What is Spasmodic Dysphonia / Laryngeal dystonia?
Spasmodic dysphonia (SD) is a type of dystonia – a neurological disorder which causes abnormal movements. Spasmodic dysphonia affects movements of the vocal folds causing difficulties with speech. It is now referred to as laryngeal dystonia (LD). There are two main types of laryngeal dystonia (LD). Adductor laryngeal dystonia (AdLD) makes up about 85% of cases and causes the vocal folds to come together inappropriately during speech. Abductor laryngeal dystonia (AbLD) makes up around 13% of cases and causes the vocal folds to inappropriately spread apart during speech. In rare cases some people can have a mix of the two conditions.
Laryngeal dystonia usually starts between the ages of 30 and 50. It is more common in women but can also occur in men. It is usually not hereditary but some people have a family history of other dystonias. The cause is unknown and there are no known dietary or environmental factors which increase the risk of developing the condition.
What are the symptoms of Spasmodic dysphonia / laryngeal dystonia?
laryngeal dystonia presents with difficulty speaking. Affected people typically have trouble especially speaking in background noise or when using the phone. Adductor laryngeal dystonia causes a strangled and strained type of voice because the vocal folds are coming together too tightly. Abductor laryngeal dystonia causes a breathy and whispery type voice especially for the second part of many words because the vocal folds are coming apart during speech causing air to leak out.
Laryngeal dystonia tends to be task specific – i.e. affects the speaking voice. People typically find that they are able to voice more easily when they sing or speak in a foreign accent. Some people find that the voice fluency improves temporarily with alcohol however this is not recommended as a treatment. Some people have associated tremor and a small percentage of people have other types of dystonia or movement disorder.
A rarer form of laryngeal dystonia affects the function of breathing (adductor laryngeal breathing dystonia). Affected people experience difficulty breathing in or noisy inspiration because the vocal cords close instead of open when they breathe in thus narrowing the airway.
The symptoms tend to fluctuate from day to day. Anxiety and stress tend to make the problem worse and people tend to experience more difficulty when public speaking.
What is the treatment for Spasmodic Dysphonia / laryngeal dystonia?
Currently there is no known cure for laryngeal dystonia.
Speech Therapy – Can help people with their communication and provide voicing strategies. Often a trial of speech therapy is indicated prior to embarking upon more invasive treatments because some conditions which present with symptoms similar to laryngeal dystonia will respond to speech therapy.
Medical Treatment – A type of medicine which weakens the vocal cord muscles in order to reduce inappropriate opening or closing activity can be delivered to the voice box via a small needle. This can be done simply and quickly in a specialised clinic and is well tolerated in the majority of cases. In Adductor Laryngeal Dystonia; because the closing muscles are weakened, the treatment is often followed by 7-10 days of a breathy voice after which the voice tends to smooth out and improve. The improvement in voice usually lasts 10-12 weeks before a repeat injection is required. This is currently the most commonly used treatment for laryngeal dystonia by medical specialists treating the condition and remains the ‘gold standard’ of treatment.
Surgical Treatment – Some people have reported success in treating LD by altering the nerve supply to the vocal cords. Initial results are often promising but due to the complex nature of the condition the problem often returns worse than before 12 months or more after surgery. Surgery is currently a last resort treatment reserved for those with severe functional impairment in whom medical treatment is unsuccessful
Do you treat Spasmodic Dysphonia / Laryngeal dystonia?
A/Prof Novakovic and Dr Stewart trained in the USA under Dr Andrew Blitzer who is considered one of the worlds foremost experts in laryngeal dystonia and actually pioneered and performed the world’s first injection treatment for this disorder over 25 years ago. Both doctors are experienced in the diagnosis and treatment of patients with all voice disorders including laryngeal dystonia. A/Prof Novakovic has also published journal articles and textbooks on the topic.
At our St Leonards clinic we are able to administer treatment for laryngeal dystonia using EMG (electromyographic) guidance to ensure optimal accuracy. Please contact us for further information or an appointment