A Comparison of the Effects of Phonation into a Positive Expiratory Pressure Device and Silicone Tube in Water on the Vocal Mechanism.

OBJECTIVES: Positive expiratory pressure (PEP) devices have become an additional therapeutic approach for treating voice disorders. Similar to water resistance therapy (WRT), phonation in a PEP device introduces a secondary source of vibration within the vocal tract. This investigation aimed to compare the effects of phonation using a PEP device and silicone tube phonation (STP) commonly used in WRT on the vocal mechanism during phonation. METHODS: Three normophonic subjects participated in the study. High-speed videoendoscopy, pressure, airflow, electroglottography, and acoustic recordings were collected. RESULTS: The results demonstrated that phonation using both the PEP device and silicone tube induced alterations in glottal behavior. The PEP device produced more pronounced and consistent pressure oscillations, impacting the glottal cycle and influencing parameters including contact quotient (CQ), fundamental frequency, glottal area, pressure, and airflow. The regular vibratory mechanism of the PEP device systematically modified the glottal cycle. In STP, regular bubbling at lower depths of submersion produced higher CQ values, supporting the efficacy of deep bubbling exercises for inducing glottal adduction. CONCLUSIONS: The findings suggest that phonation using PEP devices has a more pronounced impact on the vocal tract and glottis. It also provides a stronger massage effect that directly affects the glottal source. Phonation with a silicone tube produces similar results, although to a lesser extent and with lower regularity. These findings offer guidance in the selection of voice therapy devices.

A Pilot Study Assessing the Therapeutic Potential of a Vibratory Positive Expiratory Pressure Device (Acapella Choice) in the Treatment of Voice Disorders.

INTRODUCTION: Semioccluded vocal tract exercises (SOVTEs) can involve a single source of vibration (eg, vocal folds in the straw exercise) or a dual source of vibration (eg, vocal folds and water bubbling in tube phonation) in the vocal tract. Oftentimes, this secondary source of vibration causes large oscillations in intraoral pressure and has been likened to a "massage effect." This study assesses the implementation of a positive expiratory pressure device (Acapella Choice) as a possible alternative SOVTE, which presents a secondary source of vibration without the need of a water container. METHODS: Twenty-two normophonic participants underwent acoustic, electroglottographic, and aerodynamic assessment before, during, and after phonation with two different established SOTVEs (silicone tube in water and straw in air) in addition to Acapella Choice. RESULTS: Acapella Choice produced the largest peak-to-peak amplitudes of intraoral pressure oscillation. Straw in air produced the largest static intraoral pressure. Straw in air and Acapella Choice presented significantly larger ranges of static pressures than tube in water phonation. Post-exercise condition showed a statistically larger sound pressure level for Acapella Choice. CONCLUSIONS: Positive expiratory pressure devices, such as Acapella Choice, may be a promising alternative to established SOVTEs as it promotes large oscillatory pressures in the vocal tract without the need for a water container. This exercise also produces larger sound pressure level with no significant changes in glottic contact quotient, indicating improved vocal economy.

Observational study of differences in head position for high notes in famous classical and non-classical male singers.

INTRODUCTION: Differences in classical and non-classical singing are due primarily to aesthetic style requirements. The head position can affect the sound quality. This study aimed at comparing the head position for famous classical and non-classical male singers performing high notes. METHOD: Images of 39 Western classical and 34 non-classical male singers during live performances were obtained from YouTube. Ten raters evaluated the frontal rotational head position (depression versus elevation) and transverse head position (retraction versus protraction) visually using a visual analogue scale. RESULTS: The results showed a significant difference for frontal rotational head position. DISCUSSION AND CONCLUSION: Most non-classical singers in the sample elevated their heads for high notes while the classical singers were observed to keep it around the neutral position. This difference may be attributed to different singing techniques and phonatory system adjustments utilized by each group.

The Flow and Pressure Relationships in Different Tubes Commonly Used for Semi-occluded Vocal Tract Exercises.

This experimental study investigated the back pressure (P(back)) versus flow (U) relationship for 10 different tubes commonly used for semi-occluded vocal tract exercises, that is, eight straws of different lengths and diameters, a resonance tube, and a silicone tube similar to a Lax Vox tube. All tubes were assessed with the free end in air. The resonance tube and silicone tube were further assessed with the free end under water at the depths from 1 to 7 cm in steps of 1 cm. The results showed that relative changes in the diameter of straws affect P(back) considerably more compared with the same amount of relative change in length. Additionally, once tubes are submerged into water, P(back) needs to overcome the pressure generated by the water depth before flow can start. Under this condition, only a small increase in P(back) was observed as the flow was increased. Therefore, the wider tubes submerged into water produced an almost constant P(back) determined by the water depth, whereas the thinner straws in air produced relatively large changes to P(back) as flow was changed. These differences may be taken advantage of when customizing exercises for different users and diagnoses and optimizing the therapy outcome.