Comparison of Visual Outcomes between Panretinal Photocoagulation and Panretinal Photocoagulation Plus Intravitreal Bevacizumab in Proliferative Diabetic Retinopathy Patients Treated at Northen Zonal Hospital

Introduction: Diabetic retinopathy is one of the rigorous microvascular complications of diabetes mellitus is the significant cause of visual impairment and consequently blindness affecting about 36% of the diabetic population. Diabetic macular edema (DME) and proliferative diabetic retinopathy (PDR) are two prime manifestations of DR that are responsible for visual morbidity. The basis of the treatment in PDR is Laser photocoagulation as accomplished by Diabetic retinopathy treatment study (DRS) and early treatment diabetic retinopathy study (ETDRS) for the last two decades. The dawn of intravitreal anti-VEGF agents has revolutionized the management of diabetic eye disease for more than the last decade. The aim of the study is to compare the visual outcomes of diabetic retinopathy patients between pan-retinal photocoagulation and pan-retinal photocoagulation plus intravitreal Bevacizumab.

Methodology: A hospital-based cross-section study using medical record information for all DR patients treated by PRP and IVB at the KCMC eye. Data were analyzed using SPSS version 20.

Results: A number of 204 patients were included in the study. The mean age was 59.26 (SD=9.6) years; 75.4% were male. Most of the patients 71.1% are from Arusha and Kilimanjaro. Among all, 51% had PRP alone and the duration of Diabetes was 5-10 years in the majority. The mean VA for PRP alone was 0.89 (SD=0.89) before treatment while it was 1 (SD=0.99) in PRP plus Bevacizumab. At 3 months after treatment VA for PRP alone was 0.947 (SD=0.93) and 0.96 (SD=1.01) for PRP plus Bevacizumab. The mean difference was not statistically significant. VA improved by 49% and it deteriorated by 27.7%. The majority had early proliferated DR 49.7%, 42.8% high risk proliferated DR and advanced proliferated DR was 7.5%. The complications were found in 5.6% and they included: vitreous hemorrhage (4.6%) and retinal detachment (1%) in PRP plus Bevacizumab and none in PRP alone.

Conclusion: With respect to this study there is no significant difference in visual outcome for PRP alone and PRP plus injection Bevacizumab, though PRP plus Bevacizumab in treatment of DR had better visual outcome over PRP alone. PRP plus injection Bevacizumab is associated with a higher and early rate of regression of active NVs than PRP alone in patients with PDR. Further studies will be needed to determine whether IVB plus PRP is a satisfactory treatment for the prevention of vision-threatening complications such as vitreous hemorrhage and tractional retinal detachment.