Correlation between voice intensity and swallowing function in subjects with Parkinson's disease.

INTRODUCTION: People with Parkinson's Disease (PD) experience reduced voice intensity and dysphagia. Organs related to voice production and swallowing are structurally and neurologically intertwined. Thus, instrumental voice assessment may be useful in identifying voice impairments that can show swallowing disorders. Timely assessment of swallowing disorders may prevent the occurrence of malnutrition, dehydration, pneumonia, and death. OBJECTIVE: The aim of this study was to investigate the relationship between voice intensity and swallowing function in PD. METHODS: 30 participants with PD were recruited. Motor disability was evaluated by the Unified Parkinson's Disease Rating Scale part III; voice intensity was assessed by PRAAT software during sustained /a/ and 1 min of monologue. The Penetration Aspiration Scale, the Dysphagia Outcome Severity Scale, and the Videofluoroscopic Dysphagia Scale were used to assess swallowing during videofluoroscopy. Spearman correlation coefficients, logistic, and linear models were used to analyze data. RESULTS: Voice intensity correlated with swallowing: as voice intensity decreased, swallowing function deteriorated (Spearman coefficients from -0.42 to -0.72 across scales), and this holds even when adjusted for MDS-UPDRS motor scores. Swallowing impairment is 56 times more likely (p<0.01) when the voice intensity is below the normal cut-off score (60 dB) with a positive predictive value of 93%. CONCLUSIONS: Reduction in voice intensity is indicative of a higher risk of swallowing dysfunction. Thus, an instrumental voice analysis seems to be a non-invasive, lowcost, easy-to-use tool to identify people with PD in need of an assessment to allow for timely swallowing management and reduction of complications caused by dysphagia.

Sensitivity of Phonation Onset Pressure to Vocal Fold Stiffness Distribution.

Phonation onset is characterized by the unstable growth of vocal fold (VF) vibrations that ultimately results in self-sustained oscillation and the production of modal voice. Motivated by histological studies, much research has focused on the role of the layered structure of the vocal folds in influencing phonation onset, wherein the outer "cover" layer is relatively soft and the inner "body" layer is relatively stiff. Recent research, however, suggests that the body-cover (BC) structure over-simplifies actual stiffness distributions by neglecting important spatial variations, such as inferior-superior (IS) and anterior-posterior gradients and smooth transitions in stiffness from one histological layer to another. Herein, we explore sensitivity of phonation onset to stiffness gradients and smoothness. By assuming no a priori stiffness distribution and considering a second-order Taylor series sensitivity analysis of phonation onset pressure with respect to stiffness, we find two general smooth stiffness distributions most strongly influence onset pressure: a smooth stiffness containing aspects of BC differences and IS gradients in the cover, which plays a role in minimizing onset pressure, and uniform increases in stiffness, which raise onset pressure and frequency. While the smooth stiffness change contains aspects qualitatively similar to layered BC distributions used in computational studies, smooth transitions in stiffness result in higher sensitivity of onset pressure than discrete layering. These two general stiffness distributions also provide a simple, low-dimensional, interpretation of how complex variations in VF stiffness affect onset pressure, enabling refined exploration of the effects of stiffness distributions on phonation onset.

Association of perioperative oral swallowing function with post-esophagectomy outcomes and nutritional statuses in patients with esophageal cancer.

Dysphagia after esophagectomy is a serious complication; however, no method has been established to accurately assess swallowing function. We evaluated the association of swallowing function tests with patients' post-esophagectomy complications and nutritional statuses. We retrospectively reviewed the data of 95 patients with esophageal cancer who underwent esophagectomy between 2016 and 2021. We performed perioperative swallowing function tests, including the repetitive saliva swallowing test (RSST), maximum phonation time (MPT), and laryngeal elevation (LE). Patients with recurrent laryngeal nerve palsy (RLNP) and respiratory complications (RC) had significantly lower postoperative RSST scores than patients without them; the scores in patients with or without anastomotic leakage (AL) were similar. Postoperative MPT in patients with RLNP was shorter than that in patients without RLNP; however, it was similar to that in patients with or without AL and RC. LE was not associated with any complications. Patients with an RSST score ≤2 at 2 weeks post-esophagectomy had significant weight loss at 1, 6, and 12 months postoperatively compared with patients with an RSST score ≥3. The proportion of patients with severe weight loss (≥20% weight loss) within 1 year of esophagectomy was significantly greater in patients with RSST scores ≤2 than in those with RSST scores ≥3. Multivariate analysis showed that an RSST score ≤2 was the only predictor of severe post-esophagectomy weight loss. RSST scoring is a simple tool for evaluating post-esophagectomy swallowing function. A lower RSST score is associated with postoperative RLNP, RC, and poor nutritional status.

