Prediction of regression of retinal neovascularisation after panretinal photocoagulation for proliferative diabetic retinopathy

The purpose of this study was to evaluate the regression of neovascularization elsewhere (NVE) after panretinal photocoagulation (PRP) based on its location in relation to the internal limiting membrane (ILM). Participants in this retrospective case series were 47 patients with active NVE within the vascular arcade. All patients were treated with PRP and followed up for at least 12 months. The time to regression of NVE based on its location relative to the ILM on spectral domain-optical coherence tomography (SD-OCT) was analyzed. The proportion of eyes, showing regression of NVE at the end of follow-up period was 19/25 (76 %) in the "below ILM" group and 13/22 (59 %) in the "above ILM" group. The "below ILM" group was associated with a twofold enhanced regression of NVE in comparison to the "above ILM" group (HR = 2.13, p = 0.038). Regression of NVE is determined by its location relative to the ILM. Patients with "below ILM" NVE were found to show a twofold increased regression rate in comparison with the "above ILM" group, while the proportion of eyes showing regression of NVE at the end of the follow-up period was significantly greater in the "below ILM" than the "above ILM" group.