This is a disorder of the cornea and anterior chamber that is sometimes considered to be a form of anterior segment or mesenchymal dysgenesis. The primary feature is corneal clouding, most prominent peripherally and extending to the central cornea to a variable extent. Vascular arcades are usually present over the area of clouding and there is no clear limbal demarcation. Corneal fibers are often disorganized and larger than normal. The anterior chamber may appear shallow and the iris usually has a flat appearance, often with a posterior embryotoxon. Iris processes to the cornea and anterior synechiae are frequently present. Some degree of microcornea has also been noted in many cases. Rotary and horizontal nystagmus are uncommon. Sclerocornea may be a feature of cornea plana as well and the distinction between these disorders is unclear, especially in reported dominant pedigrees in which hyperopia is a feature.
Most cases are bilateral but there is often considerable asymmetry between the two eyes. Visual acuity is dependent on the extent of corneal opacification but may be normal. It is not a progressive disease.
