Advanced analysis of topography-guided LASIK treatment planning strategies
Session Details
Session Title: LASIK I
Session Date/Time: Sunday 23/09/2018 | 14:00-16:00
Paper Time: 14:52
Venue: Room A3, Podium 2
First Author: : R.Krueger USA
Co Author(s): : V. De Stefano C. Meister G. Ehlke
Abstract Details
Purpose:
Since the U.S. approval of topography-guided customized treatments (TCAT), much debate has ensued regarding the appropriate planning strategies when manifest and topographically measured cylinder values differ in axis and magnitude. We wish to analyze our pattern of success among the eyes that gained one or more lines of best corrected visual acuity (BCVA).
Setting:
Cleveland Clinic Cole Eye Institute
Methods:
256 eyes undergoing TCAT by a single surgeon from Feb 2016 to May 2017 were enrolled. All eyes were healthy, without previous refractive surgery, and had at least 4 good quality topographic maps. Corneal shape was captured with the Topolyzer, and coupled with refraction to generate an ablation profile with the Allegretto Wave Eye-Q laser. The cylinder magnitude and axis of laser entry were decided by the surgeon, based on both the manifest and measured values, assisted by additional data from a tomographer (Pentacam) and ocular wavefront (LADARWave). All patients were followed at 1 day, 1 week and 3 months.
Results:
At three months, 95.7% achieved UDVA of 20/20 or better, while 81.4% were 20/15 or better. 25.6% gained one or more lines of BCVA. Among these eyes, measured and manifest axis differed by less than 15° in 59%, between 15° and 30° in 18% and more than 30° in 23%. When it differed by at least 5°, the measured axis was treated in 79%, 67% and 73% of eyes, respectively. In over 2/3 of eyes, where magnitude of measured cylinder was greater, 75% of these were treated between manifest and measured values, with only 7% at the full measured value.
Conclusions:
TCAT can achieve better than glasses vision in more than a quarter of eyes. In eyes gaining a line of vision, the measured axis is treated in 75%. When the measured magnitude is higher, a value between the measured and manifest is chosen in 75% to avoid overcorrection. Tomography and ocular wavefront values assist in the selection process.
Financial Disclosure:
... receives consulting fees, retainer, or contract payments from a company producing, developing or supplying the product or procedure presented