Spasmodic Dysphonia - Brain Disorders A-Z

What is Spasmodic Dysphonia?

Spasmodic Dysphonia (SD) is an uncommon voice disorder which has a significant impact on the quality of life of the sufferer. It is classified as a dystonia, which is a task-specific neurological movement disorder. Involuntary contractions of the muscles of the larynx occur during specific vocal activities such as speaking but not during laughing or yawning. Spasmodic Dysphonia is sometimes called laryngeal dystonia.

Dystonia is a disorder of movement, which need not involve any other functions of the brain. Thus intellect, personality, memory, emotions sight, hearing and sensation are all quite normal in people with Spasmodic Dysphonia.

Most frequently, it causes involuntary closure of the vocal cords, which results in effortful speech with a tight, strained/strangled quality and abrupt breaks in voicing (adductor SD). There is a rarer form of Spasmodic Dysphonia where the vocal cords open involuntarily during speech causing intermittent breathiness (abductor SD).

SD affects men and women of all ages, in all walks of life. Interruption of free flowing speech can profoundly influence social and professional interaction and emotional well-being, and cause feelings of isolation and despair.

What Causes Spasmodic Dysphonia?

The cause of Spasmodic Dysphonia remains undetermined, but it is often triggered by stress or illness. Research suggests that a chemical imbalance in the basal ganglia, an area of the brain involved in coordinating movements of muscles throughout the body, is responsible for SD. As with other dystonias, fatigue or stress tends to make the problem worse.

What Research is Being Done?

The ultimate goals of research are to discover the cause of SD so that the disorder can be prevented and to find a cure or improved treatment method for people affected. Scientists are exploring better treatments and testing to see how to extend the benefit from current therapies for SD.

How is it Diagnosed?

SD is rare and symptoms can be confused with a number of voice disorders. Accurate diagnosis requires assessment by a Speech Pathologist, Ear Nose & Throat Specialist and a Neurologist experienced in the management of SD.

What Can Be Done For People With Spasmodic Dysphonia?

Firstly, an accurate diagnosis is essential. This in itself reduces frustration and anxiety and opens up several treatment options. After performing a detailed laryngeal examination, the Ear Nose & Throat Specialist refers people with SD for further management.

The Speech Pathologist is involved in assessment, diagnosis and treatment of SD and will provide information, encouragement and ideas to help people manage more effectively. Voice therapy can be beneficial for some people with SD and has been shown to prolong the effects of Botulinum toxin through reducing compensatory speech patterns (Murry and Woodson, 1995). As most people find that their symptoms are aggravated by stress and fatigue, stress management or relaxation therapy may help some people to cope more easily with their symptoms.

The Neurologist may trial certain medications where appropriate, or administer local injections of Botulinum toxin.

Local injection of Botulinum toxin into the vocal cord muscles can provide significant, though temporary relief from the symptoms of SD and a marked improvement in voice quality. Botulinum toxin weakens the overactive muscles for approximately 3-4 months, after which time reinjection is necessary.

Click here for the latest Australian research papers on Spasmodic Dysphonia.