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Ocular optics is normally estimated based on up to 2,600 measurement points within the pupil of the eye, which implies a lateral resolution of approximately 175 µm for a 9 mm pupil diameter. This is because information below this resolution is not thought to be relevant or even possible to obtain with current measurement systems. In this work, we characterize the in vivo ocular optics of the human eye with a lateral resolution of 8.6 µm, which implies roughly 1 million measurement points for a pupil diameter of 9 mm. The results suggest that the normal human eye presents a series of hitherto unknown optical patterns with amplitudes between 200 and 300 nm and is made up of a series of in-phase peaks and valleys. If the results are analysed at only high lateral frequencies, the human eye is also found to contain a whole range of new information. This discovery could have a great impact on the way we understand some fundamental mechanisms of human vision and could be of outstanding utility in certain fields of ophthalmology.

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Patients with DEX implants show maximum efficacy at 3mo which then declined progressively, but is still better than baseline values at the end of follow-up.

The results in this small cases series suggest that using an aspheric-customized ablation profile with a target Q-factor equal to 0 in moderate hyperopic LASIK is statistically compatible with a diminishing induced spherical aberration without altering procedural safety when the WaveLight Allegretto 400-Hz excimer laser platform (Alcon Laboratories, Inc., Fort Worth, TX) is used.

The results suggest that implantation of this nonrotational symmetric IOL should improve visual outcomes if it is oriented to coincide with a customized meridian. A simple, practical method is proposed to find an approximation to the angle that an Mplus IOL should be inserted.

Purpose to evaluate the effects of kappa angle and intraocular orientation on the theoretical performance of asymmetric multifocal intraocular lenses (MIOL). Methods For a total of 21 corneal aberrations, a computational analysis simulated the implantation of a computationally designed MIOL. An image quality parameter (IQ) (visually modulated transfer function metric) was calculated for a 5.0-mm pupil and for three conditions: distance, intermediate, and near vision. The procedure was repeated for each eye after a rotation of the MIOL with respect to the cornea from 0º to 360º in 5º steps. Kappa angles from 0 to 900 microns, in 150 microns steps, combined with two two variants of MIOL centration were tested: in the corneal apex or in the center of the entrance pupil. A p-value ≤ 0.05 was considered significant. Results There were statistically significant differences of the IQ depending of the intraocular orientation of the MIOL. If kappa angle was increased, there was a statistically significant decrease of the IQ. The IQ maintained stable when the optimal intraocular orientation was re-calculated for each kappa angle. In general, the inter-variability of the results between subjects was very high. There were no strong evidences supporting that there exists a preferable centration point. Conclusions Our results suggest that kappa angle theoretically affects significantly the performance of asymmetric MIOL implantation. However, its negative effect can be compensated if a customized intraocular orientation is calculated taking into account the presence of the kappa angle.

Abstract:We propose an alternative solution to improve visual quality by spatially modulating the amplitude of light passing into the eye (related to the eye's transmittance), in contrast to traditional correction of the wavefront phase (related to the local refractive power). Numerical simulations show that masking the aberrated areas at the pupil plane should enhance visual function, especially in highly aberrated eyes. This correction could be implemented in practice using customized contact or intraocular lenses.