We retrospectively investigated the relationship between the appearance of IS/OS line on OCT images and visual acuity after resolution of DME by vitrectomy. Postoperative visual acuity of eyes with complete IS/OS after resolution of DME was significantly better than that without complete IS/OS, though macular edema was completely resolved in both groups.
Purpose: To evaluate the correlation between photoreceptor layer status following resolution of diabetic macular edema (DME) by pars plana vitrectomy (PPV) and final visual acuity (VA).
Methods: We retrospectively studied a series of 69 eyes from 58 patients with DME who were treated with PPV. Of the 69 eyes, 37 that were examined by optical coherence tomography (OCT) for at least 6 months and that showed a final macular thickness of less than 250 microm were included in this study. We assessed the integrity of the photoreceptor inner and outer segments (IS/OS) line in the fovea, using OCT in relation to their VA and other characteristics.
Results: There were no differences in initial VA or in foveal thickness between eyes with or without complete IS/OS at final observation. However, final VA without complete IS/OS was significantly poorer (P = 0.004). VA had improved by more than 2 lines in eight of ten eyes with complete IS/OS and in ten of 27 eyes without complete IS/OS; the groups differed significantly with regard to this percentage (P = 0.03).
Conclusions: The postoperative photoreceptor status of the fovea is closely related to the final VA after resolution of DME by PPV.