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Configura??o das pregas vestibulares em laringes de pacientes com nódulo vocal
Tuma, Juliane;Camponês do Brasil, Osíris Oliveira;Pontes, Paulo Augusto de Lima;Yasaki, Reinaldo Kasuo;
Revista Brasileira de Otorrinolaringologia , 2005, DOI: 10.1590/S0034-72992005000500006
Abstract: vocal nodules are among the most common laryngopathies that cause vocal functional disorders. the voice production mechanism is complex and demand interaction of different systems of the human body. the physiological role of the vocal folds as the glottic sound source is evident, however, there is no consensus regarding the vestibular folds' participation/influence in phonation. aim: to verify if there is difference in the bidimensional configuration of the vestibular folds between two distinct groups of women, one with the diagnosis of vocal nodules and the other without vocal complaints and vocal fold lesions. study design: clinical with transversal cohort. material and method: ninety-six laryngeal images were evaluated, 48 from individuals without vocal complaints and 48 from patients with the diagnosis of vocal nodules. angles were obtained and bilaterally measured in single frames of the vestibular folds during sustained phonation and those structures were morphologically classified as concave, linear or convex. results: among the 96 vestibular folds evaluated in each group, there was predominance of the concave form, followed by the linear and the convex ones. in the control group, there was a single convex vestibular fold, 27 were linear and 68 were concave folds. in the group of vocal nodules, 8 were convex, 15 were linear and 73 were concave folds. however, the differences among groups were not statistically significant as well as those among the angles, whose average measures were proven quite similar. conclusion: in the female gender, the vestibular folds presented similar behavior regarding the morphology in both patients with vocal nodules and women without vocal complaints.
The effects of the false vocal fold gaps on intralaryngeal pressure distributions and their effects on phonation
Sheng Li,MingXi Wan,SuPin Wang
Science China Life Sciences , 2008, DOI: 10.1007/s11427-008-0128-3
Abstract: Human phonation does not merely depend on the vibration of the vocal folds. Research by clinical and computer simulations has demonstrated that the false vocal fold (FVF) is an important laryngeal constriction that plays a vital role during human voice production. This study explored the effects of the FVF gaps using both the three-dimensional Plexiglas model and the numerical computation methods. Twelve FVF gaps (ranging from 0.02 to 2.06 cm) were used in this study at three glottal angles (uniform and convergent/divergent 40°), two minimal glottal diameters (D g) (0.04 cm and 0.06 cm) separately, and the constant subglottal pressure (8 cm H2O). The results suggested that (1) the intralaryngeal pressure was the lowest and the flow was the highest (least flow resistance) when the FVF gap was 1.5–2 times greater than D g; (2) the divergent glottal angle gave lower pressure and greater flow than the convergent and uniform glottal angle as there were no FVF conditions; (3) the presence of the FVF decreased the effects of the glottal angle to a certain extent; and more importantly, (4) the presence of the FVF also moved the separation points downstream, straightened the glottal jet for a longer distance, decreased the overall laryngeal resistance, and reduced the energy dissipation, suggesting the significance of FVF in efficient voice production. These results may be incorporated in the phonatory models (physical or computational) for better understanding of vocal mechanics. The results might also be helpful in exploring the surgical and rehabilitative intervention of related voice problems.
