Cerebral Visual Impairment Research Articles

Clinical study of esodeviations in children

Esotropia or convergent strabismus is a common type of squint in children. The esodeviation, the refractive error and the amblyopia should be examined and treated early to achieve good cosmetic correction and to improve Visual acuity.A meticulous history of 25 children up to age of 12 years who presented with esodeviations was taken including the age of onset, duration and previous treatment. They were examined for amount and type of deviation by cover test, hirschberg corneal reflex test, Prism bar cover test and evaluated for refractive error under full cycloplegic correction, for Binocular Single Vision, diplopia, suppression and amblyopia by Worth four-dot test and RAF ruler. Ocular movements and fundus findings were recorded.11 male and 14 female children with esodeviations with age of presentation varying from 9 months to 12 years were evaluated for type of esotropia. In our study the most common type seen in 12 cases (48%) is refractive accommodative esotropia with high hypermetropia. Non-refractive accommodative esotropia greater for near with high AC/A ratio in 5 patients (20%), Partially accommodative (mixed) esotropia in 2 cases, acquired non-accommodative esotropia seen in 2 patients. 1 case each is seen in Infantile esotropia, in Sensory esotropia, in child with Duane’s retraction syndrome (DRS) and in child having cerebral visual impairment (CVI).Our study aimed to diagnose and manage the various types of esodeviations at an early age so as to maintain binocular alignment and a good Visual acuity to avoid progression to amblyopia.

Cerebral visual impairment: genetic diagnoses and phenotypic associations

BackgroundCerebral visual impairment (CVI) is the most common form of paediatric visual impairment in developed countries. CVI can arise from a host of genetic or acquired causes, but there has...

Providing quality care for people with CDKL5 deficiency disorder: A European expert panel opinion on the patient journey.

Cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder (CDD) is a developmental and epileptic encephalopathy caused by variants in the CDKL5 gene. The disorder is characterized by intractable early-onset seizures, severe neurodevelopmental delay, hypotonia, motor disabilities, cerebral (cortical) visual impairment and microcephaly. With no disease-modifying therapies available for CDD, treatment is symptomatic with an initial focus on seizure control. Another unmet need in the management of people with CDD is the lack of evidence to aid standardized care and guideline development. To address this gap, experts in CDD and representatives from patient advocacy groups from Denmark, Finland, France, Germany, Italy, Poland, Spain, and the United Kingdom convened to form an Expert Working Group. The aim was to provide an expert opinion consensus on how to ensure quality care in routine clinical practice within the European setting, including in settings with limited experience or resources for multidisciplinary care of CDD and other developmental and epileptic encephalopathies. By means of one-to-one interviews around the current treatment landscape in CDD, insights from the Expert Working Group were collated and developed into a Europe-specific patient journey for individuals with CDD, which was later validated by the group. Further discussions followed to gain consensus of opinions on challenges and potential solutions for achieving quality care in this setting. The panel recognized the benefit of early genetic testing, a holistic personalized approach to seizure control (taking into consideration various factors such as concomitant medications and comorbidities), and age- and comorbidity-dependent multidisciplinary care for optimizing patient outcomes and quality of life. However, their insights and experiences also highlighted much disparity in management approaches and resources across different European countries. Development of standardized European recommendations is required to align realistic diagnostic criteria, treatment goals, and management approaches that can be adapted for different settings. PLAIN LANGUAGE SUMMARY: Cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder (CDD) is a rare condition caused by a genetic mutation with a broad range of symptoms apparent from early childhood, including epileptic seizures that do not respond to medication and severe delays in development. Due to the lack of guidance on managing CDD, international experts and patient advocates discussed best practices in the care of people with CDD in Europe. The panel agreed that early testing, a personalized approach to managing seizures,and access to care from different disciplines are beneficial. Development of guidelines to ensure that care is standardized would also be valuable.

