Retinopathy following radiation therapy of paranasal sinus and nasopharyngeal carcinoma

Radiation retinopathy is a complication of the therapeutic irradiation of orbital and periorbital structures. The authors studied two groups of patients who had orbital (group 1) and periorbital (group 2) external irradiation. Radiation retinopathy occurred in 63.6% of patients in group 1 and 36.3% group 2. Retinal radiation damage showed a different clinical evoluation in the two groups, appearing earlier (mean, 11 versus 55 months) and with greater involvement of the peripheral retina in group 1 (with three cases of neovascular glaucoma). This study demonstrates that radiation retinopathy occurs in a significant number of cases when the eye is not totally involved in the irradiation field and shows at least two different clinical aspects in relation to the radiation treatment. It also suggests that portal design and choroidal circulation damage may represent important factors in the development of radiation retinopathy.