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1.
HNO ; 70(1): 44-50, 2022 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-33837444

RESUMO

BACKGROUND: Recurrent and residual laryngeal cancer after organ-preserving radio- or radiochemotherapy is associated with a poor prognosis. Salvage surgery is the most important therapeutic option in these cases. OBJECTIVE: The study assessed rates of recurrence and residual tumor as well as survival and complication rates after salvage laryngectomy at the authors' academic cancer center. MATERIALS AND METHODS: A retrospective examination of all patients receiving laryngectomy between 2001 and 2019 due to tumor residuals or recurrence after primary radio- and radiochemotherapy was conducted. RESULTS: A total of 33 salvage procedures were performed. Defect reconstruction was performed by free flap surgery in 30.3% (n = 10) and regional flap surgery in 15.2% (n = 5) . One patient received regional flap surgery and free flap surgery simultaneously. Overall survival after 1, 2, and 5 years was 68.7, 47.9, and 24.2%, and disease-free survival was 81.6, 47.8, and 24.2%, respectively, with 48.5% (n = 16) postoperative tumor recurrences overall. Disease-free survival was significantly shorter for tumor extension into or onto the hypopharynx (p = 0.041). Postoperatively, 72.7% of patients developed a pharyngocutaneous fistula, of which 24.2% required surgical treatment. The hospital stay was 28.0 ± 16.1 days. CONCLUSION: Salvage laryngectomy is associated with a high rate of treatable complications and high morbidity. Nevertheless, considering the advanced tumor stages treated, it allows for respectable oncological results.


Assuntos
Fístula Cutânea , Retalhos de Tecido Biológico , Neoplasias Laríngeas , Quimiorradioterapia/efeitos adversos , Humanos , Neoplasias Laríngeas/cirurgia , Laringectomia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Terapia de Salvação
2.
HNO ; 69(Suppl 2): 47-52, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34019140

RESUMO

BACKGROUND: Recurrent and residual laryngeal cancer after organ-preserving radio- or radiochemotherapy is associated with a poor prognosis. Salvage surgery is the most important therapeutic option in these cases. OBJECTIVE: The study assessed rates of recurrence and residual tumor as well as survival and complication rates after salvage laryngectomy at the authors' academic cancer center. MATERIALS AND METHODS: A retrospective examination of all patients receiving laryngectomy between 2001 and 2019 due to tumor residuals or recurrence after primary radio- and radiochemotherapy was conducted. RESULTS: A total of 33 salvage procedures were performed. Defect reconstruction was performed by free flap surgery in 30.3% (n = 10) and regional flap surgery in 15.2% (n = 5) . One patient received regional flap surgery and free flap surgery simultaneously. Overall survival after 1, 2, and 5 years was 68.7, 47.9, and 24.2%, and disease-free survival was 81.6, 47.8, and 24.2%, respectively, with 48.5% (n = 16) postoperative tumor recurrences overall. Disease-free survival was significantly shorter for tumor extension into or onto the hypopharynx (p = 0.041). Postoperatively, 72.7% of patients developed a pharyngocutaneous fistula, of which 24.2% required surgical treatment. The hospital stay was 28.0 ± 16.1 days. CONCLUSION: Salvage laryngectomy is associated with a high rate of treatable complications and high morbidity. Nevertheless, considering the advanced tumor stages treated, it allows for respectable oncological results.


Assuntos
Retalhos de Tecido Biológico , Laringectomia , Quimiorradioterapia/efeitos adversos , Humanos , Recidiva Local de Neoplasia , Estudos Retrospectivos
3.
J Acoust Soc Am ; 144(1): 142, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30075689

