3. Differential Diagnosis MTD vs SD

8/13/2019 3. Differential Diagnosis MTD vs SD

http://slidepdf.com/reader/full/3-differential-diagnosis-mtd-vs-sd 1/61

Muscle Tension Dysphonia vs. Spasmodic Dysphonia:

An Evidence-Based Approach

Nelson Roy Ph.D.,CCC-SLP, F-ASHA

Department of Communication Sciences DisordersDivision of Otolaryngology-Head Neck Surgery



Spasmodic Dysphonia (SD)

and Muscle Tension Dysphonia (MTD)

– Two enigmatic voice disorders that produce disordered

laryngeal movements and often incapacitating dysphonias

– Presumed to have very different origins and treatments

– Accurate differential diagnosis is essential for timely and

optimal management



The Spasmodic Dysphonias (SDs)

• Neurogenic—adult onset, action-induced, “task-specific ortask-dependent”, focal dystonia

– Adductor SD (ADSD)- voice breaks in vowels (strained-strangledvoice quality)

–

Abductor SD (ABSD)- prolonged voiceless consonants (breathyvoice quality)

– Mixed (ADSD/ABSD)

– +/- Tremor



Muscle Tension Dysphonia?

• A functional voice disorder that can mimic the perceptualfeatures of the SDs

• Recurrent feature in all descriptions is laryngeal andextralaryngeal hyperfunction

• Multiple sources of dysregulated muscle activity – Psychological and/or personality factors that tend to induce tension

– Technical misuses of the vocal mechanism

– Learned adaptations following URI

– Compensation for minor underlying vocal fold pathology

– Increased laryngeal tone secondary to LPR



SD vs. MTD:A Source of Confusion

• Differential diagnosis of SD continues to be based primarilyupon auditory-perceptual assessment

• MTD can mimic the perceptual attributes of the SDs

• Potential for misdiagnosis & inappropriate (needless,wasteful) behavioral, medical, or surgical interventions

• Video examples: SD vs. MTD?



Toward Improved Differential Diagnosis

• An improved understanding of the differences between the SDs and MTD is

necessary to reduce diagnostic confusion and improve management outcomes.

• U of Utah Program of Research (ADSD vs. MTD).

• Many assertions exist regarding features considered characteristic or definitive

of ADSD (e.g. task-specific/dependent, phonatory breaks, falsetto, singing).

• Most of these assertions have not been tested, nor has it been determined

whether MTD behaves in a similar manner (or shares the same features as

ADSD).

• Assertion-based vs. Evidence-based practice in differential diagnosis.



Assertion # 1:

Task “Specificity”/ “Dependency” in ADSD?

• ADSD has been described as “Task specific” or “Task Dependent”

• Task Dependency in ADSD…The severity of symptoms (i.e., degree of dysphonia, number of voice

breaks, degree of strain) will vary according to the demands of the vocal task.

• Diagnosis of ADSD often requires some evidence of voice improvement with…

– (1) Emotional vocalization (laughing, crying)

– (2) Falsetto or Singing

– (3) Sustained Vowels

– (4) Phonetic Context (Voiceless-laden words/sentences better).

• Two research studies to evaluate the diagnostic value of task-dependency as a means to distinguish

ADSD vs. MTD



ADSD: Task dependency & phonetic context

• Task dependency in ADSD…

– Sentences loaded with voiced segments (& lots of vowels) will

provoke (worsen) symptoms (i.e., more strain, voice breaks).

–Sentences loaded with voiceless segments will decrease symptoms

(i.e., improved performance…less strain, voice breaks).

– Voiced consonants (worse) vs. voiceless consonants (better).



Examples of “Voiced” (Voice ON) vs.

“Voiceless” (Voice OFF) Distinction

• Voiced Consonants

– Stops /b, d, g/

–

Fricatives /v,z, zh/ – Affricates /dz/

– Glides & liquids /w, r, l, j/

• Voiceless Consonants

– Stops /p, t, k/

–

Fricatives /f, s, sh, h/ – Affricates /ch/



Task Specificity- (ADSD)

• Sentences with all voiced consonants provoke moresymptoms (i.e, poorer voice with this phonetic context).

– Early one morning a man and a woman were ambling along a onemile lane running near rainy island avenue (Dedo & Shipp, 1980).

