Neuro-ophthalmological disorders in cerebral palsy: ophthalmological, oculomotor, and visual aspects

Motor-Based Application Process for Cerebral Visual Impairment-Related Questionnaires for School-Age Children with Cerebral Palsy

This study aims to examine the psychometric properties of questionnaires related to cerebral visual impairment (CVI) in school-age children with cerebral palsy (CP). Additionally, it proposes an application process based on motor functionality for occupational therapists. A total of 288 children with CP were recruited for the study and administered the CVI Motor Questionnaire (CVI-MQ). The children's daily visual performance was assessed using the CVI Inventory and the Functional Vision Questionnaire (FVQ) considering the children's ambulatory status. The FVQ and the two factors extracted from the CVI Inventory significantly predicted visual functioning. Specific questionnaires related to CVI, applied with gross motor function in mind, can be valuable tools for occupational therapists to assess daily visual performance.

Visual, perceptual functions, and functional vision in children with unilateral cerebral palsy compared to children with neurotypical development

AIM

To investigate visual (perceptual) function and functional vision in children with unilateral cerebral palsy (CP) and children with neurotypical development (NTD).

METHOD

Fifty children with unilateral CP (mean age 11 years 11 months, SD 2 years 10 months, range 7-15 years; 27 males; 26 left-sided unilateral CP; Manual Ability Classification System [MACS] levels: I, 27; II, 16; III, 7) and 50 age- and sex-matched children with NTD participated in a cross-sectional study. Visual acuity, stereoacuity, and visual-perceptual functions were measured with standardized clinical tests. Functional vision was assessed in children with unilateral CP with the Flemish cerebral visual impairment questionnaire (FCVIQ). Group differences were investigated with Mann-Whitney U tests, Kruskal-Wallis tests, and the relative effect sizes r, η2 respectively. Correlations between visual assessments and the FCVIQ were investigated with Spearman's rank correlations.

RESULTS

The total group of children with unilateral CP showed reduced visual acuity compared with children with NTD (p = 0.02, r = 0.23). Only children with left-sided unilateral CP scored lower than those with NTD on stereoacuity (p < 0.01, r = 0.36). Children with right/left-sided unilateral CP scored significantly lower than those with NTD on visual-perceptual functions (p = 0.001-0.02), with large effect sizes on visuomotor integration and visual closure (both r = 0.57). Children with unilateral CP classified in MACS level III showed significantly lower scores on visual-perceptual assessments than children classified in MACS level I. Stereoacuity and visual-perceptual functions negatively correlated with the FCVIQ, with the highest association with visual (dis)interest and anxiety-related behaviours.

INTERPRETATION

Multi-level visual profiling is warranted in the clinical intake of children with unilateral CP to detect visual impairments that further compromise their level of functioning.

Eyes on CVI: Eye movements unveil distinct visual search patterns in Cerebral Visual Impairment compared to ADHD, dyslexia, and neurotypical children

Visual search problems are often reported in children with Cerebral Visual Impairment (CVI). To tackle the clinical challenge of objectively differentiating CVI from other neurodevelopmental disorders, we developed a novel test battery. Visual search tasks were coupled with verbal and gaze-based measurements. Two search tasks were performed by children with CVI (n: 22; mean age (SD): 9.63 (.46) years) ADHD (n: 32; mean age (SD): 10.51 (.25) years), dyslexia (n: 28; mean age (SD): 10.29 (.20) years) and neurotypical development (n: 44; mean age (SD): 9.30 (.30) years). Children with CVI had more impaired search performance compared to all other groups, especially in crowded and unstructured displays and even when they had normal visual acuity. In-depth gaze-based analyses revealed that this group searched in overall larger areas and needed more time to recognize a target, particularly after their initial fixation on the target. Our gaze-based approach to visual search offers new insights into the distinct search patterns and behaviours of children with CVI. Their tendency to overlook targets whilst fixating on it, point towards higher-order visual function (HOVF) deficits. The novel method is feasible, valid, and promising for clinical differential-diagnostic evaluation between CVI, ADHD and dyslexia, and for informing individualized training.

Academic skills in children with cerebral palsy and specific learning disorders

AIM

To investigate the prevalence and clinical manifestations of reading, writing, and mathematics disorders in children with cerebral palsy (CP). We explored how the clinical profile of these children differed from those with specific learning disorders (SLDs), taking into account several factors, particularly IQ scores, neuropsychological aspects, and the presence of a visual impairment.

METHOD

A prospective cross-sectional study was conducted in 42 children with CP (mean age 9 years 8 months; SD = 2 years 2 months) and 60 children with SLDs (mean age 10 years; SD = 1 year 7 months). Clinical characteristics, neuromotor and cognitive profiles, neuropsychological aspects (speech performance, academic skills, visual attention, phonological awareness, working memory), and signs of visual impairment (visual acuity, contrast sensitivity, visual field, oculomotor functions) were assessed. A machine learning approach consisting of a random forest algorithm, where the outcome was the diagnosis and the covariates were the clinical variables collected in the sample, was used for the analyses.

RESULTS

About 59% of the children with CP had reading, writing, or mathematics disorders. Children with CP with learning disorders had a low performance IQ, normal phonological awareness, and working memory difficulties, whereas children with SLDs had normal performance IQ, impaired phonological awareness, and mild working memory difficulties. There were no differences in verbal IQ between the two groups.

INTERPRETATION

Learning disorders are frequently associated with CP, with different clinical characteristics, compared with SLDs. Assessment of academic skills is mandatory in these children, even if the IQ is normal. At school age, specific interventions to promote academic skills in children with CP could be a major rehabilitative goal.

WHAT THIS PAPER ADDS

Reading, writing, and mathematics disorders in cerebral palsy have specific clinical characteristics. Their underlying mechanisms differ from those described in specific learning disorders. Working memory impairment can be considered a hallmark of learning disorders in children with cerebral palsy.

Prevalence and Types of Strabismus in Cerebral Palsy: A Global and Historical Perspective Based on a Systematic Review and Meta-Analysis

PURPOSE

Strabismus is more frequent in cerebral palsy (CP) than in the normal population, but reports differ how much it is increased. We here examined the global prevalence and types of strabismus in CP, whether esotropia or exotropia is more frequent, and whether the prevalence differs between ethnicities and/or country income levels, and between generations.

METHODS

We compiled in a systematic review and meta-analysis the results of 147 CP studies that report the prevalence of strabismus or the ratio of esotropia to exotropia, and we conducted subgroup analyses for region (income level) and ethnicity. We performed a pooled analysis for the CP strabismus prevalence, and estimated the global number of CP cases with strabismus.

