Cerebral metastasis presenting with altitudinal field defect

A 75-year-old man presented with a unilateral inferior altitudinal visual field defect and a history of weight loss and night sweats. The acuity in the affected eye was 20/200, otherwise his ocular examination was normal. Neuroimaging demonstrated a post-fixed chiasm, with a frontal metastasis compressing the intracerebral portion of the optic nerve. A chest x-ray showed classical cannon ball lesions, secondary to malignant melanoma. This is the first case report of an intracerebral tumor producing an inferior altitudinal field defect.