Hyaluronic Acid Behavior in the Lamina Propria of the Larynx with Advancing Age

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Alterations in extracellular matrix composition in the aging larynx

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

HOME RANGES AND MOVEMENTS OF COYOTES IN THE NORTHERN CHIHUAHUAN DESERT

The coyote (Canis latrans) is among the most studied animals in North America. Because of its adaptability and success as a predator, the coyote has flourished and is still expanding its range. Coyotes can now be found throughout most of North America and south into Central America (Voight and Berg 1987). Studies in recent years have been extensive to understand the interrelationships of prey and coyotes (Shelton and Klindt 1974, Beckoff and Wells 1981), as well as demographic relationships (Davis et al. 1975, Knowlton and Stoddart 1978, Mitchell 1979, Bowen 1981) and feeding strategies (Todd and Keith 1976, Andelt et al. 1987, MacCracken and Hansen 1987, Gese et al. 1988a). With the advance of radio telemetry, researchers have investigated lifestyle characteristics spatially with home ranges or temporally with movements in relation to habitat requirements. Researchers have studied home ranges of coyotes in various regions of the United States (Livaitis and Shaw 1980, Andelt 1981, Springer 1982, Pyrah 1984, Gese et al. 1988a) and Canada (Bowen 1982). Some studies of home range were separated by season (Ozoga and Harger 1966) or relation to nearby food sources (Danner and Smith 1980). Home range analysis in relation to social interactions of coyotes has been either neglected, overlooked, or avoided. Gese et al. (1988a) recognized a transient class of coyote by home range size. Coyote social systems are very complex and can vary by season or locality in addition to some reports of group or pack systems (Hamlin and Schweitzer 1979, Beckoff and Wells 1981, Bowen 1981, Gese et al. 1988b). Coyotes maintain communication with conspecifics through vocal and olfactory signals (Lehner 1987, Bowen and McTaggert Cowan 1980). Social interactions may be by far the most complex and least understood aspect related to coyote ecology. Coyote movements can be related to many factors including food, water, cover, and social interactions. Movements in relation to food sources are well documented (Fitch 1948, Todd and Keith 1976, Danner and Smith 1980) although reports on movements in relation to water have not been reported, probably because of limited research in desert situations. There has been some mention of coyotes' movements in relation to cover (Wells and Beckoff 1982). The objectives of this study were to delineate annual and seasonal home ranges, movements, and habitat use of coyotes in the northern Chihuahuan desert.

Endoscopic Laser Thyroarytenoid Myoneurectomy in Patients with Adductor Spasmodic Dysphonia: A Pilot Study on Long-Term Outcome on Voice Quality

Objectives. Adductor spasmodic dysphonia (ADSD) is a focal laryngeal dystonia, which compromises greatly the quality of life of the patients involved. It is a severe vocal disorder characterized by spasms of laryngeal muscles during speech, producing phonatory breaks, forced, strained and strangled voice. Its symptoms result from involuntary and intermittent contractions of thyroarytenoid muscle during speech, which causes vocal fold to strain, pressing each vocal fold against the other and increasing glottic resistance. Botulinum toxin injection remains the gold-standard treatment. However, as injections should be repeated periodically leading to voice quality instability, a more definitive procedure would be desirable. In this pilot study we report the long-term vocal quality results of endoscopic laser thyroarytenoid myoneurectomy. Study Design. Prospective study. Methods. Surgery was performed in 15 patients (11 females and four males), aged between 29 and 73 years, diagnosed with ADSD. Voice Handicap Index (VHI) was obtained before and after surgery (median 31 months postoperatively). Results. A significant improvement in VHI was observed after surgery, as compared with baseline values (P = 0.001). The median and interquartile range for preoperative VHI was 99 and 13, respectively and 24 and 42, for postoperative VHI. Subjective improvement of voice as assessed by the patients showed median improvement of 80%. Conclusions. Because long-term follow-up showed significant improvement of voice quality, this innovative surgical technique seems a satisfactory alternative treatment of ADSD patients who seek a definite improvement of their condition.

