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Collart L, Ortibus E, Ben Itzhak N. An evaluation of health-related quality of life and its relation with functional vision in children with cerebral visual impairment. RESEARCH IN DEVELOPMENTAL DISABILITIES 2024; 154:104861. [PMID: 39461247 DOI: 10.1016/j.ridd.2024.104861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2024] [Revised: 09/24/2024] [Accepted: 10/15/2024] [Indexed: 10/29/2024]
Abstract
BACKGROUND Health-related Quality of Life (HRQOL) and its relation with functional vision is understudied in cerebral visual impairment (CVI). AIMS Characterising HRQOL, comparing child self- and parent proxy-reports, and exploring relations with functional vision. METHODS AND PROCEDURES Seventy-three children with CVI (n females = 33; n males = 40; Mean performance age = 7y2m) were included. HRQOL was measured with Pediatric Quality of Life Inventory (PedsQL) child self- and parent proxy-reports and compared using Wilcoxon signed-rank tests. Risk for impaired HRQOL was evaluated using cut-off scores. Parents scored functional vision using the Insight Questions Inventory and the Flemish CVI Questionnaire. OUTCOMES AND RESULTS 61 % (self-reported) or 66 % of children (proxy-reported) were at-risk for impaired total HRQOL. Ratings were correlated (rs = 0.305; p = 0.013); however, children rated higher total HRQOL compared to parent-proxy (r = 0.382; p = 0.002). The Insight Questions Inventory and the PedsQL proxy-report were correlated (rp = -0.454; p < 0.001), the Flemish CVI Questionnaire was negligibly correlated (rp = -0.244; p = 0.041). CONCLUSIONS AND IMPLICATIONS HRQOL is reduced in CVI, and both child and parent perspectives are crucial. HRQOL and functional vision are intricately related, and impairment in one negatively affects the other.
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Affiliation(s)
- L Collart
- Faculty of Medicine, University of Leuven (KU Leuven), Leuven, Belgium
| | - E Ortibus
- Department of Development and Regeneration, University of Leuven (KU Leuven), Leuven, Belgium; KU Leuven Child and Youth Institute (L-C&Y), Leuven, Belgium.
| | - N Ben Itzhak
- Department of Development and Regeneration, University of Leuven (KU Leuven), Leuven, Belgium; KU Leuven Child and Youth Institute (L-C&Y), Leuven, Belgium
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2
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Hokken MJ, Stein N, Pereira RR, Rours IGIJG, Frens MA, van der Steen J, Pel JJM, Kooiker MJG. Eyes on CVI: Eye movements unveil distinct visual search patterns in Cerebral Visual Impairment compared to ADHD, dyslexia, and neurotypical children. RESEARCH IN DEVELOPMENTAL DISABILITIES 2024; 151:104767. [PMID: 38861794 DOI: 10.1016/j.ridd.2024.104767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 05/10/2024] [Accepted: 05/22/2024] [Indexed: 06/13/2024]
Abstract
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.
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Affiliation(s)
- Marinke J Hokken
- Erasmus MC, department of Neuroscience, Molewaterplein 40, 3015 GD Rotterdam, the Netherlands; Royal Dutch Visio, Amersfoorstestraatweg 180, 1272 RR Huizen, the Netherlands.
| | - Niklas Stein
- University of Münster, Insitute of Psychology, Fliednerstr. 21, 48149 Münster, NRW, Germany
| | - Rob Rodrigues Pereira
- Medical Centre Kinderplein, Rotterdam, Metroplein 88, 3083 BB Rotterdam, the Netherlands
| | - Ingrid G I J G Rours
- Medical Centre Kinderplein, Rotterdam, Metroplein 88, 3083 BB Rotterdam, the Netherlands
| | - Maarten A Frens
- Erasmus MC, department of Neuroscience, Molewaterplein 40, 3015 GD Rotterdam, the Netherlands
| | - Johannes van der Steen
- Erasmus MC, department of Neuroscience, Molewaterplein 40, 3015 GD Rotterdam, the Netherlands
| | - Johan J M Pel
- Erasmus MC, department of Neuroscience, Molewaterplein 40, 3015 GD Rotterdam, the Netherlands
| | - Marlou J G Kooiker
- Erasmus MC, department of Neuroscience, Molewaterplein 40, 3015 GD Rotterdam, the Netherlands; Royal Dutch Visio, Amersfoorstestraatweg 180, 1272 RR Huizen, the Netherlands
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3
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Mooney SW, Alam NM, Sciarabba MJ, Sheldon KR, Prusky GT. Quantitative patterns of visual impairment and recovery in children with brain injury. RESEARCH SQUARE 2024:rs.3.rs-4511323. [PMID: 39149459 PMCID: PMC11326396 DOI: 10.21203/rs.3.rs-4511323/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/17/2024]
Abstract
Brain injury can cause many distinct types of visual impairment in children, but these deficits are difficult to quantify due to co-morbid deficits in communication and cognition. Clinicians must instead rely on low-resolution, subjective judgements of simple reactions to handheld stimuli, which limits treatment potential. We have developed an interactive assessment program called the Visual Ladder, which uses gaze-based responses to intuitive, game-like tasks to address the lack of broad-spectrum quantified data on the visual abilities of children with brain injury. Here, we present detailed metrics on eye movements, field asymmetries, contrast sensitivity, and other critical visual abilities measured longitudinally using the Ladder in hospitalized children with varying types and degrees of brain injury, many of whom were previously considered untestable. Our findings show which abilities are most likely to exhibit recovery and reveal how distinct patterns of task outcomes defined unique diagnostic clusters of visual impairment.
