Efficacy of Pars Plana Vitrectomy with Internal Limiting Membrane Peeling for Treatment of Large Idiopathic Full-Thickness Macular Holes

Abstract
Purpose: To evaluate anatomical and visual outcomes of pars plana vitrectomy (PPV) with internal limiting membrane peeling (ILMP) in large idiopathic full-thickness macular holes (FTMH). Predictive factors also formed part of the study. Patients and Methods: A retrospective review of medical charts and optical coherence tomography images of patients with large idiopathic FTMH (≥ 400 μm) was conducted. Results: One hundred and fifty-eight eyes of 155 patients with a mean age of 62.94± 7.50 years were included in the study. Mean preoperative visual acuity (VA) was 1.26± 0.36 logMAR. Mean preoperative minimum linear diameter (MLD) and basal linear diameter (BLD) were 644.89± 136.85 μm and 1208.11± 307.14 μm, respectively. At 12 weeks postoperative follow-up, FTMH closure rate was 61.39% and mean postoperative BCVA was 0.92± 0.36 logMAR. Multivariate logistic regression analyses showed the anatomical outcome was significantly associated with BLD ≤ 1200 μm, preoperative vitreomacular interface (VMI) disorder and extended ILMP (a radius of 2 disc diameters), whereas only postoperative ellipsoid loss ≤ 500 μm was significantly associated with visual outcome. In subgroup analyses, the large FTMH group (400– 600 μm) had significantly better results in closure rate (70.97% vs 55.21%, P = 0.047) and visual results (P = 0.031) than the extra-large FTMH group (> 600 μm). Conclusion: PPV with conventional ILMP provided relatively low closure rate in large FTMH. Surgical success was significantly associated with BLD ≤ 1200 μm, no preoperative VMI abnormality, extended ILMP and postoperative ellipsoid defect ≤ 500 μm. Therefore, we suggest the extended ILMP if conventional ILMP technique is used. The large FTMH group had significantly better surgical outcomes than the extra-large group, so there is a need for reclassification of large FTMH.