Effects of a guideline for children with cerebral visual impairment on the daily practices of vision habilitation and rehabilitation workers

To support vision rehabilitation workers, an intervention guideline for the rehabilitation of children with cerebral visual impairment (CVI) was developed. It combines currently available theoretical and practice-based knowledge in the domains of academic performance and mobility. The aim of this study was to evaluate the perceived value of the guideline by professionals. Two studies were performed. First, a process analysis of the guideline was performed to evaluate its strengths and weaknesses. Eleven therapists used a concept of the guideline for 3 months and were interviewed about their expectations (before) and experiences (afterwards). In a second study, the guideline was introduced to 24 professionals working with school-aged children with CVI. The participants filled in a short survey with five questions about their perceived knowledge of and skills in dealing with CVI. The guideline complied with the expectations of the professionals, and the professionals improved in knowledge of CVI and the ability to explain what CVI is. The survey results indicated improvement in self-confidence to perform CVI-specific interventions, and the interviews also showed professionals had expected to learn more options for intervention. After training, the professionals felt more secure about their interventions while using the guideline. This was probably caused by an improvement in their knowledge about CVI and about available interventions. However, the improvement was small and still not perfect and could be enlarged by adding more concrete intervention suggestions to the guideline. The intervention guideline for CVI offers an overview of available theoretical and practice-based knowledge. Improvement in knowledge on CVI can be used directly in rehabilitation practices. A great advantage of the guideline is that therapists are now better prepared to explain the nature and consequences of CVI to a client.

GABAergic/Glycinergic and Glutamatergic Neurons Mediate Distinct Neurodevelopmental Phenotypes of STXBP1 Encephalopathy.

An increasing number of pathogenic variants in presynaptic proteins involved in the synaptic vesicle cycle are being discovered in neurodevelopmental disorders. The clinical features of these synaptic vesicle cycle disorders are diverse, but the most prevalent phenotypes include intellectual disability, epilepsy, movement disorders, cerebral visual impairment, and psychiatric symptoms ( Verhage and Sørensen, 2020; Bonnycastle et al., 2021; John et al., 2021; Melland et al., 2021). Among this growing list of synaptic vesicle cycle disorders, the most frequent is STXBP1 encephalopathy caused by de novo heterozygous pathogenic variants in syntaxin-binding protein 1 (STXBP1, also known as MUNC18-1; Verhage and Sørensen, 2020; John et al., 2021). STXBP1 is an essential protein for presynaptic neurotransmitter release. Its haploinsufficiency is the main disease mechanism and impairs both excitatory and inhibitory neurotransmitter release. However, the disease pathogenesis and cellular origins of the broad spectrum of neurological phenotypes are poorly understood. Here we generate cell type-specific Stxbp1 haploinsufficient male and female mice and show that Stxbp1 haploinsufficiency in GABAergic/glycinergic neurons causes developmental delay, epilepsy, and motor, cognitive, and psychiatric deficits, recapitulating majority of the phenotypes observed in the constitutive Stxbp1 haploinsufficient mice and STXBP1 encephalopathy. In contrast, Stxbp1 haploinsufficiency in glutamatergic neurons results in a small subset of cognitive and seizure phenotypes distinct from those caused by Stxbp1 haploinsufficiency in GABAergic/glycinergic neurons. Thus, the contrasting roles of excitatory and inhibitory signaling reveal GABAergic/glycinergic dysfunction as a key disease mechanism of STXBP1 encephalopathy and suggest the possibility to selectively modulate disease phenotypes by targeting specific neurotransmitter systems.

