Skip to main content
Professional Technical IVT

spasmodic dysphonia

Also written as: SD — Spasmodic Dysphonia

Neurological voice disorder characterized by involuntary vocal fold spasms causing voice breaks, strain, or breathiness.

Full Definition

Spasmodic dysphonia (SD) is a focal dystonia affecting the laryngeal muscles, resulting in involuntary spasms that disrupt normal voice production. The two primary types are adductor SD, characterized by voice breaks and strained quality due to excessive vocal fold closure, and abductor SD, featuring breathy voice breaks from inappropriate vocal fold opening. This neurological condition typically requires botulinum toxin injections for management, as traditional voice therapy alone is generally ineffective for treating the underlying dystonic symptoms.

Usage

Usage note: Specify adductor or abductor type when known; commonly abbreviated as SD in clinical notes.

In Context

  • "The patient's adductor spasmodic dysphonia was successfully managed with bilateral botulinum toxin injections." — Medical treatment report
  • "Differential diagnosis considered spasmodic dysphonia versus muscle tension dysphonia based on voice quality patterns." — Diagnostic evaluation

Also known as

SD laryngeal dystonia

Don't confuse with

muscle tension dysphonia vocal tremor

Editors from these organisations have used our services since 1998

Reuters BBC Oxford University Press Penguin Random House Springer Microsoft Suncor Energy United Nations Fisher Investments IBM The Home Depot KODAK CHEVRON