binocular vision dysfunction

INTRODUCTION: Reading is a vision-reliant task, requiring sequential eye movements. Binocularly discordant input results in visual sensory and oculomotor dysfunction in amblyopia, which may contribute to reading difficulties. This study aims to determine the contributions of fixation eye movement (FEM) abnormalities, clinical type and severity of amblyopia to reading performance under binocular and monocular viewing conditions. METHODS: Twenty-three amblyopic patients and nine healthy controls were recruited...

Reading involves adequate coordination of the oculomotor system. As interlink consists of neuronal control, an insult to the brain might affect the signal processing and lead to oculomotor dysfunction that can affect reading performance. Appropriate training to enhance the oculomotor coordination is effective in such scenarios. The purpose of this case report is to highlight the role of neuro-optometric vision therapy as a management option in oculomotor-based reading difficulty.

The aim of our study was to compare computer visual syndrome (CVS) in a tweenager student population who use tablets and laptops only to play versus CVS in tweenagers who use these digital devices at school to study, in addition to playing. The tests performed were a validated survey for children for the detection of CVS and accommodative and vergence tests. The CVS item questionnaire was divided into four main groups based on questions concerning the following: (I) the digital device usage time, (II) musculoskeletal and ergonomic nature, (III) visual symptoms, and (IV) ocular surface symptoms...

OBJECTIVE: To identify normative near point of convergence (NPC) data for healthy high-school-aged athletes (13-19 years old) and determine the percentage of individuals with NPC scores that fall outside the currently accepted clinical cutoff value of 5 cm. Another objective was to determine the relationship between sex, concussion history, and attention deficit disorder/attention deficit hyperactivity disorder (ADD/ADHD) with NPC scores, if any. DESIGN: Case series...

Purpose: To compare the short-term treatment effect of low plus reading addition (ADD) and home-based vision therapy (VT) in a small group of symptomatic children with accommodative infacility (AIF) being the most significant dysfunction. Methods: Nineteen children, 8 to 12 years of age, with a first-time diagnosis of AIF were consecutively and alternately allocated to treatment with ADD (+0.50 D addition in single vision Rx) or VT (accommodation exercises using Hart Charts) for a period of 6 weeks...

Purpose: The transition of Taiwan from an aging to a super-aging society has come with a cost as more elderly now suffer from cognitive impairment. The main purpose of our study was to investigate if early detection can be developed so that timely intervention can be instituted. We analyzed the correlation of cognitive function with ocular physiology and visual functions between senior citizens aged 60 years or older in Taiwan. Methods: Thirty-six healthy subjects were recruited for the study. Addenbrooke's cognitive examination III (ACE-III), binocular functions (including objective and subjective refraction, distance and near dissociated phoria, stereopsis, contrast sensitivity, adult developmental eye movement (ADEM), and ocular physiology (by using optical coherence tomography, OCT, and macular pigment measurement, MPS) were performed, and the data were analyzed via independent t -test, chi-square test, Pearson correlation, linear regression, and ROC (receiver operating characteristic) curve...

Background: Alstrom syndrome (ALMS) is an ultra-rare multisystem genetic disorder caused by autosomal recessive inheritance of the ALMS1 gene. It manifests as multisystem dysfunction, displaying unique clinical signs and symptoms and various severity, which may lead to delayed prognosis or misdiagnosis in medical practice. Although almost 300 pathogenic variants have been reported, there are some variant sites that have not been recognized yet. Case Description: We report a case of a 14-year-old boy with manifestations, including binocular vision loss, acanthosis nigricans, type 2 diabetes, insulin resistance, elevated transaminase, hepatic fibrosis, and proteinuria...

BACKGROUND: This study is the first part of the "Binocular Vision Anomalies after Cataract Surgery" study that aimed to investigate the impact of cataract surgery on binocular vision status in adults with age-related cataract. This study aimed to investigate the preoperative binocular vision status of participants with age-related cataract. METHODS: Patients who elected to undergo bilateral cataract surgery (≥50 years of age) were recruited. Clinical measures of binocular vision including stereopsis, ocular alignment, fusional vergence, vergence facility, convergence amplitude and a symptom survey related to binocular vision anomalies were administered...

BACKGROUND: Virtual reality is being increasingly applied in vision therapy. However, the differences in effectiveness, optimal treatment cycle, and prognosis between virtual reality-based vision therapy and traditional therapies remain unknown. The purpose of this study was to compare the effectiveness of virtual reality-based vision therapy and office-based vergence/accommodative therapy in young adults with convergence insufficiency or accommodative dysfunction. METHODS: The patients were randomly assigned to either the virtual reality-based vision therapy group or the office-based vergence/accommodative therapy group...

45.1% of AMD patients perceive visual distortion or metamorphopsia in at least one of their eyes. These distortions pose severe impediment to reading, face recognition and visual search. Adaptation to these dysfunctions are generally preceded by development of significant visual loss. In this study we investigate how different levels of suppression accelerate this adaptation by simulating central, paracentral and cecocentral metamorphopsia monocularly, and then suppressing the resulting perception by overlaying a scotoma (completely black circle)...

