TREATMENT OPTIONS

There are no medications that are designed specifically to correct spasmodic dysphonia. There are medications that can help dystonia in general and occasionally SD patients can also benefit but usually the side-effects (drowsiness) are worse than the benefits. Patients can speak directly to their physician to see if any medications would benefit them. Most often it is impossible to know without ‘a try it and see approach’.

Botulinum toxin (marketed as Botox) is the most power poison in the world. In it purified form, a very small amount injected into any muscle will weaken it for several months. The muscles controlling the vocal cords are pathologically tight and in spasm as a result of the neurological disorder of spasmodic dysphonia (SD). One therapy, therefore, is to deliberately weaken the muscles controlling the vocal cords with targeted injections of Botox. The muscles are then weaken for several months and this reduces the severity of the symptoms. The downsides of Botox include (i) a weaken or ‘breathy’ voice, (ii) the effect is only temporary and must be repeated for ever, (iii) the needle injections through the throat are painful, and (iv) it can be very expensive.

The goal of all of these various types of destructive surgery is similar to that following Botox – weaken or disable the affected muscles. They have only been used on a subtype of SD called adductor spasmodic dysphonia.

Thyroplasty is an operation where the vocal cords are moved further apart. That way, when the SD forces them closed, there is still a small space between the vocal folds. A review of this technique reported short term benefits with two-thirds of patients returning to baseline within one year. Denervation operations involve cutting the nerve(s) to the vocal cords. This produced a ‘hoarseness’ instead of SD but many patients have a return of their symptoms once the nerve regenerates. Selective Laryngeal Adductor Denervation-Rennervation (SLAD-R)is a type of denervation procedure but the cut nerves are attached to different, nearby nerves.

The original report from 1999, described 21 patients who were reported to do well although the outcome was a telephone survey and the opinion of an expert who clearly knew if the patients had received surgery or not. This raised the possibility of bias. Six patients had complications and four required additional surgery or therapy. No measure of the expected complication, voice breathiness, was provided.

A long-term, retrospective follow-up of some of the patients who had this procedure reported chronic breathiness in 30% and continued voice breaks in 26%. Unfortunately, this surgery has not become widely accepted and only one other center (Vancouver) has ever reported their experience with SLAD-R.