Relaxing Incisions Combined With Adjustment Sutures for Post-Deep Anterior Lamellar Keratoplasty Astigmatism in Keratoconus

Abstract

To find an effective and reliable method to correct astigmatism after deep anterior lamellar keratoplasty (DALK) in patients with keratoconus. This interventional case series included 14 eyes of 14 patients with keratoconus (12 males) undergoing graft refractive surgery (GRS) for intolerable post-DALK astigmatism. The technique of GRS for the 5 initial cases consisted of only relaxing incisions at the steep meridian in the graft-host interface down to Descemet membrane. For the rest, the relaxing incisions at the steep meridian were accompanied by simultaneous suturing and the effect of the relaxing incisions was controlled through selective suture removal starting a few days after the operation. The main outcomes were uncorrected and corrected visual acuity and change in refractive and keratometric astigmatism using subtraction and vector analysis methods. Mean patient age was 29.36 +/- 6.2 years. Mean time interval from complete suture removal to GRS and follow-up period were 4.5 +/- 2.0 months and 12.0 +/- 7.4 months, respectively. Mean preoperative best-corrected visual acuity was 0.29 +/- 0.1, increasing to 0.22 +/- 0.1 logarithm of minimum angle of resolution after the operation (P = 0.007). Average keratometric astigmatism was reduced by 3.8 and 5.5 diopters measured with subtraction and vector analysis methods, respectively. Four of 5 eyes that had only relaxing incisions initially required suturing of the incisions because of overcorrection, whereas preliminary results showed none of the 9 patients undergoing simultaneous relaxing incisions and suturing required further intervention. Relaxing incisions and suturing at the steep meridian followed by selective suture removal can effectively and predictably reduce post-DALK astigmatism in patients with keratoconus.