Spasmodic dysphonia

Spasmodic dysphonia, or laryngeal dystonia, is a neurologic disorder that affects voice and speech. It’s a lifelong condition that causes the muscles that generate a person’s voice to go into periods of spasm. The condition most commonly begins in middle age, affecting people assigned female at birth more often than people assigned male at birth. Because its symptoms can closely match those of another voice disorder called muscle tension dysphonia, an accurate diagnosis is an important first step.

At Penn Medicine, specialists with expertise in voice disorders work together to diagnose spasmodic dysphonia and other causes of voice changes. Our team includes laryngologists, neurologists, and experts in speech and language pathology, who evaluate how the vocal cords function during speech. If another neurological condition is involved, we coordinate care with neurology specialists and provide therapies that help reduce vocal strain and improve how your voice works.

People with spasmodic dysphonia may experience:

• Breaks or interruptions in speech, often every few sentences
• A hoarse, grating voice that can also sound strained, strangled, or breathy
• Odd sounding speech that's difficult to understand
• Gradual or sudden difficulty speaking
• Symptoms that may go away when you laugh, whisper, sing, or shout
• Muscle tone problems in other parts of the body, like writer's cramp

The exact cause of spasmodic dysphonia is unknown. However, most cases result from a problem in the brain and nervous system that affects how the voice muscles work. Stress may make symptoms worse.

For muscle tension dysphonia, a different voice disorder, there’s usually a specific event that leads it to develop. These events may include:

• Surgery
• A virus
• Inflammatory illness
• Lesions
• Neurologic conditions such as multiple sclerosis or Parkinson's disease

Dysphonia can be hard to diagnose because the larynx often looks normal. We use your medical history and assess your speech to listen for voice breaks.

A diagnostic tool called video stroboscopy may be used to rule out other conditions like nodules, polyps, or cancer. Video stroboscopy is a painless, outpatient procedure that uses a synchronized, flashing light to see your vocal cord vibrations. During this exam, a flexible tube equipped with a strobe light and camera is passed through your nose. In some cases, a rigid telescope is gently placed through the mouth and over the tongue to view the vocal cords. A microphone placed on the neck helps detect the frequency of vocal cord vibration during speech.