Voice Therapy in Muscle Tension Dysphonia

By Adamantia Prachali, SLP, MSc, Supervisor Speech Language Pathology, Inpatient Therapies & Rehabilitation, Cleveland Clinic Abu Dhabi

Voice is one of the most important tools of the human body and it can be as unique as our fingerprint. It helps define our personality, mood, and health and when affected can contribute to significant changes in quality of life.

Approximately 17.9 million adults in the U.S. have trouble using their voices. Disorders of the voice involve problems with pitch, loudness, and quality. Pitch is the highness or lowness of a sound based on the frequency of the sound waves. Loudness is the perceived volume of the sound, while quality refers to the character or distinctive attributes of a sound.

Many people who have normal speaking skills have great difficulty communicating when their voice has been affected. This can occur if the nerves controlling the larynx are impaired because of an accident, a surgical procedure, a viral infection, or cancer.

However, in many cases the change in the voice might not be related to any of the above and the patient might suffer from hoarseness or throat discomfort that is caused simply by the “wrong use of the muscles”. The term used to describe this condition is Muscle Tension Dysphonia (MTD). Other terms often used to describe the same condition include: ‘Vocal Hyperfunction’, ‘Hyperfunctional Voice Disorder’ and ‘Muscle Tension Imbalance’.

Effective, comfortable singing and speech relies on maintaining a comfortable balance of tension in the muscles of voicing. These include the muscles that control vocal fold closure, pitch change and resonance balance in the upper airway above the larynx. If these muscles become overly tight, they may tire more easily, so that other less effective muscles are then recruited to ‘help out’. Over time the voice starts to produce symptoms and may become hoarse, constricted, unreliable and uncomfortable.

In most cases, MTD produces vocal symptoms without any actual physical damage. However, in the long term, MTD can sometimes cause vocal fold swelling and irritation so it is best to treat it early.

What are the symptoms of Muscle Tension Dysphonia?

  • Tiredness, aching or pain that develops in the larynx or throat when speaking or singing
  • Dryness or scratchiness in the larynx with voice use
  • A change in voice quality, particularly during long periods of voice use or at the end of the day
  • A change in the vocal pitch (too high, too low, unstable or pitch breaks)  
  • Changes in voice quality are often variable and can include some or all of the following symptoms:
  • Roughness, hoarseness or a raspy quality
  • A tight, strained, tense or ‘squeezed’ quality
  • A breathy, weak quality
  • Voice ‘breaks’

How is Muscle Tension Dysphonia diagnosed?
MTD can only be diagnosed through examination of the larynx. Ideally an ear, nose and throat doctor (ENT Surgeon/Laryngologist) and a speech and language pathologist (SLP) working together in a voice clinic would investigate the causes of the voice problem through observation of the larynx during voice production, a careful history, and analysis of how the voice sounds. The symptoms associated with MTD can be caused by other conditions, so it is important that these are excluded before starting any voice therapy.

What causes Muscle Tension Dysphonia?
There are usually a number of factors involved in the development of MTD. It may arise from:

  • Long-term patterns of ineffective voice use
  • Changes in voice production associated with a period of vocal overuse, an infection or emotional stress
  • Compensation for an underlying vocal fold problem such as a cyst, paresis or fatigue in the vocal muscles
  • A ‘guarding’ response to stress, acid reflux or some other irritant
  • A combination of some or all of the above factors.  

How is Muscle Tension Dysphonia treated?
Depending on the diagnosis, MTD without any other vocal fold abnormality is usually treated by a SLP specialising in voice disorders. Treatment may require only a few sessions or may take several months depending on how long the patient has had the problem and his or her individual response to treatment. The goal of voice therapy is to decrease excessive or inappropriately placed tension so that the vocal muscles can function effectively again.

If MTD is the primary cause of damage to the vocal fold or, alternatively, has developed to compensate for an underlying vocal or health problem, the ENT surgeon will explain and discuss the medical/surgical treatment options open to the patient. If surgery is required, attending voice therapy during recovery to resolve any persisting symptoms of MTD that might undermine recovery is recommended.

What does Voice Therapy involve?
Voice therapy is a programme designed to reduce hoarseness through guided change in vocal behaviors and lifestyle changes. Voice therapy consists of a variety of tasks designed to eliminate harmful vocal behavior and shape healthy vocal behaviour. Voice therapy for hoarseness generally consists of one to two therapy sessions each week for 4–8 weeks. The duration of therapy is determined by the origin of the hoarseness and severity of the problem, co-occurring medical therapy, and, importantly, patient commitment to the practice and generalisation of new vocal behaviours outside the therapy session.

Are speech therapy and voice therapy the same?
Speech therapy is a term that encompasses a variety of therapies including voice therapy. Most referring providers as well as insurance companies refer to voice therapy as speech therapy, but they are the same if provided by a certified and licensed speech-language pathologist.

References available on request.
Prachali discussed ‘SLP management of Vocal Fold Paralysis’ on April 26 at the ME OTO Exhibition 2019.