As with most conditions, prevention of a problem is better than treatment of a problem. The best time for keratoconus treatment is before astigmatism has become severe and vision has been lost. This does not mean that people with very poor vision from keratoconus cannot be helped by Corneal Cross-linking. However, the results of Corneal Cross-linking for patients with advanced keratoconus have not been as good as for patients with early disease.