FOTAFlorida Occupational Therapy

Association

FOTA Annual ConferenceNovember 8-9, 2013Daytona Beach, FL

Attended by: Laura Moritz & Elke Lacayo

Identifying Risk for Falls in the Adult Client with Visual

Impairment: Strategies for Prevention

Speakers: • Sarah LaRosa, MOT, OTR/L, CLVT• Bonnie Smith, OTR/L, CLVT

Condensed & modified presentation

by Laura M. & Elke L.

Did you know?

• Visual impairment is one of the primary contributions to falls among elderly persons

CDC report

• Older adults with vision loss are more likely to experience comorbid conditions than people without vision loss

• Implication: Serious consequences for overall health, ability to perform tasks, and to participate in social roles

• Of people 65 years & greater in age vision loss is expected to be 5.7 million

What is low vision?• Impaired vision with a significant reduction in visual

function which is not correctable with conventional glasses, contact lenses, surgery or other medical treatment

• Encompasses individuals with less severe vision loss as well as those who are legally blind

• Legal blindness is defined as: 20/200 or worse in better eye or <20 degrees of visual field (or use Snellen Chart)

Scope of Practice: OT Services for the Client with Low Vision

• From AOTA’s resource manual: “Practice Guidelines for Adults with Low Vision”

-Summary: “Expanding the role of Occupational Therapy in low vision by helping older adults use their remaining vision to participate in desired occupations, supports their need for health & productive lives. Similarly, modifying the home environment to facilitate individual’s safe participation in daily activities contributes to overall health & wellness.

Scope of Practice: Role of OT

• Perform vision screening, lighting assessments, glare assessment, balance screening, home safety assessment:– Modify home environment via lighting change, use

of contrast, obstacle removal, glare management– Training in the use of:• Preferred Retinal Locus (PRL)• Eccentric viewing• Visual scanning, tracking, tracing

Scope of Practice: OT Services for the Client with Low Vision

• Coverage by Medicare for OT in low vision since 1990

• Vision impairment was recognized as a physical disability

• Must be provided under direction of Physician or Optometrist (preferably a low vision specialist)

• Services must be “medically necessary and reasonable”– address lack of independence or safety due to impairment

Key Concepts

• The brain sees, NOT the eyes! The eyes merely take a photograph for the brain to process.

• Ocular visual impairment is the direct result of any lesion in the anterior visual system.

• Cortical visual impairment is the direct result of any lesion in the posterior visual system.

• The function of all eye movements is to keep images focused on the fovea!

• It is the sum total of all lobes working together that allows a person to visually process information and adapt to the world around them.

Anatomy of the Eye

Anterior or Posterior?

• Where is the dysfunction?– Is it the camera (the eye; anterior visual system)– Or the computer/processor (the brain; posterior

visual system)– Or both??

Functional Impact of Central Vision Loss (i.e. ARMD, retinal tears)

• ADL problems most apparent– Unable to recognize therapist’s face (mistaken for memory deficit)– Unable to read (exercise programs, bathroom door signs, exit signs)– Cannot identify colors (clothing)– Difficulty with depth perception (stairs, curbs, uneven surfaces)– Unable to see non contrasting objects (get up & go test with dark chair

against dark floor, pills on a counter top, sock on floor)– Lighting may create glare causing increased difficulty with all visual tasks

(i.e., white table top, white linoleum floor)– Difficulty at meal times (spilling, dropping items, inability to identify food

on plate, difficulty cutting bite size pieces)– Slowed accommodation to changes in lighting (especially outside to inside)– Apparent memory deficits—related to inability to use visual memory– Poor rehab motivation due to depression

Macular Degeneration (central vision loss)

Diabetic Retinopathy Functional Deficits

• Reading syringe, reading sliding scale, reading glucometer

• Inspecting skin• Working around the stove or oven (burns)• Photophobia: indoors & outdoors• Reduced activity & mobility levels• Fluctuating acuities

Diabetic Retinopathy (mixed vision loss)

Functional Impact of Mixed Vision Loss

• (i.e. Diabetic Retinopathy: Advanced Glaucoma)• -fluctuating levels of vision (good general & task lighting, use contrast, manage

blood sugars, control intraocular pressure)• -glare sensitivity (glare filters, sunglasses indoor & outdoor, curtain & blind use,

visors)• -inability to perform skin inspection (good task lights & magnifying mirror)• -difficulty reading insulin syringes (syringe magnifier, contrast, lighting,

magnification, prefilled syringes• -reading & ADL problems as with central loss• -mobility problems as with peripheral loss

