Vocal fold paresis: evidence and controversies

Abstract

To present and assess the current state of knowledge regarding vocal fold paresis. Neurogenic compromise of vocal fold function exists along a continuum encompassing partial denervation (paresis), complete denervation (paralysis), and variable degrees and patterns of reinnervation. Not abundantly recognized clinically until recently, paresis typically presents with symptoms of glottic insufficiency. As a result of preserved vocal fold mobility, paresis can be difficult to diagnose and to distinguish from innocent vocal fold asymmetry. Laryngoscopy alone has proved an unreliable means of diagnosis, and laryngeal electromyography, although not immune to error itself, is often helpful. Treatment consists of medialization procedures that do not compromise remaining nerve function. Significant disagreement exists regarding the incidence, causes and relationship to other pathologies. In the absence of evidence, natural history must be inferred. Vocal fold paresis is probably a significant source of vocal disability, especially among cases that have eluded straightforward diagnosis. An accurate assessment of its clinical impact, patterns of dysfunction, natural history and relationship to other pathologies depends on diagnostic rigor and accuracy and is still evolving.