Strategies for Minimizing the Effects of Observer Variability on Sagittal Parameter Measurements of the Spine.

STUDY DESIGN: Exploratory-descriptive study. OBJECTIVE: Evaluate the influence of observer variability on the measurements of both thoracic kyphosis (TK) and lumbar lordosis (LL) obtained with anatomic and functional spinal segmentation methods. BACKGROUND: Parametric analysis for spinal surgery planning typically relies on anatomic parameters. However, incorporating functional parameters that consider the vertebrae orientation is important to minimizing surgical calculation errors. METHODS: The authors developed parametric analysis software that integrates traditional and functional methodologies. The proposed method included functional thoracic kyphosis and functional lumbar lordosis calculated from the lines normal to the inflection points of the spine model. Using a synthetic lateral X-ray, the observer variability was computer-simulated generating 20 landmark sets that replicate the annotations of 20 observers. The analysis also included 10 clinical X-rays, annotated twice by 3 judges with a minimum 1-week interval. The spinal curvature angles were derived using the anatomic and functional methods. Statistical analysis were performed for comparison. RESULTS: For the synthetic X-ray, the proposed method presented significantly less variability: TK (<±2.5 degrees, P=0.00023) and LL (<±5 degrees, P=0.00012). For the clinical X-rays, the interobserver reliability analysis yielded higher intraclass correlation coefficients (ICC) for functional TK (ICC>0.97) and functional LL (ICC>0.87) than for TK (ICC<0.91) and LL (ICC<0.89). Statistically significant differences were observed for both TK (P=0.001) and LL (P=0.030). Under the traditional method, observer variability led to measurement differences surpassing ±19 degrees, whereas differences with the proposed method were within ±10 degrees for both parameters. CONCLUSION: The vertebral endplate is not the most suitable place to measure spinal sagittal curvatures. Small changes in landmark position significantly alter the measured Cobb angle. The proposed method offers a substantial advantage regarding the influence of observer variability, in addition to the more individualized analysis.

Excised human larynx in N-vinyl-2-pyrrolidone-embalmed cadavers can produce voiced sound by pliable vocal fold vibration.

Tissue-hardening effect and health-hazard issue of formaldehyde (FA) have long been a great disadvantage of this conventional fixative in anatomical research. We recently developed a FA-free embalming method for cadavers which utilizes N-vinyl-2-pyrrolidone (NVP) and enables assessment of motion kinetics by maintaining the softness of embalmed tissue. By assessing the feasibility of NVP-embalmed tissue to mimic vocalization, this study aimed to prove the potential of embalmed cadavers, which have previously been used only for the understanding of anatomical morphology, for the assessment of precise motion physiology in the human body. Ten cadavers embalmed in NVP (n = 6) and FA (n = 4) were incorporated in this study. Excised larynges underwent experimental phonation to mimic vocalization with fast and pliable vibration of vocal folds. High-speed digital imaging was utilized for the assessment of vocal fold vibration. Furthermore, acoustic analysis of the voiced sound, and reproducibility examination were also performed. Regular vocal fold vibrations successfully produced voiced sounds during experimental phonation using NVP-embalmed larynges. The vibratory frequency, vibration amplitude, and stretch rate of the vocal folds were comparable to those of living humans. Six months after the first experiment, the vocal parameters were reproduced, to suggest the long-term preservation potential of our NVP-embalming technique. On the other hand, neither voiced sound nor vocal fold vibration were observed in FA-embalmed larynges. This novel embalming technique could pioneer the next era to utilize embalmed cadavers for the examination of motion physiology in the human body.

Source and Filter Acoustic Measures of Young, Middle-Aged and Elderly Adults for Application in Vowel Synthesis.

