Femtosecond laser arcuate keratotomy for the correction of postkeratoplasty high astigmatism in keratoconus

Abstract

Background: Astigmatism is the leading complication in visual recovery after penetrating keratoplasty (PKP) and deep anterior lamellar keratoplasty (DALK); in this study, we evaluated the outcome of femtosecond laser arcuate keratotomy (FLAK) after DALK and PKP in Iranian keratoconic patients. Materials and Methods: In this prospective interventional case series, refractive and keratometric predictability, efficacy, and complications of FLAK for postkeratoplasty astigmatism in keratoconus were evaluated; 23 eyes of 23 consecutive patients (mean age of 32.43 ± 9.11 years) with high astigmatism were enrolled. The femtosecond laser performed paired 90°?angled arcuate incisions. Results: Mean logarithm of the minimum angle of resolution of corrected and uncorrected visual acuity improved from preoperative values of 0.30 ± 0.18 and 0.85 ± 0.32 to 6?month values of 0.19 ± 0.17 and 0.65 ± 0.33, respectively (P < 0.05). Mean subjective astigmatism was 7.79 ± 2.64 diopter (D) preoperatively and 3.69 ± 2.25D at 6?month after surgery (P < 0.05). Surgically induced astigmatism was 9.27 ± 5.00D. Mean refractive spherical equivalent showed no significant (P = 0.69) hyperopic shift from ? 4.21 ± 4.84D preoperatively to ? 2.16 ± 6.09D postoperatively. Two (8.7%) microperforations were observed. Conclusion: FLAK is a relatively safe and effective method for the treatment of postkeratoplasty astigmatism.

Key words: Astigmatic keratotomy, deep anterior lamellar keratoplasty, femtosecond laser, keratoconus, keratoplasty, penetrating keratoplasty