Long-term Effect of Panretinal Photocoagulation Combined With Intravitreal Bevacizumab in High-risk Proliferative Diabetic Retinopathy

Abstract

Purpose: To evaluate long-term effects and usefulness of combined intravitreal injection of bevacizumab and panretinal photocoagulation (PRP) in patients with high-risk proliferative diabetic retinopathy. Methods: The authors retrospectively reviewed the records of 40 patients (40 eyes) with high-risk proliferative diabetic retinopathy who had been treated with PRP alone (laser treatment group, n=20) or intravitreal bevacizumab before PRP (combined treatment group, n=20). Changes in best corrected visual acuity (BCVA), central macular thickness (CMT) and the total area of leakage from active new vessels (NVs) were compared between the groups at one, three, and six months and at one year post-treatment. Results: In the combined treatment group, CMT decreased significantly at one month (p=0.021), and the areas of active NVs decreased significantly at one month (p=0.001) and three months (p=0.014) compared to those of the laser treatment group. However, there were no differences between the two groups after three months. In the combined treatment group, elevated intraocular pressures were found in three cases after one month, and there were vitreous hemorrhages in two cases after three months. Conclusions: The combined treatment showed significant early improvements in BCVA, CMT, and NVs regression for up to three months. However, long-term follow-up and additional treatment was necessary in the patients with persistent or recurred NVs and macular edema after three months.