Title: Spasmodic Dysphonia
1Spasmodic Dysphonia
2- Spasmodic Dysphonia is primarily characterized by
frequent voice breaks and significant vocal
effort
3Spasmodic Dysphonia (SD)
- Controversial etiology
- Psychologic vs. neurologic
- SD is generally considered an
- adult onset action induced focal dystonia
4What is a focal dystonia?
- Uncontrolled spasmodic muscle contractions
- Often begin in adulthood
- May be
- restricted to a few muscles (focal)
- Segmental (group of muscles)
- General (large areas of the body)
- Problems typically occur during task execution
and appear normal at rest
5Other Examples of Focal Dystonia?
- Blepharospasm
- Writers cramp
- Torticollis (cervical dystonia)
6Evidence for a neurogenic etiology for SD
- Pts often exhibit other movement related problems
(limb, orofacial) - Non-medical treatment meets only limited success
- Limited evidence for neurologic differences
between SD and normal population - Variety of neural loci implicated
- basal ganglia, SMA
7Potential Neural Mechanisms
- Reduced neural inhibition
- Increased neural plasticity
- Abnormal sensory gating
8Spasmodic Dysphonia Other Observations
- Symptoms may increase during stress
- More likely to have had childhood measles/mumps
- No more likely to have other neurological
conditions - No obvious environmental patterns
- More common for those with European ancestry
- 10 report a family history
9Spasmodic dysphonia Types
- Adductor SD (ADDSD)
- Intermittent voice breaks in the middle of vowels
- Strained-strangled, effortful voice quality
- Spasmodic hyperadduction of TVFs
- Abductor SD (ABDSD)
- Abduction of true vocal folds (devoicing gesture)
- Prolonged voiceless consonants difficulty with
voice onset following voiceless sounds - May have breathy voice quality
10Vocal Tremor
- voice breaks, frequency modulation or amplitude
modulation at regular intervals (5 Hz) - Best observed during a sustained vowel task
- Tremor is a common neurologic sign
- Tremor therefore is highly suggestive of neural
involvement - May be associated with known neurological disease
- May be familial
- Can occur as an isolated condition
- Often co-occurs with SD ( ¼ of SD have tremor)
11(No Transcript)
12Spasmodic Dysphonia Related Disorders
Epidemiology
- Prevalence of focal dystonia 295 per million
- Prevalence of SD 1 per 100,000
- Prevalence ranking for focal dystonia
- Torticollis
- Blepharospam
- SD
- Females gt Males
- ranges from 1.41 71
- ABSD less common
- 10-15 of SD
13Spasmodic Dysphonia diagnostic tasks
- Connected speech-will exhibit difficulties
- Sustained vowel
- Reduction/resolution of symptoms
- less severe than connected speech
- May have tremor 5 Hz
- Falsetto (count to 10) - Asymptomatic
- Whisper (count to 10) - Asymptomatic
- Singing (Happy Birthday) Improvement
- Pitch glide - ? symptoms at highest pitches
- Loud speech - ? symptoms for shouting
14Adductor SD diagnostic tasks
- Sentences all voiced
- ? difficulty
- Sentences high frequency voiceless
- ? difficulty
- Eighty series (e.g. count 80, 81, 82)
- ? difficulty
- Sixty series (e.g. count 60, 61, 62)
- ? difficulty
- repetitions of we vs. pea, tea, key,
see - we ? difficulty
15Abductor SD diagnostic tasks
- Sentences all voiced
- ? difficulty
- Sentences high frequency voiceless
- ? difficulty
- Eighty series (e.g. count 80, 81, 82)
- ? difficulty
- Sixty series (e.g. count 60, 61, 62)
- ? difficulty
- repetitions of we vs. pea, tea, key,
see - voiceless ? difficulty
16ADSD vs. ABSD Sentence Stimuli
- All voiced segmentselicits ADSD symptoms
- 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.
17ADSD vs. ABSD Sentence Stimuli
- Voiceless segmentselicits ABDSD symptoms
- He saw half a shape mystically cross fifty or
sixty steps in front of his sister Kathys house. - She sells seashells by the seashore.
