Suchergebnisse

15 pags., 10 figs. 3 tabs. ; We present a new metric (Multifocal Acceptance Score, MAS-2EV) to evaluate vision with presbyopic corrections. The MAS-2EV is based on a set of images representing natural visual scenes at day and night conditions projected in far and near displays, and a near stereo target. Subjects view and score the images through diferent binocular corrections (monofocal corrections at far; bifocal corrections; monovision and modifed monovision) administered with soft contact lenses (in cyclopleged young subjects) or with a binocular simultaneous vision simulator (in presbyopic and cyclopleged young subjects). MAS-2EV scores are visually represented in the form of polygons, and quantifed using diferent metrics: overall visual quality, visual degradation at far, visual beneft at near, near stereo beneft, visual imbalance near-far, overall visual imbalance and a combined overall performance metric. We have found that the MAS-2EV has sufcient repeatability and sensitivity to allow diferentiation across corrections with only two repetitions, and the duration of the psychophysical task (3 min for subject/condition/correction) makes it useable in the clinic. We found that in most subjects binocular bifocal corrections produce the lowest visual imbalance, and the highest near stereo beneft. 46.67% of the subjects ranked binocular bifocal corrections frst, and 46.67% of the subjects ranked monovision frst. MAS-2EV, particularly in combination with visual simulators, can be applied to select prospective presbyopic corrections in patients prior to contact lens ftting or intraocular lens implantation. ; European Research Council (ERC-2011-AdC 294099 to SM); Spanish Government (FIS2017-84753R to SM, ISCIII DTS16/00127 to CD, DI-15-07753 to JLM, PTQ-15-07432 to EG, PTA2017-13787-I to MR), and Madrid Regional Government (IND2017/BMD-7670 to XB). ; Peer reviewed

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

Esta investigación aborda la significación de la maternidad en mujeres que viven con VIH. Se parte del supuesto del VIH como enfermedad estigmatizada y como punto de quiebre en la trayectoria de vida. Se entrevistaron a ocho mujeres en diferente situación de maternidad que acudían a los Servicios de Atención Integral del Hospital de Las Culturas, en San Cristóbal de Las Casas, Chiapas. Los resultados indican tensiones y contradicciones respecto de la maternidad con la presencia del VIH. El riesgo de transmisión, la posibilidad del daño y la sensación de haber fallado como madres son elementos que forman parte de la experiencia y conforman una idea de incompatibilidad entre ser madre y vivir con VIH.

16 pags. 6 figs., 1 tab. ; Purpose: As multifocal contact lenses (MCLs) expand as a solution for presbyopia correction, a better understanding of their optical and visual performance becomes essential. Also, providing subjects with the experience of multifocal vision before contact lens fitting becomes critical, both to systematically test different multifocal designs and to optimize selection in the clinic. In this study, we evaluated the ability of a simultaneous vision visual simulator (SimVis) to represent MCLs. Methods: Through focus (TF) optical and visual quality with a center-near aspheric MCL (low, medium and high near adds) were measured using a multichannel polychromatic Adaptive Optics visual simulator equipped with double-pass, SimVis (temporal multi-plexing), and psychophysical channels to allow measurements on-bench and in vivo. On bench TF optical quality of SimVis-simulated MCLs was obtained from double-pass (DP) images and images of an E-stimulus using artificial eyes. Ten presbyopic subjects were fitted with the MCL. Visual acuity (VA) and DP retinal images were measured TF in a 4.00 D range with the MCL on eye, and through SimVis simulations of the same MCLs on the same subjects. Results: TF optical (on bench and in vivo) and visual (in vivo) quality measurements captured the expected broadening of the curves with increasing add. Root mean square difference between real and SimVis-simulated lens was 0.031/0.025 (low add), 0.025/0.015 (medium add), 0.019/0.011 (high add), for TF DP and TF LogMAR VA, respectively. A shape similarity metric shows high statistical values (lag κ = 0), rho = 0.811/0.895 (low add), 0.792/0.944 (medium add), and 0.861/0.915 (high add) for TF DP/LogMAR VA, respectively. Conclusions: MCLs theoretically and effectively expand the depth of focus. A novel simulator, SimVis, captured the through-focus optical and visual performance of the MCL in most of the subjects. Visual simulators allow subjects to experience vision with multifocal lenses prior to testing them on-eye. Translational Relevance: Simultaneous visual simulators allow subjects to experience multifocal vision non-invasively. We demonstrated equivalency between real multifocal contact lenses and SimVis-simulated lenses. The results suggest that SimVis is a suitable technique to aid selection of presbyopic corrections in the contactology practice. ; Supported by the European Research Council (ERC-2011-AdC 294099) to SM; Spanish Government (FIS2017-84753R) to SM, and pre-doctoral fellowship (FPU16/01944) to SA; Collaborative agreement with Johnson & Johnson Vision, Inc., Research & Development, Jacksonville, FL, USA.

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

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019 ; Support European Research Council ERC-2011-AdG-294099; Spanish Government: FIS2017-84753-R, PTQ-15-07432, and ISCIII DTS16/00127; Spanish Goverment predoctoral program FPU16/01944; Collaborative agreement with Johnson & Johnson Vision, Inc., Jacksonville, FL, USA ; Peer reviewed