This study will determine the efficacy of collagen cross linking for progressive keratoconus and ectasia after lasik. It will try and determine which is a more effective treatment: collagen cross linking alone or collagen cross linking combined with Intacs, a treatment which has already been proven to be effective in decreasing corneal curvature in patients with keratoconus.

In this study we will attempt to determine whether Collagen Cross Linking alone, one combined with insertion of INTACS is the most effective treatment for patients with progressive keratoconus in patients who have progressive disease.

These treatments have been widely used outside of the United States for the treatment of progressive keratoconus. Corneal Collagen Cross linking was recently approved in the United States for the treatment of progressive keratoconus. We will attempt to study 600 patients total. 300 patients will be assigned to cross linking only while another 300 will be assigned to cross linking and INTACS. Once adequate number of study subjects have been recruited data will be analyzed to determine which treatment is more effective. The following parameters from Topography, OCT and Tomography will be studied(these are Max K(pentacam) Kvalue(Tomey Topography)I-Svalue(Tomey Topography Astigmatism(Tomey Topography) and Min OCT(corneal pachymetry) any one of these metrics that achieve a value of 1 or more will be included in the analysis since the cornea is so irregular that values less than one could be artifact

Inclusion Criteria:

• progressive keratoconus or ectasia

Exclusion Criteria:

• cornea thinner than 400um
• K readings greater than 60D
• Central corneal scarring