RESUMO

Quantitative analysis of phonatory characteristics of rabbits has been widely neglected. However, preliminary studies established the rabbit larynx as a potential model of human phonation. This study reports quantitative data on phonation using ex vivo rabbit larynx models to achieve more insight into dependencies of three main components of the phonation process, including airflow, vocal fold dynamics, and the acoustic output. Sustained phonation was induced in 11 ex vivo rabbit larynges. For 414 phonatory conditions, vocal fold vibrations, acoustic, and aerodynamic parameters were analyzed as functions of longitudinal vocal fold pre-stress, applied air flow, and glottal closure insufficiency. Dimensions of the vocal folds were measured and histological data were analyzed. Glottal closure characteristics improved for increasing longitudinal pre-stress and applied airflow. For the subglottal pressure signal only the cepstral peak prominence showed dependency on glottal closure. In contrast, vibrational, acoustic, and aerodynamic parameters were found to be highly dependent on the degree of glottal closure: The more complete the glottal closure during phonation, the better the aerodynamic and acoustic characteristics. Hence, complete or at least partial glottal closure appears to enhance acoustic signal quality. Finally, results validate the ex vivo rabbit larynx as an effective model for analyzing the phonatory process.


Assuntos
Fenômenos Biomecânicos/fisiologia , Laringe/fisiologia , Fonação/fisiologia , Prega Vocal/fisiologia , Animais , Feminino , Pressão , Coelhos , Vibração , Distúrbios da Voz/fisiopatologia
4.
Biochem Biophys Res Commun ; 468(3): 463-70, 2015 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-26271592

RESUMO

Nanoparticles have belonged to various fields of biomedical research for quite some time. A promising site-directed application in the field of nanomedicine is drug targeting using magnetic nanoparticles which are directed at the target tissue by means of an external magnetic field. Materials most commonly used for magnetic drug delivery contain metal or metal oxide nanoparticles, such as superparamagnetic iron oxide nanoparticles (SPIONs). SPIONs consist of an iron oxide core, often coated with organic materials such as fatty acids, polysaccharides or polymers to improve colloidal stability and to prevent separation into particles and carrier medium [1]. In general, magnetite and maghemite particles are those most commonly used in medicine and are, as a rule, well-tolerated. The magnetic properties of SPIONs allow the remote control of their accumulation by means of an external magnetic field. Conjugation of SPIONs with drugs, in combination with an external magnetic field to target the nanoparticles (so-called "magnetic drug targeting", MDT), has additionally emerged as a promising strategy of drug delivery. Magnetic nanoparticle-based drug delivery is a sophisticated overall concept and a multitude of magnetic delivery vehicles have been developed. Targeting mechanism-exploiting, tumor-specific attributes are becoming more and more sophisticated. The same is true for controlled-release strategies for the diseased site. As it is nearly impossible to record every magnetic nanoparticle system developed so far, this review summarizes interesting approaches which have recently emerged in the field of targeted drug delivery for cancer therapy based on magnetic nanoparticles.


Assuntos
Antineoplásicos/administração & dosagem , Preparações de Ação Retardada/administração & dosagem , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/efeitos da radiação , Nanocápsulas/química , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/efeitos da radiação , Preparações de Ação Retardada/química , Preparações de Ação Retardada/efeitos da radiação , Humanos , Campos Magnéticos , Nanopartículas de Magnetita/administração & dosagem , Nanocápsulas/administração & dosagem , Nanocápsulas/efeitos da radiação
5.
Phys Rev Lett ; 112(7): 073901, 2014 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-24579599

RESUMO

All-optical switching is a technique in which a gate light pulse changes the transmission of a target light pulse without the detour via electronic signal processing. We take this to the quantum regime, where the incoming gate light pulse contains only one photon on average. The gate pulse is stored as a Rydberg excitation in an ultracold atomic gas using electromagnetically induced transparency. Rydberg blockade suppresses the transmission of the subsequent target pulse. Finally, the stored gate photon can be retrieved. A retrieved photon heralds successful storage. The corresponding postselected subensemble shows an extinction of 0.05. The single-photon switch offers many interesting perspectives ranging from quantum communication to quantum information processing.

