Contribution of Glottic Insufficiency to Perceived Breathiness in Classically Trained Singers.

Breathiness in the singing voice is problematic for classical singers. Voice students and singing teachers typically attribute breathiness to breath management issues and breathing technique. The present study sought to determine whether glottic insufficiency may also contribute to breathiness in a singer's voice. Studies have revealed a relationship between insufficient vocal fold closure and inefficiency in the speaking voice. However, the effect of insufficient vocal fold closure on vocal efficiency in singers has yet to be determined. Two groups of voice students identified with and without breathiness issues underwent aerodynamic and acoustic voice assessment as well as laryngeal stroboscopy of the vocal folds to quantify the prevalence of insufficient vocal fold closure, also known as glottic insufficiency. These assessments revealed four groups: 1) those with glottic insufficiency and no perceived voice breathiness; 2) those with glottic sufficiency and perceived voice breathiness; 3) those with glottic insufficiency and perceived breathiness; and 4) those with glottic sufficiency and no perceived breathiness. Results suggest that previously undiscovered glottal insufficiency is common in young singers, particularly women, though the correlation with identified breathiness was not statistically significant. Acoustic and aerodynamic measures including noise-to-harmonics ratio, maximum phonation time, airflow rate, subglottal pressure, and laryngeal airway resistance were most sensitive to glottic insufficiency.

Validation of the Yale Swallow Protocol: a prospective double-blinded videofluoroscopic study.

The purpose of this prospective, double-blinded, multirater, systematic replication study was to investigate agreement for aspiration risk, in the same individual, between videofluoroscopic swallow studies (VFSS) and the Yale Swallow Protocol. Participants were 25 consecutive adults referred for dysphagia testing who met the inclusion criteria of completion of a brief cognitive assessment, oral mechanism examination, and no tracheotomy tube. First, all participants were administered the Yale Swallow Protocol by two experienced speech-language pathologists trained in protocol administration. Failure criteria were inability to drink the entire amount, interrupted drinking, or coughing during or immediately after drinking. Second, all participants completed a VFSS within 5-10 min of protocol administration. A speech-language pathologist, blinded to protocol results, reviewed the VFSS to determine aspiration status in a binary (yes/no) manner. Inter-rater agreement between two speech-language pathologists was 100 % for identification of aspiration risk with the Yale Swallow Protocol. Inter-rater agreement between the speech-language pathologist and the radiologist for identification of aspiration status with VFSS was 100 %. Twenty percent of VFSS recordings were viewed again 3-6 months after initial data collection, and intrarater agreement for identification of thin liquid aspiration was 100 %. Sensitivity for the Yale Swallow Protocol = 100 %, specificity = 64 %, positive predictive value = 78 %, and negative predictive value = 100 %. Importantly, all participants who passed the protocol did not aspirate during VFSS. Multiple, double-blinded raters and VFSS as the reference standard agreed with previous research with a single, nonblinded rater and FEES as the reference standard for identification of aspiration risk. The clinical usefulness and validity of the Yale Swallow Protocol for determining aspiration risk in a small sample size of male participants has been confirmed. Future research is needed with a larger and more heterogeneous population sample.