TY - JOUR
T1 - Ocular aberrations measured by the fourier-based waveScan and zernike-based LADARwave hartmann-shack aberrometers
AU - Knapp, Stefanie
AU - Awwad, Shady T.
AU - Ghali, Claudine
AU - McCulley, James P.
N1 - Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2009/2
Y1 - 2009/2
N2 - PURPOSE: To evaluate agreements in lower and higher order aberration measurements by two Hartmann-Shack wavefront-sensing devices. METHODS: Using the VISX WaveScan and Alcon LADARWave aberrometers, ocular aberrations at a fixed optical zone of 6 mm were measured on 36 eyes of 18 patients. A tunable light intensity source was used to control pupil size, which was checked using infrared pupillometry. Repeatability of measurements was evaluated using the intra-class correlation coefficient with 3 consecutive measurements on each aberrometer. RESULTS: Mean absolute defocus for WaveScan and LADARWave was 2.82±2.69 and 2.93±3.24 rootmean-square (RMS) μm, whereas astigmatism was 0.81±0.49 and 0.87±0.57 μm, respectively. Pearson correlation coefficients between the two aberrometers were 0.908 and 0.870 for defocus and astigmatism, respectively, whereas higher order aberration correlation was less tight (Pearson correlation coefficient=0.596 for coma, 0.746 for trefoil, 0.836 for spherical aberration, 0.637 for secondary astigmatism, and 0.963 for quadrafoil [P<.001 for all]). The LADARWave had a tendency to display more spherical aberration than the WaveScan, especially at high aberration values, with mean absolute difference in measurement of 0.12±0.08 μm, and only 44% of eyes having less than ±0.10 RMS pm of difference. The mean total higher order aberration absolute difference was 0.14±0.14 μm, with only 50% of eyes within ±0.1 RMS of agreement. Vector analysis revealed appreciable discrepancies in third- and fourth-order directional Zernike components, while showing similar values for fifth-order components. Intra-class correlation coefficient values for both aberrometers over different aberration orders showed excellent repeatability. CONCLUSIONS: The WaveScan and LADARWave share similar lower order aberration measurements, but display significantly different higher order aberration values.
AB - PURPOSE: To evaluate agreements in lower and higher order aberration measurements by two Hartmann-Shack wavefront-sensing devices. METHODS: Using the VISX WaveScan and Alcon LADARWave aberrometers, ocular aberrations at a fixed optical zone of 6 mm were measured on 36 eyes of 18 patients. A tunable light intensity source was used to control pupil size, which was checked using infrared pupillometry. Repeatability of measurements was evaluated using the intra-class correlation coefficient with 3 consecutive measurements on each aberrometer. RESULTS: Mean absolute defocus for WaveScan and LADARWave was 2.82±2.69 and 2.93±3.24 rootmean-square (RMS) μm, whereas astigmatism was 0.81±0.49 and 0.87±0.57 μm, respectively. Pearson correlation coefficients between the two aberrometers were 0.908 and 0.870 for defocus and astigmatism, respectively, whereas higher order aberration correlation was less tight (Pearson correlation coefficient=0.596 for coma, 0.746 for trefoil, 0.836 for spherical aberration, 0.637 for secondary astigmatism, and 0.963 for quadrafoil [P<.001 for all]). The LADARWave had a tendency to display more spherical aberration than the WaveScan, especially at high aberration values, with mean absolute difference in measurement of 0.12±0.08 μm, and only 44% of eyes having less than ±0.10 RMS pm of difference. The mean total higher order aberration absolute difference was 0.14±0.14 μm, with only 50% of eyes within ±0.1 RMS of agreement. Vector analysis revealed appreciable discrepancies in third- and fourth-order directional Zernike components, while showing similar values for fifth-order components. Intra-class correlation coefficient values for both aberrometers over different aberration orders showed excellent repeatability. CONCLUSIONS: The WaveScan and LADARWave share similar lower order aberration measurements, but display significantly different higher order aberration values.
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U2 - 10.3928/1081597x-20090201-05
DO - 10.3928/1081597x-20090201-05
M3 - Article
C2 - 19241771
AN - SCOPUS:60849086495
SN - 1081-597X
VL - 25
SP - 201
EP - 209
JO - Journal of Refractive Surgery
JF - Journal of Refractive Surgery
IS - 2
ER -