scholarly journals A review of the classification of nonstrabismic binocular vision anomalies

2016 ◽  
Vol 5 (1) ◽  
Author(s):  
Charles Darko-Takyi ◽  
Naimah Ebrahim Khan ◽  
Urvashni Nirghin
Keyword(s):  
Binocular Vision ◽  
Systemic Disease ◽  
Clinical Signs ◽  
Review Literature ◽  
Test Procedures ◽  
Convergence Insufficiency ◽  
Different Types ◽  
Proper Diagnosis ◽  
Divergence Insufficiency

There are conflicting and confusing ideas in literature on the different types of accommodative and vergence anomalies as different authors turn to classify them differently. This paper sought to review literature on the different classifications and types of nonstrabismic binocular vision anomalies and harmonize these classifications. Search engines, namely Google scholar, Medline, Cinahl and Francis databases, were used to review literature on the classification of accommodative and vergence dysfunctions using keywords like <em>binocular vision dysfunctions</em>, <em>classification of nonstrabismic binocular vision disorders or anomalies</em>, <em>accommodative disorders/anomalies classification</em> and <em>vergence disorders/anomalies classifications</em>, and included works that described these anomalies. Nonstrabismic binocular vision anomalies are classified as accommodative and vergence anomalies. There are three different major types of accommodative anomalies, namely accommodative insufficiency, accommodative infacility (accommodative inertia), and accommodative excess (accommodative spasm), and seven different types of vergence anomalies (convergence insufficiency, convergence excess, divergence insufficiency, divergence excess, basic esophoria, basic exophoria and fusional vergence dysfunctions), which are functional in origin. Functionally, there is a commonly reported interaction between accommodative and convergence insufficiency referred to as pseudoconvergence insufficiency. Accommodative paralysis (subtype of accommodative insufficiency) and vergence anomalies – <em>i.e.</em>, convergence paralysis, convergence spasm and divergence paralysis – are non-functional in origin with underlying systemic disease etiologies. Systemic convergence insufficiency, associated with subnormal accommodation, is a non-functional interaction between the accommodative and convergence insufficiency. The classification of nonstrabismic binocular vision anomalies is based on the description of the clinical signs and the underlying etiology either functional or non-functional in origin. Proper diagnosis and management involves investigation of the underlying etiology in addition to the battery of binocular vision test procedures.

scholarly journals Symptomatic vergence disorders in junior high school children in Ghana

2016 ◽  
Vol 75 (1) ◽  
Author(s):  
Charles Darko-Takyi ◽  
Naimah E. Khan ◽  
Urvashni Nirghini
Keyword(s):  
High School ◽  
Binocular Vision ◽  
Junior High School ◽  
Junior High ◽  
Cape Coast ◽  
Cross Sectional ◽  
School Based ◽  
Convergence Insufficiency ◽  
Vision Assessment ◽  
Divergence Insufficiency

Background: Optometrists in Ghana are hampered in performing comprehensive binocular vision assessments, because of the lack of appropriate instruments leading to a paucity of data on vergence disorders and their association with asthenopia among Ghanaian school children.Aim: To establish the prevalence of symptomatic vergence disorders among junior high school (JHS) children in Cape Coast Metropolis, Ghana, in their habitual (vision) states and investigate if there were any associations between these disorders and specific asthenopic symptoms.Methods: A prospective cross-sectional school-based study using a multistage sample of 627 participants aged 12–17 years from JHSs in Cape Coast Metropolis. Participants completed a reliable asthenopic symptoms questionnaire and 220 participants who expressed two or more severe or very severe symptoms were selected for comprehensive binocular vision assessment in their habitual vision state.Results: The prevalence of symptomatic vergence disorders among JHS children in Cape Coast Metropolis was 14.8%. For specific symptomatic vergence disorders, the prevalence was: 1.4% basic esophoria, 1.4% basic exophoria, 8.6% convergence insufficiency, 1.8% convergence excess, 0.8% fusional vergence dysfunctions and 0.8% divergence excess. No participant had symptomatic divergence insufficiency. The study revealed significant associations between some specific symptomatic vergence disorders and specific asthenopic symptoms even though all of these asthenopic symptoms overlapped in other vergence disorders.Conclusion: Presenting complaints of specific asthenopic symptoms does not differentiate between specific types of vergence disorders. A comprehensive binocular vision assessment is vital in the diagnosis and management of these disorders to relieve asthenopia.