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Affiliation(s)
- Scott W.J. Mooney
- Burke Neurological Institute, White Plains, NY, USA
- Blythedale Children’s Hospital, Valhalla, NY, USA
- Weill Cornell Medicine, New York, NY, USA
| | - Nazia M. Alam
- Burke Neurological Institute, White Plains, NY, USA
- Blythedale Children’s Hospital, Valhalla, NY, USA
| | | | | | - Glen T. Prusky
- Burke Neurological Institute, White Plains, NY, USA
- Blythedale Children’s Hospital, Valhalla, NY, USA
- Weill Cornell Medicine, New York, NY, USA
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4
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Pamir Z, Manley CE, Bauer CM, Bex PJ, Dilks DD, Merabet LB. Visuospatial processing in early brain-based visual impairment is associated with differential recruitment of dorsal and ventral visual streams. Cereb Cortex 2024; 34:bhae203. [PMID: 38795357 PMCID: PMC11484488 DOI: 10.1093/cercor/bhae203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 04/25/2024] [Indexed: 05/27/2024] Open
Abstract
Visuospatial processing impairments are prevalent in individuals with cerebral visual impairment (CVI) and are typically ascribed to "dorsal stream dysfunction" (DSD). However, the contribution of other cortical regions, including early visual cortex (EVC), frontal cortex, or the ventral visual stream, to such impairments remains unknown. Thus, here, we examined fMRI activity in these regions, while individuals with CVI (and neurotypicals) performed a visual search task within a dynamic naturalistic scene. First, behavioral performance was measured with eye tracking. Participants were instructed to search and follow a walking human target. CVI participants took significantly longer to find the target, and their eye gaze patterns were less accurate and less precise. Second, we used the same task in the MRI scanner. Along the dorsal stream, activation was reduced in CVI participants, consistent with the proposed DSD in CVI. Intriguingly, however, visual areas along the ventral stream showed the complete opposite pattern, with greater activation in CVI participants. In contrast, we found no differences in either EVC or frontal cortex between groups. These results suggest that the impaired visuospatial processing abilities in CVI are associated with differential recruitment of the dorsal and ventral visual streams, likely resulting from impaired selective attention.
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Affiliation(s)
- Zahide Pamir
- Department of Psychology & Department of Neuroscience, Bilkent University, Üniversiteler, Çankaya/Ankara 06800, Turkey
- Aysel Sabuncu Brain Research Center, Bilkent University, Üniversiteler, Çankaya/Ankara 06800, Turkey
| | - Claire E Manley
- The Laboratory for Visual Neuroplasticity, Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, 20 Staniford Street, Boston, MA 02114, USA
| | - Corinna M Bauer
- Lab for Neuroimaging and Vision Science, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 125 Nashua St. Suite 660, Boston, MA 02114, USA
| | - Peter J Bex
- The Translational Vision Laboratory, Department of Psychology, Northeastern University, 105-107 Forsyth St #125, Boston, MA 02115, USA
| | - Daniel D Dilks
- Department of Psychology, Emory University, 36 Eagle Row, Atlanta, GA 30322, USA
| | - Lotfi B Merabet
- The Laboratory for Visual Neuroplasticity, Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, 20 Staniford Street, Boston, MA 02114, USA
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Hokken MJ, van der Zee YJ, van der Geest JN, Kooiker MJG. Parent-reported problems in children with Cerebral Visual Impairment: Improving the discriminative ability from ADHD and dyslexia using screening inventories. Neuropsychol Rehabil 2024:1-21. [PMID: 38502713 DOI: 10.1080/09602011.2024.2328875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 03/02/2024] [Indexed: 03/21/2024]
Abstract
Daily problems of children with Cerebral Visual Impairment (CVI) are often misinterpreted as symptoms of behavioural disorders or learning disabilities instead of higher order visual function (HOVF) deficits. It is difficult to differentiate between various paediatric clinical groups based on daily manifestations. We used two CVI inventories (V-CVI-I, HVFQI) and an ADHD questionnaire (AVL) to compare parent-reported visual and behavioural problems of children with CVI, ADHD, dyslexia and neurotypical children (Age 6-15, Verbal Intelligence > 70). Our results show a higher percentage of parent-reported visual problems in children with CVI compared to all other groups, which was not affected by their visual acuity levels. On most HOVF categories, a higher percentage of parent-reported visual problems was also found in children with ADHD or dyslexia compared to neurotypical children. Children with ADHD had significantly more parent-reported behavioural problems, but more behavioural problems were reported by the parents of children with CVI compared to neurotypical children as well. Our findings complicate using the existing inventories for initial screening and referral of children with potential CVI. We propose a shortened screening list to improve the potential differentiation between CVI and ADHD or dyslexia based on parent-reported visual problems in everyday life.