Visual search patterns during exploration of naturalistic scenes are driven by saliency cues in individuals with cerebral visual impairment

We investigated the relative influence of image salience and image semantics during the visual search of naturalistic scenes, comparing performance in individuals with cerebral visual impairment (CVI) and controls with neurotypical development. Participants searched for a prompted target presented as either an image or text cue. Success rate and reaction time were collected, and gaze behavior was recorded with an eye tracker. A receiver operating characteristic (ROC) analysis compared the distribution of individual gaze landings based on predictions of image salience (using Graph-Based Visual Saliency) and image semantics (using Global Vectors for Word Representations combined with Linguistic Analysis of Semantic Salience) models. CVI participants were less likely and were slower in finding the target. Their visual search behavior was also associated with a larger visual search area and greater number of fixations. ROC scores were also lower in CVI compared to controls for both model predictions. Furthermore, search strategies in the CVI group were not affected by cue type, although search times and accuracy showed a significant correlation with verbal IQ scores for text-cued searches. These results suggest that visual search patterns in CVI are driven mainly by image salience and provide further characterization of higher-order processing deficits observed in this population.

Abstract WP223: Cerebral Visual Impairment in ACTA2 Patients Assessed by Virtual Reality Testing

Introduction: Heterozygous missense mutations disrupting arginine 179 (Arg179) in the ACTA2 gene which codes for the smooth muscle-specific isoform of α-actin, cause Multisystemic Smooth Muscle Dysfunction Syndrome (MSMDS). The clinical manifestations of this genetic condition include congenital mydriasis, patent ductus arteriosus, stroke, and/or aortic aneurysms or dissections among many others. White matter injury, impaired autoregulation, and neurovascular coupling (due to the cerebral vasculopathy affecting cerebral perfusion) are known factors that alter neural network performance and processing speed. The lack of a standardized ophthalmologic examination that detects cerebral visual impairment (CVI), precludes an early diagnosis and creates missed opportunities for intervention. There is a paucity of data regarding CVI in MSMDS patients, and through this novel work, we present data defining their visual processing deficits. Hypothesis: We hypothesize that: 1) individuals with MSMDS will exhibit more pronounced deficits in visual-spatial processing compared to the control group, and 2) their performance will deteriorate as the complexity of visual tasks increases. Methods: Using a virtual reality (VR) based visual search task system, we characterized the impairment of higher-order visual processing in MSMDS patients (n = 4) as compared to healthy controls (n = 13). The VR-based task required searching for targets on a screen among varying levels of visual complexity. Reaction time, gaze error, shifted ellipse area, success rate, and pursuit saccade ratio were statistically analyzed with unpaired group t-tests, with significance being defined as p < 0.05. Results: Compared to controls, MSMDS patients took longer to identify the correct target, were less accurate in finding the target, and exhibited greater impairment in performance with an increasing number of distractors. Both groups showed similar task compliance, measured using an off-screen count metric. Conclusion: This novel work demonstrates that MSMDS patients exhibit impaired higher-order visual processing. This highlights the need for clinical tools that can assess these difficulties with quantitative methods to guide therapies and improve functional outcomes.

Abstract TMP11: Cerebral Visual Impairment in Pediatric Stroke Patients Assessed by Virtual Reality Testing

Introduction: Pediatric stroke is one of the leading causes of disability in children, many of whom incur brain injury affecting critical visual anatomical networks. Dedicated ophthalmologic examinations that detect cerebral visual impairment (CVI) - the leading cause of congenital visual impairment in developed countries - are not standard of care and can delay diagnosis and interventions. There is limited CVI data in pediatric stroke patients, and in this work we present data defining visual processing deficits in pediatric stroke patients. Hypothesis: We hypothesize that pediatric stroke patients will (1) demonstrate greater visual-spatial processing impairments than controls and (2) demonstrate increasing performance impairment as a function of increasing visual task demands. Methods: Using a virtual reality (VR) based visual search task system, we characterized significant deficits in higher-order visual processing of pediatric stroke patients (n = 17) as compared to healthy controls (n = 13). Stroke patients suffered from a perinatal (n = 8) or pediatric (n = 9) stroke - confirmed with brain MRI - affecting various vascular territories of the anterior and posterior circulations. The task required searching for on-screen targets with increasing visual complexity. Metrics such as reaction time, gaze error, shifted ellipse area, success rate, and pursuit saccade ratio were analyzed using unpaired group-level t-tests and considered significant if p < 0.05. Results: Stroke patients took longer to identify the target (p = 0.001), were less accurate in finding it (p = 0.007), and exhibited greater impairment in performance with an increasing number of distractors compared to healthy children. Groups had comparable task compliance, as indexed by an off-screen count metric. Conclusion: This original work demonstrates that pediatric stroke patients, particularly those with strokes affecting the middle cerebral artery and posterior circulation vascular territories, exhibit impaired higher-order visual processing. This highlights the urgent need for standardized clinical testing to provide quantitative performance measures of cortical visual processing. This will allow timely detection and implementation of interventional therapies.

