A randomized clinical trial of scatter photocoagulation of proliferative sickle cell retinopathy. A randomized prospective clinical trial of argon laser scatter photocoagulation therapy for proliferative sickle cell retinopathy was performed on 116 patients (174 eyes) in Kingston, Jamaica. Ninety-nine eyes were treated with scatter photocoagulation and 75 eyes served as controls. The average length of follow-up was 42 months for the control eyes and 47 months for the treated eyes. Prolonged loss of visual acuity was statistically significantly reduced in the treated eyes. The incidence of vitreous hemorrhage was also significantly reduced in the treated eyes after controlling for the previously defined risk factors of vitreous hemorrhage and extent of proliferative sickle cell retinopathy at entry into the study. There were no complications associated with argon laser scatter photocoagulation. Scatter photocoagulation of proliferative sickle cell retinopathy is currently the most effective and safe way to treat patients with sea fan neovascularization. 