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Affiliation(s)
- Marinke J Hokken
- Erasmus MC, Department of Neuroscience, Rotterdam, the Netherlands
- Royal Dutch Visio, Huizen, the Netherlands
| | | | | | - Marlou J G Kooiker
- Erasmus MC, Department of Neuroscience, Rotterdam, the Netherlands
- Royal Dutch Visio, Huizen, the Netherlands
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Walter K, Manley CE, Bex PJ, Merabet LB. Visual search patterns during exploration of naturalistic scenes are driven by saliency cues in individuals with cerebral visual impairment. Sci Rep 2024; 14:3074. [PMID: 38321069 PMCID: PMC10847433 DOI: 10.1038/s41598-024-53642-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Accepted: 02/03/2024] [Indexed: 02/08/2024] Open
Abstract
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.
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Affiliation(s)
- Kerri Walter
- Translational Vision Lab, Department of Psychology, Northeastern University, Boston, MA, USA
| | - Claire E Manley
- The Laboratory for Visual Neuroplasticity, Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, 20 Staniford Street, Boston, MA, 02114, USA
| | - Peter J Bex
- Translational Vision Lab, Department of Psychology, Northeastern University, Boston, MA, USA
| | - Lotfi B Merabet
- The Laboratory for Visual Neuroplasticity, Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, 20 Staniford Street, Boston, MA, 02114, USA.
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Silveira S, Kelly N, Wright R. Australian children with cerebral visual impairment: using what we know now to improve future approaches. Strabismus 2023; 31:253-261. [PMID: 37997430 DOI: 10.1080/09273972.2023.2272675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2023]
Abstract
PURPOSE Little has been reported on Australian children with Cerebral Vision Impairment (CVI). This paper aims to present the outcome of an audit focussed on children with the primary diagnosis of CVI, using findings from the Australian Childhood Vision Impairment Register (ACVIR). METHODS Records on 132 children (49% girls, 51% boys) from ACVIR data gathered from both the child's parent/guardian and their eye health professional were reviewed. The child's demographics, level of vision impairment, birth history, diagnostic journey, secondary ocular diagnoses, comorbidities and low vision support were analyzed. Several correlations were investigated using a Kendall's tau-b analysis including the relationship between vision and age of diagnosis; level of vision and developmental delay; and age of suspicion of visual impairment and age of diagnosis. RESULTS The most common level of visual impairment was blindness (39%), and most children were suspected and diagnosed of visual impairment in the first 6 months of life. The majority of children were born full term (72%), weighing >2000gms (84%). Nearly half of the cohort of children (48%) had a secondary ocular diagnosis with 44% having nystagmus. The majority of children (80%) had additional health problems, and 85% of children had additional disabilities, with 79% having developmental delay. CONCLUSION While the findings of this audit cannot be generalized to a wider population of Australian children with CVI, the outcome encourages continued discussion on CVI, to explore comprehensive assessment approaches which facilitate timely and accurate diagnosis.
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Affiliation(s)
- Susan Silveira
- NextSense, NextSense Institute, North Rocks, NSW
- Macquarie School of Education, Faculty of Arts, Macquarie University, Macquarie Park, NSW
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McDowell N, Butler P. Validation of the Austin Assessment: A screening tool for cerebral visual impairment related visual issues. PLoS One 2023; 18:e0293904. [PMID: 37917596 PMCID: PMC10621811 DOI: 10.1371/journal.pone.0293904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Accepted: 10/21/2023] [Indexed: 11/04/2023] Open
Abstract
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.
