Maximum Phonation Time Values Research Articles

Maximum Phonation Time of School-Aged Children in Pakistan: A Normative Study

Maximum phonation time (MPT) evaluates maximum vocal capabilities and can be used to assess the effectiveness of behavioral and medical therapy interventions. There is a literature gap regarding MPT normalcy data for Pakistani children. Objective: To determine the Maximum Phonation Time of School Aged Children in Pakistan and its association with participant variables and impact of the 6-minute walk test on participant vitals. Methods: This cross-sectional survey was conducted in Rawalpindi and Islamabad on typical healthy school-aged children from August 2021 to January 2022. The sample included both genders, aged 6-13 years having normal language. Tools used included a basic demographic sheet, token test, stopwatch, growth chart, sphygmomanometer, pulse oximeter, and 6-minute walk test. Blood Pressure, oxygen saturation, heart rate, and MPT were calculated before and after the six-minute walk test (6-MWT). Data were analyzed by using SPSS version 21.0. Results: Results show MPT of 13.11 ± 3.93 seconds. Scores were significantly (p= 0.000) higher for higher age groups. 6-MWT revealed a significantly (p=0.000) higher post walk SPO2 (99.16 ± 0.89 Vs.97.82 ± 1.45), HR (105.94 ± 14.53 vs 92.94 ± 14.79). systolic (112.46±13.40 vs. 107.25 ± 13.66) and diastolic blood pressure (79.07 ± 8.17 Vs.73.84 ± 8.50) compared to pre walk. A significantly (p<0.001) strong positive correlation was noted for age(r=.515), weight (r=.460), height (r=.491) and distance (r=.281). Conclusions: MPT of Pakistani 6-13 years children is 13.11 ± 3.93 seconds with significantly higher MPT for higher age groups. MPT has a strong positive correlation with age, weight, height and distance and increases after walking. MPT values for boys were slightly higher than for girls.

Analysis of swallowing and voice-related quality of life in patients after supracricoid partial laryngectomy

ObjectiveThis study evaluated the swallowing and voice function of laryngeal cancer patients after Supracricoid Partial Laryngectomy(SCPL), and its influence on quality of life to provide a reference for the selection of surgical methods for laryngeal cancer patients.MethodsTwenty-one patients who received SCPL between April 2015 and November 2021 were included. Each patient’s swallowing function and quality of life were assessed through fiberoptic endoscopic examination of swallowing (FEES) and the M.D. Anderson Dysphagia Inventory (MDADI). Fundamental, jitter, shimmer, maximum phonation time (MPT), and voice handicap index-10 (VHI-10) were performed to assess voice function and voice-related quality of life.ResultsThe results of the FEES of the 21 patients were as follows: the rates of pharyngeal residue after swallowing solid, semiliquid, and liquid food were 0%, 28.57%, and 38.09%, respectively; the rates of laryngeal infiltration after swallowing solid, semiliquid, and liquid food were 0%, 28.57%, and 4.76%, respectively; and aspiration did not occur in any of the patients. In the evaluation of swallowing quality of life, the mean total MDADI score was 92.6 ± 6.32. The voice function evaluation showed that the mean F0, jitter, shimmer, and MPT values were 156.01 ± 120.87 (HZ), 11.57 ± 6.21 (%), 35.37 ± 14.16 (%) and 7.85 ± 6.08 (s), respectively. The mean total VHI-10 score was 7.14 ± 4.84.ConclusionSCPL provides patients with satisfactory swallowing and voice function. The patients in this study were satisfied with their quality of life in terms of swallowing and voice. SCPL can be used as a surgical method to preserve laryngeal function in patients with laryngeal cancer.

Effect of Akson Therapy on Acoustic Parameters in Patients with Functional Dysphonia.

