Mossa Elshimaa A Mateen, Sayed Khulood Muhammad, Mounir Amr, Ammar Hatem
Department of Ophthalmology, Sohag Faculty of Medicine, Sohag University, Sohag, Egypt.
Med Hypothesis Discov Innov Ophthalmol. 2022 Sep 23;11(2):85-91. doi: 10.51329/mehdiophthal1450. eCollection 2022 Summer.
Corneal endothelial cell (CEC) loss in glaucoma can be attributed to the direct compressive effect of elevated intraocular pressure. Herein, we aimed to evaluate specular microscopic changes in CEC count and morphology in correlation to retinal nerve fiber layer (RNFL) changes detected by spectral-domain optical coherence tomography (SD-OCT) in early and advanced primary open-angle glaucoma (POAG).
This descriptive-analytical study involved patients with medically controlled POAG versus non-glaucomatous patients of the same age group. Specular microscopy, visual field testing, and SD-OCT of the RNFL and macular ganglion cell complex (GCC) were performed. Eyes with POAG were further subcategorized into early and advanced stages.
The study included 130 eyes of 130 participants; 70 were eyes with POAG (40 eyes with early-stage POAG, 30 eyes with advanced-stage POAG), and 60 were healthy eyes. The groups were comparable regarding mean age and sex. No significant difference was found in corneal parameters between healthy eyes, eyes with early POAG, and eyes with advanced POAG (all > 0.05). In eyes with early-stage POAG, a significant negative correlation was found between the coefficient of variation (CV) and superior RNFL thickness (r = - 0.5; = 0.018), and between the percentage of hexagonal cells (hexagonality) and vertical cup-to-disc ratio (r = - 0.43; P = 0.035). A significant positive correlation was found between hexagonality and superior as well as inferior RNFL thickness (r = + 0.53; = 0.008 and r = + 0.50; = 0.015, respectively). However, in the advanced glaucomatous eyes, no significant correlation was found between RNFL thickness and CEC parameters.
CEC parameters were not affected in eyes with early or advanced POAG compared with healthy eyes, despite a significant thinning of RNFL and macular GCC. In eyes with early-stage POAG, a significant correlation was found between morphological characteristics of CECs, such as CV and hexagonality, with superior and inferior RNFL thickness in the optic nerve head on SD-OCT images. Future longitudinal studies with larger sample sizes are needed to verify our results.
青光眼患者角膜内皮细胞（CEC）的损失可归因于眼内压升高的直接压迫作用。在此，我们旨在评估原发性开角型青光眼（POAG）早期和晚期患者角膜内皮细胞计数和形态的镜面显微镜变化，及其与光谱域光学相干断层扫描（SD-OCT）检测到的视网膜神经纤维层（RNFL）变化之间的相关性。
本描述性分析研究纳入了药物控制的POAG患者和同年龄组的非青光眼患者。对患者进行了镜面显微镜检查、视野测试以及RNFL和黄斑神经节细胞复合体（GCC）的SD-OCT检查。POAG患者的眼睛进一步分为早期和晚期。
该研究纳入了130名参与者的130只眼睛；其中70只为POAG患者的眼睛（40只早期POAG眼睛，30只晚期POAG眼睛），60只为健康眼睛。两组在平均年龄和性别方面具有可比性。健康眼睛、早期POAG眼睛和晚期POAG眼睛之间的角膜参数无显著差异（均P>0.05）。在早期POAG患者的眼睛中，变异系数（CV）与上方RNFL厚度之间存在显著负相关（r = -0.5；P = 0.018），六边形细胞百分比（六边形度）与垂直杯盘比之间也存在显著负相关（r = -0.43；P = 0.035）。六边形度与上方以及下方RNFL厚度之间存在显著正相关（分别为r = +0.53；P = 0.008和r = +0.50；P = 0.015）。然而，在晚期青光眼患者的眼睛中，RNFL厚度与CEC参数之间未发现显著相关性。
与健康眼睛相比，早期或晚期POAG患者的眼睛中CEC参数未受影响，尽管RNFL和黄斑GCC明显变薄。在早期POAG患者的眼睛中，SD-OCT图像上CEC的形态特征（如CV和六边形度）与视神经乳头上方和下方的RNFL厚度之间存在显著相关性。需要进行更大样本量的未来纵向研究来验证我们的结果。