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Affiliation(s)
- Nicola McDowell
- Institute of Education, Massey University, Auckland, New Zealand
| | - Philippa Butler
- Institute of Education, Massey University, Auckland, New Zealand
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Philip J, Huurneman B, Jansonius NM, Cillessen AHN, Boonstra FN. Childhood cerebral visual impairment subtype classification based on an extensive versus a limited test battery. Front Neurosci 2023; 17:1266201. [PMID: 37954874 PMCID: PMC10637406 DOI: 10.3389/fnins.2023.1266201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 10/06/2023] [Indexed: 11/14/2023] Open
Abstract
Purpose To classify CVI subtypes and compare the added value of an extensive test battery over a limited test battery in subtype classification of cerebral visual impairment (CVI) in children. Methods Seventy-five children with a clinical diagnosis of CVI (median [IQR] age: 9 [7-12] years) were identified from the medical records. The extensive test battery included visual acuity, contrast sensitivity, ocular alignment, eye movement analysis, visual field analysis, optic nerve head evaluation, and evaluation of visual perception. The limited test battery included visual acuity, contrast sensitivity, ocular alignment, and evaluation of visual perception. Principal component analysis (PCA) followed by cluster analysis was done, for both test batteries separately, to determine the optimum subtype classification for CVI. Results Fifty-one participants with an extensive test battery with mild to moderate visual impairment were included in the main analysis. This resulted in four CVI subtypes for the extensive test battery (subtle characteristics, higher-level visual function deficits, lower-level visual function deficits, and higher- and lower- level visual function deficits) and three CVI subtypes for the limited test battery (subtle characteristics, higher-level visual function deficits, and higher- and lower- level visual function deficits). There were significant differences between the subtypes for 9 out of 10 measures of the extensive and all 4 measures of the limited test battery (p < 0.05). The subtle characteristics subtype (extensive n = 19, limited n = 15) showed near normal lower and higher-level visual functions in both test batteries. The higher-level visual function deficits subtype (extensive n = 18, limited n = 24) showed near normal visual acuity combined with significant visual perceptual deficits in both test batteries; accompanied by visual pathways defects and abnormal eye movement behavior in the extensive test battery. The higher- and lower- level visual function deficits subtype (extensive n = 4, limited n = 12) showed both higher and lower-level visual function deficits in both test batteries, but application of the extensive test battery revealed additional visual pathways defects and abnormal eye movement behavior. The lower-level visual function deficits CVI subtype (extensive n = 10) was a new subtype identified by the extensive test battery. This subtype showed lower-level visual function deficits together with abnormal eye movement measures. Conclusion This data-driven study has provided meaningful CVI subtype classifications based on the outcomes of various key functional and structural measures in CVI diagnosis. Comparison of the extensive test battery to the limited test battery revealed the added value of an extensive test battery in classifying CVI. The outcomes of this study, therefore, have provided a new direction in the area of CVI classification.
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Affiliation(s)
- Jannet Philip
- Royal Dutch Visio, National Foundation for the Visually Impaired and Blind, Huizen, Netherlands
- Behavioural Science Institute, Radboud University, Nijmegen, Netherlands
| | - Bianca Huurneman
- Royal Dutch Visio, National Foundation for the Visually Impaired and Blind, Huizen, Netherlands
- Department of Cognitive Neuroscience, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, Netherlands
| | - Nomdo M. Jansonius
- Department of Ophthalmology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
- Graduate School of Medical Science, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | | | - Frouke N. Boonstra
- Royal Dutch Visio, National Foundation for the Visually Impaired and Blind, Huizen, Netherlands
- Behavioural Science Institute, Radboud University, Nijmegen, Netherlands
- Department of Cognitive Neuroscience, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, Netherlands
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Merabet LB, Manley CE, Pamir Z, Bauer CM, Skerswetat J, Bex PJ. Motion and form coherence processing in individuals with cerebral visual impairment. Dev Med Child Neurol 2023; 65:1379-1386. [PMID: 37012700 PMCID: PMC10795851 DOI: 10.1111/dmcn.15591] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 03/06/2023] [Accepted: 03/08/2023] [Indexed: 04/05/2023]
Abstract
AIM Using a visual psychophysical paradigm, we sought to assess motion and form coherence thresholds as indices of dorsal and ventral visual stream processing respectively, in individuals with cerebral visual impairment (CVI). We also explored potential associations between psychophysical assessments and brain lesion severity in CVI. METHOD Twenty individuals previously diagnosed with CVI (mean age = 17 years 11 months [SD 5 years 10 months]; mean Verbal IQ = 86.42 [SD 35.85]) and 30 individuals with neurotypical development (mean age = 20 years 1 month [SD 3 years 8 months]; mean Verbal IQ = 110.05 [SD 19.34]) participated in the study. In this two-group comparison, cross-sectional study design, global motion, and form pattern coherence thresholds were assessed using a computerized, generalizable, self-administrable, and response-adaptive psychophysical paradigm called FInD (Foraging Interactive D-prime). RESULTS Consistent with dorsal stream dysfunction, mean global motion (but not form) coherence thresholds were significantly higher in individuals with CVI compared to controls. No statistically significant association was found between coherence thresholds and lesion severity. INTERPRETATION These results suggest that the objective assessment of motion and form coherence threshold sensitivities using this psychophysical paradigm may be useful in helping to characterize perceptual deficits and the complex clinical profile of CVI. WHAT THIS PAPER ADDS In participants with cerebral visual impairment (CVI), motion (but not form) coherence thresholds were significantly higher compared to controls. These psychophysical results support the notion of dorsal stream dysfunction in CVI.
