ANDERS ZIENNeurovisual disorders in children

CVI

Patricia Delbeke18-02-2019

WHAT ?

• CVI = Cerebral Visual Impairment

• Disorder in the visual system without structural ocular abnormalities

• Brain problem: disturbance of higher order visual functioning

WHERE IS WALLY ?

WHERE IS THE CHOCO ?

Occipital lobes

• Break up information

• ~ Post Office :• Movement

• Colour

• Contrast

• Vision Acuity

• Visual Field

Visual Fields

• Right Visual Field => Left Visual Cortex

• Left => Right

LR

Cystic Encephalomalacia F-T-P Left Right hemianopsia

2 functional streams

• Ventral stream• Temporal lobes

• Dorsal stream• Posterior parietal lobes

• Motor cortex

• Frontal lobes

• Conscious vision

Ventral stream “What” area

• Temporal lobes • Right Face recognition / Route finding

• Left Object & Words recognition

• “Visual library”

Dorsal stream “Where” area

• Posterior parietal lobes:• to be aware of the whole visual scene & to select out

• Motor cortex• visually-guided movements

• to take a book / to lift the feet

• Frontal lobes :• work strategy : to make choices

• eye movements

ACTION

PLANNING

Interconnections - Bidirectional

Cerebral Visual Impairment = CVI

• Visual disturbance on account of • Oculomotor incoordination and

• Visual perceptual impairment

Pathology of the visual cortices and their interconnecting pathways

• Heterogeneity of expression• Complexity of visual processing

• Children (≠ adults)• Early-onset damage brain is followed by brain growth and development

• Diffuse damage

• Brain plasticity : Training => alters visual outcome

• CVI can improve over time

CVI : causes

• Hypoxic-ischemic encephalopathy 65%

• CNS malformations 12%

• Metabolic and neurodegenerative D 10%

• Hydrocephalus 3%

• CNS infections 3%

• Epilepsy 2%

• Neoplasia 2%

• Traumata 3%

Journal of Child Neurology March 2007

Ischemic damage : premature infant

• ↓ Perfusion of the brain

• Focal necrosis

• Periventricular white matter = watershed vascular supply

• Periventricular leucomalacia

• CP and CVI

PVL and Papil atrophy

• Retrograde transsynaptic degeneration• Axonal loss

Papil : Pallor and cupping

Damage ventral stream (Temporal Left)

• Visual agnosia : • Shape and objects

• Letters : reading disorder

• ~ Right hemianopia

Damage ventral stream (Temporal Right)

• Face recognition (Prosopagnosia)

• Facial expression

• Orientation (Topographic agnosia)

• ~ Left hemianopia

Damage dorsal stream

• Simultaneous perception• To much information

• “Crowding”

• Depth-interpretation

• Visual guidance of movement

• Strabismus - Nystagmus

• ~ lower VF defect

Diagnose CVI in children < 3 yrs old

• ‘Observation’

• Variable, poor, short response to visual stimuli

• Preference for looking at light

• Difficulties to look and handle

• Color preference

• Better visual performance with movement

CVI bilan in children > 3-4 yrs old

• Multidisciplinary• Ophthalmologist

• Anamnesis – Questionnaire / complete ocular examination

• Orthoptist / Psychologist• Orthoptic evaluation / Visual-perceptual tests / IQ test

• Neuropediatrician• Developmental examination

• Neuroimaging

• Co-working with COS – Revalidation Centra – CPRC – Home Guidance

Case 1 Elle 5 yrs old

• > COS : suspicious of CVI• Difficulty selecting a toy in a box DS - too complex visual scene

• Tripping over obstacles DS - impaired visually guided movement

• Getting lost when furniture is moved VS - impaired orientation

• 3th nursery class - GON type 4

• Atcd : • Premature GA 28 Wks

• Perinatal cerebral hemorrhage Left with hydrocephalus

• CP right-sided

1/ MRI brain

• Loss of volume of white matter periventricular

R L R L

Axial Coronal

2/ Ophthalmological examinationOphthalmologist & Orthoptist

• Microstrabismus - No stereo

• Suboptimal vision : 0,6 BE with +3 D

• No VF defects

• Fundus :

