als toward evidence-based management of dysarthria
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Amyotrophic lateral sclerosis: Toward evidence-based management of dysarthria
Kathryn M. Yorkston, PhD, BC-NCD
Laura Ball, PhD
David R. Beukelman, PhD
Pamela Mathy, PhD
2
Website
http://www.ticeinfo.com
http://aac.unl.edu
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Amyotrophic Lateral Sclerosis (ALS) Degenerative motor neuron disease Muscle atrophy and spasticity In the limbs and bulbar muscles Dysarthria and dysphagia are common Decisions for SLP re: types & timing of:
– speech intervention– AAC intervention
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Overview
• An introduction to evidence-based decision making• Yorkston - University of Washington
• Question 1: How can early bulbar symptoms be identified?
• Ball - University of Nebraska, Omaha• Question 2: What techniques are appropriate for maintenance of natural speech in progressive dysarthria?
• Beukelman, University of Nebraska, Lincoln• Question 3: Are AAC techniques effective in maintaining communication in ALS?
• Mathy, Arizona State University
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Introduction of Terms
Evidence-based practice
Practice guidelines
Staging of intervention
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Toward Evidence-Based Practice
Medical students do the wrong things in a clinical setting not because of a deficiency in knowledge, but because they don’t make good decisions. They know a lot, but they don’t think systematically.
(Arthur Elstein, Ph.D, University of Illinois, presenting a lecture at University of Washington, April 27, 1999).
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Evidence-Based Practice
. . is a commitment to a constant reexamination of practices through research and outcomes analyses.
- Enhancing our knowledge-base
- Enhancing our decision making
[Sackett et al., (1997)]
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Evidence-Based Practice
. . an approach to decision making in which the clinician uses the best evidence available, in consultation with the patient, to decide upon the option which suits that patient best.”
[Muir Gray, 1997]
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Evidence-based practice is of interest to: Practitioners Policymakers Payers Purchasers Patients Public
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Definition: Practice Guidelines
Clinical practice guidelines are explicit descriptions of how patients should be evaluated and treated. The explicit purpose of guidelines is to improve the quality of care and to assure it by reducing variation in care provided.
- review of evidence- consensus of experts
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Practice GuidelinesExamples from ALS “breaking the news” to patients and
families, nutrition and PEG placements, respiratory insufficiency and mechanical
ventilation, management of emotional lability, and palliative care.
American Academy of NeurologyMiller et al, 1999
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ANCDS - Practice Guidelines
Velopharyngeal Management
Behavioral Tx of Respiration/Phonation
Surgical/Pharm. Tx of Phonation
Speech Supplementation Tx of Speech Rate &
Naturalness
Technical Report due Nov. 2000
Ready for expert review Jan. 2001
Ready for expert review Jan. 2001
Ready for expert review Dec. 2000
To be drafted, 2001
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Definition: Staging
. . . the sequencing of management so that current problems are addressed and future problems anticipated.
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ALS: Stage 1
No Detectable Speech Disorder
. . Diagnosis has been made, but often speakers do not yet exhibit speechsymptoms in those with spinal presentation.
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ALS: Stage 2
Obvious Speech Disorder withIntelligible Speech
. . both the speaker and listener noticechanges in speech - speakers may perceiveextra effort needed for speech.
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ALS: Stage 3
Reduction in Speech Intelligibility
. . . changes in speaking rate, articulation, and resonance are all evident.
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ALS: Stage 4
Natural Speech - Supplemented
. . . natural speech is no longer afunctional means of communication in all situations.
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ALS: Stage 5
No Functional Speech
. . . speakers with advance bulbar ALShave lost functional speech due to profoundweakness.
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Staging
• Question 1: How can early bulbar symptoms be identified?
• Stages 1 and 2 - Early intervention
•Question 2: What techniques are appropriate for maintenance of natural speech in progressive dysarthria?
• Stages 3 and 4 - Moderate to severe dysarthria
•Question 3: Are AAC techniques effective in maintaining communication in ALS?
• Stage 4 and 5: Severe to profound dysarthria
How can early bulbar symptoms be identified?
Laura J. Ball, Ph.D.
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Rationale
With the advent of new drug interventions for ALS, early diagnosis & identification of bulbar symptoms has become critical.