RESULTS

The pooled prevalence of strabismus in CP is 49.8% in high-income countries and 39.8% in lower-income countries. We estimate the global number of strabismus cases in CP as 12.2 million, with 7.6 million males and 4.6 million females, based on current estimates of 29.6 million global CP cases. Esotropia is more frequent than exotropia in Caucasians, while exotropia is more frequent than esotropia in Hispanic and in some Asian and African populations. The strabismus prevalence in CP increases with increasing country income levels.

CONCLUSION

Generational changes in strabismus prevalence appear to reflect a transition of CP types and an increase in prevalence as countries attain higher income and more effective maternal health care. The distribution of esotropia and exotropia in CP patients largely reflects the horizontal strabismus type that is predominant in the subject's ethnicity.

The relation between neuroimaging and visual impairment in children and adolescents with cerebral palsy: A systematic review

OBJECTIVE

The structure-function relation between magnetic resonance imaging (MRI) and visual impairment (VI) in children with cerebral palsy (CP) has not been fully unravelled. The present systematic review aims to summarize the relation between brain lesions on MRI and VI in children and adolescents with CP.

METHODS

PubMed, Embase, Web of Science Core Collection, and Cochrane Database were systematically searched according to the PRISMA checklist. A total of 45 articles met the inclusion criteria.

RESULTS

White matter lesions were most frequently associated with VI. Only 25 studies described lesions within specific structures, mainly in the optic radiations. Only four studies reported on the thalamus. 8.4% of children with CP showed no brain abnormalities on MRI. Diffusion-weighted MRI studies showed that decreased structural connectivity in the optic radiations, superior longitudinal fasciculus, posterior limb of the internal capsule, and occipital lobe is associated with more severe VI.

CONCLUSIONS

All types of brain lesions lead to visual dysfunctions, arguing for a comprehensive visual assessment in all children with CP. Whereas white matter damage is a well-known contributor, the exact contribution of specific visual structures requires further investigation, to enable early prediction, detection, and intervention.

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.

Signs of perceptual disorder during movement were reliably assessed in children with cerebral palsy in Sweden

AIM

The aim of this Swedish study was to evaluate the assessment of clinical signs of perceptual disorder in children with cerebral palsy (CP).

METHODS

Three experienced raters assessed 56 videos of 19 children from 1 to 18 years of age with bilateral spastic CP, which were recorded by colleagues at an Italian hospital. Six signs were evaluated for inter-rater reliability and criterion validity. Clinical applicability was evaluated by assessing inter-rater reliability between 47 Swedish clinicians, who examined 15 of the videos during face-to-face and online education seminars. There were 41 physiotherapists, two occupational therapists and four doctors, with 1-37 years of clinical experience and a median of 10 years.

RESULTS

The experienced raters demonstrated moderate to almost perfect inter-rater reliability (kappa 0.54-0.81) and criterion validity (0.54-0.87) for startle reaction, upper limbs in startle position, averted eye gaze and eye blinking. The clinicians recognised these signs with at least moderate reliability (0.56-0.88). Grimacing and posture freezing were less reliable (0.22-0.35) and valid (0.09-0.50).

CONCLUSION

Four of the six signs of perceptual disorder were reliably recognised by experienced raters and by clinicians after education seminars. Extended education and larger study samples are needed to recognise all the signs.

Prevalence and types of strabismus in cerebral palsy: A global and historical perspective based on a systematic review and meta-analysis

Purpose

Strabismus is more frequent in cerebral palsy (CP) than in the normal population, but reports differ how much it is increased. We here examined the global prevalence and types of strabismus in CP, whether esotropia or exotropia is more frequent, and whether the prevalence differs between ethnicities and/or country income levels, and between generations.

Methods

We compiled in a systematic review and meta-analysis the results of 147 CP studies that report the prevalence of strabismus or the ratio of esotropia to exotropia, and we conducted subgroup analyses for region (income level) and ethnicity. We performed a pooled analysis for the CP strabismus prevalence, and estimated the global number of CP cases with strabismus.

Results

The pooled prevalence of strabismus in CP is 49.8% in high-income countries and 39.8% in lower-income countries. We estimate the global number of strabismus cases in CP as 12.2 million, with 7.6 million males and 4.6 million females, based on current estimates of 29.6 million global CP cases. Esotropia is more frequent than exotropia in Caucasians, while exotropia is more frequent than esotropia in Hispanic and in some Asian and African populations. The strabismus prevalence in CP increases with increasing country income levels.

Conclusion

Generational changes in strabismus prevalence appear to reflect a transition of CP types and an increase in prevalence as countries attain higher income and more effective maternal health care. The distribution of esotropia and exotropia in CP patients largely reflects the horizontal strabismus type that is predominant in the subject's ethnicity.

Biological and environmental factors may affect children's executive function through motor and sensorimotor development: Preterm birth and cerebral palsy

Disruptive biological and environmental factors may undermine the development of children's motor and sensorimotor skills. Since the development of cognitive skills, including executive function, is grounded in early motor and sensorimotor experiences, early delays or impairments in motor and sensorimotor processing often trigger dynamic developmental cascades that lead to suboptimal executive function outcomes. The purpose of this perspective paper is to link early differences in motor/sensorimotor processing to the development of executive function in children born preterm or with cerebral palsy. Uncovering such links in clinical populations would improve our understanding of developmental pathways and key motor and sensorimotor skills that are antecedent and foundational for the development of executive function. This knowledge will allow the refinement of early interventions targeting motor and sensorimotor skills with the goal of proactively improving executive function outcomes in at-risk populations.

Neurovisual profile in children affected by Angelman syndrome

BACKGROUND

Angelman syndrome (AS) is a rare neurogenetic disorder caused by altered expression of the maternal copy of the UBE3A gene. Together with motor, cognitive, and speech impairment, ophthalmological findings including strabismus, and ocular fundus hypopigmentation characterize the clinical phenotype. The aim of this study was to detail the neurovisual profile of children affected by AS and to explore any possible genotype-phenotype correlations.

METHODS

Thirty-seven children (23 females, mean age 102.8 ± 54.4 months, age range 22 to 251 months) with molecular confirmed diagnosis of AS were enrolled in the study. All underwent a comprehensive video-recorded neurovisual evaluation including the assessment of ophthalmological aspects, oculomotor functions, and basic visual abilities.

RESULTS

All children had visual impairments mainly characterized by refractive errors, ocular fundus changes, strabismus, discontinuous/jerky smooth pursuit and altered saccadic movements, and/or reduced visual acuity. Comparing the neurovisual profiles between the deletion and non-deletion genetic subgroups, we found a significant statistical correlation between genotype and ocular fundus hypopigmentation (p = 0.03), discontinuous smooth pursuit (p < 0.05), and contrast sensitivity abnormalities (p < 0.01) being more frequent in the deletion subgroup.

