NORMAL STROBOVIDEOLARYNGOSCOPY - VARIABILITY IN HEALTHY SINGERS

Strobovideolaryngoscopy has proven essential to accurate diagnosis of voice disorders. Clinical interpretation of stroboscopic images usuall y follows a standard assessment protocol. Features analyzed typically include symmetry of amplitude, symmetry of phase, regularity of period icity, amplitudes and wave forms of individual vocal folds, presence o r absence of adynamic segments, and other features. Speed and smoothne ss of abduction and adduction are also assessed. In order for strobosc opic data to be used meaningfully in a clinical setting, it is essenti al for the laryngologist to recognize the range of normal variability of these parameters. This may be particularly important when trying to establish diagnoses for subtle voice disorders in professional voice users. This study investigates strobovideoiaryngoscopic findings in a population of normal professional singers without voice complaints. '' Abnormal'' strobovideolaryngoscopic findings occur in this asymptomati c population of ''volunteers.'' These abnormalities might have been mi sinterpreted as causing voice complaints if seen for the first time wh en the singer sought medical care for a voice problem. Physicians must be aware of the range of laryngeal behavior that may be found among n ormal subjects and must be cautious when interpreting strobovideolaryn goscopic findings. This study also highlights the importance of obtain ing ''normal'' baseline strobovideolaryngoscopic evaluations on profes sional voice users. The review of strobovideolaryngoscopy performed up on 65 healthy, asymptomatic professional singers revealed an incidence of 58% ''abnormal'' findings as six clinical entities.