INTRODUÇÃO: O grande desafio para o laringologista perante o quadro de paralisia unilateral do músculo cricotireoideo é fazer o diagnóstico do comprometimento desse músculo por meio da laringoscopia. Não existe consenso na literatura em relação aos achados vibratórios que possam servir como comprovação dessa condição. O objetivo desse estudo foi avaliar os efeitos da contração do músculo cricotireoideo sobre a vibração das pregas vocais usando a videolaringoscopia de alta velocidade e tentar encontrar um ou mais achados que pudessem ser utilizados como um sinal indicativo de paralisia unilateral do músculo cricotireoideo. MÉTODOS: Realizou-se um estudo experimental com 20 laringes excisadas de cadáveres humanos adultos masculinos. A vibração cordal foi produzida artificialmente com a passagem de ar comprimido através das pregas vocais. Cada laringe foi avaliada em três situações: contração bilateral do músculo cricotireoideo, contração unilateral do músculo cricotireoideo e ausência de contração de ambos os músculos cricotireoideos. Os seguintes parâmetros foram avaliados pela videolaringoscopia de alta velocidade: frequência fundamental, periodicidade da vibração, amplitude de vibração das pregas vocais e simetria de fase entre as pregas vocais. RESULTADOS: A diminuição da tensão longitudinal das pregas vocais decorrente da ausência de contração do músculo cricotireoideo unilateral e bilateral mostrou não alterar a periodicidade da vibração e a presença de assimetria de fase entre as pregas vocais, mas houve uma diminuição significativa da frequência fundamental (p < 0,001). Observou-se, também, um aumento da amplitude de vibração das pregas vocais direita e esquerda (p < 0,05), que apresentaram comportamento semelhante para esse parâmetro nas diferentes situações estudadas. CONCLUSÕES: A diminuição da tensão nas pregas vocais, causada pela ausência da contração do músculo cricotireoideo unilateral e bilateral, resultou em uma diminuição da frequência fundamental e em um aumento da amplitude de vibração. A presença de periodicidade em todas as laringes sugere que a videoestrobolaringoscopia, método usado mais frequentemente na prática clínica, possa ser um método adequado para avaliar pacientes com paralisia unilateral do músculo cricotireoideo. E, finalmente, os resultados sugerem que a paralisia unilateral do músculo cricotireoideo parece não ser capaz de produzir uma assimetria de tensão suficiente para induzir diferença de amplitude de vibração e de fase entre as pregas vocais e, desta forma, esses parâmetros não podem ser utilizados para fazer uma diferenciação segura dessa condição / INTRODUCTION: The great challenge for laryngologists dealing with cricothyroid muscle paralysis is to diagnose impaired cricothyroid muscle function using laryngoscopy. There is no consensus in the literature on the vibratory findings that can be used as a proof of this condition. The aim of this study was to evaluate the effects that cricothyroid muscle contraction has on vocal fold vibration as evaluated with high-speed videoendoscopy, and to identify one or more aspects of the vocal fold vibration that could be used as an indicator of unilateral cricothyroid muscle paralysis. METHODS: We conducted an experimental study on 20 larynges excised from adult male human cadavers. Laryngeal vibration was artificially produced by compressed air passing through the vocal folds. Each larynx was assessed in three situations: bilateral cricothyroid muscle contraction, unilateral cricothyroid muscle contraction and no contraction of either cricothyroid muscle. The following parameters were evaluated by high-speed videoendoscopy: fundamental frequency, periodicity, amplitude of vocal fold vibration, and phase symmetry between the vocal folds. RESULTS: Although neither unilateral nor bilateral cricothyroid muscle contraction altered periodicity of vibration or the occurrence of phase asymmetry, there was a significant decrease in fundamental frequency in parallel with the decreasing longitudinal tension (p < 0,001). We also found an increase in vibration amplitude of right and left vocal folds (p < 0,05), which were similar in terms of their behavior for this parameter in the various situations studied. CONCLUSION: Decreased vocal fold tension caused by the absence of unilateral or bilateral contraction of cricothyroid muscle resulted in a decrease in fundamental frequency and an increase in vibration amplitude. The presence of regular periodicity in all studied larynges suggests that videostroboscopy, method most frequently used in clinical practice, may be a suitable method for the evaluation of patients with unilateral cricothyroid muscle paralysis. We also believe that unilateral cricothyroid muscle paralysis is not capable of causing a sufficient degree of tension asymmetry to induce phase asymmetry or a difference in vibration amplitude between the vocal folds and, hence, these parameters can\'t be used as reliable indicators of this condition

Master´s thesis deals with creating planar computational model of human folds, involving fluid-structure interaction. With this model, the influence of changes in vocal folds tissue layers (stiffness, thickness) and their effects on the videokymograph image are studied. Analysis of the results also deals with the evaluation of pressure at selected points below, between and above the vocal folds. The results indicate a possible similarity with the behavior of human vocal folds with pathology. Background research of vocal folds function, an overview of vocal folds pathology and summary of computational models are included.

