Inverted internal limiting membrane flap technique for large macular holes

Abstract

Purpose: Large macular holes usually have an increased risk of surgical failure. Up to 44% of large macular holes remain open after 1 surgery. Another 19% to 39% of macular holes are flat-open after surgery. Flat-open macular holes are associated with limited visual acuity. This article presents a modification of the standard macular hole surgery to improve functional and anatomic outcomes in patients with large macular holes.

Design: A prospective, randomized clinical trial.

Participants: Patients with macular holes larger than 400 μm were included. In group 1, 51 eyes of 40 patients underwent standard 3-port pars plana vitrectomy with air. In group 2, 50 eyes of 46 patients underwent a modification of the standard technique, called the inverted internal limiting membrane (ILM) flap technique.

Methods: In the inverted ILM flap technique, instead of completely removing the ILM after trypan blue staining, a remnant attached to the margins of the macular hole was left in place. This ILM remnant was then inverted upside-down to cover the macular hole. Fluid-air exchange was then performed. Spectral optical coherence tomography and clinical examination were performed before surgery and postoperatively at 1 week and 1, 3, 6, and 12 months.

Main outcome measures: Visual acuity and postoperative macular hole closure.

Results: Preoperative mean visual acuity was 0.12 in group 1 and 0.078 in group 2. Macular hole closure was observed in 88% of patients in group 1 and in 98% of patients in group 2. A flat-hole roof with bare retinal pigment epithelium (flat-open) was observed in 19% of patients in group 1 and 2% of patients in group 2. Mean (or median) postoperative visual acuity 12 months after surgery was 0.17 (range, 0.1-0.6) in group 1 and 0.28 (range, 0.02-0.8) in group 2 (P = 0.001).

Conclusions: The inverted ILM flap technique prevents the postoperative flat-open appearance of a macular hole and improves both the functional and anatomic outcomes of vitrectomy for macular holes with a diameter greater than 400 μm. Spectral optical coherence tomography after vitrectomy with the inverted ILM flap technique suggests improved foveal anatomy compared with the standard surgery.