Quantitative Analyses of Retinal Traction Force and Metamorphopsia in Lamellar Macular Hole and Related Diseases

PURPOSE: To investigate the involvement of retinal traction in the pathogenesis of lamellar macular hole (LMH) and related diseases based on OCT–based consensus definition. DESIGN: Retrospective, observational study. PARTICIPANTS: Seventy-two eyes with LMH, epiretinal membrane foveoschisis (ERM-FS), or macular pseudohole (MPH). METHODS: To quantitatively evaluate the involvement and strength of retinal traction in their pathogenesis, retinal folds were visualized with en face OCT imaging, and the maximum depth of the parafoveal retinal folds (MDRF) was measured. Metamorphopsia was quantified by measuring the minimum visual angle of dotted lines needed to cause it to disappear using M-CHARTS (Inami). MAIN OUTCOME MEASURES: Maximum depth of retinal folds and M-CHARTS scores. RESULTS: Of the 72 eyes, 26 were classified as having LMH, 25 as having ERM-FS, and 21 as having MPH. Parafoveal retinal folds were observed in 7 (26.9%) eyes with LMH, 25 (100%) with ERM-FS, and 21 (100%) with MPH. The MDRF (7.5 ± 17.6 μm) was significantly smaller in LMH than in ERM-FS (86.3 ± 31.4 μm) and MPH (74.5 ± 24.6 μm) (both P < 0.001), whereas no significant difference in MDRF between MPH and ERM-FS was observed (P = 0.43). A significant positive correlation between MDRF and M-CHARTS scores was observed in ERM-FS and MPH (P = 0.008 and 0.040, respectively) but not in LMH (P = 0.073). CONCLUSIONS: Retinal traction was significantly weaker in the LMH group than in the ERM-FS and MPH groups. The MDRF was significantly associated with the degree of metamorphopsia in the ERM-FS and MPH groups. These results provide insights into the diseases’ pathophysiology and treatment strategy.