Towards population screening for Cerebral Visual Impairment: Validity of the Five Questions and the CVI Questionnaire

Parent-reported problems in children with Cerebral Visual Impairment: Improving the discriminative ability from ADHD and dyslexia using screening inventories

Daily problems of children with Cerebral Visual Impairment (CVI) are often misinterpreted as symptoms of behavioural disorders or learning disabilities instead of higher order visual function (HOVF) deficits. It is difficult to differentiate between various paediatric clinical groups based on daily manifestations. We used two CVI inventories (V-CVI-I, HVFQI) and an ADHD questionnaire (AVL) to compare parent-reported visual and behavioural problems of children with CVI, ADHD, dyslexia and neurotypical children (Age 6-15, Verbal Intelligence > 70). Our results show a higher percentage of parent-reported visual problems in children with CVI compared to all other groups, which was not affected by their visual acuity levels. On most HOVF categories, a higher percentage of parent-reported visual problems was also found in children with ADHD or dyslexia compared to neurotypical children. Children with ADHD had significantly more parent-reported behavioural problems, but more behavioural problems were reported by the parents of children with CVI compared to neurotypical children as well. Our findings complicate using the existing inventories for initial screening and referral of children with potential CVI. We propose a shortened screening list to improve the potential differentiation between CVI and ADHD or dyslexia based on parent-reported visual problems in everyday life.

Neurological and Visual Outcomes in Infants and Toddlers Following Therapeutic Hypothermia for Neonatal Hypoxic-Ischemic Encephalopathy

BACKGROUND

The majority of studies have investigated neurodevelopmental outcomes, whereas visual impairment is less explored in children with a history of neonatal (hypoxic-ischemic) encephalopathy. Our aim was to perform a detailed neurological and visual assessment and also to investigate the presence of cerebral visual impairment in infants and toddlers with neonatal encephalopathy.

METHODS

Thirty participants with a history of neonatal encephalopathy, who had been hospitalized for therapeutic hypothermia, underwent a detailed neurological examination at age five to 36 months. Age-matched, 30 healthy children were also enrolled as a control group. All children in the study and control groups received neurological and a comprehensive ophthalmologic examination, including visual field and visual acuity. Presence of cerebral visual impairment was also evaluated clinically.

RESULTS

Rates of cerebral palsy, severe motor impairment, cognitive impairment, epilepsy, and cerebral visual impairment were found to be 20%, 10%, 15.3%, 10%, and 20%, respectively. When compared with healthy controls, oculomotor functions, pupillary light response, refractive parameters, anterior/posterior segment examinations, ocular visual impairment rates, and last, visual acuities were found similar. However, we found a statistically significant increase in visual field defects in our study group.

CONCLUSIONS

It could be better to perform a comprehensive ophthalmologic examination including visual field, visual acuity, and oculomotor functions by a pediatric ophthalmologist to accurately diagnose neurovisual deficits in infants following therapeutic hypothermia. Early identification and rehabilitation of the visual deficits might improve the neurodevelopment in these children.

Australian children with cerebral visual impairment: using what we know now to improve future approaches

PURPOSE

Little has been reported on Australian children with Cerebral Vision Impairment (CVI). This paper aims to present the outcome of an audit focussed on children with the primary diagnosis of CVI, using findings from the Australian Childhood Vision Impairment Register (ACVIR).

METHODS

Records on 132 children (49% girls, 51% boys) from ACVIR data gathered from both the child's parent/guardian and their eye health professional were reviewed. The child's demographics, level of vision impairment, birth history, diagnostic journey, secondary ocular diagnoses, comorbidities and low vision support were analyzed. Several correlations were investigated using a Kendall's tau-b analysis including the relationship between vision and age of diagnosis; level of vision and developmental delay; and age of suspicion of visual impairment and age of diagnosis.

RESULTS

The most common level of visual impairment was blindness (39%), and most children were suspected and diagnosed of visual impairment in the first 6 months of life. The majority of children were born full term (72%), weighing >2000gms (84%). Nearly half of the cohort of children (48%) had a secondary ocular diagnosis with 44% having nystagmus. The majority of children (80%) had additional health problems, and 85% of children had additional disabilities, with 79% having developmental delay.

CONCLUSION

While the findings of this audit cannot be generalized to a wider population of Australian children with CVI, the outcome encourages continued discussion on CVI, to explore comprehensive assessment approaches which facilitate timely and accurate diagnosis.

