Visual and binocular status in elementary school children with a reading problem

Clinical practice patterns for assessing children with learning difficulties: survey of eye health care professionals

CLINICAL RELEVANCE

Understanding what aspects of vision or binocular vision may affect learning, and how these are assessed, is important for the eye health care professional assessing children with learning difficulties. It is vital that visual dysfunction is identified or excluded in these patients to ensure targeted and timely intervention.

BACKGROUND

The aim of this study was to investigate similarities and differences between eye care professionals in the knowledge, attitudes and practice patterns, when evaluating children with learning difficulties.

METHODS

This study was a cross-occupational, cross-sectional, predominantly quantitative internet-based survey. Ophthalmologists, optometrists, and orthoptists working in Australia were eligible to participate. A questionnaire comprising of 31 multiple-choice questions with up to 19 additional branching questions was distributed using REDCap in September 2022.

RESULTS

A total of 130 responses were analysed (6 ophthalmologists, 84 orthoptists and 40 optometrists of whom 9 were practicing behavioural vision care). Most respondents assessed distance visual acuity (95%), near stereoacuity (85%), presence of strabismus (88%) and ocular movements (91%). Near vision was assessed less often (65%). Optometrists were most likely to measure colour vision (p < 0.002), accommodation and undertake a subjective refraction (each p < 0.001). Ophthalmologists were least likely to measure convergence (p = 0.041) but more likely to undertake a cycloplegic refraction (p = 0.044). More optometrists practicing behavioural vision care reported testing binocular vision (p = 0.026), fusional vergence (p < 0.001), saccades (p = 0.066), and smooth pursuit (p = 0.050) than other professions. There was a positive correlation between frequency and confidence level when assessing children with learning difficulties (ρ = 0.64). Respondents referred to paediatricians (39%), speech pathologists (30%), educational psychologists (29%) and general practitioners (29%).

CONCLUSION

Despite similarities across occupations, there were differences in testing the vision and binocular functions of children with learning difficulties. Future research should aim to establish minimum standards for assessing this patient cohort to ensure consistent and relevant assessment.

The Impact of the Test Dissociation on the Binocular Balance of Children

PURPOSE

this research compared the dissociated phoria at near and distance fixation in free space using the Howell test, alternate Cover test, and Thorington test.

METHODS

220 healthy Mexican children (mean age 8.3±2.5 years) participated in this study. Phorias were quantified at both distances using each test, from the least to the most disruptive. The stereopsis degree and near point of convergence (break/recovery) were analyzed to understand their role in the visual system's sensorimotor balance.

RESULTS

statistically significant differences were found among techniques, with a higher congruence for the EF. However, only the Howell and Thorington tests can be interchanged. The break value and near exophoria relate to each other and affect the stereopsis degree, whereas age is associated with the stereopsis degree and break value.

CONCLUSIONS

the three techniques cannot be interchanged except for the Howell and Thorington test for the EF at far. The differences in the mode of dissociation could relate to the results.

The Neurological Basis of Developmental Dyslexia and Related Disorders: A Reappraisal of the Temporal Hypothesis, Twenty Years on

In a now-classic article published a couple of decades ago (Brain, 2000; 123: 2373-2399), I proposed an "extended temporal processing deficit hypothesis of dyslexia", suggesting that a deficit in temporal processing could explain not only language-related peculiarities usually noticed in dyslexic children, but also a wider range of symptoms related to impaired processing of time in general. In the present review paper, I will revisit this "historical" hypothesis both in the light of a new clinical perspective, including the central yet poorly explained notion of comorbidity, and also taking a new look at the most recent experimental work, mainly focusing on brain imaging data. First, consistent with daily clinical practice, I propose to distinguish three groups of children who fail to learn to read, of fairly equal occurrence, who share the same initial presentation (difficulty in mastering the rules of grapheme-phoneme correspondence) but with differing associated signs and/or comorbid conditions (language disorders in the first group, attentional deficits in the second one, and motor coordination problems in the last one), thus suggesting, at least in part, potentially different triggering mechanisms. It is then suggested, in the light of brain imaging information available to date, that the three main clinical presentations/associations of cognitive impairments that compromise reading skills acquisition correspond to three distinct patterns of miswiring or "disconnectivity" in specific brain networks which have in common their involvement in the process of learning and their heavy reliance on temporal features of information processing. With reference to the classic temporal processing deficit of dyslexia and to recent evidence of an inability of the dyslexic brain to achieve adequate coupling of oscillatory brain activity to the temporal features of external events, a general model is proposed according to which a common mechanism of temporal uncoupling between various disconnected-and/or mis-wired-processors may account for distinct forms of specific learning disorders, with reading impairment being a more or less constant feature. Finally, the potential therapeutic implications of such a view are considered, with special emphasis on methods seeking to enhance cross-modal connectivity between separate brain systems, including those using rhythmic and musical training in dyslexic patients.