Wearable Sensor-Based Assessments for Remotely Screening Early-Stage Parkinson's Disease.

Prevalence estimates of Parkinson's disease (PD)-the fastest-growing neurodegenerative disease-are generally underestimated due to issues surrounding diagnostic accuracy, symptomatic undiagnosed cases, suboptimal prodromal monitoring, and limited screening access. Remotely monitored wearable devices and sensors provide precise, objective, and frequent measures of motor and non-motor symptoms. Here, we used consumer-grade wearable device and sensor data from the WATCH-PD study to develop a PD screening tool aimed at eliminating the gap between patient symptoms and diagnosis. Early-stage PD patients (n = 82) and age-matched comparison participants (n = 50) completed a multidomain assessment battery during a one-year longitudinal multicenter study. Using disease- and behavior-relevant feature engineering and multivariate machine learning modeling of early-stage PD status, we developed a highly accurate (92.3%), sensitive (90.0%), and specific (100%) random forest classification model (AUC = 0.92) that performed well across environmental and platform contexts. These findings provide robust support for further exploration of consumer-grade wearable devices and sensors for global population-wide PD screening and surveillance.

Effect of physical frailty on maximum phonation time in community-dwelling older individuals who visited a neurology outpatient clinic.

BACKGROUND: Maximum phonation time (MPT) is used to assess speech and other oral rehabilitation-related issues. Various factors contribute to MPT decline in older individuals. Although the impact of physical frailty on MPT has been suggested, this has not been conclusively determined. OBJECTIVE: To examine the relationship between MPT and physical frailty in community-dwelling individuals aged ≥60 years who were independently mobile. MPT-associated factors were investigated. METHODS: This cross-sectional study analysed the clinical data of 122 patients (age [interquartile range]: 80.0 [74.0-83.0] years) without dementia who visited a neurology department between 1 February 2021 and 31 January 2023. Investigated factors included age, sex, weight, height, body mass index, smoking history, grip strength, functional independence measure, vital capacity, oral diadochokinesis, MPT and the Japanese Cardiovascular Health Study score. Physical frailty was assessed based on the total score from five items (weight loss, weakness, exhaustion, slowness and low physical activity). The relationship between MPT and physical frailty was examined using Spearman's rank correlation coefficient and hierarchical multiple regression analysis. RESULTS: The MPT was negatively correlated with age (r = -0.347, p < .01) and physical frailty (r = -0.681, p < .01) and positively correlated with vital capacity (r = 0.474, p < .01) and height (r = 0.248, p < .01). The hierarchical multiple regression analysis, conducted with MPT as the dependent variable, demonstrated that physical frailty (ß = -.59, 95% confidence interval: -0.74 to 0.43, p < .001) had a strong influence on MPT. CONCLUSION: In older individuals, MPT is associated with physical frailty. When assessing MPT in clinical settings, it is advisable to perform a concurrent assessment of physical frailty.

Preferential use of full glottal stops in vowel-initial glottalization in child speech: Evidence from novel words.

Vowel-initial glottalization constitutes a cue to prosodic prominence, realized on a strength continuum from creaky phonation to complete glottal stops. While there is considerable research on children's early utilization of acoustic cues for stress marking, less is understood about the specific implementation of vowel-initial glottalization in American English. Eight sequences of function + novel words were elicited from groups of 5-to-8-year-olds, 8-to-11-year-olds, and adults. Children exhibit a similar rate of prevocalic glottalization to adults but differ in its phonetic implementation, producing a higher rate of glottal stops compared to creaky phonation with respect to adults.

Immediate Effects of Semi-Occluded Vocal Tract Exercises on Acoustic, Auditory-Perceptual, and Self-Perceptual Measures of Voice Production.

