cvi – background and assessment part 1
DESCRIPTION
CVI – Background and Assessment Part 1. Heather Brooks, Educational Consultant North Carolina Department of Public Instruction . Today we’ll be discussing . Today we’ll be discussing.... Brains & Eye Balls. Vision. - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/1.jpg)
CVI – Background and Assessment Part 1
Heather Brooks, Educational Consultant
North Carolina Department of Public Instruction
![Page 2: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/2.jpg)
Today we’ll be discussing
Today we’ll bediscussing....Brains & Eye Balls
![Page 3: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/3.jpg)
VisionEye Brain Processing MovementExample: You’re walking along in the park and you see these three bears.
![Page 4: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/4.jpg)
Brain Thinking About Grizzly Bears
![Page 5: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/5.jpg)
Motor Action Taken After Seeing a Grizzly
![Page 6: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/6.jpg)
Quick Review of the Eye:I know you know this
Video: How the Eye Works and the Retinahttps://www.youtube.com/watch?
v=Sqr6LKIR2b8
![Page 7: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/7.jpg)
Brain Structure
Vision is not simply processed in the visual cortex. There are numerous places in the brain responsible for interpretation and reaction to visual stimulus.
![Page 8: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/8.jpg)
Cortical Visual Impairment
• CVI occurs due to damage in the brain. • So let’s talk about brain damage for a minute.
![Page 9: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/9.jpg)
What’s the Cortex?
Cerebral Cortex Cerebrum
![Page 10: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/10.jpg)
Brain Damage
The human brain…Has a limited ability to store glucose or oxygen. It is also encompassed in a hard shell (skull) that
doesn’t allow for much swelling.
![Page 11: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/11.jpg)
Brain Damage – Oxygen, Glucose, & Waste Management
Blood brings with it fresh oxygenand glucose.Blood takes away the waste that builds up in the cells.
Without fresh, oxygen rich blood….cell death occurs.
![Page 12: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/12.jpg)
Brain Damage – 2 Important Terms
• Ischemia – lack of blood supply• Hypoxia – lack of oxygen
THE MOST COMMON CAUSEOF CVI IS HYPOXIC-ISCHEMIC
INJURY.
![Page 13: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/13.jpg)
Examples: Brain Damage
Shunt FailureInfectionsMetabolic DiseaseDrugsMicrobesStrokeTraumaComplications of Cardiac treatment…
![Page 14: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/14.jpg)
Neuralplasticity: Finding a New Path
• The brain can learn to reroute information/find new neural pathways
• Visual recovery is better for younger childrenNeurological Insult in Children• Neurological improvement happens for two or more years
after the injury• Children recover better in the immediate time frame and
improve for longer periods*Important that we not set limits or have a predetermined idea
of what a child can learn or how far a child can progress.*
![Page 15: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/15.jpg)
Just to lighten it up for a moment.
![Page 16: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/16.jpg)
What is CVI?
• Cortical Visual Impairment • No single definition for CVI• Generally speaking, CVI is vision loss due to
damage in the brain• CVI can manifest in different ways, with a wide
range of severity.
