Abstract
Purpose:
To evaluate the reduction in the metamorphopsia score (M-score) and the thickness of the retinal layers after vitrectomy for idiopathic epiretinal membrane (ERM), and to identify factors that predict the persistence of metamorphopsia.
Methods:
We reviewed the medical records of 27 eyes and 25 patients who had undergone vitrectomy for an idiopathic ERM. The changes in the visual acuity, M-score determined by M-CHARTS, and thickness of the inner nuclear layer (INL) and central foveal thickness (CFT) measured by spectral-domain optical coherence tomography (SD-OCT) were evaluated before and 6-months after the vitrectomy. The eyes were divided into 2 groups based on the presence or absence of metamorphopsia at 6-months after surgery. Group A had no or very reduced postoperative M-score (0 to 0.3; n=16) and Group B had persistent metamorphosia with M-scores >0.3 (n=11).
Results:
The M-score at 6-months after surgery was significantly correlated with the preoperative M-score (r = 0.57, P<0.01), visual acuity (r = 0.42, P<0.05), and INL thickness (r = 0.41, P<0.05). The preoperative M-score was significantly greater in Group B than in Group A (P<0.05), but the INL thickness was not significantly different in the two groups. The postoperative INL was significantly thicker in Group B than in Group A (P<0.05). The decrease in M-score was greater in Group A than in Group B (P<0.05), but the decrease in INL thickness was not significantly different.
Conclusions:
A persistence of metamorphopsia after surgery can be predicted by the preoperative M-score. The INL thickness was significantly decreased postoperatively in eyes with high preoperative M-scores (>0.3).