• Sentences with mostly voiceless consonants provoke fewersymptoms (i.e, better voice with this phonetic context).

– He saw half a shape mystically cross fifty or sixty steps in front ofhis sister Kathy’s house.

• (N.B. reverse pattern for ABSD)



ADSD vs. MTD: Is task-dependent sign expression

a distinguishing feature?

• Roy, N., Mauszycki, S.C., Merrill, R.M., Gouse, M. &

Smith, M. (2007).Toward improved differential

diagnosis of adductor spasmodic dysphonia and muscle

tension dysphonia. Folia phoniatrica et Logopedica,59(2), 83-90.



Participants• N = 29 ADSD (17 F, 12 M, mean 45.6 yrs)

– ADSD provisional diagnosis based on guidelines of Cannito& colleagues (Cannito & Kondraske, 1990; Cannito &Woodson, 2000)

• absence of perceptual symptoms of the classical dysarthrias,

• auditory-perceptual characteristics consistent with the disorder (evidence of phonatory breaks and a strained-strangled quality, and no obvious tremor during phonation),

• occasional moments of normal sounding voice,

•

improved voice for non-speech vocalizations,• improved voice quality for phonation at high pitch.

– no v.f. lesions

– No prior Botox at time of audiorecordings

– Therapy failure & subsequent positive response to Botox



Participants

• N = 33 MTD (28 F, 5 M, mean 46.9 yrs) – Myriad voice qualities (dyphonia not aphonia)

– No v.f. lesions

– Pain/discomfort upon palpation, stiff hyo-laryngeal sling,

elevated larynx (narrow T.H. space).

– Sustained positive response to voice therapy

(corroborated Dx).



Methods• Voice Stimuli (order randomized within & acrosss

subjects):• Early one morning a man and a woman were ambling along a one-

mile lane running near Rainy Island Avenue.

• He saw half a shape mystically cross fifty or sixty steps in front ofhis sister Kathy’s house.

• 5 graduate SLP students rated dysphonia severity

• 10 cm visual analog scale (VAS)

A. Normal Voice

B. Normal Voice

Profoundly

Abnormal VoicProfoundly

Abnormal Voic



Visual Analog Scale

1. Voiced Sentence

2. Voiceless Sentence

Normal VoiceProfoundly

Abnormal Voic



Measurement of Visual Analog Scale

VAS scale = 10 cm in length

Normal Voice Profoundly

Abnormal Voice

Based upon location of vertical mark, thissample receives a score of 7 cm



Dysphonia Severity: Voiced vs. Voiceless Sentences

0

1

2

3

4

5

6

7

8

9

10

ADSD MTD

M e a n D y s p h o n

i a S e v e r i t y ( c m

Voiced

Voiceless

* p <.0001

p = .740 Note:

Baseline

Equivalence

on All-voiced

Sentence



0

2

4

6

8

10

0 2 4 6 8 10

Mean Severity (All Voiced)

M e a n S e v

e r i t y ( V o i c e l e s s )

ADSD

MTD



Task-Specificity as a Diagnostic Marker: Sensitivity &

Specificity

• Sensitivity: proportion of correctly identified cases (ADSD subjects)

• Specificity: proportion of correctly identified non-cases (MTD

subjects).

• Receiver Operating Characteristic (ROC) curve generated using the

variable cutoff criterion to determine a case.

• E.g., 1 cm cutoff required voiceless sentence to be rated at least 1 cm

less severe than rating for voiced sentence.





0

0.2

0.4

0.6

0.8

1

0 0.2 0.4 0.6 0.8 1

1-Specificity

S e n s i t i v i t y

4 cm

3 cm

2 cm

1 cm

0 cm

-1 cm

Sensitivity = % of correctly classified ADSD casesSpecificity = % of correctly classified MTD cases

1-Specificity = % of false positives (i.e., MTD’s incorrectly classified as ADSD)

“False Positives”

Worthless Test

Best

PossibleTest

Receiver Operating Characteristic (ROC)

Curve



Conclusions

•

ADSD is “fairly” task-specific (>1 cm) (48% sensitivity)• MTD is not task-specific (88% to 100% specificity, as size of

difference increases 1 cm to 4 cm)

• Clinical Implications: –

If don’t observe task-specificity, can’t rule out ADSD (look for otherconfirmatory signs/symptoms).