Profound Functional Blindness
Idiosyncratic Impact on Vision
Mild Severe
![Page 17: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/17.jpg)
How is CVI diagnosed? • Clinical diagnosis – no specific medical test for
CVI• Normal eye exam – or the eye disorder does
not explain the visual behavior• History of neurological insult• Demonstrate unique visual and behavior
characteristics associated with CVI
![Page 18: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/18.jpg)
Examples of Unique Visual and Behavior Characteristics
• Slow, inefficient, and highly variable visual performance
• Light gazing/Photophobia paradox • Color vision and perception of movement is
often preserved• Look Look Away Reach• Visual Agnosias (inability to recognize)
![Page 19: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/19.jpg)
Prevalence of CVILeading cause of pediatric visual impairment in
the developed world. Because…
Improved survival
Other blindness have decreased
![Page 20: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/20.jpg)
Comorbid Conditions
• Epilepsy • Cerebral palsy• Intellectual disabilities• Hearing loss• Hydrocephalus• Abnormal mental development• Microcephaly• Progressive degenerative disorders• Hypotonia
![Page 21: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/21.jpg)
Lots of Names with Visual Impairment Involving the Brain
Cortical Visual ImpairmentCerebral Visual ImpairmentNeurological Visual ImpairmentDelayed Visual MaturationCortical BlindnessCortical Visual Dysfunction
![Page 22: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/22.jpg)
CVI Perspectives
• Gordon Dutton – Medical
• Lea Hyvärinen – Medical with strong emphasis on optics
• Roman-Lantzy – Educational
![Page 23: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/23.jpg)
Gordon Dutton, MD
• Lower Level CVI– Damage to the visual pathway at the striate cortex – Results in damage to visual acuity, understanding of
what is being seen, and visual fields may be impacted• Higher Level CVI– Damage occurring beyond the striate cortex– Specific functional loss of vision (e.g., movement, shape,
or color)• Both
![Page 24: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/24.jpg)
Visual stimulus is processed in lots of places in the brain
Vision-for-Action
Vision-for-Perception
![Page 25: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/25.jpg)
Dutton Theory ContinuedDorsal Stream
Vision-for-ActionDysfunction in this area:• Difficulty complex visual
scenes• Issues moving through space• Trouble finding an
object/person from within a group
• Inaccurate visual reaching• Decreased lower field• Frustration
Ventral StreamVision-for-Perception
Dysfunction in this area:• Prosopagnosia• Difficulty understanding
facial expressions• Route finding problems• Various visual agnosias
(inability to visually identify objects)
![Page 26: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/26.jpg)
Visual Agnosia
Video: My Strange Brain https://www.youtube.com/watch?
v=kuKqi93FMgQ
![Page 27: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/27.jpg)
Lighten things up Test Your Facial Recognition Skills
1. 2.
3. 4.
![Page 28: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/28.jpg)
Lea Hyvärinen, MDFinnish Pediatric Ophthalmologist
• Dorsal, Ventral, and…. Mirror Neurons–Mirror neurons are activated when
watching others– Important in visual communication– Foundation for imitation of expressions and
thus emotional bonding
![Page 29: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/29.jpg)
Additional Medical Views of CVI: Lea Hyvärinen, MD
• Scotoma: Blind spot in the visual field
• Scotomas and CVI:– Central scotomas “very common in children with
CVI”– If the child is looking away to look at something,
eccentric fixation may be what they’re using
![Page 30: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/30.jpg)
Additional Medical Views of CVI: Lea Hyvärinen, MD
• Saccade: fast movements of the eye that are present in normal visual functioning and important in visual tasks like reading
• Saccade and CVI:– slower than normal– inexact in landing at target–or there may be no fast eye movements at
all
![Page 31: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/31.jpg)
Lea Symbols: Lea Hyvärinen, MD
Optotypes - symbols used to determine visual acuity for prereaders or students with other disabilities
![Page 32: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/32.jpg)
Lea Hyvärinen Cont.
Video: Baby Eyes: A Vision Test for Totshttps://www.youtube.com/watch?
v=3JcAsXuy7ac
![Page 33: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/33.jpg)
Christine Roman-Lantzy, Ph.D
Part 1 APH “CVI Perspectives”
![Page 34: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/34.jpg)
Christine Roman-Lantzy, Ph.D1. Color Preference2. Need for movement3. Visual latency4. Visual Field preferences5. Decreased visual complexity6. Light-gazing & non-purposeful gaze7. Decreased distance vision8. Atypical visual reflexes9. Decreased visual novelty10. Decreased visually guided reach
![Page 35: CVI – Background and Assessment Part 1](https://reader036.vdocuments.site/reader036/viewer/2022070504/568166db550346895ddb0121/html5/thumbnails/35.jpg)
Homework
Identify 3 online or hard copy articles pertaining to CVI.
Write a summary of the findings for one of the articles.