Spasmodic Dysphonia

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Transcript Spasmodic Dysphonia

Spasmodic Dysphonia
A severe hyperadductive
voice disorder
The many faces of SD….
Lalophobia
Psychophonasthenia
Mogiphonia
Apthongia
Stammer of the VF
Phonatory Glottal Spasm
Spastic Dysphonia
What is Spasmodic
Dysphonia?
A rare voice disorder affecting approx..
50,000 people in the USA
“spasms” of the vocal folds that cause
interruptions of voicing
requires considerable effort to phonate
frequently misdiagnosed (Aronson, 1968,
Brin, 1991)
Dystonia?
Specific cause of SD is unknown;
considered to be a neruologic condition:
dystonia.
Dystonia is a syndrome dominated by
sustained muscle contractions frequently
causing twisting and repetitive
movements, or abnormal postures that
may be sustained or intermittent
During speech, the laryngeal muscles
over-contract so the voice is produced
with excessive effort and force.
Dystonic movements are rapid and
repetitive; voice will be strained,
strangled, tremulous or intermittently
breathy
Suspected Cause of SD
Appears during adulthood but can start at
anytime; symptoms most frequently occur
in the 4th or 5th decade
Cause is unknown but there is usually a
sign or symptom of another Dsytonia in
the body (genetic predisposition?)
Rosenfeld (1990) reported a link between
onset of SD and virus/bacteria
Cause, cont..
Trauma may trigger the onset
Medication: phenthiazines known to cause
dystonias
Brin (1991) possibly a link in chromosome
9
symptoms are thought to be the result of
functioning in the basal ganglia; BG
coordinates movements througout the
body
Forms of SD
Adductor
most common
Abductor
sudden aphonic episode
Mixed adductor/abductor
Essential Tremor??
More…..
Many forms of dystonia:
belpharospasm (eyelids)
torticollis (neck)
SD is a focal (isolated) dystonia that
involves one small group of muscles in
one area of the body: the larynx
Most dystonias are “action induced” e.g.,
larynx is normal at rest, not during
speaking
Etiologic Theories
Psychogenic Origin
1st described by Traube (1871) as a
hysterical illness
tx included psychotherapy, acupuncture,
hypnosis, biofeedback, drug treatment
Neurologic: physical cause 1st suggested
by Schnitzler (1875), a Viennese
laryngologist
Combination??
Treatment of SD
Botulinum Toxin (BOTOX) injection
Recurrent Nerve Section
Traditional therapies
Recurrent Laryngeal Nerve
Section
Dedo and Shipp: resected the RLN to
resolve the hyperadductive spasm, e.g,
unilateral cord paralysis would diminish
the symptoms
over a 5 year period, 40-50% of patients
had a relapse of symptoms
Botulinum Toxin
“BOTOX” is a protein produced by the
bacterium Clostridium Botulinum; it is
literally nature’s most powerful poison.
Effect is to to inhibit the synapse along
the neuromuscular junction so that the
overcontraction of laryngeal muscles is
diminished
it blocks acetylcholine; leads to musc.
weakness
BOTOX, cont..
Very small amounts are injected into the
thyroarytenoid; effect is to reduce the
spasm
the effect is temporary as the axons resprout to form new neuromuscular
junctions
effect produces reduced or eliminated
voice symptoms (Ludlow, 1990 & Simon,
1990)
Toxin lasts about 3-4 months
BOTOX “side effects”
Temporary voice breathiness,
weak vocal intensive (decreased
loudness)
transient difficulty with swallowing liquids
(Brin, 1993)
BOTOX therapy (Bastian,
1994)
Initial Wait: no change in voice for initial
1-2 days post injection
spasms diminish on about the 3-4 days
voice may vary during this time
Weak-breathy voice phase: voice is weak,
breathing is inefficient for sph; some pts.
Will cough on liquids
Bastian, cont..
“Talking is golden” phase: 1-3 months
after the weak-breathy phase ends; voice
can be completely normal
“Spasms are back” phase: during the 2nd
to 4th month, some symptoms re-appear;
not immediate need but consult a
calendar to consider the next injection
FAQs
No 2 injections are alike even if dose and
technique are the same. Maybe be due to
small, unavoidable differences in needle
placement
Individual differences: individual
sensitivity to medication, absorption rate,
etc.
Unsatisfactory response: consider
alterations in the technique, dosage,
timing, etc.