Abstract
Purpose: :
To evaluate the initial refractive change and the predictability of arcuate keratotomies (AK) and Ruiz procedures (Ruiz) in the treatment of post–graft astigmatism.
Methods: :
Retrospective cohort study. A total of 49 eyes were included, of which 23 eyes had AK and 26 had Ruiz performed. All patients had undergone previous penetrating keratoplasty and had similar group–specific surgical incisions. Preoperative and 3 months postoperative refractive data was collected and vector analysis was performed to study the surgical induced astigmatism.
Results: :
The preoperative mean cylinder was 7.13 D ± 2.54 D in the AK, and 8.75 D ± 3.05 D in the Ruiz group. The postoperative mean cylinder was 3.96 D ± 2.59D in the AK group and 5.31 D ± 3.12 in the Ruiz group, representing a reduction in cylinder of 44.5% and 39.3% respectively. Arcuate keratotomy induced a myopic shift of –0.46 D and Ruiz a hyperopic change of 1.95 D. 52% of the eyes in the AK and 38% in the Ruiz group were within ±1 D of the attempted cylinder correction. Vector analysis has been used for further outcome reporting.
Conclusions: :
Arcuate keratotomy and Ruiz procedures are effective treatment options for post–graft astigmatism. However the results can be quite unpredictable. Ruiz induced a significant hyperopic shift and is therefor more appropriate for patients with associated myopia and astigmatism.
Keywords: astigmatism • keratoprostheses • refractive surgery: other technologies