Pyramidal aberrometry in wavefront-guided myopic LASIK: latest results
Session Details
Session Title: LASIK & PRK I
Session Date/Time: Sunday 15/09/2019 | 16:30-18:00
Paper Time: 16:48
Venue: Free Paper Forum: Podium 3
First Author: : A.Frings GERMANY
Co Author(s): : B. Allan
Abstract Details
Purpose:
Pyramidal aberrometry has greater sampling density and a higher dynamic range than Hartman Shack Aberrometry. Here we present measurement repeatability data and treatment results for a pyramidal aberrometer in routine myopic LASIK.
Setting:
Moorfields Eye Hospital, London
Methods:
3 consecutive aberrometry scans were acquired for 52 consecutive cases (104 eyes) treated with myopic wavefront-guided LASIK using the Amaris 1050rs excimer laser and Peramis pyramidal aberrometer (Schwind Eye-Tech Solutions GmbH, Kleinostheim, Germany). Random-effects ANOVA was used to derive a standard deviation within measures and limits of repeatability for the aberrometric refraction spherical equivalent (SE). Standard outcome reporting was used in analysis of manifest SE results of treatment, and a multiple regression model was used to derive nomogram adjustments to the attempted spherical correction.
Results:
The 95% repeatability coefficient for the preoperative aberrometric SE was 0.32D. The mean aberrometric SE was approximately 0.17D lower than the manifest refraction SE for the same patients, suggesting good control over accommodation during scanning. 94% were within ±0.50D of the intended target SE, and 91% had UDVA≤0.00 logMAR (≥20/20).
Regression modeling suggested systematic adjustments to the treatment sphere taking account of the attempted aberrometric SE and the difference between the manifest refraction SE and the aberrometric SE.
Conclusions:
Spherical equivalent measurement repeatability in pyramidal aberrometry may be better than for manifest refraction, suggesting myopic LASIK results could be improved by using wavefront guided treatment routinely.
Financial Disclosure:
None