(Quality Standard Subcommittee of the American Academy of
Neurology, 1997)
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Diagnostic techniques that may be implemented to facilitate early identification of bulbar ALS symptoms have become essential for pharmaceutical & communication interventions.
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Review of literature
In the 1990’s, treatments were tested to slow ALS progression. Decision-making regarding these interventions requires – information to place these treatments in the
context of other treatments and – to understand the significance of the efficacy
these treatments may show.
Many drug trials target addressing the earliest possible signs of ALS.
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Bulbar Characteristics
Speech & swallowing symptoms usually parallel -- 71% of 200 consecutive visits(Yorkston, Miller & Strand, 1995)
First symptoms involve:– swallowing difficulties – dysarthric speech– possible nasal resonance changes– laryngeal changes
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Focus on Bulbar Characteristics of Dysarthria
“Neurological or neuromuscular damage causing paralysis, paresis, or incoordination in the bulbar or spinal sensorimotor systems can affect the range, velocity, force, or timing of speech movements as well as the respiratory processes that support speech production.” (Warren, Rochet, Hinton,
1997, p. 81)
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ALS Dysarthria Database
N = 218 visits of persons with ALS documented
Protocol measurement includes numerous factors including intelligibility, speaking rate, aerodynamic measures of oral pressure & nasal air flow, VP descriptor from aerodynamic measures, communication effectiveness ratings (self & listener), & ALS Severity Rating Scale
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ALS Database Questions
Who is going to need AAC? How soon do we know they will need AAC? What will predict loss of intelligible speech
with sufficient time to implement functional interventions?– Assess– Acquire Device– Training
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Question 1
Who is going to need AAC?How do we identify bulbar
characteristics of dysarthria?
How do we assess speech characteristics?
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Speech Assessment Strategies
Intelligibility Speaking Rate Aerodynamic Measurements Pattern of Velopharyngeal Closure ALS Speech Severity Scale Communication Effectiveness
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Intelligibility
Sentence Intelligibility Test (Yorkston, Beukelman & Tice, 1991)
– Measures intelligibility in sentences– Scored by unfamiliar (to speaker &
content) listener– Obtain % intelligibility
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Speaking Rate
Sentence Intelligibility Test Speaking rate in sentences Obtain rate in words per minute
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Rate & Intelligibility
“Changes in speech rate and oral diadokokinetic rates may be precursors of changes in speech intelligibility.”
(Yorkston,Strand, Miller, Hillel & Smith, 1993)
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Rate & Intelligibility
Information obtained from the UNMC database is consistent with previous research, in that when rate decreases to half of normal (or approximately 100 wpm) for an individual with ALS, a precipitous decline in intelligibility may be expected.
R2 = .828, p = .000
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Gary’s Progression
A 40 year old male with bulbar onset of symptoms….
09/1999: 97% intelligible, rate 90wpm
11/1999: 75% intelligible, rate 68wpm
02/2000: 33% intelligible, rate 52wpm
05/2000: 6.8% intelligible, rate 36wpm
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Aerodynamic Measurement Rationale
Accurate description of speech deficits
Develop new treatment approaches Demonstrate quantifiable changes
in physiologic responses(Warren, Rochet, Hinton,
1997)
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Aerodynamic Measurement of Speech Productions
Air Flow Meter – (pneumotachograph with nasal mask)– Normally no flow unless /m, n, /
Air Pressure Transducer – (flexible tube placed laterally on tongue)– Normal between 3-8cm H2O)
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Pattern of VP ClosureObtained from Aeros printouts. 1. VP closure on pressure consonants 2. Initial VP insufficiency, eventually closes 3. VP insufficiency on some consonants,
approximates but never closes 4. Initial VP closure, insufficient by end of
utterance 5. Excessive VP insufficiency on all
pressure consonants
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VP Closure & Intelligibility
Consistent with Intelligibility and Speaking Rate measures, VP closure and Intelligibility measures remain fairly steady until the person with ALS completely and consistently loses velopharyngeal closure.
R2 = -.393, p=.005
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VP Closure & Speaking Rate
Examination of data assessing VP closure and Speaking Rate indicate a pattern similar to that identified with Speaking Rate and Intelligibility.
When Speaking Rate approximates 100wpm, Intelligibility takes a rapid & precipitous decline.