Functional dysphonia can impair the language expression ability and adversely affect the career development of some patients. Therefore, an active exploration of effective treatment options is imperative. This study investigated the effect of Akson therapy on acoustic parameters in patients with functional dysphonia. In this retrospective analysis, 79 patients with functional dysphonia who received conventional voice correction training from June 2020 to June 2021 were included in the reference group (RG). Our hospital has implemented Akson therapy since July 2021. Correspondingly, 72 patients with functional dysphonia who underwent Akson therapy from July 2021 to July 2022 were enrolled in the observation group (OG). The acoustic parameters such as fundamental frequency (F0), jitter, shimmer, and normalized noise energy (NNE); the aerodynamic parameters including maximum phonation time (MPT), mean airflow rate (MFR), and Voice Handicap Index-10 (VHI-10) score; and the Grade, Roughness, Breathiness, Asthenia, and Strain scale (GRBAS) score were measured before and after treatment and compared between the two groups. The F0, jitter, shimmer, NNE, MPT, and MFR values as well as the VHI-10 score and the grade (G), roughness (R), and breathiness (B) scores on the GRBAS did not significantly differ between the two groups before treatment (P > 0.05). However, significantly lower F0, jitter, shimmer, NNE, and MFR values and higher MPT levels were found in the OG compared to the RG after treatment (P < 0.001). Furthermore, the VHI-10 score and the G, R, and B scores were significantly lower in the OG than in the RG after treatment (P < 0.001), whereas the asthenia (A) and strain (S) scores remained at 0 before and after treatment. Akson therapy can improve the acoustic parameters of patients with functional dysphonia to a certain extent, indicating its potential application value.

Vocal Impact in Patients With Unilateral Diaphragmatic Paralysis

This study aimed to investigate the possible vocal impact confirmed by diagnostic tests, the degree of perception of possible vocal impairment by patients with Unilateral Diaphragmatic paralysis (UDP) and its correlation with ventilatory weakness. The researchers conducted an analytical, observational and case-control study with 70 individuals, including 35 UDP patients and 35 healthy patients in a control group, who underwent the following assessments: 1) Self-assessment of voice handicap (VHI-10); 2) Self-Assessment of Quality of Life (SF-36); 3) Self-Assessment of Dyspnea (MRC); 4) Objective vocal measures (Maximum Phonation Time (MPT) in /a/, /s/, /z/ and glottal-to-noise excitation ratio); 5) Functional respiratory pressures (Spirometry and maximum ventilatory pressures); 6) General degree of dysphonia - G on the GRBAS Scale. The sex, age and body mass index (BMI) of the individuals were the variables used to match the sample of this study. When compared with controls, patients with UDP had a restrictive functional pattern and inspiratory weakness, with symptoms of dyspnea and worsening quality of life. When associated with a possible vocal impact, these patients had voice handicap and decreased MPT values for all phonemes, especially /a/. There was also a correlation between vocal performance and inspiratory weakness. However, it should be noted that, despite having vocal impairment, many patients did not report the perception of this fact, somehow neglecting such impairment. In addition to the expected weakness of the ventilatory muscles, patients with UDP had clinically verified vocal impact, and those who had greater inspiratory weakness also had greater voice impairment. Finally, it is relevant that not all patients perceived such vocal impact, which showed a very reduced perception of this impairment in patients with UDP.

Effects of Diaphragmatic Breathing Exercise on Respiratory Functions and Vocal Sustenance in Apparently Healthy Vocalists

