Occipital lobe tumors cause deficits in almost all cases, including visual field deficits, visual hallucinations occurring with or without seizures, and failure to recognize familiar faces (prosopagnosia). Visual hallucinations caused by occipital lobe lesions usually manifest as uniform flashes of lights of various shapes, as opposed to the typically formed images noted with temporal lobe lesions. Complete destruction of one occipital lobe causes contralateral homonymous hemianopia; bilateral lesions may cause Anton syndrome, in which the patient is cortically blind, but is not aware of his blindness. The patient denies his blindness and confabulates about his vision to others.
Visual hallucinations without seizures are strongly suggestive of occipital lesions. Although headache accompanies many brain tumors, few patients with headache have a brain tumor. Headache alone is the initial…
