Sensory Function in Idiopathic Voice Disorders
Condition: Phonation Disorder; Spastic Dysphonia; Voice Disorder
MeSH terms: Dysphonia; Hoarseness; Voice Disorders
Study type: Observational

Summary: 
      This research study is designed to improve understanding about voice disorders that are due
      to uncontrolled muscle contractions affecting the voice box. The type of voice disorder
      depends on which muscles of the voice box are involved. Abductor spasmodic dysphonia may lead
      to a weak voice. Adductor spasmodic dysphonia may result in a strangled voice. Muscular
      tension dysphonia may lead to a strained voice. Some of the major goals of the study are to;

        1. understand how sensation from the voice box affects voice and speech production

        2. develop better ways to diagnose sensation abnormalities affecting the voice box

        3. determine if patients with voice disorders differ from persons without voice disorders
           in the way they respond to sensory information from their voice box

      Researchers believe that by understanding better how sensations of the voice box are
      presented and how the muscles in the larynx respond to those sensations they will be able to
      develop better treatments for patients suffering from voice disorders. ...
    

Detailed description: 
      Study Aim One: To develop and validate objective procedures for quantifying efferent
      responses to non-invasive laryngeal mechanical and aerodynamic stimulation.

      Study Aim Two: To develop and validate an objective test of brain stem evoked responses to
      laryngeal stimulation using electrical stimulation of the superior laryngeal nerve.

      Study Aim Three: To determine whether individuals with idiopathic voice disorders have
      abnormal conditioning of their responses to laryngeal mechanical and aerodynamic stimulation.

      Study Aim Four: To determine whether individuals with idiopathic voice disorders have
      abnormal brain stem responses to laryngeal stimuli.

      Study Aim Five: To evaluate whether sensory input plays a role in symptom generation in
      laryngeal motor control disorders, temporary bilateral ISLN blockade will be used in
      idiopathic voice disorders.

      Study Aim Six: To evaluate whether the central pathophysiology involved in motor responses to
      sensory stimulation are altered by botulinum toxin injection in individuals with spasmodic
      dysphonia.

      Study Aim Seven: To evaluate central responses to laryngeal afferent stimulation in normal
      volunteers and patients with idiopathic voice disorders at rest and during vocalization using
      magnetoencephalography.

      These studies will develop improved non-invasive techniques for the diagnosis of laryngeal
      sensory disorders and will determine if abnormalities in sensory feedback modulation are
      involved in idiopathic voice disorders. Such findings will lead to improved understanding of
      the pathophysiology and differential diagnosis of idiopathic voice disorders and may
      ultimately improve treatment approaches to these disorders.
    

Keywords: Evoked Response; Spasmodic Dysphonia; Aerodynamic; Vibration; Laryngeal; Voice Disorders; Laryngeal Brainstem Evoked Responses; Long-latency Responses; Muscular Tension Dysphonia