Individually Customized Implants for Laryngoplasty-Are They Possible?

Objective. To standardize the design of individually fitted implants based on computed tomographic (CT) images for use in medialization laryngoplasty without intraoperative voice monitoring. Study Design. Prospective tomographic and anatomical experimental study of 10 human cadaveric larynges. Methods. CT scans of 10 excised human larynges were analyzed to define the shape and size of ideal implants for medialization laryngoplasty. Silicone implants were designed according to CT parameters and used in simulated laryngoplasties in the laryngeal specimens. The efficacy of each implant in providing adequate medialization of the vocal fold was evaluated. Results. Diverse shapes and sizes of implants were obtained, reflecting variations in laryngeal anatomy. The implants enabled regular medialization of the entire extent of the free border of the vocal fold, including its posterior aspect. Medialization was considered adequate in all cases. Conclusions. This method proved to be a simple and efficient way to design individualized implants for medialization laryngoplasty, regardless of the size and shape of the larynx.

Psychiatric comorbidity in patients with spasmodic dysphonia: a controlled study

OBJECTIVES: To study the prevalence of psychiatric comorbidity assessed by a structured clinical interview in patients with spasmodic dysphonia (SD) compared with patients suffering from vocal fold paralysis (VFP). METHODS: In 48 patients with SD and 27 patients with VFP, overall psychiatric comorbidity was studied prospectively using the Structured Clinical Interview for DSM-IV Axis I disorders. Physical disability and psychometric variables were assessed with standardised self-rating questionnaires. RESULTS: 41.7% of SD subjects and 19.5% of the control group met DSM-IV clinical criteria for current psychiatric comorbidity (p<0.05). Significant predictors of psychiatric comorbidity in SD were severity of voice impairment and subjective assessment of "satisfaction with health". As a limitation, the severity of voice impairment in patients with SD was nearly twice as high, and their illness had lasted nearly twice as long. CONCLUSIONS: We found a high prevalence of psychiatric comorbidity in patients with SD. The significant correlation between current psychiatric comorbidity and the extent of voice pathology may point to an especially strong interaction between somatic and psychiatric complaints in SD.

Neurological Disease Detection and Monitoring from Voice Production

The dramatic impact of neurological degenerative pathologies in life quality is a growing concern. It is well known that many neurological diseases leave a fingerprint in voice and speech production. Many techniques have been designed for the detection, diagnose and monitoring the neurological disease. Most of them are costly or difficult to extend to primary attention medical services. Through the present paper it will be shown how some neurological diseases can be traced at the level of phonation. The detection procedure would be based on a simple voice test. The availability of advanced tools and methodologies to monitor the organic pathology of voice would facilitate the implantation of these tests. The paper hypothesizes that some of the underlying mechanisms affecting the production of voice produce measurable correlates in vocal fold biomechanics. A general description of the methodological foundations for the voice analysis system which can estimate correlates to the neurological disease is shown. Some study cases will be presented to illustrate the possibilities of the methodology to monitor neurological diseases by voice

Biomechanical evaluation of the singing voice

Teaching the adequate use of the singing voice conveys a lot of knowledge in musical performance as well as in objective estimation techniques involving the use of air, muscles, room and body acoustics, and the tuning of a fine instrument as the human voice. Although subjective evaluation and training is a very delicate task to be carried out only by expert singers, biomedical engineering may help contributing with well-funded methodologies developed for the study of voice pathology. The present work is a preliminary study of exploratory character describing the performance of a student singer in a regular classroom under the point of view of vocal fold biomechanics. Estimates of biomechanical parameters obtained from singing voice are given and their potential use is discussed.

