Neonatal Assessment Visual European Grid (NAVEG): Unveiling neurological risk

Spectrum of Visual Dysfunction Detected by a Novel Testing Protocol Within a Special School Eye Care Service

Introduction

Children with special educational needs are more likely to have vision problems than peers in mainstream education. Reports focus on visual acuity and refraction, overlooking visuoperceptual difficulties, including cerebral visual impairment. This article reports on the feasibility and outcomes of visual function testing performed during in-school visual assessments.

Method

A retrospective chart review was undertaken of children participating in a special school vision programme. The testing strategy included acuity, fields, contrast sensitivity, eye movements, accommodation, stereopsis, visual attention, refraction and a parent-completed questionnaire. The testing method was chosen based on the child's ability to engage with testing.

Results

78 cases were identified (mean age 9.6 years). Low vision (worse than 6/19) was identified in 31%. All six tests of visual function were completed by 44% (mean 5.1; range 2-6). The mean number of atypical responses was 1 (range 0-4). Almost half (49%) showed at least one atypical response, most commonly visual attention (35%) and 25% had atypical eye movements.

Discussion

Overall, only 20% of children in the special school setting demonstrated a normal response to each test they were able to complete. Acuity testing alone does not demonstrate the atypical visual function of a child with special needs. Using techniques which require minimal cognitive, speech or motor function, a range of visual functions can be elicited during in-school testing. This testing strategy has the advantage of demonstrating areas of visual (dys)function impacting on the child's ability to access learning which can be immediately fed back to teaching staff and carers.

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.

Visual Behaviours (ViBes) in Cerebral Visual Impairment: Validating a Descriptive Tool to Support Diagnosis and Monitoring

Introduction

Cerebral visual impairment (CVI) is the most common cause of visual impairment in children in the UK. Diagnosis is based on identification of visual behaviours (ViBes) relating to visual dysfunction. Examination techniques and inventories have been developed to elicit these in children with a developmental age of two years or more. The absence of a structured approach to recording visual behaviours in children with complex needs is a barrier to diagnosis. The aim of the study was to develop a matrix of visual behaviours seen in pre-verbal and pre-motor children with visual impairment and establish its content validity and inter-rater reliability.

Methods

ViBe content validation:: Visual behaviour descriptors relating to visual function were collated and categorised by expert consensus of vision professionals into a matrix composed of three functions (attention, field/fixation, motor response) and five levels (0 = no awareness; 1 = visual awareness; 2 = visual attention; 3 = visual detection; 4 = visual understanding).ViBe inter-rater reliability:: The participants (two orthoptists, an optometrist, an ophthalmologist and two qualified teachers of the visually impaired) used the ViBe matrix to independently score each of 17 short video clips of children demonstrating visual behaviours seen in CVI.

Results

The ViBe matrix will be presented. Cohen's kappa for the matrix was 0.67, demonstrating moderate-to-strong inter-rater reliability.

Conclusion

The development of standardised descriptors can support clinicians and teachers in identifying areas of concern for children with complex needs. In addition, the ViBe matrix could be utilised in research, clinical and diagnostic reports to clearly communicate the areas of visual dysfunction and track progress resulting from interventions.

Key Points

The absence of a structured approach to recording visual behaviours in children with complex needs is a barrier to diagnosis.The ViBe matrix offers descriptors relating to visual behaviours and has demonstrated acceptable inter-rater reliability.The tool may support the identification and diagnosis of cerebral visual impairment in a population of children who cannot access standard testing.

Visual Function Score: A New Clinical Tool to Assess Visual Function and Detect Visual Disorders in Children

INTRODUCTION

A comprehensive assessment of visual functioning at an early age is important not only for identifying and defining visual impairment but also for planning personalized rehabilitation programs based on the visual diagnosis. Since existing tools to evaluate visual functioning present some important limitations (e.g., they are based on qualitative reports, they do not take into account environmental adaptations of visual testing or they have not been formally validated as clinical instruments), the present work has the main aim to propose a new clinical tool (Visual Function Score, VFS) to detect and define visual disorders at an early age.

METHODS

The Visual Function Score was administered to one hundred visually impaired children (age range 4 months to 17.75 years old) in the form of a professional-reported protocol for a total of 51 items, each of which is assigned a score from 1 to 9 (or from 0 to 9 in some specific cases). The VFS produces three sub-scores and a global score (from 0 to 100), resulting in a quantitative evaluation of visual functioning.

RESULTS

The VFS can detect the well-known differences between different types of visual impairment (cerebral, oculomotor, and peripheral or grouped as central and peripheral) and takes into account different environments in the definition of a quantitative score of visual functioning.

DISCUSSION

Overall, the use of a quantitative tool to evaluate visual functions and functional vision such as the VFS would be fundamental to monitor the progresses of patients over time in response to rehabilitation interventions.

