graft refractive surgery for post-dalk atigmatism in keratoconus

purpose: evaluate the effect of relaxing incision and adjustment sutures to correct astigmatism after deep anterior lamellar keratoplasty (dalk) in patients with keratoconus. materials and methods: this interventional case series included keratoconic eyes undergoing graft refractive surgery (grs) for intolerable post-dalk astigmatism. the technique of graft refractive surgery for the 5 initial cases consisted of relaxing incisions at the steep meridian in the graft-host interface down to descemet’s membrane. the main outcomes were uncorrected and best-corrected visual acuity, and change in refractive and keratometric astigmatism using subtraction and vector analysis methods. results: fourteen eyes of 14 keratoconic patients (12 male subjects) with history of dalk underwent grs. mean age of the patients was 29.36±6.2 years and mean follow-up period was 12.0±7.4 months after initial grs. mean preoperative bcva was 0.29±0.1 logmar which improved to 0.22±0.1 logmar after the operation (p=0.007). average keratometric astigmatism was reduced by 3.8 d and 5.5 d as measured by subtraction and vector analysis methods, respectively. conclusion: 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