Prevalence of abnormal laryngeal findings in healthy singing teachers

Abstract

Objective: To determine the prevalence of abnormal laryngeal findings during strobovideolaryngoscopy and objective voice measurement in healthy singers without significant voice complaints.

Study design: Prospective evaluation of professional singing teachers.

Setting: A quiet room in a hotel during a convention of the National Association of Teachers of Singing.

Subjects: Seventy-two volunteers (60 females and 12 males), all of whom were trained singers without significant voice complaints.

Main outcome measure: Abnormalities observed on strobovideolaryngoscopy.

Secondary outcome measure: Abnormalities identified during acoustic analysis.

Results: Abnormalities were found during strobovideolaryngoscopy in 86.1% (62 of 72 of subjects, many of whom had more than one abnormality. For the purpose of this study, the authors defined "normal" as having no structural pathology (masses, cysts, ectasias, and so on) and a reflux finding score (RFS) of less than 7. Subjects' evaluations were considered "abnormal" if they had at least one documented laryngeal pathology and/or an RFS≥7. The most common findings were signs associated with laryngopharyngeal reflux (LPR). Subjects were also identified with prominent varicosities or ectasias, incomplete glottic closure, and structural abnormalities. LPR was observed in 72% of patients using the physical findings (arytenoid erythema and/or edema) relied on typically to establish the clinical diagnosis as well as using the RFS (16.7% in women and 25% in men). Posterior laryngeal mucosal hypertrophy was also demonstrated in 64% of the participants. Acoustic analysis of female subjects showed that shimmer, relative average perturbation, and maximum fundamental frequency differed significantly from widely used norms.

Conclusion: Laryngeal abnormalities occur commonly in asymptomatic patients. Physicians must exercise caution in establishing a causal relationship between an observed abnormality and a patient's voice complaint. Baseline examinations of voice patients when they are healthy and asymptomatic should be encouraged to establish each individual's "normal" condition.