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VP Closure & Rate
Likewise, when Speaking Rate approximates 120wpm, the Pattern of VP closure changes to demonstrate progressively more consistent VP incompetence. Another decline is observed at the 100wpm mark.
These data indicate that VP Closure Pattern/Rate changes precede Intelligibility/ Rate changes in persons with ALS.
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VP Closure & ALS Speech Rating
Pearson Product-Moment Correlation
(R2 = -.417 p = .002) With increase in VP rating,
observe lower ALS Speech Ratings
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Question 2
How soon do we know about the loss of natural speech?
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Communication Effectiveness Modified Index (Lomas, 1989)
Measure societal limitation
perceived when communicating Likert-type scale
– 0 = not at all able– 6 = very effective
10 contextual situations
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I am effective at conversing with:1. familiar persons in a quiet environment.2. strangers in a quiet environment.3. a familiar person over the phone.4. young children.5. a stranger over the phone.6. while traveling in a car.7. someone at a distance.8. someone in a noisy environment.9. before a group.10. someone in a long conversation (>1 hour).
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Intelligibility & Communication Effectiveness
Communication effectiveness scores followed a stair-step decline following a decline in intelligibility.
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Communication effectiveness declines occurred at...
1st at 95% > intelligibility (m = 5.5)!! 2nd at 90-95% intelligibility (m = 4.7) 3rd at 80-90% intelligibility (m = 3.7) 4th at 70-80% intelligibility (m = 2.3) Final at < 70% intelligibility (m = 1.5)
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Intelligibility & Communication Effectiveness
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Intelligibility & Communication Effectiveness
With some slight (nonsignificant) differences, speakers with ALS and their frequent communication partners (spouses, children, caregivers) demonstrate similar descriptions of communication effectiveness.
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Recommendations
It is recommended that evidence-based speech assessment strategies be implemented into a protocol to facilitate early identification of bulbar ALS symptoms.
Early identification may promote earlier diagnosis of ALS & provide a more reasonable timeline to physicians wishing to implement drug trials & patients wishing to take advantage of them.
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Maintaining the Use of Natural Speech (David Beukelman)
Behavioral Interventions
Environmental Interventions
Prosthodontic Interventions
Supplemented Speech Interventions
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Behavioral Interventions Speaking rate modification Speakers usually reduce rate with intervention--
especially with cognitive changes. Maintain coordinated respiratory patterns Coordinated thoracic and abdominal breath
(speech & grammatical structure) Reduce fatigue Conserve energy for communication Eliminate oral or non-speech exercises
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Prosthodontic Interventions
Palatal lift
Palatal augmentation (drop-down)
Voice amplification
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Palatal Lift Evidence
Gonzalez & Aronson (1970). Aten, et al. (1984).
Esposito et al. (2000) retrospective study 21 of 25 speakers with ALS decreased hypernasality 2 of 25 refused to wear the lift 4 of 25 received no benefit Progression of tongue and lip weakness almost always
cause for lack of benefit.
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Palatal Augmentation
Esposito et al (2000).
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Environmental Interventions
Optimize hearing of frequent listeners
Optimize adverse speaking situations– Reduce background noise– Mute TV– Amplify speaker in meetings, groups, & noise– “Private conference room” –
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Supplemented Speech Interventions Alphabet Supplementation
Topic Supplementation
Mixed Topic & Alphabet Supplementation
Gestural Supplementation
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Information from Speech Signal
(Speech Intelligibility)
Information from Non-speech Sources
Understanding
Poor
Poor
Rich
Rich
Mutuality Model (Lindbolm, 1990)
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Intelligibility
Acoustic Signal
Speech Impairment&
Compensatory Strategies
ListenerProcessing
Speech Intelligibility
Language KnowledgeWorld Knowledge
Disability Knowledge
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Speech Signal Information Speech Impairment
& Compensatory Strategies
AcousticSignal
ListenerProcessing
Speech Comprehensibility
Signal-IndependentInformation Semantic Context Syntactic Context Alphabet Gestures
Comprehensibility
Language KnowledgeWorld Knowledge
Disability Knowledge
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Alphabet + Semantic Topic BoardSmall Talk
FamilyFamily
Personal
Transportation
Trips
Weather
Shopping
ChurchFood
Sports
Start over
Health
A B C D E F G
H I J K L M N O
P Q R S T U V
W X Y Z
No
Yes
Please repeat words
Point to first letter
Will spell words
Schedule
Wait
Don’t know
Maybe
Forget it
Please stop
Not finished
Not done
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Alphabet Supplementation
Beukelman & Yorkston (1977)– 42% & 47% improvement in intelligibility (TBI & BS Stroke)
Schumacher & Rosenbek (1986)– 57% improvement in intelligibility (PD)
Hustad (1999) (Pilot for Dissertation)– 42.5% Improvement in Intelligibility (CP)
Crow & Enderby (1989)– 15% Mean improvement in intelligibility (speech signal only) (mixed group of
speakers)
Hustad & Beukelman (Submitted)– 19% Mean improvement in intelligibility (Alphabet information with habitual
speech) (CP)
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Topic Supplementation
(Dongilli, 1994)
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Topic Supplementation (Con’t)
Carter et al. (1996).– 9% Mean improvement in intelligibility
Hustad & Beukelman (1998)– 10% Improvement in intelligibility
Hustad & Beukelman (Submitted)– 10% mean improvement in intelligibility (Topic
information with habitual speech (CP).