Analysis of measured and simulated supraglottal acoustic waves

To date, although much attention has been paid to the estimation and modeling of the voice source (ie, the glottal airflow volume velocity), the measurement and characterization of the supraglottal pressure wave have been much less studied. Some previous results have unveiled that the supraglottal pressure wave has some spectral resonances similar to those of the voice pressure wave. This makes the supraglottal wave partially intelligible. Although the explanation for such effect seems to be clearly related to the reflected pressure wave traveling upstream along the vocal tract, the influence that nonlinear source-filter interaction has on it is not as clear. This article provides an insight into this issue by comparing the acoustic analyses of measured and simulated supraglottal and voice waves. Simulations have been performed using a high-dimensional discrete vocal fold model. Results of such comparative analysis indicate that spectral resonances in the supraglottal wave are mainly caused by the regressive pressure wave that travels upstream along the vocal tract and not by source-tract interaction. On the contrary and according to simulation results, source-tract interaction has a role in the loss of intelligibility that happens in the supraglottal wave with respect to the voice wave. This loss of intelligibility mainly corresponds to spectral differences for frequencies above 1500 Hz.

Descripción de parámetros glóticos basados en el modelado de los pliegues vocales para la detección de patología de la voz

Las patologías de la voz se han transformado en los últimos tiempos en una problemática social con cierto calado. La contaminación de las ciudades, hábitos como el de fumar, el uso de aparatos de aire acondicionado, etcétera, contribuyen a ello. Esto alcanza más relevancia en profesionales que utilizan su voz de manera frecuente, como, por ejemplo, locutores, cantantes, profesores o teleoperadores. Por todo ello resultan de especial interés las técnicas de ayuda al diagnóstico que son capaces de extraer conclusiones clínicas a partir de una muestra de la voz grabada con un micrófono, frente a otras invasivas que implican la exploración utilizando laringoscopios, fibroscopios o videoendoscopios, técnicas en cualquier caso mucho más molestas para los pacientes al exigir la introducción parcial del instrumental citado por la garganta, en actuaciones consideradas de tipo quirúrgico. Dentro de aquellas técnicas se ha avanzado mucho en un período de tiempo relativamente corto. En lo que se refiere al diagnóstico de patologías, hemos pasado en los últimos quince años de trabajar principalmente con parámetros extraídos de la señal de voz –tanto en el dominio del tiempo como en el de la frecuencia– y con escalas elaboradas con valoraciones subjetivas realizadas por expertos a hacerlo también con parámetros procedentes de estimaciones de la fuente glótica. La importancia de utilizar la fuente glótica reside, a grandes rasgos, en que se trata de una señal vinculada directamente al estado de la estructura laríngea del locutor y también en que está generalmente menos influida por el tracto vocal que la señal de voz. Es conocido que el tracto vocal guarda más relación con el mensaje hablado, y su presencia dificulta el proceso de detección de patología vocal. Estas estimaciones de la fuente glótica han sido obtenidas a través de técnicas de filtrado inverso desarrolladas por nuestro grupo de investigación. Hemos conseguido, además, profundizar en la naturaleza de la señal glótica: somos capaces de descomponerla y relacionarla con parámetros biomecánicos de los propios pliegues vocales, obteniendo estimaciones de elementos como la masa, la pérdida de energía o la elasticidad del cuerpo y de la cubierta del pliegue, entre otros. De las componentes de la fuente glótica surgen también los denominados parámetros biométricos, relacionados con la forma de la señal, que constituyen por sí mismos una firma biométrica del individuo. También trabajaremos con parámetros temporales, relacionados con las diferentes etapas que se observan dentro de la señal glótica durante un ciclo de fonación. Por último, consideraremos parámetros clásicos de perturbación y energía de la señal. En definitiva, contamos ahora con una considerable cantidad de parámetros glóticos que conforman una base estadística multidimensional, destinada a ser capaz de discriminar personas con voces patológicas o disfónicas de aquellas que no presentan patología en la voz o con voces sanas o normofónicas. Esta tesis doctoral se ocupa de varias cuestiones: en primer lugar, es necesario analizar cuidadosamente estos nuevos parámetros, por lo que ofreceremos una completa descripción estadística de los mismos. También estudiaremos cuestiones como la distribución de los parámetros atendiendo a criterios como el de normalidad estadística de los mismos, ocupándonos especialmente de la diferencia entre las distribuciones que presentan sujetos sanos y sujetos con patología vocal. Para todo ello emplearemos diferentes técnicas estadísticas: generación de elementos y diagramas descriptivos, pruebas de normalidad y diversos contrastes de hipótesis, tanto paramétricos como no paramétricos, que considerarán la diferencia entre los grupos de personas sanas y los grupos de personas con alguna patología relacionada con la voz. Además, nos interesa encontrar relaciones estadísticas entre los parámetros, de cara a eliminar posibles redundancias presentes en el modelo, a reducir la dimensionalidad del problema y a establecer un criterio de importancia relativa en los parámetros en cuanto a su capacidad discriminante para el criterio patológico/sano. Para ello se aplicarán técnicas estadísticas como la Correlación Lineal Bivariada y el Análisis Factorial basado en Componentes Principales. Por último, utilizaremos la conocida técnica de clasificación Análisis Discriminante, aplicada a diferentes combinaciones de parámetros y de factores, para determinar cuáles de ellas son las que ofrecen tasas de acierto más prometedoras. Para llevar a cabo la experimentación se ha utilizado una base de datos equilibrada y robusta formada por doscientos sujetos, cien de ellos pertenecientes al género femenino y los restantes cien al género masculino, con una proporción también equilibrada entre los sujetos que presentan patología vocal y aquellos que no la presentan. Una de las aplicaciones informáticas diseñada para llevar a cabo la recogida de muestras también es presentada en esta tesis. Los distintos estudios estadísticos realizados