Проблемы идентификации сенсорных нарушений и слепоглухоты у современных детей с врожденными патологиями развития

<p style="text-align: justify;">This review provides an overview of the challenges of identifying dual sensory impairment in children with congenital disabilities. The concept of deafblindness and the special needs of the group with hearing and visual impairments are reviewed. The difficulties of defining this condition due to the heterogeneity of this group are emphasized. The evolution of the etiology of sensory impairment, typical for recent decades, is described, due to the progress of medical science, which makes it possible to keep alive children with severe genetic pathologies and those born considerably prematurely. The characteristics of cerebral hearing and visual impairments, still insufficiently studied but coming to the forefront in terms of prevalence among children in developed countries, as well as the features of their identification are presented. The difficulties in the organization of psychological and pedagogical assessments of children with congenital dual sensory impairment and the interpretation of their results are considered. The conclusion about the importance of the functional approach in the assessment of sensory functions in children with congenital complex disabilities is formulated.</p>

An analysis of visual functioning and cerebral visual impairments in children with profound intellectual and multiple disabilities

The aim of this study was to gain insight into the visual functioning of children with profound intellectuual and multiple disabilities (PIMD). A mixed methods study was performed, determining cross-sectional quantitative ophthalmological/orthoptic data, and qualitative observational data with a standardized research protocol (SRP) of 73 children with PIMD. Descriptive statistics and correlations were used for analyses of the data. Using ophthalmological data, 90.4% of the participants were found visually impaired. Based on the visual acuity (VA) testing, 49.6% of the participants had an impaired VA (<0.3), and 15.3% could not be tested. Applying the SRP, profound cerebral visual impairment (CVI) was found in 43.8% of the participants; severe CVI in 28.8%; mild CVI in 13.7%; and no CVI in 12.3%. The correlation (Spearman’s rho) between CVI and severity of motor impairments was 0.61 ( p= .01). The results showed that visual impairment (VI) based on medical and ophthalmological data was present in nearly all of the participants with the highest prevalence among those with severe motor impairments. Providing specific information about visual functioning and the characteristics of CVI, using the SRP, may contribute to the individually adapted support of the development and partcipation of children with PIMD.

Raising awareness of Cerebral Visual Impairment (CVI) through the use of educational videos: One size does not fit all

Cerebral visual impairment (CVI) is a leading cause of childhood visual impairment in Western countries. This complex condition impacts affected children’s ability to see and process visual information, affecting their learning and development. Although early intervention is beneficial, many children with CVI live with this condition without this being identified. This is, in part, due to unfamiliarity with the condition among health care and education professionals. In recent years, more information has become available, and attempts have been made to explain this condition in accessible formats, such as educational videos. For this study, students and professionals in health care and education were asked to rate their knowledge about CVI, to watch three short educational videos about CVI, and to complete a survey about the use of these videos as a tool to raise awareness and to increase understanding of the condition. The study shows that educational videos can be used effectively to raise awareness of CVI among educational and health care students and professionals. Furthermore, the study shows that there is a mix of understanding, confidence and learning styles across the key professionals supporting children with CVI. As a result, different videos are effective for different audiences and therefore no one size fits all.

