Evaluation of a new self-contained, ambulatory, objective cough monitor

OBJECTIVE AND BACKGROUND: Objective monitoring of cough may be preferred to subjective reporting of the symptom in clinical and research settings. Therefore, a self-contained, ambulatory cough monitoring system is needed that is non-invasive, usable for children and adults of all ages, inexpensive, and highly accurate with easy to use analysis software. METHODOLOGY: After development of a new device, 15 subjects with frequent coughing were recorded with the novel cough monitor and a simultaneous video recording in order to validate the monitor compared with a gold standard. Two investigators independently analyzed the recordings and counted the number of coughs during the study period from both the cough monitor and the video recording. RESULTS: When measuring agreement between the two investigators, the sample concordance correlation coefficient for audio counts was 0.998 (p < 0.001). In the comparison of video counts, the sample concordance correlation coefficient was 0.997 (p < 0.001). For the comparison of investigator 1's video counts to the corresponding audio counts, the sample concordance correlation coefficient was 0.968 (p = 0.026). For the comparison of investigator 2's video counts to the corresponding counts, the sample concordance correlation coefficient was 0.973 (p = 0.015). CONCLUSION: We have developed and piloted a new, valid, and reproducible method of objectively recording and analyzing cough. This device appears to be useful for subjects of any age and in clinical and research settings

Plataforma para gestão de pacientes com doenças respiratórias crónicas

Mestrado em Engenharia de Computadores e TelemáticaAs doenças respiratórias são uma das razões mais frequentes para consultas médicas e uma das causas de morte mais frequentes a nível mundial, representando gastos de vários milhões de euros. A frequência e grau de severidade de ocorrência de tosse é um dos principais indicadores a analisar, por ser este o sintoma mais frequente em grande parte destas doenças respiratórias e por ser também um bom indicador da evolução do estado do paciente. Dada a importância deste sintoma, foi desenvolvido o Leicester Cough Monitor, uma aplicação que permite obter, de forma automática e não invasiva, dados quantitativos fiáveis relativos à frequência de ocorrência de tosse. Contudo, essa aplicação funciona apenas em modo local, tendo esta de estar instalada no computador onde se deseje realizar o estudo não havendo qualquer tipo de ligação e comunicação entre mais que um computador. Dado este facto, não é possível manter de forma eficiente um sincronismo de informação e de estudos realizados em mais que um computador ou em diferentes centros. O trabalho descrito nesta dissertação teve como objectivo fundamental desenvolver uma plataforma Web que, através da integração da ferramenta LCM já existente, permita a realização de estudos sobre a evolução dos sintomas de tosse de vários pacientes. Foi então desenvolvida uma plataforma que permite ter informação organizada, sincronizada e reunida num único ponto estando esta acessível de qualquer local com acesso à Internet. A disponibilização das várias funcionalidades da ferramenta LCM numa vertente Web foi o foco principal, sendo que novas funcionalidades foram criadas de modo a permitir de uma forma organizada e controlada a gestão de toda a informação com a implementação de um sistema de gestão de utilizadores.Respiratory diseases are one of the most frequent reasons for medical appointments and one of the main causes of death worldwide, accounting costs of several millions of Euros. The frequency and severity of occurrence of cough is one of the most important indicators, being the most frequent symptom in many of these diseases and also a good indicator of the evolution of the patient’s disease state. Given the importance of this symptom, the Leicester Cough Monitor, an application that allows obtaining, in an automatic and noninvasively way, reliable quantitative data on the frequency of occurrence of cough, was developed. However, this application only works locally, requiring that it is installed on the computer where we want to perform the study with no other kind of connection and communication between more than one computer. Given this fact, it is not possible to efficiently maintain synchronism of information and studies on more than one computer or between different centers. The work described in this dissertation had as fundamental goal the development of a Web platform that, through the integration of the existing LCM tool, enables studies of the evolution of patients with various symptoms of cough. Thus, a platform was developed that allows having information organized, synchronized and collected at a single point being this accessible from any location with Internet access. The availability of the various functionalities of the LCM tool on a Web context was the main focus, and new features were created to allow an organized and controlled management of all information with the implementation of a user management system

Measurement and analysis of breath sounds

Existing breath sound measurement systems and possible new methods have been critically investigated. The frequency response of each part of the measurement system has been studied. Emphasis has been placed on frequency response of acoustic sensors; especially, a method to study a diaphragm type air-coupler in contact use has been proposed. Two new methods of breath sounds measurement have been studied: laser Doppler vibrometer and mobile phones. It has been shown that these two methods can find applications in breath sounds measurement, however there are some restrictions. A reliable automatic wheeze detection algorithm based on auditory modelling has been developed. That is the human’s auditory system is modelled as a bank of band pass filters, in which the bandwidths are frequency dependent. Wheezes are treated as signals additive to normal breath sounds (masker). Thus wheeze is detectable when it is above the masking threshold. This new algorithm has been validated using simulated and real data. It is superior to previous algorithms, being more reliable to detect wheezes and less prone to mistakes. Simulation of cardiorespiratory sounds and wheeze audibility tests have been developed. Simulated breath sounds can be used as a training tool, as well as an evaluation method. These simulations have shown that, under certain circumstance, there are wheezes but they are inaudible. It is postulated that this could also happen in real measurements. It has been shown that simulated sounds with predefined characteristics can be used as an objective method to evaluate automatic algorithms. Finally, the efficiency and necessity of heart sounds reduction procedures has been investigated. Based on wavelet decomposition and selective synthesis, heart sounds can be reduced with a cost of unnatural breath sounds. Heart sound reduction is shown not to be necessary if a time-frequency representation is used, as heart sounds have a fixed pattern in the time-frequency plane

Models and analysis of vocal emissions for biomedical applications

This book of Proceedings collects the papers presented at the 3rd International Workshop on Models and Analysis of Vocal Emissions for Biomedical Applications, MAVEBA 2003, held 10-12 December 2003, Firenze, Italy. The workshop is organised every two years, and aims to stimulate contacts between specialists active in research and industrial developments, in the area of voice analysis for biomedical applications. The scope of the Workshop includes all aspects of voice modelling and analysis, ranging from fundamental research to all kinds of biomedical applications and related established and advanced technologies

Models and analysis of vocal emissions for biomedical applications

This book of Proceedings collects the papers presented at the 4th International Workshop on Models and Analysis of Vocal Emissions for Biomedical Applications, MAVEBA 2005, held 29-31 October 2005, Firenze, Italy. The workshop is organised every two years, and aims to stimulate contacts between specialists active in research and industrial developments, in the area of voice analysis for biomedical applications. The scope of the Workshop includes all aspects of voice modelling and analysis, ranging from fundamental research to all kinds of biomedical applications and related established and advanced technologies