This Master´s thesis deals with use of finite element method for modeling motion and stress of vocal folds during setting to phonation position. The thesis contains a description of the relevant anatomical structures and of the closely related formation of the human voice. A list of some previously published models of the function of human vocal folds follows. A part of my work was to create a model of geometry of the larynx using CATIA V5 and PTC Creo 2.0 on the basis of data acquired by MRI (magnetic resonance imaging). After that the model was converted into the calculation system Ansys Workbench 15.0 and, for solving contact problems, into Ansys Classic 15.0. To solve given problems, these programs use the finite element method (FEM). Solution was carried out for six different variants simulating individual motions of cartilages, corresponding to the activation of individual muscles. For each variant, the movements and stresses in the soft tissue of the vocal folds were evaluated. For variants with activation of IA, TA and LCA muscle it was also evaluated the contact pressure between the vocal folds. Finally, the thesis mentions the preparation of the model for the activation of the vocal folds movement by the muscles of the larynx.

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Computational models of the flow-induced vibrations of the vocal folds are powerful tools that can be used in conjunction with physical experiments to better understand voice production. This thesis research has been performed to contribute to the understanding of vocal fold dynamics as well as several aspects of computational modeling of the vocal folds. In particular, the effects of supraglottal geometry have been analyzed using a computational model of the vocal folds and laryngeal airway. In addition, three important computational modeling parameters (contact line location, Poisson's ratio, and symmetry assumptions) have been systematically varied to determine their influence on model output. Variations in model response were quantified by comparing glottal width, frequency, flow rate, open quotient, pressures, and wave velocity measures. In addition, the glottal jet was qualitatively analyzed. It was found that for various supraglottal geometries (either symmetrically or asymmetrically positioned), there was little asymmetry of the vocal fold motion despite significant asymmetry in the glottal jet. In addition, the vocal fold motion was most symmetric when consistent jet deflection was present (even if asymmetric). Inconsistent deflection of the glottal jet led to slightly larger asymmetries in vocal fold motion. The contact line location was found to have minimal impact on glottal width, frequency, and flow rate. The largest influence of the contact line location was seen in predicted velocity fields during the closed phase and in the pressure profiles along the vocal fold surfaces. Variations in Poisson's ratio strongly affected vocal fold motion, with lower Poisson's ratios resulting in larger amplitudes. The model did not vibrate when a Poisson's ratio of 0.49999 was used. The response of a full model (with two vocal folds) was shown to vary slightly from that of a half model (one vocal fold and a symmetry boundary condition), the greatest difference being in the deflection and dissipation of the glottal jet. It was concluded that for many scenarios the half model will be sufficient for modeling vocal fold motion; however, a full model is suggested for studies of material asymmetry or glottal jet dynamics. Application of these results to computational models of the vocal folds will lead to improved modeling and understanding of vocal fold dynamics.

Voice quality is strongly linked to quality of life; those who suffer from voice disorders are adversely affected in their social, family, and professional relationships. An effort has been made to more fully understand the physics behind how the voice is created, specifically the fluid structure interactions that occur during vocal fold vibration. Many techniques have been developed and implemented to study both the motion of the vocal folds and the airflow that creates the motion. Until recently these techniques have sought to understand a highly three-dimensional phenomenon with 1D or 2D perspectives.This research focuses on the development and implementation of an experimental technique to obtain three-dimensional characterizations of vocal fold motion and fluid flow. Experiments were performed on excised human vocal fold models at the University Hospital Erlangen Medical School in Erlangen, Germany. A novel technique for tracking the motion of the vocal folds using multiple camera viewpoints and limited user interaction was developed. Four high-speed cameras (2000 fps) recorded an excised vocal fold model vibrating at 250 Hz. Based on the images from these four cameras a fully 3D reconstruction of the superior surface of the vocal folds was achieved. The 3D reconstruction of 70 consecutive time steps was assembled to characterize the motion of the vocal folds over eight cycles. The 3D reconstruction accurately modeled the observed behavior of vocal fold vibration with a clearly visible mucosal wave. The average reprojection error for this technique was on par with other contemporary techniques (~20 micrometers). A whole field, time resolved, three-dimensional reconstruction of the vocal fold fluid flow was obtained using synthetic aperture particle image velocimetry. Simultaneous 3D flow fields, subglottal pressure waves, and superior surface motion were presented for 2 consecutive cycles of oscillation. The vocal fold fluid flow and motion measurements correlated with behavior observed in previous three-dimensional studies. A higher resolution view of one full cycle of oscillation was compiled from 16 time resolved data sets via pressure data. The result was a full three-dimensional characterization of the evolution and disintegration of the glottal jet.

Wechselnde Richtungen von Flächen in unterschiedlichen „Amplituden“ ... – Das Leporello kann in seinen unterschiedlichen Ausdehnungen in verschiedener Weise gesehen, gelesen werden: nach außen, über die Faltungen oben und unten sich öffnend – oder – von außen über die obere und unterer Ebene einander zusammenführend.

