Keratoprosthesis: a 12-year follow-up.

A retrospective study of our total experience with implantation of four types of keratoprosthesis in 125 cases was reviewed. Diagnoses in the cases treated included chemical burns, derangement of the anterior segment from disease or injury, aphakic bullous keratopathy, ocular pemphigoid, Stevens-Johnson syndrome, anterior cleavage syndrome, Mooren ulcer, and blast injuries. The visual results in some cases have been gratifying and in others heartrending. Thirty percent of the patients attained 20/15 to 20/40 visual acuity, but at the end of 12 years, only 13% still had this visual acuity. Twenty-four percent attained 20/50 to 20/200 visual acuity, but this figure fell to 17% at the end of 12 years. Loss of initial good visual acuity was due to the numerous complications which required close observation and repeated surgery to control. The number of complications has been reduced by the use of a keratoprosthesis with a Dacron skirt and of the addition the Cardona nut and bolt to the shaft. The surgical technique has been improved by the use of a scleral expander, elimination of a scleral graft, and the use of the Tenon graft. The indications for the keratoprosthesis have changed over the years. Many alkali burns and practically all aphakic bullous keratopathy have been eliminated from the indications. Keratoprosthesis should be reserved for desperate cases. The technique of implantation is not complicated and initial results are usually good. The multiple complications, however, make it necessary for these cases to be followed by a surgeon who is familiar with the management of complications.