3/ IQ testing Psychologist

• WPPSI-III NL T 104 V 108 P 95

• Block design• Spatial visualization

• Motor skill

4/ Visual-Perceptual examinationOrthoptist - Psychologist

• In-Zicht : screeningstool to observe the visual skills

Fag foto KS fotopicnic foto

“busy” background Visual spatial perception Viewing strategy

example result

• L94 Visual perceptual battery• Object Recognition test

• Visual information is presented in a complex manner

<- Overlapping line drawings

<- Unconventional object views

Score < Pc 3

Conclusion

• Visual-perceptual problems

• Dammage visual pathways and associated visual areas => CVI

• Tips and Tricks• Continuation of GOn • Training viewing strategy• Visual comfort

• in front of the class, use finger-ruler, structured working sheets• Home Guidance: advice family - learn to cycle

As ophthalmologist : always exclude ocular pathology

• Refraction errors ? • Myopie – Hypermetropia – Astigmatism

• Accomodation problems for reading ? • Readingglasses

• Cataract ? Retinal disorders ?

Case 2 Amin 7 yrs old

• Part of a twin

• Neurosensorial hearing loss - Cochlear Implant

• ASS

• Difficulties to cath a ball

• Needs light to see better

• Suspicious of visual-perceptual problems : CVI ?

Fundus

Concentric VF defect Nightblindness

Usher Syndrome – No CVI

Case 3 Stan 8 yrs old

• > Independent care and counseling centre : suspicious of CVI

• 2nd primary school – GOn type 4

• DCD with dysgraphia

• T IQ 98 “discrepancy” V IQ 108 P IQ 88

1/ MRI Brain

• Prominent enlargement of “perivascular” Virchow Robin spaces• Developmental brain disorder

BumpingFluctuations in visionCatching a ballReading the clock – timeline…

2/ Questionnaire

=> Negative score

3/ Ophthalmological examinationOphthalmologist & Orthoptist

• Nl Vision : 1,0 BE • BUT :

Incapable to switch • matching-paper <> optotypes

• desk <> blackboard

• Ocular motility• No dissociation between head and eyes• Synkinesias

• Mouth movements • Frowning

3/ Visual-Perceptual examinationOrthoptist - Psychologist

• DEM test (Developmental Eye Movement) In-Zicht

horizontal lines < Pc 1vertical lines Pc 90

• DTVP-2 (Developmental Test of Visual Perception)

visual perception : normal visual-motor integration : low

Conclusion

• Discrepancy IQ – Abnormal MRI – features of CVI• No CVI

• DCD with visual-motor problems

• Tips and tricks • Training gaze movements far<>close

• Training viewing strategy

• Structured work sheets

• Typ 10

Case 4 Quinten 12 yrs old

• Autism

• 2 strokes – interval 10 days – cause ?

• Occlusion both aa cerebri post

Ischemia occipital lobesR > L

Ischemia R cerebellum

Cortical blindnessVA < 0,05No colour perception

• Center for Visual Revalidation• Digital working – dactylo

• Software Supernova : magnifier and screen reader

• Bednet

• Visual perceptual problems ?

1/ Ophthalmological examinationOphthalmologist & Orthoptist

• Vision : 1,0 BE

• Nl colour

• Goldmann VF : Le Hemianopia

• Torticollis headturn to the Left

2/ IQ testing Psychologist

• WISC-V-NL• TIQ: 89, below average

• Verbal Comprehension: Q 116, above average

• Processing Speed: Q 45, very weak

3/ Visual-Perceptual examinationOrthoptist - Psychologist

Motivated boy +++

• DEM-test < Pc1 : severe problems with scanning

• DTVP-test < PC1

• In-Zicht : crowding – complex designs – time consuming

Conclusion

• CVI - hemianopia

• Tips and trics• Type 9 with CVI approach – Home Guidance

• Preferred seating in the classroom, left

• He needs• Extra time to look at material

• Less visual complexity (classroom, working sheets)

• Vision breaks

Thank you