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Affiliation(s)
- Lotfi B. Merabet
- The Laboratory for Visual Neuroplasticity, Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Claire E. Manley
- The Laboratory for Visual Neuroplasticity, Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
| | - Zahide Pamir
- The Laboratory for Visual Neuroplasticity, Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA, USA
- Bilkent University, Department of Psychology, Ankara, Turkey
| | - Corinna M. Bauer
- Lab for Neuroimaging and Vision Science, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Jan Skerswetat
- Translational Vision Lab, Department of Psychology, Northeastern University, Boston, MA, USA
| | - Peter J. Bex
- Translational Vision Lab, Department of Psychology, Northeastern University, Boston, MA, USA
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11
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Lueck AH, Chokron S, Dutton GN. Commentary: Profiling Children With Cerebral Visual Impairment (CVI) Using Multiple Methods of Assessment to Aid in Differential Diagnosis. Semin Pediatr Neurol 2023; 47:101070. [PMID: 37919040 DOI: 10.1016/j.spen.2023.101070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Accepted: 07/30/2023] [Indexed: 11/04/2023]
Abstract
PROFILING CHILDREN WITH CEREBRAL VISUAL IMPAIRMENT USING MULTIPLE METHODS OF ASSESSMENT TO AID IN DIFFERENTIAL DIAGNOSIS: Amanda H. Lueck , Gordon N. Dutton , Sylvie Chokron Seminars in Pediatric Neurology Volume 31, October 2019, Pages 5-14 Cerebral (cortical) visual impairment (CVI), the primary cause of visual impairment in chil dren in high-income countries, is increasing globally due to improved life-saving measures for premature and full-term infants. Yet the consequences of this condition are only begin ning to be understood and addressed. According to the topography, site, and the extent of the pathology, the deficit may variably concern central visual functions, visual field, percep tion of movement, visual analysis, visual exploration, attention, or visual memory, as well as visual guidance of movement. Each affected child has a unique clinical picture, which needs to be identified and individually profiled. This is probably the underlying reason that CVI is commonly underdiagnosed or misdiagnosed, especially in children, and, as a consequence, the full range of potential behavioral outcomes are not identified and adequately addressed. The present paper shows how the use of multiple methods of assessment can improve understanding of children with CVI.
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Affiliation(s)
- Amanda H Lueck
- Department of Special Education, San Francisco State University, San Francisco, CA.
| | - Sylvie Chokron
- Integrative Neuroscience and Cognitive Center, CNRS, UMR 8002, Paris, France; Institut de Neuropsychologie, Neurovision & Neurocognition, Hôpital Fondation Adolphe de Rothschild, Paris, France
| | - Gordon N Dutton
- Department of Optometry and Visual Science, Glasgow Caledonian University, Glasgow, United Kingdom
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Lim HW, Pershing S, Moshfeghi DM, Heo H, Haque ME, Lambert SR. Causes of Childhood Blindness in the United States Using the IRIS® Registry (Intelligent Research in Sight). Ophthalmology 2023; 130:907-913. [PMID: 37037315 PMCID: PMC10524509 DOI: 10.1016/j.ophtha.2023.04.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 03/27/2023] [Accepted: 04/03/2023] [Indexed: 04/12/2023] Open
Abstract
PURPOSE To investigate causes of childhood blindness in the United States using the IRIS® Registry (Intelligent Research in Sight). DESIGN Cross-sectional study. PARTICIPANTS Patients ≤ 18 years of age with visual acuity (VA) 20/200 or worse in their better-seeing eye in the IRIS Registry during 2018. METHODS Causes of blindness were classified by anatomic site and specific diagnoses. MAIN OUTCOME MEASURES Percentages of causes of blindness. RESULTS Of 81 164 children with 2018 VA data in the IRIS Registry, 961 (1.18%) had VA 20/200 or worse in their better-seeing eye. Leading causes of blindness were retinopathy of prematurity (ROP) in 301 patients (31.3%), nystagmus in 78 patients (8.1%), and cataract in 64 patients (6.7%). The retina was the leading anatomic site (47.7%) followed by optic nerve (11.6%) and lens (10.0%). A total of 52.4% of patients had treatable causes of blindness. CONCLUSIONS This analysis offers a unique cross-sectional view of childhood blindness in the United States using a clinical data registry. More than one-half of blind patients had a treatable cause of blindness. FINANCIAL DISCLOSURE(S) Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
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Affiliation(s)
- Han Woong Lim
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA
- Department of Ophthalmology, Hanyang University School of Medicine, Seoul, Republic of Korea
| | - Suzann Pershing
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA
- Ophthalmology and Eye Care Services, VA Palo Alto Health Care System, Palo Alto, CA
| | - Darius M. Moshfeghi
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA
| | - Hwan Heo
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA
- Department of Ophthalmology, Chonnam National University Medical School and Hospital, Gwangju, Republic of Korea
