Comparison of intravitreal bevacizumab and panretinal photocoagulation for treatment of proliferative diabetic retinopathy without macular edema
Background: Proliferative diabetic retinopathy (PDR) is complication seen in patients with uncontrolled diabetes, resulting in visual loss in working-age individuals both in the developed and the developing nations. Left untreated it leads to blindness. Objective of this study was to compare short term efficacy of panretinal photocoagulation and intra-vitreal Bevacizumab in terms of visual acuity (better or worse) and neo-vascular regression in patients with proliferative diabetic retinopathy without macular edema.
Patients and methods: Prospective, randomized, interventional case series. Forty eyes of 20 PDR patients diagnosed clinically and further confirmed by fundus fluorescein angiography, unless contraindicated, and ocular coherence tomography for ruling out macula edema, were included in study. Patients were divided in 2 groups; Group A, panretinal photocoagulation (PRP) and Group B, intravitreal injection of anti-vascular endothelial growth factor (antiVEGF) Bevacizumab 1.25mg/0.05ml. PRP session (two weeks apart) for group A and injection Bevacizumab, monthly for three months for group B were planned. Baseline best-corrected visual acuity (BCVA), anterior segment and fundus examination and intraocular pressure (IOP) were recorded. Patients were examined one and six months from baseline. Main outcomes were BCVA, regression/ progression of neovascularization and vitreous hemorrhage at end of 6 months.
Results: Retinal neo-vascular regression observed after first follow-up with 70% clinical regression in Group A (PRP) and 15% in Group B (Bevacizumab). BCVA at baseline was similar in both groups 0.80±0.24 and 0.88±0.24 respectively. At 6 months, BCVA improved more in group A 0.60±0.20 than group B 0.92±0.13. Visual reduction was noted in group B due to progression of PDR with vitreous hemorrhage (VH) in 15% of group A and 30% of group B. Pars plana vitrectomy for persistent VH planned in 5% of Group A and 15% of group B eyes.
Conclusion: Short term follow up reveal anatomical and functional improvement in both groups with more so in PRP than Bevacizumab group in terms of BCVA, neo-vascular regression and VH. Further studies are required to assess the long term efficacy, compliance and safety of both treatment regimens