nos permitirán identificar aquellos parámetros que tienen una mayor contribución a la hora de detectar la presencia de patología vocal. Alguno de los estudios, además, nos permitirá presentar una ordenación de los parámetros en base a su importancia para realizar la detección. Por otra parte, también concluiremos que en ocasiones es conveniente realizar una reducción de la dimensionalidad de los parámetros para mejorar las tasas de detección. Por fin, las propias tasas de detección constituyen quizá la conclusión más importante del trabajo. Todos los análisis presentes en el trabajo serán realizados para cada uno de los dos géneros, de acuerdo con diversos estudios previos que demuestran que los géneros masculino y femenino deben tratarse de forma independiente debido a las diferencias orgánicas observadas entre ambos. Sin embargo, en lo referente a la detección de patología vocal contemplaremos también la posibilidad de trabajar con la base de datos unificada, comprobando que las tasas de acierto son también elevadas. Abstract Voice pathologies have become recently in a social problem that has reached a certain concern. Pollution in cities, smoking habits, air conditioning, etc. contributes to it. This problem is more relevant for professionals who use their voice frequently: speakers, singers, teachers, actors, telemarketers, etc. Therefore techniques that are capable of drawing conclusions from a sample of the recorded voice are of particular interest for the diagnosis as opposed to other invasive ones, involving exploration by laryngoscopes, fiber scopes or video endoscopes, which are techniques much less comfortable for patients. Voice quality analysis has come a long way in a relatively short period of time. In regard to the diagnosis of diseases, we have gone in the last fifteen years from working primarily with parameters extracted from the voice signal (both in time and frequency domains) and with scales drawn from subjective assessments by experts to produce more accurate evaluations with estimates derived from the glottal source. The importance of using the glottal source resides broadly in that this signal is linked to the state of the speaker's laryngeal structure. Unlike the voice signal (phonated speech) the glottal source, if conveniently reconstructed using adaptive lattices, may be less influenced by the vocal tract. As it is well known the vocal tract is related to the articulation of the spoken message and its influence complicates the process of voice pathology detection, unlike when using the reconstructed glottal source, where vocal tract influence has been almost completely removed. The estimates of the glottal source have been obtained through inverse filtering techniques developed by our research group. We have also deepened into the nature of the glottal signal, dissecting it and relating it to the biomechanical parameters of the vocal folds, obtaining several estimates of items such as mass, loss or elasticity of cover and body of the vocal fold, among others. From the components of the glottal source also arise the so-called biometric parameters, related to the shape of the signal, which are themselves a biometric signature of the individual. We will also work with temporal parameters related to the different stages that are observed in the glottal signal during a cycle of phonation. Finally, we will take into consideration classical perturbation and energy parameters. In short, we have now a considerable amount of glottal parameters in a multidimensional statistical basis, designed to be able to discriminate people with pathologic or dysphonic voices from those who do not show pathology. This thesis addresses several issues: first, a careful analysis of these new parameters is required, so we will offer a complete statistical description of them. We will also discuss issues such as distribution of the parameters, considering criteria such as their statistical normality. We will take special care in the analysis of the difference between distributions from healthy subjects and the distributions from pathological subjects. To reach these goals we will use different statistical techniques such as: generation of descriptive items and diagramas, tests for normality and hypothesis testing, both parametric and nonparametric. These latter techniques consider the difference between the groups of healthy subjects and groups of people with an illness related to voice. In addition, we are interested in finding statistical relationships between parameters. There are various reasons behind that: eliminate possible redundancies in the model, reduce the dimensionality of the problem and establish a criterion of relative importance in the parameters. The latter reason will be done in terms of discriminatory power for the criterion pathological/healthy. To this end, statistical techniques such as Bivariate Linear Correlation and Factor Analysis based on Principal Components will be applied. Finally, we will use the well-known technique of Discriminant Analysis classification applied to different combinations of parameters and factors to determine which of these combinations offers more promising success rates. To perform the experiments we have used a balanced and robust database, consisting of two hundred speakers, one hundred of them males and one hundred females. We have also used a well-balanced proportion where subjects with vocal pathology as well as subjects who don´t have a vocal pathology are equally represented. A computer application designed to carry out the collection of samples is also presented in this thesis. The different statistical analyses performed will allow us to determine which parameters contribute in a more decisive way in the detection of vocal pathology. Therefore, some of the analyses will even allow us to present a ranking of the parameters based on their importance for the detection of vocal pathology. On the other hand, we will also conclude that it is sometimes desirable to perform a dimensionality reduction in order to improve the detection rates. Finally, detection rates themselves are perhaps the most important conclusion of the work. All the analyses presented in this work have been performed for each of the two genders in agreement with previous studies showing that male and female genders should be treated independently, due to the observed functional differences between them. However, with regard to the detection of vocal pathology we will consider the possibility of working with the unified database, ensuring that the success rates obtained are also high.

