Corneal ectasia is characterized by irregularity and thinning of the cornea, causing the cornea to bulge forward and cause distorted vision and impaired visual acuity. Corneal ectasia is a complication after refractive (LASIK) surgery. It is also the primary problem in keratoconus, a gradually progressive inherited condition that typically is manifested in young adulthood, more commonly in women. Treatment approaches to stabilize the cornea's shape include rigid contact lenses, surgical implantation of stiff plastic intrastromal corneal ring segments, a collagen cross-linking procedure and, in severe cases, cornea transplantation. The collagen cross-linking procedure involves topical application of a concentrated riboflavin (vitamin B2) solution after the corneal epithelium is scraped, followed by ultraviolet (UV) light exposure. UV light stimulates riboflavin to form new bonds (cross links) between the cornea's connective tissue, giving the cornea additional strength to maintain its shape and prevent the need for transplantation. The cost of one treatment using this system is $2,500 to $3,500. A small prospective study including 7 patients with keratoconus was started on a trial of oral riboflavin and 15 minutes of natural sunlight exposure daily. These patients reported no adverse effects and preliminary results showed corneal stabilization and/or corneal flattening in all 7 patients It is hypothesized that dietary riboflavin and natural sunlight is as effective in corneal crosslinking as the currently FDA approved Avedro therapy. If the clinical study confirms the investigators' early observations of the benefits of this approach, coupled with animal studies that document corneal cross-linking, the investigators will have data to pursue funding for larger clinical and animal studies. This has the potential to save millions of dollars in health care costs and ease the burden of treatment in patients who require therapy to induce corneal cross-linking to stabilize the cornea's shape.