• Radiation retinopathy is a delayed onset, chronic, progressive, occlusive vasculopathy of the retinal circulation resulting from previous radiation treatment to the eye, orbit, head, or neck.
– It can be divided into nonproliferative and proliferative retinopathy.
• Varies by total radiation dose, mode of delivery (brachytherapy vs. external beam), fraction size, and isotope.
• Rare when dose is <40 Gy.
• Incidence peaks 2–3 years post radiation exposure.
Depends on the length of follow-up
• High dose per fraction
Loss of retinal capillary endothelial cells leading to vascular incompetence and eventually occlusion and nonperfusion.
Radiation induced free radical formation causing direct damage to endothelial cells. Radiation induced damage to cellular chromosomal DNA.
Previous radiation treatment to the eye, orbit, head, or neck.
• Capillary dilation
• Cotton wool spots
• Macular edema
• Intraretinal hemorrhages
• Lipid exudates
• Vascular sheathing
• Neovascularization of the retina, disc, or iris
• Vitreous hemorrhage
• Retinal detachment
DIAGNOSTIC TESTS & INTERPRETATION
• Careful slit lamp examination for anterior segment neovascularization
• Tonometry and gonioscopy to monitor neovascular glaucoma
• Diagnosis is usually made clinically.
• Fluorescein angiography may show microaneurysms, telangiectasias, capillary nonperfusion, neovascularization, and cystoid macular edema.
• Optical coherence tomography may demonstrate cystoid macular edema.
Diabetic retinopathy, hypertensive retinopathy, arteriole obstruction, venous occlusions, ocular ischemia syndrome
• Loss of visual function due to nonperfusion is irreversible and permanent.
• Focal or grid laser treatment may be beneficial for vision loss associated with macular edema. Panretinal photocoagulation is indicated for optic nerve, retinal, or anterior segment neovascularization.
Anti-VEGF (bevacizumab or ranibizumab) therapy for macular edema or neovascularization may provide short-term benefit.
COMPLEMENTARY & ALTERNATIVE THERAPIES
• Monocular precautions
• Polycarbonate lenses
Vitrectomy surgery for patients with vitreous hemorrhage or retinal detachment.
An ophthalmologist should be consulted every 3–6 months.
Monitor visual acuity, IOP, slit lamp exam, and dilated fundus exam for neovascular complications.
Radiation retinopathy is a slowly progressive condition that often leads to irreversible vision loss.
• Visual loss
• Neovascular glaucoma
• Archer DB, Amoaku WM, Gardiner TA. Radiation retinopathy – clinical, histopathological, ultrastructural and experimental correlations. Eye 1991;5:239–251.
• Gunduz K, Shields CL, Shields JA, et al. Radiation retinopathy following plaque radiotherapy for posterior uveal melanoma. Arch Ophthalmol 1999;117:609–614.
• Monroe AT, Bhandare N, Morris CG, et al. Preventing radiation retinopathy with hyperfractionation. Int J Radiat Oncol Biol Phys 2005;61:856–864.
• 362.10 Background retinopathy, unspecified
• 362.15 Retinal telangiectasia
• 362.29 Other nondiabetic proliferative retinopathy