Predictors for metamorphopsia in eyes undergoing macular hole surgery

Metamorphopsia is an important visual symptom of macular disease. We determined predictors for metamorphopsia investigating the relationships of macular hole (MH) diameter and retinal layer thicknesses with metamorphopsia after MH surgery. Forty-two eyes of 42 consecutive patients undergoing MH surgery were retrospectively studied. Metamorphopsia was measured with M-CHARTS. Inner nuclear layer (INL) and outer retinal layer (OR) thicknesses were measured 1000 μm away from central fovea at using Spectralis. Preoperative M-CHARTS scores correlated with MH diameters (P = 0.007-0.031) and changes of temporal OR thickness (P = 0.008-0.010). Postoperative M-CHARTS score at 3 months correlated with preoperative nasal and inferior OR thicknesses (P = 0.003 and 0.016) and with changes of superior INL at 3 and 6 months (P = 0.011 and 0.025), and score at 1 month with change of temporal OR at 6 months (P = 0.033). Postoperative improvement of M-CHARTS scores correlated with changes of temporal INL and superior OR (P = 0.026 and 0.002). Multiple regression analysis revealed that MH diameter was a significant predictor for metamorphopsia. Photoreceptor displacement and inner retinal change may generate metamorphopsia in MH undergoing surgery, however MH diameter is the most powerful predictor.