Validation of the Austin Assessment: A screening tool for cerebral visual impairment related visual issues

Cerebral visual impairment is the most common cause of vision impairment affecting children in the economically developed world with a prevalence rate of approximately 3.4%. Currently there are limited options for screening for cerebral visual impairment, resulting in many children going undiagnosed, especially those that have normal visual acuity. The aim of this research was to validate an iPad App called the Austin Assessment, which was developed as a potential screening tool for cerebral visual impairment related visual issues. The research involved three separate phases: (1) creating a database of normative ranges for children aged 5-18 across the different variables of the Austin Assessment, (2) using the Austin Assessment to screen children aged 5-13 to assess the effectiveness of the Austin Assessment as a screening tool for CVI related visual issues, and (3) conducting specific validation research assessing children using the Austin Assessment and an already validated visual search tool. Each phase used different quantitative research methodologies to help show the effectiveness of the Austin Assessment as a screening tool for cerebral visual impairment related visual issues. From phase one of the research, thresholds were established for three variables of the Austin Assessment for the age groupings of 5-8, 9-12 and 13-18. If a child meets one of these thresholds this indicates further assessment is required to determine if they do in fact have cerebral visual impairment related visual issues. Phase two identified 17 children out of 270 who had clinical findings indicating visual issues; potentially indicative of CVI; investigation into the nature of these visual issues is ongoing. Phase three found that the Austin Assessment has moderate diagnostic value for each age group, with good sensitivity and specificity, making it effective at distinguishing those children who have visual issues from those who have typical vision. Further investigation is needed to confirm this initial validation.

Occupational Therapy Assessments of Cortical or Cerebral Visual Impairment: A Systematic Review

IMPORTANCE

Cortical or cerebral visual impairment (CVI), a leading cause of visual dysfunction in children across the globe, can result in delayed development of fine and gross motor skills, functional mobility, and socialization, which affects all areas of occupation. No assessments are recommended for occupational therapy practitioners working with children with CVI.

OBJECTIVE

To appraise the measurement properties and clinical utility of CVI assessments appropriate for use by occupational therapy practitioners.

DATA SOURCES

MEDLINE via PubMed, Scopus, and Web of Science.

STUDY SELECTION AND DATA COLLECTION

We followed the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) guidelines for systematic reviews of patient-reported outcome measures for relevant studies.

FINDINGS

A total of 590 records yielded 15 studies of the measurement properties of 12 assessment tools, 8 patient-reported outcome measures and 4 clinician-reported or performance-based outcome measures. We report on the quality of measurement properties of 10 of the 12 outcome measures. None had high-quality evidence of content validity, structural validity, or test-retest reliability. Most had indeterminate internal consistency as a result of a lack of confirmatory factor analysis. Three instruments demonstrated high quality and sufficient construct validity.

CONCLUSIONS AND RELEVANCE

On the basis of the COSMIN guidelines, all 12 outcome measures have the potential to be recommended but require further study before definitive recommendations can be made. What This Article Adds: This is the first systematic review of assessments of CVI feasible for use by occupational therapy practitioners. High-quality studies of measurement properties are lacking. Further examination of the measurement properties of outcome measures is required.

Commentary: Profiling Children With Cerebral Visual Impairment (CVI) Using Multiple Methods of Assessment to Aid in Differential Diagnosis

PROFILING CHILDREN WITH CEREBRAL VISUAL IMPAIRMENT USING MULTIPLE METHODS OF ASSESSMENT TO AID IN DIFFERENTIAL DIAGNOSIS: Amanda H. Lueck , Gordon N. Dutton , Sylvie Chokron Seminars in Pediatric Neurology Volume 31, October 2019, Pages 5-14 Cerebral (cortical) visual impairment (CVI), the primary cause of visual impairment in chil dren in high-income countries, is increasing globally due to improved life-saving measures for premature and full-term infants. Yet the consequences of this condition are only begin ning to be understood and addressed. According to the topography, site, and the extent of the pathology, the deficit may variably concern central visual functions, visual field, percep tion of movement, visual analysis, visual exploration, attention, or visual memory, as well as visual guidance of movement. Each affected child has a unique clinical picture, which needs to be identified and individually profiled. This is probably the underlying reason that CVI is commonly underdiagnosed or misdiagnosed, especially in children, and, as a consequence, the full range of potential behavioral outcomes are not identified and adequately addressed. The present paper shows how the use of multiple methods of assessment can improve understanding of children with CVI.

