Optic disc drusen and tumours of the chiasmal region.

Two patients with optic disc drusen and tumour of the chiasmal region are presented. The association of optic disc drusen and intracranial space-occupying lesion is probably a chance occurrence. In spite of the recognition of the optic disc drusen, certain findings indicate further examinations. Progressive loss of central visual acuity unexplained by retinal pathology is an indication for a neurological investigation. Bitemporal and homonymous hemianopic visual field defects as well as evidence of papilloedema warrant a neurological evaluation.