Les es de borda de pregas vocais e tempos máximos de fona o Vocal folds edge lesions and maximum phonation times  [cached]
Bárbara Costa Beber,Carla Aparecida Cielo,Márcia Amaral Siqueira
Revista CEFAC , 2009,
Abstract: OBJETIVO: comparar o diagnóstico otorrinolaringológico de les o de borda de prega vocal e seus Tempos Máximos de Fona o em adultos e crian as de ambos os sexos; verificar a frequência dos tipos de TMF (reduzido, normal ou aumentado) nas patologias de borda de pregas vocais e a frequência dessas patologias em indivíduos com pregas vocais maduras (adultos) e imaturas (crian as), em ambos os sexos. MéTODOS: resgate no banco de dados de pacientes com queixas de voz, atendidos em um servi o de atendimento fonoaudiológico universitário, com diagnóstico médico de patologia de borda de prega vocal. Entre os 152 registros apresentados pelo banco de dados, 54 passaram pelos critérios de inclus o, sendo oito casos de cisto vocal e 46 de nódulo vocal. RESULTADOS: os nódulos vocais foram as les es mais frequentes em adultos e crian as, com maior parcela em mulheres adultas e crian as do sexo masculino. Os cistos vocais ocorreram em maior parcela no sexo feminino tanto em crian as como em adultos. Houve redu o nos tempos máximos de fona o de crian as de ambos os sexos e de mulheres adultas. CONCLUS O: as les es de borda de pregas vocais, por dificultarem o adequado fechamento glótico, tendem a causar redu o nos valores de Tempos Máximos de Fona o. PURPOSE: to compare the otorhinolaryngologic diagnosis of vocal folds edge lesions and their Maximum Phonation Times in adults and children of both genders; to check the frequency of the Maximum Phonation Times types (reduced, normal or increased) in the pathologies of vocal folds edge and the frequency of these pathologies in individuals with mature vocal fold edge (adults) and immature vocal fold edge (children) in both genders. METHODS: to recover the database of the patients that have complained about voice. They have been attended in a phonological university service office, with a medical diagnosis of the edge pathology of vocal fold. Among the 152 records displayed by the database, 54 have been passed for the inclusion criteria, being 8 cases from cysts of vocal fold and 46 from vocal fold nodules. RESULTS: the vocal fold nodules have showed the lesions with more frequency in adults and children, with higher portion in adult women and male gender children. The cysts of vocal folds have occurred in a higher portion in female gender both in children as well as in adults. There was a decrease in Maximum Phonation Times of children of both gender and of adults women. CONCLUSION: as the vocal fold edge lesions difficult the appropriate glottal closing, they tend to cause a decrease in the Maximum Phonation Times valu
Computational aeroacoustics of human phonation  [cached]
?idlof P.,Z?rner S.
EPJ Web of Conferences , 2013, DOI: 10.1051/epjconf/20134501085
Abstract: The current paper presents a CFD model of flow past vibrating vocal folds coupled to an acoustic solver, which calculates the sound sources from the flow field in a hybrid approach. The CFD model is based on the numerical solution of 3D Navier-Stokes equations on a time-dependent domain, solved by cell-centered finite volume method. To capture the fine turbulent scales important for the acoustic source calculations, the equations are discretized and solved on large computational meshes up to 3.2M elements. The CFD simulations were run in parallel using domain decomposition method and OpenMPI implementationof the MPI standard. Aeroacoustic simulations are calculated in a separate step by Lighthill’s acoustic analogy, which determines the acoustic sources based on the fluid field. This is done with the research code CFS++ which employs the finite element method (FEM).
The effects of the false vocal fold gaps on intralaryngeal pressure distributions and their effects on phonation

Sheng Li,MingXi Wan,SuPin Wang,

中国科学C辑(英文版) , 2008,
Abstract: Human phonation does not merely depend on the vibration of the vocal folds. Research by clinical and computer simulations has demonstrated that the false vocal fold (FVF) is an important laryngeal constriction that plays a vital role during human voice production. This study explored the effects of the FVF gaps using both the three-dimensional Plexiglas model and the numerical computation methods. Twelve FVF gaps (ranging from 0.02 to 2.06 cm) were used in this study at three glottal angles (uniform and convergent/divergent 40°), two minimal glottal diameters (D g) (0.04 cm and 0.06 cm) separately, and the constant subglottal pressure (8 cm H2O). The results suggested that (1) the intralaryngeal pressure was the lowest and the flow was the highest (least flow resistance) when the FVF gap was 1.5–2 times greater than D g; (2) the divergent glottal angle gave lower pressure and greater flow than the convergent and uniform glottal angle as there were no FVF conditions; (3) the presence of the FVF decreased the effects of the glottal angle to a certain extent; and more importantly, (4) the presence of the FVF also moved the separation points downstream, straightened the glottal jet for a longer distance, decreased the overall laryngeal resistance, and reduced the energy dissipation, suggesting the significance of FVF in efficient voice production. These results may be incorporated in the phonatory models (physical or computational) for better understanding of vocal mechanics. The results might also be helpful in exploring the surgical and rehabilitative intervention of related voice problems. Supported by the National Natural Science Foundation of China (Grant No. 30770544), and the National Postdoctoral Science Foundation of China (Grant No. 200704211131)
Modal locking between vocal fold and vocal tract oscillations: Simulations in time domain  [PDF]
Atte Aalto,Tiina Murtola,Jarmo Malinen,Daniel Aalto,Martti Vainio
Physics , 2015,
Abstract: It is well known that during voiced speech, the human vocal folds interact with the vocal tract acoustics. The resulting source-filter coupling has been observed using mathematical and physical models as well as in in vivo phonation. We propose a computational time-domain model of the full speech apparatus that, in particular, contains a feedback mechanism from the vocal tract acoustics to the vocal fold oscillations. It is based on numerical solution of ordinary and partial differential equations defined on vocal tract geometries that have been obtained by Magnetic Resonance Imaging. The model is used to simulate rising and falling pitch glides of [a, i] in the fundamental frequency (f_0) interval [180 Hz, 360 Hz]. The interval contains the first formant F1 of [i] as well as the subformants F1/4 and F1/3 of [a]. The simulations reveal a locking pattern of the f_0-trajectory at F1 of [i] in falling and rising glides. The subformants of [a] produce perturbations in the waveforms of glottal signals but no locking. All these observations from the model behaviour are consistent and robust within a wide range of feasible model parameter values and under exclusion of secondary model components. The simulation results suggest that the leading source of discrepancy between the model and true speech biophysics in vowels at frequencies under 4kHz is due to simplified flow modelling. The characteristics of the simulated locking pattern can be used for developing a high-resolution statistical instrument for detection of the same pattern in experimental material.
