Continuous Local Histogram Descriptor For Diagnosis of Bronchiolitis Obliterans

Texture feature is an important feature analysis method in computer-aided diagnosis systems for disease diagnosis. However, texture feature itself could not provide an overall description of the diseases. In this paper, we propose Continuous Local Feature (CLH) to diagnose the Bronchiolitis Obliterans (BO) lung diseases in the chest computer tomography images. CLH is based on the continuous combination of histograms of local texture feature, local shape feature, and the brightness feature. Because CLH extracts more information, it has high discriminating power and is able to classify between the BO lung disease and normal lung region effectively. The experimental results in classifying between BO and normal lung region show that CLH achieves 98.15% of average sensitivity whereas Local Binary Patterns and Gray Level Run Length Matrix achieve 73% and 75.8% of average sensitivities, respectively. In the receiver operating curve analysis, CLH archives 0.9 of area under curve (AUC) whereas LBP and GLRLM achieve 0.78 and 0.86 of AUCs

Texture Analysis and Machine Learning to Predict Pulmonary Ventilation from Thoracic Computed Tomography

Chronic obstructive pulmonary disease (COPD) leads to persistent airflow limitation, causing a large burden to patients and the health care system. Thoracic CT provides an opportunity to observe the structural pathophysiology of COPD, whereas hyperpolarized gas MRI provides images of the consequential ventilation heterogeneity. However, hyperpolarized gas MRI is currently limited to research centres, due to the high cost of gas and polarization equipment. Therefore, I developed a pipeline using texture analysis and machine learning methods to create predicted ventilation maps based on non-contrast enhanced, single-volume thoracic CT. In a COPD cohort, predicted ventilation maps were qualitatively and quantitatively related to ground-truth MRI ventilation, and both maps were related to important patient lung function and quality-of-life measures. This study is the first to demonstrate the feasibility of predicting hyperpolarized MRI-based ventilation from single-volume, breath-hold thoracic CT, which has potential to translate pulmonary ventilation information to widely available thoracic CT imaging

Image analysis techniques for classification of pulmonary disease in cattle

Histologic analysis of tissue samples is often a critical step in the diagnosis of disease. However, this type of assessment is inherently subjective, and consequently a high degree of variability may occur between results produced by different pathologists. Histologic analysis is also a very time-consuming task for pathologists. Computer-based quantitative analysis of tissue samples shows promise for both reducing the subjectivity of traditional manual tissue assessments, as well as potentially reducing the time required to analyze each sample. The objective of this thesis project was to investigate image processing techniques and to develop software which could be used as a diagnostic aid in pathology assessments of cattle lung tissue samples. The software examines digital images of tissue samples, identifying and highlighting the presence of a set of features that indicate disease, and that can be used to distinguish various pulmonary diseases from one another. The output of the software is a series of segmented images with relevant disease indicators highlighted, and measurements quantifying the occurrence of these features within the tissue samples. Results of the software analysis of a set of 50 cattle lung tissue samples were compared to the detailed manual analysis of these samples by a pathology expert.The combination of image analysis techniques implemented in the thesis software shows potential. Detection of each of the disease indicators is successful to some extent, and in some cases the analysis results are extremely good. There is a large difference in accuracy rates for identification of the set of disease indicators, however, with sensitivity values ranging from a high of 94.8% to a low of 22.6%. This wide variation in result scores is partially due to limitations of the methodology used to determine accuracy

Evaluation of strategies for reducing the burden of COPD in the UK using Bayesian methods

