Optimal Optotype Structure for Monitoring Visual Acuity

Abstract

Communicated by Ivars Lâcis

Visual results and subjective satisfaction after implantation of two different trifocal diffractive intraocular lenses models (AcrySof IQ PanOptix and AT LISA tri 839 MP)

“…Letter optotypes are also essential in these charts, reducing the study's reliability. [20][21][22] The screens of computer monitors and smartphones have respective pixel sizes and brightness required for reliable visual acuity test. Thus, using ICP should provide accurate enough VA measurement at any distance.…”

“…These stimuli' stripes' length is extended by approximately 20% compared with the standard triple optotype to ensure the indistinguishability of near-edge stimuli by indirect signs of blurred spot orientation. [20][21][22] The VA test using a computer program was performed using "E" optotype oriented in 4 ways. Intermediate VA was assessed at 60 cm away from the subject's eye after PanOptix implantation and 80 cm away from the eye after AT LISA tri implantation.…”

“…Russian researchers from the Institute for Information Transmission Problems (Kharkevich Institute) of the Russian Academy of Sciences have developed an interactive computer program (ICP) using two kinds of optotypes: modified triple stimuli oriented in two ways and "E" sign oriented in four different ways, so-called "tumbling E". [19][20][21] We initially used this visual test tool to analyze the implantation performance of trifocal IOL model. 22 This study aimed to compare visual outcomes after implantation of the two models of trifocal diffractive IOL using decimal scale and LogMAR scales, ICP, and contrast functional vision test systems.…”

Trends in the development of Medicine, Biology and Pharmacy

“…Some studies demonstrated that meridional amblyopia in children can be found associated with hyperopic astigmatism [94][95][96], whereas others reported that children with hyperopic astigmatism showed no meridional amblyopia, but did show reduced acuity for both grating orientations [89,97]. These contradictions have been attributed to the fact that the studies vary in methodologies and criteria used for visual acuity assessment [91,98,99]. These factors cause differences not only in meridional visual acuity, but also in results of any other visual acuity measurement methods [99,100].…”

“…These selective criteria include such visual perception threshold characteristics as minimum perceptible, minimum visible, mini¬mum resolvable, minimum separable, minimum discrim¬inable, minimum deformable, etc. It should be noted that these criteria are fundamentally different from each other and characterize the state of various visual acuity mechanisms[98,99, 101,104,105]. Thus, minimum visible characterizes the ability to note the presence of an object; minimum perceptible characterizes the ability to note the presence a threshold contrast; minimum separable or minimum resolvable acuity characterizes the ability to distinguish among the details of the object structure; and minimum perceptible allows assessing the shape of a pattern through its contour.…”