密、肌节整齐,明、暗带及Z线、H带结构清晰、线粒体分布均匀、含少量糖元(图3)。 斜视眼弱侧眼肌均有不同程度的病变,主要表现为肌细胞萎缩、退变或发育不良改变,重者肌细胞坏死消失,代之以纤维组织。具体表现为多数肌纤维体积变小,肌膜不完整,有大量肌膜下包涵物,肌丝成分变少致质膜塌陷皱缩;局灶节段性肌丝排列紊乱较多,有的区域肌丝溶解消失或肌丝排列稀疏,肌节不明显或Z线呈水纹状改变,H带结构不清;线粒体可轻度增多,大小形态不一致,嵴可增生呈同心圆排列或水肿断裂,有的肌细胞质膜下见成堆的线粒体;肌质网扩张较常见,肌核内移较明显;间质胶原纤维增生,成纤维细胞较多见,弹力纤维较少见,有髓或无髓神经纤维均可见,但数量减少,有些髓鞘层次结构不明显,轴突轻度水肿,神经肌接头处突触小泡丰富,突触间隙较宽。总之,肌细胞病变较明显,呈慢性损害改变,以肌丝排列紊乱、肌核内移及线粒体异常为主。随病程延长斜视度增大,肌纤维病变加剧,有些病例肌纤维几乎全部退化为纤维组织(图46)。
[1] [2] 下一页 |