Cortical Visual Impairment

1. Cortical Visual Impairment Children with CVI are those in whom visual dysfunction is caused by lesions in the posterior visual pathways and or occipital lobes and results in temporary or permanent loss of vision.

2. Common Etiologies • Prenatal • Toxemia, intrauterine infection • Perinatal • Asphyxia, meningitis, encephalitis • Acquired • Tumor, trauma, cardiac arrest, seizures, shunt malfunction

3. Diagnostic Criteria • Pupillary reaction is normal • Optic refractive media and fundus appear normal • Blink to threat is absent • Tracking behaviors usually absent

4. Characteristic Behaviors • Eye contact and visual communication skills are poor • Often appear uninterested in surroundings • May turn away from people and events in their environment • Photophobia often coexists with light gazing

5. Visual Functioning • Fluctuations in visual functioning • Familiar objects recognized in one environment and not others • Visual attention is highly variable • Visually locates object then looks away before reaching for object • Distance vision is apparent, but children may bring objects in close to block out visual clutter and chaos • Verbal and tactile cuing is helpful for some children, but may provide too much distraction for others

6. Fluctuations in Visual Functioning • Visual functioning is influenced by: • Tiredness • Unfamiliar environments • Illness • Complex visual information • Poor lighting • Medications • Seizures

7. Visual Perception • Color vision is a strength for children with CVI • Colors are more easily recognizable than shapes • Yellow and red seem to be the preferred colors

8. Visual Perception(con’t) • May only be able to attend to one object at a time • Need sufficient distance between objects to distinguish them • Attend better to objects in motion • Discrimination of foreground from background is difficult

9. Resolution of CVI • 25 to 50 percent of children with CVI recover some useful vision • First three years of life are optimal time for resolution of CVI • First two to three years after accident/trauma to the brain are optimal for recovery of vision However, resolution can occur into the teens and beyond!

10. Assessment and Intervention Strategies • Use vestibular input to alert visual system • Insure proper seating, support and alignment • Avoid overwhelming the visual system with complex visual stimuli • Allow time for observation, assimilation and response

11. Additional Assessment and Intervention Strategies • Illuminated toys • Toys with motion, or those that appear to have motion • Single stimulus • Colored objects and toys • Highlight aspects of toys, objects, shapes, etc. with favorite colors • Wide separation between array of objects • Books with single picture on each page • High contrast between foreground and background • Familiar toys and objects

12. ISAVE CVI Protocol • Complete the Developmental History and Ocular Examination sections of the CVI protocol after interviewing caregivers and reviewing referral information, developmental history, and medical records. • Transfer observations from other ISAVE components to the CVI protocol, especially those from the Ecological Observations component.

13. CVI Protocol: Developmental History • Complete thorough interviews with caregivers and review of medical information • Check all markers on the protocol that are relevant for the child.

14. CVI Protocol: Ocular Examination • Gather information using reports from ophthalmologist or other eye care professional. • Check all markers on the protocol that are relevant for the child.

15. CVI Protocol: Additional Areas • Appearance • Visual Functioning, • Visual Perceptual Characteristics • Sensory Modalities • Posture and • Movement Characteristics

16. CVI Protocol: Impressions and Recommendations Indicate your impressions and recommendations for further services and additional referrals.

17. Summary • Transfer results from the CVI component to the ISAVE Summary Protocol.