anisocoria

Last reviewed 01/2018

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