Aberrant White Matter Development in Cerebral Visual Impairment: A Proposed Mechanism for Visual Dysfunction Following Early Brain Injury.

Cerebral visual impairment (CVI) is a common sequala of early brain injury, damage, or malformation and is one of the leading individual causes of visual dysfunction in pediatric populations worldwide. Although patients with CVI are heterogeneous both in terms of underlying etiology and visual behavioural manifestations, there may be underlying similarities in terms of which white matter pathways are potentially altered. This exploratory study used diffusion tractography to examine potential differences in volume, quantitative anisotropy (QA), as well as mean, axial, and radial diffusivities (mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD), respectively) focusing on the dorsal and ventral visual stream pathways in a cohort of young adults with CVI compared to typically sighted and developing controls. High angular resolution diffusion imaging (HARDI) data were acquired in a sample of 10 individuals with a diagnosis of CVI (mean age = 17.3 years, 2.97 standard deviation (SD), range 14-22 years) and 17 controls (mean age = 19.82 years, 3.34 SD, range 15-25 years). The inferior longitudinal fasciculus (ILF), inferior fronto-occipital fasciculus (IFOF), vertical occipital fasciculus (VOF), and the three divisions of the superior longitudinal fasciculus (SLF I, II, and III) were virtually reconstructed and average tract volume (adjusted for intracranial volume), MD, AD, and RD were compared between CVI and control groups. As a secondary analysis, an analysis of variance (ANOVA) was carried out to investigate potential differences based on etiology (i.e., CVI due to periventricular leukomalacia (CVI-PVL) and CVI due to other causes (CVI-nonPVL)). We observed a large degree of variation within the CVI group, which minimized the overall group differences in tractography outcomes when examining the CVI sample as a unitary group. In our secondary analysis, we observed significant reductions in tract volume in the CVI-PVL group compared to both controls and individuals with CVI due to other causes. We also observed widespread significant increases in QA, MD, and AD in CVI-PVL compared to the control group, with mixed effects in the CVI-nonPVL group. These data provide preliminary evidence for aberrant development of key white matter fasciculi implicated in visual perceptual processing skills, which are often impaired to varying degrees in individuals with CVI. The results also indicate that the severity and extent of the white matter changes may be due in part to the underlying cause of the cerebral visual impairments. Additional analyses will need to be done in a larger sample alongside behavioural testing to fully appreciate the relationships between white matter integrity, visual dysfunction, and associated causes in individuals with CVI.

Reorganization of integration and segregation networks in brain-based visual impairment

Growing evidence suggests that cerebral connectivity changes its network organization by altering modular topology in response to developmental and environmental experience. However, changes in cerebral connectivity associated with visual impairment due to early neurological injury are still not fully understood. Cerebral visual impairment (CVI) is a brain-based visual disorder associated with damage and maldevelopment of retrochiasmal pathways and areas implicated in visual processing. In this study, we used a multimodal imaging approach and connectomic analyses based on structural (voxel-based morphometry; VBM) and resting state functional connectivity (rsfc) to investigate differences in weighted degree and link-level connectivity in individuals with CVI to controls with neurotypical development. We found that participants with CVI showed significantly reduced grey matter volume within the primary visual cortex and intraparietal sulcus (IPS) compared to controls. Participants with CVI also exhibited marked reorganization characterized by increased integration of visual connectivity to somatosensory and multimodal integration areas (dorsal and ventral attention regions) and lower connectivity from visual to limbic and default mode networks. Link-level functional changes in CVI were also associated with key clinical outcomes related to visual function and development. These findings provide early insight into how visual impairment related to early brain injury distinctly reorganizes the functional network architecture of the human brain.