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Semantic Supplemented Speech
(Hammen, Yorkston, &
Dowden, 1991)
Speaker Group Sentence Intell(%) Sentence Intell(%)
No Context Semantic Context
Profound 2 20
Severe 27 67
Moderate 64 96
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Mixed (Topic + Alphabet) Supplementation Hunter, Pring, and Martin (1991) 15% relative to topic cues only.
Hustad & Beukelman (Submitted) 34% Mean improvement for mixed
compared to no cues (Mixed cues with habitual speech) (CP)
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Gestural Cues
Garcia & Cannito (1996). – 25% Improvement in low predictive context– 22.5 Improvement in high predictive context
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Techniques for Improving Comprehensibility (Speaker-1) Provide listener with context Don’t shift topics abruptly Use turn-taking signals Get your listener’s attention Use complete sentences Use predictable types of sentences Use predictable wording Rephrase you message
Yorkston, Beukelman, Strand, & Bell, 1999
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Techniques for Improving Comprehensibility (Speaker--2) Accompany speech with simple gestures Take advantage of situational cues Make environment as friendly as possible Avoid communication over long distances Use alphabet board supplementation Have a handy backup system
Yorkston, Beukelman, Strand, & Bell, 1999
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Techniques for Improving Comprehensibility: (Listener-1) Know topic of conversation Watch for turn-taking signals Give your undivided attention Choose time and place to talk Watch the speaker Piecing together the cues Make the environment work for you Avoid communicating over long distances
Yorkston, Beukelman, Strand, & Bell, 1999
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Techniques for Improving Comprehensibility (Listener-2) Make sure your hearing is as good as possible Decide on and incorporate strategies for
resolving communication breakdowns Establish some rules of the game Facilitate communication with others
Yorkston, Beukelman, Strand, & Bell, 1999
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AAC & ALS
Pam Mathy
AAC Methods Used By Individuals Who Have ALS (Pam Mathy)
Unassisted methods--these methods do not involve any form of chart or electronic device
Low tech methods--these methods use some form of chart (e.g., alphabet board) and some means to access it (e.g., finger, light pointer, partner scan). Also included here is handwriting (e.g., paper, pencil, dry-erase boards, magic slate)
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Laser Pointer With Alphabet Board
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Partner Assisted Manual Scan Board
.
I YOU A AND ON GET
TO IT IN DO IF FOR
THE IS OF BUT BE I'M
MY
ME
THIS SO WILL GO NOT OR
THAT CAN WITH WAS HOW
LIKE AREDON'TWHATHAVE
1. E A S T O
2.
3.
4.
5.
N R U I H F J
L Y
C W K M B Q Z
XVPDG
6.
7.
8.
9.
10.
SPACE STARTOVER
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Partner Assisted Manual Scanning
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Handwriting Using “White Board”
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AAC Methods Used By Individuals Who Have ALS
High tech methods--these methods involve use of an electronic device– Uni-Access Devices: Synthesized Speech Devices
Accessed Primarily Using Manual Direct Selection (e.g., LightWriter, Link, IMPACT)
– Multi-Access Devices: Synthesized Speech Devices Designed To Support Multiple Access Methods (e.g., Freedom 2000, DynaVox)
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Uni-Access Devices: LightWriter Series--Zygo
Dual display, direct select & scanning, DECtalk, custom-keyboardarrangement, very portable, letter-coding,phrase storage.