INTRODUCTION: This study examined the immediate acoustic, auditory-perceptual, and self-perceptual effects of two semi-occluded vocal tract exercises (SOVTs): straw phonation and straw phonation into a cup of water, delivered in a remote setting. METHOD: Thirty-six participants (19 females and 17 males) completed a baseline battery of acoustic recordings, followed by one of two SOVTs, and an identical post-task battery. The procedure repeated itself to include the other SOVT. Participants were also asked to rate their self-perceived vocal effort and quality following each condition. Recordings were presented to three expert listeners for completion of auditory-perceptual analysis. RESULTS: Acoustically, a significant decrease in shimmer was noted following straw phonation. Auditory-perceptual analysis revealed a significant increase in the perception of strain following straw phonation into a cup of water. While no significant differences were found between SOVT tasks in self-perception of vocal effort, a significant increase in self-perception of vocal loudness was reported following straw phonation into a cup of water. CONCLUSION: SOVTs have a varied, yet significant short-term impact across acoustic, auditory-perceptual, and self-perceptual measures of voice production. Straw phonation provided consistently significant acoustic results, with nearly every variable improving to some degree. Results also support the notion that shimmer is an acoustic measure that is particularly susceptible to change following modest manipulation. These results, in addition to the auditory-perceptual and self-perceptual findings, have a direct impact on how SOVTs are being used clinically and may generalize to inform the way voice metrics are collected and analyzed.

Changes in and clinical utility of maximum phonation time and repetitive saliva swallowing test scores after esophagectomy.

BACKGROUND: Postoperative pneumonia in patients with esophageal cancer occurs due to swallowing dysfunction and aspiration. Recently, maximum phonation time (MPT) assessment and repetitive saliva swallowing test (RSST) have been focused on as swallowing function assessment methods that can identify patients as high risk for pneumonia. We aimed to evaluate the clinical utility of MPT assessment and RSST in patients undergoing oncological esophagectomy. METHODS: In total, 47 consecutive patients who underwent esophagectomy for esophageal cancer between August 2020 and July 2023 were eligible. The perioperative changes in MPTs and RSST scores were examined. In addition, univariate and multivariate analyses were performed to identify the predictive factors of postoperative pneumonia. RESULTS: The median MPTs before surgery and on postoperative days (PODs) 3, 6, and 10 were 18.4, 7.2, 10.6, and 12.4 s, respectively; postoperative MPTs were significantly lower than preoperative MPT. In addition, the MPT of POD 6 was significantly longer than that of POD 3 (P < 0.05). Meanwhile, there were no significant changes in perioperative RSST scores. Overall, 8 of 47 patients (17.0%) developed pneumonia postoperatively. A short MPT on POD 6 was one of the independent predictive factors for the incidence of postoperative pneumonia (odds ratio: 12.6, 95% confidence interval: 1.29-123, P = 0.03) in the multivariate analysis. CONCLUSIONS: The MPT significantly decreased after esophagectomy. However, the RSST score did not. The MPT on POD6 can be a predictor of postoperative pneumonia.

Singing more, singing harsher: occurrence of nonlinear phenomena in a primate' song.

Nonlinear phenomena (NLP) in animal vocalizations arise from irregularities in the oscillation of the vocal folds. Various non-mutually exclusive hypotheses have been put forward to explain the occurrence of NLP, from adaptive to physiological ones. Non-human primates often display NLP in their vocalizations, yet the communicative role of these features, if any, is still unclear. We here investigate the occurrence of NLP in the song of a singing primate, the indri (Indri indri), testing for the effect of sex, age, season, and duration of the vocal display on their emission. Our results show that NLP occurrence in indri depends on phonation, i.e., the cumulative duration of all the units emitted by an individual, and that NLP have higher probability to be emitted in the later stages of the song, probably due to the fatigue indris may experience while singing. Furthermore, NLP happen earlier in the vocal display of adult females than in that of the adult males, and this is probably due to the fact that fatigue occurs earlier in the former because of a greater contribution within the song. Our findings suggest, therefore, that indris may be subjected to physiological constraints during the singing process which may impair the production of harmonic sounds. However, indris may still benefit from emitting NLP by strengthening the loudness of their signals for better advertising their presence to the neighboring conspecific groups.

Maximum phonation time: an independent predictor of late-onset pneumonia after esophageal cancer surgery.