Relationship between Sensory Processing Skills and Feeding Behaviors in Children Aged 3-6 Years with Cerebral Palsy with Cerebral Visual Impairment

The current study aimed to examine the relationship between sensory processing skills and feeding behavior in cerebral palsy (CP) children aged 3-6 years with cerebral visual impairment (CVI). A total of ninety mothers participated in the study in three groups: thirty mothers of children with CP with CVI, thirty mothers of children with CP without CVI, and thirty mothers of children with typical development (TD). The sensory processing skill of the children was evaluated with the Sensory Profile (SP), and feeding behavior was evaluated with the the Behavioral Pediatric Feeding Assessment Scale (BPFAS). In the triple comparison, a significant difference was found between the groups in all SP parameter and BPFAS scores (p < 0.001). Post hoc analysis revealed statistically significant differences between the groups in all parameters (p < 0.001). Feeding problems were detected in 65% of all groups. In the correlation analysis, a significant relationship was found between all parameters of the SP and the BPFAS (p < 0.05). In terms of sensory processing skills and feeding status, it was determined that children with CVI with CP had more problems than children with CP without CVI, and children with CP without CVI had more problems than children with TD. With these results, it was concluded that sensory processing problems affect feeding status, and visual impairment causes both sensory problems and feeding problems.

Clinical assessment, investigation, diagnosis and initial management of cerebral visual impairment: a consensus practice guide

Cerebral Visual Impairment (CVI) is a common condition in the UK. Patients with conditions associated with CVI are frequently seen in paediatric ophthalmology clinics offering eye care professionals an opportunity to identify children proactively. In most cases CVI occurs as part of a neurodevelopmental condition or as a feature of multiple and complex disabilities. However, CVI can also be seen in children with apparently typical development. In some cases, high contrast visual acuity is normal and in other cases severely impaired. As such, identification of CVI requires evaluation of aspects of visual performance beyond high contrast acuity and consideration that visual function of those with CVI may fluctuate. Few paediatric ophthalmologists have received formal training in CVI. The detection and diagnosis of CVI varies across the UK and patients report hugely different experiences. A diagnosis of CVI is made based on professional clinical judgement and it is recognised that individual perspectives and local practice in the specific methodologies of assessment will vary. A systematic review and survey of professionals is underway to attempt to reach agreement on diagnostic criteria. Nonetheless, established pathways and published protocols can offer guidance on how a paediatric ophthalmology service can approach assessment of the child with suspected CVI. The purpose of this paper is to present a summary of research and clinical practice methods for detecting and diagnosing CVI in a paediatric ophthalmology outpatient setting. It represents current understanding of the topic and acknowledges the evolving nature of both practice and the evidence-base. A rapid literature review was undertaken to identify articles relating to clinical investigation of children with CVI. A focus group of QTVI and subject matter experts from sight loss charities was undertaken to address areas which were not covered by the literature review.

A Scoping Review of Intervention for Pediatric Cerebral Visual Impairment: Calling All Pediatric Occupational Therapists

Cerebral visual impairment is the leading cause of low vision in children, and functional gains can be achieved with intervention. To date there exists no evidence-based intervention protocol to guide rehabilitation therapists. This scoping review was conducted to synthesize the evidence currently available and explore current interventions in order to guide future research. This review identified five types of interventions for cerebral visual impairment; habilitation, visual stimulation, video game, color tent, and medical and also evidenced the need for standardized, objective measures of function for this population.

[Formula: see text] Visual selective attention and visual search performance in children with CVI, ADHD, and Dyslexia: a scoping review

Visual selective attention refers to the selection of relevant visual elements in a scene whilst ignoring irrelevant visual elements. Visual Selective Attention Dysfunctions (VSAD) are prevalent in children with Cerebral Visual Impairment (CVI), Attention Deficit Hyperactivity Disorder (ADHD), and Dyslexia. An important issue in the pediatric neuropsychological practice is how to discriminate between the task performance of these populations. We conducted a scoping review of the literature on visual search performance (VSP) in children with CVI, ADHD, and Dyslexia, aged 6-12 years. After a systematic selection process, 35 studies were included. Results suggest that all patient groups have some degree of impaired VSP compared to typically developing children. Children with CVI tend to react slower and less accurately. VSP impairments in children with ADHD are characterized by poor accuracy rather than reaction time. Children with Dyslexia tend to be slower and less accurate, depending on stimulus type. Besides VSAD, it is argued that other neurocognitive mechanisms might influence VSP, such as speed-accuracy trade-off or an executive functioning deficit in ADHD and a phonological deficit in Dyslexia. This paper further discusses the differences and similarities in visual search performance between the groups. The sparse data in children with an official diagnosis of CVI and the technical inconclusive data on children with ADHD and Dyslexia demonstrate complexity of discriminating between these populations in clinical practice based on VSP. New and more quantitative VSP parameters, such as eye tracking-based measures, may contribute to a refined classification among CVI, ADHD, and Dyslexia.