CONCLUSIONS

Subjects affected by AS present a wide spectrum of neurovisual impairments that lead to a clinical profile consistent with cerebral visual impairment (CVI). Moreover, subjects with a chromosome deletion show a more severe visual phenotype with respect to ocular fundus changes, smooth pursuit movements, and contrast sensitivity. Early detection of these impaired visual functions may help promote the introduction of neurovisual habilitative programs which can improve children's visual, neuromotor, and cognitive outcomes.

Providing a Primary Care Medical Home for Children and Youth With Cerebral Palsy

Cerebral palsy (CP) is the most common motor disorder of childhood, with prevalence estimates ranging from 1.5 to 4 in 1000 live births. This clinical report seeks to provide primary care physicians with guidance to detect children with CP; collaborate with specialists in treating the patient; manage associated medical, developmental, and behavioral problems; and provide general medical care to their patients with CP.

Exploration of multimodal alternative access for individuals with severe motor impairments: Proof of concept

Many individuals with complex communication needs and severe motor impairments are unable to control technologies through conventional means and require alternative access techniques to achieve accurate and efficient access. With current alternative access techniques, individuals with severe motor impairments are limited in that they can only use one access technique at a time. The purpose of this project was to test proof of concept of a new multimodal access technique which integrated eye gaze and single switch scanning selection techniques. The aims were to investigate the learning patterns of two adults with severe cerebral palsy when first introduced to the multimodal access technique and then to compare the accuracy and efficiency of multimodal to single-modality access when selecting targets on an AAC visual scene display. The participants learned to use the multimodal access technique; they demonstrated improvements in their accuracy of selection across sessions and attained at least 80% accuracy within 3-15 training sessions. Both participants achieved similar accuracy with multimodal access compared to single-modality, but took longer to select targets with multimodal access compared to single-modality. The potential utility of multimodal access is explored as well as important avenues for future research.

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.

Surgical outcomes and observation in exotropia cerebral palsy children with cortical visual impairment

PURPOSE

Cortical visual impairment (CVI) is the common cause of pediatric visual impairment in cerebral palsy (CP) while exotropia is the most common strabismus associated with CP. We aim to observe the strabismic surgery outcomes in pediatric patients with CP and CVI.

METHOD

Our medical records were collected from pediatric patients treated in our hospital from May 1, 2017 to Jan 1, 2022. With normal intelligence assessment and diagnosis of exotropia in children with CP and CVI, microsurgeries were performed under intravenous combined inhalation anesthesia. The strabismus was examined by the prism test under best vision correction and the contrast sensitivity testing (CST) was measured at five levels of spatial frequencies.

RESULT

A total of 38 exotropia patients with CP and CVI were identified and included for analysis during the study period with age ranged from 5 to 12 years (mean 8.45 years) and mean follow up duration was 8.7 months (6-42 months). After bilateral lateral rectus recession (with/without medial rectus resection or inferior oblique transposition), the exotropia amount of participants were obviously revealed from - 30 ~ - 140 (median, IQR: - 50, 40) prism diopters (PD) preoperatively to 0 ~ - 15 (0, 5) PD postoperatively. Statistically significantly improvements were observed at all levels of spatial frequency on CST postoperatively, especially at high spatial frequency areas (p < 0.05).

CONCLUSION

Our results demonstrated that the effect of strabismus surgery on exotropia in children with CP and CVI were stable and monocular contrast sensitivity post- operation increased significantly at all spatial frequencies levels.

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.

Altered spontaneous cortical activity predicts pain perception in individuals with cerebral palsy

Cerebral palsy is the most common paediatric neurological disorder and results in extensive impairment to the sensorimotor system. However, these individuals also experience increased pain perception, resulting in decreased quality of life. In the present study, we utilized magnetoencephalographic brain imaging to examine whether alterations in spontaneous neural activity predict the level of pain experienced in a cohort of 38 individuals with spastic diplegic cerebral palsy and 67 neurotypical controls. Participants completed 5 min of an eyes closed resting-state paradigm while undergoing a magnetoencephalography recording. The magnetoencephalographic data were then source imaged, and the power within the delta (2–4 Hz), theta (5–7 Hz), alpha (8–12 Hz), beta (15–29 Hz), low gamma (30–59 Hz) and high gamma (60–90 Hz) frequency bands were computed. The resulting power spectral density maps were analysed vertex-wise to identify differences in spontaneous activity between groups. Our findings indicated that spontaneous cortical activity was altered in the participants with cerebral palsy in the delta, alpha, beta, low gamma and high gamma bands across the occipital, frontal and secondary somatosensory cortical areas (all p_FWE < 0.05). Furthermore, we also found that the altered beta band spontaneous activity in the secondary somatosensory cortices predicted heightened pain perception in the individuals with cerebral palsy (P = 0.039). Overall, these results demonstrate that spontaneous cortical activity within individuals with cerebral palsy is altered in comparison to their neurotypical peers and may predict increased pain perception in this patient population. Potentially, changes in spontaneous resting-state activity may be utilized to measure the effectiveness of current treatment approaches that are directed at reducing the pain experienced by individuals with cerebral palsy.

Age-Related Effects on the Spectrum of Cerebral Visual Impairment in Children With Cerebral Palsy

Background

Cerebral Visual Impairment (CVI) is a very common finding in children affected by Cerebral Palsy (CP). In this paper we studied the characteristics of CVI of a large group of children with CP and CVI, describing their neurovisual profiles according to three different age subgroups (subgroup 1: infants 6 months–2 years; subgroup 2: pre-school age 3–5 years; subgroup 3: school age ≥ 6 years).

Methods

We enrolled 180 subjects (104 males, mean age 66 ± 42.6 months; range 6–192 months) with CP and CVI for the study. We carried out a demographic and clinical data collection, neurological examination, developmental or cognitive assessment, and a video-recorded visual function assessment including an evaluation of ophthalmological characteristics, oculomotor functions, and basic visual functions. In school-aged children, we also performed an evaluation of their cognitive-visual profiles.

Results

There were signs of CVI in all the three subgroups. Subgroup 1 (62 children) and subgroup 2 (50 children) were different for fixation (p = 0.02), visual acuity (p = 0.03) and contrast sensitivity (p < 0.01), being more frequently impaired in younger children. Comparing subgroup 2 with subgroup 3 (68 children), the older children presented more frequently myopia (p = 0.02) while the younger ones esotropia (p = 0.02) and alteration in smooth pursuit (p = 0.03) and saccades (p < 0.01). Furthermore, fixation, smooth pursuit, visual acuity, contrast sensitivity and visual filed (p < 0.01) were more frequently impaired in younger children (subgroup 1) compared to the older ones. Multiple correspondence analysis (MCA) confirmed the different neurovisual profiles according to age: younger children with CP showed more signs of CVI compared to the older ones. 34 out of 68 children belonging to subgroup 3 underwent the cognitive visual evaluation; an impairment of cognitive visual skills was detected in 21 subjects.

