Influence of ocular residual astigmatism on the correction of high compound astigmatism and myopic astigmatism using wavefront-guided LASIK
Session Details
Session Title: Presented Poster Session: Keratorefractive Results I
Venue: Poster Village: Pod 2
First Author: : J.Costa PORTUGAL
Co Author(s): : L. Figueiredo F. Neves R. Rothwell C. Arede
Abstract Details
Purpose:
To evaluate the influence of the ocular residual astigmatism (ORA) on the refractive and the higher order aberrations (HOA) outcomes in patients with high compound astigmatism and myopic astigmatism treated with LASIK using Zyoptix® Personalized Treatment Advanced.
Setting:
Department of Ophthalmology of Centro Hospitalar Vila Nova de Gaia/Espinho, Portugal.
Methods:
This retrospective study included 37 patients (52 eyes) with astigmatism higher than 2.75D and less than 2.00D sphere submitted to LASIK (Zyoptix® Personalized Treatment Advanced, Technolas217z100® system-Bausch&Lomb). The ORA was determined by vector analysis using refractive cylinder and topographic astigmatism. Patients were divided into two groups based on the ORA (ORA >mean - high ORA group; ORA ≤mean - low ORA group). The patients were also divided into two groups based on the value of the ratio ORA/anterior corneal astigmatism (ACA). Efficacy was determined by comparing the index of success and the HOA between the groups, 3 months after surgery.
Results:
The mean preoperative cylinder, ORA and ORA/ACA were -2.26±0.66D, 0.75±0.86D and 0.45±0.50D, respectively. The mean residual refractive cylinder postoperatively was -0.29±0.48D. No correlation was found between ORA, ORA/ACA and the refractive cylinder postoperatively. Mean indices of success in the high and low ORA groups were 0.19 and 0.13, respectively (P=0.12); in the high and low ORA/ACA groups were 0.18 and 0.14, respectively (P=0.37). A correlation between ORA, ORA/ACA and the index of success was found (Spearman,p<0.05).The HOA variation after LASIK showed no significant differences between groups; no correlation was found between ORA, ORA/ACA and HOA.
Conclusions:
Despite the correlation found between ORA, ORA/ACA and the index of success, the evaluation of the efficacy of astigmatic correction by LASIK using Zyoptix® Personalized Treatment Advanced showed no differences when the patients were divided according to the ORA and the ORA/ACA. Besides that, the ORA and the ORA/ACA had no influence on the HOA outcomes.
Financial Disclosure:
NONE