Health A-Z

Symptoms and Types of Spasmodic Dysphonia

For reasons that are unknown to physicians, speech-language pathologist and researchers, in patients with SD, the brain sends abnormal signals to the muscle of the voice box (larynx) to causes the muscles to spasm. These spams cause the voice to break or crack or choke off. In the majority of patients (90 percent), the signals lead to spasms that cause the muscle of the vocal folds to close too tightly (adductor spasms or AddSD). In these patients the voice has a harsh or strangled quality. This often sounds like the person is about to cry. In about 10 percent of patients, the signals lead to spasms that cause the muscles of the vocal folds to open (abductor spasms or AbdSD). The voice sounds intermittently breathy or the patient whispers. Finally a small percentage of patients have a mix of both types of spasms (Mixed SD). The voice is has a combination of strain/strangle breaks and breathy breaks.

The voice breaks in patients’ with SD happen when people with the disease attempt to say certain sounds. The spams causing the voice breaks are limited to the muscles of the voice box. This is referred to as task specific spasms. For AddSD the task causing spasm is saying vowels sound. When the person attempts to say a word with a vowel, the muscles of the vocal folds spasm shut. For AbdSD the task is saying a consonant. During consonants production the vocal folds are apart or abducted. The vocal fold muscle to spasm open, all the air rushes out and the voice is breathy. These limited spasms that are triggered by a task (saying a vowel or saying a consonant) are the definition of a focal dystonia. SD is a “focal dystonia” because the area of the body affected is limited to one system (the voice box) and the spasm are triggered by the task of speaking.

Regardless of the type of SD, persons with the disorder complain of increased effort to speak. If they try to speak loudly the effort is worse. Persons with the disorder are also troubled because the spams are uncontrollable and they often spend effort searching for words that are less likely to trigger the stress. Imagine not only having to think about what you say but the words you choose to say it with. Patients with SD usually notice that their effort is less if they speak softly or whisper. Also, if they speak in a high pitched voice, the effort can be less as well. Finally people with SD judge the severity of their difficulty in what they feel. Their voice often feels worse than it may sound to others and others may, therefore, downplay the severity of their feelings.

Treatment Options for Spasmodic Dysphonia

Several methods of treatment are available to patients with SD. At the Grabscheid Voice and Swallowing Center of Mount Sinai, our team of clinicians has experience with all of these modalities of treatment. We have piloted groundbreaking research in the use of novel medications to reduce the symptoms of laryngeal movement disorders. We use our experience to work with the patient to design treatment options that fit their needs. However, is should be stated that none of these treatments cure the disease; rather the treatments help the patient live with the disease. Treatment options include:

• Speech and Voice Therapy
  
  By working with a clinician experienced in the behaviors needed to produce healthy voice, the person with SD may learn how to adapt to the spasms with less interruption in their speech. This can allow the patient to function with less effort. In addition, it may help the patient by decreasing the need for other treatments such as medications, Botox® injections or surgery. Patients can be taught to use great airflow, or a softer voice to lessen the spasm severity.

Diagnosis of Spasmodic Dysphonia

SD is a diagnosis of exclusion. There are no medical tests that can definitively diagnose patients with SD so all other illness need to be ruled out first. The diagnosis is made on the basis of finding no other medical problems that could cause the relatively typical changes in voice that are found with the disorder.
The diagnosis is made by a clinician who is experienced in listening to voices and can have the patient do tasks that may make the symptoms worse or better. If the person has the voice characteristics and all other possible causes are ruled out, then by exclusion, they have SD.