Effective vocalization is dependent on breathing efficiency. Previous studies have reported the efficacy of Diaphragmatic Breathing Exercise (DBE) on the respiratory muscles and breath control of vocalists. There is a paucity of data on the effects of DBE on their vocal sustenance (VS), which is determined as Maximum Phonation Time (MPT). No known published study has considered physiotherapy as influencing voice dynamics amongst vocalists; evaluated the relationship between respiratory functions (Forced Vital Capacity - FVC, Forced Expiratory Volume in one second - FEV1, FEV1/FVC, and Peak Expiratory Flow - PEF) and VS in apparently healthy vocalists. Moreover, literature on the benefits of DBE to vocalists has not considered explicitly this aspect of vocalization skill, VS. This is a pre-test - post-test experimental study involving a total of 37 participants (17 males and 20 females) selected by purposive and convenience sampling techniques. The subjects were grouped into DBE and control groups. Spirobank MIR spirometer was used to assess the respiratory function of the singers, while a stopwatch and keyboard were used in assessing the MPT. Statistical analysis was done with SPSS version 21.0. Alpha level set at 0.05. Significant improvement was found in respiratory functions (FVC, FEV1, FEV1/FVC, PEF) of the DBE group when pre- and post-test results were compared. The DBE and control groups differed significantly. Respiratory values correlated significantly with the MPT values (FVC - r[p] - 0.416[0.011]; FEV1 - r[p] - 0.416[0.010]; PEF - r[p] - 0.566[0.000]), except for FEV1/FVC - r(p) - 0.248(0.138). Voice category did not correlate with respiratory parameters or MPT. While male singers showed more changes in respiratory function the female singers showed more improvement in MPT. DBE can improve respiration and VS (increased MPT). Therefore, it can be recommended for vocalists, and Physiotherapy can be relevant in trainings to improve vocal dynamics.

Relationship between dysphonia and anxiety in fibromyalgia syndrome.

Our aim in conducting this study is to determine the relationship dysphonia and anxiety in patients with fibromyalgia syndrome (FS). Between April 2021 and June 2021, 25 FS diagnosed patients (22 females, 3 males; mean age: 45.36 ± 7.68years; range 27-65years), and, for the control group, 25 healthy volunteers (20 females, 5 males; mean age: 42.60 ± 9.98years; range 29-62years) with similar demographic features were included in the study. Visual Analog Scale (VAS), Beck Anxiety Questionary (BAQ), and voice analyses were evaluated for all the participants. Acoustic parameters (AP), such as F0 (Hz), jitter (%), shimmer (%), and Maximum Phonation Time (MPT), were measured for dysphonia. The correlation between MPT and BAQ was evaluated. The demographic characteristics of the groups did not differ statistically significantly (p > 0.05). VAS and BAQ scores were statistically significantly higher in the FS group than healthy individuals. In the assessment of sound, there was no significant difference between F0 and jitteriness between the two groups. While shimmer scores were significantly higher in the FS group, MPT scores were statistically significantly higher in healthy individuals. In our study, we observed that FS patients had statistically significantly higher BAQ, VAS scores compared to the control group. The shimmer of voice was increased and MPT values were decreased statistically significantly in FS patients. This says that there may be weakness in the laryngeal muscles affecting the vocal cord and thus voice quality. In addition to this, increased anxiety in FS patients may be associated with dysphonia. There is need for more controlled studies with increased number of patients to investigate the dysphonia in FS patients.

Comparison of Client-Led Asynchronous and Clinician-Led Synchronous Online Methods for Evaluation of Subjective Vocal Measures in Teachers: A Feasibility Study

COVID-19 has transformed face to face teaching in classrooms to online and hybrid modes. Increased vocal intensity/ pitch to call attention of students and transact in the online class, inappropriate posture (head, neck & upper trunk) while using the laptop and other online tools cause vocal loading leading to voice related concerns in teachers. Tele voice assessment is a feasible alternative means to seek professional help in the current situation and possibly in the future too. Client-led asynchronous and clinician-led synchronous voice recordings for clinical vocal measures among school teachers were compared in this study. Twenty-five school teachers (21 females & four males) from Chennai consented to the study. Information of voice use, its impact on the day-to-day situations, self-perception of vocal fatigue, and their recorded voice sample (phonation & speaking) were obtained online (asynchronous mode). Within a period of ten days, the clinician-led synchronous session was planned on a mutually convenient time for obtaining voice samples through zoom call. The voice samples obtained were compared for clinical measures and perceptual voice evaluation. Participants reported of vocal symptoms and increased vocal fatigue scores. The maximum phonation time values obtained through synchronous mode were lesser when compared to asynchronous mode. Also, variability was noted in the perceptual vocal measures of voice samples obtained through synchronous mode. During synchronous voice recording & evaluation, the background noise, internet stability, audio enhancement feature, and microphone placement & quality could be monitored, and immediate feedback was provided. Additionally, the asynchronous recording can be supplemented for synchronous recording, with clear instructions & demonstration. This study explored the feasibility of using synchronous and asynchronous voice recording for voice analysis in school teachers. The findings could serve as a base to understand the advantages and challenges of using client-led asynchronous and clinician-led synchronous methods for estimating vocal measures.

