Internal Limiting Membrane Flap Enhances Macular Hole Closure Rates in Highly Myopic Eyes: A Case-Control Study.

Purpose: To compare the anatomical and functional outcomes of macular hole (MH) surgery in high myopia (HM) versus non-HM eyes.

Patient and methods: This is a retrospective case-control study of patients who underwent MH repair between 2018 and 2022. HM was defined by axial length (AL) ≥26 mm. MH size, macular curvature and foveoschisis were graded. Surgical technique was divided into internal limiting membrane (ILM) peel or flap. Post-operative best corrected visual acuity (BCVA) and anatomical outcomes including hole closure, restoration of outer retinal layers, presence of foveal gliosis or foveal detachment were assessed at post-operative one, three, six and twelve months.

Results: Thirty-four HM eyes were matched 1:1 to 34 out of 201 non-HM eyes with using gender, age, MH size and concurrent phacoemulsification as covariates. Mean AL in the HM group was 28.46 ± 2.01 mm, ranging from 26.03 to 32.83 mm. MH size was 366±183 µm and 386±199 µm in HM and non-HM groups (p=0.667). BCVA and restoration of outer retinal layers were comparable between groups at all time points. Initial hole closure rate was comparable, with 29 (85.3%) in HM group vs 30 (88.2%) in non-HM eyes, p=0.720. One eye in the HM group re-opened 10 months post-operatively. Proportion of eyes with non-closure was higher in those who underwent ILM peel vs flap [7/34 (20.5%) vs 0/34 (0%), p=0.022]. Smaller MH was associated with better closure rate (OR 0.99, 95% CI 0.99-1.00). AL and macular curvature were not associated with hole closure (OR 0.91, 95% CI 0.72-1.15; OR 1.01, 95% CI 0.99-1.02 respectively). Larger MH was associated with poorer final BCVA (β=0.010, 95% CI 0.007-0.014).

Conclusion: Anatomical success was comparable between HM and non-HM eyes. Higher surgical success was associated with smaller MH size and ILM flap, but not influenced by AL, macular curvature or foveoschisis.