Long-term results of single continuous suture adjustment to reduce penetrating keratoplasty astigmatism.

PURPOSE

To evaluate the long-term effect of single continuous corneal suture adjustment on reducing penetrating keratoplasty astigmatism after suture removal.

METHODS

Patients were identified from the original study of single continuous penetrating keratoplasty suture adjustment to reduce corneal astigmatism who were followed for more than a year after suture removal. A matching unadjusted control group was selected in the same way from those patients in the original study undergoing penetrating keratoplasty during the 2 years before the development of suture adjustment. The corneal astigmatism was compared before adjustment (study group) or <3 months after surgery (control group), >4 months after suture adjustment, and >12 months after suture removal in both groups.

RESULTS

A study group of 54 patients with suture adjustment and a control group of 45 patients without suture adjustment were identified. Before suture adjustment, the study group had an average keratometric astigmatism of 6.44 diopters (standard deviation [SD] = 2.51, range = 0.38-12.25), and the control group had 6.38 diopters (SD = 3.29, range = 2.75-16.00, p = 0.536). Compared to that in the unadjusted control group, the average penetrating keratoplasty astigmatism in the suture-adjusted group was reduced by 44.6% (2.36 diopters) 4.5 months after surgery and before suture removal (p = 0.0002) and by 25.4% (1.19 diopters) at least 12 months after suture removal (p = 0.011).

CONCLUSION

Postoperative adjustment of a single continuous corneal suture significantly reduces penetrating keratoplasty astigmatism after suture removal.