Abordagem terapêutica da papilomatose laríngea : a propósito de um caso clínico

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2014

Involuntary glottal closure during inspiration in muscle tension dysphonia

Objective/Hypothesis: The purpose of this study was to examine respiratory function in a group of patients with muscle tension dysphonia (MTD) Design: Cross-sectional analytical study. Methods: Participants included 15 people with a diagnosis of MTD referred to speech pathology for management of their voice disorder, fiberoptic evidence of glottal or supraglottic constriction during phonation with or without posterior chink, or bowing combined and deviation in perceptual voice quality. A second group of 15 participants with no history of voice disorder served as healthy controls,. Baseline pulmonary function test measures included forced expiratory volume in the first second (FEV1), FVC, FEF25 to 75, FIF50, FEV1/FVC, ratio and FEF50/FIF50 ratio. Hypertonic saline challenge test measures included FEV1 and FIF50 after provocation, close response slope, and provocation dose. Results: Compared with healthy controls, participants with MTD demonstrated a higher prevalence of glottal constriction during inspiration after provocation with nebulized hypertonic saline as demonstrated by a reduction in FIF50 after the hypertonic saline challenge. There was no significant difference between the MTD and healthy control groups in baseline pulmonary function testing. Participants with MTD demonstrated a higher prevalence than healthy controls of abnormal glottic closure during inspiration similar to paradoxical vocal fold movement (PVFM). This suggests that they either had previously undiagnosed coexisting PVFM or that the condition of MTD could be expanded to include descriptions of aberrant glottic function during respiration. This study enhances the understanding of PVFM and MTD by combining research advances made in the fields of otolaryngology and respiratory medicine.