Conclusion

Younger children with CP showed more signs of CVI compared to the older ones, likely for the physiological maturation of visual system and mechanisms of neuroplasticity. In this direction, we suggest an early neurovisual evaluation to detect any weak visual functions.

From Hemispheric Asymmetry through Sensorimotor Experiences to Cognitive Outcomes in Children with Cerebral Palsy

Recent neuroimaging studies allowed us to explore abnormal brain structures and interhemispheric connectivity in children with cerebral palsy (CP). Behavioral researchers have long reported that children with CP exhibit suboptimal performance in different cognitive domains (e.g., receptive and expressive language skills, reading, mental imagery, spatial processing, subitizing, math, and executive functions). However, there has been very limited cross-domain research involving these two areas of scientific inquiry. To stimulate such research, this perspective paper proposes some possible neurological mechanisms involved in the cognitive delays and impairments in children with CP. Additionally, the paper examines the ways motor and sensorimotor experience during the development of these neural substrates could enable more optimal development for children with CP. Understanding these developmental mechanisms could guide more effective interventions to promote the development of both sensorimotor and cognitive skills in children with CP.

Neurodevelopmental Profile in Children Affected by Ocular Albinism

AIM

The aim of this study was to detail the neurodevelopmental profile of subjects affected by ocular albinism (OA) and to collect data on GPR143 gene analysis.

DESIGN

The design of the study involves a retrospective longitudinal observational case series.

METHODS

We collected data on the neurodevelopmental profile of 13 children affected by OA from clinical annual assessments conducted for a period of 6 years after the first evaluation. We described visual profile, neuromotor development and neurological examination, cognitive profile, communication and language skills and behavioral characteristics. The GPR143 gene analysis was performed as well.

RESULTS

Children presented a variable combination of ocular and oculomotor disorders unchanged during the follow-up, a deficit in visual acuity and in contrast sensitivity that progressively improved. Abnormalities in pattern visual evoked potential were found. No deficits were detected at neurological examination and neuromotor development except for a mild impairment in hand-eye coordination observed in five cases. A language delay was observed in five cases, two of whom had also a developmental quotient delay at 2 years evolving to a borderline/deficit cognitive level at preschool age, difficulties in adaptive behavior and autistic-like features were found. Mutations in the GPR143 gene were identified in the two patients who presented the most severe clinical phenotype.

CONCLUSION

Children with OA may share, in addition to a variable combination of ocular signs and symptoms, a neurodevelopment impairment regarding mostly the cognitive, communicative, and social area, especially those with GPR143 mutation.

Vision Abnormalities in Children and Young Adults With Cerebral Palsy; A Systematic Review

AIM

The current study was designed to provide detailed information on the prevalence of ocular abnormalities in patients with cerebral palsy (CP).

METHODS

Four international online scientific databases, including Web of Science, PubMed, Scopus, and Google Scholar were systemically searched. First, the titles of the articles were evaluated, and if relevant, their abstracts and full texts were reviewed. The quality of the studies was assessed using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist.

RESULTS

A total of 147 articles were found in the initial search. After applying the exclusion criteria, 65 articles were chosen for further review, from which 17 articles, comprising a total of 1734 patients with CP ranging in age from birth to 22 years, passed the STROBE quality check and were included in this review. The prevalence of ocular abnormalities in the CP patients reported in the evaluated studies ranged between 34% to 100%, with refractive error, strabismus, and nystagmus exhibiting the greatest overall prevalence at 52%, 48%, and 11%, respectively in this population.

CONCLUSION

Early ocular assessment of children with CP is essential for an accurate diagnosis, personalized rehabilitation and performing early interventions to improve their visual function.

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.

Abnormal Vestibular-Ocular Reflexes in Children With Cortical Visual Impairment

BACKGROUND

To determine whether the vestibular-ocular reflexes (VORs) can be affected by central nervous system injury in children with cortical visual impairment (CVI).

METHODS

Retrospective case series. Twenty consecutive children with CVI who presented to a pediatric ophthalmology practice over an 18-month period were included in the study. Horizontal and vertical VORs were assessed by a pediatric neuro-ophthalmologist using the standard doll's head maneuver. MRI studies were independently reviewed by a pediatric neuroradiologist in a masked fashion. The main outcome measures were the integrity of the VORs and the presence of brainstem abnormalities on MRI.

RESULTS

VORs were found to be absent or severely impaired in 13/20 (65%) children with CVI. More surprisingly, the doll's head maneuver failed to substantially overcome the deviated eye position in 8/13 (62%) children with conjugate gaze deviations. Reduced brainstem size and signal abnormalities were found in 4/7 children with normal VORs and in 9/13 children with abnormal VORs (P = 0.6), showing noncorrelation with the integrity of the VOR.

CONCLUSION

VORs are commonly impaired in children with CVI. This ocular motor deficit reflects the diffuse cortical and subcortical injury that often accompanies perinatal injury to the developing brain. Consequently, these children may lack important visual compensatory mechanisms to stabilize gaze during head movements. This knowledge can help in planning visual rehabilitation.

Early visual training and environmental adaptation for infants with visual impairment

AIM

To evaluate the effectiveness of early visual training and environmental adaptation on visual function and neurological development in infants with visual impairment.

METHOD

This was a pilot intervention clinical trial study. Thirty infants (mean age 5.9mo, SD 2.1mo, range 4-11mo; 16 males, 14 females) with peripheral visual impairment (PVI, n=15) or cerebral visual impairment (CVI, n=15) participated in a 6-month visual intervention programme. Thirty matched infants (mean age 6mo, SD 1.4mo, range 4-9mo; 18 males, 12 females) served as a comparison group. Primary outcome measures were visual acuity, contrast sensitivity, and qualitative ocular motor functions. Secondary outcomes were scores on the Griffiths Mental Developmental Scales (GMDS).

RESULTS

The treatment group showed a significant improvement in all the primary outcomes (p<0.01). The comparison group improved only in visual acuity and contrast sensitivity (p<0.01). The treatment group showed greater improvement than the comparison group in visual fixation (p=0.033) and smooth pursuit (p<0.01). The CVI subgroup showed greater improvement in visual acuity than the PVI subgroup (p<0.01). GMDS subscales of hand-eye coordination (p=0.01) and performance (p<0.01) increased in the treatment group, while the total score of the comparison group decreased, driven by language (p=0.039) and hand-eye coordination (p=0.025) subscales.