| | - Md Enamul Haque
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA
| | - Scott R. Lambert
- Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA
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13
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Manley CE, Walter K, Micheletti S, Tietjen M, Cantillon E, Fazzi EM, Bex PJ, Merabet LB. Object identification in cerebral visual impairment characterized by gaze behavior and image saliency analysis. Brain Dev 2023; 45:432-444. [PMID: 37188548 PMCID: PMC10524860 DOI: 10.1016/j.braindev.2023.05.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 04/26/2023] [Accepted: 05/01/2023] [Indexed: 05/17/2023]
Abstract
Individuals with cerebral visual impairment (CVI) have difficulties identifying common objects, especially when presented as cartoons or abstract images. In this study, participants were shown a series of images of ten common objects, each from five possible categories ranging from abstract black & white line drawings to color photographs. Fifty individuals with CVI and 50 neurotypical controls verbally identified each object and success rates and reaction times were collected. Visual gaze behavior was recorded using an eye tracker to quantify the extent of visual search area explored and number of fixations. A receiver operating characteristic (ROC) analysis was also carried out to compare the degree of alignment between the distribution of individual eye gaze patterns and image saliency features computed by the graph-based visual saliency (GBVS) model. Compared to controls, CVI participants showed significantly lower success rates and longer reaction times when identifying objects. In the CVI group, success rate improved moving from abstract black & white images to color photographs, suggesting that object form (as defined by outlines and contours) and color are important cues for correct identification. Eye tracking data revealed that the CVI group showed significantly greater visual search areas and number of fixations per image, and the distribution of eye gaze patterns in the CVI group was less aligned with the high saliency features of the image compared to controls. These results have important implications in helping to understand the complex profile of visual perceptual difficulties associated with CVI.
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Affiliation(s)
- Claire E Manley
- The Laboratory for Visual Neuroplasticity, Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, USA
| | - Kerri Walter
- Translational Vision Lab. Department of Psychology, Northeastern University, Boston, MA, USA
| | - Serena Micheletti
- Unit of Child Neurology and Psychiatry, ASST Spedali Civili of Brescia, Brescia, Italy; Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Matthew Tietjen
- The Laboratory for Visual Neuroplasticity, Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, USA
| | - Emily Cantillon
- The Laboratory for Visual Neuroplasticity, Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, USA
| | - Elisa M Fazzi
- Unit of Child Neurology and Psychiatry, ASST Spedali Civili of Brescia, Brescia, Italy; Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Peter J Bex
- Translational Vision Lab. Department of Psychology, Northeastern University, Boston, MA, USA
| | - Lotfi B Merabet
- The Laboratory for Visual Neuroplasticity, Department of Ophthalmology, Massachusetts Eye and Ear, Harvard Medical School, Boston, USA.
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14
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Hemptinne C, Hupin N, Lochy A, Yüksel D, Rossion B. Spatial Resolution Evaluation Based on Experienced Visual Categories With Sweep Evoked Periodic EEG Activity. Invest Ophthalmol Vis Sci 2023; 64:17. [PMID: 36881407 PMCID: PMC10007901 DOI: 10.1167/iovs.64.3.17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Accepted: 02/12/2023] [Indexed: 03/08/2023] Open
Abstract
Purpose Visual function is typically evaluated in clinical settings with visual acuity (VA), a test requiring to behaviorally match or name optotypes such as tumbling E or Snellen letters. The ability to recognize these symbols has little in common with the automatic and rapid visual recognition of socially important stimuli in real life. Here we use sweep visual evoked potentials to assess spatial resolution objectively based on the recognition of human faces and written words. Methods To this end, we tested unfamiliar face individuation1 and visual word recognition2 in 15 normally sighted adult volunteers with a 68-electrode electroencephalogram system. Results Unlike previous measures of low-level visual function including VA, the most sensitive electrode was found at an electrode different from Oz in a majority of participants. Thresholds until which faces and words could be recognized were evaluated at the most sensitive electrode defined individually for each participant. Word recognition thresholds corresponded with the VA level expected from normally sighted participants, and even a VA significantly higher than expected from normally sighted individuals for a few participants. Conclusions Spatial resolution can be evaluated based on high-level stimuli encountered in day-to-day life, such as faces or written words with sweep visual evoked potentials.