An office-based fix-and-follow grading system assessing visual function in preverbal children

Background

Assessing visual function in infants is usually challenging. Fix-and-Follow is a simple and popular method for assessing early development of visual perception in infants, currently however, there is no formal reproducible method for grading the capacity of fix-and-follow. This study was to develop and validate a new fix-and-follow grading system for assessing visual function development in preverbal children.

Methods

In this cross-sectional study, the fix-and-follow grades was evaluated in 21 consecutive preverbal children. Fixation was categorised as grade 1 if there was no response to the target and grade 2 if there was a response but only for < 3 s. Grades of 3 and 4 were assigned based capacities to (1) fix on a moving target for ≥3 s, and (2) shift fixation from one target to another. If only one of these two criteria was met, grade 3 was assigned. If both were met, grade 4 was assigned. Following was evaluated using smooth pursuit movement, where grade 1 indicated no movement, grade 2 partial movement, and grade 3 complete movement. Two ophthalmologists independently applied the grading method in all patients. Then one of two examiners repeated the examinations to investigate the intra-observer agreement of the grading system.

Results

Intra-observer agreement was excellent (Kappa coefficient = 0.823) and inter-observer agreement was good (Kappa coefficient = 0.625). All patients who exhibited abnormal ocular movement had score discrepancy between a new fix-and-following grading examination.

Conclusions

The new fix-and-follow grading scale can be applied easily in preverbal children in an office setting, and it proved reliable and reproducible.

Cortical Visual Impairments and Learning Disabilities

Medical advances in neonatology have improved the survival rate of premature infants, as well as children who are born under difficult neurological conditions. As a result, the prevalence of cerebral dysfunctions, whether minimal or more severe, is increasing in all industrialized countries and in some developing nations. Whereas in the past, ophthalmological diseases were considered principally responsible for severe visual impairment, today, all recent epidemiological studies show that the primary cause of blindness and severe visual impairment in children in industrialized countries is now neurological, with lesions acquired around the time of birth currently comprising the commonest contributor. The resulting cortical or cerebral visual impairments (CVIs) have long been ignored, or have been confused either with other ophthalmological disorders causing low vision, or with a range of learning disabilities. We present here the deleterious consequences that CVI can have upon learning and social interaction, and how these can be given behavioral labels without the underlying visual causes being considered. We discuss the need to train and inform clinicians in the identification and diagnosis of CVI, and how to distinguish the diagnosis of CVI from amongst other visual disorders, including the specific learning disorders. This is important because the range of approaches needed to enhance the development of children with CVI is specific to each child's unique visual needs, making incorrect labeling or diagnosis potentially detrimental to affected children because these needs are not met.

Cerebral Visual Impairment in CDKL5 Deficiency Disorder Correlates With Developmental Achievement

Cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder is a rare neurodevelopmental disorder characterized by infantile-onset refractory epilepsy, profound developmental delays, and cerebral visual impairment. Although there is evidence that the presence of cerebral visual impairment in CDKL5 deficiency disorder is common, the potential impact of cerebral visual impairment severity on developmental attainment has not been explored directly. Focusing on a cohort of 46 children with CDKL5 deficiency disorder, examination features indicative of cerebral visual impairment were quantified and compared to developmental achievement. The derived cerebral visual impairment severity score was inversely correlated with developmental attainment, bolstering the supposition that cerebral visual impairment severity may provide a useful early biomarker of disease severity and prognosis. This study demonstrates the utility of a cerebral visual impairment score to better capture the range of cerebral visual impairment severity in the CDKL5 deficiency disorder population and further elucidates the interaction between cerebral visual impairment and developmental outcomes.

Oral melatonin as a new tool for neuroprotection in preterm newborns: study protocol for a randomized controlled trial

Background

Prevention of neurodevelopmental impairment due to preterm birth is a major health challenge. Despite advanced obstetric and neonatal care, to date there are few neuroprotective molecules available. Melatonin has been shown to have anti-oxidant/anti-inflammatory effects and to reduce brain damage, mainly after hypoxic ischemic encephalopathy. The planned study will be the first aiming to evaluate the capacity of melatonin to mitigate brain impairment due to premature birth.

Method

In our planned prospective, multicenter, double-blind, randomized vs placebo study, we will recruit, within 96 h of birth, 60 preterm newborns with a gestational age ≤ 29 weeks + 6 days; these infants will be randomly allocated to oral melatonin, 3 mg/kg/day, or placebo for 15 days. After the administration period, we will measure plasma levels of malondialdehyde, a lipid peroxidation product considered an early biological marker of melatonin treatment efficacy (primary outcome). At term-equivalent age, we will evaluate neurological status (through cerebral ultrasound, cerebral magnetic resonance imaging, vision and hearing evaluations, clinical neurological assessment, and screening for retinopathy of prematurity) as well as the incidence of bronchodysplasia and sepsis. We will also monitor neurodevelopmental outcome during the first 24 months of corrected age (using the modified Fagan Test of Infant Intelligence at 4–6 months and standardized neurological and developmental assessments at 24 months).

