Perforating keratoplasty with an intracorneal ring

Purpose. We evaluated the clinical feasibility of an intracorneal ring for penetrating keratoplasty (PKP) designed to decrease postoperative corneal a stigmatism Material and Methods. A steel alloy ring was used for 8-mm PKP. The prospective study was comprised of 15 consecutive patients who underwen t PKP for different corneal pathologies. The mean age was 52 years (range, 20-74 years). The Guided Trephine System was used in all cases for the prep aration of the donor button and the recipient bed to ensure identical dimen sions. The donor button with the surrounding ring in place was sutured in p lace with a 10-0 nylon double-running suture. Results. Except for one patie nt who had an allergic reaction to alloy components, no significant complic ations were observed. Mean reepithelialization occurred within an average o f 4 days (range, 3-5 days). In 80% of the cases, stromal graft edema and De scemet's folds disappeared at 14 days after surgery. Average removal time o f the intracorneal ring was 6 months (range, 3-9 months). Mean corneal asti gmatism was 2.71 (standard deviation [SD], 1.37) diopters (D) before surger y compared to 2.10 (SD, 1.09) D at 1 month, 2.07 (SD. 1.26) D at 3 months, 2.29 (SD, 0.86) D at 6 months, and 2.94 (SD, 1.05) D at 12 months. In four eyes (27%), ruptures of one of the double-running antitorque sutures requir ed resuturing. Conclusion. The intracorneal ring prevented the donor button from distortions related to peripheral changes or suture traction. A sutur ed intracorneal ring appears to be a safe and effective aid in keratoplasti es. Further evaluation in a multicenter study with larger patient numbers a nd indication-specific longer follow-ups is under way.