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Affiliation(s)
- Coralie Hemptinne
- Institute of Neuroscience, Université catholique de Louvain, Louvain-La-Neuve, Belgium
- Ophthalmology Department, Cliniques Universitaires Saint-Luc, Brussels, Belgium
| | - Nathan Hupin
- Institute of Neuroscience, Université catholique de Louvain, Louvain-La-Neuve, Belgium
- Ophthalmology Department, Cliniques Universitaires Saint-Luc, Brussels, Belgium
| | - Aliette Lochy
- Cognitive Science and Assessment Institute, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Demet Yüksel
- Institute of Neuroscience, Université catholique de Louvain, Louvain-La-Neuve, Belgium
- Ophthalmology Department, Cliniques Universitaires Saint-Luc, Brussels, Belgium
| | - Bruno Rossion
- Institute of Neuroscience, Université catholique de Louvain, Louvain-La-Neuve, Belgium
- University of Lorraine, CNRS, CRAN, Lorraine, France
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Zihl J, Unterberger L, Lippenberger M. Visual and cognitive profiles in children with and without cerebral visual impairment. BRITISH JOURNAL OF VISUAL IMPAIRMENT 2023. [DOI: 10.1177/02646196221149564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Reliable differentiation of visual-perceptual difficulties in children with and without cerebral visual impairment (CVI) can often pose a diagnostic challenge. We, therefore, assessed the visual-perceptual profile in 94 children with and 77 children without suspected CVI between the ages of 8 and 17 years in a non-clinical setting, using a screening questionnaire and standardized visual-perceptual tests. Children with suspected CVI reported more frequently greater visual difficulties, had lower visual acuity, and were significantly impaired in visual search tests, in visual form and object perception, in visual space perception, and in visual text processing. There were no significant differences between groups in stereopsis, fixation stability, motility, horizontal saccadic eye movements, and convergence and accommodation. Cognitive performance in auditory attention and verbal short-term and working memory was similar in both groups. Our results indicate that the use of an appropriate questionnaire and specific visual-perceptual tests enables valid diagnostic detection of CVI. The additional use of cognitive tests also allows differentiation between primary and secondary impairments in visual perception.
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Jimenez-Gomez A, Fisher KS, Zhang KX, Liu C, Sun Q, Shah VS. Longitudinal neurological analysis of moderate and severe pediatric cerebral visual impairment. Front Hum Neurosci 2022; 16:772353. [PMID: 36051970 PMCID: PMC9425457 DOI: 10.3389/fnhum.2022.772353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 06/28/2022] [Indexed: 11/19/2022] Open
Abstract
Introduction Cerebral visual impairment (CVI) results from damage to cerebral visual processing structures. It is the most common cause of pediatric visual impairment in developed countries and rising in prevalence in developing nations. There is currently limited understanding on how neurologic, developmental, and ophthalmic factors predict outcome for pediatric CVI. Method A retrospective manual chart review of pediatric CVI patients seen at the tertiary pediatric hospital neurology and neuro-ophthalmology service between 2010 and 2019 was conducted. Patients were stratified into severity groups (based on a custom CVI grading score), and followed over time to identify outcome predictors. Collected baseline characteristics included perinatal, genetic, developmental, and neurologic history, along with neuroimaging and fundoscopic findings on examination. Longitudinal data collected included age, seizure control, and type of therapy received. Linear mixed-effect models were used for longitudinal CVI grade outcome analysis. Results A total of 249 individuals spanning 779 patient visits were identified. Mean age at diagnosis was 18.8 ± 16.8 months (2–108 months). About 64.3% were born at term age. Perinatal history revealed hypoxic ischemic encephalopathy (HIE) in 16.5%, intraventricular hemorrhage (IVH) in 11.6%, and seizures in 21.7%. At presentation, 60.3% had a diagnosis of cerebral palsy and 84.7% had developmental delay. Among all subjects, 78.6% had epilepsy; 33.8% had an epileptic encephalopathy, with spasms/hypsarrhythmia being most common. Abnormal neuroimaging was present in 93.8%. Genetic anomalies were present in 26.9%. Baseline visual examination revealed no blink-to-light (BTL) in 24.5%; only BTL in 34.5%, fixation/tracking in 26.5%, and optokinetic drum follow in 14.4%. Longitudinal data analysis showed that perinatal history of HIE, a positive epilepsy history, using multiple (≥3) epilepsy medications, cerebral palsy, and abnormal fundoscopic findings were all negatively associated with CVI grade change over time. After controlling for significant confounders, receiving any type of therapy [early childhood intervention (ECI), physical and occupational therapy (PT/OT), refractive error correction or glasses] was significantly associated with longitudinal improvement in CVI grade compared to patients who did not receive any therapy, with glasses yielding the largest benefit. Conclusion This study offers extensive insights into neurologic, developmental and ophthalmologic features in patients with moderate to severe CVI. In concordance with previous findings, aspects of perinatal history and epilepsy/seizure control may help inform severity and prognosis in the general neurology or ophthalmology clinic. Conversely, these aspects, as well as genetic and specific epilepsy traits may alert vision health care providers in the clinic to pursue visual evaluation in at-risk individuals. Longitudinal follow-up of CVI patients showed that interventional therapies demonstrated vision function improvement greater than no therapy and maturational development.