Visual and cognitive profiles in children with and without cerebral visual impairment

Reliable differentiation of visual-perceptual difficulties in children with and without cerebral visual impairment (CVI) can often pose a diagnostic challenge. We, therefore, assessed the visual-perceptual profile in 94 children with and 77 children without suspected CVI between the ages of 8 and 17 years in a non-clinical setting, using a screening questionnaire and standardized visual-perceptual tests. Children with suspected CVI reported more frequently greater visual difficulties, had lower visual acuity, and were significantly impaired in visual search tests, in visual form and object perception, in visual space perception, and in visual text processing. There were no significant differences between groups in stereopsis, fixation stability, motility, horizontal saccadic eye movements, and convergence and accommodation. Cognitive performance in auditory attention and verbal short-term and working memory was similar in both groups. Our results indicate that the use of an appropriate questionnaire and specific visual-perceptual tests enables valid diagnostic detection of CVI. The additional use of cognitive tests also allows differentiation between primary and secondary impairments in visual perception.

Deficits in Face Recognition and Consequent Quality-of-Life Factors in Individuals with Cerebral Visual Impairment

Individuals with cerebral visual impairment (CVI) frequently report challenges with face recognition, and subsequent difficulties with social interactions. However, there is limited empirical evidence supporting poor face recognition in individuals with CVI and the potential impact on social-emotional quality-of-life factors. Moreover, it is unclear whether any difficulties with face recognition represent a broader ventral stream dysfunction. In this web-based study, data from a face recognition task, a glass pattern detection task, and the Strengths and Difficulties Questionnaire (SDQ) were analyzed from 16 participants with CVI and 25 controls. In addition, participants completed a subset of questions from the CVI Inventory to provide a self-report of potential areas of visual perception that participants found challenging. The results demonstrate a significant impairment in the performance of a face recognition task in participants with CVI compared to controls, which was not observed for the glass pattern task. Specifically, we observed a significant increase in threshold, reduction in the proportion correct, and an increase in response time for the faces, but not for the glass pattern task. Participants with CVI also reported a significant increase in sub-scores of the SDQ for emotional problems and internalizing scores after adjusting for the potential confounding effects of age. Finally, individuals with CVI also reported a greater number of difficulties on items from the CVI Inventory, specifically the five questions and those related to face and object recognition. Together, these results indicate that individuals with CVI may demonstrate significant difficulties with face recognition, which may be linked to quality-of-life factors. This evidence suggests that targeted evaluations of face recognition are warranted in all individuals with CVI, regardless of their age.

Clinimetric properties of visuo-perceptual and visuo-cognitive assessment tools used for children with cerebral visual impairment and cerebral palsy or developmental delay: a systematic review

PURPOSE

The aim of this systematic review is to evaluate the psychometrics and clinical utility of visuo-perceptual and visuo-cognitive assessment tools in children with cerebral visual impairment (CVI) and cerebral palsy (CP) or neurodevelopmental delay (DD).

MATERIALS AND METHODS

Five databases (PubMed, EMBASE, SCOPUS, CINAHL, and Cochrane Database) were comprehensively searched from 1970 till June 2021. The PRISMA checklist was utilised to report on the process of selecting eligible papers. The methodological quality of included studies was evaluated using COnsenus-based Standards for the selection of health Measurement INstrument (COSMIN) checklist.

RESULTS

Of the 26 assessment tools identified, only seven tools had psychometric evidence supporting their use. Based on COSMIN guidelines, 60% of included studies were rated as inadequate or doubtful for their methodological quality of measurement properties, with equal number being rated as indeterminate on the overall rating.

CONCLUSIONS

Cerebral visual impairment due to its varied clinical presentation is often missed in children with CP and DD. There is a paucity of studies reporting on the validity and reliability of functional vision tools. Further studies are needed to conduct high-quality psychometric reporting using the updated COSMIN guidelines to identify appropriate functional vision tools for children with CP or DD.Implications for rehabilitationThere are paucity of studies evaluating the validity and reliability of existing perceptual and cognitive assessment tools in children with cerebral visual impairment (CVI) and cerebral palsy (CP).Development of age-appropriate assessment tools evaluating all aspects of functional vision will assist in providing more holistic child-centric rehabilitation programs.A combination of detailed perinatal history, direct observation, and clinical assessments of functional vision are important to recognise CVI in children with CP.

The Multidisciplinary Guidelines for Diagnosis and Referral in Cerebral Visual Impairment

Introduction

Cerebral visual impairment (CVI) is an important cause of visual impairment in western countries. Perinatal hypoxic-ischemic damage is the most frequent cause of CVI but CVI can also be the result of a genetic disorder. The majority of children with CVI have cerebral palsy and/or developmental delay. Early diagnosis is crucial; however, there is a need for consensus on evidence based diagnostic tools and referral criteria. The aim of this study is to develop guidelines for diagnosis and referral in CVI according to the grade method.

