Pedicle Internal Limiting Membrane Flap Technique for Very Large Macular Holes: a Preliminary Report

Background: Conventional vitrectomy technique for macular hole surgery has a good outcome in small and medium macular holes, but for very large macular holes (minimum linear diameter higher than 700 μm) other techniques were developed aiming to achieve greater rates of closure and visual acuity gain. The purpose of this article is to report the anatomical and functional outcomes of four very large macular hole (MH) cases which have undergone vitrectomy with the pedicle internal limiting membrane (ILM) flap technique.

Methods: This is a retrospective series of four patients with large MH who were treated with vitrectomy and the pedicle ILM flap technique. Comprehensive ophthalmologic evaluation was performed before surgery and included ETDRS best-corrected visual acuity (BCVA) and spectral domain optical coherence tomography (SD-OCT) for MH measures: height, minimum linear diameter (MLD) and external base diameter. The particular detail of this technique is related to ILM flap creation. During the peeling, the ILM was not removed completely from the retina but was left attached to the edges of the macular hole and subsequently trimmed with the vitrectomy probe using the scissors mode.

Results: Four patients with very large MH underwent PPV and the pedicle ILM flap technique was used to pursue macular closure. Median preoperative BCVA was 20/400 (range: 20/320 to 20/400) and median postoperative BCVA was 20/200 (range: 20/320 to 20/200). Of the 4 cases reported, 3 obtained anatomical closure (75%), and also presented BCVA improvement after surgery, considering the last follow-up visit of each case. No additional procedures were performed in either case. One patient demonstrated no anatomic and functional improvement.

Conclusion: The present study describes the first Brazilian case series of very large MH treated by the inverted pedicle ILM flap technique. This technique was associated with anatomic and visual improvement in most cases, and represents an alternative therapeutic approach for large macular holes. Project registered in Plataforma Brasil with CAAE number 30163520.0.0000.5440 and approved in ethics committee   from  Ribeirão Preto Medical School Clinics Hospital, University of São Paulo-Ribeirão Preto, São Paulo, Brazil (appreciation number 3.948.426 gave the approval).