Formation and evolution of idiopathic lamellar macular hole-a pilot study

BACKGROUND: The developmental pathways and subsequent evolutional processes of idiopathic lamellar macular hole (LMH) were studied with spectrum domain optical coherence tomography (SD-OCT). METHODS: Twenty-seven eyes of 26 patients of idiopathic LMH with pre-LMH SD-OCT available were retrospectively reviewed. Relevant OCT parameters and best-corrected visual acuity (BCVA) were collected and analyzed. RESULTS: Four types of developmental pathways of idiopathic LMH were noted. Type 1 (5 cases), involved disruption of a foveal cyst from vitreomacular traction. Type 2 (10 cases), demonstrated rupture of parafoveal cysts or schisis mainly from epiretinal membrane (ERM). In type 3 pathway (5 cases), a central intraretinal cyst formed under tight ERM with subsequent cyst roof dehiscence. Type 4 (7 cases), showed gradual loss of foveal tissue without cystic lesions from ERM traction. There was no statistically significant change in BCVA during LMH formations or subsequent evolutional processes in any types of the developmental pathways. Three cases developed epiretinal proliferation (EP) during evolution, which showed tendency of decrease in BCVA. Among the three cases, one later developed the degenerative configuration. CONCLUSIONS: In summary, four types of tractional developmental pathways of idiopathic LMH were identified. BCVA was relatively stable during LMH formation and follow-up. Deterioration of visual acuity were found in cases that developed EP during evolution. Transformation into degenerative configuration might be possible after LMH formation.