18ADSD Other diagnostic tasks
- Ingressive reading of all voiced segments
- Unilateral RLN Block (lidocaine)
- Will eliminate ADDSD within several minutes of
ipsilateral paresis/paralysis - lasts about 20-25 minutes
- Should confirm paralysis endoscopically
- Return of pre-block symptoms after nerve block
effects abate - Recent evidence suggests this does not
differentiate ADSD from MTD (Roy, et al. 2007)
19Other signs/symptoms of ADDSD
- Minimal signs of ? musculoskeletal tension
- Minimal pain, tenderness, hypertonicity
- Laryngeal elevation is in synchrony with adductor
spasms - No sustained response to manual circumlaryngeal
techniques (behavioral treatment) - Some transient improvement with laryngeal
stabilization maneuvers (behavioral treatment)
20Distinguishing SD and MTD
- MTD
- Severity of sustained vowel often commensurate
with connected speech - No obvious differences between voiced and
voiceless contexts (all contexts difficult) - Is usually continuous and rarely intermittent (no
islands of normal speech) - Shows no improvement with falsetto or singing
21Distinguishing SD and MTD
- MTD
- Is associated with reported pain, tenderness
- Is not associated with tremor
- Shows sustained improvement after manual
circumlaryngeal therapy
22Distinguishing SD and MTD
- Studies of psychologic factors and dysphonia
- MTD
- tendency toward introversion and neuroticism
- SD
- No evidence for psychological/personality factors
- There is evidence pre-post differences that may
be related to a reaction to the problem
23Recent evidence
- If there is not a voiced-voiceless difference in
severity, it does not necessarily exclude ADSD
from the Dx (1/2 ADSD did not show task
specificity in recent study) - If there is a voiced-voiceless difference in
severity, the likelihood of ADSD is increased
24Spasmodic Dysphonia Management
- No known cure
- Treatment aim is to control/relieve symptoms
- Patient should be educated regarding management
options - Advantages/disadvantages with all treatments
25Spasmodic Dysphonia Treatment options
- Behavioral
- Voice Therapy (limited benefit for moderate to
severe ADDSD or tremor) - Medical
- Botulinum Toxin injections (BOTOX)
- Neuropharmacological Intervention
- Surgical
- Recurrent Laryngeal Nerve Section
- Thyroplasty, myotomy etc.
26When/Who to offer voice therapy?
- During differential diagnosis (diagnostic
therapy) - Coexisting muscle tension dysphonia
- May extend the effect of BOTOX in ADDSD
- ABSD pts who exhibit little response to BOTOX
- Pts with mild/inconsistent symptoms of ADDSD
- BOTOX may provide too great an effect
- Trial therapy should be short term (lt 5 sessions)
27Possible Voice Therapy Techniques
- Manual circumlaryngeal therapy
- Breathy voice attack
- Pitch elevation
- Loudness reduction
- Techniques for hyperfunctional voice disorders
- resonant voice, yawn sigh, relaxation
- Inhalation voice therapy
28Medical Management BOTOX Injections
- Inject intrinsic muscles with BOTOX
- BOTOX neurotoxin that produces chemical
denervation at neuromuscular junction - Advantages
- Temporary
- no (known) permanent injury
- Side effects are temporary
29Botulinum Toxin (BOTOX)
30Medical Management BOTOX Injections
- Disadvantages
- Temporary
- Costly re-injection every 4 mos.
- Breathiness (7-20 days)
- Swallowing side effects (3-5 days)
- Poor predictability of patient response
- Possible buildup of resistance to injections
31Medical Management BOTOX Injections
- Who benefits most?
- Moderate to severe ADDSD
- Vocal tremor
- ABSD ?
- Patients who get questionable benefit
- Mild ADDSD
- Coexisting regional dystonia
32BOTOX Injections Procedures
- Peroral
- Injection via oral cavity
- Uses less toxin
- No EMG verification
- Percutaneous
- Through the neck tissue
- Uses EMG verification
33BOTOX Injection Sites
- ADDSD
- TA (most frequent)
- LCA
- Both
- ABSD
- PCA
- must be percutaneous
- technically demanding
- Maybe CT
- Vocal tremor
- TA, sternohyoid and thyrohyoid
- injections more likely bilateral
34BOTOX Injection Dosage
- Bilateral
- 2.5 units per side
- Unilateral
- 15 units
- Unilateral considered superior, with longer
lasting effects
35Surgical ManagementRecurrent Nerve Resection
- Advantages
- Potential long term benefit (40)
- Disadvantages
- Unpredictable side effects
- Symptom return (up to 60)
- Permanent unilateral paralysis
- Controversial
- Patient types benefited
- Focal severe ADDSD
36Other Neurpharmacological Intervention
- Propanolol (Inderal) for voice tremor
- Artane (anticholinergic) for ABSD
- Baclofen muscle relaxant for ADDSD
- Disadvantages
- Limited voice change
- Adjunct role at best
- No controlled studies to demonstrate effectiveness
37Selected CNS diseases
- ALS
- Parkinsons Disease
- Myasthenia gravis