Functional vision in children with perinatal brain damage

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

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

Interventions for children with cerebral visual impairment: A scoping review

AIM

To examine the nature and scope of the literature on interventions implemented for children with cerebral visual impairment (CVI).

METHOD

Using a scoping review methodology, a systematic search of the literature was conducted using four databases including PubMed, Web of Science, Scopus, and Embase. Titles and abstracts were screened and data were extracted and synthesized from full-text, eligible studies. Twenty-three articles were identified and evaluated using quality criteria.

RESULTS

Twenty-three of the 895 studies were included with children aged between 1 month and 17 years 6 months. Interventions were grouped into six categories including visual stimulation, task/environmental adaptations, vision training, acupuncture, stem cell transplantation, and transcranial electric stimulation. Outcome measures examined changes in visual function, functional vision, and visual processing.

INTERPRETATION

Intervention research for children with CVI is in its infancy. Interventions for children with CVI may be beneficial; however, comparing results is difficult due to inconsistency in outcome measures. Most of the intervention studies had lower-level evidence and included small sample sizes. High-quality studies with larger samples and comparison groups are needed to fully understand which evidence-based interventions are most effective for children with CVI. With the incidence of CVI increasing, further development and validation of intervention methods is imperative.

WHAT THIS PAPER ADDS

Intervention studies for children with cerebral visual impairment (CVI) are sparse. Most intervention studies for children with CVI have low-level evidence with low critical appraisal scores. High-quality, controlled intervention studies are needed to guide families and clinicians toward evidence-based practice.

Early intervention for children at risk of visual processing dysfunctions from 1 year of age: a randomized controlled trial protocol

Background

An increasing number of children are suffering from brain damage-related visual processing dysfunctions (VPD). There is currently a lack of evidence-based intervention methods that can be used early in development. We developed a visual intervention protocol suitable from 1 year of age. The protocol is structured, comprehensive and individually adaptive, and is paired with quantitative outcome assessments. Our aim is to investigate the effectiveness of this first visual intervention program for young children with (a risk of) VPD.

Methods

This is a single-blind, placebo-controlled trial that is embedded within standard clinical care. The study population consists of 100 children born very or extremely preterm (< 30 weeks) at 1 year of corrected age (CA), of whom 50% are expected to have VPD. First, children undergo a visual screening at 1 year CA. If they are classified as being at risk of VPD, they are referred to standard care, which involves an ophthalmic and visual function assessment and a (newly developed) visual intervention program. This program consists of a general protocol (standardized and similar for all children) and a supplement protocol (adapted to the specific needs of the child). Children are randomly allocated to an intervention group (starting upon inclusion at 1 year CA) or a control group (postponed: starting at 2 years CA). The control group will receive a placebo treatment. The effectiveness of early visual intervention will be examined with follow-up visual and neurocognitive assessments after 1 year (upon completion of the direct intervention) and after 2 years (upon completion of the postponed intervention).

Discussion

Through this randomized controlled trial we will establish the effectiveness of a new and early visual intervention program. Combining a general and supplement protocol enables both structured comparisons between participants and groups, and custom habilitation that is tailored to a child’s specific needs. The design ensures that all included children will benefit from participation by advancing the age at which they start receiving an intervention. We expect results to be applicable to the overall population of children with (a risk of) VPD early in life.

Trial registration

Netherlands Trial Register: NTR6952. Registered 19 January 2018.

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

INTRODUCTION

Cerebral Visual Impairment (CVI) is the most common cause of visual impairment in children in the developed world and appears to be more prevalent in children with additional support needs (ASN). There is an urgent need for routine screening for CVI, particularly in children with ASN, however, current screening questionnaires for CVI have limited validation. The aim of this study was to evaluate two screening tools: the Five Questions and the CVI Questionnaire. Additionally, the distribution of CVI across neurodevelopmental disorders is unknown. This too was investigated.

METHODS

An online survey was completed by 535 parents. The survey was advertised via social media, CVI websites and parent email systems of four schools. The survey comprised of the Five Questions, the CVI Questionnaire and additional questions regarding the child's diagnoses. Whether or not a child had a diagnosis of CVI and/or additional neurodevelopmental disorders was based on parental report.

RESULTS

Based on parent reports, both the screening tools accurately screened for CVI diagnoses in children. The Five Questions and the CVI Questionnaire have construct validity (as determined through factor analysis), high internal consistency (as determined by Cronbach's alpha) and convergent validity (as determined by correlation analysis of the raw scores of each questionnaire). This study also highlights that among children with neurodevelopmental disorders, a large proportion have parent-reported CVI (23%-39%) and potential CVI (6.59-22.53%; as identified by the questionnaires).

CONCLUSION

The current study demonstrates that the Five Questions and CVI Questionnaire have good convergent validity, internal consistency and a reliable factor structure and may therefore be suitable as screening tools. The study also highlights that reported or potential CVI is evident in a large proportion of children with neurodevelopmental disorders.

Maturation of Binocular, Monocular Grating Acuity and of the Visual Interocular Difference in the First 2 Years of Life

The sweep visual evoked potential method (sVEP) is a powerful tool for measurement of visual acuity in infants. Despite the applicability and reliability of the technique in measuring visual functions the understanding of sVEP acuity maturation and how interocular difference of acuity develops in early infancy, as well as the availability of normality ranges, are rare in the literature. We measured binocular and monocular sVEPS acuities in 481 healthy infants aged from birth to 24 months without ophthalmological diseases. Binocular sVEP acuity was significantly higher than monocular visual acuities for almost all ages. Maturation of monocular sVEP acuity showed 2 longer critical periods while binocular acuity showed three maturation periods in the same age range. We found a systematic variation of the mean interocular acuity difference (IAD) range according to age from 1.45 cpd at birth to 0.31 cpd at 24 months. An additional contribution was the determination of sVEP acuity norms for the entire age range. We conclude that binocular and monocular sVEP acuities have distinct growth curves reflecting different maturation profiles for each function. Differences in IAD range shorten according to age and they should be considered in using the sVEP acuity measurements for clinical diagnosis as amblyopia.

Childhood Stroke and Vision: A Review of the Literature

OBJECTIVE

Here we review the current literature regarding visual outcome after perinatal and childhood stroke.

BACKGROUND

Visual deficits following stroke in adults are common and have been previously reviewed. Less is known about visual deficits following stroke in neonates and older children. Most of the literature regarding this subject has focused on preterm infants, or on other types of brain injury. This review summarizes the types of visual deficits seen in term infants following perinatal stroke and children following childhood stroke and predictors of outcome. This review suggests areas for future research.

METHODS

We performed Ovid MEDLINE searches regarding visual testing in children, vision after childhood stroke, neuroplasticity of vision, treatment of visual impairment after stroke, and driving safety concerns after stroke.

RESULTS

Visual field defects were the most commonly reported visual deficits after perinatal and childhood stroke. There is a significant lack of literature on this subject, and most is in the form of case reports and case series. Children can experience significant visual morbidity after stroke, and have the potential to show some recovery, but guidelines on assessment and treatment of this population are lacking.

CONCLUSIONS

There were limitations to this study, given the small amount of literature available. Although stroke in children can result in severe visual deficits, most children regain at least a portion of their vision. However, more research is needed regarding visual assessment of this population, long-term visual outcomes, specific predictors of recovery, and treatment options.