Purpose: To assess psychometric properties of the Symptom Questionnaire for Visual Dysfunctions (SQVD) questionnaire, including accuracy, validity, and reliability, in a clinical sample of patients having any type of visual dysfunction. Methods: A clinical sample of 306 patients self-administered the SQVD. Rasch analysis was performed to analyze the functionality of the response categories, fit statistics, differential item functioning (DIF), person and item reliability, targeting, local dependency, unidimensionality, and transformation table...

The numerous multistable phenomena in vision, hearing and touch attest that the inner workings of perception are prone to instability. We investigated a visual example-binocular rivalry-with an accurate no-report paradigm, and uncovered developmental and maturational lifespan trajectories that were specific for age and sex. To interpret these trajectories, we hypothesized that conflicting objectives of visual perception-such as stability of appearance, sensitivity to visual detail, and exploration of fundamental alternatives-change in relative importance over the lifespan...

BACKGROUND: Myopathies are neuromuscular disorders of the skeletal muscles, in which the main symptom is muscle weakness due to muscle fiber dysfunction. Myopathies may be classified into two main categories: inherited and acquired. Hereditary myopathies are a heterogeneous group of diseases that include congenital myopathies, mitochondrial myopathies, myotonic syndromes, muscular dystrophies, and other myopathies. PURPOSE: The objective of this paper is to review the ophthalmological findings and genetic patterns of hereditary myopathies...

OBJECTIVE: To explore the utility of an eye-tracking assessment in distinguishing binocular alignment, saccadic movement, and pupillary dynamics among uninjured adolescents, acute cases (= 28 days since concussion), and persistent cases (>28 days since concussion). BACKGROUND: Visual and autonomic system disturbances are common sequelae of concussion. Quantification of visual and autonomic dysfunction via an eye tracking device could provide an objective method of acute diagnosis and subacute identification of ongoing injury...

SIGNIFICANCE: This is the first report recording an accommodative disorder after concussion characterized by periodic moderately sized myopic refractive error fluctuations without measurable other features of spasm of the near reflex. PURPOSE: Objectively document a class of accommodative dysfunction that may be related to concussion. CASE REPORTS: Case 1 involved two sports-related concussions 2 months apart with symptoms of headache and variable blur...

CLINICAL RELEVANCE: The extent of binocular vision dysfunction in elite soccer players needs to be determined as it may impact performance. BACKGROUND: The purpose of the study was to investigate the prevalence of binocular vision dysfunctions in elite soccer players. METHODS: One hundred and seven professional soccer players were evaluated. Refractive error was measured and the following binocular vision parameters were assessed: horizontal and vertical phoria for distance and near vision, the values of break and recovery for negative and positive fusional vergences at distance and near vision, vergence facility at distance and near vision, monocular accommodative facility at near vision, and near point of convergence (break and recovery points)...

BACKGROUND: Several studies have suggested that accommodative and non-strabismic binocular dysfunctions are commonly encountered in optometric practice. This study aims to verify whether these findings apply to a Portuguese clinical population. METHODS: This study included consecutive nonpresbyopic subjects that came to two Portuguese optometric clinics over a period of six months. A complete visual exam was conducted and included the measurement of visual acuity (VA), refraction, near point of convergence (NPC), distance and near phoria, near and distance fusional vergences, amplitude of accommodation (AA), monocular accommodative facility (MAF), relative accommodation and lag of accommodation...

OBJECTIVE: To evaluate benefits of binocular vision and ocular motility training in patients with long-term sequelae after mild traumatic brain injury (mTBI). METHODS: Twenty-eight mTBI (concussion) patients from 25 to 61 years of age with oculomotor dysfunction were selected by optometric examination. The vision therapy was designed to improve convergence, pursuit and saccades as well as to increase fusional reserves. The vision therapy was conducted by a neurooptometrist and a speech therapist, and took place weekly for 1 hour during 10 continuous weeks...

SIGNIFICANCE: Ocular light exposure therapy has been used in optometric therapies to improve binocular anomalies such as accommodative or vergence dysfunctions, amblyopia therapy or to increase the visual field. Currently, syntonic phototherapy is used worldwide by behavioral optometrists, vision trainers or occupational therapists, among others, although these treatments are supported by only a few research studies which lack consensus on the efficacy of this approach. PURPOSE: In this paper, we highlight the optical characteristics of lamps without evaluating the efficacy of their use in optometric procedures...

Purpose: To determine the prevalence of fusional vergence dysfunction (FVD) and its relationship with age, sex, and refractive errors in a population-based study. Methods: In this cross-sectional study, all residents of Mashhad, northeast of Iran, aged >1 year were subjected to random stratified cluster sampling. After selecting the participants, they all underwent complete optometric examinations including the measurement of visual acuity and refraction, assessment of binocular vision and accommodative status, and slit-lamp biomicroscopy...