Patients and Methods

We developed the guidelines according to the GRADE method 5 searches on CVI (children, developmental age ≤ 18 years) were performed in the databases Medline, Embase, and Psychinfo, each with a distinct topic.

Results

Based on evidence articles were selected on five topics: 1. Medical history and CVI-questionnaires 23 (out of 1,007). 2. Ophthalmological and orthoptic assessment 37 (out of 816). 3. Neuropsychological assessment 5 (out of 716). 4. Neuroradiological evaluation and magnetic resonance imaging (MRI) 9 (out of 723). 5. Genetic assessment 5 (out of 458).

Conclusion

In medical history taking, prematurity low birth weight and APGAR (Appearance, Pulse, Grimace, Activity, Respiration) Scores (<5) are important. Different questionnaires are advised for children under the age of 3 years, older children and for specific risk groups (extremely preterm). In ophthalmological examination, eye movements, specially saccades, accommodation, crowding, contrast sensitivity and visual fields should be evaluated. OCT can show objective signs of trans-synaptic degeneration and abnormalities in fixation and saccades can be measured with eye tracking. Screening of visual perceptive functioning is recommended and can be directive for further assessment. MRI findings in CVI in Cerebral Palsy can be structured in five groups: Brain maldevelopment, white and gray matter lesions, postnatal lesions and a normal MRI. In children with CVI and periventricular leukomalacia, brain lesion severity correlates with visual function impairment. A differentiation can be made between cortical and subcortical damage and related visual function impairment. Additional assessments (neurological or genetic) can be necessary to complete the diagnosis of CVI and/or to reveal the etiology.

Visual Function and Neuropsychological Profile in Children with Cerebral Visual Impairment

Cerebral Visual Impairment (CVI) has become the leading cause of children’s visual impairment in developed countries. Since CVI may negatively affect neuropsychomotor development, an early diagnosis and characterization become fundamental to define effective habilitation approaches. To date, there is a lack of standardized diagnostic methods to assess CVI in children, and the role of visual functions in children’s neuropsychological profiles has been poorly investigated. In the present paper, we aim to describe the clinical and neuropsychological profiles and to investigate the possible effects of visual functions on neuropsychological performance of a cohort of children diagnosed with CVI. Fifty-one children with CVI were included in our retrospective analysis (inclusion criteria: verbal IQ > 70 in Wechsler scales; absence of significant ocular involvement). For each participant, we collected data on neuropsychological assessment (i.e., cognitive, cognitive visual, and learning abilities), basic visual functions (e.g., Best Corrected Visual Acuity—BCVA, contrast sensitivity, and ocular motor abilities) and global development features (e.g., neurological signs and motor development delay) based on standardized tests, according to patients’ ages. The results showed that oculomotor dysfunction involving saccades and smooth pursuit may be a core symptom of CVI and might have a significant impact on cognitive visual and other neuropsychological abilities. Furthermore, visual acuity and contrast sensitivity may influence cognitive, cognitive visual, and academic performances. Our findings suggest the importance of a comprehensive assessment of both visual and neuropsychological functions in children when CVI is suspected, which is needed to provide a more comprehensive functional profile and define the best habilitation strategy to sustain functional vision.

Higher Visual Function Deficits in Children With Cerebral Visual Impairment and Good Visual Acuity

In clinical practice Cerebral Visual Impairment (CVI) is typically diagnosed by observation of abnormal visually guided behaviors which indicate higher visual function deficits (HVFDs) suggesting abnormal brain development or brain damage in a child with a suitable clinical history. HVFDs can occur even in the presence of good visual acuity and may remain undiagnosed because the good visual acuity does not prompt further investigation. This leads to a lack of understanding of the child's visual perceptual difficulties. In a prospective study, we determined the spectrum of HVFDs in a group of children with history suggestive of brain damage or disruption of brain development and an independent diagnosis of CVI in comparison with typically developing children with a structured 51 question inventory, the Higher Visual Function Question Inventory (HVFQI-51) adapted from the Cerebral Vision Impairment Inventory, CVI-I. Here, we show that the HVFQI-51 can detect a range of HVFDs in children with CVI with good visual acuity and clearly distinguishes these children from typically developing children. HVFDs in our study group could mostly be attributed to dorsal stream visual processing dysfunction though the spectrum varied between children. We report on the inclusion of the "not applicable" response option in analysis providing a picture of HVFDs more in tune with the overall disability of each child. We also propose a subset of 11 questions (Top-11) which discriminate between children with CVI vs. behaviors seen in typical children: this provides both a potential screening tool for initial assessment of HVFDs and a measure of CVI-related impairment, and needs further validation in a secondary independent sample.

Motion Processing Deficits in Children With Cerebral Visual Impairment and Good Visual Acuity

Purpose

We sought to characterize neural motion processing deficits in children with cerebral visual impairment (CVI) who have good visual acuity using an objective, quantifiable method (steady-state visual evoked potentials [SSVEPs]).

