Inspiratory and Expiratory Flow Changes, Voice Symptoms and Laryngeal Findings during Histamine Challenge Tests.

OBJECTIVE: The aim of this study was to analyse the associations between the spirometry parameter changes in relation to laryngeal finding changes and self-reported voice and throat symptom changes among patients undergoing a histamine challenge test. PATIENTS AND METHODS: Thirty adult patients with a chronic cough underwent a histamine challenge test. Videolaryngostroboscopy and voice and throat symptoms were assessed using a visual analogue scale immediately before and after the challenge test. Correlations between the relative changes in spirometry values in relation to the change in vocal fold oedema and redness and self-reported voice and throat symptom changes during the challenge test were assessed. RESULTS: A correlation between the relative change in inspiratory and expiratory air flow values and the change in voice and throat symptoms during the histamine challenge test was found. The vocal fold oedema, visible on videolaryngostroboscopy, caused by the histamine challenge did not significantly affect the spirometry air flow values. CONCLUSION: The relative changes in inspiratory and expiratory air flow and voice and throat symptoms during the histamine challenge test correlated. The vocal fold oedema caused by the histamine challenge, visible on videolaryngostroboscopy, did not significantly affect the spirometry air flow values.

Skewing of the glottal flow with respect to the glottal area measured in natural production of vowels.

In the production of voiced speech, glottal flow skewing refers to the tilting of the glottal flow pulses to the right, often characterized as a delay of the peak, compared to the glottal area. In the past four decades, several studies have addressed this phenomenon using modeling of voice production with analog circuits and computer simulations. However, previous studies measuring flow skewing in natural production of speech are sparse and they contain little quantitative data about the degree of skewing between flow and area. In the current study, flow skewing was measured from the natural production of 40 vowel utterances produced by 10 speakers. Glottal flow was measured from speech using glottal inverse filtering and glottal area was captured with high-speed videoendoscopy. The estimated glottal flow and area waveforms were parameterized with four robust parameters that measure pulse skewness quantitatively. Statistical tests obtained for all four parameters showed that the flow pulse was significantly more skewed to the right than the area pulse. Hence, this study corroborates the existence of flow skewing using measurements from natural speech production. In addition, the study yields quantitative data about pulse skewness in simultaneous measured glottal flow and area in natural production of speech.

Laryngeal Mucosal Reaction during Bronchial Histamine Challenge Test Visualized by Videolaryngostroboscopy.

OBJECTIVES/HYPOTHESIS: To examine the changes in the larynx, as well as self-reported voice and throat symptoms, among patients undergoing a histamine challenge test. Thus, to understand the possible clinical effects of histamine on the larynx. STUDY DESIGN: Controlled, open prospective study. METHODS: Thirty adult patients with prolonged cough and suspicion of bronchial asthma underwent a histamine challenge test. Videolaryngostroboscopy was performed immediately before and after the challenge. Voice and throat symptoms immediately before and after the challenge test were assessed using a visual analog scale. RESULTS: Videolaryngostroboscopy after exposure showed significant increases in edema (P < 0.001) as well as redness (P < 0.001) of the vocal folds after the exposure. Self-reported voice complaints increased significantly for 8 of 11 symptoms. A moderate positive correlation was found between the increase in edema of the vocal folds and reported heartburn/regurgitation symptoms (r = 0.42, P < 0.05). Atopy, asthma, nasal symptoms, or bronchial hyperreactivity during the histamine challenge test were not associated with laryngeal reactions. CONCLUSIONS: According to the results, the laryngeal mucosal reaction during a histamine challenge test can be objectively visualized. Videolaryngostroboscopy findings, together with an increase in self-reported voice and throat symptoms, show that histamine has potential effects on vocal folds. The mucosal reaction seems to be pronounced among patients with reflux symptoms, probably reflecting the permeability features of the vocal folds.

Detecting inaudible vocal organ changes through glottal inverse filtering.