Dysphagia after esophagectomy is a major risk factor for aspiration pneumonia, thus preoperative assessment of swallowing function is important. The maximum phonation time (MPT) is a simple indicator of phonatory function and also correlates with muscle strength associated with swallowing. This study aimed to determine whether preoperative MPT can predict postoperative aspiration pneumonia. The study included 409 consecutive patients who underwent esophagectomy for esophageal cancer between 2017 and 2021. Pneumonia detected by routine computed tomography on postoperative days 5-6 was defined as early-onset pneumonia, and pneumonia that developed later (most often aspiration pneumonia) was defined as late-onset pneumonia. The correlation between late-onset pneumonia and preoperative MPT was investigated. Patients were classified into short MPT (<15 seconds for males and <10 seconds for females, n = 156) and normal MPT groups (≥15 seconds for males and ≥10 seconds for females, n = 253). The short MPT group was significantly older, had a lower serum albumin level and vital capacity, and had a significantly higher incidence of late-onset pneumonia (18.6 vs. 6.7%, P < 0.001). Multivariate analysis showed that short MPT was an independent risk factor for late-onset pneumonia (odds ratio: 2.26, P = 0.026). The incidence of late-onset pneumonia was significantly higher in the short MPT group (15.6 vs. 4.7%, P = 0.004), even after propensity score matching adjusted for clinical characteristics. MPT is a useful predictor for late-onset pneumonia after esophagectomy.

Scoping review of the relationship between xerostomia and voice quality.

PURPOSE: This scoping review aims to synthesize all of the currently available information on how xerostomia correlates with vocal function and the mechanisms that underpin it. METHODS: Our scoping review used PubMed, Scopus, Embase, and Web of Science databases to review articles published between January 1999 and July 2022 in accordance with the PRISMA-ScR guidelines. In addition to the academic databases, we also conducted a manual search of Google Scholar. Further investigation was conducted on studies that examined the relationship between xerostomia and vocal function. RESULTS: Of the 682 initially identified articles, 21 met our inclusion criteria. Among the included studies, two articles (n = 2) revealed the mechanistic relationship between xerostomia and vocal function. Most studies (n = 12) focused on xerostomia secondary to other underlying conditions or treatments, among which radiotherapy and Sjögren's syndrome were commonly investigated. Seven studies (n = 7) provided details about common vocal parameters measured in studies of xerostomia and the voice. CONCLUSION: The literature currently lacks publications regarding the relationship between xerostomia and vocal function. Most of the studies included in this review were about xerostomia secondary to other conditions or medical treatments. Therefore, the impacts on the voice that were observed were very multifaceted and the role of xerostomia alone in phonation could not be ascertained. Nevertheless, it is clear that dryness in the mouth plays some role in vocal function and further research should focus on clarifying and finding the underlying mechanism behind this relationship by incorporating high-speed imaging and cepstral peak prominence analyses.

Immediate effects of straw phonation in air or water on the laryngeal function and configuration of female speech-language pathology students visualised with strobovideolaryngoscopy: A randomised controlled trial.