Maximum Phonation Time is a Useful Assessment for Older Adults Requiring Long-term Care/support.

The maximum phonation time (MPT) is used to assess simple respiratory functions and can be performed anywhere without special instruments. We investigated the association between MPT and respiration, considering the future utilization of simple respiratory assessments during home-based physical therapy. This cross-sectional study included 140 older adults enrolled in Japanese long-term care insurance (77 men, 63 women; mean age, 77.9±8.0 years). The participants performed the MPT, followed by spirometry. We analyzed the MPT of the three age groups, relative reliability of the MPT values, and the association between MPT and respiratory function. We found that the MPT of older men requiring long-term care or support was related to age. The intraclass correlation coefficient of MPT was >0.8 for all groups. Only forced vital capacity was associated with MPT in the partial correlation and multiple regression analyses. MPT could be an alternative assessment of respiratory function in home-based physical therapy for older adults requiring long-term care or support.

Voice and Swallowing Disorders After Thyroid Surgery

The aim of the study was to evaluate voice and swallowing function following thyroid surgery, to identify dynamic changes during the follow-up period of 12-18 month and to find possible indicative signs of permanent or temporary vocal fold palsy. All participants (N=110) were prospectively enrolled from the preoperative thyroid surgery patients between September 2013 and December 2016. All subjects underwent preoperatively, first week and 12-18 month postoperatively videolaryngostroboscopy, filled in subjective evaluation of voice (voice handicap index, [VHI]) and swallowing (swallowing impairment score) complaints. Acoustic voice analysis (AVA), maximum phonation time (MPT) measurement and perceptual voice evaluation were conducted. In the presence of laryngeal damage, additional first and sixth-month follow-up visits were planned. Patients, whom we suspected laryngeal nerve damage, underwent laryngeal electromyography 4 weeks after the operation. On first postoperative week evaluation, no objective voice changes within patients with postoperatively intact laryngeal nerves were found. Subjective evaluations showed decline in VHI physical domain and increased strain in postoperative voice. Patients with postoperative nerve damage had a drastic decline in subjective voice quality (VHI all subscales and total score), AVA parameter jitter, MPT and perceptual voice quality. Subjective evaluation of swallowing revealed disturbances in all patients regardless of the nerve damage. We noticed remarkable differences in first week and first month visits between patients with permanent and temporary palsy in VHI total score and physical domain, MPT and perceptual breathiness and asthenia in voice. Regardless of the nerve injury, by the end of the follow-up period all changes had become statistically insignificant with the exception of perceptual evaluation of voice quality. Patients with postoperative laryngeal nerve damage experience substantial deterioration of both subjective and objective voice quality with more extensive impairment in patients with permanent paralysis. Thyroid surgery causes subjective swallowing changes irrespective of laryngeal nerve damage. In patients without laryngeal nerve damage, swallowing function improves following thyroidectomy. Possible indicators for permanent paralysis are delayed recovery in the values of MPT and jitter and persistent perceptual breathiness and asthenia.

Quantitative Measurement of Dysphonia Severity in Patients With Stroke With Unilateral Vocal Cord Palsy.

