Figure 2.

Iridal abnormalities and cataracts in the MCOA-phenotype. A) Iris stromal hypoplasia with miotic pupils with poor or no response to tropicamide was seen in all horses with the MCOA-phenotype. Cortical and nuclear cataractous changes in the lens contributed to the visual impairment. The horse in figure B) shows a regional abnormality of the pectinate ligament heralded by a widened, white perilimbal zone temporally (red arrows).