How scientifically valid is the study attached? How clinically useful is this study in your opinion
How scientifically valid is the study attached? How clinically useful is this study in your opinion
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this is not a graded or a writing assignment
How scientifically valid is the study attached?
How clinically useful is this study in your opinion?
Transcribed Image Text:study and was classified as Stage I on the Hoehn and Yahr
Scale.¹4 In the previous few years, the participant and his
wife had noted a reduction in his vocal loudness and speech
intelligibility, as well as a breathy speech quality. As a result,
Mr B was finding it more difficult to be understood in group
situations, where there was background noise and
occasionally while speaking by telephone. His speech and
voice difficulties were beginning to affect his duties as a
coordinator of a community group. In daily life, Mr B began
to avoid speaking by telephone and would often spend the
greater part of his day at home, where he did not have to
talk to anyone. Mr B had not previously received any speech
pathology services. There were also no public or private
speech pathology services offering the LSVT in his local
community at the time of the study. The intensive nature
and commitment of the LSVT programme, and participant
fatigue when driving, made it difficult for Mr B to seek
treatment for his speech and voice difficulties outside his
local area.
and
Prior to treatment, the participant's speech was classified
by the principal investigator as demonstrating mild
hypokinetic dysarthria. This classification was based on
Mr B's pre-LSVT assessment results on acoustic measures of
vocal volume for sustained vowel phonation (81.96 dB),
a monologue (68.13 dB), and a perceptual rating of mildly
reduced overall speech intelligibility in conversation (using
a 5-point rating scale). A videolaryngoscopic examination,
conducted by an ear, nose and throat specialist, revealed
some vocal fold bowing, a feature consistent with IPD. Mr B
wore bilateral hearing aids for his mild-moderate bilateral
hearing loss. He remained on a constant drug regime for IPD
throughout the study.
Procedure
The online treatment was delivered by a LSVT-certified
speech language pathologist (SLP). The SLP was located in
Brisbane, and delivered the treatment to the participant's
home via a PC-based telerehabilitation system. One PC was
located at the SLP site, while the other was a laptop
computer located at the participant's home.
The telerehabilitation system was able to: (1) provide
videoconferencing; (2) present reading material for the
participant; (3) manipulate the web cameras at the participant
site via a robot arm to maintain a clear view of the participant
throughout the session; (4) obtain average measures of
sound-pressure level (SPL), duration and peak frequency via
the system's acoustic speech processor; and (5) capture high
quality video (640 x 480 pixel resolution) and audio,
compressed at 384 kbit/s for later examination. The acoustic
speech processor was connected to the laptop computer via a
USB port. A 128 kbit/s Internet connection was established
between the two videoconferencing systems using the public
telecommunications network (ADSL). The connection
enabled videoconferencing at 320 x 240 pixel resolution
between the two systems.
Home-based speech treatment for Parkinson's
disease delivered remotely: a case report
Prior to treatment, the participant's system was set up in a
quiet room of his home by the principal investigator. This
Journal of Telemedicine and Telecare Volume 16 Number 2 2010
Gabriella A Constantinescu*, Deborah G Theodoros*, Trevor G Russell*,
Elizabeth C Ward*, Stephen J Wilson and Richard Wootton
*School of Health and Rehabilitation Sciences, University of Queensland, Brisbane; *School f Information Technology and Electrical
Engineering, University of Queensland, Brisbane; *University of Queensland, Brisbane, Australia; $Scottish Centre for Telehealth,
Aberdeen, UK
Summary
We investigated the validity and feasibility of online delivery of the Lee Silverman Voice Treatment (LSVT) for the treatment
of the speech disorder of a patient with idiopathic Parkinson's disease. The treatment was delivered in 16 sessions to
the participant's home, 90 km from the speech language pathologist. A PC-based videoconferencing system was used,
operating at 128 kbit/s over the public telecommunications network. The patient achieved substantial improvements
in vocal sound pressure levels during sustained vowel phonation (6.13 dB), reading (12.28 dB) and conversational
monologue (11.32 dB). There were improvements in the duration of sustained vowel phonation (4 s). Improvements were
also perceived in the degree of breathiness and roughness in the voice, and in overall speech intelligibility in conversation.