– But, if observe task-specificity (1) likely ADSD, (2) can rule out MTD,especially as size of difference increases.

– Clinicians must survey/employ specific voice stimuli duringdiagnostic session, otherwise miss important distinguishing features

(i.e., task-specificity).



Further Research on Task-Specificity in ADSD and

MTD

Assertion # 2:• In ADSD, the dysphonia during sustained vowel production (i.e., vowel

prolongation) is less severe (normal?) as compared to connected speech.

• Sustained Vowels vs. Connected Speech?

• Roy, N., Gouse, M., Mauszycki, S., Merrill, R., & Smith, M.(2005). Task-specificity in adductor spasmodic dysphoniaversus muscle tension dysphonia. The Laryngoscope, 115(2), 311-316.



Participants

• ADSD (n=36)• MTD (n=45)

• Same criteria for inclusion as previous study.

•Subjects recorded producing either connectedspeech- Rainbow Passage (Fairbanks, 1960) or a

sustained vowel “ah”.



Methods

• Voice Stimuli (order randomized within & acrosss

subjects):

• Sustained Vowel “ah” (three seconds)

• “these take the shape of a long round arch with its path high

above, and its two ends apparently beyond the horizon”.

• 5 graduate SLP students rated dysphonia severity

• 10 cm visual analog scale (VAS)

A. Normal Voice

B. Normal Voice

Profoundly

Abnormal VoicProfoundly

Abnormal Voic

k f



Task Specificity?

Sustained Vowels vs. Connected Speech

0

2

4

6

8

10

MTD ADSD

M e a n D y s p h o n i a S e v e r i t y ( c m ) Connected Speech

Sustained Vowel

p =.001**p =.707 Baseline

Equivalence

on C.S.



Conclusions

•

ADSD is “fairly” task-specific (>1 cm) (53% sensitivity)• MTD is not task-specific (76% to 93% specificity, as size

of difference between sustained vowel and connectedspeech increases from 1 cm to 4 cm)

• Clinical Implications:

– If don’t observe task-specificity, can’t rule out ADSD

– But, if observe task-specificity (1) likely ADSD, (2) as size ofdifference increases between sustained vowel and connectedspeech, very unlikely that it is MTD.



Assertion #3

• Response to lidocaine block of the RLN predictsresponse to subsequent RLN sectioning (Dedo,

1976), and confirms/corroborates the diagnosis of

ADSD.



Lidocaine Block of the RLN?

• Dedo (1976) offered presurgicalRLN Block in ADSD as a means todetermine surgical candidacy, andto predict possible response to RLNsection. A positive response to RLNBlock was advocated as a necessaryprerequisite to RLN sectioning.

• We reasoned that a positiveresponse to lidocaine block of theRLN in ADSD might offer promise as

a potential diagnostic test, not topredict response to RLN sectioning,but to distinguish ADSD from MTD.



Roy, N., Smith, M.E., Allen, B., Merrill, R. (2007). Adductor spasmodicdysphonia versus muscle tension dysphonia: Examining the diagnostic

value of recurrent laryngeal nerve lidocaine block. Annals of Otology,Rhinology, and Laryngology , 116(3), 161-168



Participants

•

N = 23 ADSD (14 F, 9 M; M=44.8 yrs, SD=12.6) – ADSD provisional diagnosis based on guidelines of

Cannito & colleagues (Cannito & Kondraske, 1990;Cannito & Woodson, 2000)

–

No tremor, no v.f. lesions – No prior Botox at time of audiorecordings

– Therapy failure & subsequent positive response to Botox



Participants

•N = 20 MTD (16 F, 4 M; M=43.6 yrs, SD=15.9) – No v.f. lesions

– Pain/discomfort upon palpation, stiff hyo-laryngeal sling,

elevated larynx (narrow T.H. space).

– Sustained positive response to voice therapy

(corroborated Dx).



Procedures(1) Participant audiorecorded reading the sentence… “Early one morning

a man and a woman were ambling along a one-mile lane running nearRainy Island Avenue” (Dedo & Shipp, 1980).

(2) Participant self-rated voice on three parameters (overall severity,

vocal effort, laryngeal tightness using a 10-point equal appearing

interval scale, 1= no problem, and 10= extreme problem).