The aim of this study was to investigate if there were objective quantities extracted from the speech pressure waveforms that underlay inaudible changes in the symptoms of the vocal organ. This was done through analyzing 180 voice samples obtained from nine subjects (five females and four males) before and after exposure to a placebo substance (lactose) and an organic dust substance. Acoustical analysis of the voice samples was achieved by using glottal inverse filtering. Results showed that the values of primary open quotient and primary speed quotient changed significantly (P<0.05) as did the amplitude quotient (P<0.01). Exposure to lactose resulted in significant changes of secondary open quotient (P<0.05) but opposite to effects found for exposure to organic dust. Modeling of the vocal tract into cross-sectional planes revealed that the immediate plane above the vocal folds correlates inversely with the feeling that voice is tense, or feeling the need to make an effort when speaking in addition having a feeling of shortness of breath or the need to gasp for air. Such results may point to acoustically detected subclinical changes in the vocal organ that the subject him/herself feels while they remain perceptually undetected by others.

[Exercise laryngoscopy: a new method for the differential diagnosis of dyspnea on exertion]. / Rasituslaryngoskopia: uusi menetelmä rasitushengenahdistuksen erotusdiagnostiikkaan.

Exertional dyspnea originating from the laryngeal level can be established with certainty only if the paradoxical vocal cord adduction is observed during dyspnea. We have developed a novel diagnostic method, exercise laryngoscopy, which involves observation of the larynx with a flexible endoscope applied via the nose during a bicycle ergometry test. It has been our aim to improve the differential diagnosis of dyspnea on exertion and thus also reduce unnecessary antiasthmatic medication. Exercise laryngoscopy allows examination in the out-patient clinics because the method is well tolerated.

Fiberoptic videolaryngoscopy during bicycle ergometry: a diagnostic tool for exercise-induced vocal cord dysfunction.

OBJECTIVES/HYPOTHESIS: Exercise-induced vocal cord dysfunction is difficult to diagnose because the paradoxical vocal cord adduction should be observed during exercise. Our goal was to develop and validate a new diagnostic method for exercise-induced vocal cord dysfunction by combining continuous fiberoptic laryngoscopy with a bicycle ergometry test. METHODS: Thirty consecutive patients referred to a laryngologist because of suspicion of exercise-induced vocal cord dysfunction and 15 healthy controls underwent the exercise test until dyspnea or exhaustion rated as 18-19/20 on the Borg scale. Laryngeal findings, electrocardiography, blood pressure, heart rate, and respiratory rate were monitored, and forced expiratory flow in the first second was measured before and after the exercise. The medical history was assessed by use of a structured questionnaire. RESULTS: Among the 30 patients, 27 (90%) performed the test successfully, as did all controls. Diagnostic signs of inspiratory stridor, supraglottic collapse, and vocal cord adduction appeared in five (19%) patients but in none of the controls. Of the 30 patients referred, the laryngologist considered 25 to be suspect. Of them, 9 (36%) showed signs diagnostic or highly suspect for exercise-induced vocal cord dysfunction. Of the 15 patients whose dyspnea could be induced during the test, nine (60%) were suspected of having exercise-induced vocal cord dysfunction. CONCLUSIONS: Fiberoptic videolaryngoscopy during bicycle ergometry was a well-tolerated and relatively easily established diagnostic tool that could induce dyspnea in more than one half the patients examined. If the symptom of dyspnea appeared, the most frequent diagnosis was exercise- induced vocal cord dysfunction.

A comparison of the effects of Voice Massage and voice hygiene lecture on self-reported vocal well-being and acoustic and perceptual speech parameters in female teachers.

This study compared the effects of Voice Massage (VM) and a voice hygiene lecture (VHL) on 60 female teachers. VM is a Finnish massage method which treats muscles related to voice production. All subjects attended the VHL (3 h). Half of them were randomly assigned to the VM group, the other half received only VHL. VM was given 5 times in 1-hour sessions at intervals of 1-2 weeks. At the beginning and end of the autumn school term, before and after a working day, (1) a 1-min reading sample was recorded at both the subject's habitual loudness and loudly, (2) a prolonged phonation on [a:] was recorded at habitual speaking pitch and (3) a questionnaire on voice quality, ease or difficulty of phonation, and tiredness of the throat was completed. The reading samples were analysed for the fundamental frequency (F0), equivalent sound level (Leq) and alpha-ratio [Leq (1-5 kHz)-Leq (50-1,000 Hz)]. The vowel samples were analysed for the F0 and Leq, as well as for jitter and shimmer. The reading samples were also evaluated perceptually by 3 speech trainers. The mean F0 and difficulty of phonation increased from the beginning to the end of the term in the VHL group (p = 0.026, p = 0.007, respectively). In the VM group, the perceived firmness of loud reading decreased (p = 0.026). The results suggest that VM may help in sustaining vocal well-being during a school term.