Methods

We recorded SSVEPs in response to three types of visual motion – absolute motion and more complex relative and rotary motion, comparing them to form-related vernier and contour responses. We studied a group of 31 children with CVI diagnosed via detailed clinical examinations and 28 age-matched healthy controls.

Results

Using measurements made at the appropriate response harmonics of the stimulation frequency, we found significant deficits in cerebral processing of relative and rotary motion but not of absolute motion in children with CVI compared with healthy controls. Vernier acuity, in keeping with good recognition acuity in both groups, was not different, nor were contour-related form responses.

Conclusions

Deficits for complex motion but relative sparing of elementary motion and form-related signals suggests preferential damage to extra-striate visual motion areas in children with CVI. The fact that these preferential losses occur in the absence of significant acuity loss indicates that they are not secondary to reduced visual acuity, but rather are an independent vulnerability in CVI. These results corroborate parental and caregivers’ reports of difficulties with tasks that involve motion perception in children with CVI.

Perceptual visual dysfunction in children - An Indian perspective

Perceptual visual dysfunction (PVD) comprises a group of vision disorders resulting from dysfunction of the posterior parietal and/or temporal lobes. Often, affected children have normal/near normal visual acuities and/or visual fields, but have difficulties in activities of daily living involving the use of vision. PVDs are known to be common among children with risk factors such as a history of prematurity and/or neurodevelopmental disorders. The inferior temporal lobes and ventral stream transform visual signals into perception, while the posterior parietal lobes and dorsal stream transform visual signals to non-consciously map the scene to guide action and facilitate attention. Dysfunction of these can lead to specific visual impairments that need to be identified during history taking, triggering ascertainment of further details by a structured inventory approach. Clinical tests to elicit dorsal and ventral stream visual dysfunctions have good specificity but low sensitivity. Neuropsychologists are rarely available in the developing world to perform detailed assessments, but there are a few tests that can be used by eye care professionals with some training. Optical coherence tomography (OCT) showing thinning of the ganglion cell layer and retinal nerve fiber layer is being explored as a potential tool for rapid assessment in the clinic. The behavioral outcomes of PVD can mimic psychological conditions including autism spectrum disorder, attention deficit hyperactivity disorder, specific learning disability, and intellectual impairment, and one needs to be aware of overlap among these differential diagnoses. A practical functional approach providing working solutions for each child's set of difficulties in day-to-day activities is needed.

Methods of visual assessment in children with cortical visual impairment

PURPOSE OF REVIEW

Cortical visual impairment (CVI) is the leading cause of pediatric visual impairment in developed countries. Currently, there is no standardized method of visual assessment in these children, who usually cannot participate in tests designed for typically developing children. A reproducible method of visual assessment that accurately reflects the multitude of visual deficits in CVI is critical to evaluate proposed therapies for this disorder. This review analyzes current research on methods of visual assessment in children with CVI.

RECENT FINDINGS

Earlier studies focused on measuring visual acuity in children with CVI. More recent studies have emphasized other aspects of visual function, such as contrast sensitivity, motion detection, and visual search. Current research topics include questionnaires, functional vision assessment (CVI Range), neuropsychological tests of visual perception, and eye tracking. Eye tracking shows promise for visual assessment in both clinical and research settings because it is objective and quantitative, with the ability to assess diverse visual parameters.

SUMMARY

Current research on visual assessment in children with CVI focuses on measuring deficits of visual function beyond visual acuity. This research represents an important step toward designing clinical trials to identify effective therapeutics for this increasingly prevalent disorder with heterogeneous manifestations.

Behavioural Features of Cerebral Visual Impairment Are Common in Children With Down Syndrome

It is widely recognised that children with Down syndrome have a broad range and a high prevalence of visual deficits and it has been suggested that those with Down syndrome are more likely to exhibit visual perception deficits indicative of cerebral visual impairment. This exploratory study aims to determine the prevalence of behavioural features suggestive of cerebral visual impairment (CVI) occurring with Down syndrome and whether the visual problems can be ascribed to optometric factors. A cohort of 226 families of children with Down syndrome (trisomy 21), aged 4–17, were invited to participate in a validated question inventory, to recognise visual perception issues. The clinical records of the participants were then reviewed retrospectively. A five-question screening instrument was used to indicate suspected CVI. The majority of the 81 families who responded to the questionnaire reported some level of visual perceptual difficulty in their child. Among this cohort, the prevalence of suspected CVI as indicated by the screening questionnaire was 38%. Only ametropia was found to have a significant association with suspected CVI, although this increased the correct prediction of suspected CVI outcome by only a small amount. Results suggest that children with Down syndrome are more likely to experience problems consistent with cerebral visual impairment, and that these may originate from a similar brain dysfunction to that which contributes to high levels of ametropia and failure to emmetropise. It is important that behavioural features of CVI are recognised in children with Down syndrome, further investigations initiated and appropriate management applied.