INTRODUCTION: The output sound has important changes throughout life due to anatomical and physiological modifications in the larynx and vocal tract. Understanding the young adult to the elderly speech acoustic characteristics may assist in the synthesis of representative voices of men and women of different age groups. OBJECTIVE: To obtain the fundamental frequency (f0), formant frequencies (F1, F2, F3, F4), and bandwidth (B1, B2, B3, B4) values extracted from the sustained vowel /a/ of young, middle-aged, and elderly adults who are Brazilian Portuguese speakers; to present the application of these parameters in vowel synthesis. STUDY DESIGN: Prospective study. METHODS: The acoustic analysis of tokens of the 162 sustained vowel /a/ produced by vocally healthy adults, men, and women, between 18 and 80 years old, was performed. The adults were divided into three groups: young adults (18 to 44 years old); middle-aged adults (45 to 59 years old) and, elderly adults (60 to 80 years old). The f0, F1, F2, F3, F4, B1, B2, B3, B4 were extracted from the audio signals. Their average values were applied to a source-filter mathematical model to perform vowel synthesis in each age group both men and woman. RESULTS: Young women had higher f0 than middle-aged and elderly women. Elderly women had lower F1 than middle-aged women. Young women had higher F2 than elderly women. For the men's output sound, the source-filter acoustic measures were statistically equivalent among the age groups. Average values of the f0, F1, F2, F3, F4, B1, and B2 were higher in women. The sound waves distance in signals, the position of formant frequencies and the dimension of the bandwidths visible in spectra of the synthesized sounds represent the average values extracted from the volunteers' emissions for the sustained vowel /a/ in Brazilian Portuguese. CONCLUSION: Sustained vowel /a/ produced by women presented different values of f0,F1 and F2 between age groups, which was not observed for men. In addition to the f0 and the formant frequencies, the bandwidths were also different between women and men. The synthetic vowels available represent the acoustic changes found for each sex as a function of age.

Fundamental Frequency in Excised Human Larynges after Anterior Glottic Web Formation of Various Extents.

OBJECTIVE: To determine the effect of vocal fold anterior web formation on fundamental frequency with a cadaveric excised larynx model. STUDY DESIGN: Experimental study with excised human larynges. SETTING: Academic tertiary care hospital. SUBJECTS AND METHODS: Sixteen freshly excised human larynges were evaluated with high-speed videoendoscopy and digital kymography during artificially produced vibration. Each larynx was assessed in 4 conditions: preoperative controls and after 25%, 33%, and 50% decreases in the vibratory portion of the vocal folds. The following parameters were evaluated: fundamental frequency, periodicity, vocal fold vibration amplitude, phase symmetry, and glottic closure. RESULTS: The mean fundamental frequencies were 208.87, 250.20, 292.37, and 342.67 Hz for preoperative controls and 25%, 33%, and 50% reductions in vibratory length of the vocal folds, respectively. Fundamental frequency increased with each increase in anterior glottic web extent, and the difference among the groups was statistically significant in absolute values in hertz and in semitone elevation. The mathematical models for estimating postoperative fundamental frequency had a statistically significant coefficient. The vibration of the vocal folds remained periodic in all larynges before and after the procedures. CONCLUSION: There was a significant and progressive increase in the fundamental frequency with each enlargement of anterior glottic web. Based on the control frequency, mathematical models could estimate the value of the fundamental frequency after the procedure.

Global Kalman filter approaches to estimate absolute angles of lower limb segments.

BACKGROUND: In this paper we propose the use of global Kalman filters (KFs) to estimate absolute angles of lower limb segments. Standard approaches adopt KFs to improve the performance of inertial sensors based on individual link configurations. In consequence, for a multi-body system like a lower limb exoskeleton, the inertial measurements of one link (e.g., the shank) are not taken into account in other link angle estimations (e.g., foot). Global KF approaches, on the other hand, correlate the collective contribution of all signals from lower limb segments observed in the state-space model through the filtering process. We present a novel global KF (matricial global KF) relying only on inertial sensor data, and validate both this KF and a previously presented global KF (Markov Jump Linear Systems, MJLS-based KF), which fuses data from inertial sensors and encoders from an exoskeleton. We furthermore compare both methods to the commonly used local KF. RESULTS: The results indicate that the global KFs performed significantly better than the local KF, with an average root mean square error (RMSE) of respectively 0.942° for the MJLS-based KF, 1.167° for the matrical global KF, and 1.202° for the local KFs. Including the data from the exoskeleton encoders also resulted in a significant increase in performance. CONCLUSION: The results indicate that the current practice of using KFs based on local models is suboptimal. Both the presented KF based on inertial sensor data, as well our previously presented global approach fusing inertial sensor data with data from exoskeleton encoders, were superior to local KFs. We therefore recommend to use global KFs for gait analysis and exoskeleton control.

