Relaxing incisions for postkeratoplasty astigmatism.

We report 100 cases of postkeratoplasty astigmatism, ranging from 4 to 20.5 diopters, treated with the following procedures: relaxing incisions, relaxing incisions with augmentation sutures, and repeated relaxing incisions with augmentation sutures according to the degree of astigmatism. Patients were divided into three study groups (group 1 for preoperative defects ranging from 4 to 10 diopters, group 2, from 10.5 to 15 diopters, and group 3 for defects exceeding 15 diopters). Mean preoperative astigmatism was 7.15 +/- 1.67, 12.56 +/- 1.37, and 17.50 +/- 1.51 diopters in each group, respectively. The net decrease in astigmatism after surgery was 5.53 +/- 1.44, 9.68 +/- 1.80, and 14.87 +/- 1.69 diopters in each group, respectively. Postoperatively, spectacle-corrected visual acuity improved by two Snellen lines in the group 1, five in the group 2, and nine in the group 3. The mean time to achieve stable results after surgery was 2.2 +/- 0.3, 2.7 +/- 0.4, and 4.2 +/- 0.7 months in each group, respectively (two patients in group 2 and all patients in group 3 underwent a two-step procedure). The relaxing incisions procedure, eventually modified by either adding compression sutures or repeating the incisions after 8-10 weeks, offers the possibility of a wide range of corrections for postkeratoplasty astigmatism with acceptable postoperative periods for visual rehabilitation.