The Presentations of Convergence Insufficiency among Young Adults (18-25 Years)

2021 ◽  
Vol 11 (7) ◽  
pp. 235-242
Author(s):  
Jacqueline E. Obioma-Elemba ◽  
Nnenne U. Onu ◽  
Okechi U. Amaechi
Keyword(s):  
Young Adults ◽  
Binocular Vision ◽  
Clinical Signs ◽  
Cross Sectional Study ◽  
State University ◽  
Blurred Vision ◽  
Cross Sectional ◽  
Imo State ◽  
Convergence Insufficiency ◽  
Study Population

Convergence Insufficiency is a major binocular vision dysfunction commonly found among the youth. The prevalence of convergence insufficiency has been studied extensively; however there are limited data available on the prevalence of the various presentations of convergence insufficiency among young adults. Convergence insufficiency is associated with symptoms such as fatigue, blurred vision at near, intermittent diplopia at near, “eye strain,” tension in and around the eyes, and the sensation of the print moving while reading. However, convergence insufficiency may present with or without symptoms. The exact prevalence of convergence insufficiency is not known. This study assessed the various presentations of convergence insufficiency among the young adults (aged 18 – 25 years) within the Imo State University community, Owerri, Nigeria, using a cross-sectional study design. Through purposive sampling, a sample size of 162 participants was used for this study after screening and pre-assessment. The Convergence Insufficiency Symptom Survey (CISS), the near point of convergence test, the Von Graefe phoria tests (at far and at near) and the positive fusional vergence tests were administered to all of the study participants. Convergence insufficiency among the young adults of Imo State University presented with symptoms (without clinical signs, 14.2%; with clinical signs, 16.6%) and without symptoms convergence insufficiency (27.8%). The study revealed that convergence insufficiency with symptoms was the more prevalent presentation of convergence insufficiency within the study population. A high percentage of young adults within the study population tested positive for convergence insufficiency, presenting with symptoms (with or without clinical signs) or without symptoms. Key words: Binocular vision, convergence insufficiency, young adult, symptoms, diplopia, phoria.

scholarly journals Vergence and Accommodative Dysfunctions in Emmetropic and Myopic Chinese Young Adults

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Martin Ming-Leung Ma ◽  
Anna Chwee Hong Yeo ◽  
Mitchell Scheiman ◽  
Xiang Chen
Keyword(s):  
Binocular Vision ◽  
Refractive Error ◽  
Linear Trend ◽  
Common Finding ◽  
Sample Population ◽  
Chi Square ◽  
Cross Sectional ◽  
Convergence Insufficiency ◽  
Chinese Young Adults ◽  
Divergence Insufficiency

Purpose. To investigate the association between refractive error and common binocular vision and accommodative dysfunctions in Chinese adults and to report the percentage of these disorders in this sample population. Methods. This was a single-site, prospective cross-sectional clinic-based study. A total of 415 Chinese participants aged between 21 and 38 years were grouped into 4 refractive error groups (emmetropia, low, moderate, and high myopia) based on the spherical equivalent power of noncycloplegic refraction. Baseline testing including binocular vision and accommodative testing was performed on all eligible participants. A multiple-sign classification system was used to analyze these data for the diagnosis of common nonstrabismic binocular vision and accommodative dysfunctions. Associations between the diagnosis and refractive error groupings were examined by the chi-square test for the linear trend. Results. Associations with refractive error groupings were found for convergence insufficiency (p=0.008, r = −0.13) and divergence insufficiency (p=0.008, r = 0.131). The 3 most common dysfunctions in this sample population were basic exophoria (10.8%), convergence insufficiency (9.6%), and divergence insufficiency (7.0%). Approximately 40% of the sample population demonstrated at least one type of binocular vision dysfunction. Conclusion. Convergence insufficiency and divergence insufficiency were associated with refractive error groupings. Binocular vision dysfunction was a common finding in this sample population.

scholarly journals Convergence Insufficiency - Perception Error: A Review Article

2020 ◽  
Vol 4 (2) ◽  
Keyword(s):  
Binocular Vision ◽  
Reading Performance ◽  
Vision Disorders ◽  
Eye Care ◽  
Visual Discomfort ◽  
Convergence Insufficiency ◽  
Single Vision ◽  
Vision Assessment ◽  
Proper Diagnosis ◽  
Binocular Single Vision