Unilateral vocal cord palsy (UVCP) is frequently observed in patients with stroke. This study aimed to evaluate the association between objective dysphonia severity and the classification of UVCP in patients with stroke by objectively and quantitatively measuring their phonetic function. We recruited patients with UVCP diagnosed using laryngoscopy after stroke. Subgroups were divided according to UVCP type, and the dysphonia severity index (DSI) and maximum phonation time (MPT) were measured to objectively evaluate dysphonia. The DSI and MPT were compared between subgroups using analysis of variance with Tukey's honest significant difference post hoc test. In total, 103 patients with stroke and UVCP were recruited. We found that a higher UVCP severity possibly had to do with lower DSI and MPT values. We objectively confirmed that phonetic function was worse in patients with stroke with higher UVCP severity, and the DSI and MPT tests can be helpful in determining the severity and need for additional evaluation.

Voice Outcome After Cold Knife Surgery According to the Characteristics of Vocal Fold Polyp

Voice change is one of the major symptoms in patients with vocal fold polyp. As a result, phonomicrosurgery is commonly required in these patients. Since voice outcomes after polyp treatment can be variable according to polyp characteristics, we aimed to investigate the predicting factors of postoperative voice improvements in terms of polyp characteristics in patients with vocal fold polyp who underwent cold knife surgery. A total of 77 patients who were diagnosed with vocal fold polyp and underwent phonomicrosurgery with cold knife instruments. The polyp characteristics of color, size, shape, and location were evaluated at baseline. Acoustic and aerodynamic analyses, voice handicap index questionnaire and grade, roughness, breathiness, asthenia, strain scale were evaluated at baseline and 6 weeks after surgery. All values of postoperative voice parameters improved after cold knife surgery. (P < 0.05) In patient with an organized vocal fold polyp, less improvement in postoperative values of maximum phonation time were observed. (P < 0.05) Likewise, less improvement of voice handicap index questionnaire score and grade, roughness, breathiness, asthenia, strain scale after surgery was shown in organized vocal fold polyp. (P < 0.05) CONCLUSIONS: Among the various polyp characteristics, the organized polyp was significantly related to relatively less improvement of objective and subjective voice parameters after surgery. These polyp characteristics would help to predict postoperative voice improvement and plan for personalized treatment in patients with vocal fold polyp.

Do Flexible Silicone Tubes Immersed in Water Combined With Vocalise Improve the Immediate Effect on Voice?

This study aimed to analyze the immediate effect on a singer's voice of a flexible silicone tube immersed in water combined with ascending and descending vocalise scales compared with ascending and descending vocalise scales alone. A pre- and post-intervention quasi-experimental study was conducted. Thirty adult singers between 18 and 45 years old with no laryngeal disorders performed the two techniques for 3 min each on different days. Acoustic measurements of frequency, jitter, shimmer, glottal-to-noise excitation ratio, noise, smoothed cepstral peak prominence (CPPS), maximum phonation time (MPT), voice range profile, and self-perceived vocal effort (Borg Category Ratio 10-BR Scale adapted for vocal effort) were assessed before and after performing the techniques. The results indicated an increase in singers' CPPS and MPT values and a decrease in shimmer and noise when performing with a flexible silicone tube immersed in water combined with vocalise. The singers reported a perception of decreased vocal effort after both methods. However, the diminished perceived vocal effort became more pronounced with the tube phonation technique combined with vocalise. Phonation in tubes combined with vocalise improved the vocal acoustic parameters (including cepstral measurements), increased MPT, and diminished perceived vocal effort. Although using vocalise alone diminished perceived vocal effort, this decrease was more pronounced in the tube phonation technique combined with vocalise.

The Effect of Masks and Respirators on Acoustic Voice Analysis During the COVID-19 Pandemic.

