Causes of Adie's Pupil and How It Is Treated

Adie’s pupil is a neurological disorder that affects how the pupil of the eye works. The function of the pupil is to control the amount of light entering the eye, and, with Adie's pupil, this doesn't narrow as it is supposed to. Because of this, a person may experience blurring and sensitivity to light.

Adie's pupil is diagnosed based on your symptoms and an eye exam. There is no cure for Adie's pupil, but symptoms can be managed with prescription eyeglasses and eyedrops.

This article describes the causes and symptoms of Adie's pupil, including how the condition is diagnosed and treated.

What Are the Symptoms of Adie's Pupils?

Adie's syndrome is the impairment of the normal constriction (narrowing) of the pupil when exposed to light. Rather than narrowing as it is supposed to, the pupil will remain open when lights are turned up.

The condition is often transient, meaning it may come and go on its own. But, in some people, Adie's pupil may be chronic (long-lasting) and even permanent.

With Adie's pupil, only one pupil is usually affected; it is rare for both eyes to be involved.

Symptoms of Adie's pupils include:

• Light sensitivity
• Blurred vision
• Trouble reading or focusing on things close to you
• Trouble performing fine motor skills, like threading a needle

People with Adie's pupil often have hyperhidrosis (excessive sweating) and a lack of a knee-jerk reflex, both of which are signs of neurological dysfunction. Occasionally, the colored part of the eye (called the iris) will become depigmented, losing most or all of its color.

Possible Complications

Though Adie’s pupil is not life-threatening, it can be debilitating. Adie's pupil can cause premature loss of near-focusing power similar to presbyopia. This can be especially difficult for younger people with otherwise excellent vision because one eye focuses just fine and the other doesn't.

Some people may also have difficulty with night vision or driving at night, limiting their ability to navigate stairs in a darkened theater or venture out after dark.

What Causes Adie's Pupil?

Adie's pupil is marked by damage to a group of nerves called the ciliary ganglion situated between the optic nerve and the lateral rectus muscle (the muscle that moves the eye laterally).

There are many potential causes for this, some of which include:

• Viral infections that sometimes target the optic nerve and surrounding tissues, such as shingles (herpes zoster), herpes simplex, mumps, or measles
• Bacterial infections that sometimes affect the optic nerve and surrounding tissues, like Lyme disease, cat-scratch fever, and syphilis
• Eye trauma, including nerve damage sustained following eye surgery

In a great many cases, Adie's pupil is idiopathic, meaning it has no known cause.

Adie's pupil generally occurs between the ages of 20 and 40. Females are affected more than males.

Diagnosis

Adie's pupil is largely self-evident given the lack of a pupillary response. Even so, the eye specialist (called an ophthalmologist) will want to identify the cause, if possible, and characterize the symptoms to deliver the appropriate treatment.

To start, the ophthalmologist will ask questions about your medical history (including any infections or injuries you recently had) and when you first realized your pupil sizes were different.

Next, the ophthalmologist will conduct a comprehensive eye exam, involving:

• Pupil response testing: A simple test to see how your pupil responds to bright and low light.
• Slit-lamp exam: This device magnifies and illuminates your pupils.
• Diagnostic eye drops: These cause pupils to dilate but may not work if you have Adie's pupil.

Can Adie's Pupil Be Cured?

There is no cure for Adie’s pupil, but there are ways to relieve symptoms of the disorder, including:

• Bifocal lenses or reading glasses to help with focusing issues
• Sunglasses to reduce light sensitivity
• Prescription eyedrops containing pilocarpine or brimonidine that reduce pupil size to aid with night driving and night vision

Prognosis

Because Adie's pupil is so poorly understood, the prognosis (expected outcome) can vary.

With that said, a good proportion of people will recover fully within a few months to two years. In some people, the affected pupil may become smaller over time and stay smaller than the normal pupil. In others still, the pupil response may never fully recover.

Summary

Adie's pupil is a neurological disorder in which the pupil of the eye doesn't narrow when exposed to light. This can cause blurring, light sensitivity, and an inability to focus on up-close objects. Typically, one eye is affected.

Adie's pupil can be diagnosed with a comprehensive eye exam. Treatment options include prescription eyeglasses, sunglasses to ease light sensitivity, and special eyedrops to reduce light sensitivity and improve night vision.