and to reduce intraoperative and postoperative hemorrhage. It is useful in combination with photocoagulation. Laser Indications for laser photocoagulation include Peripheral neovascularization of upwards of 60° circumference Sickle cell retinopathy affecting both eyes Large elevated sea fans Rapid progression of neovascularization There are two methods of photocoagulation mainly used; feeder vessel coagulation and scatter laser coagulation. The first method closes the vessels that supply the neovascularized areas using laser burns. Both the xenon arc and argon laser can be used however, the argon laser carries a reduced risk of complications. In comparison, scatter laser coagulation has an indirect effect. Ischemic retina produces vascular endothelial growth factor (VEGF) which promotes neovascularization. Scatter laser coagulation destroys this ischemic retina using laser burns thus preventing vitreous hemorrhage, retinal detachment and vision loss. Surgery Surgical intervention is indicated for severely advanced disease that poses a threat to visual acuity. Indications include longstanding vitreous haemorrhage, vitreous haemorrhage in both eyes, vitreous haemorrhage in patients with only one eye, epiretinal membranes, macular holes and the various forms of retinal detachment. Scleral buckle was a previously popular surgical intervention however, its complications include anterior segment ischemia as a result of vascular occlusion. The vascular occlusion can in turn lead to phthisis bulbi. Pars plans vitrectomy is useful for the management of vitreous haemorrhage. Its complications include cataracts, hyphema, glaucoma and unresolved vitreous haemorrhage. References Disorders of choroid and retina Sickle-cell disease Ophthalmology