Impact of Cricothyroid Muscle Contraction on Vocal Fold Vibration: Experimental Study with High-Speed Videoendoscopy.

OBJECTIVES: The aim of this study was to evaluate the effects of cricothyroid muscle contraction on vocal fold vibration, as evaluated with high-speed videoendoscopy, and to identify one or more aspects of vocal fold vibration that could be used as an irrefutable indicator of unilateral cricothyroid muscle paralysis. STUDY DESIGN: This was an experimental study employing excised human larynges. METHODS: Twenty freshly excised human larynges were evaluated during artificially produced vibration. Each larynx was assessed in three situations: bilateral cricothyroid muscle contraction, unilateral cricothyroid muscle contraction, and no contraction of either cricothyroid muscle. The following parameters were evaluated by high-speed videoendoscopy: fundamental frequency, periodicity, amplitude of vocal fold vibration, and phase symmetry between the vocal folds. RESULTS: Although neither unilateral nor bilateral cricothyroid muscle contraction altered the periodicity of vibration or the occurrence of phase asymmetry, there was a significant decrease in fundamental frequency in parallel with decreasing longitudinal tension. We also found an increase in vibration amplitude of right and left vocal folds, which were similar in terms of their behavior for this parameter in the various situations studied. CONCLUSION: Our results suggest that differences in vibration amplitude and phase symmetry between vocal folds are not reliable indicators of unilateral cricothyroid muscle paralysis.

High-speed Videolaryngoscopy: Quantitative Parameters of Glottal Area Waveforms and High-speed Kymography in Healthy Individuals.

OBJECTIVES: We conducted a study to obtain quantitative parameters of the vocal dynamic using high-speed videolaryngoscopy and to characterize the vocal fold vibration pattern of healthy individuals by analyzing glottal area waveforms and high-speed kymography. METHODS: Laryngeal images of 45 healthy individuals were captured using high-speed videolaryngoscopy. The open and speed quotients of the glottal area waveforms and high-speed kymography were obtained and statistically analyzed according to the gender of each individual. RESULTS: Glottal area waveforms revealed average values of 0.85 and 1.16 for open and speed quotients, respectively, for women, and 0.70 and 1.19 for men. Using high-speed kymography, quantitative parameters of open and speed quotients for women were 0.62 and 1.02, respectively, and for men were 0.57 and 1.12. By gender, a significant statistical difference emerged for open quotients obtained from both glottal area waveforms (P = 0.004) and high-speed kymography (P = 0.013). CONCLUSION: Obtained by using computational tools specifically for analyzing laryngeal images from high-speed videolaryngoscopy, quantitative parameters of glottal area waveforms and high-speed kymography in healthy individuals provide reference data and normality for future studies.

Perturbation Measurements on the Degree of Naturalness of Synthesized Vowels.

OBJECTIVE: To determine the impact of jitter and shimmer on the degree of naturalness perception of synthesized vowels produced by acoustical simulation with glottal pulses (GP) and with solid model of the vocal tract (SMVT). STUDY DESIGN: Prospective study. METHODS: Synthesized vowels were produced in three steps: 1. Eighty GP were developed (20 with jitter, 20 with shimmer, 20 with jitter+shimmer, 20 without perturbation); 2. A SMVT was produced based on magnetic resonance imaging (MRI) from a woman during phonation-/ε/ and using rapid prototyping technology; 3. Acoustic simulations were performed to obtain eighty synthesized vowels-/ε /. Two experiments were performed. First Experiment: three judges rated 120 vowels (20 humans+80 synthesized+20% repetition) as "human" or "synthesized". Second Experiment: twenty PowerPoint slide sequences were created. Each slide had 4 synthesized vowels produced with the four perturbation condition. Evaluators were asked to rate the vowels from the most natural to the most artificial. RESULTS: First Experiment: all the human vowels were classified as human; 27 out of eighty synthesized vowels were rated as human, 15 of those were produced with jitter+shimmer, 10 with jitter, 2 without perturbation and none with shimmer. Second Experiment: Vowels produced with jitter+shimmer were considered as the most natural. Vowels with shimmer and without perturbation were considered as the most artificial. CONCLUSIONS: The association of jitter and shimmer increased the degree of naturalness of synthesized vowels. Acoustic simulations performed with GP and using SMVT demonstrated a possible method to test the effect of the perturbation measurements on synthesized voices.

