Etiology
This syndrome results from irregular contractions of the adductory muscles of the larynx. It has a range of presentations from a severely strangled voice to a mild cry like distortion of the voice. It can be mixed with ABductor SD.
Diagnosis
History
Typical complaints
- speaking is effortful
- vocal instability
- vocal unpredictability
- hate the phone
- “I can hear my own voice and its terrible”
- “I have to depend on my voice and it is not reliable”
- wavering voice
- variability of voice
- glitches
- good days and horrible days
- people ask if I have laryngitis constantly
- “I have seen several ENT doctors and they say nothing is wrong with me”
- Stress makes it worse
- May be associated with previous head trauma
Character of a patient with adductor spasmodic dysphonia
- Patients are often frustrated because of the long period of time between the onset of their disorder and the correct diagnosis.
- They may have been told in the past that their problem was psychogenic.
- The disorder is highly variable and they may indeed present on a day when their spasms are almost nonexistent.
- Talkativeness scale: whole range
Vocal capabilities
- Hear samples of ADductor spasmodic dyphonia
- Prolonged vowel phonation
- spasms interrupting voice are irregularly unsteady compared to tremor which is a regular 4 to 5 Hz fluctuation.
- Atypical spasmodic dysphonia may present with a tonic tightness to the voice without discrete spasms.
- Unsteadiness tends to improve with falsetto (tremor remains unchanged)
- Unsteadiness improves with singing and distraction.
- pulling on the tongue during rigid laryngoscopy may eliminate the spasms)
Laryngeal Exam
- rigid laryngoscope
- general unsteadiness with random contractions of supraglottis and glottis
- flexible laryngoscope
- during speech, spasms of the adductory muscles may be noted with inadvertent closure of the glottis
Treatment
Medical
- botulinum toxin injections into thyroarytenoid muscles
- Our average starting dose is 1.67 units total divided equally between each thyroarytenoid.
- My dilution schedule
- Our average dose is 2.5 units total. Our range of dosing is .3 units to 10 units total dose.
- The dose does not seem to be related to body size, age or severity of dystonia.
- Thus the first two injections are trial doses to determine the ultimate dosing schedule.
- Duration of the satisfactory effect is a median of 16 weeks with an approximate range of eight to twenty six weeks. though patients often note the first return of some effort or spasms around 12 - 14 weeks, it remains tolerable for 2 -4 weeks depending on the person.
- There is a direct correlation between size of dose and duration of effect only in the low to middle of the range of doses.
- At very low doses, an increse in dose will have in increase in effect.
- Once the effect reaches 12 - 16 weeks and the patient has started to have some initial side effects of hoarseness and/or aspiration of liquids, then the increases in dose tend not to or minimally prolong duration, mainly there is an increase in the severity and duration of the initial side effects. See the Art of an injection.
- In most cases, the farther anterior the injection, the less the medication will enter the LCA muscle and the less liquid aspiration will be a problem.
- Patient information
Surgery
- Denervation - Reinnervation surgery is a possible treatment.
- Recurrent larygeal nerve section is still used by some. I would not recommend it
- Some physicians have suggested laser debulking of the vocal folds.
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