Anisocoria is defined as inequality between pupil diameters
- unequal pupil size, which may represent a benign physiologic variant or a manifestation of disease. Pathologic anisocoria reflects an abnormality in the musculature of the iris or in the parasympathetic or sympathetic pathways that innervate the pupil.
- physiologic anisocoria refers to an asymmetry of pupil diameter, usually less than 2mm, that is not associated with disease
Differential Diagnosis:
General
- congenital
- tabes dorsalis
- trigeminal neuralgia
- carotid aneurysm
- aortic aneurysm
- unilateral intracranial mass
- glaucoma
- Adie's Pupils
Miosis (Pupil constriction) of one, but not the other
- iritis
- cervical sympathetic paralysis
- miotic drug (e.g. Pilocarpine)
Mydriasis (pupil dilatation) of one, but not the other
- mydriatic drug (e.g. Atropine)
- cranial Nerve III paralysis
- acute glaucoma