Retinal Responses to Simulated Optical Blur Using a Novel Dead Leaves ERG Stimulus.

Purpose: The purpose of this study was to evaluate retinal responses to different types and magnitudes of simulated optical blur presented at specific retinal eccentricities using naturalistic images.

Methods: Electroretinograms (ERGs) were recorded from 27 adults using 30-degree dead leaves naturalistic images, digitally blurred with one of three types of optical blur (defocus, astigmatism, and spherical aberrations), and one of three magnitudes (0.1, 0.

A Comparison Between Refraction From an Adaptive Optics Visual Simulator and Clinical Refractions.

Purpose: The Visual Adaptive Optics (VAO) is an adaptive optics visual simulator with an embedded Hartmann-Shack aberrometer that can give objective and subjective refraction measures. The aim of the present study was to compare the findings of the objective and subjective refractions from the VAO with a commercial autorefractometer (Topcon Corp., Tokyo, Japan) and a subjective refraction by an optometrist.

Author Correction: Comparison of different smartphone cameras to evaluate conjunctival hyperaemia in normal subjects.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Stimulus Unpredictability in Time, Magnitude, and Direction on Accommodation.

Significance: The effect of predictability in changes of time, magnitude, and direction of the accommodation demand on the accommodation response latency and its magnitude are insignificant, which suggests that repetitive accommodative tasks such as the clinical accommodative facility test may not be influenced by potential anticipation effects.

Purpose: The purpose of this study was to investigate the effect of stimulus' time, magnitude, and direction predictability, as well as their interactions, on accommodation latency and response magnitude.

Methods: Monocular accommodative response and latency were measured in 12 young subjects for nine different conditions where the stimulus accommodative demand changed several times in a steplike fashion for a period of 120 seconds.

Comparison of different smartphone cameras to evaluate conjunctival hyperaemia in normal subjects.

Despite the significant advantages that smartphones' cameras can provide in teleophthalmology and artificial intelligence applications, their use as black-box systems for clinical data acquisition, without adequate information of the quality of photographs can compromise data accuracy. The aim of this study is to compare the objective and subjective quantification of conjunctival redness in images obtained with calibrated and non-calibrated cameras, in different lighting conditions and optical magnifications. One hundred ninety-two pictures of the eye were taken in 4 subjects using 3 smartphone cameras{Bq, Iphone, Nexus}, 2 lighting levels{high 815 lx, low 122 lx} and 2 magnification levels{high 10x, low 6x}.

Clinical evaluation of an automated subjective refraction method implemented in a computer-controlled motorized phoropter.

Purpose: To investigate a new algorithm to perform an automated non-cycloplegic refraction in adults.

Methods: Fifty healthy subjects were measured twice (test-retest) with the new automated subjective refraction method and with the conventional clinician subjective refraction procedure. Objective refraction was also measured with the Grand Seiko WAM-5500 autorefractor.

An automated and objective cover test to measure heterophoria.

Heterophoria is the relative deviation of the eyes in absence of fusional vergence. Fusional vergence can be deprived by, for example, occluding one eye while the other fixates a visual target. Then, the occluded eye will presumably deviate from its initial position by an amount that corresponds to the heterophoria.

Random Changes of Accommodation Stimuli: An Automated Extension of the Flippers Accommodative Facility Test.

Purpose: To study the accommodative dynamics for predictable and unpredictable stimuli using manual and automated accommodative facility tests Materials and Methods: Seventeen young healthy subjects were tested monocularly in two consecutive sessions, using five different conditions. Two conditions replicated the conventional monocular accommodative facility tests for far and near distances, performed with manually held flippers. The other three conditions were automated and conducted using an electro-optical system and open-field autorefractor.

Effect of Experimental Conditions in the Accommodation Response in Myopia.

Significance: The accommodative response is more affected by the type of refractive error than the method of stimulation, field of view (FOV), or stimulus depth.

Purpose: This study aims to analyze the effect of stimulation method, stimulus depth, and FOV on the accommodation response (AR) for emmetropes (EMM), late-onset myopes (LOM), and early-onset myopes (EOM).

Methods: Monocular AR was measured in 26 young observers (n = 9 EMM, n = 8 LOM, n = 9 EOM) under 60 different viewing conditions that were the result of permuting the following factors: (1) stimulation method (free space or Badal lens viewing), (2) stimulus depth (flat or volumetric), (3) FOV (2.

Suitability of open-field autorefractors as pupillometers and instrument design effects.

Aim: To determine the agreement and repeatability of the pupil measurement obtained with VIP-200 (Neuroptics), PowerRef II (Plusoptix), WAM-5500 (Grand Seiko) and study the effects of instrument design on pupillometry.

Methods: Forty patients were measured twice in low, mid and high mesopic. Repeatability was analyzed with the within-subject standard deviation (Sw) and paired -tests.

Effect of apparent depth cues on accommodation in a Badal optometer.

Background: The aim was to analyse the effect of peripheral depth cues on accommodation in Badal optometers.

Methods: Monocular refractions at 0.17 and 5.

Does the Badal optometer stimulate accommodation accurately?

Purpose: To study whether the accommodation response to Badal optometer is equivalent to the response for real space targets.

Methods: Accommodative responses were measured for 28 young eyes with the WAM-5500 autorefractometer in eight configurations for 0.17 D, 2.

Comparison of the Adaptive Optics Vision Analyzer and the KR-1 W for measuring ocular wave aberrations.

Background: The aim was to assess the agreement in the measurement of ocular aberrations between a new Adaptive Optics Vision Analyzer (AOVA, Voptica, Murcia, Spain) and a commercial aberrometer (KR-1 W, Topcon, Tokyo, Japan), both based on the Hartmann-Shack technique.

Methods: One experienced examiner measured 29 healthy right eyes nine consecutive times with the two instruments. The individual Zernike coefficients and the root mean square (RMS) of each order from the second to the fifth order, the higher-order RMS (RMS ), the total RMS (RMS ) and the values of the spherical equivalent (M) and Jackson cross-cylinder (J and J ) were compared.

Spherical subjective refraction with a novel 3D virtual reality based system.

Purpose: To conduct a clinical validation of a virtual reality-based experimental system that is able to assess the spherical subjective refraction simplifying the methodology of ocular refraction.

Methods: For the agreement assessment, spherical refraction measurements were obtained from 104 eyes of 52 subjects using three different methods: subjectively with the experimental prototype (Subj.E) and the classical subjective refraction (Subj.

Repeatability of aberrometric measurements with a new instrument for vision analysis based on adaptive optics.

Purpose: To evaluate intersession and intrasession repeatability of aberration data obtained with a new visual simulator based on adaptive optics, which includes a Hartmann-Shack aberrometer (Adaptive Optics Vision Analyzer; Voptica S.L., Murcia, Spain).