Correlations between clinical measures and symptoms: Report 2: Accommodative and vergence measures with symptoms

AIM

The aim of this study was to explore associations among clinical measures of accommodation and vergences with symptoms, which could facilitate the validation of the Convergence Insufficiency Symptoms Survey to screen for deficient clinical measures.

METHODS

Using a multi-stage random cluster sampling, 1211 high school students (481 males and 730 females) between 13 and 18 years of age were selected and examined. Visual acuity, stereoacuity and suppression, refractive errors, near point of convergence, heterophoria and fusional vergences, as well as, amplitude of accommodation, accommodative response, facility and relative accommodation were evaluated. The validity of the Convergence Insufficiency Symptoms Survey to distinguish between children with and those without anomalies in the clinical measures were characterized using the Receiver Operation Curve, sensitivity and specificity of the tests.

RESULTS

The overall mean and standard deviation for symptoms score was 27.38 ± 11.04. Deficient accommodative measures revealed worse symptoms scores than did deficient vergence measures and children with deficient clinical measures had significantly higher mean symptoms scores. (p = 0.001) However, the correlations between defective clinical measures and symptoms were significant but relatively weak. The Receiver Operation Curve showed that the clinical measures with the highest sensitivities using the CISS (≥16) were: reduced amplitude of accommodation 0.63, 95% Confidence interval, 0.59-0.68%) accommodative facility 0.62 (95% Confidence interval, 0.58-0.67) and near point of convergence 0.60 (95% Confidence interval, 0.53-0.67).

CONCLUSION

Deficient clinical measures and symptoms of asthenopia are prevalent and correlated in the sample of school children studied. Overall, findings suggest that high school children with deficient clinical measures may be symptomatic when they perform intense near task compared to those without deficiencies. In addition, although validated for convergence insufficiency, the Convergence Insufficiency Symptoms Survey could barely distinguish between children with and without defective clinical measures. Findings highlight the need for and provide baseline data towards possible validation of a fast and reliable screening tool for vision anomalies. Further studies on similar populations are needed to confirm these findings and add to knowledge base.

The Influence of COVID-19 Isolation on Physical Activity Habits and Its Relationship with Convergence Insufficiency

The purpose of this work is to evaluate the effects of confinement due to COVID-19 isolation on visual function, considering insufficient convergence as one of the possible effects of living the whole day in a reduced space. We pass a Convergence Insufficiency Symptom Survey (CISS) among 235 people to detect their habits before and after 25 confinement days. The data collection protocol consisted on a Google forms questionnaire included two parts: the first with current data (isolation period) and a second with pre-isolation period data. Differences between the pre-isolation and isolation period were calculated using the related paired T-tests. When statistically significant differences were found, the effect size was estimated using the Cohen’s d index (d). The reduction in physical activity levels during confinement were related to the increase in total number of minutes of screen consumption from 433.49 min to 623.97 min per day (d = 0.67; 44.01%). The CISS scores were increased by more than 43% during confinement. The increase in convergence insufficiency was 100% after the studied isolation period of 25 days. The 92.19% increase in television use during 25 days of confinement is not responsible for the increase in convergence insufficiency. However, due to the increase in the use of PCs in this period, there is a notable increase in convergence insufficiency. Therefore, we can conclude that not all increases in tasks with electronic devices are responsible for the increase in convergence insufficiency.

