RELAXING INCISIONS WITH COMPRESSION SUTURES FOR CONTROL OF ASTIGMATISM AFTER PENETRATING KERATOPLASTY

Background: Ten per cent of patients with persisting postoperative ast igmatism following penetrating keratoplasty (PK) require surgical re-i ntervention, despite an otherwise ''successful'' transplant. Relaxing incisions (RIs) in combination with compression sutures seem to be the preferable procedure. However, poor predictability and lack of long-t erm experience complicate the issue. Here we report the 2-year follow- up results of 25 patients with high PK astigmatism treated by means of RIs and compression sutures Methods: Commonly, free-handed RIs were p laced at the graft-host interface and 10-0 nylon compression sutures w ere placed perpendicular to the incisions. PK sutures had been removed no less than 4 months prior to refractive surgery Results: Nineteen e yes regained a functional vision of greater-than-or-equal-to 0.4. The net decrease in astigmatism was 6.1 +/- 4.3 D (47 +/- 21 %). The mean vector-corrected change in astigmatism was 13.1 +/- 5.7 D. Cylinder ax is variation was reasonably low, with a correlation of attempted versu s achieved axis of r = 0.85. Within the first 3 months after operation the induced astigmatism regressed by, on average, 5.5 +/- 4.3 D, maki ng intraoperative overcorrection necessary. As an inevitable side effe ct, refractive procedures resulted in a myopic shift (4.7 +/- 6.9 D) i n spherical equivalence Conclusion: RIs and compression sutures are ve ry useful in reducing postkeratoplasty astigmatism if correction of ex tremely high cylinder (> 10 D) is not intended. However, predictabilit y still remains unsatisfactory and more than one operation may be requ ired.