Long-term visual acuity results of treated and untreated radiation retinopathy (an AOS thesis)

Abstract

Purpose: To report ocular findings in eyes with radiation retinopathy and visual acuity (VA) results of photocoagulation for macular edema and proliferative retinopathy.

Methods: This retrospective case series compared VA after photocoagulation treatment and nontreatment of radiation macular edema. Visual outcomes were assessed with regression analyses.

Results: Eighty-seven eyes (78 [89.7%] treated with external beam irradiation and 9 treated with local plaques) were studied. Fifty-nine (67.8%) and 28 (32.2%) eyes had nonproliferative and proliferative retinopathy, respectively; macular edema developed in 42 nonproliferative eyes (71.2%) and 24 proliferative eyes (85.7%). Initial VAs (median) were 20/40 and 20/65 for nonproliferative and proliferative eyes, respectively, and final VA was 20/80 and 20/400. Initial VA (median) in eyes with macular edema was 20/50 compared to 20/25 in eyes without edema; final VAs were 20/200 and 20/30. Comparing treated (19 [45.2%]) and untreated (23[54.8%]) macular edema in 42 eyes with nonproliferative retinopathy, initial median VA (20/40 and 20/50) and final VA (20/100 and 20/200) were better in treated eyes. Regression analysis showed significant treatment effect (P = .003) when initial VA (logMAR) and months of follow-up were kept constant; treated eyes had mean final VA (logMAR) 0.36 (95% CI, 0.12-0.60) better than untreated eyes.

Conclusions: The presence of macular edema and proliferation indicates more severe retinopathy and worse visual prognosis than for eyes without macular edema and proliferation. Although these VA results suggest macular photocoagulation is beneficial, eyes with macular edema continue to lose vision despite treatment. Better prevention and treatment methods are needed for radiation retinopathy.

Figures

FIGURE 1

Left, Untreated clinically significant radiation macular edema. Fundus photograph of the right eye of a 42-year-old man 3 years following 7000 cGy of radiation for treatment of ethmoid sinus carcinoma. Visual acuity is 20/400. Exudates and retinal thickening are present in the center of the macula, and the optic disc is pale. Middle, Early venous phase of fluorescein angiography. Right eye angiogram shows capillary nonperfusion and irregular as well as enlarged capillary free zone. Right, Late-phase fluorescein angiography. Right eye angiogram shows leakage of fluorescein dye from the abnormal perifoveal capillaries and microaneurysms.

FIGURE 2

Left, Clinically significant radiation macular edema. Fundus photograph of the left eye of a 16-year-old boy 6 years following 5400 cGy of radiation for treatment of a medulloblastoma. Vision is 20/100. The center and temporal macula are edematous with exudates along the temporal rim of the edema. Middle, Late-phase fluorescein angiography. There is leakage of fluorescein dye in the inferotemporal macula. Right, Resolved clinically significant radiation macular edema. Fundus photograph shows macular photocoagulation scars at the site of prior leakage, and the macula is not edematous 3 years following treatment. Vision is 20/70. A small clump of exudates remains in the inferotemporal macula.

FIGURE 3

Left, Unresolved clinically significant radiation macular edema. Fundus photograph of the left eye of 25-year-old woman 7 years following 5040 cGy of radiation for treatment of nasopharyngeal rhabdomyosarcoma. Vision is 20/200. Exudates and photocoagulation scars surround the center of the macula, which is edematous. The macular edema was retreated with limited scatter burns through areas of capillary nonperfusion but not closer than 500 μm from the center of the macula. Middle, Early venous phase fluorescein angiography. The left eye angiogram shows capillary nonperfusion in the papillomacular bundle and hyperfluorescence of microaneurysms and telangiectatic vessels. Prior photocoagulation burns are round and hypofluorescent. Right, Late-phase fluorescein angiography. Fluorescein dye has leaked into the superotemporal macula.