Ocular asthenopia associated with headaches and visual discomfort are the major complaints, clients have these days. Intensive near and digital works have brought many non-strabismic binocular vision disorders (NSBVD) in the clients. Convergence insufficiency (CI) is one of the most prevalent NSBVD. CI is a binocular vision dysfunction, characterized by the patient’s inability to accurately converge, or sustain accurate convergence when focusing on near objects. Apart from visual symptoms, CI is known to have effects on a children’s academics and a person’s daily life. In addition to visual discomfort, children with CI report symptoms affecting reading performance, such as loss of pace, loss of concentration, reading slowly, and trouble remembering what was read. Proper diagnosis of convergence insufficiency is simple, but it has been complicated by the unavailability of essential orthoptic tools; the attitude of practitioner and their knowledge adds to the hurdle. Why don’t we introduce term “CI Suspect” like “Glaucoma-Suspect” so that every individual if matches one or more criteria for CI diagnosis is subjected undergo a complete binocular single vision assessment? This will properly diagnose and manage the case and also make orthoptics as a proper sub-specialty for eye care practitioners.

scholarly journals Refractive and binocular vision status of optometry students, Ghana

2016 ◽  
Vol 5 (2) ◽  
pp. 24-29
Author(s):  
C. Darko-Takyi ◽  
A. Owusu-Ansah ◽  
C. Appiah-Eduenu ◽  
E.K. Abu ◽  
S.B. Boadi-Kusi ◽  
...  
Keyword(s):  
Binocular Vision ◽  
Cross Sectional Study ◽  
Refractive Errors ◽  
Biomedical Sciences ◽  
Cape Coast ◽  
Cross Sectional ◽  
Exact Test ◽  
Convergence Insufficiency ◽  
Divergence Insufficiency ◽  
Optometry Students

To investigate the refractive and non-strabismic binocular vision status of Optometry students in University of Cape Coast, Ghana and to establish any associations between these conditions. A cross sectional study of 105 Optometry students were taken through a comprehensive optometric examination to investigate the refractive and non-strabismic binocular vision status. Fisher’s exact test (IBM SPSS version 21) was used to assess association between these conditions. Prevalence of refractive error and non-strabismic binocular vision dysfunctions were 59.0% and 34.3% respectively. Prevalence of specific refractive errors were 17.1% myopia, 19.0% hyperopia and 22.9% astigmatism. Non-strabismic accommodative and vergence dysfunctions were found to be 21.9% and 12.4% respectively. Specific types of accommodative and vergence disorders were as follows: accommodative fatigue (8.6%), accommodative infacility (6.7%), accommodative insufficiency (4.7%) and accommodative excess (1.9%), convergence insufficiency (1.9%), convergence excess (1.0%), divergence insufficiency (2.9%), basic exophoria (1.9%), and basic esophoria (4.7%). There was a significant association between refractive errors in general and accommodative fatigue (p = 0.030) and between myopia and accommodative excess (p= 0.028). It is critical that potential primary eye care practitioners become aware of their refractive and non-strabismic binocular vision status.Journal of Medical and Biomedical Sciences (2016) 5(2), 24-29

Dual stain kit for the microscopic gram classification of ocular infection bacteria

1993 ◽  
Vol 51 ◽  
pp. 248-249
Author(s):  
Jacob S. Hanker ◽  
Dale N. Holdren ◽  
Kenneth L. Cohen ◽  
Beverly L. Giammara
Keyword(s):  
Contact Lenses ◽  
Ocular Infection ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
Gram Staining ◽  
Ocular Infections ◽  
Different Types ◽  
Culture Positive ◽  
Increased Susceptibility

Keratitis and conjunctivitis (infections of the cornea or conjunctiva) are ocular infections caused by various bacteria, fungi, viruses or parasites; bacteria, however, are usually prominent. Systemic conditions such as alcoholism, diabetes, debilitating disease, AIDS and immunosuppressive therapy can lead to increased susceptibility but trauma and contact lens use are very important factors. Gram-negative bacteria are most frequently cultured in these situations and Pseudomonas aeruginosa is most usually isolated from culture-positive ulcers of patients using contact lenses. Smears for staining can be obtained with a special swab or spatula and Gram staining frequently guides choice of a therapeutic rinse prior to the report of the culture results upon which specific antibiotic therapy is based. In some cases staining of the direct smear may be diagnostic in situations where the culture will not grow. In these cases different types of stains occasionally assist in guiding therapy.

