Damage to the Superior Retinae After 30 Gy Whole-Brain Radiation

Abstract Purpose The most common treatment protocol for whole-brain radiation therapy (WBRT) is 30 grays (Gy) in 10 fractions. This regimen entails a low risk of radiation retinopathy, with fewer than a dozen reported cases. Here we describe a case of radiation retinopathy that was confined to the superior retinae. These regions were the only portions of the eyes that were included in the treatment field. Methods Observational case report consisting of clinical examination, review of radiation treatment planning and implementation, computerized visual field testing, and fundus photography. Results A 36-year-old male with metastatic lung adenocarcinoma developed radiation retinopathy 16 months following WBRT to 30 Gy in 10 fractions. The retinopathy was largely confined to the superior halves of the retinae. There was corresponding geographic inferior visual field loss in both eyes. Review of the patient's treatment protocol revealed that the superior retinae received a substantial radiation dose, approaching 30 Gy, whereas the inferior retinae were essentially outside the treatment field. Conclusions In this patient the correlation between the treatment field and the resulting local development of radiation retinopathy demonstrated unequivocally that the relatively low dose used in routine WBRT (i.e., 30 Gy in 10 fractions) can induce radiation retinopathy.