Limbus-parallel keratotomies and compression sutures in excessive astigmatism after penetrating keratoplasty

From 1986 to 1991, among 980 penetrating keratoplasties, all 22 patients were studied retrospectively who had undergone 28 refractive procedures because of high corneal astigmatism after penetrating keratoplasty. In 8 procedures, only relaxing incisions were made, and in 20 procedures, additional compression sutures were placed at 90 degrees to the former. In 7 cases the relaxing incisions were located on the patient's peripheral cornea and in 21 cases, inside the graft margin. The absolute preoperative corneal astigmatism was 7.25-20.0 D (mean, 11.5 +/- 3.1 D). Immediately after surgery it was 0-14.0 D (mean, 7.0 +/- 3.6 D). The vector-corrected astigmatism immediately after surgery was 1.0-28.9 D (mean, 13.2 +/- 7.8 D). After a mean follow-up of 20.6 months, the mean residual astigmatism was 1.0 +/- 11.25 D (mean, 5.4-2.5 D). The mean postoperative vector-corrected astigmatism was 0-19.3 D (mean, 9.1 +/- 4.6 D). The best-corrected preoperative visual acuity was 0.12-0.9 (mean, 0.4), the best postoperative visual acuity was 0.3-1.2 (mean, 0.6). The approach described may reduce disturbing postkeratoplasty astigmatism--although the predictability remains unsatisfactory.