Configuration of vocal folds during and after tube phonation in patients with voice disorders: A computerized tomographic study

Extrinsic Laryngeal Muscle Activity With Different Diameters and Water Depths in a Semi-Occluded Vocal Tract Exercise

PURPOSE

Surface electromyography (sEMG) has been used to evaluate extrinsic laryngeal muscle activity during swallowing and phonation. In the current study, sEMG amplitudes were measured from the infrahyoid and suprahyoid muscles during phonation through a tube submerged in water.

METHOD

The sEMG amplitude values measured from the extrinsic laryngeal muscles and the electroglottographic contact quotient (CQ) were obtained simultaneously from 62 healthy participants (31 men, 31 women) during phonation through a tube at six different depths (2, 4, 7, 10, 15, and 20 cm) while using two tubes with different diameters (1 and 0.5 cm).

RESULTS

With increasing depth, the sEMG amplitude for the suprahyoid muscles increased in men and women. However, sEMG amplitudes for the infrahyoid muscles increased significantly only in men. Tube diameter had a significant effect on the suprahyoid sEMG amplitudes only for men, with higher sEMG amplitudes when phonating with a 1.0-cm tube. CQ values increased with submerged depth for both men and women. Tube diameter affected results such than CQ values were higher for men when using the wider tube and for women with the narrower tube.

CONCLUSIONS

Vocal fold vibratory patterns changed with the depth of tube submersion in water for both men and women, but the patterns of muscle activation differed between the sexes. This suggests that men and women use different strategies when confronted with increased intraoral pressure during semi-occluded vocal tract exercises. In this study, sEMG provided insight into the mechanism for differences between vocally normal individuals and could help detect compensatory muscle activation during tube phonation in water for people with voice disorders.

Optimizing Diameter, Length, and Water Immersion in Flow Resistant Tube Vocalization

OBJECTIVE

The objective was to quantify the range of airflow resistance and oral pressure attainable with variation of length, diameter, and water immersion depth of tubes and straws.

STUDY DESIGN

Pressure-flow equations for tubes, determined previously for variable tube geometries, were used to calculate oral pressure ranges. Human subjects were then recruited to use the variable tube geometries to produce oral pressures, which were quantified with commercial manometers.

RESULTS

Nomograms for airflow resistances and oral pressures are plotted as a function of tube length, tube diameter, and water insertion depth.

CONCLUSIONS

It is shown that tube diameters in the range of 2.5-3.0 mm with tube lengths of 10-40 cm produce oral pressures in the range of 10-40 cm H2O. Insertion of the distal end into water adds a pressure in the amount of the depth of insertion. Maximum power transfer with different tube geometries is discussed.

Pressure, Flow, and Glottal Area Waveform Profile Changes During Phonation Using the Acapella Choice Device

INTRODUCTION

Vibratory positive expiratory pressure (PEP) devices are now commonly used as a resource for voice therapy. PEP devices promote improved vocal economy with the added benefit of producing a massage effect in the vocal tract. Although the benefits of PEP devices for voice have already been demonstrated, their impact on the vocal source is still not very clear. This study assesses the impact of phonation into the Acapella Choice (a type of PEP device) on the voice.

METHODS

Three normophonic subjects underwent high-speed videoendoscopy assessment while pressure, flow and electroglottographic data was collected.

RESULTS

Phonation into the Acapella device produces large changes in the pressure and flow profiles consequently affecting the voice source. In specific, when intraoral pressure increases as a consequence of the downward movement of the rocker arm in the Acapella device (reduction of the airflow outlet), phonation is hindered, demonstrated by the lower amplitude of vibration of the vocal folds and weaker modulation of the pressure and flow values by the glottal cycle. When the rocker arm in the Acapella device opens (increasing the airflow outlet), the opposite trend is observed where vocal fold vibration is aided and the modulation of pressure and flow by the vocal cycle increases. Based on the pressure and flow signals, we can assume that the impedance of the vocal tract alternates between two dominant regimes: increased inertive reactance (aided vibration) and increased resistance (hindered vibration).

CONCLUSIONS

PEP devices, such as the Acapella device, are efficient in modulating the pressure and flow profiles in the vocal tract leading to the alternation of glottal vibration from aided to hindered. These changes in the glottal vibration can be considered an additional consequence of the massage effect caused by the Acapella device.

Effectiveness of a physiologic voice therapy program based on different semioccluded vocal tract exercises in subjects with behavioral dysphonia: A randomized controlled trial

PURPOSE

The present study aimed to assess the effectiveness of a physiologic voice therapy program based on different semioccluded vocal tract exercises in subjects with behavioral dysphonia.