The patient was very satisfied with the audio and video quality of the conferencing, and with the online treatment overall.
He reported a preference for online sessions for the future management of his condition, rather than face-to-face
treatment. Remote LSVT delivery was found to be feasible and effective.
G A Constantinescu et al. Home-based speech treatment for Parkinson's disease
of
took approximately 10 minutes to complete. The
participant was shown how to perform the basic functions
required for treatment, including turning on/off the PC,
activating/closing the application and positioning the
headset microphone. Once the set-up was completed, the
microphone distance was adjusted to 5 cm from the corner
of the participant's mouth. This helped to reduce sound
distortion, maximize visibility of the participant's face,
and allow for accurate recordings of pitch and SPL. To verify
the positioning of the microphone, the SPL (dB-C) data
generated by the system's acoustic speech processor was
then confirmed against a conventional Digital Sound Level
Meter (Model No. 23-553, Radio Shack) during three
sustained phonations of the vowel /a/. The participant was
instructed to avoid adjusting the microphone arm over
the course of treatment and to take care where he placed
the headset microphone when not in use. During the
treatment, the SLP communicated with the participant via a
headset microphone during videoconferencing. The SLP
controlled all displays on the participant's screen, without
the need for the participant to operate the system.
Introduction
Home telecare is increasingly being used to help elderly and
infirm people remain independent within their homes by
improving their access to health care. ¹.2 Home telecare is
ideal for people with Parkinson's disease (PD) as it can
reduce barriers t service access such as the travel difficulties
associated with the large distances to specialised health-care
facilities that are frequently encountered in Australia and in
other countries.³ Idiopathic Parkinson's disease (IPD) is a
chronic degenerative disease. The motor speech disorder
associated with IPD is known as hypokinetic dysarthria and
is characterised by reduced loudness, monotony of pitch
and loudness, inappropriate silences, variable rate and short
rushes of speech, imprecise articulation, and a harsh and
breathy voice.* Hypokinetic dysarthria can affect a high
proportion of people with PD and progresses in severity over
time.6-8 As a result of the reduced speech intelligibility,
people with PD often experience communication
difficulties which may lead to isolation and may reduce
their quality of life,8,9
At present, the most effective, evidence-based treatment
for PD and hypokinetic dysarthria is the Lee Silverman Voice.
Accepted 10 June 2009
Correspondence: Gabriella Constantinescu, Division of Speech Pathology,
University of Queensland, St Lucia 4072, Australia (Fax: +61 7 3870 3998;
Email: gabriella@hearandsaycentre.com.au)
Journal of Telemedicine and Telecare 2010; 16: 100-104
LSVT programme
The LSVT sessions were delivered according to standard
clinical practice, for one hour per day, four days a week,
for four weeks,10,11 The daily sessions included maximum
duration of sustained vowel phonation, fundamental
frequency range, functional speech loudness drills and
hierarchical speech loudness tasks. The tasks were
performed at high intensity and with maximum effort to
promote increased respiratory drive, vocal fold adduction
and carryover of the louder voice into functional
communication. Homework reading materials were emailed
to the participant at the end of each session.
Outcome measures
Pre- and post-LSVT assessments were conducted in the
traditional face-to-face manner in Brisbane by two SLPs who
had not taken part in the treatment. A battery of acoustic
and perceptual measures was used in these assessments.
The acoustic measures were obtained using the LSVT
Evaluation Protocol¹0 and included: (1) average SPLs of the
participant's speech during six phonations of the vowel /a/,
reading of the standard 'grandfather passage', ¹5 and during
a 30 s monologue about a topic of interest; (2) the average
duration of six sustained vowel phonations; and (3) the
pitch range obtained from the average of the highest and
lowest frequencies from a series of six vocal glides, that was
then converted to a maximum range in semitones.¹6
The acoustic measures were obtained using the online
system's acoustic speech processor.