Vocal Tract Adjustments of Dysphonic and Non-Dysphonic Women Pre- and Post-Flexible Resonance Tube in Water Exercise: A Quantitative MRI Study.

OBJECTIVE: To compare vocal tract (VT) adjustments of dysphonic and non-dysphonic women before and after flexible resonance tube in water exercise (FRTWE) at rest and during phonation using magnetic resonance imaging. STUDY DESIGN: Prospective study. METHODS: Twenty women, aged 20-40 years, 10 dysphonic with vocal nodules (VNG) and 10 controls (CG), underwent four sets of sagittal VT MRI: two pre-FRTWE, at rest and during phonation, and two post-FRTWE, during phonation and at rest. The subjects performed 3 minutes of exercise. Nine parameters at rest and 21 during phonation were performed. RESULTS: Pre-FRTWE, eight significant differences were found, three at rest and five during phonation: at rest - laryngeal vestibule area, distance from epiglottis to pharyngeal posterior wall (PPW) and interarytenoid complex length were smaller in the VNG; during phonation - laryngeal vestibule area, angle between PPW and vocal fold (VF), epiglottis to PPW, and anterior commissure of the larynx to laryngeal posterior wall were smaller in the VNG; tongue area was larger in the VNG. Post-FRTWE, only three significant differences were found, two during phonation and one at rest: during phonation - angle between PPW and VF and the membranous portion of the VF length were smaller in the VNG; at rest - distance from epiglottis to PPW was smaller in the VNG. CONCLUSIONS: Results suggest that the habitual VT adjustments of dysphonic and non-dysphonic women are different at rest and during phonation. The FRTWE promoted positive VT changes in the VNG, reducing the intergroup differences.

Auditory-perceptual evaluation of rough and breathy voices: correspondence between analogical visual and numerical scale. / Análise perceptivo-auditiva de vozes rugosas e soprosas: correspondência entre a escala visual analógica e a escala numérica.

PURPOSE: To determine the cut-off values of different degrees of vocal roughness and breathiness in an analogical visual scale, from a numerical scale. METHODS: We selected 150 voices from both genders, with quality ranging from neutrality to intense deviations, and predominance of breathiness or roughness. The auditory-perceptual assessment through two scales: 100-mm analogical visual scales and 4-point numerical scale. Intra and interrater reliability of auditory-perceptual ratings was analyzed using the Intraclass Correlation Coefficient. The cut-off values for graduation of roughness and breathiness voices were determinate using the analysis of the Receiver Operating Characteristic (ROC) curve, which is based on the sensitivity, specificity and efficiency. RESULTS: The intra and interrater reliability of auditory-perceptual ratings was excellent on both scales. The cut-off values (mm) in the analogical visual scale, from the numeric scale, indicated a roughness distribution: 0-8.5 absence of the parameter; 8.5- 28.5 mild presence; 28.5- 59.5 moderate and 59.5- 100 intense. For breathiness, the distribution was: 0-8.5 absence of the parameter; 8.5-33.5 for mild presence; 33.5-52.5 moderate and 52.5-100 intense. CONCLUSION: The cut-off values found for the analogical visual scale conclude that the numerical scale zero, which represents the absence of parameter, corresponds to a small range of scores in the analogical visual scale. Furthermore, the third degree of the numerical scale corresponded to a wide range of the analogical visual scale.

