Abstract
Abstract: :
Purpose: To determine the morphological and functional changes in the macula after pars plana vitrectomy for diabetic macular edema (DME). Methods: Pars plana vitrectomy was performed on 14 eyes of 13 patients with DME. A simple posterior vitreous detachment (PVD) was created in 10 eyes, and the internal limiting membrane (ILM) was peeled in 4 of these 10 eyes. In 4 eyes with a spontaneous PVD, the ILM was removed in 3 eyes and only the vitreous gel was removed in the other eye. The visual acuity (log MAR), multifocal electroretinograms (mfERGs), and optical coherence tomograpically (OCT)-determined foveal thickness were examined preoperatively and at 3 months postoperatively. Results: The preoperative visual acuity was 0.64±0.26 (mean±SD), and it improved significantly to 0.48±0.31 postoperatively (P=0.009). The foveal thickness was 454.6±184.1 µm preoperatively, and it was significantly reduced to 229.3±153.6 µm postoperatively (P<0.0001). The macular response density of the mfERGs was 7.04±3.29 nV/deg2 preoperatively, and 6.56±3.34 nV/deg2 postoperatively, a non-significant change (P=0.58). The peak latency of the macular mfERG was 31.6±5.1 msec preoperatively, and decreased significantly to 28.9±1.8 msec postoperatively (P=0.018). Conclusion: Vitrectomy for DME improved the visual acuity and foveal thickness significantly. In addition, a decrease of the peak latency of the macular mfERG indicated an improvement of the physiological function of the macula.
Keywords: diabetic retinopathy • electroretinography: clinical • vitreoretinal surgery