Suchergebnisse

21 pags., 9 figs., 1 tab. ; A better understanding of visual performance with Multifocal Contact Lenses (MCLs) is essential, both in young eyes, where MCLs may be prescribed to control the progression of myopia wherein the MCLs optics interact with accommodation, and in presbyopes, where MCLs are increasingly used to compensate the lack of accommodation. In this study, we evaluated the through focus visual acuity (TFVA) with center-near MCLs of three additions (low, medium and high) and without an addition (NoLens) in 10 young adults and 5 presbyopes. We studied the effect of accommodation, age and pupil diameter (in cyclopleged subjects) on visual performance. The MCLs produced a small but consistent degradation at far (by 0.925 logMAR, averaged across eyes and conditions) and a consistent benefit at near in young subjects with paralyzed accommodation (by 1.025 logMAR), and in presbyopes with both paralyzed and natural accommodation (by 1.071 logMAR, on average). TFVA in young adults with NoLens and all MCLs showed statistically significant differences (Wilcoxan, p<0.01) between natural and paralyzed accommodation, but not in presbyopes with MCLs. In young adults, VA improved with increasing pupil diameter with the HighAdd MCL (0.08 logMAR shift from 3 to 5-mm pupil size). Visual imbalance (standard deviation of VA across distances) was reduced with MCLs, and decreased significantly with increasing near add. The lowest imbalance occurred in young adults under natural accommodation and was further reduced by 13.33% with MCLs with respect to the NoLens condition. Overall, the visual performance with MCLs in young adults exceeds that in presbyopes at all distances, and was better than 0.00 logMAR over the dioptric range tested. In conclusion, the center-near lenses do not degrade the near high contrast visual acuity significantly but maintains the far vision in young adults, and produce some visual benefit at near in presbyopes. ; This research has received funding from the European Union's Horizon 2020 ...

17 pags., 9 figs. ; We have measured the ocular transverse chromatic aberration (TCA) in 11 subjects using 2D-two-color Vernier alignment, for two pupil diameters, in a polychromatic adaptive optics (AO) system. TCA measurements were performed for two pupil diameters: for a small pupil (2-mm), referred to as 'optical TCA' (oTCA), and for a large pupil (6-mm), referred to 'perceived TCA' (pTCA). Also, the TCA was measured through both natural aberrations (HOAs) and AO-corrected aberrations. Computer simulations of pTCA incorporated longitudinal chromatic aberration (LCA), the patient's HOAs measured with Hartmann-Shack, and the Stiles-Crawford effect (SCE), measured objectively by laser ray tracing. The oTCA and the simulated pTCA (no aberrations) were shifted nasally 1.20 arcmin and 1.40 arcmin respectively. The experimental pTCA (-0.27 arcmin horizontally and -0.62 vertically) was well predicted (81%) by simulations when both the individual HOAs and SCE were considered. Both HOAs and SCE interact with oTCA, reducing it in magnitude and changing its orientation. The results indicate that estimations of polychromatic image quality should incorporate patient's specific data of HOAs, LCA, TCA & SCE. ; European Research Council (ERC-2011-AdC 294099); H2020 Marie Skłodowska-Curie Actions (H2020 COFUND Marie Curie 291820 program); Spanish Government (FIS2014-56643R, FIS2017-84753R, FPU16/01944, ISCIII DTS16/00127).

ARVO Annual Meeting Abstract (2019) ; Support Spanish Government Grant FIS2014-56643-R Spanish Government Grant FIS2017-84753-R European Project Presbyopia ERC-2011-AdG Ref. 294099 Spanish Government Predoctoral Grant FPU16/01944 ; Peer reviewed

14 pags., 5 figs. ; Convolved images are often used to simulate the effect of ocular aberrations on image quality, where the retinal image is simulated by convolving the stimulus with the point spread function derived from the subject's aberrations. However, some studies have shown that convolved images are perceived far more degraded than the same image blurred with optical defocus. We hypothesized that the positive interactions between the monochromatic and chromatic aberrations in the eye are lost in the convolution process. To test this hypothesis, we evaluated optical and visual quality with natural optics and with convolved images (on-bench, computer simulations, and visual acuity [VA] in subjects) using a polychromatic adaptive optics system with monochromatic (555 nm) and polychromatic light (WL) illumination. The subject's aberrations were measured using a Hartmann Shack system and were used to convolve the visual stimuli, using Fourier optics. The convolved images were seen through corrected optics. VA with convolved stimuli was lower than VA through natural aberrations, particularly in WL (by 26% in WL). Our results suggest that the systematic decrease in visual performance with visual acuity and retinal image quality by simulation with convolved stimuli appears to be primarily associated with a lack of favorable interaction between chromatic and monochromatic aberrations in the eye. ; Supported by the Spanish Government (FIS2017-84753R, PID2020-115191RB-I00) to SM; Spanish Government Predoctoral (Grant FPU16/01944) to SA; H2020 Marie Sklodowska-Curie Actions (H2020 MSCA IF GF 2019 MYOMICRO 893557) to MV; European Research Council (ERC-2018-ADG SILKEYE 833106), NIH NIE P30EY 001319; and Unrestricted Funds Research to Prevent Blindness to SM. ; Peer reviewed