Children with cerebral visual impairment related visual issues in the classroom

Cerebral visual impairment is a high incidence visual issue with a prevalence rate of 3.4% of children in mainstream education (Williams et al., 2021). However, it is still a very unknown condition with very little awareness in the general public (Ravenscroft et al., 2021). The aim of this research was to better understand how CVI related visual issues impact children in the mainstream classroom. Ten parents and eleven classroom teachers of eleven children with CVI related visual issues participated in the research, which used interviews and focus groups to develop a better understanding of the children and to ascertain the effectiveness of a range of strategies that were implemented to support the children throughout the research period. This was shorter than planned due to the COVID pandemic and school lockdowns. The research found that 82% of the children had learning support needs, 100% had emotional support needs, and 91% experienced challenges with social interactions. The CVI education sessions, decluttering, mindfulness, gratitude and calm breaks all helped the children, however the research period was not long enough to assess the overall effectiveness of the strategies and further research is needed in this area.

Comparison of Eye Tracking and Teller Acuity Cards for Visual Acuity Assessment in Pediatric Cortical/Cerebral Visual Impairment

To compare eye tracking and Teller acuity cards (TAC) for assessment of visual acuity in children with cortical, or cerebral, visual impairment (CVI). Reliability and validity study. We recruited 41 children with CVI from a single academic pediatric neuro-ophthalmology clinic. All children performed eye tracking to measure visual acuity, and 26 children completed TAC assessment by a masked examiner. Additionally, 2 pediatric neuro-ophthalmologists graded visual behavior using the 6-level Visual Behavior Scale (VBS). Eye tracking and TAC were performed at baseline and at 1 month. Test-retest reliability of eye tracking and TAC were assessed using the intraclass correlation coefficient (ICC). Eye tracking and TAC visual acuities were correlated with one another and VBS scores using the Spearman correlation coefficient. Test-retest reliability was excellent for eye tracking measurement of visual acuity (ICC = 0.81, P < .0001). For pediatric CVI, TAC test-retest reliability was fair (ICC = 0.42, P = .04). There was a moderate correlation between eye tracking and TAC (r = 0.43, P = .03) and between TAC and VBS score (r = 0.50, P = .009), and a strong correlation between eye tracking grating acuity and VBS score (r = 0.72, P < .0001). In our cohort of children with CVI, grating acuity measured by eye tracking demonstrated higher test-retest reliability and stronger correlation with pediatric neuro-ophthalmologic assessment of visual behavior than Teller acuity. Objective determination of gaze direction by an eye tracking camera may be more accurate than human assessment in this population. Future research is needed to determine the optimal methods of longitudinal assessment of visual function and functional vision in children with CVI.

Ocular manifestations in Koolen–de Vries syndrome: an international study

ObjectivesKoolen–de Vries Syndrome (KdVS) is a rare multisystem neurodevelopmental disorder. Ocular manifestations, including strabismus, ptosis, and hyperopia, have been reported in KdVS patients, but detailed clinical data are limited. This study aims to investigate the already known ocular malformations and their frequency while uncovering novel ocular associations. MethodsThis was an international cross-sectional study. An anonymous questionnaire was sent to 237 KdVS patients registered in the GenIDA database. The questionnaire inquired about demographic data, ocular symptoms, findings reported by ophthalmologists, and ophthalmologic surgical interventions. The main outcome measures included ocular findings and surgical interventions. ResultsSixty-seven respondents worldwide completed the questionnaire, most (n = 53; 79%) under 18 years of age. Ophthalmologic abnormalities, noted in 79% of patients, included refractive errors (n = 35; 52.2%), strabismus (n = 23; 34.3%), amblyopia (n = 13; 19.5%), and eyelid ptosis (n = 9; 13.4%). Lacrimal disorders were present (n = 6; 9.0%), as were retinal findings (n = 7; 10.4%), including retinal hyperpigmentation or hypopigmentation (n = 4; 7.5%), Sjögren's pigment epithelial reticular dystrophy (n = 1; 1.5%), and macular chorioretinal coloboma (n = 1; 1.5%). Other manifestations included ocular surface disorders (n = 5; 7.5%), cataracts (n = 3; 4.5%), Brown syndrome (n = 1; 1.5%), glaucoma (n = 1; 1.5%), cerebral visual impairment (n = 1; 1.5%), and optic atrophy (n = 1; 1.5%). Fourteen patients (20.8%) had undergone surgical interventions. ConclusionsKdVS is associated with various ophthalmic findings, such as amblyopia, refractive errors, strabismus, and eyelid ptosis. We describe, for the first time, a high rate of nasolacrimal disorders and retinal abnormalities consisting mainly of pigmentary findings, including a rare case of Sjögren's pigment epithelial reticular dystrophy. A comprehensive ophthalmic evaluation is therefore recommended for all KdVS patients at initial diagnosis or at 4–6 months of age for diagnosed newborns.

