Spasmodic Dysphonia

Spasmodic dysphonia is a neurological disorder, characterized by the involuntary contractions of the muscles. This is one of the most common disorders in which the involuntary spasms appear when only in relation to a specific task. For example, if a person with spasmodic dysphonia tries to speak, the larynx muscles are going to involuntarily contract. This will have a negative effect on the voice, causing it to suffer different modifications. The spasms appear one after the other and they can cause interruptions in the speech or even make the voice become whispery. The paradox is that the functioning of the larynx remains normal during other activities, including breathing or swallowing.

This condition is often misdiagnosed and it affects most commonly persons who are middle aged. Women are more often affected than men and the onset of the condition is progressive, without any actual cause being identified. Even though symptoms are present, the person suffering from spasmodic dysphonia will not present any actual physical modifications at the level of the larynx. There are no nodules or lumps and there is no inflammation identified. The symptoms can become worse with the passing of time but they will reach a point at which they remain stable. Brief periods of remission are rarely encountered.

Spasmodic Dysphonia Types

There are four different types of spasmodic dysphonia:

• Adductor spasmodic dysphonia
  • Involuntary/sudden muscle movements/spasms
  • Vocal cords close and become rigid
  • Production of voice is affected
  • One cannot begin to speak or the speech is cut off all of a sudden
  • Strained/strangled voice
  • It takes a lot of effort for the person to speak
  • Spasms absent during certain activities (laughing, singing)
  • Aggravated by stress
• Abductor spasmodic dysphonia
  • Involuntary/sudden muscle movements/spasms
  • Vocal cords open
  • Air escape from the lungs during speech
  • Weak and quiet voice (resembling a whisper)
  • Spasms absent during certain activities (laughing, singing)
• Mixed spasmodic dysphonia
  • Involuntary/sudden muscle movements/spasms
  • Affects both the muscles that open and close the vocal cords
  • Borrows symptoms from both types (adductor and abductor)
• Whispering dysphonia
  • Caused by a genetic mutation
  • Recently discovered

Spasmodic Dysphonia Symptoms

These are the most common symptoms of spasmodic dysphonia:

• Difficult speaking
  • Gradual or sudden onset
• Voice can break up
• Certain speech sounds can come out modified
• The voice can sound breathy, with pauses being made because of the involuntary contractions of the muscles
• The voice can present a tremble or a shake, as the words are pronounced with difficulty
• Speaking is possible with a lot more physical effort, the person feels like he/she is out of breath after speech
• The voice becomes similar to the one during a cold or a laryngitis episode
• The voice can sound strained or strangled
• Sometimes it resembles more of a whisper or it is interrupted by breathy pauses
• Speech sounds are often interrupted by the involuntary contractions, as these cause the voice to be modified
• If the spasm is more severe, then it can interrupt the voice completely
• Symptoms are often aggravated by stress or anxiety
• The voice can also be accompanied by a specific tremor
• The voice is absent in more severe cases.

What are the Causes of Spasmodic Dysphonia?

Until the present moment, an exact cause of spasmodic dysphonia has yet to be identified. According to the latest research, it seems that the main problem is related to the basal ganglia. These are found at the base of the brain and they are responsible for the regulation of muscle movements that are involuntary. If the regulatory function is not alright, then the ganglia will send the wrong signals to the rest of the body. The signals will automatically translate into badly timed contractions of the muscles, such as the ones encountered in spasmodic dysphonia.

Researchers have had an even more difficult time in identifying the case, as the involuntary muscle movements do not occur with all types of speech. According to the research made by specialists in the field, it seems that the symptoms of spasmodic dysphonia diminish or disappear completely when a person laughs, cries, yells, tries to clear his/her throat, whisper or hum. The condition is related to specific tasks and it seems that it might have something to do with abnormal reflexes of the brainstem. Genetics have also been considered as a cause of this condition, the genetic inheritance of spasmodic dysphonia being a definite possibility.

Scientists consider the following to be triggering factors but not causes of spasmodic dysphonia: infections with different viruses, trauma or injury to the head, respiratory conditions (bronchitis), surgery (post-operative complication) and stress or anxiety (these often aggravate the symptoms of the condition). The cause is not as important as making the correct diagnosis, so as the best treatment can be administered to the patient suffering from spasmodic dysphonia.

Diagnosis

The correct diagnosis of spasmodic dysphonia is hard to make, as there are no obvious modifications at the level of the larynx. One cannot use regular imagining investigations or common blood tests to obtain the diagnosis. Moreover, this condition is quite similar with other disorders of the vocal cords, which makes the diagnosis even more difficult. Other conditions, such as muscle tension dysphonia, excessive straining of the voice, neurological modifications of the voice and the weak Parkinson’s voice are often mistaken for spasmodic dysphonia. It is said that it takes a very good doctor to be able to make this diagnosis.

These are the most common steps taken for the diagnosis of spasmodic dysphonia:

• Obtaining the medical history of the patient
• Assessment of speech sounds (identification of voice breakups)
• Asking the patient to read specific sentences (the sentences include specific sounds)
• Physical examination of the larynx
  • If physical modifications, such as nodules or inflammation of the larynx, are identified then the diagnosis is not spasmodic dysphonia
  • Physical examination of the larynx is possible with an endoscope (rigid or flexible) and a stroboscope (light source)
• Laryngeal electro-myography
  • Offers useful information about the laryngeal muscles
  • The electrical activity of the muscles during speech and rest is recorded

Treatment

From the start, it should be mentioned that there are no treatments available that are capable of curing this condition. The administered treatments often address the symptoms, keeping the muscle spasms under control or bringing temporary relief. The person suffering from spasmodic dysphonia can benefit from treatment, as it will allow for control over one’s voice. In many situations, the treatment is administered with the purpose of increasing the quality of the voice.

There are three major approaches to spasmodic dysphonia, meaning through speech therapy, medication and surgery. Each approach has its own set of benefits and it will be chosen according to each patient. The oral medication is administered but it rarely brings relief from the symptoms experienced. Among the most commonly recommended medication, there are anticholinergic drugs, benzodiazepines and baclofen. Botulin toxin has been administered as a nerve blocker with successful results. Surgery is considered for patients who are diagnosed with adductor spasmodic dysphonia. The surgical procedures include thyroplasty, denervation and selective laryngeal adductor denervation-rennervation. Speech therapy is highly helpful, as it helps the patient learn what can be done to improve quality of voice and what should be avoided.