Orellana J, O'Malley R E, McPherson A R, Font R L
Ophthalmology. 1985 Feb;92(2):297-302. doi: 10.1016/s0161-6420(85)34042-3.
Pigmented free-floating vitreous cysts were observed in two young adults. In both patients, the cyst was in the visual axis; however, the size and extent of pigmentation of the cyst wall compromised the visual acuity only in case 1. In this case, the vitreous cyst was aspirated through the pars plana and studied by light and electron microscopy. Histopathologically, the cyst was lined by a heavily pigmented layer of cuboidal cells intermixed with sheets of nonpigmented cells forming papillae. Ultrastructurally, the pigmented cells contained predominantly large, mature melanosomes (0.9-2.2 micron). Scattered immature melanosomes with a scarcity of mitochondria and other cytoplasmic organelles were present. Additionally, the cells were invested by a thin polarized basement membrane and displayed apical microvilli. Numerous microvillous processes were noted under the plasmalemmae and between adjacent cells. The results of the light and ultrastructural studies provide support for the hypothesis that the cyst in case 1 originated from the pigment epithelium. The possibility of a traumatic etiology is proposed for these pigmented vitreous cysts. If significant visual impairment is present, surgical removal of the cyst through a pars plana approach can be safely performed as in our case 1.
在两名年轻成年人中观察到色素性游离玻璃体囊肿。在这两名患者中，囊肿均位于视轴；然而，仅病例1中囊肿壁的色素沉着大小和范围影响了视力。在该病例中，通过睫状体扁平部抽吸玻璃体囊肿，并进行光镜和电镜研究。组织病理学上，囊肿内衬一层色素沉着严重的立方体细胞，其间夹杂着形成乳头的无色素细胞片。超微结构上，色素细胞主要含有大的成熟黑素小体（0.9 - 2.2微米）。存在散在的未成熟黑素小体，线粒体和其他细胞质细胞器较少。此外，细胞被一层薄的极化基底膜包绕，并显示顶端微绒毛。在质膜下和相邻细胞之间可见许多微绒毛样突起。光镜和超微结构研究结果支持病例1中的囊肿起源于色素上皮的假说。对于这些色素性玻璃体囊肿，提出了创伤性病因的可能性。如果存在明显的视力损害，如我们的病例1那样，通过睫状体扁平部入路安全地进行囊肿手术切除是可行的。