METHODS

Thirty-four participants with behavioral dysphonia were randomly assigned to one of two treatment groups: 1) voice treatment with physiologic voice therapy plus vocal hygiene program (n=20), and 2) vocal hygiene program only (n=14). Laryngoscopic assessment was performed in all subjects. Before and after voice therapy, participants underwent aerodynamic, electroglottographic, and acoustic assessment. The Voice Handicap Index (VHI), Voice symptom scale (VoiSs), Vocal tract discomfort scale (VTDS), and self-assessment of resonant voice quality were also performed. The treatment included eight voice therapy sessions. For the experimental group, the exercises consisted of a sequence of seven phonatory tasks performed with four different semioccluded vocal tract exercises (SOVTE). Comparison for all variables were performed between experimental group and control group.

RESULTS

Wilcoxon test showed significant improvements for experimental group for VHI, VoiSs, VTDS (decrease), and self-perception of resonant voice quality (increase). Significant decrease for experimental groups was observed on subglottic pressure, phonation threshold pressure, and glottal airflow across the implemented tasks.

CONCLUSION

Physiologic voice therapy based on semioccluded vocal tract exercises seems to be an effective tool to improve voice in subjects diagnosed with behavioral dysphonia. Apparently, most changes should be expected in variables related to physical and functional aspects compared to objective variables. Subglottic pressure and phonation threshold pressure seem to be the most change-sensitive parameters and they may reflect a reduction in phonatory effort reported by patients after voice therapy.

Voiced High-Frequency Oscillation or Lax Vox Technique? Immediate Effects in Dysphonic Individuals

OBJECTIVES

To analyze the immediate effects of voiced high-frequency oscillation (VHFO) and Lax Vox technique on vocal quality and self-reported intensity of vocal and laryngeal symptoms in individuals with behavioral dysphonia.

METHODS

This experimental, prospective, randomized cross-over study, investigated thirty adults (15 women and 15 men) with behavioral dysphonia (vocal complaints, altered voice on auditory-perceptual evaluation, vocal nodules or mucosal thickening, and incomplete glottic closure). The outcome variables analyzed were auditory-perceptual analysis, acoustic analysis (voice quality characteristics), and self-reported intensities of vocal and laryngeal symptoms. Each participant performed two exercises-VHFO and Lax Vox technique-in a random sequence for 3 minutes. A 7-day washout period was provided between the exercises. The data were analyzed using the paired t-test and Wilcoxon test (P < 0.05).

RESULTS

After VHFO, no significant difference was observed on auditory-perceptual evaluation in all participants, whereas the Lax Vox technique worsened breathiness among women (P = 0.027). VHFO significantly increased the fundamental frequency (P = 0.014) and decreased the noise harmonic ratios for women (P = 0.026). Among men, there was a decrease in shimmer parameter (P = 0.035). Moreover, symptoms such as "lump in the throat" (P = 0.005), "voice loss" (P = 0.017), and "high-pitched voice" (P = 0.023) decreased in women after VHFO, whereas in men, "itchiness" and "hoarseness" (P < 0.001) decreased after VHFO. The Lax Vox technique decreased "hoarseness" (P = 0.003) in women, without any effect in men.

CONCLUSION

The VHFO exercise provided more positive immediate effects results than the Lax Vox technique regarding vocal quality and self-reported symptom intensity in participants with behavioral dysphonia.

Variation on Vocal Economy After Different Semioccluded Vocal Tract Exercises in Subjects With Normal Voice and Dysphonia

PURPOSE

The present study aimed at observing the possible differential effects of eight semioccluded vocal tract exercises (SOVTE) on vocal economy measured by the Quasi Output Cost Ratio (QOCR).

METHODS

Thirty-six participants were included in this study. They were divided into two groups: an experimental group of subjects diagnosed with mild hyperfunctional dysphonia (n = 17) and a control group of vocally healthy subjects (n = 19). Participants were required to randomly select and produce a series of three SOVTE from a list of eight exercises. The electroglottographic based measure QOCR was used to calculate the vocal economy before and after each voice exercise.

RESULTS

Significant differences were found when comparing pre and poststages regardless of the vocal condition (normal voice or dysphonia) or the specific SOVTE used. Moreover, when individually comparing the effect of each SOVTE, only tube in water (10 cm) showed significant differences between pre and postconditions (QOCR values were higher after exercises).

CONCLUSION

In general, semioccluded vocal tract exercises tend to increase vocal economy regardless the vocal condition (normal voice or dysphonia) or the specific SOVTE used. Phonation into a tube submerged deep into water promoted the highest increase in vocal economy. An increased acoustic output, nonproportional increase in vocal folds adduction and an effortless voice production would cause this increase in vocal economy after water resistance therapy.