ObjectivesWorld Health Organization declared the coronavirus disease (COVID-19) as a global pandemic on March 11, 2020. The aim of this study was to determine the effectiveness and reliability of voice analysis performed with surgical masks and respirators during the pandemic and to discuss its routine applicability.MethodsThis prospective study included 204 patients who applied to our clinic between the ages of 18 and 55, whose preoperative SARS-Cov-2 PCR tests were negative. Voice analyses were performed on each patient without a mask, with a surgical mask and with a valved face-filtering piece-3 (FFP3) respirator respectively. The F0, shimmer, jitter, s/z ratio, maximum phonation time and harmonic/noise ratio (HNR) values obtained from the voice analyses were compared with each other.ResultsNo significant difference was found in terms of F0, Jitter, Shimmer, HNR, s/z and maximum phonation time values in the voice analyses performed without a mask and with a surgical mask. With an FFP3, a significant difference was found in only the Shimmer and HNR values compared to the other analysis values. When we look at the data with sex distinction, in the group of female and male patients, when the data of voice analysis obtained in three situations were compared, different results were obtained from the female and male group.ConclusionIn conclusion, it should be decided by the physician to perform the voice analysis with a surgical mask or with an FFP3, considering the clinically desired parameters.

The Effectiveness of Rehabilitation of Occupational Voice Disorders in a Health Resort Hospital Environment.

Background: The aim of this study was to present a rehabilitation program of occupational voice disorders for teachers, conducted in the form of health resort stays, and evaluate its effectiveness depending on job seniority. Methods: The study included 420 teachers who participated in a complex vocal prophylactic and rehabilitation program carried out during a 24-day stay at a health resort hospital. Employment time varied from 4 to 45 years (mean 28.3 years). The participants were divided into three groups: employment time < 21 years (57 teachers), 21–30 years (182 teachers) and > 30 years (181 teachers). All of the subjects underwent maximum phonation time assessment as well as jitter, shimmer and NHR (noise to harmonic ratio) parameters assessment before and after the program; they also underwent perceptual evaluation using the GRBAS scale and voice self-assessment using the VHI-30 scale. Results: The perceptual evaluation using the GRBAS scale and self-report measures of voice function assessed using the VHI scale revealed improvement (p < 0.001). The parameters of jitter, shimmer and NHR improved significantly: jitter p < 0.001, shimmer p < 0.001 and NHR p < 0.003. Maximum phonation time increased slightly but significantly (p < 0.001). For all of the studied groups regardless of their employment time, maximum phonation time increased (p < 0.001). Initially, the lowest values of maximum phonation time were observed in teachers with longer job seniority, which improved after the rehabilitation but remained <15 s. Conclusions: Voice care for teachers is crucial regardless of their job seniority. Early prophylaxis for voice disorders is effective, as the results of rehabilitation are better in teachers with a shorter employment time.

Does Abrupt Weight Loss Caused by Bariatric Surgery Compromise the Voice in Women?

To evaluate vocal symptoms, voice characteristics and videolaryngoscopy in obese women before and after bariatric surgery. Obese patients (18 to 59 years old), candidates for bariatric surgery were recruited. Evaluation times: T1 (preoperative), T2 (after six months), T3 (after 12 months). Evaluated parameters: weight, height, body mass index, abdominal and neck circumference, vocal self-assessment, perceptual and acoustic vocal assessment, and videolaryngoscopy. A total of 37 obese women were included, average age 40.8 years. There was a decrease in anthropometric measurements between the preoperative assessment and after 12 months: weight (121.18 ± 15.4 kg; 77.1 ± 11.6 kg), BMI (46.6 ± 6.95 kg/m2; 30 ± kg/m2), abdominal circumference (128 ± 16.1; 99.1 ± 12.1), and neck circumference (41.1 ± 5.85; 36.6 ± 3.02). Gastroesophageal (21.6%) and vocal symptoms (27%) prevailed. No difference was identified in vocal self-assessment between the evaluations. In the acoustic analysis, f0 increased and the soft phonation index decreased. The perceptual analysis registered lower scores for the degree of dysphonia (G) and voice instability (I). The maximum phonation time values increased without changing the s/z ratio. Videolaryngoscopies showed a posterior middle cleft and improvement in the signs of reflux. Bariatric surgery led to an important and gradual decrease in anthropometric parameters. The voice became less hoarse, with higher pitch and more stable, with an improvement in maximum phonation time, however with slight breathiness. Such changes were not noticed by the patients.

