Asymmetric Choroidal Vascular Remodeling Following Temporal Inverted Internal Limiting Membrane Flap Surgery: A Retrospective Longitudinal Study

Abstract

Purpose To evaluate regional changes in choroidal thickness (CT) and choroidal vascularity index (CVI) in the nasal and temporal macula following temporal inverted internal limiting membrane (ILM) flap surgery for macular hole (MH).Methods In this retrospective longitudinal observational study, 29 eyes of 29 patients with idiopathic full-thickness MH undergoing temporal inverted ILM flap surgery were included, along with a control group of 29 age- and sex-matched healthy eyes. Spectral-domain optical coherence tomography with enhanced depth imaging (EDI-OCT) was performed preoperatively and at 2 weeks, 1, 3, 6, 9, and 12 months postoperatively. CT and CVI measurements were obtained at 1500 μm nasal and temporal to the foveal center. Nasal-temporal sectoral comparisons were performed using paired t-tests, and longitudinal changes were assessed using repeated-measures ANOVA with Bonferroni correction.Results Twelve patients (41.4%) were female, and the mean age was 68.5 years. The mean follow-up duration was 13.6 months. Postoperative changes were not uniform and were significantly more pronounced in the temporal macula, corresponding to the area of ILM manipulation. At the 2-week postoperative visit, total choroidal area, luminal area, CT, and CVI were significantly increased compared with baseline values in both nasal and temporal sectors (all p < .0001), with more pronounced changes in the temporal sector. When comparing sectoral differences relative to baseline, temporal CVI showed a significant reduction at 2 weeks and 1 month postoperatively (p = .001 and p = .035, respectively), indicating a transient regional vascular alteration.Conclusion Eyes with MH showed reduced CT and CVI preoperatively, followed by a significant postoperative increase after temporal inverted ILM flap surgery. These findings suggest that postoperative choroidal changes may not be uniformly distributed after temporal inverted ILM flap surgery. The more pronounced temporal changes in CVI may be related to surgical manipulation of the temporal ILM, although intrinsic nasal-temporal differences in choroidal structure may also contribute. These findings warrant further investigation in larger prospective studies.