Radiation Retinopathy

Radiation Retinopathy
SYMPTOMS Central vision loss and Peripheral vision loss
At 3 years post-radiation treatment, about 50% of patients saw 20/200 or worse with little to no chance of visual improvement even with treatment
SIGNS Signs typically develop 6 months to 3 years post-radiation treatment
Non-proliferative signs: Microaneurysms, Dot/blot hemorrhages, Flame hemorrhages, Cotton wool spots, Exudates, Cystoid macular edema, Optic nerve edema, Optic nerve pallor, Atrophy of the RPE
Proliferative signs: All of the signs seen with non-proliferative radiation retinopathy and NVD, NVE, Subhyaloid hemorrhages, Preretinal hemorrhages, Intravitreal hemorrhages
WORK-UP Pupils, EOMs, Full eye exam with dilated retinal exam, OCT analysis of the macula (signs of cystoid macular edema are best seen with an OCT), OCT analysis of the optic nerve, OCT-Angiography, Fluorescein Angiography, Indocyanine Green Angiography, Fundus Autofluorescence, Fundus photos, Infrared photos, B-scan ultrasound (if unable to view the retina), Watzke-Allen test, Macular photostress test, Amsler grid
TREATMENT Give take home Amsler grid in order to monitor for change
Patient needs to follow-up with their ocular oncologist
Patient needs to use caution with any strenuous exercise or activities in the presence of proliferative radiation retinopathy
Patient should sleep with their head elevated in presence of a preretinal, subhyaloid, and/or intravitreal hemorrhage
Consider discontinuing or lowering the dosage of any blood thinners in the presence of proliferative radiation retinopathy (needs to be discussed with PCP)
Non-proliferative radiation retinopathy: Needs to be monitored closely. There is no ocular treatment
Non-proliferative radiation retinopathy with cystoid macular edema: Refer to retinal specialist ASAP for treatment
Proliferative radiation retinopathy with or without cystoid macular edema: Refer to retinal specialist ASAP for treatment
FOLLOW-UP If there is no evidence of retinopathy, patient should be seen back in 3-6 months
If there is evidence of non-proliferative radiation retinopathy, patient should be seen back in 1-2 months
If macula is stable (in a patient with non-proliferative radiation retinopathy) following treatment by retinal specialist, patient should be seen back in 2-4 months
Once proliferative radiation retinopathy becomes involutional or quiescent and the retina and macula is stable following treatment by the retinal specialist, patient should be seen back every 3-4 months
ADDITIONAL LAB | TESTS The patient needs to follow-up with their PCP and ocular oncologist for additional testing if not already done which typically includes the following: CBC with differential, Liver enzyme panel, CT/Ultrasound of the abdomen, CT/Ultrasound of the liver, X-ray of the lungs, MRI/CT of the orbit
ETIOLOGY Radiation leads to an indirect creation of free radicals which causes retinal vascular endothelial cell damage, loss, and inflammation. This will cause damage to the retinal vasculature (especially capillaries) which will lead to leakage, hypoxia, and a decrease in perfusion
DIFFERENTIAL DX Diabetic retinopathy, Hypertensive retinopathy, Anemia retinopathy, Sickle cell retinopathy, Leukemia retinopathy
NOTES Radiation retinopathy typically occurs secondary to external beam radiation which is done for orbital tumors and plaque brachytherapy which is done for uveal tumors. Radiation retinopathy can also be related to radiation therapy to the head and neck.
Risk factors for the development of radiation retinopathy include the following: Radiation dose (higher total dose is linked with a higher risk of retinopathy), Level of dose fractionation, Size of tumor treated (a large tumor would involve a larger dose and a larger area of radiation), Other systemic diseases that can affect retina vasculature such as diabetes
Radiation Retinopathy: Fundus photo demonstrating proliferative radiation retinopathy https://imagebank.asrs.org/file/7341/choroidal-melanoma-with-radiation-retinopathy
Posted in Ocular Conditions, Retina-Vascular