Comparison of Ocular Wavefront Aberration Measurements Obtained Using Two Hartmann–Shack Wavefront Aberrometers

Abstract

Objectives: To assess agreement between measurements of ocular wavefront aberrations obtained using the Pentacam AXL Wave (Oculus Optikgeräte GmbH) (Aberrometer A) and KR-1W (Topcon Corp) (Aberrometer B), both of which are based on the Hartmann-Shack principle. Methods: In this prospective case-control study, ocular wavefront aberrations measurements were obtained using both aberrometers in patients with keratoconus (KC) and control participants. Ocular wavefront aberrations were measured through the natural pupil without dilation using both devices in a dark room. For both aberrometers, accommodation was inhibited by automatically adding fogging. The individual Zernike coefficients from the second to fourth order were compared between the two aberrometers for a 4-mm pupil diameter. Results: Twenty-six KC and 29 control eyes were assessed. Statistically significant correlations (P,0.05) were observed for all Zernike coefficients, except for Z 4 22 in the control group. Bland-Altman analysis indicated good agreement between aberrometers and no statistically significant differences in the control group. However, in the KC group, patterns of proportional error were observed in vertical coma Z 3 21 (r¼0.338, P¼0.008), trefoil Z 4 24 (r¼0.701, P¼0.003), secondary astigmatism Z 4 22 (r¼0.348, P¼0.025), and spherical aberrations Z 4 0 (r¼0.407, P¼0.012). Conclusions:The Zernike coefficient values measured by the two aberrometers were well correlated in the control and KC groups. However, in eyes with KC, Aberrometer B tended to present greater values in several Zernike coefficients than Aberrometer A, suggesting that wavefront measurements obtained using the two aberrometers are not interchangeable in patients with KC.

Correction of Asymmetric Bowtie Corneal Astigmatism with a Toric Intraocular Lens: Outcomes and Accuracy of Measurement Modes

“…Asymmetric bowtie astigmatism can be seen as a combination of symmetric bowtie and coma, and only the former can be corrected by a toric IOL. The Hartman–Shack aberrometer is used in Pentacam to capture wavefront data at multiple locations [ 29 ]. The Hartman–Shack aberrometer has better repeatability than other sensor technologies [ 30 ].…”

A Comprehensive Wavefront Assessment of Keratoconus Using an Integrated Scheimpflug Corneal Tomographer/Hartmann–Shack Wavefront Aberrometer

“…Recently, several researchers have reported on the repeatability and agreement of the device used herein compared to other devices for wavefront measurement. [19][20][21][22][23] Thus far, there have been two reports on wavefront analysis in KC using this wavefront aberrometer, but both are simple comparisons with healthy eyes. 21,23 Consistent with the result of our previous investigation that used an integrated Placido-disk topography system with a Hartmann-Shack wavefront aberrometer, 15 wavefront properties generally correlated with KC severity classified based on clinical and topographic signs.…”

“…[19][20][21][22][23] Thus far, there have been two reports on wavefront analysis in KC using this wavefront aberrometer, but both are simple comparisons with healthy eyes. 21,23 Consistent with the result of our previous investigation that used an integrated Placido-disk topography system with a Hartmann-Shack wavefront aberrometer, 15 wavefront properties generally correlated with KC severity classified based on clinical and topographic signs. Contrary to our expectations that we would detect abnormalities in the posterior cornea, the comprehensive wavefront assessment in this study did not show significant differences in wavefront properties between the VAE-NT and control eyes.…”

“…Recently, several researchers have reported on the repeatability and agreement of the device used herein compared to other devices for wavefront measurement. 19–23 Thus far, there have been two reports on wavefront analysis in KC using this wavefront aberrometer, but both are simple comparisons with healthy eyes. 21,23…”

“…19–23 Thus far, there have been two reports on wavefront analysis in KC using this wavefront aberrometer, but both are simple comparisons with healthy eyes. 21,23…”