Purpose: To present a case report with 'unclear' and sudden decrease of left eye visual acuity and bilateral visual fields defects. Conclusion: Optic disc drusen are often asymptomatic, frequently it is an accidental finding during the biomicroscopy of fundus due to ordinary eye examination.
Rarely, optic disc drusen can cause blood circulation failure on the optic disc with typical defects of the visual field. That's why we shouldn't forget the optic disc drusen in the differential diagnosis considerations.