Spasmodic dysphonia, a form of the neurologic condition known as dystonia, results from involuntary spasms of the larynx, producing interruptions of speech and changes in voice quality. The pathogenesis of spasmodic dysphonia is not well understood. However, several genetic mutations have been identified that cause different forms of dystonia. In some individuals, these genetic mutations result...

This study describes preliminary laryngeal electromyography (LEMG) data and botulinum toxin treatment in patients with dysphonia due to movement disorders. Twenty-five patients who had been clinically selected for botulinum toxin administration were examined, 19 with suspected laryngeal dystonia or spasmodic dysphonia (SD), 5 with vocal tremor, and 1 with Gilles de la Tourette syndrome (GTS). L...

Adductor spasmodic dysphonia is the most common form of laryngeal dystonia and comprises about 80% of all laryngeal dystonias. It is characterized by strained and strangled voice quality causing significant impairment to the patient. This article focuses on the surgical treatment of adductor spasmodic dysphonia by thyroarytenoid muscle ablation. It provides longlasting control of symptoms and p...

Dear Editor, Dystonia is a movement disorder characterised by sustained muscle contractions, repetitive twisting movements, and abnormal postures of the trunk, neck, face, or arms and legs.1 Classifi cation of this condition may be based on topography, age at onset, cause, or by the presence of genetic markers.1 When unaccompanied by other neurologic abnormalities, and in the absence of known c...

Adductory spasmodic dysphonia is a focal dystonia of laryngeal muscles. Patients with this disorder typically have severe vocal difficulties, with significant functional, social, and emotional consequences. There is no widely accepted cure for this condition, however, botulinum toxin injections of the thyroarytenoid muscles are considered by most voice clinicians to be the state of the art trea...

Description and quantification of the symptoms of adductor spasmodic dysphonia often reflect the clinician's knowledge of the disorder, ideas about the cause of the disorder, and personal experience. No reliable instrument that identifies and quantifies the spectrum of perceptual symptoms has been available. Therefore, we developed a standardized measure called the Unified Spasmodic Dysphonia R...

Botulinum neurotoxin (BoNT) has existed for thousands of years; however, it was not medically utilized until investigations into its therapeutic use began in sincerity during the late 1970s and 1980s. This, coupled with the reclassification of spasmodic dysphonia as a focal dystonia, led to the use of chemodenervation for this disorder, which has since become a refined technique. Indeed, due to...

BACKGROUND Dystonia is a movement disorder characterized by involuntary muscle contractions that cause twisting movements and abnormal postures. Primary dystonia is the most common form and is thought to be a multifactorial condition in which one or more genes combine with environmental factors to reach disease. METHODS We reviewed controlled studies on possible environmental risk factors for...