single session vs multiple-session panretinal photocoagulation for treatment of proliferative diabetic retinopathy

Conditions: Proliferative Diabetic Retinopathy; Diabetic Retinopathy; Diabetic Retinopathy Visually Threatening; Diabetic Macular Edema; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2

Summary: proliferative diabetic retinopathy (pdr) is the leading cause for blindness in working-age adults. the current gold standard treatment for pdr is panretinal photocoagulation (prp). in current clinical practice, both single-session and multiple-session prp approaches are widely accepted and utilized. the purpose of this study is to compare the safety and effectiveness of single-session and multiple-session prp.

proliferative diabetic retinopathy (pdr) is a well-known complication for both type 1 and type 2 diabetes mellitus (dm) and it is the leading cause for blindness in working-age adults. the current gold standard treatment for pdr, established more than four decades ago by the diabetic retinopathy study (drs), is panretinal photocoagulation (prp). the treatment goal is to halt the progression of pdr by destroying parts of the peripheral retina in a pattern fashion and hence preserving the visually important central macular region. the tissue destruction reduces the area of ischemia and reduces the production of vascular endothelial growth factor (vegf), which drives the formation of neovascular proliferations. in the management of pdr, panretinal photocoagulation (prp) stands as a cornerstone treatment. in current clinical practice, both single-session and multiple-session prp approaches are widely accepted and utilized. the choice between these approaches often depends on the practitioner's preference, patient characteristics, and specific clinical circumstances. although both single-session and multiple-session prp are employed in practice, there's an ongoing debate regarding their comparative safety and effectiveness. older studies suggest a heightened risk of diabetic macular edema (dme) with single-session prp, while newer research, particularly those involving milder laser techniques, indicates that the risk might be similar regardless of the number of sessions. this inconsistency in findings underscores the need for further research and the investigators aim to shed light over this with this prospective, controlled and randomized interventional study.

Eligibility criteria:
inclusion criteria: * age \> 18 years. * patients with type 1 or type 2 diabetes mellitus with newly diagnosed proliferative diabetic retinopathy, pdr. * visual acuity ≥ 0.1 snellen. * crt of less than 300 micrometer measured by oct without cysts in the neuroretina. * clear media and adequately dilated pupil for prp. exclusion criteria: * intraocular surgery within the last 4 months or planned within the next 3 months. * previous or current center-involved diabetic macular edema (ci-dme). * previous prp, intravitreal treatment (ivt), or macular laser treatment in study eye. * treatment with medications known to risk macular edema. * media opacity preventing adequate prp. * general medical condition making office laser treatment very difficult or impossible.

Keywords: panretinal photocoagulation (prp) single-session prp multiple-session prp navigated laser navilas central subfield retinal thickness (crt) macular volume optical coherence tomography (oct) swept-source optical coherence tomography (ss-oct) wide-field fundus imaging oct-angiography retinal oximetry electroretinogram (erg)