Discussion

Preterm birth survivors often present long-term neurodevelopmental sequelae, such as motor, learning, social-behavioral, and communication problems. We aim to assess the role of melatonin as a neuroprotectant during the first weeks of extrauterine life, when preterm infants are unable to produce it spontaneously. This approach is based on the supposition that its anti-oxidant mechanism could be useful in preventing neurodevelopmental impairment. Considering the short- and long-term morbidities related to preterm birth, and the financial and social costs of the care of preterm infants, both at birth and over time, we suggest that melatonin administration could lead to considerable saving of resources. This would be the first study addressing the role of melatonin in very low birth weight preterm newborns, and it could provide a basis for further studies on melatonin as a neuroprotection strategy in this vulnerable population.

Trial registration

ClinicalTrials.gov NCT04235673. Prospectively registered on 22 January 2020.

Assessment tool for visual perception deficits in cerebral visual impairment: development and normative data of typically developing children

AIM

To develop an assessment tool that measures a wide range of visual perceptual deficits common in cerebral visual impairment (CVI) and to provide normative data from typically developing children between 3 and 6 years of age.

METHOD

Test development reflected cross-talk between vision research and clinical relevance for CVI. The Children's Visual Impairment Test for 3- to 6-year-olds (CVIT 3-6) includes 14 subtests covering four domains of visual perception: Object Recognition, Degraded Object Recognition, Motion Perception, and Global-Local Processing. Normative data were collected from 301 typically developing children (mean age 4y 8mo [SD 9.7mo]; 148 females, 153 males). A questionnaire was administered to parents about pregnancy duration, birth, and developmental problems.

RESULTS

Average total CVIT 3-6 performance was 60.1 (SD 5.5) out of 70. The cut-off score for normal visual perception (53) was set at the 10th centile of scores in typically developing children. Multiple regression indicated CVIT 3-6 visual perception scores increase with age for children born at 36 weeks' gestational age or later (β=-18.03, 95% confidence interval -31.31 to -4.75).

INTERPRETATION

CVIT 3-6 is a tool to assess a wide range of visual perceptual deficits common in CVI. Age-dependent normative data are available because we found performance increased with age.

WHAT THE PAPER ADDS

A test for visual perceptual deficits common in cerebral visual impairment. Visual perceptual functions improve with age in full-term typically developing children.

Cerebral Visual Impairment and Clinical Assessment: The European Perspective

This paper summarizes the multidisciplinary pediatric assessment methods of 3 European centers for identifying and assessing cerebral visual impairment in childhood. It describes a comprehensive neurodevelopmental assessment evaluation in which visual aspects play an important part. Developmental trajectories and the heterogeneity of the clinical picture are emphasized. Multidisciplinary ophthalmology and neurodisability/neurology teamwork together with the parent and teachers, to reach an integrated and individualized perspective for the individual child, are described. This comprehensive assessment is the starting point for habilitation programs and interventions, that can support and meet the child's needs and help them reach their optimal potential. Future developments in classification of the cerebral visual impairment conditions, building on the child's individual assessment profile, will further enhance the direction of clinical, educational, and research progress.

CDKL5 deficiency disorder: Relationship between genotype, epilepsy, cortical visual impairment, and development

OBJECTIVE

The cyclin-dependent kinase like 5 (CDKL5) gene is a known cause of early onset developmental and epileptic encephalopathy, also known as CDKL5 deficiency disorder (CDD). We sought to (1) provide a description of seizure types in patients with CDD, (2) provide an assessment of the frequency of seizure-free periods and cortical visual impairment (CVI), (3) correlate these features with genotype and gender, and (4) correlate these features with developmental milestones.

METHODS

This is a cohort study of patients with CDD. Phenotypic features were explored and correlated with gene variant grouping and gender. A developmental score was created based on achieving seven primary milestones. Phenotypic variables were correlated with the developmental score to explore markers of better developmental outcomes. Multivariate linear regression was used to account for age at last visit.

RESULTS

Ninety-two patients with CDD were seen during the enrollment period. Eighteen were male (19%); median age at last visit was 5 years (interquartile range = 2.0-11.0). Eighty-one percent of patients developed epileptic spasms, but only 47% of those also had hypsarrhythmia. Previously described hypermotor-tonic-spasms sequence was seen in only 24% of patients, but 56% of patients had seizures with multiple phases (often tonic and spasms). Forty-three percent of patients experienced a seizure-free period ranging from 1 to >12 months, but only 6% were still seizure-free at the last visit. CVI was present in 75% of all CDD patients. None of these features was associated with genotype group or gender. CVI was correlated with reduced milestone achievement after adjusting for age at last visit and a history of hypsarrhythmia.

SIGNIFICANCE

The most common seizure types in CDD are epileptic spasms (often without hypsarrhythmia) and tonic seizures that may cluster together. CVI is a common feature in CDD and is correlated with achieving fewer milestones.