Perceptual measures of voice and speech included ratings
of voice variables (breathiness, roughness, loudness level,
loudness and pitch variability), overall articulatory
precision and overall speech intelligibility in conversation.
The variables of breathiness, roughness and overall
101
Treatment (LSVT). This is a structured programme which is
delivered intensively in 16 treatment sessions and promotes
increased respiratory drive, vocal fold adduction and
increased vocal loudness in everyday communication. 10,11
Improvements following traditional face-to-face delivery of
the LSVT have been reported in vocal loudness, quality and
speech intelligibility, with these positive effects maintained
up to 12¹² and 24 months post-treatment. ¹3
Despite the effectiveness of the LSVT in the management
of dysarthria in PD, patient access to face-to-face speech
pathology services for this treatment remains limited due
to restricted availability of trained clinicians, conflicting
caseload priorities and patient access barriers. The aim of
the present study was to investigate the validity and feasibility
of remote online LSVT delivery for a single case of IPD
using PC-based videoconferencing over the Internet.
Our hypothesis was that LSVT can be effectively delivered
remotely, with treatment outcomes similar to those for
traditional face-to-face LSVT.
Methods
Mr B, a 65-year-old retired man living in a regional city,
90 km north of Brisbane, was recruited to the study. Ethics
approval was obtained from the appropriate committee.
Mr B had been diagnosed with IPD six years prior to the
DOI: 10.1258/jtt.2009.090306
G A Constantinescu et al. Home-based speech treatment for Parkinson's disease
articulatory precision were determined from pre- and
post-LSVT readings of the standard 'rainbow passage'. ¹7
A 30 s monologue was used to determine the loudness level,
pitch, loudness variability and overall intelligibility in
conversation.
The ratings on all of the perceptual variables were made
using Direct Magnitude Estimation (DME), a scaling
method that allows the rater to assign any numerical value
to the variable and rate the sample against a 'standard' or a
representation of a midrange impairment of that variable
for improved reliability, 18-20 A set value of 100 was used to
represent the standard, 18,21 For the variables of loudness
I and variability, pitch variability, overall speech
intelligibility in conversation and overall articulatory
precision, a rating of 50 suggested that the sample was only
half as clear as the standard, while a rating of 200 indicated
that the sample was twice as clear as the standard.20 For the
variables of roughness and breathiness, however, a sample
that was rated lower than 100 represented an improvement
in quality. DME ratings were made by two experienced SLPS
who were blinded to the study intent. For each variable, the
raters listened to the standard followed by the pre- and
post-treatment speech samples in random order.²1 A
different standard was used for each variable. 20 An average
pre- and post-treatment value was calculated for each
variable, which was then converted to a logarithmic value
19,22
and represented as a geometric mean.
The participant also completed a satisfaction
questionnaire (5-point scale) relating to the online
treatment modality. The questionnaire determined his
satisfaction with: (1) the online treatment sessions
(responses ranging from would not participate again to
would prefer these types of sessions to face-to-face sessions
for future management of PD); (2) the audio and video
quality during the sessions (poor to excellent); and (3)
overall satisfaction with online treatment (not at all satisfied
to very satisfied).
Results
Descriptive comparisons and degree of change were
determined between the pre- and post-LSVT acoustic and
perceptual measures. For the acoustic variables, substantial
treatment gains were made on all SPL tasks (6.13 dB.
improvement on sustained vowel phonation; 12.28 dB on
reading and 11.32 dB on monologue loudness), and on the
duration of sustained vowel phonation variable (4 s
improvement). Pitch range failed to show an improvement
with treatment. The results are summarised in Table 1.
