Original articleLaser In Situ Keratomileusis Disrupts the Aberration Compensation Mechanism of the Human Eye
Section snippets
Subjects
Ocular, corneal, and internal aberrations were measured before and 6 months after standard LASIK. Surgical procedures were performed using a VISX S2 (AMO, Santa Ana, California, USA) excimer laser platform at “Clinica Ircovisión” (Cartagena, Murcia, Spain). The measured population included 21 eyes (n = 11 subjects) classified according to their preoperative refractive error: 1 group including myopic eyes (n = 15 eyes; mean age ± standard deviation [SD], 28.0 ± 3.6 years; mean sphere, −4.08 ±
Results
Figure 2 shows average ocular, corneal, and internal aberrations for a 6-mm pupil for the groups of myopic and hyperopic eyes. Before surgery, hyperopic eyes had more corneal and internal aberrations than myopes, mainly because of a higher coma for each component (cornea and lens). However, the overall ocular aberrations were similar to myopes because of the previously described coupling of corneal and internal SA and coma in young hyperopes. This scenario clearly was modified by the surgery:
Discussion
We estimated the corneal aberrations by considering a simplified cornea with one single surface, the measured corneal anterior surface, and by using an effective refractive index for corneal aberration calculations. By doing so, we did not completely consider the effect of the corneal posterior surface. This is probably a minor issue in normal eyes, but this may not be the case after LASIK. The behavior of the corneal posterior surface after LASIK and it role in the increment of aberrations has
Antonio Benito, after finishing his degree in Optics and Optometry, joined the Pablo Artal's “Laboratorio de Óptica de la Universidad de Murcia”, Murcia, Spain in 1998. He has recently completed an MSc course at the Department of Physics at the Universidad de Murcia, Spain. His research interests have been focused on aberrations of the human eye, especially on ocular aberration compensation mechanism and optical effects of laser in situ keratomileusis on the aberrations of the eye and it
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Antonio Benito, after finishing his degree in Optics and Optometry, joined the Pablo Artal's “Laboratorio de Óptica de la Universidad de Murcia”, Murcia, Spain in 1998. He has recently completed an MSc course at the Department of Physics at the Universidad de Murcia, Spain. His research interests have been focused on aberrations of the human eye, especially on ocular aberration compensation mechanism and optical effects of laser in situ keratomileusis on the aberrations of the eye and it components.