Contact lenses and corneal deformation: cause, correlate or co-incidence?

. Sporadic reports describing cases of corneal deformation (i.e. corneal warpage with astigmatism or keratoconus) after a minimum of about 4 years' contact lens wear are condensed into Table 1. Some severe cases required corneal grafting. Eight personal cases are described in Table 2, including two who have worn only soft lenses and one who has worn soft lenses for 6 out of 7 years. It is suggested that although some cases of this corneal distortion might well have occurred without contact lenses, the trauma of years of contact lens wear is causative if the individual's cornea is predisposed, possibly by the carrier state of hereditary naturally-occurring keratoconus. A risk-averse patient and practitioner would probably add this to other possible complications, and restrict contact lenses to eyes with more severe refractive errors, and minimise the wearing time.