Tempos máximos de fona o e características vocais acústicas de mulheres com nódulos vocais Maximum phonation time and vocal acoustic characteristics for women with vocal fold nodule  [cached]
Carla Aparecida Cielo,Sabrina Schützenhofer Lasch,Shanna Lara Miglioranzi,Giseane Conterno
Revista CEFAC , 2011,
Abstract: OBJETIVO: descrever os tempos máximos de fona o (TMF) e características vocais acústicas de mulheres adultas jovens com nódulos vocais. MéTODOS: coleta dos TMF das vogais /a/, /i/ e /u/; da rela o s/z e medidas acústicas da fonte glótica (Multi Dimensional Voice Program Advanced da Kay PENTAX) de 20 sujeitos do sexo feminino, com faixa etária entre 20 e 40 anos, dez com laudo otorrinolaringológico de nódulos vocais e dez com laudo de laringe normal. RESULTADOS: quanto aos TMF, o grupo sem nódulos (GSN) apresentou 90% dos resultados normais e 10% diminuídos, e o grupo com nódulos (GCN) apresentou 70% dos resultados normais e 30% diminuídos; na rela o s/z, todo o GSN apresentou resultados dentro dos padr es da normalidade e o GCN apresentou 70% de resultados normais e 30% aumentados; ambos os grupos apresentaram todas as medidas vocais acústicas dentro da normalidade, com exce o do GSN que apresentou vf0 aumentada. CONCLUS O: as mulheres jovens com nódulos vocais apresentaram medidas de TMF e de rela o s/z sem diferen as significativas em rela o às mesmas medidas de mulheres sem afec o laríngea. As medidas acústicas da fonte glótica foram semelhantes e dentro da normalidade para ambos os grupos, com exce o da medida do cociente de varia o de frequência fundamental (vf0) que foi elevada no GSN, sugerindo incoordena o penumofonoarticulatória. As medidas de TMF e da rela o s/z, mesmo sem diferen as significativas, pareceram mais sensíveis à presen a do predomínio aerodinamico dos nódulos vocais do que as medidas acústicas. PURPOSE: to describe maximum phonation time (MPT) and vocal acoustic characteristics for young adult women with vocal fold nodules. METHODS: collection of MPT of the vowels /a/, /i/ and /u/; s/z ratio and acoustic measures of the glottal source (Multi Dimensional Voice Program Advanced from Kay PENTAX) of 20 female subjects, aged between 20 and 40 year old, being ten with otorhinolaryngologic diagnosis of vocal fold nodules and ten with normal larynx diagnosis. RESULTS: regarding the MPT, the group with normal larynx (GNL) showed 90% of normal values and 10% reduced, while the group with nodules (GWN) showed 70% of normal values and 30% reduced; the s/z ratio showed results within normal patterns, for the whole GNL, while the GWN showed 70% of normal results and 30% increased; both the groups had all the vocal acoustic measures within normality range, except for the GNL which showed increased vf0. CONCLUSION: young women with vocal nodules showed MPT and s/z ratio measures with no significant differences in relation to the same
Disentangling the effects of phonation and articulation: Hemispheric asymmetries in the auditory N1m response of the human brain
Hannu Tiitinen, Anna M?kel?, Ville M?kinen, Patrick JC May, Paavo Alku
BMC Neuroscience , 2005, DOI: 10.1186/1471-2202-6-62
Abstract: The N1m responses for the six stimulus types displayed a considerable dynamic range of 115–135 ms, and were elicited faster (~10 ms) by the high-formant /a/ than by the low-formant /u/, indicating an effect of articulation. While excitation type had no effect on the latency of the right-hemispheric N1m, the left-hemispheric N1m elicited by the tonally excited /a/ was some 10 ms earlier than that elicited by the periodic and the aperiodic excitation. The amplitude of the N1m in both hemispheres was systematically stronger to stimulation with natural periodic excitation. Also, stimulus type had a marked (up to 7 mm) effect on the source location of the N1m, with periodic excitation resulting in more anterior sources than aperiodic and tonal excitation.The auditory brain areas of the two hemispheres exhibit differential tuning to natural speech signals, observable already in the passive recording condition. The variations in the latency and strength of the auditory N1m response can be traced back to the spectral structure of the stimuli. More specifically, the combined effects of the harmonic comb structure