Corneal ring segments (INTACS) for the treatment of asymmetrical astigmatism of the keratoconus. Follow-up after 2 years

Abstract

Objective: To evaluate the use of corneal ring segments (INTACS) for the treatment of asymmetrical astigmatism in keratoconus. Material and methods: This prospective study involved nine eyes of seven patients who were operated on between December 1998 and June 2000. A case of keratoconus with opacified cornea was excluded from this study. The patients chosen were contact lens-intolerant. The surgical intervention was carried out under topical anesthesia. The INTACS (Addition Technology) corneal ring insert was inserted approximately 68% of the peripheral corneal depth and was centered to the cone of the cornea. Results: No intraoperative complications occurred. We noted a flattening of the central cornea and a decrease in irregular astigmatism for all patients. Mean preoperative uncorrected visual acuity was less than 1/10. Postoperatively two eyes had an uncorrected visual acuity of 10/10 seven eyes showed an improvement from an uncorrected visual acuity of 2/10 to 7/10. Conclusion: We have observed that the flattening effect of INTACS inserts on the soft corneal keratoconic tissue and on the high astigmatic tissue seems greater than that produced in normal cornea. Implantation of INTACS resulted in a significant reduction in asymmetrical astigmatism of the keratoconus.