I have one pupil dilating more than the other in dim light. What causes it?

Hi,

Welcome to icliniq.com.

I have gone through the attachment (attachment removed to protect patient identity). I have evaluated your eyes and pupils very patiently, and I agree with the findings of anisocoria. Now, there are many causes to have anisocoria such as some medications, nerve palsies, Horner's syndrome, and Addie's pupil.

To confirm the diagnosis or the exact cause of anisocoria, we need to check pupillary reflexes, near reflex, accommodation reflex, eye movements, corneal sensations, and visual acuity. You may also need to do MRI of a brain to rule out any intracranial mass or an aneurysm.

There is no single disease which explains all your symptoms of anisocoria, vertigo and heart disease like arrhythmia. I would recommend you to relax and get all the above mentioned clinical tests done such as pupillary reflexes (direct and consensual), near reflex, accommodation reflex, convergence reflex, eye movements, visual acuity, and corneal sensations.

These are the clinical tests done routinely by an ophthalmologist, and these tests will give us an idea about the cause of anisocoria. Once when the diagnosis is made, we can plan for the treatment. But there is no single disease which explains all these three symptoms.