Spasmodic dysphonia is a chronic (long-term) neurological speech disorder. It changes the way your voice performs and sounds when you speak. The condition may also be called spastic vocal cords or spastic dysphonia.
In some people with spasmodic dysphonia, voice changes every few sentences or as often as every word. In severe cases, the condition can make a person difficult to understand.
Spasmodic dysphonia can start at any age, but it usually begins in middle to late age (40s, 50s or 60s). For unknown reasons, it affects women more than men.
The condition is rare, affecting only about 1 person per 100,000.
Scientists aren’t sure what causes spasmodic dysphonia. But they believe it’s neurological (related to a problem in an area of the brain, specifically the basal ganglia). Researchers are exploring neurological causes, as well as a possible genetic link.
Physicians and scientists do understand how spasmodic dysphonia happens. If you have the condition, the muscles in the larynx (voice box) can spasm either open or closed when you try to talk. The sudden, involuntary spasms can make the vocal cords (folds) move in abnormal ways, which affects your voice. The spasms that cause the vocal changes may come and go for no clear reason. There's been an association with stress and increased spasms.
However, the larynx often behaves normally during other activities, such as:
The condition can happen in a few different ways:
Most cases of spasmodic dysphonia start gradually. Once symptoms begin, they may worsen for about 18 months and then stay about the same.
People with spasmodic dysphonia have described their voices as:
Spasmodic dysphonia is difficult to diagnose because the larynx looks normal, so tests like MRI and CT scan don't show anything. Plus, the symptoms can be similar to other disorders.
Diagnosis may require a healthcare team, including:
An otolaryngologist may perform a test called a videostroboscopy to look at your larynx and listen to your voice. The specialist inserts a small, lit tube through your nose and into the back of your throat. It shows the larynx and the vocal cords, as well as how they move during speech and other activities.
The specialists will listen to your voice. They may use imaging tests such as MRI to look for any problems in the brain but this isn't commonly done.
There's no cure for spasmodic dysphonia. But some treatments may ease the symptoms or make the condition less severe, such as:
Spasmodic dysphonia can't be prevented. There are no known risk factors or lifestyle changes that can lessen your chances of developing it.
Spasmodic dysphonia is a chronic, lifelong condition. Even with successful treatments, the symptoms will come back.
Researchers are working to learn more about spasmodic dysphonia. They're exploring its possible causes, as well as better ways to diagnose and treat it.
People with spasmodic dysphonia have several options to cope with the effects of the condition, such as:
A note from Cleveland Clinic
Spasmodic dysphonia is a speech disorder that changes the way your voice performs and sounds. If you're having trouble with your voice, talk to a healthcare provider. A team of specialists can diagnose the condition and offer various treatments and ways to cope.