Surgical treatment of papillary thyroid carcinoma without lymph nodal involvement

Background. In the treatment of differentiated thyroid cancer (DTC), in absence of enlarged lymph nodes, the role of routine central lymph node dissection (RCLD) remains controversial. The aim of this study is to analyze data resulting from total thyroidectomy (TT) not combined with RCLD in the treatment of DTC. Methods. We retrospectively evaluated the clinical records of 80 patients treated between January 1996 and December 2003 with TT without RCLND, in absence of suspected enlarged lymph nodes at preoperative ultrasonography and intraoperatively during neck exploration. In this series, 75 patients (93.7%) underwent radioiodine (RAI) ablation, followed by Thyroid Stimulating Hormone (TSH) suppression therapy. In case of locoregional lymph nodal recurrence, a central (VI) and ipsilateral (III-IV) selective lymph node dissection was performed. Results. Incidence of permanent hypoparathyroidism (iPTH < 10 pg/ml) and unilateral temporary vocal fold paralysis were respectively 2.55% and 2.55%. Locoregional recurrence, with positive cervical lymph nodes, after a 10.3 ± 4.7 years mean follow-up was observed in 3 patients (3.75%). They were submitted to a central (VI) and ipsilateral (III-IV) selective neck dissection without significant complications. Conclusions. In our series, TT not combined with RCLD was associated to a low locoregional recurrence rate, even if the lack of a control group treated with RCLD does not allow any generalized assumption. RCLD may be indicated in high risk patients, in whom lymph nodal recurrence is more frequent. More prospective randomized studies are needed to better define the role of RCLD and postoperative radioiodine ablation.

Using dysphonic voice to characterize speaker's biometry

Phonation distortion leaves relevant marks in a speaker's biometric profile. Dysphonic voice production may be used for biometrical speaker characterization. In the present paper phonation features derived from the glottal source (GS) parameterization, after vocal tract inversion, is proposed for dysphonic voice characterization in Speaker Verification tasks. The glottal source derived parameters are matched in a forensic evaluation framework defining a distance-based metric specification. The phonation segments used in the study are derived from fillers, long vowels, and other phonation segments produced in spontaneous telephone conversations. Phonated segments from a telephonic database of 100 male Spanish native speakers are combined in a 10-fold cross-validation task to produce the set of quality measurements outlined in the paper. Shimmer, mucosal wave correlate, vocal fold cover biomechanical parameter unbalance and a subset of the GS cepstral profile produce accuracy rates as high as 99.57 for a wide threshold interval (62.08-75.04%). An Equal Error Rate of 0.64 % can be granted. The proposed metric framework is shown to behave more fairly than classical likelihood ratios in supporting the hypothesis of the defense vs that of the prosecution, thus ofering a more reliable evaluation scoring. Possible applications are Speaker Verification and Dysphonic Voice Grading.

Song selectivity and sensorimotor signals in vocal learning and production

Bird song, like human speech, is a learned vocal behavior that requires auditory feedback. Both as juveniles, while they learn to sing, and as adults, songbirds use auditory feedback to compare their own vocalizations with an internal model of a target song. Here we describe experiments that explore a role for the songbird anterior forebrain pathway (AFP), a basal ganglia-forebrain circuit, in evaluating song feedback and modifying vocal output. First, neural recordings in anesthetized, juvenile birds show that single AFP neurons are specialized to process the song stimuli that are compared during sensorimotor learning. AFP neurons are tuned to both the bird's own song and the tutor song, even when these stimuli are manipulated to be very different from each other. Second, behavioral experiments in adult birds demonstrate that lesions to the AFP block the deterioration of song that normally follows deafening. This observation suggests that deafening results in an instructive signal, indicating a mismatch between feedback and the internal song model, and that the AFP is involved in generating or transmitting this instructive signal. Finally, neural recordings from behaving birds reveal robust singing-related activity in the AFP. This activity is likely to originate from premotor areas and could be modulated by auditory feedback of the bird's own voice. One possibility is that this activity represents an efference copy, predicting the sensory consequences of motor commands. Overall, these studies illustrate that sensory and motor processes are highly interrelated in this circuit devoted to vocal learning, as is true for brain areas involved in speech.