Comparison of Techniques: Inverted Flap and Conventional Internal Limiting Membrane Removal in Idiopathic Macular Hole Surgery

Overview

Aim: To compare functional and anatomical outcomes between the inverted flap technique and conventional removal of the internal limiting membrane (ILM) in the surgical management of idiopathic macular hole (IMH).

Material and methods: We retrospectively evaluated the anatomical and functional results in 67 eyes of 65 patients operated on for IMH. The patients were operated on either using the conventional ILM peeling technique (first group) or with the inverted ILM flap technique (second group). 43 eyes of 41 patients were included in the first group, 24 eyes of 24 patients in the second group. We indicated for surgery only patients with IMH stage 2–4 according to the Gasse classification. Best corrected visual acuity (VA) was always determined before and two months after surgery. Furthermore, a comparison of both techniques was made according to the average letter gain after surgery, and the effect of surgery was evaluated using OCT with regard to whether IMH closure succeeded. For both techniques, 25G PPV with SF6 tamponade was performed.

Results: Hole closure took place in 41 eyes with conventional ILM removal. In one eye, the hole did not close even after reoperation with the same technique. Median ETDRS letter gain was 7.0. VA remained the same in 2 eyes (4.7%), worsened in 7 cases (16.2%), and improved in all other cases (79.0%). In 16 eyes (37.2%), VA improved by 2 or more lines of ETDRS charts. Using the inverted flap technique, the hole was closed in all 24 monitored eyes. Median ETDRS letter gain was 9.5. VA remained the same in 2 eyes (8.3%), worsened in 2 cases (8.3%), and improved in all other cases (83.3%). In 12 eyes (50.0%), VA improved by 2 or more lines of ETDRS charts. There were no serious complications intraoperatively or postoperatively.

Conclusion: Our study demonstrated the safety and efficacy of both methods. Although the results were not statistically significant, the inverted flap technique recorded a greater ETDRS letter gain (9.5 vs. 7.0) and proportion of closed holes (100% vs. 95.3%) compared to the conventional ILM peeling technique in our set of eyes.

Keywords:

macular hole – 25-Gauge vitrectomy – MLI peeling – inverted flap technique – trypan blue – gas tamponade