(3) Participant then underwent RLN lidocaine block procedure (2.5- 5 cc’sof 1% lidocaine deposited in right neck using a 27 gauge needle;

complete R. vocal fold immobility was confirmed laryngoscopically).

(4) During the RLN block condition the participant’s voice was re-

recorded and self-ratings re-administered.



Lidocaine Block of the RLN



Results- Patient-Based Ratings (Pre vs. During

OVERALL SEVERITY

1

2

3

4

5

6

7

8

9

10

ADSD MTD

Group

S e v e r i t y

Pre Block

During Block

p <.002 p <.034

OVERALL EFFORT LEVEL

1

2

3

4

5

6

7

8

9

10

ADSD MTD

Group

S e v e r i t y

Pre Block

During Block

p <.0001 p <.020

LARYNGEAL TIGHTNESS

1

2

3

4

5

6

7

8

9

10

ADSD MTD

Group

S e v e r i t y

Pre Block

During Block

p <.0001 p <.006



Methods: Auditory-Perceptual Evaluation of

Audiorecordings

• Sentence Stimuli (order randomized across & within subjects, andpre/during block presented as a set):

– Early one morning a man and a woman were ambling along a onemile lanerunning near Rainy Island Avenue

• 6 blinded, graduate SLP students rated pre/during block samples

• 10 cm visual analog scales (VAS) – (1) overall dysphonia severity,

– (2) breathiness,

– (3) strain



Visual Analog Scale (Pre/During Block)

No Breathiness

Normal VoiceExtremely

Abnormal Vo

Extreme

Strain No Strain

Extreme

Breathine

Listener Ratings (Pre vs During Block)



Listener Ratings (Pre vs. During Block)

OVERALL SEVERITY

0

20

40

60

80

100

ADSD MTD

Group

S e v e r i t y

Pre Block

During Block

p <.013 p =.338

BREATHINESS

0

20

40

60

80

100

ADSD MTD

Group

S e v e r i t y

Pre Block

During Block

p <.002 p =.178

STRAIN

0

20

40

60

80

100

ADSD MTD

Group

S e v e r i t y

Pre Block

During Block

p <.0001 p <.003

Positive response to RLN Block as a Diagnostic Marker:



Positive response to RLN Block as a Diagnostic Marker:

Sensitivity & Specificity

•

Sensitivity: proportion of correctly identified cases (ADSD subjects)

• Specificity: proportion of correctly identified non-cases (MTDsubjects).

• Receiver Operating Characteristic (ROC) curve generated using thevariable cutoff criterion to determine a case.

• E.g., 1 cm cutoff required during block sample to be rated at least 1 cmless severe than rating for pre-block sample.





ROC Curves

OVERALL SEVERITY

0

20

40

60

80

100

0 20 40 60 80 100

1-Specificity

S e n s i t i v

i t y

>1cm

>3cm

>2cm

>4cm

>5cm

BREATHINESS

0

20

40

60

80

100

0 20 40 60 80 100

1-Specificity


>1cm

>2cm

>3cm

>4cm

>5cm

STRAIN

0

20

40

60

80

100

0 20 40 60 80 100

1-Specificity


>1cm

>2cm

>3cm

>4cm

>5cm



Conclusions

•

Both ADSD and MTD respond favorably to RLN Block.• Estimates of Sensitivity and Specificity, and ROC plots

confirm that positive response to RLN block is a poor(i.e., worthless) diagnostic test, and should not be usedas a means to distinguish ADSD from MTD (Dedo,

1976?).• Important for clinicians (ENTs, SLPs, Neurologists) to

know the precision or imprecision of the tests they use,avoid misdiagnosis!!!

A ti #4



Assertion #4

• Phonatory Breaks are the sine qua non of ADSD (Sapienza,

Walton, & Murry, 2000; Rees, Blalock et al., 2008; Ludlow,

1995)

All-voiced sentence- ADSD

R h Q ti



Research Questions

•

Do subjects with ADSD and MTD demonstrateacoustic evidence of phonatory breaks?

• Are phonatory breaks specific to ADSD?

• Using conventional estimates of diagnostic precision,

what is the clinical utility of phonatory break

analysis as a diagnostic test to distinguish ADSD from

MTD?



