Topical apraclonidine to diagnose Bernard-Horner syndrome

This study aimed at developing through three clinical cases, the usefulness of topical apraclonidine 0.5% to confirm a diagnosis of Bernard-Horner syndrome. Pupil diameter measurements were performed in indoor, bright and dim light successively. Apraclonidine 0.5% was then applied topically to both eyes, and pupils were observed at 30 and 60 minutes. Apraclonidine demonstrated denervation hypersensitivity in all three cases. Anisocoria was reversed in two cases and corrected in the third case. Although the cocaine test should still be considered as the gold standard for BHS diagnosis, apraclonidine seems to be a useful drug to confirm clinically diagnosed Bernard-Horner syndrome