Cerebral visual impairment-related vision problems in primary school children: a cross-sectional survey

AIM

To estimate how many children in mainstream primary schools have cerebral visual impairment (CVI)-related vision problems and to investigate whether some indicators might be useful as red flags, if they were associated with increased risk for these problems.

METHOD

We conducted a survey of primary school children aged 5 to 11 years, using whether they were getting extra educational help and/or teacher- and parent-reported behaviour questionnaires to identify children at risk for CVI. These and a random 5% sample were assessed for CVI-related vision problems. We compared the usefulness of potential red flags using likelihood ratios.

RESULTS

We received questionnaires on 2298 mainstream-educated children and examined 248 children (152 [61%] males, 96 females [39%]; mean age 8y 1mo, SD 20mo, range 5y 6mo-11y 8mo). We identified 78 out of 248 children (31.5% of those examined, 3.4% of the total sample), who had at least one CVI-related vision problem. The majority (88%) were identified by one or more red flag but none were strongly predictive. Fewer than one in five children with any CVI-related vision problem had reduced visual acuity.

INTERPRETATION

Children with CVI-related vision problems were more prevalent than has been appreciated. Assessment of at-risk children may be useful so that opportunities to improve outcomes for children with CVI-related vision problems are not missed.

Visual Neuropsychology in Development: Anatomo-Functional Brain Mechanisms of Action/Perception Binding in Health and Disease

Vision is the main entrance for environmental input to the human brain. Even if vision is our most used sensory modality, its importance is not limited to environmental exploration. Rather it has strong links to motor competences, further extending to cognitive and social aspects of human life. These multifaceted relationships are particularly important in developmental age and become dramatically evident in presence of complex deficits originating from visual aberrancies. The present review summarizes the available neuropsychological evidence on the development of visual competences, with a particular focus on the associated visuo-motor integration skills in health and disease. With the aim of supporting future research and interventional settings, the goal of the present review is to constitute a solid base to help the translation of neuropsychological hypotheses into straightforward empirical investigations and rehabilitation/training protocols. This approach will further increase the impact, ameliorate the acceptance, and ease the use and implementation of lab-derived intervention protocols in real-life situations.

Improving outcomes for primary school children at risk of cerebral visual impairment (the CVI project): protocol of a feasibility study for a cluster-randomised controlled trial and health economic evaluation

INTRODUCTION

Cerebral visual impairment (CVI) refers to a spectrum of brain-related vision problems. CVI is associated with poor educational and mental health outcomes. An intervention has been developed to help children with CVI, involving input from clinicians, teachers and parents. The effectiveness of this intervention needs to be evaluated. This study aims to guide any refinements to the intervention or the design of a future cluster-randomised trial that may be needed.

METHODS AND ANALYSIS

This study will include all methods anticipated for a future cluster-randomised controlled trial. Eight primary schools will be recruited and randomised to receive the intervention or carry on with usual practice. The intervention will comprise an information pack for schools and access to a local paediatric ophthalmology clinic (who are prepared to assess them for CVI), for up to 5% of participating children. Outcome assessments will be carried out at baseline (before randomisation) and after 4-5 months of intervention period. Assessments will include children's self-reported quality of life, their learning ability and behaviour as reported by teachers, and family functioning reported by parents. Cost data will include service use, family expenditure on additional support (eg, private appointments and administration) and school spending and resource used in helping children with special educational needs or disability. A process evaluation (PE) will collect additional data relating to the implementation of the intervention and the trial processes, in the school and clinic settings. The protocol for the PE will be reported separately.

ETHICS AND DISSEMINATION

Ethical permission was obtained from the University of Bristol Faculty of Health Sciences Ethical Committee. The results will inform the design of a future trial to assess the effectiveness and cost-effectiveness of the intervention and will be shared with participants, CVI-support groups and peer-viewed journals.

TRIAL REGISTRATION NUMBER

ISRCTN13762177; Pre-results.

Measure of early vision use: initial validation with parents of children with cerebral palsy

PURPOSE

To report initial psychometric evidence on the Measure of Early Vision Use.

METHOD

Data on performance of the Measure of Early Vision Use scale were collected from 100 parents of children with cerebral palsy aged 0-12 years via online survey. Psychometric evaluation included assessment of scale dimensionality using Classical Test Theory and hypothesis testing for evidence of construct validity.

