Inverted internal limiting membrane-flap technique for large macular hole: a microperimetric study

BackgroundInverted Internal Limiting Membrane (ILM)-flap technique would seem to lead to higher closure rate and better visual acuity than traditional procedure with ILM peeling for the treatment of large macular hole (LMH). Visual acuity recovery does not reveal many other functional changes related to surgical approach. Our purpose was to evaluate macular function and morphology over a 1-year follow-up after inverted ILM-flap technique for LMH by using microperimetry in order to predict visual prognosis.MethodsThis study was a prospective unrandomized single-center study. 23 eyes of 22 patients with idiopathic LMH, with a minimum diameter ranging from 400 to 1000 mu m, were included. All patients underwent vitrectomy with inverted ILM-flap technique and gas tamponade. We analyzed macular hole closure rate and functional outcomes including best-corrected visual acuity (BCVA), macular sensitivity (MS) at central 12 degrees and central macular sensitivity (CMS) at central 4 degrees, and fixation behavior as bivariate contour ellipse area (BCEA, degrees(2)) at 68%, 95%, and 99% of fixation points measured by microperimeter, over a follow-up of 12 months.ResultsThe macular hole closure rate was 98%. The BCVA improved from 20/230 (Logmar, 1.060.34) to 20/59 (logMar, 0.47 +/- 0.45) at last follow-up (p<0.001). Retinal sensitivity and BCEA significantly improved (MS, p=0.001; CMS, p<0.0001; BCEA: 68%, p<0.01; 95%, p<0.01; 99%, p=0.001). Multiple stepwise regression analysis showed the final BCVA was significantly associated with macular hole size (beta =0.002, p=0.03), preoperative MS (beta=-0.06, p=0.001) and BCEA at 95% and 99% of fixation points (beta=-0.12, p=0.01; beta =0.06, p=0.01).ConclusionsInverted ILM-flap technique for LMH results in good morphologic and functional outcomes. Macular hole size and microperimetric parameters as preoperative MS and BCEA have a predictive role on post-surgical visual acuity.