Introduction: Exercise-induced laryngeal obstruction (EILO) is a condition associated with stridor, wheezing and dyspnea during exercise. The condition is commonly divided into two subtypes, glottic and supraglottic, depending on the level of the obstruction in the larynx. The obstruction may also occur in a combined form. At Uppsala University Hospital there are a few different treatment options for EILO but they are most commonly referred to speech and language pathology treatment (SLP-treatment).    Objectives: The purpose of this study was to examine (1) the perceived effect of SLP-treatment on individuals with EILO and (2) to examine whether a difference in the perceived effect was due to type of EILO. A third aim (3) was to examine the presence of voice symptoms in this group.   Study designs:This study investigated separate objectives and reported results from both a retrospective cross-sectional study and a cross-sectional study.    Methods:51 participants with EILO were referred to SLP-treatment between year 2007 and 2017. 37 of the participants completed a survey on the perceived effect of SLP-treatment. All participants answered a questionnaire about voice symptoms, Screen6.   Results: A majority, 54% of the 37 participants who had undergone SLP-treatment, reported being helped by the treatment. In total, 51 participants diagnosed with EILO answered the survey, generating a response rate of 52%. The result showed that 31 % of the participants reported voice problems. Voice problems were defined as having two or more voice symptoms weekly or daily on Screen6.    Conclusions:(1) In this study a majority of the participants reported SLP-treatment as helpful. (2) No significant difference between the perceived effect of the intervention and type of EILO existed. (3) 31% of the participants had a voice problem according to Screen6. This number is higher, than in the general population and in other risk groups and may indicate a greater risk of voice disorders in individuals with EILO.

Este trabalho propõe direcionar o estudo de involuções para dois ramos de pesquisa dentro da teoria das Singularidades e de Sistemas Dinâmicos. Mais precisamente, tratamos sua interligação com diagramas divergentes de dobras e seu aparecimento nos sistemas dinâmicos discretos reversíveis. No primeiro, tratamos da importante relação entre a classificação de diagramas divergentes de dobras, digamos de s dobras, e a classificação de s-uplas de involuções associadas a estes diagramas. No segundo contexto, o estudo se volta para a questão sobre condições para a linearização simultânea de uma classe de pares de involuções e a obtenção de formas normais desses pares / This work proposes to address the study of involutions for two branches of research into the theory of Singularities and Dynamical Systems. More precisely, we treat its interconnection with divergent diagrams of folds and their appearance in discrete reversible dynamical systems. First, we treat the important relationship between the classification of divergent diagrams of folds, say s folds, and the classification of s-tuples of involutions associated with these diagrams. In the second context, the study turns to the question of conditions for simultaneous linearization of a class of pairs of involutions and the deduction of the normal forms of these pairs

A disfunção das pregas vocais (DPV) é caracterizada por movimento paradoxal de fechamento das pregas vocais, ocorrendo de forma episódica e involuntária durante a inspiração, levando à obstrução das vias aéreas. Os pacientes que apresentam DPV costumam não responder ao tratamento indicado para asma, levando ao uso inapropriado de corticóides sistêmicos com efeitos colaterais, freqüentes passagens em setores de emergência, hospitalizações por vezes desnecessárias e, com menos freqüência, intubação e traqueostomia. O objetivo principal deste estudo foi o de investigar a relação desta problemática com a economia psíquica destes pacientes, no que diz respeito à psicogênese e as possibilidades de tratamento por meio do método clínico de investigação e tratamento psicanalíticos. Para isto, foram incluídos 5 pacientes do sexo feminino, com idades entre 30 e 55 anos, que foram acompanhadas em tratamento psicanalítico no ambulatório do Serviço de Imunologia Clínica e Alergia do Instituto Central do HCFMUSP. Constatamos que a DPV aparece de maneira singular na vida de cada paciente investigada, porém com características peculiares que indicam uma localização psíquica capaz de operar como uma satisfação inconsciente frente a um conflito anterior. A princípio, abordar a paciente como se esta não possuísse asma pode levar a uma reação negativa, interpretada por elas como um fingimento ou uma estratégia consciente de obter ganhos primários. A interlocução entre o psicanalista e os demais profissionais da equipe mostra-se de significativa importância / Vocal fold dysfunction (VFD) is characterized by paradoxical movement of closing of the vocal folds, occurring of irregularly and involuntary form during the inspiration, leading to the blockage of the aerial ways. The patients who present VFD do not answer to the treatment indicated for asthma, leading to the unnecessary use of systemic steroids with collateral effect, frequent visits in emergency sectors, hospitalizations and, sometimes, intubations and tracheotomies. The main objective of this study was to investigate the relation of this problematic and the psychic economy of these patients, in whom it says respect to psychogenic explanation and the possibilities of psychoanalytical treatment. For this, 5 patients of the feminine sex had been enclosed, with ages between 30 and 55 years, that had been followed in psychoanalytical treatment in the clinic of the Service of Clinical Imunologia and Allergy of the Central Institute of the HCFMUSP. We evidence that the VFD appears in singular way in the life of each investigated patient, however with peculiar characteristics that indicate a psychic localization capable to operate as an unconscious satisfaction to a previous conflict. To approach the patient as if this did not possess asthma can lead to a negative reaction, interpreted for them as a deceit or a conscientious strategy to get primary profits. The interlocution between the psychoanalyst and the members of the team reveals of significant importance