6.
Phys Rev Lett ; 113(5): 053602, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25126919

RESUMO

An all-optical transistor is a device in which a gate light pulse switches the transmission of a target light pulse with a gain above unity. The gain quantifies the change of the transmitted target photon number per incoming gate photon. We study the quantum limit of one incoming gate photon and observe a gain of 20. The gate pulse is stored as a Rydberg excitation in an ultracold gas. The transmission of the subsequent target pulse is suppressed by Rydberg blockade, which is enhanced by a Förster resonance. The detected target photons reveal in a single shot with a fidelity above 0.86 whether a Rydberg excitation was created during the gate pulse. The gain offers the possibility to distribute the transistor output to the inputs of many transistors, thus making complex computational tasks possible.

7.
Nanomedicine ; 9(7): 961-71, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23669367

RESUMO

To treat tumours efficiently and spare normal tissues, targeted drug delivery is a promising alternative to conventional, systemic administered chemotherapy. Drug-carrying magnetic nanoparticles can be concentrated in tumours by external magnetic fields, preventing the nanomaterial from being cleared by metabolic burden before reaching the tumour. Therefore in Magnetic Drug Targeting (MDT) the favoured mode of application is believed to be intra-arterial. Here, we show that a simple yet versatile magnetic carrier-system (hydrodynamic particles diameter <200nm) accumulates the chemotherapeutic drug mitoxantrone efficiently in tumours. With MDT we observed the following drug accumulations relative to the recovery from all investigated tissues: tumour region: 57.2%, liver: 14.4%, kidneys: 15.2%. Systemic intra-venous application revealed different results: tumour region: 0.7%, liver: 14.4 % and kidneys: 77.8%. The therapeutic outcome was demonstrated by complete tumour remissions and a survival probability of 26.7% (P=0.0075). These results are confirming former pilot experiments and implying a milestone towards clinical studies. FROM THE CLINICAL EDITOR: This team of investigators studied drug carrying nanoparticles for magnetic drug targeting (MDT), demonstrating the importance of intra-arterial administration resulting in improved clinical outcomes in the studied animal model compared with intra-venous.


Assuntos
Sistemas de Liberação de Medicamentos , Nanopartículas de Magnetita/química , Mitoxantrona/uso terapêutico , Neoplasias/tratamento farmacológico , Animais , Feminino , Nanopartículas de Magnetita/ultraestrutura , Mitoxantrona/química , Mitoxantrona/farmacologia , Neoplasias/diagnóstico por imagem , Neoplasias/metabolismo , Neoplasias/patologia , Tamanho da Partícula , Coelhos , Radiografia , Espectrofotometria Infravermelho , Distribuição Tecidual
8.
Int J Mol Sci ; 14(4): 7341-55, 2013 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-23549268

RESUMO

Magnetic drug targeting (MDT) improves the integrity of healthy tissues and cells during treatment with cytotoxic drugs. An anticancer drug is bound to superparamagnetic iron oxide nanoparticles (SPION), injected into the vascular supply of the tumor and directed into the tumor by means of an external magnetic field. In this study, we investigated the impact of SPION, mitoxantrone (MTO) and SPIONMTO on cell viability in vitro and the nonspecific uptake of MTO into circulating leukocytes in vivo. MDT was compared with conventional chemotherapy. MTO uptake and the impact on cell viability were assessed by flow cytometry in a Jurkat cell culture. In order to analyze MTO loading of circulating leukocytes in vivo, we treated tumor-bearing rabbits with MDT and conventional chemotherapy. In vitro experiments showed a dose-dependent MTO uptake and reduction in the viability and proliferation of Jurkat cells. MTO and SPIONMTO showed similar cytotoxic activity. Non-loaded SPION did not have any effect on cell viability in the concentrations tested. Compared with systemic administration in vivo, MDT employing SPIONMTO significantly decreased the chemotherapeutic load in circulating leukocytes. We demonstrated that MDT spares the immune system in comparison with conventional chemotherapy.