Chronic obstructive pulmonary disease (COPD) is responsible for 5.3% of all deaths and 1.7% of all hospital admissions in the UK. This thesis focuses on strategies to reduce COPD burden by targeting three aspects across the public healthcare system: prevention, emergency treatment, and long-term management. Analyses were performed in a Bayesian framework to exploit its flexibility in modelling uncertainty and the incorporation of prior knowledge. First, I assessed whether communication of personalised disease risk in primary care is an effective smoking cessation intervention, using cost-effectiveness and value of information analyses based on various data sources across the literature. The odds ratio for the effectiveness of communication of personalised disease risk was 1.48 (95%CrI:0.91-2.26). While I found a probability of cost-effectiveness of about 90%, further research up to a maximum of £27 million is justified to reduce the uncertainty around this estimate. Secondly, I assessed whether case ascertainment affects the detection of poorly performing hospital trusts in the treatment of acute exacerbation of COPD (AECOPD) in secondary care, using data from the National Asthma and COPD Audit Programme. Case ascertainment was associated with 30-day mortality (OR:1.74; 1.25-2.41) and adjusting for it impacted the findings, with 5 trusts becoming outliers and 2 trusts no longer classified as outliers. Finally, using general practice data from Clinical Practice Research Datalink, I assessed whether new guidelines suggesting triple therapy (long-acting beta-2 agonists, LABA + long-acting muscarinic antagonists, LAMA + inhaled corticosteroids, ICS) for the treatment of those with poorly-controlled COPD on LABA+LAMA dual therapy improves disease outcomes. Triple therapy was not associated with severe AECOPD (IRR:1.00; 0.93-1.07) or mortality (IRR:0.95; 0.86-1.06), but was associated with increased risk of pneumonia (IRR:1.19; 1.05-1.35). This thesis applied sophisticated Bayesian methods to increase understanding of how COPD burden could be reduced in different areas of the public healthcare system.Open Acces

Mobile Health Technologies

Mobile Health Technologies, also known as mHealth technologies, have emerged, amongst healthcare providers, as the ultimate Technologies-of-Choice for the 21st century in delivering not only transformative change in healthcare delivery, but also critical health information to different communities of practice in integrated healthcare information systems. mHealth technologies nurture seamless platforms and pragmatic tools for managing pertinent health information across the continuum of different healthcare providers. mHealth technologies commonly utilize mobile medical devices, monitoring and wireless devices, and/or telemedicine in healthcare delivery and health research. Today, mHealth technologies provide opportunities to record and monitor conditions of patients with chronic diseases such as asthma, Chronic Obstructive Pulmonary Diseases (COPD) and diabetes mellitus. The intent of this book is to enlighten readers about the theories and applications of mHealth technologies in the healthcare domain

Immunological and genetic determinants of pulmonary outcome in school aged children

Background: The prevalence of respiratory disorders in children has steadily increased over the past decades to such an extent that asthma is now the most common chronic disease of childhood. Childhood asthma resembles a complex syndrome rather than a single disease, and includes many wheeze phenotypes, making its diagnosis challenging. Most likely, it is not a single risk factor that determines whether a child develops asthma, but several risk factors (e.g. environmental, immunological, genetic, onset of respiratory symptoms) that each make small contributions to the development of the disease. Already infancy, lung function tests are available to assess airway disease. These tests are predominantly used in patients with Cystic Fibrosis (CF), for whom preservation of normal lung function is crucial. Despite recent advances in lung function testing, several methodological issues remain unanswered. Higher quality tests are required in order to effectively study the various risk factors involved in the development of complex airway diseases Aim: The first aim was to describe methodological issues during infant lung function testing in order to improve their quality. The second aim was to study different risk factors for asthma development, and to investigate their association with respiratory diseases during childhood. Methods: The study was conducted within the prospective Basel-Bern infant lung development (BILD) cohort, a population-based cohort of unselected infants of Central-European origin. The survey collects prenatal data via standardized interviews and cord blood samples for the assessment of immunological and genetic information. During the first year of life, research nurses call the parents weekly to assess the occurrence of respiratory symptoms. Pulmonary function tests, as well as measurement of fractional exhaled nitric oxide (FeNO) to assess airway inflammation, are completed at 5 weeks of age, and again at 6 years of age during follow-up. Results: We provided specific recommendations on how to improve outcomes from infant lung measurements. Furthermore, we measured airway obstruction using the interrupter technique (Rint) in unsedated infants shortly after birth, and were able to show that measurements were feasible but had a high variability. We compared Rint between term and preterm infants, and found that Rint was higher, and variability of Rint lower, in term-born infants. We assessed FeNO in healthy newborn infants, and in infants with CF. FeNO at birth had no predictive value for asthma development at school age. In CF patients, FeNO at birth was lower compared to matched healthy controls. We could also show that polymorphisms in the chitinase 3-like 1 (CHI3L1) gene encoding YKl-40 were associated with asthma at 6 years. There was some indication that increased YKL-40 levels at birth may also be involved in the development of airway disease. We also developed a novel method to characterize the time series of prospectively assessed respiratory symptom scores during infancy. This method assesses symptom dynamics in an observer-independent manner. Using this method, we were able to identify a high-risk phenotype, which was predominantly male, and contained more infants exposed to maternal asthma, and environmental tobacco smoke. This phenotype was also at increased risk for asthma and atopy at school age. Conclusions: Infant lung function is useful to study airway disease at an early age, and outcomes can be improved by applying minimal changes in analyses algorithms. Assessment of airway obstruction in infants is feasible, but measurements require careful interpretation due to the high variability. We found some indication that FeNO levels early in life are determined by environmental factors and the child’s genetic profile. In CF patients, FeNO after birth was associated with the severity of the genetic mutation. In healthy infants, FeNO levels early in life seem to be influenced by environmental exposures. Our findings contribute additional, relevant knowledge on asthma risk factors and their association with respiratory symptoms from birth through school age. We found associations between genetics and the immunological status at birth with asthma at school age. The development of asthma may also depend on respiratory symptoms early in life. We could show that the pattern of symptom deterioration and recovery during the first year of life determines whether or not a child has persistent wheezing until school age

