title: Impact on stereo-acuity of two presbyopia correction approaches: monovision and small aperture inlay.
abstract: Some of the different currently applied approaches that correct presbyopia may reduce stereovision. In this work, stereo-acuity was measured for two methods: (1) monovision and (2) small aperture inlay in one eye. When performing the experiment, a prototype of a binocular adaptive optics vision analyzer was employed. The system allowed simultaneous measurement and manipulation of the optics in both eyes of a subject. The apparatus incorporated two programmable spatial light modulators: one phase-only device using liquid crystal on silicon technology for wavefront manipulation and one intensity modulator for controlling the exit pupils. The prototype was also equipped with a stimulus generator for creating retinal disparity based on two micro-displays. The three-needle test was programmed for characterizing stereo-acuity. Subjects underwent a two-alternative forced-choice test. The following cases were tested for the stimulus placed at distance: (a) natural vision; (b) 1.5 D monovision; (c) 0.75 D monovision; (d) natural vision and small pupil; (e) 0.75 D monovision and small pupil. In all cases the standard pupil diameter was 4 mm and the small pupil diameter was 1.6 mm. The use of a small aperture significantly reduced the negative impact of monovision on stereopsis. The results of the experiment suggest that combining micro-monovision with a small aperture, which is currently being implemented as a corneal inlay, can yield values of stereoacuity close to those attained under normal binocular vision.
authors.affiliation: Laboratorio de Óptica, Instituto Universitario de investigación en Óptica y Nanofísica, Universidad de Murcia, Campus de Espinardo (Edificio 34), E-30100 Murcia, Spain.
authors.forename: Enrique J
authors.initials: EJ
authors.lastname: Fernández
authors.forename: Christina
authors.initials: C
authors.lastname: Schwarz
authors.forename: Pedro M
authors.initials: PM
authors.lastname: Prieto
authors.forename: Silvestre
authors.initials: S
authors.lastname: Manzanera
authors.forename: Pablo
authors.initials: P
authors.lastname: Artal
keywords: (010.1080) Active or adaptive optics; (330.1400) Vision - binocular and stereopsis