Impact of increased PTA values on visual outcomes one year after refractive lenticule extraction (ReLEx SMILE)

Session Details

Session Title: Refractive
Session Date/Time: Friday 10/02/2017 | 10:30-12:30
Paper Time: 11:06
Venue: Brussels Room 0.4

First Author: D.Breyer GERMANY
Co Author(s): H. Kaymak  K. Klabe  P. Hagen  F. Kretz  G. Auffarth     

Abstract Details

Purpose:

Former studies showed comparable visual recovery and aberrometric results for the ReLEx smile and Femto-LASIK. For LASIK, however, there is evidence that PTA (Percent Tissue Altered) values >40% can be seen as a contributing factor in the development of keratectasia. This retrospective analysis addresses the question whether this also holds for increased PTA values in case of ReLEx SMILE.

Setting:

All ReLEx SMILE (VisuMax, CZM) surgeries were performed at the Breyer-Kaymak-Klabe Eyesurgery in Duesseldorf, Germany, which is part of the International Vision Correcton Research Center (IVCRC.net).

Methods:

We analyzed the impact of high PTA-values by comparing the results of 2 ReLEx smile groups; 350 eyes with PTA<40% and 350 eyes with PTA>40%. Follow up was performed between 1 day and up to 36 month postoperatively. Results were evaluated in terms of visual acuity, manifest refraction and wave front analysis (KR-1W, Topcon). Development of Ectasia was assessed using difference maps of corneal reference surfaces from Scheimpflug tomography (Belin-Ambrosio Enhanced Ectasia Display, Pentacam, Topcon).

Results:

Overall PTA values ranged from 29% to 53%. We could not detect significant differences between the two PTA-groups (<40% and >40%) in terms of safety, predictability and visual recovery. All groups showed a mean monocular UDVA of <0.05 LogMAR one year after treatment. Furthermore, no significant differences in ectasia difference maps were found between the two PTA-groups.

Conclusions:

For ReLEx smile our results do not provide evidence for keratectasia development for cap thicknesses of 150ﾵm and PTA values above 40%.

Financial Disclosure:

receives consulting fees, retainer, or contract payments from a company producing, developing or supplying the product or procedure presented, travel has been funded, fully or partially, by a competing company, travel has been funded, fully or partially, by a company producing, developing or supplying the product or procedure presented, receives consulting fees, retainer, or contract payments from a competing company