Evaluation of Ganglion Cell-Inner Plexiform Layer Thickness after Vitreoretinal Surgery with Internal Limiting Membrane Peeling in Cases with Idiopathic Macular Hole

OBJECTIVES: To evaluate macular retinal ganglion cell-inner plexiform layer (GCIPL) thickness after vitrectomy with internal limiting membrane (ILM) peeling for idiopathic macular holes using spectral domain optical coherence tomography (SD-OCT). MATERIALS AND METHODS: Eighteen eyes of 18 patients with unilateral idiopathic macular hole who underwent vitrectomy with ILM peeling were retrospectively analyzed. Healthy fellow eyes of the patients and 18 eyes of 18 age-matched healthy individuals constituted the control group. The patients were evaluated at 1 day, 1 week, 1 month, and 3 months after surgery. The best corrected visual acuity (BCVA) measurements, biomicroscopic examination findings and SD-OCT measurements were recorded. Ganglion cell-inner plexiform layer thickness was evaluated with ganglion cell analysis software of Cirrus HD-OCT before surgery and at 1 month and 3 months after surgery and compared with control groups. Presence of dissociated optic nerve fiber layer (DONFL) was evaluated with C-scan mode. RESULTS: Of the 18 patients, 9 were male and 9 were female with a mean age of 65.6±5.6 (55-77) years. Preoperative BCVA was 0.75±0.19 logMAR, while it was 0.44±0.17 logMAR and 0.36±0.15 logMAR at postoperative 1 and 3 months, respectively (p<0.001). Postoperative mean GCIPL thickness was 66.33±17.28 µm. There was a correlation between mean GCIPL thickness and BCVA at postoperative 3 months (p<0.01). When compared with the control group, GCIPL thickness was significantly thinner in all quadrants of all patients at postoperative 3 months. Dissociated optic nerve fiber layer appearance was observed on C-scan in 13 of 18 eyes postoperatively. There was no correlation between the presence of DONFL and BCVA (p>0.05). CONCLUSION: Internal limiting membrane peeling during macular hole surgery may cause functional and/or structural changes that may be associated with visual acuity. Significant GCIPL thinning and DONLF appearance may occur postoperatively.