Postoperative suture manipulation for control of corneal graft astigmatism

Purpose: To assess the effect on post-keratoplasty astigmatism of postopera tive manipulation of a single running suture. Methods: Ail corneal transplant patients in whom a single 10/0 nylon runnin g suture was placed between November 1990 and April 1996 were included in a prospective study of the effect of manipulation of the suture at the earli est possible time after surgery when the keratometry became possible by vir tue of the epithelial surface integrity and where this revealed astigmatism of greater than 2D. Results: One hundred and ninety eyes underwent suture manipulation and were followed up. Follow up on 30 eyes was discontinued. Repeat manipulation of the running suture was the most common reason for discontinuation of follo w up. The remaining patients were followed For a mean (+/- SD) 415.5 +/- 32 6.4 days. Mean astigmatism of 7.8 +/- 3.1 D was reduced to 1.7 +/- 2.0 D im mediately after manipulation, but regressed to 3.0 +/- 1.9 D (n = 76) by ye ar. The suture was removed in 32 patients. Twenty-five eyes had post-remova l astigmatism measurements. In these 25 eyes, astigmatic error appeared not to revert to premanipulation levels. The only significant complication was one broken suture at manipulation, Conclusions: Early suture manipulation is effective in reducing suture in p ost-keratoplasty astigmatism, but some regression is seen.