Keratoconus is a disease that affects the stability and structure of the cornea. Early in the disease patients may notice that vision has been changing frequently and that vision doesn't seem as clear as it could be. Eventually the ability to get clear vision with glasses is lost and contact lenses are needed for full correction. Instruments such as the corneal topographer aid us in the diagnosis and fitting of contact lenses in this situation. Specially designed lenses can be made to increase the vision.