Assuntos
Proliferação de Células/efeitos dos fármacos , Citotoxinas , Sistemas de Liberação de Medicamentos/métodos , Leucócitos/metabolismo , Campos Magnéticos , Nanopartículas de Magnetita/química , Neoplasias Experimentais , Animais , Citotoxinas/química , Citotoxinas/farmacologia , Feminino , Humanos , Células Jurkat , Leucócitos/patologia , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Coelhos
9.
J Voice ; 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37648625

RESUMO

OBJECTIVE: The first goal of this study was to investigate the coverage of laryngeal structures using two potential administration techniques for synthetic mucus: inhalation and lozenge ingestion. As a second research question, the study investigated the potential effects of these techniques on standardized voice assessment parameters. METHODS: Fluorescein was added to throat lozenges and to an inhalation solution to visualize the coverage of laryngeal structures through blue light imaging. The study included 70 vocally healthy subjects. Fifty subjects underwent administration via lozenge ingestion and 20 subjects performed the inhalation process. For the first research question, the recordings from the blue light imaging system were categorized to compare the extent of coverage on individual laryngeal structures objectively. Secondly, a standardized voice evaluation protocol was performed before and after each administration to determine any measurable effects of typical voice parameters. RESULTS: The administration via inhalation demonstrated complete coverage of all laryngeal structures, including the vocal folds, ventricular folds, and arytenoid cartilages, as visualized by the fluorescent dye. In contrast, the application of the lozenge predominantly covered the pharynx and laryngeal surface toward the aryepiglottic fold, but not the inferior structures. All in all, the comparison before and after administration showed no clear effect, although a minor deterioration of the acoustic signal was noted in the shimmer and cepstral peak prominence after the inhalation. CONCLUSIONS: Our findings indicate that the inhalation process is a more effective technique for covering deeper laryngeal structures such as the vocal folds and ventricular folds with synthetic mucus. This knowledge enables further in vivo studies on the role of laryngeal mucus in phonation in general, and how it can be substituted or supplemented for patients with reduced glandular activity as well as for heavy voice users.

10.
Phys Rev Lett ; 108(12): 122003, 2012 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-22540574

RESUMO

We determine the quark mass ratio m(c)/m(s) on the lattice, using Wilson-type fermions. Configurations with N(f)=2 dynamical clover-improved fermions by the QCDSF Collaboration are used, which were made available through the ILDG. In the valence sector we use a sophisticated, mass-independently O(a)-improved Wilson-type action with small cutoff effects even in the charm mass region. After an extrapolation to the physical pion mass, to zero lattice spacing and to infinite box volume, we find m(c)/m(s)=11.27(30)(26).

11.
Phys Rev Lett ; 109(26): 263602, 2012 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-23368561

RESUMO

A classical logic gate connecting input and output light pulses is demonstrated. The gate operation is based on three steps: First, two incoming light pulses are stored in a Bose-Einstein condensate; second, atomic four-wave mixing generates a new matter wave; and third, the light pulses are retrieved. In the presence of the new matter wave, the retrieval generates a new optical wave. The latter will only be generated if both input light pulses are applied, thus realizing an AND gate. Finally, we show that the gate operation is phase coherent, an essential prerequisite for a quantum logic gate.

12.
PLoS One ; 17(9): e0266989, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36129922

RESUMO

Deep Learning has a large impact on medical image analysis and lately has been adopted for clinical use at the point of care. However, there is only a small number of reports of long-term studies that show the performance of deep neural networks (DNNs) in such an environment. In this study, we measured the long-term performance of a clinically optimized DNN for laryngeal glottis segmentation. We have collected the video footage for two years from an AI-powered laryngeal high-speed videoendoscopy imaging system and found that the footage image quality is stable across time. Next, we determined the DNN segmentation performance on lossy and lossless compressed data revealing that only 9% of recordings contain segmentation artifacts. We found that lossy and lossless compression is on par for glottis segmentation, however, lossless compression provides significantly superior image quality. Lastly, we employed continual learning strategies to continuously incorporate new data into the DNN to remove the aforementioned segmentation artifacts. With modest manual intervention, we were able to largely alleviate these segmentation artifacts by up to 81%. We believe that our suggested deep learning-enhanced laryngeal imaging platform consistently provides clinically sound results, and together with our proposed continual learning scheme will have a long-lasting impact on the future of laryngeal imaging.


