Abstract
Purpose: :
Postoperative visual rehabilitation after penetrating keratoplasty may be negatively affected by high degrees of anisometropia particularly astigmatism which is often irregular and cannot be satisfactorily corrected with glasses or contact lenses. The aim of the present study was to assess the efficacy, accuracy and safety of topography-guided laser-assisted subepithelial keratectomy (LASEK) with mitomycin C (MMC) in patients with irregular astigmatism after penetrating keratoplasty using the Allegretto wave eye-Q laser.
Methods: :
9 eyes of 6 patients with high irregular astigmatism after penetrating keratoplasty which could not be adequately corrected with glasses or contact lenses were included in this study. After repeated evaluation of corneal topography using the Wavelight Oculyzer all patient were treated with LASEK using the T-CAT software (topography-guided customized ablation treatment) of the Allegretto wave eye-Q laser platform. Immediately after laser ablation MMC (0.02%) was applied to the corneal surface for 20 seconds. Maximum correction of astigmatism was limited to 6.0 diopters.
Results: :
Mean follow up was 11 + 3 months. The mean preoperative spherical equivalent (SE) decreased from -4.54 + 1.8 (SD) diopters (D) to -1.67 + 1.0 D (P<0.005) postoperatively. The mean preoperative cylinder decreased from -6.70 + 1.9 D to -2.05 + 0.8 D (P<0.0005). All eyes gained at least one line, 7 eyes 2 lines and 2 eyes 3 lines of best spectacle corrected visual acuity. In 2 patients only small amounts of haze (grade 1) were observed postoperatively. Moreover, all patients could be satisfactorily corrected with glasses after topography-guided laser ablation.
Conclusions: :
In the present study we could show that topography-guided laser-assisted subepithelial keratectomy with MMC using the Allegretto wave eye-Q laser platform is an effective treatment in patients with irregular astigmatism after penetrating keratoplasty
Keywords: astigmatism • refractive surgery • laser