Abstract
Purpose:
Surgical treatment is recommended for idiopathic epiretinal membrane (ERM) with visual acuity of 20/40 or worse traditionally. Recent developments of surgical instruments and technique have been expanded indications for vitrectomy. The surgical outcomes for ERM with good visual acuity were investigated to evaluate rationale for early intervention for ERM.
Methods:
Twenty four eyes which had been diagnosed as idiopathic ERM with best corrected visual acuity (BCVA) better than 20/40 and were followed up for 12 months or more after vitrectomy and membrane removal, were investigated retrospectively. BCVA, metamorphosia, central foveal thickness, foveal shape, and status of photoreceptor inner/outer segment (IS/OS) junction were assessed based on the medical records and optical coherence tomography (OCT) images.
Results:
The mean follow-up period was 25.7 ± 13.3 months. The mean BCVA was not significantly changed from 0.26 ± 0.06 at baseline to 0.26 ± 0.22 at 6 months, and 0.27 ± 0.29 at 12 months after surgery. BCVA improved more than 2 lines in six eyes, and decreased more than 2 lines in 6 eyes. Four eyes had metamorphopsia, which persisted in all of them at 12 months. Central foveal thickness decreased significantly from 417 ± 86 μm at baseline to 335 ± 46 μm at 6 months (p<0.01), and 331 ± 42 μm at 1 year (p<0.01). Of 17 eyes without foveal depression at baseline, 11 eyes had foveal depression after 6.6 months in average. IS/OS signal was intact in 19 eyes, attenuated in three eyes, and disrupted in two eyes at baseline. It was recovered to be intact in 21 eyes, attenuated in two eyes, and disrupted in one eye at 12 months.
Conclusions:
Vitrectomy for ERM with good visual acuity resulted in anatomical improvement, but not functional improvement. Worsening of visual acuity was not rare, and would be related with surgical trauma. Decision for surgery in idiopathic epiretinal membrane with good visual acuity should be made cautiously, and the surgeon should attempt to minimize surgical trauma in the operation.
Keywords: 688 retina •
762 vitreoretinal surgery