BACKGROUND: A promising way to obtain vocal economy and efficiency is by semi-occluding the vocal tract while phonating. Current knowledge about the immediate effects of semi-occluded vocal tract (SOVT) phonation on the laryngeal function and configuration is based mainly on computer modelling or excised larynges studies. In in vivo SOVT studies, electroglottography (EGG) has been the most commonly used laryngeal outcome, showing contradictory results between studies. Therefore, exploring these aspects by direct visualisation of the human larynx during SOVT phonation using strobovideolaryngoscopy (SVL) is needed. AIMS: The aim of this study was to investigate and compare the immediate effects of straw phonation (SP) in air, SP in 2 cm water, and SP in 5 cm water (with stirring straws), on the laryngeal function and configuration of a homogeneous group of vocally healthy female speech-language pathology students, visualised with flexible SVL. METHODS & PROCEDURE: A randomised controlled trial was used. Fifty-two female speech-language pathology students (mean age: 18.7 years, SD: 0.6) were assigned randomly to one of three experimental groups or a control group: (1) SP in air, (2) SP in 2 cm water, (3) SP in 5 cm water or (4) [u] phonation with similar soft onset and slightly pursed lips as in SP but without a straw (control group). The participants underwent flexible SVL during habitual [u] phonation, followed by the specific SOVT exercise of their group assignment. All video samples were evaluated randomly and blindly by two experienced investigators using the Voice-Vibratory Assessment with Laryngeal Imaging (VALI) rating form, first independently and then by consensus. OUTCOME & RESULTS: Compared to habitual phonation, the vibrational amplitude decreased during SP in 5 cm water and SP in 2 cm water, being more prominent in the first, more flow-resistant exercise. The mucosal wave also decreased during SP in 5 cm water. The anteroposterior (AP) supraglottic compression similarly increased during SP in air, SP in 2 cm water, and SP in 5 cm water. Further, a rise in mediolateral (ML) compression and a decrease in phase symmetry and regularity were found during SP in 2 cm water. A similar decrease in regularity was observed during SP in 5 cm water. CONCLUSIONS & IMPLICATIONS: Both SP in air and SP in water cause positive immediate laryngeal effects for voice training opportunities. More AP supraglottic activity found during each SP exercise might indicate epilarynx narrowing, an economic phenomenon associated with SOVT. Immersing the straw in water additionally diminished the vibrational amplitude, lowering vocal fold impact stress and risk for phonotrauma during the exercise. The decreased regularity of the vibrational cycles during SP in water might be due to the varying back pressure created by the water bubbling. The impact of SP in water on ML supraglottic compression needs further investigation. WHAT THIS PAPER ADDS: What is already known on the subject A promising way to obtain vocal economy and efficiency is by semi-occluding the vocal tract while phonating. Current knowledge about the immediate effects of semi-occluded vocal tract (SOVT) phonation on the laryngeal function and configuration is based mainly on computer modelling or excised larynges studies. In in vivo SOVT studies, electroglottography (EGG) has been the most commonly used laryngeal outcome, showing contradictory results between studies. Therefore, exploring these aspects by direct visualisation of the human larynx during SOVT phonation using strobovideolaryngoscopy (SVL) is needed. What this paper adds to existing knowledge Group results of the current study generally support earlier computer modelling and in vivo studies, strengthening the current SOVT knowledge. Both SP in air and SP in water cause positive immediate laryngeal effects for voice training opportunities. More anteroposterior (AP) supraglottic activity found during each SP exercise might indicate epilarynx narrowing, an economic phenomenon associated with SOVT. Immersing the straw in water additionally diminished the vibrational amplitude, lowering vocal fold impact stress and risk for phonotrauma during the exercise. The decreased regularity of the vibrational cycles during SP in water might be due to the varying back pressure created by the water bubbling. The impact of SP in water on ML supraglottic compression needs further investigation. What are the potential or actual clinical implications of this work? Current results support that both SP in air and SP in water can be useful exercises in voice training. SP in water has shown the additional gain of lowering the vibrational amplitude during the exercise, hence supporting its appropriateness for vocal warm-ups by minimising vocal fold impact stress and the risk of phonotrauma. In the future, large-scale randomised controlled trials in other subgroups of voice users, including dysphonic patients, are needed to support evidence-based practice. SVL can facilitate the search for individualised training and therapy approaches.

The maximum phonation time as marker for voice treatment efficacy: A network meta-analysis.

PURPOSE: There is a diversity in treatment approaches for voice therapy in which aerodynamic treatment effects between the approaches are lacking. The evidence of voice treatments on the maximum phonation time (MPT) was quantified using the statistical approach of a network meta-analysis (NMA). DATA SOURCES: Three databases and manual search from inception to November 2021 were evaluated. STUDY SELECTION: Studies were considered which were reports of randomised controlled/clinical trials (RCT) evaluating the efficacy of a specific voice therapy treatment using MPT as an outcome measure in adult participants with voice disorders. Studies were excluded if participants had been diagnosed with neurological-motor-speech disorders or who were vocally healthy. Furthermore, no medical, pharmacological, or technical instrumental treatments were used. DATA EXTRACTION AND SYNTHESIS: Preferred Reporting Items for systematic reviews and meta-analyses extension statement guidelines were followed. Two reviewers independently screened citations, extracted data, and assessed risk of bias using PEDro scale. Random effects model was used for meta-analysis. RESULTS: We identified finally 12 RCT studies (treatment groups n = 285, and control group without an intervention n = 62). Eight interventions were evaluated. The only effective intervention with a significant effect was vocal function exercises (VFE) (mean pre-post difference 6.16 s, 95% confidence interval, 1.18-11.13 s). CONCLUSIONS AND RELEVANCE: VFE effectively improved MPT from pre- to post-treatment in comparison with other voice interventions which were identified in the present NMA. Further high-quality intervention studies with large samples sizes, multidimensional measures, and homogeneous groups of dysphonia are needed to support evidence-based practice in laryngology.

Word-level prosodic and metrical influences on Hawaiian glottal stop realization.