Análise perceptivo-auditiva de vozes rugosas e soprosas: correspondência entre a escala visual analógica e a escala numérica / Auditory-perceptual evaluation of rough and breathy voices: correspondence between analogical visual and numerical scale

RESUMO Objetivo: Determinar os valores de corte dos diferentes graus de rugosidade e soprosidade vocal em uma escala visual analógica, a partir de uma escala numérica. Métodos: Foram selecionadas 150 vozes, de indivíduos de ambos os gêneros, com qualidade variando desde a ausência de rugosidade e de soprosidade até a presença desses parâmetros em grau intenso. A avaliação perceptivo-auditiva foi realizada por quatro fonoaudiólogas especialistas em voz, com a utilização da escala visual analógica de 100 mm e da escala numérica de quatro pontos. A concordância intra e interjuízes foi verificada por meio do Coeficiente de Correlação Interclasse. Os valores de corte foram obtidos com base nos valores de sensibilidade, especificidade e eficiência. Resultados: A concordância intra e interjuízes foi excelente em ambas as escalas. Os valores de corte definiram as faixas de distribuição, encontrando-se para a rugosidade: grau 0 até 8,5 mm; grau 1 de 8,5 a 28,5 mm; grau 2 de 28,5 a 59,5 mm; e grau 3 a partir de 59,5 mm. Para a soprosidade encontrou-se: grau 0 até 8,5 mm; grau 1 de 8,5 a 33,5 mm; grau 2 de 33,5 a 52,5 mm; e grau 3 a partir de 52,5 mm. Conclusão: A partir dos valores de corte encontrados para a escala visual analógica foi possível concluir que o grau 0 (zero) da escala numérica, que representa a ausência do parâmetro, corresponde a uma pequena faixa de pontuação de presença do parâmetro na escala visual analógica. Além disso, o grau 3 da escala numérica correspondeu a uma extensa faixa da escala visual analógica.

ABSTRACT Purpose: To determine the cut-off values of different degrees of vocal roughness and breathiness in an analogical visual scale, from a numerical scale. Methods: We selected 150 voices from both genders, with quality ranging from neutrality to intense deviations, and predominance of breathiness or roughness. The auditory-perceptual assessment through two scales: 100-mm analogical visual scales and 4-point numerical scale. Intra and interrater reliability of auditory-perceptual ratings was analyzed using the Intraclass Correlation Coefficient. The cut-off values for graduation of roughness and breathiness voices were determinate using the analysis of the Receiver Operating Characteristic (ROC) curve, which is based on the sensitivity, specificity and efficiency. Results: The intra and interrater reliability of auditory-perceptual ratings was excellent on both scales. The cut-off values (mm) in the analogical visual scale, from the numeric scale, indicated a roughness distribution: 0-8.5 absence of the parameter; 8.5- 28.5 mild presence; 28.5- 59.5 moderate and 59.5- 100 intense. For breathiness, the distribution was: 0-8.5 absence of the parameter; 8.5-33.5 for mild presence; 33.5-52.5 moderate and 52.5-100 intense. Conclusion: The cut-off values found for the analogical visual scale conclude that the numerical scale zero, which represents the absence of parameter, corresponds to a small range of scores in the analogical visual scale. Furthermore, the third degree of the numerical scale corresponded to a wide range of the analogical visual scale.

Improvement of Vocal Pathologies Diagnosis Using High-Speed Videolaryngoscopy

Introduction The study of the dynamic properties of vocal fold vibration is important for understanding the vocal production mechanism and the impact of organic and functional changes. The advent of high-speed videolaryngoscopy (HSV) has provided the possibility of seeing the real cycle of vocal fold vibration in detail through high sampling rate of successive frames and adequate spatial resolution. Objective To describe the technique, advantages, and limitations of using HSV and digital videokymography in the diagnosis of vocal pathologies. Methods We used HSV and digital videokymography to evaluate one normophonic individual and four patients with vocal fold pathologies (nodules, unilateral paralysis of the left vocal fold, intracordal cyst, and adductor spasmodic dysphonia). The vocal fold vibration parameters (glottic closure, vibrational symmetry, periodicity, mucosal wave, amplitude, and glottal cycle phases) were assessed. Results Differences in the vocal vibration parameters were observed and correlated with the pathophysiology. Conclusion HSV is the latest diagnostic tool in visual examination of vocal behavior and has considerable potential to refine our knowledge regarding the vocal fold vibration and voice production, as well as regarding the impact of pathologic conditions have on the mechanism of phonation...

