Astigmatic keratotomy after keratoplasty

We reviewed the results of astigmatic keratotomy in 12 eyes after keratoplasty. Penetrating keratoplasty had been performed in 11 eyes and lamellar keratoplasty in one. Arcuate keratotomy with 7mm in optical zone was performed. The procedure was repeated twice in 4 eyes. Following keratotomy, manifest astigmatism decreased from 6.47 ± 2.10 D to 3.77 ± 2.28 D and the keratometric astigmatism from 7.67 ± 1.92 D to 3.64 ± 2.00 D. The changes were significant. The differences between the intended and the induced astigmatism as calculated by vector analysis were within ±2 diopters in only 7 eyes, 47%. Overcorrections resulted in the other 5 eyes including 3 eyes of severe overcorrection. Two of the 3 eyes needed further surgical correction. The findings show that astigmatic keratotomy is effective for reducing astigmatism in eyes after keratoplasty but that predictability is relatively poor. We advocate the procedure to eyes with high astigmatism with severely impaired visual function following keratoplasty. It is also advised to aim at an undercorrection.