Corneal topography, arcuate keratotomy, and compression sutures for astigmatism after penetrating keratoplasty

BACKGROUND: Twenty (20) patients with post-penetrating keratoplasty (PKP) (21 eyes) and excessive corneal astigmatism were studied using corneal topography to determine placement of arcuate incisions and compression sutures for astigmatism reduction. METHODS: Keratoplasty wounds and compression sutures were placed asymmetrically based on corneal topography only. Incisions were at the donor-host junction at a depth of 500 microns. RESULTS: A 56% reduction in corneal astigmatism was accomplished with an average cylinder reduction of 5.3 D. Keratometry readings were reduced in 18 of 20 (90%) of eyes and refractive cylinder was reduced in 15 of 20 (75%) of eyes. Corrected visual acuity improved in 15 of 20 (75%) declined in 15%, and did not change in 10%. CONCLUSION: Visual acuity can be improved by manipulating the astigmatism after penetrating keratoplasty using corneal topography maps to determine placement of arcuate incisions and compression sutures.