For the perceptual variables, treatment gains were
observed for measures of breathiness (a 30.33 DME value
reduction), roughness (14.86 DME reduction) and overall
speech intelligibility in conversation (12.43 DME
improvement). No treatment changes were evident for
overall articulatory precision, with this variable remaining
at the high pre-treatment DME value of 162.18. Lower
102
Table 1 Pre- and post-LSVT values and treatment changes
Task
Pre-LSVT Post-LSVT
Sustained vowel phonation (dB)
Reading (dB)
Monologue (dB)
Duration of phonation (s)
Pitch range (semitones)
"Improvement
81.96
71.42
68.13
9.67
12.87
88.09
83.70
79.45
13.67
9.01
Change
Discussion
6.13*
12.28'
11.32
4.00
-3.86
Table 2 Pre- and post-values and treatment changes (values shown are
DME ratings)
Task
Pre-LSVT Post-LSVT Change
75.00 44.67
-30.33
-14.86-
Breathiness
Roughness
79.43
Loudness level
186.21
120.23
Loudness variability
Pitch variability
104.71
Articulatory precision
162.18 162.18
Overall speech intelligibility in conversation 128.82 141.25
*Improvement
64.57
151.36
114.82
95.50
- 34.85
-5,41
-9.21
0
12.43
performance with treatment was evident on the remaining
variables of loudness level (a 34.85 DME reduction),
loudness variability (5.41 DME reduction) and pitch
variability (9.21 DME reduction). The pre- and post-LSVT
values and treatment changes are summarised in Table 2.
On the participant satisfaction questionnaire, Mr B rated
the audio and video quality as excellent. He was very
satisfied with the online treatment overall and indicated
that he would prefer online sessions to face-to-face for
future management of his condition. Overall, there were no
failed treatment sessions and the majority (n = 13) of the
sessions ran very smoothly, without technical difficulties
and with adequate audio and video quality for treatment
delivery. During the remaining three sessions, some
C
networking difficulties considerably reduced the audio and
video quality. These problems were solved by disconnecting
and re-establishing the videoconferencing connection
between the two telerehabilitation systems.
The present case report demonstrates the feasibility of
remote online delivery of the LSVT via a PC-based
videoconferencing system operating on a 128 kbit/s
Internet connection and supports the study hypothesis.
On the whole, Mr B showed substantial improvements with
remote LSVT for most of the acoustic and perceptual
variables, and these were similar to the treatment outcomes
reported in the literature for IPD participants with mild to
moderate hypokinetic dysarthria following face-to-face
LSVT,11,12,23-26 The post-treatment values for the SPL
variables were also consistent with the average values
reported for two groups of healthy older adults speaking at a
comfortable loudness level, in studies with similar
Journal of Telemedicine and Telecare Volume 16 Number 2 2010
Transcribed Image Text:G A Constantinescu et al. Home-based speech treatment for Parkinson's disease
assessment procedures.27.28 It is possible that the lack of
perceived improvement in some speech and voice variables
(pitch range, loudness level and variability, and overall
articulatory precision), was related to the participant's mild
degree of hypokinetic dysarthria which made it difficult for
the raters to perceive changes in these variables following
treatment. It is recognised that the perception of speech and
vocal changes is more difficult in milder degrees of speech
impairment and may not be as accurate as objective
measurement. Despite the lack of substantial improvements
in some specific speech and voice variables, the participant
demonstrated improved speech intelligibility in
conversation and reported improved performance in
everyday speech activities following treatment.
Participant's perspectives
Overall, Mr benefited from remote LSVT and found the
treatment useful for increasing his loudness to pre-morbid
levels, and for integrating and maintaining the treatment
gains of improved loudness level, vocal quality and speech
intelligibility in daily life. As a result of these positive
treatment changes, Mr B felt that his speech sounded
natural and close to how he remembered it prior to PD.
He regained his confidence in talking to his family and
friends, gave a speech at his daughter's wedding, and began
speaking again by telephone and in group meetings.
Overall, Mr B was very satisfied with the online treatment
and rated the video and audio quality 7 of the online
application as excellent. His level of hearing loss, which was
corrected by hearing aids, did not interfere with his ability
to hear instructions over the videoconferencing link.