Comparative analysis of vocal fold vibration using high-speed videoendoscopy and digital kymography.

OBJECTIVES: To compare high-speed videoendoscopy (HSV) and digital kymography (DKG) in the vocal fold vibration analysis of normophonic women with no vocal fold abnormalities. STUDY DESIGN: Prospective study comparing quantitative parameters extracted by HSV and DKG. METHODS: Eighteen normophonic women whose age ranged from 18 to 45 years participated in the study. The procedures comprised HSV and DKG of the medial line of the vocal folds. The parameters evaluated were fundamental frequency (F0), open quotient (OQ), and duration of vibration cycle phases (open phase, closed phase, opening phase, and closing phase). RESULTS: The F0 results of HSV and DKG were similar. However, significant differences were found in both duration of vibration cycle phases and OQ, indicating a longer open phase in the vocal fold vibration when this phase was measured by HSV. CONCLUSIONS: The results emphasize the need to set up different normative threshold values for both HSV and DKG.

Graphical evaluation of vocal fold vibratory patterns by high-speed videolaryngoscopy.

OBJECTIVE: To characterize the voice and vocal fold function of an individual, it is essential to evaluate vocal fold vibration. The most widely used method for this purpose has been videolaryngoscopy. METHODS: This article proposes a digital image processing algorithm to estimate the glottal area (ie, the space between the vocal folds) and produce graphs of the opening and closing phases of the glottal cycle. In eight subjects without voice disorders, vocal fold movements were recorded by high-speed videolaryngoscopy at 4000 frames per second. The video data were processed by a combination of image segmentation techniques that estimate the glottal area. The segmented area was used to construct the glottal waveform. RESULTS: The graphs revealed important properties of vocal fold vibration, including amplitude, velocity, and other characteristics that have a major influence on voice quality. CONCLUSIONS: The combination of the high-speed technology with the proposed method improves the vocal fold analysis given a numerical feedback through graphical representation of the real vibratory patterns of the folds.

Improvement of vocal pathologies diagnosis using high-speed videolaryngoscopy.

Introduction The study of the dynamic properties of vocal fold vibration is important for understanding the vocal production mechanism and the impact of organic and functional changes. The advent of high-speed videolaryngoscopy (HSV) has provided the possibility of seeing the real cycle of vocal fold vibration in detail through high sampling rate of successive frames and adequate spatial resolution. Objective To describe the technique, advantages, and limitations of using HSV and digital videokymography in the diagnosis of vocal pathologies. Methods We used HSV and digital videokymography to evaluate one normophonic individual and four patients with vocal fold pathologies (nodules, unilateral paralysis of the left vocal fold, intracordal cyst, and adductor spasmodic dysphonia). The vocal fold vibration parameters (glottic closure, vibrational symmetry, periodicity, mucosal wave, amplitude, and glottal cycle phases) were assessed. Results Differences in the vocal vibration parameters were observed and correlated with the pathophysiology. Conclusion HSV is the latest diagnostic tool in visual examination of vocal behavior and has considerable potential to refine our knowledge regarding the vocal fold vibration and voice production, as well as regarding the impact of pathologic conditions have on the mechanism of phonation.

