Comparison of visual outcomes after wavefront-guided ablation and wavefront-optimized ablation for treating myopia with or without astigmatism

Session Details

Session Title: Photoablation Outcomes I

Session Date/Time: Monday 07/09/2015 | 16:30-18:30

Paper Time: 17:27

Venue: Room 17

First Author: : M.Khalifa EGYPT

Co Author(s): :    T. Masoud   M. Alsahn                 

Abstract Details

Purpose:

Comparison of the latest technology of wavefront-guided (WFG) ablation using Star S4IR excimer laser with iDesign aberrometer ( AMO) versus the latest technology of wavefront-optimized ablation using Allegretto EX-500 excimer laser with cyclotorsion ( Alcon).

Setting:

Horus vision Correction Center and Alex LASIK Center, Alexandria, Egypt

Methods:

A prospective, comparative masked study including 2 groups: WFG group: Visx Star S4 IR + iDesign WFG ablation (AMO) and WFO group: Allegretto EX-500 (Alcon) with WFO ablation with cyclotorsion registration. Each includes 150 myopic eyes with or without astigmatism which is subdivided into 3 subgroups; 1: 50 eyes with low myopia (MRSE -0.25 to3.0 D), 2: 50 eyes with moderate myopia (MRSE >-3.0 to -6.0 D), and 3 : 50 eyes with high myopia (MRSE>-6.0 D). Visual function is evaluated preoperatively, 1, 3, and 6 months after surgery. C.S. and HOA's are measured preop. and P.O. 6 months.

Results:

150 eyes in WFG group and 152 eyes in WFO group. Mean preop. MR -4.53±2.35 D in WFG and -4.55±2.35 D in WFO ( P=0.562). Cyclotorsion registration was enabled in 100% of WFG and 68.4% of WFO. Six months postop 94% and 74% of eyes were within ±0.5D of MRSE; efficacy indexes were 0.99±0.14 and 0.94±0.12 (p= 0.013) and 46% and 26% of eyes gained one or more lines of BCVA in the WFG and WFO groups respectively. The WFG group had statistically better performance in the correction of cylinder (0.0071), induction of spherical aberration (P=0.0001) and HOA (P=0.0287).

Conclusions:

Wavefront guided and Wavefront optimized ablations are effective, safe, and predictable in treating myopia with or without astigmatism. But, WFG ablations using the iDesign system for treatment planning provide higher efficacy, predictability and safety, and more patients with 1.2 UCVA through better handling of HOA's, better cylinder correction, and better axial and torsional alignment.

Financial Interest:

One of the authors research is funded, fully or partially, by a company producing, developing or supplying the product or procedure presented