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Uni-Access Devices: Link—Assistive Technology Inc.
Direct-selectionaccess only,Letter-coding,Phrase storage,DECtalk,Standard size keyboard,Relatively low-cost.
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Uni-Access Devices: IMPACT—ENKIDU Research
Handheld Portable IMPACT combines a large keyboard (80% of full size) with a touchscreen to provide additional methods of message production. The expanded touchscreen means that you can have more (or larger) onscreen buttons, allowing for more varied augmentative interfaces. With its nylon carrying case, the Handheld can be used effectively while standing or sitting. Inputs:Touchscreen, keyboard, scanning.
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Multi-Access Devices: E Z Keys for Windows—Words +
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Multi-Access Devices: DynaVox Sunrise Medical
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Switches and Mounts
Slimarmstrong (Ablenet)
Jellybean switch (Ablenet)
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Decision Parameters in AAC Intervention Disease Progression Employment Status Age Motivation to Communicate Support (family, friend, employer)
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Disease Progression
Using ALS severity scale (ALSSS) (Hillel, Miller,
Yorkston, McDonald, Norris & Konikow, 1989 Yorkston, et. al. (1993) followed
101 individuals Fifty eight men Fifty two women
Across 303 clinic visits Six profiles were identified based on Speech,
Upper Extremity and Lower Extremity Functioning
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Functioning Cutoffs on ALSSS Used to Identify Groupings
Adequate speech = 5 or greater (Stages 1 – 3). Poor speech = 4 or less (Stages 4 and 5) Adequate UE = 5 or greater (partial – complete
use of UE) Poor UE = 4 or less (needs assistance in self-
care, can’t use pencil/pen) Adequate LE = 7 or greater (noticeable gait
changes – normal ambulation) Poor LE = 6 or less (impaired mobility--requires
cane, walker, wheelchair)
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Disease Progression Groupings Identified by Yorkston, et. al.
Group 1 (46.5%)--adequate speech, adequate UE Group 2 (20%)--adequate speech, poor UE Group 3 (16%)--poor speech, adequate UE and LE Group 4 (8%)--poor speech, adequate UE, poor LE Group 5 (2.5%)--poor speech, poor UE, adequate
LE Group 6 (7%)--poor speech, UE and LE
89
AAC Interventions Used by Disease
Progression Group Group 1 (46.5%)--adequate speech,
adequate UE– None– Portable amplifiers– Alphabet Supplementation
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AAC Interventions Used by Disease Progression Group
Group 2 (20%)--adequate speech, poor UE – None– Portable amplifiers– Alphabet Supplementation– Assess for writing augmentation (computer
access) if desired--writing now--speech later
91
AAC Interventions Used by Disease Progression Group
Group 3 (16%)--poor speech, adequate UE and LE– Low tech alphabet boards/supplementation– Handwriting
“Magic slate” “White boards”
– High tech devices depending on needs Community, work, car
– Portable, keyboard-based Phone
– Talking word processors, email for home computer– TTD, FAX
92
AAC Methods Used by Patients With Bulbar Presentation (Groups 3 & 4)
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Category of AAC Method(s) Used “Most of the Time” by Communicative Activity
Conversation
Quick Needs
Detailed Needs
Phone
In depth Info.
