Mohamed Yasser Helmy, Uematsu Masafumi, Kusano Mao, Kitaoka Takashi, Nishida Teruo
Department of Ophthalmology and Visual Sciences, Graduate School of Biomedical Sciences, Nagasaki University, 1-7-1 Sakamoto, Nagasaki, Nagasaki, 852-8501, Japan.
Department of Ophthalmology, Graduate School of Medicine, Yamaguchi University, Ube, Yamaguchi, Japan.
Med Mol Morphol. 2025 Mar;58(1):69-74. doi: 10.1007/s00795-024-00405-z. Epub 2024 Oct 1.
The aim of this study was to report transmission electron microscopic findings of a case with whole corneal descemetocele following infective corneal ulcer for the first time in literature. A 72-year-old male patient presented with infective corneal ulcer. After resolution of the infection, corneoscleral transplantation was performed. The excised very thin corneal membrane was processed for transmission electron microscopic examination. Transmission electron microscopic examination of the specimen revealed many layered structures that consisted of two different types of cells. The first type consisted of lighter staining polygonal cells, while the second consisted of elongated cells with relatively dense staining. All cells were connected with a large number of gap or adherens junctions with intercalation of the cell membranes of adjacent cells. A haphazard distribution of cytoplasmic microfilaments were also observed in all of the cell types. There was no evidence of the presence of endothelial cells throughout the specimen. There was also no evidence of Descemet membrane presence except for a small part adjacent to iris tissue that contained some melanosomes. Although we clinically diagnosed descemetocele, Descemet membrane was not present at the electron microscopic level, and thus, the expression "descemetocele" is inappropriate.
本研究的目的是首次在文献中报告一例感染性角膜溃疡后全角膜后弹力层膨出病例的透射电子显微镜检查结果。一名72岁男性患者出现感染性角膜溃疡。感染消退后,进行了角巩膜移植。将切除的极薄角膜膜进行透射电子显微镜检查。对标本的透射电子显微镜检查显示出许多由两种不同类型细胞组成的分层结构。第一种类型由染色较浅的多边形细胞组成,而第二种类型由染色相对较深的细长细胞组成。所有细胞通过大量间隙连接或黏着连接相连,相邻细胞的细胞膜相互交错。在所有细胞类型中还观察到细胞质微丝的随机分布。在整个标本中均未发现内皮细胞存在的证据。除了与虹膜组织相邻的一小部分含有一些黑素体之外,也没有发现后弹力膜存在的证据。尽管我们临床诊断为后弹力层膨出,但在电子显微镜水平上未发现后弹力膜,因此,“后弹力层膨出”这一表述并不恰当。