Assuntos
Laringe , Sistemas Automatizados de Assistência Junto ao Leito , Artefatos , Glote/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Laringe/diagnóstico por imagem , Redes Neurais de Computação
13.
Sci Rep ; 12(1): 14292, 2022 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-35995933

RESUMO

Glottis segmentation is a crucial step to quantify endoscopic footage in laryngeal high-speed videoendoscopy. Recent advances in deep neural networks for glottis segmentation allow for a fully automatic workflow. However, exact knowledge of integral parts of these deep segmentation networks remains unknown, and understanding the inner workings is crucial for acceptance in clinical practice. Here, we show that a single latent channel as a bottleneck layer is sufficient for glottal area segmentation using systematic ablations. We further demonstrate that the latent space is an abstraction of the glottal area segmentation relying on three spatially defined pixel subtypes allowing for a transparent interpretation. We further provide evidence that the latent space is highly correlated with the glottal area waveform, can be encoded with four bits, and decoded using lean decoders while maintaining a high reconstruction accuracy. Our findings suggest that glottis segmentation is a task that can be highly optimized to gain very efficient and explainable deep neural networks, important for application in the clinic. In the future, we believe that online deep learning-assisted monitoring is a game-changer in laryngeal examinations.


Assuntos
Glote , Laringe , Endoscopia , Glote/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Gravação em Vídeo
14.
Sci Rep ; 11(1): 13760, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215788

RESUMO

High-speed videoendoscopy is an important tool to study laryngeal dynamics, to quantify vocal fold oscillations, to diagnose voice impairments at laryngeal level and to monitor treatment progress. However, there is a significant lack of an open source, expandable research tool that features latest hardware and data analysis. In this work, we propose an open research platform termed OpenHSV that is based on state-of-the-art, commercially available equipment and features a fully automatic data analysis pipeline. A publicly available, user-friendly graphical user interface implemented in Python is used to interface the hardware. Video and audio data are recorded in synchrony and are subsequently fully automatically analyzed. Video segmentation of the glottal area is performed using efficient deep neural networks to derive glottal area waveform and glottal midline. Established quantitative, clinically relevant video and audio parameters were implemented and computed. In a preliminary clinical study, we recorded video and audio data from 28 healthy subjects. Analyzing these data in terms of image quality and derived quantitative parameters, we show the applicability, performance and usefulness of OpenHSV. Therefore, OpenHSV provides a valid, standardized access to high-speed videoendoscopy data acquisition and analysis for voice scientists, highlighting its use as a valuable research tool in understanding voice physiology. We envision that OpenHSV serves as basis for the next generation of clinical HSV systems.


Assuntos
Glote/cirurgia , Doenças da Laringe/cirurgia , Laringoscopia/métodos , Laringe/cirurgia , Adolescente , Adulto , Feminino , Glote/diagnóstico por imagem , Glote/fisiopatologia , Humanos , Doenças da Laringe/diagnóstico por imagem , Doenças da Laringe/patologia , Laringoscopia/instrumentação , Laringe/diagnóstico por imagem , Laringe/patologia , Masculino , Pessoa de Meia-Idade , Redes Neurais de Computação , Gravação em Vídeo , Prega Vocal/diagnóstico por imagem , Prega Vocal/fisiopatologia , Prega Vocal/cirurgia , Voz/fisiologia , Distúrbios da Voz/diagnóstico por imagem , Distúrbios da Voz/fisiopatologia , Distúrbios da Voz/cirurgia , Qualidade da Voz/fisiologia , Adulto Jovem
15.
PLoS One ; 16(2): e0246136, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33529244

