What is Anisocoria?

Anisocoria refers to a difference in the size of the pupils of the eyes. Normally, the pupils are equal in size, but in some cases, anisocoria can occur due to a variety of conditions.

Physiological Anisocoria: Some individuals may have a slight difference in pupil size that occurs naturally and does not indicate an underlying medical condition. This type of anisocoria is usually minimal and does not cause any symptoms or vision problems.

Pathological Anisocoria: Anisocoria can also be a sign of an underlying medical condition, particularly if it is sudden or accompanied by other symptoms. Possible causes may include:

1. Neurological Disorders: Damage to nerves that control the pupils, such as the oculomotor nerve or the sympathetic nerves, can lead to anisocoria. For example, in a condition called Horner's syndrome, the pupil on the affected side becomes smaller.

2. Brain Injuries: Head injuries or trauma to the brain can cause anisocoria as a result of damage to the neural pathways involved in pupil control.

3. Drugs and Medications: Certain drugs and medications, including some antidepressants, pain relievers, and eye drops, can cause anisocoria as a side effect.

4. Eye Conditions: Anisocoria can sometimes occur in certain eye conditions, such as iritis (inflammation of the iris) or uveitis (inflammation of the middle layer of the eye).

5. Structural Abnormalities: Rarely, anisocoria may be caused by a structural abnormality in one of the eyes, such as a congenital defect or a scar.

Importance of Evaluation: It's important to note that anisocoria can be a sign of a serious medical condition, especially if it is sudden or accompanied by other symptoms such as vision changes, headache, or weakness on one side of the face. If you notice any change in the size of your pupils or experience other concerning symptoms, it's crucial to see a healthcare professional for proper evaluation and diagnosis.