Dr Ben Wild
Overview |
The iris, the colored part of our eyes, contains 2 muscles. One, the sphincter, is controlled by the parasympathetic nervous system and the other, the dilator, is controlled by the sympathetic nervous system. The interplay between these muscles controls the size of the opening in the middle of the iris known as the pupil. Pupil size is therefore controlled by the sympathetic and parasympathetic nervous systems and any defects along any of those nerve pathways can cause abnormal pupils.
Frontal view of an eye with a healthy pupil.
Adie's pupil, or syndrome, refers to a condition where the pathways of the parasympathetic nervous system get disrupted. This results in an enlarged pupil that is unreactive to light and possibly the loss of near vision. This can occur in one or both eyes and is occasionally inherited. In most cases it affects one eye and often occurs after a viral illness. If it occurs in both eyes, it may be due to auto-immune inflammation or infection from syphilis. As time passes, the enlarged pupil shrinks but remains non-reactive to light.
An enlarged irregularly shaped pupil even in bright light.
Signs and Symptoms |
Signs
Large irregularly shaped pupil (may be both pupils), missing or very slow reaction to light, pupil still shrinks when crossing eyes, pupils become small with age.
Symptoms
Light sensitivity and blur at near.
Causes and Risk Factors |
Causes
Loss of parasympathetic nerve supply to the affect eye.
Risk Factors
Viral infection (still unknown which viruses can cause this), syphilis infection.
Prevention and Treatment |
Prevention
There are no known preventative measures.
Treatments revolve around eliminating the symptoms because there is no known cure for the condition itself.
· 0.1% pilocarpine drops to shrink the pupil to reduce light sensitivity.
· Colored contact lenses to “shrink” the pupil to reduce light sensitivity.
· Reading glasses to help with near vision.
Prognosis |
An Adie pupil is not an indication of poor health and is not a cause for overall concern. It is, however, a condition without a known cure. Patients will deal with the light sensitivity and loss of near vision until the pupil naturally shrinks with age.
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