RESUMO

In voice research, uncovering relations between the oscillating vocal folds, being the sound source of phonation, and the resulting perceived acoustic signal are of great interest. This is especially the case in the context of voice disorders, such as functional dysphonia (FD). We investigated 250 high-speed videoendoscopy (HSV) recordings with simultaneously recorded acoustic signals (124 healthy females, 60 FD females, 44 healthy males, 22 FD males). 35 glottal area waveform (GAW) parameters and 14 acoustic parameters were calculated for each recording. Linear and non-linear relations between GAW and acoustic parameters were investigated using Pearson correlation coefficients (PCC) and distance correlation coefficients (DCC). Further, norm values for parameters obtained from 250 ms long sustained phonation data (vowel /i/) were provided. 26 PCCs in females (5.3%) and 8 in males (1.6%) were found to be statistically significant (|corr.| ≥ 0.3). Only minor differences were found between PCCs and DCCs, indicating presence of weak non-linear dependencies between parameters. Fundamental frequency was involved in the majority of all relevant PCCs between GAW and acoustic parameters (19 in females and 7 in males). The most distinct difference between correlations in females and males was found for the parameter Period Variability Index. The study shows only weak relations between investigated acoustic and GAW-parameters. This indicates that the reduction of the complex 3D glottal dynamics to the 1D-GAW may erase laryngeal dynamic characteristics that are reflected within the acoustic signal. Hence, other GAW parameters, 2D-, 3D-laryngeal dynamics and vocal tract parameters should be further investigated towards potential correlations to the acoustic signal.


Assuntos
Disfonia/fisiopatologia , Glote/fisiopatologia , Laringoscopia/métodos , Acústica , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Laringoscopia/instrumentação , Masculino , Pessoa de Meia-Idade , Gravação em Vídeo , Qualidade da Voz , Adulto Jovem
16.
J Speech Lang Hear Res ; 64(6): 1889-1903, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34000199

RESUMO

Purpose High-speed videoendoscopy (HSV) is an emerging, but barely used, endoscopy technique in the clinic to assess and diagnose voice disorders because of the lack of dedicated software to analyze the data. HSV allows to quantify the vocal fold oscillations by segmenting the glottal area. This challenging task has been tackled by various studies; however, the proposed approaches are mostly limited and not suitable for daily clinical routine. Method We developed a user-friendly software in C# that allows the editing, motion correction, segmentation, and quantitative analysis of HSV data. We further provide pretrained deep neural networks for fully automatic glottis segmentation. Results We freely provide our software Glottis Analysis Tools (GAT). Using GAT, we provide a general threshold-based region growing platform that enables the user to analyze data from various sources, such as in vivo recordings, ex vivo recordings, and high-speed footage of artificial vocal folds. Additionally, especially for in vivo recordings, we provide three robust neural networks at various speed and quality settings to allow a fully automatic glottis segmentation needed for application by untrained personnel. GAT further evaluates video and audio data in parallel and is able to extract various features from the video data, among others the glottal area waveform, that is, the changing glottal area over time. In total, GAT provides 79 unique quantitative analysis parameters for video- and audio-based signals. Many of these parameters have already been shown to reflect voice disorders, highlighting the clinical importance and usefulness of the GAT software. Conclusion GAT is a unique tool to process HSV and audio data to determine quantitative, clinically relevant parameters for research, diagnosis, and treatment of laryngeal disorders. Supplemental Material https://doi.org/10.23641/asha.14575533.


Assuntos
Aprendizado Profundo , Laringe , Glote , Humanos , Laringoscopia , Fonação , Software , Vibração , Gravação em Vídeo , Prega Vocal
17.
Phys Rev Lett ; 105(16): 160402, 2010 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-21230951

RESUMO

We propose a novel realization of Anderson localization in nonequilibrium states of ultracold atoms in an optical lattice. A Rabi pulse transfers part of the population to a different internal state with infinite effective mass. These frozen atoms create a quantum superposition of different disorder potentials, localizing the mobile atoms. For weakly interacting mobile atoms, Anderson localization is obtained. The localization length increases with increasing disorder and decreasing interaction strength, contrary to the expectation for equilibrium localization.

