Corneal Collagen Crosslinking In Keratoconus And Other Eye Disease

Keratoconus is a condition characterized by biomechanical instability of the cornea, presenting in a progressive, asymmetric and bilateral way. Corneal collagen crosslinking with riboflavin and UVA (CXL) is a new technique of corneal tissue strengthening that combines the use of riboflavin as a photo sensitizer and UVA irradiation. Studies showed that CXL was effective in halting the progression of keratoconus over a period of up to four years. The published studies also revealed a reduction of max K readings by more than2D, while the postoperative SEQ was reduced by an average of more than1D, and refractive cylinder decreased by about1D. The major indication for the use of CXL is to inhibit the progression of corneal ecstasies, such as keratoconus and pellucid marginal degeneration. CXL may also be effective in the treatment and prophylaxis of iatrogenic keratectasia, resulting from excessively aggressive photo ablation. This treatment has also been used to treat infectious corneal ulcers with apparent favorable results. Most recent studies demonstrate the beneficial impact of CXL for iatrogenic ecstasies, pellucid marginal degeneration, infectious keratitis, bullous keratitopathy and ulcerative keratitis. Several long-term and short-term complications of CXL have been studied and documented. The possibility of a secondary infection after the procedure exists because the patient is subjected to epithelial debridement and the application of a soft contact lens. Formation of temporary corneal haze, permanent scars, endothelial damage, treatment failure, sterile infiltrates, bullous keratopathy and herpes reactivation are the other reported complications of this procedure. The primary treatment objective for CXL is to stabilize the underlying disease process by strengthening the stromal collagen network in order to delay or defer the need for corneal transplant. The advantage of CXL is that it is a minimally invasive treatment that can be performed on an outpatient basis. The main objectives for this evidence review were to determine the safety and effectiveness of CXL for the management of corneal thinning disorders.