Pilot study on acute voice and throat symptoms related to exposure to organic dust: preliminary findings from a provocation test.

The aim of this pilot research was to investigate acute voice and throat symptoms related to organic dust exposure among nine subjects with suspected occupational rhinitis or asthma. Subjective voice and throat symptoms were recorded before and after an occupational exposure test. In addition, the study included perceptual assessment of subjects' voice samples recorded before and after the exposure tests. The results showed a number of (statistically) significant voice and throat changes in symptoms based on subjects' own assessments. These symptoms included a hoarse, husky, or tense voice, requiring an extra effort when speaking and difficulty in starting phonation (P < 0.05). Other significant symptoms included feeling of shortness of breath or the need to gasp for air and feeling that the voice is weak or that it does not resonate (P < 0.01). Such changes were not, however, detected by voice clinicians in the listening test of subjects' voice samples recorded before and after the exposure. These results suggest that the larynx reacts to organic dust with symptoms that are felt by the patient rather than heard by the voice clinician. The voice disorder in such cases is a diagnosis based on symptoms expressed by subjects.

Relationships between self-evaluations of voice and working conditions, background factors, and phoniatric findings in female teachers.

Self-evaluations of voice, working conditions, and results of phoniatric examination were studied in 78 female primary school teachers. Most teachers evaluated their vocal capabilities as 'normal'; nevertheless 1/3 reported two or more weekly symptoms. Unsatisfactory air quality, background noise, and stressful working conditions were seen as the most harmful environmental factors. A total of 14% of the subjects had organic laryngeal changes, 37% had mild changes, and 49% were found to be healthy. These findings did not correlate with self-evaluation of voice, vocal symptoms, or voice-related quality of life. Teaching experience or teaching hours per week did not correlate with laryngeal findings or symptoms. The results illustrate the complex nature of voice assessment and the need of assessment tools specially suited for functionally healthy voice professionals.

Effects of voice training and voice hygiene education on acoustic and perceptual speech parameters and self-reported vocal well-being in female teachers.

Voice education programs may help in optimizing teachers' voice use. This study compared effects of voice training (VT) and voice hygiene lecture (VHL) in 60 randomly assigned female teachers. All 60 attended the lecture, and 30 completed a short training course in addition. Text reading was recorded in working environments and analyzed for fundamental frequency (F0), equivalent sound level (Leq), alpha ratio, jitter, shimmer, and perceptual quality. Self-reports of vocal well-being were registered. In the VHL group, increased F0 and difficulty of phonation and in the VT group decreased perturbation, increased alpha ratio, easier phonation, and improved perceptual and self-reported voice quality were found. Both groups equally self-reported increase of voice care knowledge. Results seem to indicate improved vocal well-being after training.

Acoustic measures and self-reports of vocal fatigue by female teachers.

This study investigated the relation of symptoms of vocal fatigue to acoustic variables reflecting type of voice production and the effects of vocal loading. Seventy-nine female primary school teachers volunteered as subjects. Before and after a working day, (1) a 1-minute text reading sample was recorded at habitual loudness and loudly (as in large classroom), (2) a prolonged phonation on [a:] was recorded at habitual speaking pitch and loudness, and (3) a questionnaire about voice quality, ease, or difficulty of phonation and tiredness of throat was completed. The samples were analyzed for average fundamental frequency (F0), sound pressure level (SPL), and phonation type reflecting alpha ratio (SPL [1-5 kHz]-SPL [50 Hz-1 kHz]). The vowel samples were additionally analyzed for perturbation (jitter and shimmer). After a working day, F0, SPL, and alpha ratio were higher, jitter and shimmer values were lower, and more tiredness of throat was reported. The average levels of the acoustic parameters did not correlate with the symptoms. Increase in jitter and mean F0 in loud reading correlated with tiredness of throat. The results seem to suggest that, at least among experienced vocal professionals, voice production type had little relevance from the point of view of vocal fatigue reported. Differences in the acoustic parameters after a vocally loading working day mainly seem to reflect increased muscle activity as a consequence of vocal loading.

Changes in objective acoustic measurements and subjective voice complaints in call center customer-service advisors during one working day.