Glaucoma

• “silent disease”, consider testing if family history• increase intra-ocular pressure leading to optic

nerve damage• “tunnel vision”• Extreme contrast sensitivity loss (i.e. night

driving)• Extreme photophobia• Night blindness

Glaucoma (peripheral vision loss)

Functional Implications of Peripheral Vision Loss

• (i.e. Glaucoma, Retinitis Pigmentosa, CVA)-mobility problems most apparent

*walks into door frames or open doors (use protective techniques, use cane, use scanning)

*does not see furniture or items on floor (improve lighting, tracing techniques, scanning)

*does not see curb or stairs (use contrast, cane, scanning)*walks into open cabinet doors and overhangs (protective

techniques, lighting, scanning, contrast)*unaware of approaching people, cars, bikes (orientation & mobility training, use

of auditory cues, white cane/walker as symbol of vision deficits)*difficulty locating doors, cars, bathrooms, objects (tracing, contrast use,

lighting)*does not scan full sentence when reading/difficulty locating margins/reduced comprehension (marginal cues, typoscopes, scanning techniques, CCTV)*may be glare sensitive (glare filters, sunglasses)*may have difficulties in low light (task lighting, increased general lighting, cane use, night lights)

Retinitis Pigmentosa

Visual Field Loss

Functional Implications

• Problems as seen with field loss from disease• Cognitive/perceptual component of

inattention, neglect• May also have sensory or motor loss• Balance & fall risk increased with multisensory

impairment

TBI

• Wide range of visual deficits including:– Partial to total field losses– Changes in acuity– Perceptual changes– Depth perception losses– Diplopia

-Acquired strabismus -Nystagmus

*Central Sign*Multi-directional

-Photophobia

Common Optic Conditions

• Myopia- if the image falls in front of the retina, it is referred to as nearsighted (+ power)

-corrected with concave/minus lens • Hyperopia- if the image falls behind the retina it is referred

to as farsighted (- power)-corrected with convex/plus lens

• Astigmatism- unequal curvatures occur along the refractive surface such that the rays of light are not focused on a single point on the retina

-creates a blur-corrected using a cylindrical (toric lens)

Aging Eye

• Two types of prescription lens:– Single vision: distance, near, intermediate (ex.

computer, piano, painting)– Multifocal: bifocals, trifocals, progressive lens• Bifocal & trifocal-see line• Progressive- don’t see a line

Why does this matter?• Wearing multifocal lens

– Eye has to focus through the correct lens for the correct distance or there is blur• Ex. Going down steps or curbs, chin tuck to see through top portion of

bifocals or trifocals• Cognitive deficits may reduce correct use• Visual deficits may already induce blur or scotoma• Progressive lenses have zones of no correction in periphery of lenses-

smaller areas of correction than lined bifocals or trifocals

Research to Consider

• “Multifocal glasses impair edge-contrast sensitivity & depth perception & increase the risk of falls in older people”– Lord, S., et al. (2002). Multifocal glasses impair edge

contrast sensitivity & depth perception & increase risk for falls in older people. Journal of American Geriatric Society, 50(11), 1760-6.

– Results of study: more than twice as likely to fall in follow up period

– More likely to fall due to trip, when outside home or walking up or down stairs

More Research

• Loss of edge-contrast sensitivity (steps, curbs, cracks) may more accurately reflect capacity to detect obstacles than acuity

• With recurrent falls, may consult with OD or MD– Re: change to single vision lens– Must have cognitive ability to remember to wear NVO

to read & DVO for mobility

*TIP for OT: find low vision Ophthalmologist or Optometrist in your area to consult with and refer to

Cataract (foggy vision)

Slideshow: What Eye Problems Look Like

• http://www.webmd.com/a-to-z-guides/ss/slideshow-eye-conditions-overview

Importance of Vision Screening

• “one-third of community dwelling people over the age of 65 years fall at least once a year”– 3 categories of falls:

• Falls that result from interference with base of support: trips, slips• Falls that result from externally applied push or self induced

displacement: bending, reaching, turning, or transfer• Falls from physiological event disrupting posture control

mechanism

• (Salonen, 2012)

Impact of Vision Impairment for OT

• 21% of people over 65, by self report, have vision impairment that impacts their ADLs

• If your patient has vision impairment as a secondary problem, ignoring it will impede your progress with their chief complaint