Impact of Allergic Rhinitis on Voice in Children

Introduction: The purpose of the present study was to determine the possible effect of allergic rhinitis (AR) on voice change in children with acoustic analysis and Turkish children’s voice handicap index-10 (TR-CVHI-10). Methods: This is a case-control study. Forty-one children with AR, and a positive skin prick test, as well as 39 children of controls who had produced a negative skin prick test and lacked a history of allergic disease, were selected for the study. Each assessment included recordings for the purposes of acoustic voice analysis (fundamental frequency [f0], jitter %, shimmer %, and harmonics-to-noise ratio (HNR)), and aerodynamic analysis (maximum phonation time (MPT) and s/z ratio). All participants completed TR-CVHI-10. Results: The mean TR-CVHI-10 score of the AR group was significantly higher than the control group (p = 0.013). No difference was observed between the AR and control groups in terms of jitter, shimmer, HNR, and MPT values and s/z ratio (p > 0.05). Conversely, the f0 value was more pronounced in controls (270.9 ± 60.3 Hz) than in the AR group (237.7 ± 54.3 Hz) (p = 0.012). Conclusion: The study’s results revealed that AR can have an effect on fundamental frequency and voice quality in children. The diagnostic process should include AR as a potential cause of voice disorders in children.

Maximum Phonation Time Normative Values Among Malaysians and Its Relation to Body Mass Index

Maximum phonation time (MPT) is a test to measure glottic efficiency for laryngeal pathology screening and treatment monitoring. The normative value of MPT for South East Asia population has yet to be reported. It is postulated that MPT may be affected by body mass index (BMI) despite the paucity of evidence. Therefore, this study was designed to establish the normative value of MPT for a South East Asia population and investigate its relation to BMI. This cross-sectional study was conducted in Universiti Kebangsaan Malaysia Medical Center between May and September 2017. Three hundred males and females with mean age of 30.23 (±11.04) years were recruited in equal number for each gender (n=150) and divided into 3 groups of 50 according to their BMI (n=50). The three groups are non-obese (BMI≤22.9kg/m2); obese (BMI between 23 and 34.9 kg/m2); and morbidly obese (BMI >35kg/m2). BMI and Voice Handicap Index-10 (VHI-10) were obtained. The average of three readings of MPT was measured using a stopwatch while the participants phonate /a/, /i/ and /u/. Unpaired t-test and ANOVA were used to compare means between and across groups. Spearman correlation assessed the correlation between MPT and BMI. The normative values of MPT of both genders and correlation with BMI were analyzed. The MPT normative values for males and females in the non-obese group were of 21.41 (±6.85) seconds and 18.05 (±5.06)seconds respectively for /a/. The MPT for all vowels were significantly higher in males across the BMI groups (P ≤ 0.05). There was low negative correlation between MPT and BMI in both genders. This pioneering study documented the normative values of MPT among Malaysians showed that males had longer MPT than females across the BMI groups. Obesity affects the MPT in that as BMI increases, the MPT decreases.

Characteristics of the Voice of Dysphonic School Children from 4:0 to 7:11 Years Old

Childhood dysphonia is frequent and has many origins, with the most common initial symptom being the altered vocal quality. Describe and correlate the auditory-perceptual and acoustic characteristics of the voice, and the maximum phonation time (MPT), of dysphonic schoolchildren from private and public schools from 4:0 to 7:11 years old, female and male. MPT, acoustic (Multi-Dimensional Voice Program Advanced and Real Time Spectrogram), and auditory-perceptual (Consensus Auditory-Perceptual Evaluation of Voice) evaluations of 115 schoolchildren were statistically analyzed. Auditory-perceptual parameters values were classified as mild, and MPT values were reduced, in most children. Fundamental frequency and Jitt values decreased significantly with age; MPT/i/ increased significantly with age. Relative average perturbation, voice turbulence index (VTI), and number of sub-harmonic segments values were significantly higher in 4:0 years old children. The number of unvoiced segments was higher in 6:0 years old children. Shimmer percent was higher in 7:0 years old children. There were negative correlations between the high frequency spectrographic tracing color intensity and the vocal strain; the VTI and the MPT; the degree of unvoiced segments and the MPT. There was a positive correlation between the smoothed pitch period perturbation quotient and the roughness. In dysphonic schoolchildren, auditory-perceptual parameters were moderate, MPT was reduced, several acoustic parameters were altered, and these vocal characteristics improved with age.