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Affiliation(s)
- Andres Jimenez-Gomez
- Neuroscience Center, Joe DiMaggio Children’s Hospital, Hollywood, FL, United States
| | - Kristen S. Fisher
- Division of Pediatric Neurology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Kevin X. Zhang
- Division of Pediatric Ophthalmology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States
- Medical Scientist Training Program, University of Cincinnati College of Medicine, Cincinnati, OH, United States
| | - Chunyan Liu
- Division of Biostatistics and Epidemiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States
| | - Qin Sun
- Division of Biostatistics and Epidemiology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States
| | - Veeral S. Shah
- Division of Pediatric Neurology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States
- Division of Pediatric Ophthalmology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, United States
- Department of Ophthalmology, University of Cincinnati, Cincinnati, OH, United States
- Baylor College of Medicine, Cullen Eye Institute, Houston, TX, United States
- Department of Ophthalmology, Texas Children’s Hospital, Houston, TX, United States
- *Correspondence: Veeral S. Shah, ;
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A Review on Recent Advances of Cerebral Palsy. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:2622310. [PMID: 35941906 PMCID: PMC9356840 DOI: 10.1155/2022/2622310] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 06/27/2022] [Accepted: 07/02/2022] [Indexed: 12/04/2022]
Abstract
This narrative review summarizes the latest advances in cerebral palsy and identifies where more research is required. Several studies on cerebral palsy were analyzed to generate a general idea of the prevalence of, risk factors associated with, and classification of cerebral palsy (CP). Different classification systems used for the classification of CP on a functional basis were also analyzed. Diagnosis systems used along with the prevention techniques were discussed. State-of-the-art treatment strategies for CP were also analyzed. Statistical distribution was performed based on the selected studies. Prevalence was found to be 2-3/1000 lives; the factors that can be correlated are gestational age and birth weight. The risk factors identified were preconception, prenatal, perinatal, and postnatal categories. According to the evidence, CP is classified into spastic (80%), dyskinetic (15%), and ataxic (5%) forms. Diagnosis approaches were based on clinical investigation and neurological examinations that include magnetic resonance imaging (MRI), biomarkers, and cranial ultrasound. The treatment procedures found were medical and surgical interventions, physiotherapy, occupational therapy, umbilical milking, nanomedicine, and stem cell therapy. Technological advancements in CP were also discussed. CP is the most common neuromotor disability with a prevalence of 2-3/1000 lives. The highest contributing risk factor is prematurity and being underweight. Several preventions and diagnostic techniques like MRI and ultrasound were being used. Treatment like cord blood treatment nanomedicine and stem cell therapy needs to be investigated further in the future to apply in clinical practice. Future studies are indicated in the context of technological advancements among cerebral palsy children.
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Boonstra FN, Bosch DGM, Geldof CJA, Stellingwerf C, Porro G. The Multidisciplinary Guidelines for Diagnosis and Referral in Cerebral Visual Impairment. Front Hum Neurosci 2022; 16:727565. [PMID: 35845239 PMCID: PMC9280621 DOI: 10.3389/fnhum.2022.727565] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 05/05/2022] [Indexed: 11/13/2022] Open
Abstract
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.
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Affiliation(s)
- Frouke N. Boonstra
- Royal Dutch Visio, National Foundation for the Visually Impaired and Blind, Huizen, Netherlands
- Department of Cognitive Neuroscience, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Centre Nijmegen, Nijmegen, Netherlands
- Behavioral Science Institute, Radboud University, Nijmegen, Netherlands
- *Correspondence: Frouke N. Boonstra,
| | | | - Christiaan J. A. Geldof
- Royal Dutch Visio, National Foundation for the Visually Impaired and Blind, Huizen, Netherlands
| | - Catharina Stellingwerf
- Royal Dutch Visio, National Foundation for the Visually Impaired and Blind, Huizen, Netherlands
| | - Giorgio Porro
- Department of Ophthalmology, UMC Utrecht and Amphia Hospital Breda, Breda, Netherlands
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