• Falls are a leading cause of hospitalization and mortality in older adults

• Vision is a key component of balance– Vestibular system– Somatosensory system

Vision Screening: Methods & Tools

• Areas to assess include:– Visual fields: central & peripheral– Central distortions (metamorphopsia) or scotomas– Loss of depth perception– Loss of contrast sensitivity & color vision– Response to glare & lighting needs– Perceptual deficits– Occular-motor control– Acuity– Appropriateness of AD such as magnifiers & telescopes

• Obtain History• Observation• Assessments:

– Corneal & pupillary reflex– Tracking/motor control– Pursuits & saccade– Ocular & vestibulo-ocular reflex– Convergence– Strabismus– Eye dominance– Visual fields– Central or peripheral fields– Facial fields– Contrast sensitivity– Color testing– Depth perception– Glare assessment– Acuity screening– “M” or Meter Measurement with Acuity– Reading tests– Multiple Testing tools

Screening to identify risk for falls in the older adult with vision impairment

• Timed up and Go (TUG)• Berg Balance Scale (BBS)• Functional Reach Test• Tinetti Falls Efficacy Scale (FES)• UAB Center for Low Vision Rehabilitation:

Falls Efficacy Scale

Intervention Strategies• After assessing visual function & assessing risk for falls, here are some

simple interventions to increase safety with mobility for the person with visual impairment:

• Eccentric Viewing Training

• Visual Scanning Training

• Smooth Pursuit Training

Eccentric Viewing Training

• macular scotoma – blind, blurred or distorted spot in central field d/t damage in the cone receptor cells responsible for detecting detail & color

• Fovea no longer serves as the point of fixation or retinal locus• Must use a “pseudo fovea” or preferred retinal locus (PRL) for off center viewing to

identify objects• AKA PRL training

– have client perform eye movements drifting in/out of scotoma at varied distances up to 5-8 ft (off center focus & shifting back/forth, i.e. when cooking)

– Use a variety of functional objects (clock, face, building structure, street signs, etc.)– Train in different environments (carry over of technique needs to be everywhere)

• Static• Dynamic• Home• Community

Visual Scanning/Search

*Deficits:– Visual field deficit (VFD)– Visual Scanning: Hemi-inattention and/or Visual Spatial Neglect

*Strategies: -Visual Scanning Training (VST)

-dynavision-laser pointers-scan course-extrapersonal scan boards-post-it notes on a wall-lighthouse strategy-video feedback

Dynavision

Smooth Pursuit Eye Movement Training

• 2013 study published in Neurorehabilitation and Neural Repair

• Randomized Prospective Trial• Subjects; n=45– Right CVA with left VSN & auditory neglect

• Effectiveness of VST vs SPT• Pre-training, post-training, 2 week follow-up• SPT group showed significant improvement at post

training & at 2 week follow-up vs VST group which showed no significant improvement

AOTA tips: Living with Low Vision

• http://www.aota.org/~/media/Corporate/Files/AboutOT/consumers/Adults/LowVision/Low%20Vision%20Tip%20Sheet.ashx

• Patterson Medical Low Vision AE:• http://

www.pattersonmedical.com/app.aspx?cmd=searchResults&sk=low+vision

Depth Perception: must teach monocular cues (cues that can be processed by just one eye)

• Linear Perspective – Parallel lines (i.e. outer edges of road appear to meet)

• Texture– Grassy field appears less textured the farther away it gets

• Gradient– i.e. sidewalk marked for textural changes, slope

• Apparent size of familiar objects– Size of familiar objects– When you see things far away they appear smaller, & when you are

closer they appear larger

Environmental Modifications

• Organize Environment– Structure– Simplify– Reduce background pattern

• Enhance Contrast• Ensure proper illumination• Modify tasks

Referral Services• Check to make sure the client is being followed by an MD to have the

health of the eye routinely examined; Ophthalmologist• Orientation & Mobility Specialists• PT• Low Vision Optometrist• Low Vision OT

• http://www.brookshealth.org/outpatient/locations/center-for-low-vision/

-Sarah LaRosa email: sarah.larosa@brooksrehab.org

• http://www.lowvisionofcentralflorida.com/-Bonnie Smith email: lowvisionrehabilitation@gmail.com

Low Vision Rehabilitation of Central Florida (speaker’s handouts)

• Tips for working with visually impaired

• Sighted Guide Techniques

• Protective Techniques

FSCJ – ILAB

• http://www.fscj.edu/community-engagement/independent-living-for-adult-blind

• Vision Rehabilitation Services

THANK YOU