Aberrometry: clinical and research applications.

O ptometry has a history of taking the lead in correcting the optical defects of the eye. While the primary definition of optometry has changed as the profession has expanded its scope of practice, the secondary definition of optometry has remained unchanged. The second definition of optometry is the use of an optometer. The definition of optometer is any of several objective or subjective devices for measuring the refractive state of the eye. There is no better way of measuring the refractive state of the eye than to measure its wavefront error using state-of-the-art aberrom-eters. State-of-the-art aberrometry opens doors for new research and clinical applications while creating a new set of issues and opportunities. We will briefly discuss a few in this editorial. State-of-the-art aberrometry provides detailed analysis of the optical performance of refractive corrections. That is, it provides a sensitive tool for measuring how optical aberrations of the correcting devices combine with the subject's own aberrations. For example: What are the sources of optical aberrations in progressive spectacles, and soft and rigid contact lenses? What amount of optical degradation is induced or reduced by different types of corneal and intraocular surgeries? The answer to these questions provided by aberrometry will lead to an optimization of a variety of correcting devices and procedures and to a better customization of the individual correction. Aberrometry is rapidly making its way into the clinic, yet there are many technical issues still being carefully looked at in the laboratory. While the Hartmann-Shack aberrometer has been the most widely adopted, other approaches are being used both in the laboratory and in commercially available instruments. Are all aberrometers equivalent? Are there particular types of aberrometers that are more appropriate for a particular application? What is the ideal pupil sampling config-uration? Are measurements affected by defocus or by wavelength? Aberrometry measures the contribution of only one source of degradation (aberrations). How do we incorporate the effects of scattering into the optical quality, and what is the best method to measure its contribution? Aberrometry itself is not a closed technology. New research and new technology will continue to contribute to a better understanding of the measurement and a more complete set of tools. State-of-the-art aberrometry provides necessary data for designing ideal corrections for the eye. Receiving less attention is the fact that the same aberroscopic data allow for a noninvasive microscopic view into the living eye. Said differently, …