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Anisocoria

Definition:

Anisocoria is unequal pupil size. The pupil is the black part in the center of the eye through which light passes.

Alternative Names:

Enlargement of one pupil; Pupils of different size; Eyes/pupils different size

Considerations:

Occasionally, a baby is born with different sized pupils and there is no underlying disorder. If other family members also have this condition, then pupil size is possibly genetic and is nothing to worry about.

At times, for unknown reasons, pupils may differ in size. If there are no other symptoms and if the pupils return to normal, then the temporary condition is nothing to worry about.

Unequal pupil sizes that develop later in life and persist are often a sign of a brain, blood vessel, or nerve disease.

Common Causes:

The use of eyedrops are a common cause of a harmless change in pupil size. Other medicines that get in the eyes, including medicine from asthma inhalers, can change pupil size.

Other causes of unequal pupil sizes may include:

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