Comparison of Visual Outcomes of Wavefront-Guided Ablation Versus Wavefront Optimized Ablation in Treating Myopia With or Without Astigmatism

Monday, April 20, 2015: 3:31 PM
Room 1A (San Diego Convention Center)
Mounir A. Khalifa, MD, PhD
Tamer H. Massoud, MD, PhD
Mahmoud Elsahn, MD

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

A prospective, consecutive, multicenter, masked follow-up study which includes 2 gps: WFG gp: Star S4 IR + iDesign System wavefront-guided ablation (Abbott Medical Optics) and WFO gp: Allegretto EX-500 (Alcon) using an optimized ablation. Each group includes 150 myopic eyes with or without astigmatism which is subdivided into 3 subgroups; subgroup 1 : 50 eyes with low myopia (MRSE -3.0 D), subgroup 2 : 50 eyes with moderate myopia (MRSE >-3.0 to -6.0 D), and subgroup 3 : 50 eyes with high myopia (MRSE>-6.0 D). Visual function is evaluated preoperatively, 1 month, and 3 months after surgery. Contrast sensitivity and HOA’s are measured preoperatively and P.O. 3 months.

Preliminary results include 51 eyes in WFG gp and 54 eyes in WFO gp. Mean preop. MR -4.250±2.062 D in WFG and -4.168±2.065 D in WFO without significant difference ( P=0.22). Cyclotorsion registration was enabled in 100% of WFG and 81.5% (44 eyes) of WFO. No significant difference in efficacy, safety, predictability, and stability. WFG was significantly better in UCVA > 1.0 ( P-0.003), in eyes gained 2 lines or more ( P=0.006), P.O.cylinder (P= 0.00016), induced HOA’s (P-0.05), spherical aberration (P=0.02), and coma (P=0.03).  CS showed no significant difference except in 18 c/d (P= 0.031). Complete results with subgroups analysis will be presented at the meeting.

Wavefront-guided and wavefront optimized ablations are highly effective, safe, and predictable in treating myopia with or without astigmatism. But WFG ablations offer more supervision through better handling of HOA’s, better cylinder correction, and better axial and torsional alignment.