Parameters Acoustic and High-speed kymography identified effects of voiced vibration and vocal fry exercises / Parametros acusticos e quimografia de alta velocidade identificam efeitos imediatos dos exercicios de vibracao sonorizada e som basal

Purpose: To identify the immediate effects of voiced vibration and vocal fry exercises on healthy subjects by means of acoustic parameters and high-speed kymography. Methods: Thirty healthy subjects (18 women and 12 men, aged from 19 to 45 years old) participated in this study. The voices were recorded at the range of 44.100 samples/second, before and after of the vocal exercises. We developed a computational routine to extract jitter and shimmer. High-speed kymography was generated from laryngeal images for the analysis of the phase times: closed (CPh), open (OPh), of closing (cPh) and of opening (oPh) and used the paired t-Student test and the Mann-Whitney test, with a significance level of 0.05. Results: After voiced vibrations, acoustic parameters showed reduced jitter for both genders (p=0.018 for men and p<0.01 for women) and reduced shimmer for female voices (p<0.01). There was a decrease in CPh (p=0.046) and cPh (p=0.026) and an increase in OPh (p=0.05) in female vocal folds. After vocal fry, we identified decreased jitter (p<0.01) in female voices and cPh (p=0.026) in male vocal folds. Conclusion: We observed more positive immediate effects of the voiced vibrations, mainly in voice quality and vocal folds among females. Nevertheless, studies with larger male sample and investigation of the appropriate time of vocal fry are necessary to confirm the results of this search. .

OBJETIVO: Identificar efeitos imediatos das vibrações sonorizadas e do som basal em indivíduos saudáveis por meio de parâmetros acústicos e quimografia de alta velocidade. MÉTODOS: Participaram 30 sujeitos, 12 homens e 18 mulheres (19 a 45 anos) sem alterações laríngeas. As vozes foram gravadas à taxa de 44.100 amostras/segundo e as videolaringoscopias de 4.000 quadros/segundo, antes e depois dos exercícios vocais. Foi desenvolvida uma rotina computacional para extrair Jitter e Shimmer. Foram geradas quimografias de alta velocidade a partir das imagens laríngeas para a análise dos tempos de fase: fechada (FF); aberta (FA); de fechamento (Ff) e de abertura (Fa), e usados o Teste t de Student pareado e o teste Mann-Whitney, com nível de significância de 0,05. RESULTADOS: Após as vibrações sonorizadas, houve diminuição de Jitter (0,018 para homens e p<0,01para mulheres) para ambos os gêneros e diminuição de Shimmer (p<0,01) ao gênero feminino. Houve diminuição de FF (p=0,046) e de Ff (p=0,026) e aumento de FA (p=0,05) em pregas vocais femininas. Após o som basal, foram identificados diminuição de Jitter (p<0,01) em vozes femininas e da Ff (p=0,026) em pregas vocais masculinas. CONCLUSÃO: Foi possível verificar mais efeitos imediatos positivos após as vibrações sonorizadas principalmente em qualidade vocal e pregas vocais de mulheres. No entanto, são necessárias pesquisas com maior número de amostras masculinas e investigação sobre o tempo adequado do som basal para corroboração dos resultados desta pesquisa. .

High-speed kymography identifies the immediate effects of voiced vibration in healthy vocal folds

Introduction: The effects of voiced vibration technique can be assessed by laryngeal imaging. Kymographic images derived from high-speed videoendoscopy allow actual visualization of vocal folds vibration. Purpose: The aim of this study is to identify the immediate effects of the voiced vibration technique in healthy vocal folds using high-speed digital laryngeal imaging. Methods: Samples were obtained from 15 healthy subjects with no history of voice disorders (6 men and 9 women aged 21 to 43 years). High-speed videoendoscopy recordings were performed before and after the voiced vibration technique. Kymographic images were obtained using high-speed videoendoscopy. The vocal folds were examined in their open and closed positions and the characteristics of the opening and closing phases were determined. A customize computational routine was used quantify these parameters. The closing, opening, and speed quotients were also calculated. Results: In this study, women displayed statistically significant differences in opened phase (P= 0.05*), closed phase (P= 0.046*), and closing phase (P= 0.026*) phase characteristics. Men displayed the highest difference rate in opening time characteristics (P= 0.06). The closing and opening quotients for the female group showed significant differences (P= 0.029* and P= 0.049*, respectively). The speed quotient exhibited statistically significant differences in the male group (P= 0.048*). Conclusion: The kymographic images indicated that the immediate effect of the voiced vibration technique was smooth contact in healthy vocal fold vibration...

