Purpose: To show the prognostic value of foveal microstructures using optical coherence tomography (OCT) for the restoration of inner segment/outer segment (IS/OS) junction layer following resolution of diabetic macular edema (DME).
Methods: Forty-one eyes of 39 patients with IS/OS damage at the time of DME that showed complete resolution of DME were included. Eyes were divided into 2 groups based on the IS/OS integrity at final visit, when edema was completely resolved: always damage group (damage at baseline and at final visit) and initial damage group (damage only at baseline). The OCT characteristics including the extent of the IS/OS damage, central subfield thickness (CST), maximum retinal thickness (MRT), presence or absence of subretinal fluid, duration of diabetic retinopathy, and duration of DME were studied. The integrity of IS/OS was evaluated at baseline and at last follow-up as percentage (0%-100%).
Results: Forty-four percent of eyes (18 eyes) achieved complete restoration of IS/OS after resolution of DME. There was no significant difference in CST or MRT during DME between the 2 groups. The always damage group had more IS/OS damage at baseline visit (23.6% ± 6.4% vs 10.7% ± 3.4%, p = 0.043) with a longer duration of DME (p = 0.025). Despite a borderline significance in visual acuity between the 2 groups at baseline (p = 0.05), the always damage group ended up with worse vision at last follow-up (p<0.001).
Conclusions: Patients with shorter duration of DME and less baseline IS/OS damage were more likely to have intact (restored) IS/OS after resolution of DME.