Purpose: To report the efficacy and safety profile of subthreshold pan-retinal photocoagulation (PRP) using endpoint management (EPM) algorithm compared with conventional threshold PASCAL PRP for the treatment of severe non-proliferative diabetic retinopathy (NPDR).
Methods: This was a prospective, single center, paired randomized controlled trial of fifty-six eyes of twenty-eight participants with bilateral symmetric severe NPDR. One eye of the participant was randomly assigned to receive the subthreshold EPM PRP, while the other eye of the same participant received the threshold PASCAL PRP. The primary outcome measures included the difference in the one-year risk of progression to PDR between two groups, and mean changes of the logarithm of the minimal angle of resolution (logMAR) visual acuity (VA). The second outcome measures included central foveal thickness (CFT), one-year risk of progression to PDR, and visual field (VF) parameters.
Results: The subthreshold EPM PRP group and the threshold PASCAL PRP group had similar one-year risk of progression to PDR during the 12-month follow-up visits (17.86% vs 14.29%, P>0.05). Slightly decreased VA was found in both groups (0.08 vs 0.09 logMAR VA), however, no statistical difference was found for neither group (P>0.05). Similar results were found for thickened CFT for both groups (23.59μm vs 28.34μm, P>0.05). Specifically, although substantial loss of VF was found in the threshold PASCAL PRP group (P<0.05), no obvious damage to VF was seen in the subthreshold EPM PRP group (P>0.05).
Conclusion: The subthreshold EPM PRP is non-inferior to the conventional threshold PASCAL PRP in the treatment of severe NPDR during 12-month follow-up and could be an alternative treatment option for patients with severe NPDR.
Subthreshold Pan-retinal Photocoagulation Using Endpoint Management Algorithm for Severe Non-proliferative Diabetic Retinopathy: A Paired Controlled Pilot Prospective Study