RESULTS

Principal components analysis of the 14-item parent-rated Measure of Early Vision Use revealed one component with an eigenvalue of 9.343, explaining 66.7% of variance; internal consistency was high (Cronbach's α = 0.96). Total scores ranged from 15-56 (Mean 42.8, standard deviation = 10.6). The results support seven pre-defined hypotheses including statistically significant differences in MEVU-total scores between children with and without parent-reported cerebral visual impairment.

CONCLUSIONS

Measure of Early Vision Use is the first assessment tool to describe 'how vision is used' in children with cerebral palsy. Results provide preliminary evidence that the measure comprises a unidimensional construct, sufficient construct validity, and feasibility as a parent-completed online assessment. Findings on internal structure provide foundational evidence and require further testing with Confirmatory Factor Analysis or Rasch Analysis.IMPLICATIONS FOR REHABILITATIONThe Measure of Early Vision Use is a new instrument to describe the use of basic visual abilities and is feasible to use as a parent-completed online questionnaire.The Measure of Early Vision Use is a unidimensional scale with sufficient construct validity to supports its use as a measure of 'how vision is used' without confounding visual ability with the reason why it might be impaired (e.g., cerebral vision impairment, motor limitations, or cognition).There is potential for the Measure of Early Vision Use to support early intervention planning for children with (or at high risk of) cerebral palsy.

Development of the Parental Questionnaire for Cerebral Visual Impairment in Children Younger than 72 Months

Background and Purpose

Cerebral visual impairment (CVI) is an underdiagnosed condition in children, and its assessment tools have focused on older children. We aimed to develop a parental questionnaire for cerebral visual impairment (PQCVI) for screening CVI in young children.

Methods

The PQCVI comprised 23 questions based on a modified version of Houliston and Dutton's questionnaire for older children. The PQCVI with neurocognitive function tests was applied to 201 child-parent pairs with typically developing children younger than 72 months (age 32.4±20.1 months, mean±standard deviation). The children were classified into six age groups. The normative data, cutoff scores, and internal reliability were assessed and item analysis was performed. We referred to the total score for all questions as the cerebral visual function (CVF) score.

Results

The normative data showed that the CVF score and the scores corresponding to ventral-stream and dorsal-stream visual functions plausibly increased with age. The scores rapidly reached 90% of their maximum values up to the age of 36 months, after which they increased slowly. Cronbach's alpha for all questions across all age groups was 0.97, showing excellent consistency. The item difficulty and item discrimination coefficients showed that the questions were generally adequate for this age stage.

Conclusions

The PQCVI items produced reliable responses in children younger than 72 months. The rapid increase in scores before the age of 3 years supports the importance of early identification of CVI. Following additional clinical verification, the PQCVI may be useful for CVI screening.

Visuoperceptual profiles of children using the Flemish cerebral visual impairment questionnaire

AIM

To investigate the underlying factor structure of the 46-item Flemish cerebral visual impairment (CVI) questionnaire, differentiate the factor scores of children with and without CVI, and examine the impact of comorbidities on factor scores.

METHOD

The records of 630 children (386 males, 244 females; median age 77mo; interquartile range 63-98mo) who visited the CVI clinic and the Centre for Developmental Disabilities at the University Hospitals of Leuven from 2001 to 2018 were reviewed systematically. Inclusion criteria included an up-to-date questionnaire, a definitive diagnosis, and clinical assessment.

RESULTS

Three hundred and forty-five children (179 with CVI [108 males, 71 females; median age 74mo; interquartile range 61-93mo] and 166 without CVI [110 males, 56 females; median age 88mo; interquartile range 70-107mo]) were included. An exploratory factor analysis resulted in a 5-factor (object and face processing impairments; visual (dis)interest; clutter and distance viewing impairments; moving in space impairments; and anxiety-related behaviours) biologically and clinically plausible model, which retained 35 items and explained 56% of the total variance. Mann-Whitney U tests indicated that factors 1 to 4 were significantly higher in children with CVI compared to children without CVI (p-values ranged from p<0.001 to p<0.05; effect sizes ranged from 0.11 to 0.33); factor 5 showed no differences. Autism, developmental coordination disorder, epilepsy, and cerebral palsy impacted factor scores.

INTERPRETATION

A 5-factor structure of the Flemish CVI questionnaire differentiates children with and without CVI. Comorbidities should be accounted for when researching CVI.

WHAT THIS PAPER ADDS

Cerebral visual impairment (CVI) is characterized by impaired object and face processing and impaired visual interest. CVI is also characterized by impaired clutter and distance viewing, and impaired moving in space. All children (with or without CVI) demonstrated anxiety-related behaviours. Autism affected object/face processing, whereas developmental coordination disorder, epilepsy, and cerebral palsy affected visual interest.