Evaluation of a Novel Quality of Life Scale for Schoolchildren with Nonstrabismic Binocular Vision Anomalies

BACKGROUND

The professional Quality of Life Scale (QLS) can provide a valuable reference for the diagnosis of visual function anomalies. In the present study, we aimed to design a novel QLS to specially quantify the life quality of schoolchildren with nonstrabismic binocular vision anomalies (NSBVAs) in China.

METHODS

The novel QLS, named QOL-CVF20, was established based on classical vision-related scales and the administration of the questionnaire to 116 schoolchildren with NSBVAs and 100 healthy schoolchildren in China. The diagnostic reference value between QOL-CVF20 and VF-14 was evaluated on the questionnaires to 240 schoolchildren with NSBVAs and 238 healthy schoolchildren.

RESULTS

All the subjects could complete the QOL-CVF20 questionnaires independently. QOL-CVF20 had good structural validity, content validity, and discriminant validity, when it was applied in Chinese schoolchildren. The average score of the NSBVA group was significantly lower than that of the control group (49.0 ± 6.9 vs. 69.7 ± 6.7, respectively; P < 0.01). Moreover, the average score of cured NSBVA schoolchildren after treatment (61.8 ± 22.6) was significantly improved (P < 0.01). Receiver operating characteristic curve analysis showed that QOL-CVF20 reflected strong separation between the NSBVA and healthy groups (AUC = 0.901). Meanwhile, QOL-CVF20 could detect individuals with NSBVAs with specificity of 0.847 and sensitivity of 0.846. The critical value of 58.50 in QOL-CVF20 could be effectively applied for quality of life assessment in schoolchildren with NSBVAs.

CONCLUSIONS

QOL-CVF20 could quantify the life quality of schoolchildren with NSBVAs and might be served as a valuable reference for early diagnosis and clinical evaluation of NSBVAs.

Scottish Pre-School Vision Screening - First 3 Years of National Data

INTRODUCTION

Pre-school orthoptic vision screening (POVS) was implemented by the Scottish government and is a standardised assessment to promote early detection of visual problems in children. The target conditions are amblyopia, refractive errors and strabismus. We present the preliminary findings for the first three years of the screening program.

METHODS

The data from POVS was collected retrospectively. The data includes screening years 2013 to 2016 inclusive. Data was collected from each health board in Scotland. We report the coverage, referral rate, true positives and positive predictive values.

RESULTS

A total of 167,962 children were due to have vision screening over the 3 screening years included in this paper. This figure does not include the children that opted out of the eye test (mean opt-out rate 1.8%) and children that already attend the hospital eye service (mean already attend rate 3.1%). The POVS program had a mean coverage of 85.5%, ranging from 63.7% to 94.8% between health boards. Over the 3 year screening period, the mean referral rate was found to be 17.9%. The mean true positive rate was 88.9%, and the mean positive predictive value was 86.9%.

CONCLUSION

The Scottish data set on pre-school orthoptic vision screening has shown excellent mean coverage. A consistently high true positive rate over the three screening years demonstrates it is a sensitive screening program, which is essential for the detection of visual problems in children.

Diagnosis of oculomotor anomalies in children with learning disorders

This systematic review presents the existing scientific evidence for oculomotor anomalies in children with three different types of learning disorders - namely, dyslexia, dyspraxia and attention deficit-hyperactivity disorder (ADHD). This review was registered in the PROSPERO database (registration number: 139317). The QUADAS-2 tool was used to systematically evaluate the quality of the diagnostic tests used in the evaluated studies and to confirm whether the oculomotor alterations observed in the different groups of children with various learning disorders had a consistent diagnostic basis. Using this tool, the design of the articles was well elaborated, although concerns exist regarding the selection of patients and the diagnostic criteria for the binocular conditions. All the studies reviewed conclude that a pattern of oculomotor anomalies exist in the groups of children with these three types of learning disorders compared to healthy children. However, there is a concern regarding the diagnostic methodology, as no clear range of normality for the parameters used to characterise ocular motility was identified and no gold standard or reference test has been defined. In future studies, this range of normality must be developed for different oculomotor skills, and a reference test (possibly video-oculography) for the measurement of these skills must be established.