Explanatory Power for Medical Expert Systems: Studies in the Representation of Causal Relationships for Clinical Consultations

1982 ◽  
Vol 21 (03) ◽  
pp. 127-136 ◽  
Author(s):  
J. W. Wallis ◽  
E. H. Shortliffe
Keyword(s):  
Explanatory Power ◽  
Prototype System ◽  
Inference Rules ◽  
Medical Expert ◽  
Comprehensive Knowledge ◽  
Different Types ◽  
Medical Expert Systems ◽  
Explanation System ◽  
Systems Studies

This paper reports on experiments designed to identify and implement mechanisms for enhancing the explanation capabilities of reasoning programs for medical consultation. The goals of an explanation system are discussed, as is the additional knowledge needed to meet these goals in a medical domain. We have focussed on the generation of explanations that are appropriate for different types of system users. This task requires a knowledge of what is complex and what is important; it is further strengthened by a classification of the associations or causal mechanisms inherent in the inference rules. A causal representation can also be used to aid in refining a comprehensive knowledge base so that the reasoning and explanations are more adequate. We describe a prototype system which reasons from causal inference rules and generates explanations that are appropriate for the user.

scholarly journals Deep Learning Methods for Classification of Certain Abnormalities in Echocardiography

Electronics ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 495
Author(s):  
Imayanmosha Wahlang ◽  
Arnab Kumar Maji ◽  
Goutam Saha ◽  
Prasun Chakrabarti ◽  
Michal Jasinski ◽  
...  
Keyword(s):  
Deep Learning ◽  
Short Term Memory ◽  
Support Vector ◽  
Variational Autoencoder ◽  
Different Types ◽  
Static Images ◽  
Long Short Term Memory ◽  
2D And 3D ◽  
Better Than

This article experiments with deep learning methodologies in echocardiogram (echo), a promising and vigorously researched technique in the preponderance field. This paper involves two different kinds of classification in the echo. Firstly, classification into normal (absence of abnormalities) or abnormal (presence of abnormalities) has been done, using 2D echo images, 3D Doppler images, and videographic images. Secondly, based on different types of regurgitation, namely, Mitral Regurgitation (MR), Aortic Regurgitation (AR), Tricuspid Regurgitation (TR), and a combination of the three types of regurgitation are classified using videographic echo images. Two deep-learning methodologies are used for these purposes, a Recurrent Neural Network (RNN) based methodology (Long Short Term Memory (LSTM)) and an Autoencoder based methodology (Variational AutoEncoder (VAE)). The use of videographic images distinguished this work from the existing work using SVM (Support Vector Machine) and also application of deep-learning methodologies is the first of many in this particular field. It was found that deep-learning methodologies perform better than SVM methodology in normal or abnormal classification. Overall, VAE performs better in 2D and 3D Doppler images (static images) while LSTM performs better in the case of videographic images.

scholarly journals Preventing corneal blindness caused by keratitis using artificial intelligence

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Zhongwen Li ◽  
Jiewei Jiang ◽  
Kuan Chen ◽  
Qianqian Chen ◽  
Qinxiang Zheng ◽  
...  
Keyword(s):  
Early Diagnosis ◽  
Vision Loss ◽  
Learning System ◽  
Automated Classification ◽  
Slit Lamp ◽  
Resource Limited ◽  
The World ◽  
Different Types ◽  
Corneal Blindness

AbstractKeratitis is the main cause of corneal blindness worldwide. Most vision loss caused by keratitis can be avoidable via early detection and treatment. The diagnosis of keratitis often requires skilled ophthalmologists. However, the world is short of ophthalmologists, especially in resource-limited settings, making the early diagnosis of keratitis challenging. Here, we develop a deep learning system for the automated classification of keratitis, other cornea abnormalities, and normal cornea based on 6,567 slit-lamp images. Our system exhibits remarkable performance in cornea images captured by the different types of digital slit lamp cameras and a smartphone with the super macro mode (all AUCs>0.96). The comparable sensitivity and specificity in keratitis detection are observed between the system and experienced cornea specialists. Our system has the potential to be applied to both digital slit lamp cameras and smartphones to promote the early diagnosis and treatment of keratitis, preventing the corneal blindness caused by keratitis.

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