Acoustic Analysis

• Phonatory Breaks (ADSD vs. MTD) – Frequency, duration?

“Mile”



• Roy, N., Whitchurch, M., Merrill, R., Houtz,

D., Smith, M. (2008). Differential diagnosis of

adductor spasmodic dysphonia and muscle

tension dysphonia using phonatory break

analysis. The Laryngoscope, 118(12), 2245-

2253.

Participants



Participants

•

41 subjects with ADSD (19 males, m = 47.42 years,SD = 11.96 years; 22 females, m = 50.00, SD = 13.99).

• 59 subjects with MTD (10 males, mean age

[m] = 49.20 years, standard deviation [SD] = 15.94

years; 49 females, m = 48.47, SD = 15.76)

Procedures



ProceduresVoice Stimuli• Each participant was recorded reading an all-voiced consonant sentence:

Early one morning a man and a woman were ambling along a one-milelane running near Rainy Island Avenue (Dedo & Shipp, 1980).

Phonatory Break Analysis•

the presence, frequency, and duration of any within-word phonatorybreaks were measured.

• A phonatory break consisted of a complete absence of phonation.

• The absolute duration of the phonatory break was measured inmilliseconds by marking the initiation of the break with the last clearpositive glottal pulse and termination of the phonatory break with the first

clear positive glottal pulse at the return of phonation.

Phonatory Breaks ADSD vs MTD?



Phonatory Breaks ADSD vs. MTD?

Initiation of phonatory break Termination of phonatory break

Initiation of phonatory break Termination of phonatory break

Phonatory break from a patient with ADSD on

the word ‘avenue’ measuring 256.33 ms

Phonatory break from a patient with MTD on the

word ‘avenue’ measuring 84.98 ms

General Results



General Results

• Both ADSD and MTD showed evidence ofphonatory breaks.

• Subjects with ADSD displayed significantly more

breaks than subjects with MTD.

• Information regarding both duration and number

of phonatory breaks improves diagnostic

precision

Results



Results

•

According to indices of diagnostic precision, patients withMTD (regardless of gender) will almost never have more

than four phonatory breaks in the single all-voiced sentence

(95% specificity).

• Women and men with MTD displayed different patterns.

• Men with MTD infrequently showed breaks, and never

showed acoustic evidence of 2 or more phonatory breaks

(regardless of duration).

Relationship among terms, and how each indicator of



Reference/Gold Standard

T e s t O u t c o m

e

“Have ADSD” “Have MTD”

Positive Test

(i.e., Evidence of Phonatory Breaks)

A

True positives

B

False Positives

Negative Test

(i.e., No evidence of Phonatory

Breaks)

C

False negatives

D

True negatives

•Sensitivity = A / (A + C)

•Specificity = D / (B + D)

•PV+ = A / (A + B)•PV – = D / (C + D)

•LR+ = sensitivity / (1 – specificit

•LR – = (1 – sensitivity) / specifici

diagnostic precision is calculated.

Conclusions re Phonatory Breaks



Conclusions re: Phonatory Breaks

•

Phonatory break analysis offers promise as a diagnostictest to distinguish ADSD from MTD, and is especially

useful in males.

• Information regarding “number” of phonatory breaks

improves diagnostic precision in both men and women.

• In the future, automated phonatory break analysis of an

all-voiced stimulus sentence, like the one used in this

study, could represent an important step toward

improved diagnostic precision.

Summary of the Evidence?: Distinguishing SD and MTD



Summary of the Evidence?: Distinguishing SD and MTD

• Little evidence of task specificity in MTD. – MTD’s sustained vowel often commensurate with connected

speech.

– No obvious difference between voiced and voiceless contexts

(All contexts difficult).

• Phonatory breaks occur in both ADSD and MTD, but

more frequent in ADSD (especially males).

• Lidocaine Block of the RLN is a worthless diagnostic test

ADSD…Task Specificity (More tasks)



ADSD…Task Specificity (More tasks)

• Compare repeated productions of /wi/ vs. /pi/, /ti/, /ki/. ADSD worse on /wi/ (i.e.,

more strain, effort, voice breaks). Improvement on syllable reps. with voicelessconsonants.