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018 ; Support European Research Council ERC-2011-AdG-294099; Spanish Government FIS2014 ; Peer reviewed

ARVO Annual Meeting Abstract , June 2020 ; Spanish government grant FIS2017-84753-R, European Project PRESBYOPIA ERC-2011-AdG Ref. 294099, European Project MyFUN H2020MSCA-ITN-2015 Ref. 675137 ; Peer reviewed

ARVO Annual Meeting Abstract (2019) ; Support a collaborative agreement with Essilor International, France. Spanish government grant FIS2014-56643-R, Spanish government grant FIS2017-84753-R, European Research Council under the European Union's Seventh Framework Programme (FP7/2007-2013) ERC-2011-AdG-294099 ; Peer reviewed

11 pags., 7 figs. -- Open Access funded by Creative Commons Atribution Licence 4.0 ; Adaptive optics (AO) visual simulators based on deformable mirrors, spatial light modulators or optotunable lenses are increasingly used to simulate vision through different multifocal lens designs. However, the correspondence of this simulation with that obtained through real intraocular lenses (IOLs) tested on the same eyes has not been, to our knowledge, demonstrated. We compare through-focus (TF) optical and visual quality produced by real multifocal IOLs (M-IOLs) -bifocal refractive and trifocal diffractive- projected on the subiect's eye with those same designs simulated with a spatial light modulator (SLM) or an optotunable lens working in temporal multiplexing mode (SimVis technology). Measurements were performed on 7 cyclopleged subjects using a custom-made multichannel 3-active-optical-elements polychromatic AO Visual Simulator in monochromatic light. The same system was used to demonstrate performance of the real IOLs, SLM and SimVis technology simulations on bench using double-pass imaging on an artificial eye. Results show a general good correspondence between the TF performance with the real and simulated M-IOLs, both optically (on bench) and visually (measured visual acuity in patients). We demonstrate that visual simulations in an AO environment capture to a large extent the individual optical and visual performance obtained with real M-IOLs, both in absolute values and in the shape of through-focus curves. ; Tis research has received funding from the European Research Council under the European Union's Seventh Framework Program (FP/2007–2013)/ERC Grant Agreement. [ERC-2011-AdC 294099]; the H2020 COFUND Marie Curie 291820 program; ERCPoC SimVis project. Tis study was also supported by Spanish Government grant FIS2014-56643-R to S.M., FIS2017-84753-R to S.M. and C.D., and DTS16-00127 to C.D., and Spanish Government FPU Predoctoral Fellowship (FPU16/01944) to S.A. Authors thank Laura Barrios from the Scientifc Calculus Center of the Spanish National Research Council (CSIC) for help with the statistical analysis.

15 pags., 9 figs., 1 tab. ; Visual simulators aim at evaluating vision with ophthalmic corrections prior to prescription or implantation of intraocular lenses (IOLs) in the patient's eye. In the present study, we present the design, implementation, and validation of a new IOL-in-cuvette channel in an Adaptive Optics visual simulator, which provides an alternative channel for pre-operative simulation of vision with IOLs. The IOL is projected on the pupil's plane of the subject by using a Rassow system. A second lens, the Rassow lens, compensates for an IOL of 20 D while other powers can be corrected with a Badal system within a 5 D range. The new channel was evaluated by through-focus (TF) optical quality in an artificial eye on bench, and by TF visual acuity in patients, with various IOL designs (monofocal, diffractive trifocal, and refractive extended depth of focus). ; Funding. Spanish Government (FIS2017-84753R) ; Peer reviewed

16 pags., 9 figs., 1 tab. -- Open Access funded by Creative Commons Atribution Licence 4.0 ; Tunable lenses are becoming ubiquitous, in applications including microscopy, optical coherence tomography, computer vision, quality control, and presbyopic corrections. Many applications require an accurate control of the optical power of the lens in response to a time-dependent input waveform. We present a fast focimeter (3.8 KHz) to characterize the dynamic response of tunable lenses, which was demonstrated on different lens models. We found that the temporal response is repetitive and linear, which allowed the development of a robust compensation strategy based on the optimization of the input wave, using a linear time-invariant model. To our knowledge, this work presents the first procedure for a direct characterization of the transient response of tunable lenses and for compensation of their temporal distortions, and broadens the potential of tunable lenses also in high-speed applications. ; VA and EL acknowledge financial support from Comunidad de Madrid and Marie Curie Action of the European Union FP7/2007-2013 COFUND 291820; XB from Comunidad de Madrid Doctorado Industrial IND2017/BMD-7670; EL from Spanish Government Ramon y Cajal Program RyC-2016-21125; EG from Spanish Government Torres-Quevedo Program PTQ-15-07432; LS from EU H2020 SME Innovation Associate GA-739882; EG from EIT Health; SM from ERC Grant Agreement ERC-2011-AdC 294099 and Spanish Government Grants FIS2014-56643-R; SM and CD from Spanish Government Grant FIS2017-84753-R; and CD from DTS16-00127.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018. ; Support European Research Council ERC-2011-AdG-294099; Spanish Government: FIS2014-56643-R, PTQ-15-07432, and ISCIII DTS16/00127; Collaborative agreement with Physiol (Liege, Belgium) ; Peer reviewed