Written Comm
Stories
0 2 4 6 8 10 12Number of Patients (Total N=12)
No Tech
Handwriting
Other Low Tech
High Tech
Doesn't Participate
Bulbar Presentation Patients
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AAC Interventions Used by Disease Progression Group
Group 4 (8%)--poor speech, adequate UE, poor LE– Most issues similar to group 3
Portable AAC devices can be mounted on wheelchair
– Attention getting devices
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AAC Interventions Used by Disease Progression Group
Group 5 (2.5%)--poor speech, poor UE, adequate LE– No tech partner dependent auditory scanning– Low tech partner dependent visual scanning– Low tech optical pointing– Portability needs – High tech dedicated and/or multipurpose systems
Light weight, portable Adaptations to home computer
– Attention getting devices
96
AAC Interventions Used by Disease Progression Group
Group 6 (7%)--poor speech, UE and LE– No tech partner dependent auditory scanning– Low tech partner dependent visual scanning– Low tech optical pointing– High tech dedicated and/or multipurpose
systems Check needs for portability--wheelchair mounting Adaptations to home computer
– Attention getting devices
97
AAC Methods Used by Patients With Spinal Presentation (Groups 5 and 6)
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
v
x
x
x
x
x
x
S
S
S
S
S
D (optical pointer)
S
S
S
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
J,P
D,D
I,G
C,A
J,M
O,O
P,M
P,W
L,L
L,J-1
L,J-2
E,V
Dep. Aud. Scanning Facial Expr.
Yes/No Questions
Yes/No Hier.Coded Eye-Blink
Alphabet Board (S or D)
Call Buzzer
Multipurpose Device
98
Category of AAC Method(s) Used “Most of the Time” by Communicative Activity
Conversation
Quick Needs
Detailed Needs
Phone
In depth Info.
Written Comm
Stories
0 2 4 6 8 10 12Number of Patients (Total N=12)
No Tech
Low Tech
High Tech
Doesn't Participate
Spinal Presentation Patients
99
Overall AAC Method Use Breakdown by Communicative Activity (N=6)
Co
nve
rsat
ion
Bas
ic N
eed
s
Det
aile
d N
eed
s
Det
aile
d I
nfo
rmat
ion
Sto
ries
0
10
20
30
40
50
60
70
80
90
100
Mea
n P
erc
enta
ge
No Tech
Low Tech
High Tech
100
Use of AAC Methods by Partner Familiarity (N=6)
Co
nve
rsat
ion
Wit
h
Ver
y F
amil
iar
Par
tner
Bas
ic N
eed
s W
ith
V
ery
Fam
ilia
r P
artn
er
Co
nve
rsat
ion
Wit
h S
tran
ger
Bas
ic N
eed
s W
ith
Str
ang
er
0
10
20
30
40
50
60
70
80
90
100
Mea
n P
erc
enta
ge
No Tech
Low Tech
High Tech
101
Satisfaction With AAC Methods by Communicative Activity (N=6)
Co
nve
rsat
ion
Qu
ick
Bas
ic N
eed
s
Det
aile
d N
eed
s
Det
aile
d I
nfo
rmat
ion
Sto
ries
Wri
tten
Co
mm
un
ica
tio
n0
1
2
3
4
5
6
Su
bje
cts
N=
6
7 (Very Satisfied )
6
5
4 (Neutral)
3
2
1 (Very Dissatisfied)
102
Related References
Yorkston, Miller, Strand (1995). Management of speech and swallowing in degenerative diseases. Tuscon, AZ: Communication Skill Builders.
Warren, Rochet, Hinton. (1997). Aerodynamics. In (M. McNeil, Ed.) Clinical management of sensorimotor speech disorders. NY: Thieme.
Lomas, Pickard, Bester, Elbard, Finlayson, & Zoghaib (1989). The communication effectiveness index: Development and psychometric evaluation of a functional communication measure for adult aphasia. JSHD, 54 (1), 113-124.
103
More references
Mathy, P., Yorkston, K. M., & Gutmann, M. (2000). Augmentative communication for individuals with amyotrophic lateral sclerosis. In D. R. Beukelman, K. M. Yorkston, & J. Reichle (Eds.), Augmentative communication in adults . Baltimore, MD: Paul H. Brookes.
Yorkston, K. M., Beukelman, D. R., Strand, E. A., & Bell, K. R. (1999). Management of motor speech disorders in children and adults. Austin, TX: Pro-Ed.
104
More references Miller, R. G., et al. (1999). Practice parameter: The
care of the patient with amyotrophic lateral sclerosis (an evidence-based review): Report of the Quality Standards Subcommittee of the American Academy of Neurology. Neurology, 52, 1311-1323.
Sackett, D. L., Richardson, W. S., Rosenberg, W., & Haynes, R. B. (1997). Evidence-based medicine. New York: Churchill Livingstone.
Yorkston, Beukelman, & Tice. (1991) Sentence Intelligibility Test. Lincoln, NE: Tice Technologies.