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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?.
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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 re-sprout 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.