Physiologic Anisocoria

Physiologic Anisocoria
SYMPTOMS Asymptomatic
SIGNS Anisocoria that is equal in light and dark (The anisocoria is usually 1mm or less), Normal light response, Normal near response
No other neurological signs
WORK-UP Pupils | EOMs | Full eye exam with dilation | Ptosis testing
TREATMENT No treatment needed
FOLLOW-UP Monitor in 1 year
ETIOLOGY Thought to be due to unbalanced supranuclear inhibition of the parasympathetic nuclei in the midbrain
DIFFERENTIAL DX Horner’s syndrome, Adie’s syndrome, Cranial nerve III palsy with pupil involvement
NOTES About 20% of the population has physiologic anisocoria
The amount of anisocoria may change throughout the day and may even show reversal