Stage Whisper Variant of Adductory Spasmodic Dysphonia (AD-SD)

The common phenomenology of adductory spasmodic dysphonia (AD-SD) includes both strain and phonatory arrests. Strain produces a gravelly, “squeezed and strangled” voice quality, while phonatory arrests cause the voice to “catch” or “grab,” resulting in syllable or word dropouts.

A frequently overlooked variant is tonic variant adductor SD—often misdiagnosed as “muscle tension dysphonia.” Rather than intermittent spasms, this form involves sustained tonic contraction, manifesting as constant strain, with few or no phonatory arrests. The analogy is the “squint” variant of ocular dystonia (blepharospasm), compared with the more typical exaggerated blinking pattern.

Within this tonic category lies a sub-variant we call the “stage-whisper” tonic adductory SD. Because of its whisper-like quality, it may be misinterpreted as abductor SD. However, the defining feature is the squeezed, strained, “stage-whisper” voice, confirming an adductory rather than abductory spasm pattern.