Interestingly, on the satisfaction survey, Mr B reported that
he would prefer online sessions to face-to-face for the future
management of his condition. He felt that the online
method provided: ease of access to treatment without the
nuisance of travelling and the need to leave his own home;
time-savings from not having to travel; and a friendly
technical interface for treatment using reliable technology.
The convenience of remote online LSVT proved to be a
highly motivating factor for Mr B. Similar findings have also
been reported in other telehealth studies where patients
were motivated and accepting of the technology used when
they could be treated in their natural or least restrictive
environment. 30,31
Clinician's perspectives
The real-time videoconferencing feature of the application
and the ability to capture and display SPL and frequency
data and display therapy materials online were important to
the successful delivery of the treatment, allowing the
clinician to: provide timely instructions to the participant
and assist with shaping correct voice productions and
overall calibration; monitor the loudness level, pitch level
and vocal quality; and maintain good rapport with the
participant. From the clinician's perspective, the online
application was user-friendly and allowed effective delivery
Journal of Telemedicine and Telecare Volume 16 Number 2 2010
of remote home-based LSVT via the public network.
There were no failed treatment sessions and the majority
of sessions ran very smoothly, with adequate audio and
video quality for treatment delivery. On only three
occasions was the SLP required to disconnect and
re-establish the videoconference connection due to
networking difficulties.
Although occasional audio delays were also encountered
during treatment, they were effectively managed by the
participant and clinician who waited until the other had
clearly finished speaking before replying, and by the
clinician using shorter and more precise instructions.
Strategies, however, were needed to maximise the video.
Stratez
quality, as the frame rate and pixelated video image
especially during movement made it more difficult for the
clinician and participant to clearly view each other during
the session. Useful techniques to improve the video quality
included: sitting relatively still in front of the PC during the
sessions; the SLP using easy to detect hand-cues for quick
input; relying more heavily on specific verbal directions and
participant feedback rather than on visual information; and
using the store-and-forward modality to record the desired
task when necessary. These strategies were easily adopted in
the sessions and aided the smooth delivery of treatment.
The use of higher Internet bandwidth would improve the
interface and thus more closely resemble the face-to-face
modality, reduce the audio and video difficulties and lessen
the need for compensatory strategies.
framment
Other procedures necessary to ensure the smooth delivery
of treatment in the home environment were identified
during the study. The sessions were conducted in a quiet
room of the participant's home, which reduced any
household distractions and noise, and telephone calls
were not taken during the sessions. Furthermore, the
microphone distance from the participant's mouth was kept
constant, to ensure that the acoustic levels were constant
between sessions. The participant also took great care to
ensure that this distance was maintained. It would be useful
in future for the SLP to be able to provide audio-recordings
of the participant's performance as a form of feedback for
them. This additional capability would make online LSVT
even more similar to face-to-face treatment.
In conclusion, the treatment gains, the high participant
satisfaction and motivation with remote LSVT illustrate the
potential of this type of service delivery for people with PD.
Remote treatment may assist in reducing the effects of
physical disability, transport and travel difficulties, and
distance for those with PD, which at present represent
substantial barriers to service access. Remote treatment may
also facilitate earlier access to intervention, thus allowing
individuals to remain independent and active within their
www
own homes and communities. Because the present report
concerns a single case, the findings cannot be generalised to
the wider PD population. Future large-scale studies are
needed to investigate the effectiveness of remote online
LSVT with a larger number of participants with PD and
dysarthria severity levels and greater numbers of treating
clinicians.
103
G A Constantinescu et al. Home-based speech treatment for Parkinson's disease
Acknowledgements: This research was funded by a National
Health and Medical Research Council Project Grant 301029.
The work forms part of the doctoral thesis of Gabriella
Constantinescu at the University of Queensland. We thank
Parkinson's Queensland Incorporated, the participant,
Roy Anderson, Anne Hill, Monique Waite, Jasmin Cowles
and Christina Iezzi for their contribution to the research.
LSVT is a registered trademark.
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