OCTH 266: The Occupational Therapy Low Vision Evaluation for Clients With Age Related Eye Disease

Typical Aging and Vision

Decreased visual acuity

Decreased visual accommodation

Floaters

Dry eye

Need more light

Glare sensitivity

Reduced light/dark adaptation

Reduced contrast sensitivity

Reduced color perception

Reduced visual attention

Functional vision

How the person functions

Visual function

How the eye functions

Legally blind

Describes a person who has severely impaired vision; visual acuity of 20/200 that cannot be improved with corrective lenses or having a visual field of less than 20 degrees.

-not a clinical term

Low vision

a vision problem that makes it hard to do everyday activities.

It can't be fixed with glasses, contact lenses, or other standard treatments like medicine or surgery

-use of remaining vision

Cones of the eye

Detect color

-lower sensitivity to light

-day vision

-Most sensitive to direct axial rays

-in fovea

-chromatic: 3 types

Rods of the eye

-high sensitive to light; night vision

-low acuity

-not in central fovea

-achromatic: one type

For adults with low vision addressing reading performance should

routinely use the following interventions:

Comprehensive low vision rehab

Eccentric viewing training

Practitioners should use the following interventions on a case-by-

case basis:

Vision specific AT

Mainstream technology to improve reading

Visual search training for hemianopsia

Implications for practice

Multicomponent low vison rehabilitation to facilitate ADL/IADL

performance, reading for occupational performance, and leisure/social participation

Eccentric viewing for central VFD

Multimorbidity

presence of two or more chronic conditions at the same time in one individual; high prevalence has several negative consequences:

-high mortality rate

-increased healthcare utilization

-increased healthcare expenses

-influencing overall functioning and quality of life

Clinical low vision evaluation

History: Medical dx & history, visual dx & history, eye dominance

Visual Acuity: Distance acuity, near and reading acuity

Lighting and Contrast: Contrast sensitivity, contrast enhancement,

glare/sensitivity, light/dark adaptation

Visual fields: Peripheral, central, scotoma, preferred retinal locus

Neurological exam: Extraocular, binocular, pupils, color, eye health, refraction, visual hallucinations

Low vision eval: history

Medical dx & history, visual dx & history, eye dominance

Low vision eval: visual acuity

Distance acuity, near and reading acuity

Low vision eval: lighting and contrast

Contrast sensitivity, contrast enhancement, glare/sensitivity, light/dark adaptation

Low vision eval: visual fields

Peripheral, central, scotoma, preferred retinal locus

Low vision eval: neurological exam

Extraocular, binocular, pupils, color, eye health, refraction, visual hallucinations

Common visual issues

Decreased visual acuity

Decreased contrast sensitivity

Decreased color discrimination

Sensitivity to light/glare

Reduced dark/light adaptation

Clinical observations: visual acuity

Difficulty recognizing faces

Easier to see out of the corner of their eyes (peripheral vision)

Vision fluctuates throughout the day

Colors are difficult to distinguish (especially dark colors)

Uses a flashlight or additional light to view objects

Quick screen(reading card in standard print)

Clinical observations: contrast sensitivity

-Inability to recognize faces

-Difficulty performing tasks or functional mobility in low lighting conditions

-Difficulty distinguishing colors

-Requests additional lighting when completing tasks

-Quick screen (ask client to fill a clear glass with water to within ½" of the top)

Near normal to moderate vision loss

Difficulties with clothing selection

Difficulties with grooming

Difficulties with functional mobility

Performance barriers:

• Decreased contrast

• Decreased illumination

• Organization

Serve and profound vision loss

Difficulties with self-feeding

Difficulties with dressing

Difficulties with grooming

Difficulties with functional mobility

Additional barrier of glare

Increased reports of simplification strategies

Increased reliance on others for performance

Performance barriers:

• decreased contrast

• Illumination

• organization

IADL profound vision loss

Additional barrier of too much lighting and glare

Frequent use of AE (magnifiers and pillboxes) and AT (CCTV)

Increased reliance on others for performance

Difficulties with novel environments

Implications for OT practice

• Provide at least some intervention in the clients' home environment

• Screen clients for depression and address psychosocial adjustment to vision loss

• Collaborate with and refer clients to other rehabilitation providers,

particularly mental health professionals

• Solicit and enhance caregiver involvement

Promoting participation

Screen for visual deficits with occupational performance

Collaborate with other professionals

Assessing person-environment fit

Improve visibility of task

Improve visibility within the environment

Address adjustment issues

Provide resources

Collaborate on goals- need to know issues and what to ask

-Some areas may require additional training- optical devices- some may not e.g., cell phones

Home lighting

-Less light reaches the retina for older adults as a result of normal aging processes

-Consider task lighting and environmental lighting

-Low Vision Home Assessment (LVHA)

-Home Environment Lighting Assessment (HELA)

Home safety issues for low vision

Lighting (Task/Environmental)

Contrast

Visual Distractions (Pattern/ Clutter)

Glare

Compensation Strategies

Compensation strategies

Involve the use of other sensory systems, devices, or methods to simplify or eliminate tasks or steps in activities that typically require vision

Principles in home interventions

• Lighting

• Color and contrast

• Organizations

• Texture and touch

• Sound

• Labels, Lettering, and Marking

• Safety

Types of magnification

Relative size magnification (increase size of object)

Relative distance magnification (decrease distance to object)