INTERPRETATION

Results suggest that, in infants with visual impairment, visual function and certain developmental outcomes improve in response to early visual training and environmental adaptation, in an interactive context. What this paper adds Early visual training and environmental adaptation are associated with enhanced visual acuity and smooth pursuit. Early visual training and environmental adaptation are associated with an improvement of neurological developmental outcome. Performance, hand-eye coordination, and language scores in Griffiths Mental Developmental Scales increase after visual training. After training, visual acuity improves more in infants with cerebral rather than anterior visual impairment. Type and complexity of visual impairment contribute to determine infants' response to training.

Visual Impairment and Functional Classification in Children with Cerebral Palsy

BACKGROUND

Cerebral palsy (CP) is the most common motor impairment in childhood and often accompanied by a broad spectrum of comorbidities. Data are sparse concerning visual impairment (VI) and functional classification among CP children.

OBJECTIVE

The objective of this study was to analyze the prevalence of VI among children with CP and to investigate a possible association between VI and Gross Motor Function Classification System (GMFCS) and the Bimanual Fine Motor Function (BFMF).

METHODS

In this hospital-based study, records of 200 children with CP aged 2 to 17 years were reviewed.

RESULTS

Overall, VI was found in 59.5% of children with CP. Prevalence of VI was higher when compared with non-CP children. A correlation between GMFCS as well as BFMF and severity of VI was found. Children with severe CP were at greater risk for severe VI, especially cerebral VI compared with children with mild CP.

CONCLUSION

VI is a significant problem in children with CP and is correlated with motor function. Children with CP should undergo detailed ophthalmologic and orthoptic assessment to enable early intervention.

Physician Prescribing and Referral Patterns in Children with Cerebral Visual Impairment

SIGNIFICANCE

Cerebral visual impairment (CVI) is the leading cause of visual impairment in the developed world. Providing children with CVI with the appropriate treatment ensures the best possible visual outcome and potentially improves quality of life.

PURPOSE

The purpose of this study was to determine physician prescribing and visual rehabilitation referral patterns in children with CVI.

METHODS

A retrospective chart review was completed on children with CVI examined at Cincinnati Children's Hospital Medical Center from January 1, 2008, to March 1, 2018. Significant refractive error warranting correction was determined using the American Academy of Ophthalmology Preferred Guidelines and the American Association for Pediatric Ophthalmology and Strabismus Vision Screening Committee Guidelines. The CVI Range was used as a surrogate to categorize CVI severity.

RESULTS

A total of 194 children were included. Sixty-eight (35%) had refractive error warranting correction and were prescribed glasses (group RC), 99 (51%) did not have refractive error warranting correction and were not prescribed glasses (group NRNC), 20 (10%) had refractive error warranting correction but were not prescribed glasses (group RNC), and 7 (4%) did not have refractive error warranting correction but were prescribed glasses (group NRC). There was greater than one-line Snellen equivalent difference between group RC (20/156) and group RNC (20/221). There was greater than six-line Snellen equivalent difference between group NRNC (20/149) and group NRC (20/35). Mean CVI Range score 2 values for each group were 5.9, 4.6, 4.8, and 7.1.

CONCLUSIONS

Children with less severe CVI were less likely to have significant refractive error but given glasses. Despite significant refractive error, children with more severe CVI were not prescribed glasses. Children with very low visual function were not prescribed glasses as frequently, possibly limiting their visual rehabilitation. Providers should ensure that all children with CVI are correctly prescribed glasses to provide the best possible visual outcome.

Weaker Connectivity of the Cortical Networks Is Linked with the Uncharacteristic Gait in Youth with Cerebral Palsy

Cerebral palsy (CP) is the most prevalent pediatric neurologic impairment and is associated with major mobility deficiencies. This has led to extensive investigations of the sensorimotor network, with far less research focusing on other major networks. The aim of this study was to investigate the functional connectivity (FC) of the main sensory networks (i.e., visual and auditory) and the sensorimotor network, and to link FC to the gait biomechanics of youth with CP. Using resting-state functional magnetic resonance imaging, we first identified the sensorimotor, visual and auditory networks in youth with CP and neurotypical controls. Our analysis revealed reduced FC among the networks in the youth with CP relative to the controls. Notably, the visual network showed lower FC with both the sensorimotor and auditory networks. Furthermore, higher FC between the visual and sensorimotor cortices was associated with larger step length (r = 0.74, p_FDR = 0.04) in youth with CP. These results confirm that CP is associated with functional brain abnormalities beyond the sensorimotor network, suggesting abnormal functional integration of the brain’s motor and primary sensory systems. The significant association between abnormal visuo-motor FC and gait could indicate a link with visuomotor disorders in this patient population.

Social cognition in individuals born preterm

Faces hold a substantial value for effective social interactions and sharing. Covering faces with masks, due to COVID-19 regulations, may lead to difficulties in using social signals, in particular, in individuals with neurodevelopmental conditions. Daily-life social participation of individuals who were born preterm is of immense importance for their quality of life. Here we examined face tuning in individuals (aged 12.79 ± 1.89 years) who were born preterm and exhibited signs of periventricular leukomalacia (PVL), a dominant form of brain injury in preterm birth survivors. For assessing the face sensitivity in this population, we implemented a recently developed experimental tool, a set of Face-n-Food images bordering on the style of Giuseppe Arcimboldo. The key benefit of these images is that single components do not trigger face processing. Although a coarse face schema is thought to be hardwired in the brain, former preterms exhibit substantial shortages in the face tuning not only compared with typically developing controls but also with individuals with autistic spectrum disorders. The lack of correlations between the face sensitivity and other cognitive abilities indicates that these deficits are domain-specific. This underscores impact of preterm birth sequelae for social functioning at large. Comparison of the findings with data in individuals with other neurodevelopmental and neuropsychiatric conditions provides novel insights into the origins of deficient face processing.

Utilising the Orthoptic Skill Set to Improve Access to Eye Care for Adults with Severe/Profound Learning Disabilities-A Service Evaluation

Intro:

There is a wealth of research evidencing the high incidence of visual impairment (VI) and poor uptake of eye care services by adults with learning disabilities (LD). Despite this, very few authorities within England currently provide the additional support required by those with severe/profound LD (S/PLD).

Method:

By means of an initial funded pilot study, an unmet need was evidenced locally and a small service established to improve access to eye care for adults with S/PLD. Operational since 2007, this service has provided evidence to support the campaign for a nationally funded eye care pathway.

