What are isocoric pupils?

Isocoric pupils are pupils that are equal in size. This is the normal state for pupils, and it is maintained by the balance between the sympathetic and parasympathetic nervous systems. When the sympathetic system is activated, the pupils dilate, and when the parasympathetic system is activated, they constrict.

Causes of isocoric pupils:

- Normal anatomy and physiology

- Pharmacological agents

- Medical conditions

* Opiate overdose/toxicity

* Increased intracranial pressure

* Brainstem lesions affecting the midbrain or pons

* Horner syndrome (paralysis of the sympathetic innervation to the eye)

* Adie's tonic pupil (a rare condition that affects the parasympathetic innervation to the eye)

Treatment of isocoric pupils

In most cases, isocoric pupils do not require treatment. However, if they are caused by an underlying medical condition, treating that condition may improve the pupil size.