DIFFERENT SUTURING TECHNIQUES VARIOUSLY AFFECT THE REGULARITY OF POSTKERATOPLASTY ASTIGMATISM

Objective: This study aimed to determine the effect of various suturin g techniques on the regularity of postkeratoplasty astigmatism. Design : A prospective clinical trial. Participants: Sixty-two consecutive pa tients undergoing penetrating keratoplasty by the same surgeon (MB) pa rticipated. Intervention: Each patient was assigned to one of four gro ups according to the suturing technique used (a = 16 interrupted 10-0 nylon sutures; b = 2 running 10-0 nylon sutures, each with 8 bites; c = 2 running 10-0 nylon sutures, each with 12 bites; d = 2 running 10-0 nylon sutures, each with 16 bites). This was the only parameter permi tted to be changed in the standard keratoplasty procedure used for all cases. Corneal topography was performed 1, 3, and 6 months after surg ery. The astigmatic patterns seen on the corneal maps then were classi fied into regular (symmetric or asymmetric bowtie patterns) or irregul ar (distorted bowtie, multiaxial, or other patterns). Main Outcome Mea sures: Regularity of postkeratoplasty corneal astigmatism was measured . Results: At all postoperative examination times, the percentage of i rregular astigmatic patterns was highest in group a and lowest in grou p d (chi-square test: P < 0.005), Groups b and c showed intermediate v alues. The entity of the astigmatic error as measured by the simulated K-readings of the topographic maps did not differ significantly in th e four groups. Conclusions: A suturing technique using 2 running sutur es with 16 bites each can minimize irregular postkeratoplasty astigmat ism as long as sutures are in place, when compared with interrupted su tures or double-running sutures of less than 16 bites.