Maximum Phonation Time and Body Mass Index in Nondysphonic Eutrophic Children

Literature presents controversial maximum phonation time values in children. Verify and correlate the maximum phonation time of vowels /a, i, u/ and the body mass index of children. Evaluation of 484 children, eutrophic and without dysphonia, aged from 4:00 to 7:11 years. questionnaire, audiometric screening, auditory-perceptual evaluation of voice, and assessment of the body mass index. measurement of the maximum phonation time of /a, i, u/. Descriptive statistics, t test, and multiple regression at 5% significance. /a:/ = 3.77 seconds at age 4:00 years, 5 seconds at 5:00, 5.85 seconds at 6:00, and 7.5 seconds at 7:00 for boys, and 3.89 seconds, 4.89 seconds, 5.61 seconds, and 6.61 seconds for girls, respectively; /i:/ = 3.49 seconds at age 4:00 years, 4.96 seconds at 5:00, 5.72 seconds at 6:00, and 6.88 seconds at 7:00 for boys, and 3.49 seconds, 4.73 seconds, 5.41 seconds, and 6.63 seconds for girls, respectively; /u:/ = 3.64 seconds at age 4:00 years, 4.85 seconds at 5:00, 5.76 seconds at 6:00, and 7.08 seconds at 7:00 for boys, and 3.54 seconds, 4.73 seconds, 5.64 seconds, and 6.47 seconds for girls, respectively. There were no significant differences between genders, except for /a:/ at age 7:00 years. The correlations were not significant. Maximum phonation time of /a, i, u/ increased with age and its value in seconds was approximately equal to the age in years. At the age 7:00 years, /a:/ from boys was longer. The body mass index did not show influence on the maximum phonation times.

The effect of electrolyte balance on the voice in hemodialysis patients.

The aim of the study was to demonstrate the effect of blood electrolytes on the voice in chronic hemodialysis patients. The study included a total of 59 hemodialysis patients. Pre- and post-dialysis voice recordings were performed. In the analysis of vocal acoustic parameters, fundamental frequency (F0), jitter, shimmer, the noise-to-harmonics ratio (NHR), and F0 minimum and F0 maximum were measured. The Voice Handicap Index-10 (VHI-10), and maximum phonation time (MPT) were evaluated. For perceptual evaluation, the GRBAS scale was used. The duration of dialysis (years) and changes in weight during dialysis were recorded for each patient. From venous blood samples, measurements were taken of hemoglobin (Hb), albumin, Na+, K+, creatinine, uric acid, phosphorus, Ca++, and parathormone. The difference in the pre and post-dialysis values of F0, shimmer, NHR and MPT were found to be statistically significant (p = 0.001). The only variable determined to have an effect on the change in F0 values was uric acid, and the change in the F0 values was statistically significant (p = 0.009). The only variable determined to have an effect on the change in shimmer values was sodium, and the change was statistically significant (p = 0.034). The only variable determined to have an effect on the change in NHR values was creatinine, and the change in the NHR values was statistically significant (p = 0.028). Hb and the duration of dialysis were determined to have a statistically significant effect on the change in MPT values (p = 0.001). The results showed that uric acid was the agent creating a reduction in vocal cord vibration, the agent increasing the difference between vibration waves was Na+, and creatinine increased the NHR rate. The effect of these variables can be considered important in the understanding of vocal cord physiology.