18.
Sci Rep ; 10(1): 10517, 2020 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-32601277

RESUMO

In voice research and clinical assessment, many objective parameters are in use. However, there is no commonly used set of parameters that reflect certain voice disorders, such as functional dysphonia (FD); i.e. disorders with no visible anatomical changes. Hence, 358 high-speed videoendoscopy (HSV) recordings (159 normal females (NF), 101 FD females (FDF), 66 normal males (NM), 32 FD males (FDM)) were analyzed. We investigated 91 quantitative HSV parameters towards their significance. First, 25 highly correlated parameters were discarded. Second, further 54 parameters were discarded by using a LogitBoost decision stumps approach. This yielded a subset of 12 parameters sufficient to reflect functional dysphonia. These parameters separated groups NF vs. FDF and NM vs. FDM with fair accuracy of 0.745 or 0.768, respectively. Parameters solely computed from the changing glottal area waveform (1D-function called GAW) between the vocal folds were less important than parameters describing the oscillation characteristics along the vocal folds (2D-function called Phonovibrogram). Regularity of GAW phases and peak shape, harmonic structure and Phonovibrogram-based vocal fold open and closing angles were mainly important. This study showed the high degree of redundancy of HSV-voice-parameters but also affirms the need of multidimensional based assessment of clinical data.


Assuntos
Endoscopia , Aprendizado de Máquina , Distúrbios da Voz/diagnóstico , Qualidade da Voz/fisiologia , Fatores Etários , Feminino , Humanos , Laringoscopia , Masculino , Distúrbios da Voz/fisiopatologia
19.
IEEE J Transl Eng Health Med ; 8: 2100511, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32518739

RESUMO

BACKGROUND: Various voice assessment tools, such as questionnaires and aerodynamic voice characteristics, can be used to assess vocal function of individuals. However, not much is known about the best combinations of these parameters in identification of functional dysphonia in clinical settings. METHODS: This study investigated six scores from clinically commonly used questionnaires and seven acoustic parameters. 514 females and 277 males were analyzed. The subjects were divided into three groups: one healthy group (N01) (49 females, 50 males) and two disordered groups with perceptually hoarse (FD23) (220 females, 96 males) and perceptually not hoarse (FD01) (245 females, 131 males) sounding voices. A tree stumps Adaboost approach was applied to find the subset of parameters that best separates the groups. Subsequently, it was determined if this parameter subset reflects treatment outcome for 120 female and 51 male patients by pairwise pre- and post-treatment comparisons of parameters. RESULTS: The questionnaire "Voice-related-quality-of-Life" and three objective parameters ("maximum fundamental frequency", "maximum Intensity" and "Jitter Percent") were sufficient to separate the groups (accuracy ranging from 0.690 (FD01 vs. FD23, females) to 0.961 (N01 vs. FD23, females)). Our study suggests that a reduced parameter subset (4 out of 13) is sufficient to separate these three groups. All parameters reflected treatment outcome for patients with hoarse voices, Voice-related-quality-of-Life showed improvement for the not hoarse group (FD01). CONCLUSION: Results show that single parameters are insufficient to separate voice disorders but a set of several well-chosen parameters is. These findings will help to optimize and reduce clinical assessment time.

20.
Sci Data ; 7(1): 186, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32561845

RESUMO

Laryngeal videoendoscopy is one of the main tools in clinical examinations for voice disorders and voice research. Using high-speed videoendoscopy, it is possible to fully capture the vocal fold oscillations, however, processing the recordings typically involves a time-consuming segmentation of the glottal area by trained experts. Even though automatic methods have been proposed and the task is particularly suited for deep learning methods, there are no public datasets and benchmarks available to compare methods and to allow training of generalizing deep learning models. In an international collaboration of researchers from seven institutions from the EU and USA, we have created BAGLS, a large, multihospital dataset of 59,250 high-speed videoendoscopy frames with individually annotated segmentation masks. The frames are based on 640 recordings of healthy and disordered subjects that were recorded with varying technical equipment by numerous clinicians. The BAGLS dataset will allow an objective comparison of glottis segmentation methods and will enable interested researchers to train their own models and compare their methods.


Assuntos
Endoscopia , Glote/fisiologia , Gravação em Vídeo , Prega Vocal/fisiologia , Distúrbios da Voz/diagnóstico , Glote/diagnóstico por imagem , Humanos , Prega Vocal/diagnóstico por imagem
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