• Compare rapid “ah, ah, ah” vs. “hah, hah, hah”- ADSD improved on “hah”

• Counting “Eighty series”, e.g., eighty, eighty-one, eighty- two… eighty-nine (vowelonsets difficult).

• Sixty-series… (improved performance, less strain, effort as compared to 80’s).

• Pitch-glide: Low to high (Asymptomatic in highest pitches).

• Falsetto (Counting to ten): Asymptomatic/Improved compared to C.S. @NPNL.

• Singing Happy Birthday: Asymptomatic especially when sung in highest pitch.

• Whisper: Asymptomatic

• “Islands of Normal Speech” (few words)… free of strained-strangled quality… short-lived, transient… especially after spontaneous laugh.

Conclusions



Conclusions

• No single diagnostic test/marker.

• Important for clinicians to survey a variety of speechtasks to reveal/provoke task dependent signexpression

– Ensure proper diagnosis and selection of appropriatetreatments for both MTD and SD (subtypes).

• Future research to examine discriminatory value of:

– Falsetto, singing, palpation, and improved diagnosticprecision of combining multiple diagnostic markers?

Abductor SD (ABSD)



Abductor SD (ABSD)

•

Rare form (10% of laryngeal dystonia)• Abduction of vocal folds (devoicing gesture)

• Prolonged voiceless consonants (long VOT): difficultywith voice onset following voiceless sounds e.g. /h, s, f,p, t, k/. Especially noticeable when attempting to turn

voice on after “h” as in happy.• Breathy voice quality, ? normal vowels (except in very

severe cases).

• Whispering dysphonia (aphonia)… some debate re:psychogenic aphonia (severe MTD?).

Abductor SD: Task Specificity



Abductor SD: Task Specificity

•

Sentences with all voiced segments…observeimproved performance

– Early one morning a man and a woman were ambling

along a one mile lane running near Rainy Island

Avenue. – Albert eats eggs every Easter early in the a.m.

– We mow our lawn all year.

– We rode along Rhode Island Avenue.

Abductor SD- Task Specificity



Abductor SD Task Specificity

•

/Pi/, /ti/, and /ki/ worse than /wi/• “hah, hah, hah” worse than “ah, ah, ah”

• Sixty-series more difficult than eighty series.

• Like ADSD, all other voicing tasks are easier than

connected speech i.e., sustained vowels, falsetto,

singing, laughing.

• No pain



• SD vs. MTD… You

be the judge!

• Video Case

Examples.

References



• Roy, N. (2010). Differential diagnosis of muscle tension dysphonia and spasmodic dysphonia. Current Opinion in Otolaryngology-

Head and Neck Surgery , 19, 182-187.

•

Roy, N., Whitchurch, M., Merrill, R., Houtz, D., Smith, M. (2008). Differential diagnosis of adductor spasmodic dysphonia andmuscle tension dysphonia using phonatory break analysis. The Laryngoscope, 118(12):2245-53.

• Roy, N., Smith, M.E., Allen, B., Merrill, R. (2007). Adductor spasmodic dysphonia versus muscle tension dysphonia: Examining the

diagnostic value of recurrent laryngeal nerve lidocaine block. Annals of Otology, Rhinology, and Laryngology , 116(3), 161-168.

• Roy, N., Mauszycki, S.C., Merrill, R.M., Gouse, M. & Smith, M. (2007).Toward improved differential diagnosis of adductor

spasmodic dysphonia and muscle tension dysphonia. Folia phoniatrica et Logopedica, 59(2), 83-90.

• Smith, M.E., Roy, N., & Wilson, C. (2006). Lidocaine block of the recurrent laryngeal nerve in adductor spasmodic dysphonia: A

multidimensional assessment. The Laryngoscope, 116, 591-595.

• Roy, N., Gouse, M., Mauszycki, S., Merrill, R., & Smith, M. (2005). Task-specificity in adductor spasmodic dysphonia versus muscl

tension dysphonia. The Laryngoscope, 115 (2), 311-316. 47.

• Roy, N., Ford, C.N., Bless, D.M. (1996). Muscle tension dysphonia and spasmodic dysphonia: The role of manual laryngeal tensio

reduction in diagnosis and management. Annals of Otology, Rhinology and Laryngology , 105 (11), 851-856.

Documents

3. Differential Diagnosis MTD vs SD