Previous research on the phonetic realization of Hawaiian glottal stops has shown that it can be produced several ways, including with creaky voice, full closure, or modal voice. This study investigates whether the realization is conditioned by word-level prosodic or metrical factors, which would be consistent with research demonstrating that segmental distribution and phonetic realization can be sensitive to word-internal structure. At the same time, it has also been shown that prosodic prominence, such as syllable stress, can affect phonetic realization. Data come from the 1970s-80s radio program Ka Leo Hawai'i. Using Parker Jones' (Parker Jones, Oiwi. 2010. A computational phonology and morphology of Hawaiian. University of Oxford DPhil. thesis) computational prosodic grammar, words were parsed and glottal stops were automatically coded for word position, syllable stress, and prosodic word position. The frequency of the word containing the glottal stop was also calculated. Results show that full glottal closures are more likely at the beginning of a prosodic word, especially in word-medial position. Glottal stops with full closure in lexical word initial position are more likely in lower frequency words. The findings for Hawaiian glottal stop suggest that prosodic prominence does not condition a stronger realization, but rather, the role of the prosodic word is similar to other languages exhibiting phonetic cues to word-level prosodic structure.

Deriving Vocal Fold Oscillation Information from Recorded Voice Signals Using Models of Phonation.

During phonation, the vocal folds exhibit a self-sustained oscillatory motion, which is influenced by the physical properties of the speaker's vocal folds and driven by the balance of bio-mechanical and aerodynamic forces across the glottis. Subtle changes in the speaker's physical state can affect voice production and alter these oscillatory patterns. Measuring these can be valuable in developing computational tools that analyze voice to infer the speaker's state. Traditionally, vocal fold oscillations (VFOs) are measured directly using physical devices in clinical settings. In this paper, we propose a novel analysis-by-synthesis approach that allows us to infer the VFOs directly from recorded speech signals on an individualized, speaker-by-speaker basis. The approach, called the ADLES-VFT algorithm, is proposed in the context of a joint model that combines a phonation model (with a glottal flow waveform as the output) and a vocal tract acoustic wave propagation model such that the output of the joint model is an estimated waveform. The ADLES-VFT algorithm is a forward-backward algorithm which minimizes the error between the recorded waveform and the output of this joint model to estimate its parameters. Once estimated, these parameter values are used in conjunction with a phonation model to obtain its solutions. Since the parameters correlate with the physical properties of the vocal folds of the speaker, model solutions obtained using them represent the individualized VFOs for each speaker. The approach is flexible and can be applied to various phonation models. In addition to presenting the methodology, we show how the VFOs can be quantified from a dynamical systems perspective for classification purposes. Mathematical derivations are provided in an appendix for better readability.

A Contemporary Review of Clinical Factors Involved in Speech-Perspectives from a Prosthodontist Point of View.

Background and Objectives: Learning to speak properly requires a fully formed brain, good eyesight, and a functioning auditory system. Defective phonation is the outcome of a failure in the development of any of the systems or components involved in speech production. Dentures with strong phonetic skills can be fabricated with the help of a dentist who has a firm grasp of speech production and phonetic characteristics. Every dentist strives to perfect their craft by perfecting the balance between the technical, cosmetic, and acoustic aspects of dentistry, or "phonetics". The ideal prosthesis for a patient is one that not only sounds good but also functions well mechanically and aesthetically. Words are spoken by using articulators that alter their size and form. Conclusions: Therefore, a prosthesis should be made in such a way that it does not interfere with the ability to communicate. As a result, a prosthodontist has to have a solid grasp of how speech is made and the numerous parts that go into it.

Preoperative maximum phonation time as a predictor of pneumonia in patients undergoing esophagectomy.

PURPOSE: Esophagectomy is a highly invasive procedure, associated with several postoperative complications including pneumonia, anastomotic leakage, and sepsis, which may result in multiorgan failure. Pneumonia is considered a major predictor of poor long-term prognosis, so its prevention is important for patients undergoing surgery for esophageal cancer. METHODS: The subjects of this study were 137 patients who underwent esophagectomy at Keio University Hospital, Tokyo, Japan, between January, 2012 and December, 2016. Patients who underwent R0 or R1 resection or esophagectomy with organ excision were included. Patients who underwent salvage surgery or resection of recurrent laryngeal nerve, and those with preoperative recurrent laryngeal nerve palsy, were excluded. We investigated the effect of the maximum phonation time on the development of postoperative pneumonia. RESULTS: Pneumonia developed more frequently in patients with a long operative time, clinically left recurrent nerve lymph node metastasis, and a short preoperative maximum phonation time (p = 0.074, 0.046, and 0.080, respectively). Pneumonia was also more common in men with an abnormal maximum phonation time (p = 0.010). CONCLUSIONS: The maximum phonation time is a significant predictor of postoperative pneumonia after esophagectomy in men.

