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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 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.