Ten-Year Follow-Up of Visual Outcomes After Vitrectomy for Clinically Non-Tractional Diabetic Macular Edema

This study evaluates the 10-year visual outcomes of vitrectomy for clinically non-tractional diabetic macular edema (DME). The medical records of 496 eyes of 332 consecutive patients who underwent vitrectomy for DME by one surgeon (NO) between August 1990 and June 2000 were retrospectively reviewed. A standard 20-gauge three-port pars plana vitrectomy was performed. The surgery consisted of phacovitrectomy for phakic eyes with the removal of the posterior hyaloid. The internal limiting membrane was peeled in 181 of the 496 eyes (36.5%). The eyes were divided into four groups based on the duration of the follow-up period (F): F<1 year (n=10), 1 year ≦F<5 years (n=128), 5 years ≦F<10 years (n=201), and 10 years ≦ F (n=157). The decimal visual acuities were converted to the logarithm of the minimum angle of resolution (logMAR) units and also to the corresponding Early Treatment Diabetic Retinopathy Study (ETDRS) letter scores. The main outcomes were the visual acuities. In addition, long-term visual outcomes after anti-vascular endothelial growth factor (anti-VEGF) treatments were investigated from previous reports. The postoperative follow-up period ranged from 4 to 280 months with a mean of 90.9 months. Three groups other than the F<1 year group had similar preoperative characteristics and visual outcomes. The mean letter score of the 10 years ≦F group was 51.9 before surgery, 61.7 at six months, 63.7 at 1 year, 63.4 at two years, 63.0 at three years, 62.6 at five years, and 60.0 at 10 years. The 10-year visual outcomes after vitrectomy for clinically non-tractional DME appeared to be good and stable. Further studies are expected to compare the long-term outcomes of vitrectomy and anti-VEGF treatments. Prospective blinded studies are needed to show efficacy.