This service evaluation outlines the initial service set up, aims and objectives, and provides an analysis of the current service by means of a detailed breakdown of service-user outcomes during a sample 5-year period.

Results:

Orthoptic home visits (OHV) revealed high levels of strabismus (54.4%), refractive error (43.3%), cataracts (23.3%), and many other ophthalmic conditions (29%). Over a quarter of the adults with LD (26.6%) were certified as VI and 61% of people were provided with tailored strategies, the majority of which were for visual processing difficulties.

Conclusion:

The prospect of a nationally funded eye care pathway for adults with LD in England is now a real possibility. This service model has identified a clearly defined unmet need and illustrates the unique skill set orthoptists can offer to address this health inequality. Requiring minimal financial outlay and flexible enough to be integrated into any future national eye care framework, this service has ensured that access to eye care is truly equitable for all people with LD.

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.

Visual function subtyping in children with early-onset cerebral visual impairment

AIM

To develop a data-driven subgrouping method to identify and profile subtypes of early-onset childhood cerebral visual impairment (CVI).

METHOD

Sixty-three children with suspected or diagnosed congenital CVI were recruited (28 males, 35 females, median age=8y, range=5-16y). Cognitive, basic, and higher-order vision functions were assessed and quality of life, functional vision questionnaire, neurodevelopmental, and ophthalmological data were collected. Cluster analysis and other statistical analyses were undertaken to determine and validate the subgrouping.

RESULTS

Forty-three participants completing the full test battery were included in cluster analysis, revealing two subgroups. Group A1 (n=15) showed selective visual perception and visuomotor deficits. Group A2 (n=28) showed more severe and broader visual perception and visuomotor deficits, and variable visual acuity. A third, lower-functioning group, Group B (n=20), was differentiated and showed significant visual acuity reduction compared with Group A (p<0.001, V=0.69). External validation showed significant cooccurring ophthalmological (e.g. strabismus p<0.001, V=0.59) and motor impairment differences (χ² =16.26, p<0.001, V=0.51) between the three groups. All groups had lowered parent-reported quality of life and everyday functional vision.

INTERPRETATION

Statistical analyses revealed three subgroups with differentiated vision function characteristics on a gradient of severity. The subgrouping method provides the first steps in developing a novel classification system to underpin future clinical diagnostics and profiling of early-onset CVI.

WHAT THIS PAPER ADDS

Three data-driven subgroups of vision function deficits were identified. A similar severity gradient was shown in cooccurring cognitive and neurodevelopmental deficits. Reported quality of life and functional vision difficulties were low across all groups.

Visual impairment and perceptual visual disorders in children with cerebral palsy in Nigeria

Cerebral palsy (CP) is the most common cause of childhood physical disability globally. This study describes the spectrum of ocular morbidity and visual impairment in a community-based (recruited by key informants) sample of children with CP in Cross River State, Nigeria.

METHODS

A paediatric neurologist clinically confirmed CP and assessed systemic comorbidity. Ophthalmological assessment included developmental age appropriate acuity tests, objective refraction and objective and subjective tests of perceptual visual dysfunction (PVD).

RESULTS

388 children aged 4-15 years with CP were identified. Visual problems were reported by carers in only 55 (14%) cases. Binocular visual acuity impairment was seen in 20/201 by Lea symbols test (10%) and 213/388 (55%) by the mirror test. Abnormal visual fields were seen in 58/388 (14.9%); strabismus in 183 (47%) abnormal contrast sensitivity in 178 (46%) and abnormal saccades in 84 (22%), spherical refractive errors in 223 (58%), significant astigmatism in 36 (12%), accommodative dysfunction in 41 (10.6%), optic atrophy in 198 (51%). Perceptual visual disorders were present in 22 (6%) subjectively and 177 (46%) objectively. The estimated frequency of cerebral visual impairment (CVI) in children ranged from 61 (16%) to 191 (49%) if children with optic atrophy were included.

CONCLUSION

Children with CP have a wide spectrum of ocular morbidity and visual impairment, underestimated by carers. Children with CP require visual acuity assessments with a range of tests which account for associated comorbidities and oculomotor dysfunction. Functional vision assessments for PVD is important. CVI is common.

Risk factors of strabismus surgery among pediatric cerebral palsy population with strabismus in Taiwan: A population-based cohort study

BACKGROUND

To identify the risk factors of strabismus surgery among Taiwanese children with severe cerebral palsy (CP) and strabismus.

METHODS

This retrospective nationwide population-based cohort study examined a cohort of newly diagnosed pediatric CP patients (age ≤ 10 y) between 1997 and 2013 with strabismus. The primary endpoint was strabismus surgery. A stepwise logistic regression was applied to determine the demographic factors, ophthalmic conditions, and comorbidities associated with strabismus surgery.

RESULTS

Out of 808 patients, 115 had received strabismus surgery. The significant factors correlated to strabismus surgery in pediatric patients with severe CP and strabismus were CP diagnosis age < 4 years, residency in a suburban/rural area, low birth weight, and strabismic amblyopia.

CONCLUSION

In CP children with strabismus who have risk factors of younger CP diagnosis age (age < 4 y), residency in a suburban/rural area, a low birthweight, and the presence of strabismic amblyopia, strabismus surgery should be considered.

Eye Gaze Gaming Intervention in Children with Dyskinetic Cerebral Palsy: A Pilot Study of Task Performance and Its Relation with Dystonia and Choreoathetosis

OBJECTIVES

To investigate the operational competences screen navigation and dwell function underlying eye gaze performance, and the relation of dystonia and choreoathetosis with eye gaze performance in children with dyskinetic cerebral palsy (DCP).

METHODS

During a 5-week intervention, ten participants with DCP played eye gaze video games daily for 30 minutes. Six games were used to assess task performance, fixation count, and eye movement accuracy during four measurements. Dystonia and choreoathetosis were evaluated using the Dyskinesia Impairment Scale.

RESULTS

Eye gaze performance improved over time (p = .013). Moderate to strong within-subject correlations were found between eye movement accuracy and task performance, and between eye movement accuracy and fixation count. No significant correlations were found with the movement disorders.

CONCLUSIONS

Eye gaze technology shows great potential to be a successful computer interface for children with severe DCP, thereby potentially improving their communication skills, participation levels, and quality of life.

Structural brain damage and visual disorders in children with cerebral palsy due to periventricular leukomalacia

•

There is a strong correlation between brain lesion severity and visual function, evident also with a Structural MRI.

•

It is confirmed the validity of MRI semi-quantitative scale published by Fiori et al. (2014).

•

There is a frequent association of PVL with thalamic lesions with important repercussion on visual function.

