What makes keratoconus difficult to treat?

Keratoconus. Because of the degree and extent of the "cone" and the irregular astigmatism it produces.
Keratoconus. Keratoconus now has a simple treatment to stop it from worsening called crosslinking. It is a safe one time treatment that makes the cornea stronger. However, it does not get patients out of contact lenses. It just prevents the condition from worsening, and in some cases, there is a nice improvement in vision after the procedure.