Pupillary "dilatation lag" in Horner's syndrome

Abstract

1. Clinical examination will often fail to identify the presence of a unilateral Homer's syndrome. 2. Confirmation and localization of Homer's syndrome is of clinical prognostic value. 3. Cocaine testing provides confirmation of a Homer's syndrome, but it takes 45 min, is sometimes equivocal, and always delays the localizing hydroxyamphetamine test. 4. 'Dilatation lag' is a sensitive and physiological sign of Homer's syndrome, and can be demonstrated by simple Polaroid flash photographs.