The Pulfrich phenomenon in optic disc drusen

Optic disc drusen are hyaline bodies in the optic nerve head of unknown aetiology, 1 which are present in approximately 2% of the population. 2 Reduced visual acuity associated with optic disc drusen is rare, although visual field defects are common in cases of visible drusen. 3 4 Although the condition is frequently bilateral, asymmetry is usual. 5 We report a case of a patient with disabling visual symptoms associated with optic disc drusen. These were found to result from the Pulfrich phenomenon and were resolved by prescribing an appropriate ophthalmic tint.