Ophthalmic manifestations in children with tuberous sclerosis complex.

To report on the ophthalmic findings in children with tuberous sclerosis complex (TSC) in southern Sweden, and to investigate the frequency of refractive errors, strabismus and cerebral visual impairment associated with this condition. This was a retrospective cohort study including all paediatric patients with TSC in southern Sweden born between 1983 and 2020. Medical records were reviewed regarding retinal findings, visual acuity, refractive error, strabismus, full-field electroretinography results and cerebral visual impairment. Ophthalmological records were available for 50 of the 52 children in the region diagnosed with TSC. The mean age at the last visit was 12.4 (SD 7.2) years. Monocular visual acuity had been measured in 38 patients, and the median value did not deviate from that expected for their age in the better eye, but by -0.2 Snellen decimal acuity in the worse eye. Refractive errors were found in 62% of the patients, and strabismus in 16%. Retinal astrocytic hamartomas were found in 34% and achromatic patches in 34%. Ten of the patients on medication with vigabatrin were examined with full-field electroretinography and treatment had to be stopped or loweredin three (30%), due to a reduced response. Investigation of cerebral visual impairment had not been conducted in any of the children. Refractive errors and strabismus were common among children with TSC. None of the patients in this cohort had undergone investigation for cerebral visual impairment. The general awareness of cerebral visual impairment among ophthalmologists is poor and constitutes an important area for improvement.

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

BackgroundThe 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. MethodsThirty 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. ResultsRates 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. ConclusionsIt 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.

Evaluating the Quantity and Quality of Health Economic Literature in Blinding Childhood Disorders: A Systematic Literature Review.

Evidence on the socioeconomic burden associated with childhood visual impairment, severe visual impairment and blindness (VI/SVI/BL) is needed to inform economic evaluations of existing and emerging interventions aimed at protecting or improving vision. This study aimed to evaluate the quantity and quality of literature on resource use and/or costs associated with childhood VI/SVI/BL disorders. PubMed, Web of Science (Ovid), the National Health Service (NHS) Economic Evaluation Database and grey literature were searched in November 2020. The PubMed search was rerun in February 2022. Original articles reporting unique estimates of resource use or cost data on conditions resulting in bilateral VI/SVI/BL were eligible for data extraction. Quality assessment (QA) was undertaken using the Drummond checklist adapted for cost-of-illness (COI) studies. We identified 31 eligible articles, 27 from the peer-reviewed literature and four from the grey literature. Two reported on resource use, and 29 reported on costs. Cerebral visual impairment and optic nerve disorders were not examined in any included studies, whereas retinopathy of prematurity was the most frequently examined condition. The quality of studies varied, with economic evaluations having higher mean QA scores (82%) compared to COI studies (77%). Deficiencies in reporting were seen, particularly in the clinical definitions of conditions in economic evaluations and a lack of discounting and sensitivity analyses in COI studies. There is sparse literature on resource use or costs associated with childhood visual impairment disorders. The first step in addressing this important evidence gap is to ensure core visual impairment outcomes are measured in future randomised control trials of interventions as well as cohort studies and are reported as a discrete health outcome.

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

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