SUMMARY: The aim of this study was to investigate how different acoustic parameters, extracted both from speech pressure waveforms and glottal flows, can be used in measuring vocal loading in modern working environments and how these parameters reflect the possible changes in the vocal function during a working day. In addition, correlations between objective acoustic parameters and subjective voice symptoms were addressed. The subjects were 24 female and 8 male customer-service advisors, who mainly use telephone during their working hours. Speech samples were recorded from continuous speech four times during a working day and voice symptom questionnaires were completed simultaneously. Among the various objective parameters, only F0 resulted in a statistically significant increase for both genders. No correlations between the changes in objective and subjective parameters appeared. However, the results encourage researchers within the field of occupational voice use to apply versatile measurement techniques in studying occupational voice loading.

High-speed registration of phonation-related glottal area variation during artificial lengthening of the vocal tract.

Vocal exercises that increase the vocal tract impedance are widely used in voice training and therapy. The present study applies a versatile methodology to investigate phonation during varying artificial extension of the vocal tract. Two males and one female phonated into a hard-walled plastic tube (phi 2 cm), whose physical length was randomly pair-wise changed between 30 cm, 60 cm and 100 cm. High-speed image (1900 f/sec) sequences of the vocal folds were obtained via a rigid endoscope. Acoustic and electroglottographic signals (EGG) were recorded. Oral pressure during shuttering of the tube was used to give an estimate of subglottic pressure (Psub). The only trend observed was that with the two longer tubes compared to the shortest one, fundamental frequency was lower, open time of the glottis shorter, and Psub higher. The results may partly reflect increased vocal tract impedance as such and partly the increased vocal effort to compensate for it. In other parameters there were individual differences in tube length-related changes, suggesting complexity of the coupling between supraglottic space and the glottis.

Occupational voice complaints and objective acoustic measurements-do they correlate?

To enable the development of appropriate diagnostics and treatment for occupational voice disorders, this study addresses connections between subjective voice complaints and objective observations. The subjects of this study were 24 female customer advisors, who mainly use the telephone during their working hours. During one working day, at four different times, speech samples covering 20 minutes of telephone conversation by the customer service advisors (CSAs) were recorded. In addition, the CSAs filled in a questionnaire (visual analogue scale) concerning their voice problems. To represent the vocal symptoms three variables were used: vocal fatigue, hoarseness and a general sum-variable. A 5-minute sample was taken from recordings for further analyses. This included fundamental frequency, sound pressure level, alpha ratio (the ratio between the spectral energy below and above 1000 Hz) and number of vocal fold vibrations. In the objective acoustic measurements, it was found that fundamental frequency (F0) rose significantly during the working day. Also the self-reported voice symptoms increased significantly during the working day. However, correlations between vocal symptoms and acoustic measures were not found.

Voice symptoms of call-centre customer service advisers experienced during a work-day and effects of a short vocal training course.

Occupational voice users often suffer from voice symptoms to varying extents. The first goal of this study was to find out how telephone customer service advisers experience voice symptoms at different moments of the working day. The second goal was to investigate the effects of a short vocal training course arranged for telephone workers. The results indicate that although the subjects did not suffer from severe voice problems, the short vocal training course significantly reduced some of the vocal symptoms they had experienced. The results suggest that systematic consultation and training for occupational voice users in the field of occupational voice care would be advantageous.

Immediate effects of 'voice massage' treatment on the speaking voice of healthy subjects.

'Voice massage' (VM) treatment includes manipulation of muscles related to speech production and voice and breathing exercises. This study investigated the effects of VM in 10 healthy subjects (5 females, 5 males). They recorded repetitions of the word 'paappa' at normal loudness and as softly as possible and read a text sample before and after 1-hour (1) VM treatment, (2) fast walking, (3) sitting in a library and (4) lying on a bed. Subglottic pressure was estimated from oral pressure during [p]. Transglottal flow and glottal resistance were measured. Voice production was studied with electroglottography. Fundamental frequency, sound pressure level (SPL) and alpha ratio [(SPL of the range 1-5 kHz) - (SPL of the range 50 Hz-1 kHz)] were calculated from text samples, which were also evaluated by 7 voice experts. A questionnaire was used to record subjects' sensations. Changes after lying and sitting suggest lowered effort in phonatory muscles, while after fast walking effort seemed to increase. After VM no significant changes were observed in voice parameters or perceptual quality, but ease of phonation and reduced tension in the neck, shoulders and back were reported. The effects of VM may be partly psychological, partly related to a search of phonatory balance.

