September 2009

Don’t Assume Status Quo for Traumatic Aniridia

Presentation and History

A 79-year-old man who had recently moved to my area was seeking a replacement contact lens for his left eye. He had a history of traumatic aphakia and aniridia in his left eye. He had been wearing a soft toric lens with an opaque artificial iris print. His current contact lens (+14.50 –1.25 x 090) undercorrected his hyperopia and astigmatism, leaving him at 20/60 for distance.

Clinical Evaluation, Treatment and Outcome

A spherocylindrical over-refraction indicated a new prescription: +17.50 –3.25 x 115. Although the patient’s previous eye doctor had replaced this lens many times using the old parameters, my clinical data showed it was time to update the prescription.

I ordered a Kontour custom toric lens with an opaque print and a 3-mm pupil in the new prescription, which corrected the patient’s vision to 20/25. The patient commented that his vision was significantly better than it had ever been since the accident.

Discussion

When you inherit a complicated contact lens patient, it’s tempting to prescribe the same lens parameters as the patient had been wearing. It’s also tempting to not fully correct the entire cylinder you find during an examination. Yet, if you order a lens based on your clinical data, you often can improve your patient’s vision and quality of life.

The glare from aniridia can be debilitating, so you should use an opaque print on the lens with an artificial pupil in most cases. If the lens decenters slightly so that the pupil aperture does not align perfectly with the visual axis, simply order a larger pupil aperture.

Many patients with traumatic iritis are left with a corneal scar and resulting irregular astigmatism, which would make a printed GP a better choice for this type of presentation.

By Donald J. Siegel, OD
Sun City West, Ariz.

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