Measurement of higher-order aberrations has changed from a laboratory or research application to a clinical application and may be used for example in wavefront-guided excimer laser surgery, lens implantation surgery, and contact lens fitting. It provides an estimation of the optical quality of the eye that extends beyond the description of spherical and cylindrical refractive errors. Wavefront analysis allows for a detailed evaluation of imperfections in the optical system of the eye, caused by the refractive surfaces of the anterior and posterior cornea and the lens. It would be worthwhile in the future to evaluate aberrometers in patients with more aberrant eyes. Hartmann-Shack aberrometers showed the best repeatability for total ocular aberrations and iTrace for corneal aberrations. Total ocular and corneal aberrations are not comparable when measured with different aberrometers. The OPD-Scan showed a lower interobserver variability, compared with the Irx3, Keratron, and iTrace. The repeatability of the corneal aberration measurements was highest for the iTrace, followed by the Keratron and OPD-Scan. The Irx3 showed the highest repeatability in measuring total ocular aberrations, followed by the Keratron, OPD-Scan, and iTrace. Significant differences in measurements were found for several total ocular aberrations (defocus, astigmatism, trefoil, trefoil, and spherical aberration ) and corneal aberrations (defocus and astigmatism ). Second-, third- and fourth-order spherical aberrations were exported for 5.0-mm pupils. In this prospective comparative study, 23 healthy subjects underwent bilateral examination with four aberrometers: the Irx3 (Hartmann-Shack Imagine Eyes, Orsay, France), Keratron (Hartmann-Shack Optikon, Rome Italy), iTrace (ray-tracing Tracey Technologies, Houston, TX), and OPD-Scan (Automated Retinoscopy Nidek, Gamagori, Japan). To compare total ocular aberrations and corneal aberrations identified with four different aberrometers and to determine the repeatability and interobserver variability.
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