Automatic speaking valve in speech rehabilitation for laryngectomized patients.

For speech rehabilitation after total laryngectomy, the Provox FreeHands Heat and Moisture Exchanger (FreeHands HME; Atos Medical AB, Hörby, Sweden) was compared with the Provox Heat and Moisture Exchanger (HME), and the patients' Health-Related Quality of Life (HRQoL) was assessed. A review of the English literature was performed considering automatic speaking valves. The study design was a cohort study. Fourteen laryngectomized male patients who had used the HME successfully before receiving the FreeHands HME entered the study. An ENT specialist and a speech pathologist examined these patients. Data concerning voicing, breathing, skin adhesion, voice and speech quality, and HRQoL were collected by a structured questionnaire. Voice recordings were performed for evaluation of the quality of the voice. A computer-aided search of the MED-LINE database was conducted, supplemented by hand searches of key journals. Twelve patients had used the FreeHands HME on special social occasions and reported three main reasons why FreeHands HME was unsuitable for continuous use: heavier breathing, more difficult speaking, and worse subjective quality of voice. With HME, phonation time tended to be longer and the softest phonation softer ( P =0.034). The loudest phonation was louder with FreeHands HME ( P =0.015). Patients' HRQoL assessed by the 15D profile was similar to that of the age- and sex-matched male Finnish general population (patients 0.877, population 0.884). A review of the literature showed few works dealing with automatic speaking valves. The FreeHands HME is a useful additional device in a selected group of laryngectomized patients. Total laryngectomy did not lower patients' HRQoL notably.

Occupational safety and health aspects of voice and speech professions.

A well-functioning voice is an essential tool for one third of the labour force. Vocal demands vary to a great extent between the different voice and speech professions. In professions with heavy vocal loading (e.g. school and kindergarten teachers), occupational voice disorders threatening working ability are common. Vocal loading is a combination of prolonged voice use and additional loading factors (e.g. background noise, acoustics, air quality) affecting the fundamental frequency, type and loudness of phonation or the vibratory characteristics of the vocal folds as well as the external frame of the larynx. The prevention and treatment of occupational voice disorders calls for improved occupational safety and health (OSH) arrangements for voice and speech professionals. On the basis of epidemiological and acoustic-physiological research, the presence of risk to vocal health can be substantiated. From the point of view of the physical load on the vocal apparatus, loading-related physiological changes (adaptation) may play a role in the occupational risk. Environmental factors affect vocal loading changes. In teaching professions, the working environment is shared with children, who benefit from amendments of OSH legislation concerning their teachers.

Estimating perceived phonatory pressedness in singing from flow glottograms.

The normalized amplitude quotient (NAQ), defined as the ratio between the peak-to-peak amplitude of the flow pulse and the negative peak amplitude of the differentiated flow glottogram and normalized with respect to period time, has been shown to be related to glottal adduction. Glottal adduction, in turn, affects mode of phonation and hence perceived phonatory pressedness. The relationship between NAQ and perceived phonatory pressedness was analyzed in a material collected from a professional female singer and singing teacher who sang a triad pattern in breathy, flow, neutral, and pressed phonation in three different loudness conditions (soft, middle, loud). In addition, she also sang the same triad pattern in four different styles of singing, classical, pop, jazz, and blues, in the same three loudness conditions. A panel of experts rated the degree of perceived phonatory press along visual analogue scales. Comparing the obtained mean rated pressedness ratings with the mean NAQ values for the various triads showed that about 73% of the variation in perceived pressedness could be accounted for by variations of NAQ.

Automatic pre-segmentation of running speech improves the robustness of several acoustic voice measures.

In order to study vocal loading, we developed a speech analysis environment for continuous speech. The objective was to build a robust system capable of handling large amounts of data while minimizing the amount of user-intervention required. The current version of the system can analyze up to five-minute recordings of speech at a time. Through a semiautomatic process it will classify a speech signal into segments of silence, voiced speech and unvoiced speech. Parameters extracted from the input signal include fundamental frequency, sound pressure level, alpha-ratio and speech segment information such as the ratio of speech to silence. This paper presents results from the performance evaluation of the system, which shows that the analysis environment is able to perform robust and consistent measurements of continuous speech.