Figure 1. Right (top) and left eyes, demonstrating near total absence of iris tissue.Figure 2. Iris processes spanning a dysgenic
trabecular meshwork.
Presentation

A 7-month-old boy was referred for nystagmus of both eyes. His parents reported the nystagmus started at 1 month of age. On initial evaluation he was found to have bilateral aniridia.

Medical History

The patient was the product of a normal pregnancy and uncomplicated repeat cesarean section. Birth weight was 5 pounds. Family history was unremarkable—there were no other family members with aniridia. He had one sibling, a healthy 2-year-old brother.

Examination

His extraocular motility was full without strabismus, and he was able to fix and follow with no preference for fixation with either eye. He demonstrated horizontal moderate frequency and moderate amplitude symmetric bilateral nystagmus with a null point in primary position. There was no anomalous head positioning.

 
Figure 3. Foveal hypoplasia with anomalous vessels present in the right (top) and left eyes.
Examination under anesthesia disclosed that he had deep and quiet anterior chambers and clear corneas without pannus or Haab striae. Corneal diameters were 10.75 mm OD and 10.5 mm OS. Corneal thickness was 650 µm and 641 µm respectively. Tonopen pressure was 13 mmHg OD and 12 mmHg OS. There was bilateral, almost complete aniridia with rudimentary iris stumps inferiorly, temporally and nasally (See Figure 1). Gonioscopy revealed a somewhat dysgenic trabecular meshwork that had multiple iris processes extending over the angle (See Figure 2).

Each eye was found to have a 1.5-mm anterior subcapsular cataract. Retinoscopy revealed a cycloplegic refraction of +3.50 +0.75 x 090 OD and +3.50 + 0.50 x 090 OS. A-scan ultrasound by immersion disclosed appropriate-sized globes for age with axial length of 19.77 mm OD and 19.81 mm OS.

Funduscopic evaluation disclosed normal optic nerves with moderate macular hypoplasia in each eye with anomalous vessels in the maculas (See Figure 3).

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