Transparency of the cornea is dependent on the uniform diameter and the regular spacing and arrangement of the collagen fibrils within the stroma.

Other treatments which may improve visual outcome includes optical iridectomy, phototherapeutic keratectomy and keratoprosthesises.

Depending on type and density of corneal opacity different types of keratoplasty may be used such as:[28] Optical iridectomy creates a clear entrance pupil, improving vision in patients with segmental corneal opacities.

An area of clear peripheral cornea can produce retinal images compatible with good visual acuity.

[30] Excimer laser phototherapeutic keratectomy (PTK) is useful in superficial (nebular) corneal opacities.

A study of live births in Spain reported that corneal opacities accounted for 3.11% of congenital eye malformations (Bermejo et al, 1998).

About 4% of keratoplasties done in the pediatric population in Denmark are due to congenital anomalies (Hovlykke et al, 2014).