originating from the natural voice excitation caused by the fluctuating vocal folds and the location of the formant frequencies originating from the vocal tract leads to asymmetric behaviour of the left and right hemisphere.A voiced speech signal such as a vowel is created in the human sound production system through phonation and articulation [1]. In normal phonation, the vibrating vocal folds produce a periodic excitation, termed the glottal flow. Due to this inherent periodicity, the spectra of vowels produced by normal phonation are characterized by a harmonic comb structure, i.e., distribution of energy at the fundamental frequency (F0, ranging from 100 Hz in males up to 400 Hz in infants) and its harmonic integer multiples (2 × F0, 3 × F0, etc.) located regularly in frequency [2]. This comb structure is then locally weighted in frequency by the resonances caus
Análise vocal e laríngea na hipótese diagnóstica de nódulos e cistos
Barata, Lívia Fernandes;Madazio, Glaucya;Behlau, Mara;Brasil, Osíris do;
Revista da Sociedade Brasileira de Fonoaudiologia , 2010, DOI: 10.1590/S1516-80342010000300007
Abstract: purpose: to verify, using inspiratory phonation, whether visual and auditory-perceptual parameters correlate with the diagnostic hypothesis of nodules and cysts. methods: twenty one videolaryngostroboscopies of patients with suspected nodules (n=6) and cysts (n=15) were analyzed. subjects were 18 women and three men, with mean age of 35 years (13-68 years). visual and auditory data, obtained from expiratory and inspiratory phonation, were randomly presented, compared and registered in a specific protocol by a trained speech-language pathologist, to whom diagnostic hypotheses were omitted. results: in nodule cases, sustained vowel showed higher occurrence of vocal deviation (66.7%), when compared to speech (33.3%); sustained vowel had a breathy quality (100%) and speech was adapted (66.7%). in cyst cases, deviation was also more frequent during sustained vowel (46.7%) than during speech (40%); sustained vowel presented both roughness (40%) and breathiness (33.3%). all nodules were symmetric in location (100%), and most were also symmetric in size, in both types of phonation (66.7% and 75% respectively). cysts tended to be symmetric in location (75%), but asymmetric in size (100%). the vocal ligament was more visible in cysts (53.3% and 80%) than in nodules (33.3% and 66.7%), in expiratory and inspiratory phonation respectively, and this structure was more evident during inspiratory phonation. when visible in nodules, the vocal ligament was bilateral (100%). conclusion: inspiratory phonation revealed differential characteristics for nodules and cysts diagnoses; the auditory-perceptual evaluation added information to characterize both lesions.
Effects of Voice Therapy on Vocal Acoustic Characteristics in Patients With Vocal Cord Nodules
Mehri safari,Ali Ghorbani,Yunos Amiri Shavaki,Farzad Izadi
Audiology , 2011,
Abstract: Background and Aim: Vocal cord nodule is one of the voice disorders causes hoarseness and breathy voice. Voice therapy is one of the treatment approaches. We aimed to find out the effects of voice therapy on vocal acoustic characteristics in these patients.Methods: In this case series, five women with vocal nodule (14 to 45-year-old) participated in a 9-week voice therapy program developed by Boone. Vocal hygiene and voice practices were measured every day using a questionnaire. Moreover, structure and movements of vocal folds were examined using videolaryngostroboscope by a laryngologist before and after voice therapy to evaluate the effectiveness of program. For collecting voice samples we used sustained / / in comfortable loudness for all patients and data were analyzed using Speech Studio.Results: After voice therapy, fundamental frequency in four of five subjects were decreased but it was not significant (p=0.225). However, jitter in all of five subjects was significantly decreased (p=0.043). After voice therapy, shimmer in three of five subjects were decreased that was not significant (p=0.345).Conclusion: Voice therapy can be used for the remedy of acoustic vocal characteristics and elimination or contraction of vocal cord nodule.
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