Internal limiting membrane removal in macular hole surgery for severely myopic eyes: a case-control study

Aims: To determine the surgical outcome of indocyanine green (ICG) assisted retinal internal limiting membrane (ILM) peeling in macular hole surgery for severely myopic eyes and compare the visual and anatomical outcomes with an emmetropic control group. Methods: 10 severely myopic eyes (-6.0 D or greater) of 10 patients with macular holes without retinal detachment were recruited prospectively. All eyes received ICG assisted ILM removal of 3-4 disc diameters around the macular holes. Cases were matched with a prospective control group of 10 emmetropic macular hole patients who underwent identical ICG assisted ILM peeling surgery in the same period. Results: The mean refractive error in the myopic and control group was -11.8 D and +0.3 D, respectively (two tailed t test, p < 0.001). The mean follow up duration for the myopic and control group was 12.1 and 13.3 months, respectively (two tailed t test, p = 0.63). The primary anatomical closure rate in both groups was 90% (Fisher's exact test, p = 1.0). For both the myopic and control groups, there were significant improvement in the mean log MAR visual acuity after the surgery with improvements from 0.86 to 0.57 for the myopic group (two tailed t test, p = 0.015) and 0.89 to 0.44 for the control group (two tailed t test, p = 0.002). The mean preoperative and postoperative visual acuity, rates of final visual acuity of 20/50 or better, and improvement of two or more lines were not statistically different between the two groups. Conclusion: ICG assisted ILM peeling in macular hole surgery for severely myopic eyes without retinal detachment gives promising anatomical and visual outcomes, which are comparable to that of non-severely myopic eyes.