Parameters acoustic and high-speed kymography identified effects of voiced vibration and vocal fry exercises.

PURPOSE: To identify the immediate effects of voiced vibration and vocal fry exercises on healthy subjects by means of acoustic parameters and high-speed kymography. METHODS: Thirty healthy subjects (18 women and 12 men, aged from 19 to 45 years old) participated in this study. The voices were recorded at the range of 44.100 samples/second, before and after of the vocal exercises. We developed a computational routine to extract jitter and shimmer. High-speed kymography was generated from laryngeal images for the analysis of the phase times: closed (CPh), open (OPh), of closing (cPh) and of opening (oPh) and used the paired t-Student test and the Mann-Whitney test, with a significance level of 0.05. RESULTS: After voiced vibrations, acoustic parameters showed reduced jitter for both genders (p=0.018 for men and p<0.01 for women) and reduced shimmer for female voices (p<0.01). There was a decrease in CPh (p=0.046) and cPh (p=0.026) and an increase in OPh (p=0.05) in female vocal folds. After vocal fry, we identified decreased jitter (p<0.01) in female voices and cPh (p=0.026) in male vocal folds. CONCLUSION: We observed more positive immediate effects of the voiced vibrations, mainly in voice quality and vocal folds among females. Nevertheless, studies with larger male sample and investigation of the appropriate time of vocal fry are necessary to confirm the results of this search.

High-speed kymography identifies the immediate effects of voiced vibration in healthy vocal folds.

INTRODUCTION: The effects of voiced vibration technique can be assessed by laryngeal imaging. Kymographic images derived from high-speed videoendoscopy allow actual visualization of vocal folds vibration. PURPOSE: The aim of this study is to identify the immediate effects of the voiced vibration technique in healthy vocal folds using high-speed digital laryngeal imaging. METHODS: Samples were obtained from 15 healthy subjects with no history of voice disorders (6 men and 9 women aged 21 to 43 years). High-speed videoendoscopy recordings were performed before and after the voiced vibration technique. Kymographic images were obtained using high-speed videoendoscopy. The vocal folds were examined in their open and closed positions and the characteristics of the opening and closing phases were determined. A customize computational routine was used quantify these parameters. The closing, opening, and speed quotients were also calculated. RESULTS: In this study, women displayed statistically significant differences in opened phase (P = 0.05*), closed phase (P = 0.046*), and closing phase (P = 0.026*) phase characteristics. Men displayed the highest difference rate in opening time characteristics (P = 0.06). The closing and opening quotients for the female group showed significant differences (P = 0.029* and P = 0.049*, respectively). The speed quotient exhibited statistically significant differences in the male group (P = 0.048*). CONCLUSION: The kymographic images indicated that the immediate effect of the voiced vibration technique was smooth contact in healthy vocal fold vibration.

Comparative analysis of the closed quotient for lip and tongue trills in relation to the sustained vowel /ε/.

Various types of trill exercises have been used for a long time as a tool in the treatment and preparation of the voice. Although they are reported to produce vocal benefits in most subjects, their physiology has not yet been studied in depth. The aim of this study was to compare the mean and standard deviation of the closed quotient in exercises of lip and tongue trills with the sustained vowel /ε/ in opera singers. Ten professional classical (operatic) singers, reportedly in perfect laryngeal health, served as subjects for this study and underwent electroglottography. During the examination, the subjects were instructed to deliver the sustained vowel /ε/ and lip and tongue trills in a same preestablished frequency and intensity. The mean values and standard deviation of the closed quotient were obtained using the software developed for this purpose. The comparison of the results was intrasubjects; maximum intensities were compared only among them and so were minimum intensities. The means of closed quotient were statistically significant only in the strong intensities, and the lip trill was different from the tongue trill and the sustained vowel /ε/. The standard deviation of the closed quotient distinguished the sustained vowel /ε/ from the lip and tongue trills in the two intensities. We concluded that there is oscillation of the closed quotient during the exercises of tongue and lip trills, and the closed quotient is higher during the performance of exercises of the lip trill, when compared with the two other utterances, only in the strong intensities.