原发性开角型青光眼非穿透小梁手术患者深层巩膜瓣及小梁膜的病理学观察

Pathological study on the deep scleral flap and external trabecular membrane obtained from non-penetrating trabecular surgery

目的 研究原发性开角型青光眼患者 (POAG)非穿透小梁手术的解剖学基础 ,探讨POAG患者房水外流的阻力部位及其病理改变。方法 选择行非穿透小梁手术的POAG患者 12例(18只眼 ) ,取术中切除的深层巩膜瓣及撕除的外层小梁膜进行光镜、扫描电镜及透射电镜观察。结果 光镜观察标本见 :深层巩膜瓣前端为少许深层角膜基质 ,并可见Schlemm管外壁单层内皮细胞。扫描电镜观察见 :深层巩膜瓣内侧可见被打开的Schlemm管管腔和狭长的积液管开口 ;撕除膜小梁面可见角巩膜小梁的网状结构 ,排列致密 ,网眼较小 ,近管腔侧呈致密的板状结构。透射电镜观察见 :Schlemm管外壁周围散在高电子密度物质 ;撕除膜包括Schlemm管内壁 ,邻管组织 (内皮网 )和部分角巩膜小梁 ,邻管组织细胞减少 ,细胞外基质增多 ,可见大量致密斑块沉积 ;角巩膜小梁网胶原板层结构增厚 ,弹力纤维增多 ,细胞体积增大 ,尤以细胞核增大明显。晚期患者的角巩膜小梁网内有致密斑块沉积 ,阻塞了小梁间隙。结论 非穿透小梁手术的深层巩膜瓣包括Schlemm管外壁 ,撕除膜包括邻管组织和部分角巩膜小梁。邻管组织和部分角巩膜小梁是POAG患者房水外流的主要阻力部位 ,同时Schlemm管外壁也是其重要构成部分。

Objective To study the anatomic background of non-penetrating trabecular surgery (NPTS) and to explore the resistant site of aqueous outflow in primary open-angle glaucoma. Methods NPTS was performed in 18 eyes of 12 cases (10 males, 2 females) with POAG. The age of these patients ranged from 42 to 65 years old. The deep scleral flap and external trabecular membrane were obtained during the surgical procedure and were examined by light microscope, scanning electron microscope (SEM) and transmission electron microscope (TEM). Results The beginning part of the collection canal in the outer wall of the Schlemm′s canal were very narrow, and there was electron dense material (so-called plaques) around the outer wall of the Schlemm′s canal. The external trabecular membrane consisted of adjacent trabecular meshwork and part of the corneoscleral trabecular meshwork. The number of the trabecular cells was decreased and a large amount of electron dense materials were deposited in the adjacent trabecular meshwork. The holes of the corneoscleral trabecular meshwork was small and irregular. In the corneoscleral trabecular meshwork, the trabecular lamellae was thicken, the amount of elastic-like fibers was increased and the trabecular cells, especially the nucleus, were enlarged. In the advanced stage of POAG, a great amount of electron dense material was deposited in the corneoscleral trabecular meshwork and the inter-trabecular spaces was blocked. Conclusions The deep scleral flap of NPTS contains the outer wall of Schlemm′s canal and the external trabecular membrane, which consists of the inner wall of the Schlemm′s canal, the adjacent trabecular meshwork and part of the corneoscleral trabecular meshwork. The main resistant site of aqueous outflow in POAG lies in the adjacent trabecular meshwork and in part of the corneoscleral trabecular meshwork. The outer wall of the Schlemm′s canal is another important resistant site for aqueous outflow.