Aim

To systematically explore the relationship between type and severity of brain lesion on Magnetic Resonance Imaging (MRI) and visual function in a large cohort of children with periventricular leukomalacia (PVL).

Methods

94 children with bilateral cerebral palsy (CP) and history of PVL were recruited at Stella Maris Scientific Institute in Pisa (Italy). We included data of participants (72) with at least one MRI after the age of three years and an evaluation of visual function including fixation, following, saccades, nystagmus, acuity, visual field, stereopsis and color perception.

Brain lesions location and extent were assessed by a semi-quantitative MRI-scale for children with CP.

Results

Brain lesion severity strongly correlated with visual function total score (global MRI score p = .000; hemispheric score p = .001 and subcortical score p = .000). Moreover, visual acuity, visual field, stereopsis and colour were compromised when a cortical damage was present, while ocular motricity (and in particular fixation and saccades) were compromised in presence of subcortical brain damage.

Interpretation

Structural MRI is valuable for understanding the relationship between brain lesion severity and visual function in children with CP.

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.

Beyond the eye: Cortical differences in primary visual processing in children with cerebral palsy

•

Visual processing deficits are common in children with CP.

•

MEG was used to image multispectral cortical oscillations during visual processing.

•

Compared with controls, children with CP had weaker occipital oscillations.

•

Aberrant cortical oscillations likely impact early visual processing abilities.

Despite the growing clinical recognition of visual impairments among people with cerebral palsy (CP), very few studies have evaluated the neurophysiology of the visual circuitry. To this end, the primary aim of this investigation was to use magnetoencephalography and beamforming methods to image the relative change in the alpha–beta and gamma occipital cortical oscillations induced by a spatial grating stimulus (e.g., visual contrast) that was viewed by a cohort of children with CP and typically-developing (TD) children. Our results showed that the high-contrast, visual gratings stimuli induced a decrease in alpha–beta (10 – 20 Hz) activity, and an increase in both low (40 – 56 Hz) and high (60 – 72 Hz) gamma oscillations in the occipital cortices. Compared with the TD children, the strength of the frequency specific cortical oscillations were significantly weaker in the children with CP, suggesting that they had deficient processing of the contrast stimulus. Although CP is largely perceived as a musculoskeletal centric disorder, our results fuel the growing impression that there may also be prominent visual processing deficiencies. These visual processing deficits likely impact the ability to perceive visual changes in the environment.

Morpho-functional survey in children suspected of inherited retinal dystrophies via video recording, electrophysiology and genetic analysis

PURPOSE

To present a detailed study matching functional response and video imaging with genetic analysis in children suspected of inherited retinal dystrophy (IRD).

METHODS

Sixteen children underwent fundus examination via video recording (Heine Omega 500 indirect ophthalmoscope with DV1 camera) and electroretinogram (ERG) under general anesthesia to investigate the cause of suspected low vision. The patients [median age 12 (interquartile range 8-57.5) months] had associated genetic analysis performed with next-generation sequencing or array-comparative genomic hybridization.

RESULTS

Four children had potential pathogenic variants in genes involved in Leber congenital amaurosis and Joubert syndrome (NMNAT1, CEP290, KCNJ13, IMPDH1); 1 child had a 16p11.2 microdeletion and 1 in 2q22.1. The ERG was altered in 6 patients, fundus imaging showed serious abnormality matching an IRD in 7 children, and less severe fundus alterations were found in 2 subjects.

CONCLUSION

Fundus imaging associated with ERG may be significant in IRD diagnosis and visual impairment prognosis, alongside genetic analysis and therapy in selected cases.

Human visual skills for brain-computer interface use: a tutorial

Background and objectives: Many brain-computer interfaces (BCIs) for people with severe disabilities present stimuli in the visual modality with little consideration of the visual skills required for successful use. The primary objective of this tutorial is to present researchers and clinical professionals with basic information about the visual skills needed for functional use of visual BCIs, and to offer modifications that would render BCI technology more accessible for persons with vision impairments.Methods: First, we provide a background on BCIs that rely on a visual interface. We then describe the visual skills required for BCI technologies that are used for augmentative and alternative communication (AAC), as well as common eye conditions or impairments that can impact the user's performance. We summarize screening tools that can be administered by the non-eye care professional in a research or clinical setting, as well as the role of the eye care professional. Finally, we explore potential BCI design modifications to compensate for identified functional impairments. Information was generated from literature review and the clinical experience of vision experts.Results and conclusions: This in-depth description culminates in foundational information about visual skills and functional visual impairments that affect the design and use of visual interfaces for BCI technologies. The visual interface is a critical component of successful BCI systems. We can determine a BCI system for potential users with visual impairments and design BCI visual interfaces based on sound anatomical and physiological visual clinical science.Implications for RehabilitationAs brain-computer interfaces (BCIs) become possible access methods for people with severe motor impairments, it is critical that clinicians have a basic knowledge of the visual skills necessary for use of visual BCI interfaces.Rehabilitation providers must have a knowledge of objectively gathering information regarding a potential BCI user's functional visual skills.Rehabilitation providers must understand how to modify BCI visual interfaces for the potential user with visual impairments.Rehabilitation scientists should understand the visual demands of BCIs as they develop and evaluate these new access methods.

Relationship between brain structure and Cerebral Visual Impairment in children with Cerebral Palsy: A systematic review

BACKGROUND

Cerebral Visual Impairment (CVI) is very common yet often unrecognised visual dysfunction in children with Cerebral Palsy (CP). Magnetic Resonance Imaging (MRI) is the diagnostic tool in the investigation of brain lesions in children with CP and CVI.

AIM

The aim of this systematic review is to evaluate the relationship between brain structure and CVI, as determined by MRI in children with CP.

METHODS AND PROCEDURES

A comprehensive search of 5 database (PubMed, EMBASE, SCOPUS, CINAHL and Cochrane Database) was undertaken up until June 2019. The PRISMA checklist was then utilised to report on the process of selecting eligible papers. A total of 30 observational studies met the full inclusion criteria. Further, STROBE checklist was employed to report on the observational studies.

OUTCOMES AND RESULTS

Periventricular leucomalacia on MRI was found to have a strong association with CVI in all 30 studies. Only 13 (43 %) studies described dorsal and/ ventral stream dysfunction. There was ambiguity in the definition of CVI.

CONCLUSIONS AND IMPLICATIONS

The overall level of evidence correlating different patterns of CVI and CP (based on GMFCS, motor type and distribution) and MRI was low. Further studies utilising advances in MRI are needed to understand brain reorganisation and patterns of CVI and suggest rehabilitation therapy inclusive of vision.

