Care of systemic disease
Sickle cell disease is a systemic disease that affects several organs in the body. Management of the underlying disease can therefore prevent the development of retinopathy and slow its progression. Fetal haemoglobin transfusion - Fetal haemoglobin (HbF) is a form of haemoglobin that is found in children up to 6 months after birth. This type of haemoglobin is beneficial in sickle cell patients as it resists modification to the sickled shape. As a result, transfusion of HbF in younger populations can prevent and slow the progression of sickle cell retinopathy. Hydroxyurea administration - Hydroxyurea is a drug that can be used as an alternative method of increasing fetal haemoglobin levels in the blood of a patient with sickle cell disease. Hydroxyurea also provides the benefit of reducing inflammation. Haematopoetic stem cell transplantation - This process is more commonly known as a bone marrow transplant. It is useful in the management of sickle cell disease. However, access to this method is limited due to cost and the need for a donor that is biologically compatible with the person requiring the transplant. Anti-inflammatory and anti-adhesive drugs reduce the likelihood of occlusions in the small blood vessels of the retina therefore preventing the development of sickle cell retinopathy. There drugs include anti adhesive antibodies, anti-integrin antibodies, anti-Willebrand factor, sulfasalazine and statins. Gene therapy has also been proven beneficial in the prevention of sickle cell retinopathy. Treatment
Medical
Vascular endothelial growth factor (VEGF) is known to be associated with sea fan lesions which are types of neovascularization.
Bevacizumab is an anti-VEGF drug used in intravitreal injection that is known to cause reversal of sea fan lesions and reduce the duration of vitreous hemorrhage. Intravitreal injection of anti-VEGF drugs can also be used prior to surgery to aid separation of tissues involved in the sea fan lesion 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 neovascularizationThere 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.