Visual Impaired Notes
Goals and Objectives
Evaluate children with visual impairments.
Develop interventions for children with visual impairments.
Introduction
Vision aids in:
Identifying attributes like colors and shapes.
Acquiring spatial concepts.
Integrating elements into a coherent whole.
Key variables of visual impairment: type, severity, etiology, age of onset.
Congenital causes account for over 50% of visual impairments.
Incidence in school-aged children estimated at 0.50%.
IDEA 2004 mandates Braille instruction unless inappropriate.
Signs of Visual Difficulties
Signs observable in infants and older children.
Structure of the Eye
Key parts: Cornea, Sclera, Aqueous humor, Iris, Pupil, Lens, Retina, Optic nerve.
Disorders Affecting Vision
Types include:
Refractive errors.
Field defects (central, peripheral, and whole).
Clarity of Vision
Defined by visual acuity levels:
Normal: 20/20.
Mild low vision: 20/30 to 20/60.
Moderate low vision: 20/70 to 20/160.
Severe low vision: 20/200 to 20/400.
Profound low vision: 20/500 to 20/1000.
Total blindness: no light perception.
Legal blindness defined as acuity < 20/200 or field < 20°.
Developmental Considerations
Greater challenges if blindness occurs before age 5.
Difficulties include:
Learning about the world.
Routine tasks and word association.
Concepts of space and social functioning.
Assessment Considerations
Psychological assessment battery required.
Standardized tests may need modification due to lack of norms.
Use background information and functional vision assessment.
Interventions
Focus on helping children achieve competence in:
Academic and social skills.
Orientation and mobility.
Use of assistive devices.
Daily living and recreation skills.
General Teaching Considerations
Conduct thorough case studies.
Educate parents to assist with environment awareness.
Assistive Technologies
Strategies include:
Adapted writing tools and paper.
Magnifiers and Braille devices.
Electronic text strategies (e.g., word processing with speech).
Auditory access devices like talking GPS.
Emphasize equipment and evaluation principles for effective usage.