Minimum Rim Width and Lamina Cribrosa Depth in Non-Glaucomatous and Glaucomatous U.S. Veterans

Abstract

Purpose: Assess the utility of the MRW and lamina cribrosa depth measurements for detecting differences between non-glaucomatous and glaucomatous U.S. Veterans. Compare inter-eye differences of individuals with glaucoma. Method: 38 subjects were recruited per group: Group 1 included one eye of non-glaucomatous participants, and Group 2 included each qualifying eye of participants with glaucoma. Analysis compared Group 1 with the more affected eye only of Group 2 participants, and separately between the more and less affected eyes of group 2 participants. MRW measurements were obtained with Heidelberg Eye Explorer© (HEYEX). Average lamina cribrosa depths were measured manually utilizing HEYEX. Results: 26 subjects from Group 1 and 33 subjects from Group 2 were included. A significantly thinner MRW was found in glaucomatous eyes vs. non-glaucomatous eyes (210 µm vs. 309 µm; P < .001). The normative database in HEYEX had an 85% sensitivity and 92% specificity to detect glaucomatous nerves. Among the 27 participants in Group 2 who had both eyes tested, eyes with more advanced visual field loss showed significantly thinner global MRW compared to fellow eyes (203 µm vs. 224 µm P = .03). Lamina cribrosa depths were non-significantly deeper in glaucomatous vs. non-glaucomatous eyes (476 µm vs. 429 µm P = .17). Conclusions: The MRW parameter differentiates between glaucomatous and non-glaucomatous optic nerves. Lamina cribrosa depths were non-significantly deeper in glaucomatous vs. non-glaucomatous participants. Post-hoc inter-eye data analysis suggested that inter-eye differences in gMRW values of glaucomatous eyes reflect asymmetric damage as correlated with the visual field