Visual Function Classification System for children with cerebral palsy: development and validation

AIM

To develop and validate the Visual Function Classification System (VFCS), which was created to classify how children with cerebral palsy (CP) use visual abilities in daily life.

METHOD

The process of development and validation of the VFCS involved four phases: (1) drafting of the five levels from the analysis of literature and clinical experience; (2) validation of constructs and revision of the levels for concept meaningfulness, using nominal group process; (3) refinement by international Delphi survey; and(4) assessment of interrater reliability among professionals and with caregivers, and of test-retest reliability.

RESULTS

Five nominal groups involved 29 participants; 65 people completed the first round and 51 the second round of the Delphi survey. Construct validity was demonstrated within an expert group and external validation through several stakeholders, with the involvement of patients and families to ensure meaningfulness of the concept. Discussions continued until consensus was reached about the construct and content of the five levels. Participants in the reliability study included 29 professionals, 39 parents, and a total sample of 160 children with CP (mean age [SD] 6y 6mo [3y 4mo]; median 5y 7mo, range 1-19y). Absolute interrater agreement among professionals was 86% (weighted κ=0.88; 95% confidence interval [CI] 0.83-0.93). Test-retest reliability was high (weighted κ=0.97; 95% CI 0.95-0.99). Parent-professional interrater reliability on 39 children was moderate (weighted κ=0.51; 95% CI 0.39-0.63).

INTERPRETATION

The VFCS has been appropriately constructed and provides a reliable system to classify visual abilities of children with CP both in clinical and in research settings.

WHAT THIS PAPER ADDS

The Visual Function Classification System is a valid and reliable system. It classifies visual abilities of children with cerebral palsy in clinical and research settings. At a clinical level, it can be used to harmonize communication among professionals and identify patients' strengths and weaknesses. In research settings, it can be used to stratify patients, define natural history evolution, and interpret intervention studies.

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.

Assessment tool for visual perception deficits in cerebral visual impairment: reliability and validity

AIM

To evaluate the reliability and validity of the Children's Visual Impairment Test for 3- to 6-year-olds (CVIT 3-6).

METHOD

Reliability was assessed via test-retest correlation and intraclass correlation coefficient (ICC) in typically developing children, children with cerebral visual impairment (CVI), intellectual impairment, and simulated impaired vision (validation groups n=59, mean developmental age=4y 10mo, 27 females, 32 males). Internal validity was evaluated with a confirmatory factor analysis on the normative sample (n=301, median age=4y 8mo, SD=9.7mo, 148 females, 153 males). External validity was assessed by correlating performance on CVIT 3-6 with L94, the Beery-Buktenica Developmental Test of Visuo-Motor Integration (Beery-VMI), the Freiburg Vision Test, the revised Snijders-Oomen Nonverbal Intelligence Test for children between 2 years 6 months and 7-years-old (SON-R 2.5-7), and the Social Responsiveness Scale (SRS) questionnaire and by comparing performance between validation groups.

RESULTS

We observed very good test-retest reliability (r=0.82, p<0.001, ICC=0.80) and confirmed the hypothesized factor structure (comparative fit index=1; Tucker-Lewis index=1.045). We found high correlations with tests with a strong visual perception component (L94: r=0.74, p<0.001; SON-R 2.5-7: r=0.37, p=0.01) and low correlations with other tests (Beery-VMI: r=0.25, p=0.09; SRS: r=0-0.26, p=0.09). Lowest scores were observed for children with CVI compared to the other validation groups (F[3,44]=5.1, p=0.003).

INTERPRETATION

CVIT 3-6 is grounded in knowledge of visual perception. The tool specifically measures CVI-related visual perception deficits and is not mediated by intellectual abilities or low visual acuity.

WHAT THE PAPER ADDS

Evidence for good test-retest reliability of the Children's Visual Impairment Test for 3- to 6-year-olds (CVIT 3-6). Factor structure of normative data reflects CVIT 3-6's foundations in vision science. CVIT 3-6 specifically measures visual perception impairments. CVIT 3-6 performance is not influenced by intelligence or low visual acuity.

Visuospatial Attention and Saccadic Inhibitory Control in Children With Cerebral Palsy

Cerebral palsy (CP) is a non-progressive syndrome due to a pre-, peri- or post-natal brain injury, which frequently involves an impairment of non-motor abilities. The aim of this article was to examine visuospatial attention and inhibitory control of prepotent motor responses in children with CP showing a normal IQ or mild cognitive impairment, measuring their performance in oculomotor tasks. Ten children (9–16-year-old) with spastic CP and 13 age-matched, typically developing children (TDC) participated in the study. Subjects performed a simple visually-guided saccade task and a cue-target task, in which they performed a saccade towards a peripheral target, after a non-informative visual cue was flashed 150 ms before the imperative target, either at the same (valid) or at a different (invalid) spatial position. Children with CP showed severe executive deficits in maintaining sustained attention and complying with task instructions. Furthermore, saccadic inhibitory control appeared to be significantly impaired in the presence of both stimulus-driven and goal-directed captures of attention. In fact, patients showed great difficulties in suppressing saccades not only to the cue stimuli but also to the always-present target placeholders, which represented powerful attentional attractors that had to be covertly attended throughout the task execution. Moreover, impairment did not affect in equal manner the whole visual field but showed a marked spatial selectivity in each individual subject. Saccade latencies in the cue-target task were faster in the valid than in the invalid condition in both child groups, indicating the preservation of low-level visuospatial attentive capabilities. Finally, this study provides evidence that these impairments of executive skills and in inhibitory control, following early brain injuries, manifest in childhood but recover to virtually normal level during adolescence.

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.

Autism in Children With Cerebral and Peripheral Visual Impairment: Fact or Artifact?

The aim of this study was to evaluate the occurrence and clinical characteristics of autism spectrum disorder in visually impaired children. In total, 273 participants, 214 with cerebral causes of vision impairment and 59 with peripheral causes, were assessed using multiple assessment methods and adapted for individuals with vision loss. We found that autism spectrum disorder was more prevalent in the visually impaired compared to general population, and that the prevalence varied according to the type of visual disorder (2.8% for cerebral and 8.4% for peripheral visual impairment). In subjects with cerebral visual impairment, the presence of autistic symptoms was consistent with the diagnosis of autism spectrum disorder. In children with peripheral visual impairment, certain symptoms related to visual loss overlapped with the clinical features of autism spectrum disorder, thus making clinical diagnosis more challenging. The development of assessment tools that take into account the type and level of visual impairment and validation testing in a larger population sample are needed in order to confirm these initial findings regarding the diagnosis of autism spectrum disorder in visually impaired children.