Keratometric astigmatism after suture removal in penetrating keratoplasty - Double running versus single running suture techniques

Background and Objective: To compare astigmatism after suture removal in a retrospective sequential series of patients who had penetrating keratoplasty with either a double running suture technique or an adjustable single running suture technique. During the first year post-keratoplasty, when sutures were in place, the latter technique had produced less astigmatism. Materials and Methods: Keratometry and keratometric astigmatism were measured before and after suture removal. We compared these variables in 30 grafts with the double running suture technique to the same variables in 24 grafts with the single running suture technique. Results: The final portion of the double running suture was removed 408 +/- 177 (mean +/- SD) days after keratoplasty, whereas the single running suture was removed 611 +/- 224 days after keratoplasty (P < 0.001). After suture removal, there was no difference between the double running and single running groups in either mean keratometry [46.5 +/- 1.8 diopters (D) versus 45.6 +/- 2.0 D, P = 0.09, minimum detectable difference (MDD) = 1.5D] or mean astigmatism (4.6 +/- 2.7 D versus 5.2 +/- 3.2D, P = 0.72, MDD=2.3). Conclusion: In this consecutive series of corneal transplants performed by one surgeon, the results suggest no difference in astigmatism between the two suturing techniques after all sutures have been removed.