RETINOPATHY AFTER LOW-DOSE RETINAL IRRADIATION

A 28-year-old man, after subtotal resection of a Grade I-II frontal lo be astrocytoma, received 5600 cGy of radiotherapy in 200 cGy fractions to residual intracranial tumour. One year later he presented with sev ere bilateral retinopathy which, in appearance was consistent with ret inopathy from irradiation. Total irradiation received by the retina of each eye (<50 to 1500 cGy) was far less than the dose which commonly produces radiation retinopathy. Also, the pattern of retinopathy did n ot reflect the distribution of radiation received by the eye. Alternat ive causes for the retinopathy were sought but not found. Proliferativ e retinopathy occurred in each eye and one eye developed a dense vitre ous haemorrhage. Argon laser pan-retinal photocoagulation controlled t he neovascularisation in the other eye. This patient has developed sev ere retinal ischaemia after a low dose of retinal irradiation.