Does the wearing of masks change voice and speech parameters?

PURPOSE: The authors aim to review available reports on the potential effects of masks on voice and speech parameters. METHODS: A literature search was conducted using MEDLINE and Google Scholar databases through July 2021. Several targeted populations, mask scenarios and methodologies were approached. The assessed voice parameters were divided into self-reported, acoustic and aerodynamic. RESULTS: It was observed that the wearing of a face mask has been shown to induce several changes in voice parameters: (1) self-reported-significantly increased vocal effort and fatigue, increased vocal tract discomfort and increased values of voice handicap index (VHI) were observed; (2) acoustics-increased voice intensity, altered formants frequency (F2 and F3) with no changes in fundamental frequency, increased harmonics-to-noise ratio (HNR) and increased mean spectral values in high-frequency levels (1000-8000 Hz), especially with KN95 mask; (3) aerodynamics-maximum phonatory time was assessed in only two reports, and showed no alterations. CONCLUSION: Despite the different populations, mask-type scenarios and methodologies described by each study, the results of this review outline the significant changes in voice characteristics with the use of face masks. Wearing a mask shows to increase the perception of vocal effort and an alteration of the vocal tract length and speech articulatory movements, leading to spectral sound changes, impaired communication and perception. Studies analyzing the effect of masks on voice aerodynamics are lacking. Further research is required to study the long-term effects of face masks on the potential development of voice pathology.

Multi-dimensional investigation of the clinical effectiveness and prognostic factors of voice therapy for benign voice disorders.

BACKGROUND/PURPOSE: Voice therapy is frequently recommended as the first-line treatment for benign voice disorders. This study investigated the clinical effectiveness of voice therapy and the prognostic factors of treatment outcomes. METHODS: We recruited 103 consecutive patients with voice disorders, namely vocal nodules, polyps, and muscle tension dysphonia (MTD), from September 2014 to July 2016. All the patients received voice therapy as the primary treatment. Treatment outcomes were evaluated using auditory perceptual evaluation, acoustic analysis, maximum phonation time, and 10-item voice handicap index (VHI-10). Clinical effectiveness of voice therapy was defined by either 1) a posttreatment VHI-10 score ≤ 10 points or 2) decline of VHI-10 ≥ 4 points. RESULTS: After voice therapy, VHI-10 and perceptual rating of voice quality improved significantly (p < 0.05) in the three disease categories. In patients with nodules, all the outcome parameters improved significantly (p < 0.05). Patients with good adherence to voice therapy (attending more than four sessions) had a significantly higher effectiveness than those with poor adherence (87% vs. 64%, p < 0.05). Patients with high occupational vocal demand also demonstrated a better effectiveness than those with routine vocal demand (90% vs. 70%, p < 0.05). Subsequent multivariate analyses revealed that adherence and vocal demand were independently and significantly correlated with clinical effectiveness (p = 0.03). CONCLUSION: Voice therapy is effective for patients with vocal nodules, polyps, and MTD. Adherence to voice therapy and occupational vocal demand are significant prognostic factors for treatment outcomes.

Transphonologization of onset voicing: revisiting Northern and Eastern Kmhmu'.

Phonation and vowel quality are often thought to play a vital role at the initial stage of tonogenesis. This paper investigates the production of voicing and tones in a tonal Northern Kmhmu' dialect spoken in Nan Province, Thailand, and a non-tonal Eastern Kmhmu' dialect spoken in Vientiane, Laos, from both acoustic and electroglottographic perspectives. Large and consistent VOT differences between voiced and voiceless stops are preserved in Eastern Kmhmu', but are not found in Northern Kmhmu', consistent with previous reports. With respect to pitch, f0 is clearly a secondary property of the voicing contrast in Eastern Kmhmu', but unquestionably the primary contrastive property in Northern Kmhmu'. Crucially, no evidence is found to suggest that either phonation type or formant differences act as significant cues to voicing in Eastern Kmhmu' or tones in Northern Kmhmu'. These results suggests that voicing contrasts can also be transphonologized directly into f0-based contrasts, skipping a registral stage based primarily on phonation and/or vowel quality.