Algoritmos de procesado de señal basados en Non-negative Matrix Factorization aplicados a la separación, detección y clasificación de sibilancias en señales de audio respiratorias monocanal

La auscultación es el primer examen clínico que un médico lleva a cabo para evaluar el estado del sistema respiratorio, debido a que es un método no invasivo, de bajo coste, fácil de realizar y seguro para el paciente. Sin embargo, el diagnóstico que se deriva de la auscultación sigue siendo un diagnóstico subjetivo que se encuentra condicionado a la habilidad, experiencia y entrenamiento de cada médico en la escucha e interpretación de las señales de audio respiratorias. En consecuencia, se producen un alto porcentaje de diagnósticos erróneos que ponen en riesgo la salud de los pacientes e incrementan el coste asociado a los centros de salud. Esta Tesis propone nuevos métodos basados en Non-negative Matrix Factorization aplicados a la separación, detección y clasificación de sonidos sibilantes para proporcionar una vía de información complementaria al médico que ayude a mejorar la fiabilidad del diagnóstico emitido por el especialista. Auscultation is the first clinical examination that a physician performs to evaluate the condition of the respiratory system, because it is a non-invasive, low-cost, easy-to-perform and safe method for the patient. However, the diagnosis derived from auscultation remains a subjective diagnosis that is conditioned by the ability, experience and training of each physician in the listening and interpretation of respiratory audio signals. As a result, a high percentage of misdiagnoses are produced that endanger the health of patients and increase the cost associated with health centres. This Thesis proposes new methods based on Non-negative Matrix Factorization applied to separation, detection and classification of wheezing sounds in order to provide a complementary information pathway to the physician that helps to improve the reliability of the diagnosis made by the doctor.Tesis Univ. Jaén. Departamento INGENIERÍA DE TELECOMUNICACIÓ

Approche translationnelle du remodelage bronchique dans la broncho-pneumopathie chronique obstructive et l’asthme

Airway remodeling groups pathophysiological entities such as smooth musclehypertrophy in asthma or increase bronchial thickness due to infiltration of inflammatory cellsand fibrosis in COPD. These remodeling is correlated with the functional obstruction andtherefore with the severity of these diseases. The bronchial or lung biopsies analysis allowsto study this phenomenon which, after understanding, is an interesting therapeutic target.The first article is a review of indications of bronchoscopy in critically ill patients. The secondstudy showed an increase in blood fibrocytes during severe exacerbation of COPD patientand a correlation between their rate and the risk of patient death. CXCR4 signaling pathwayseems to be involved in the fibrocyte recruitment. The third study seeks to explore thelocation and characteristics of intra-pulmonary fibrocytes in stable COPD patients. The fourthstudy has shown, in vivo, that gallopamil, a calcium channel blocker, could reduce airwaysmooth muscle size in severe asthmatic patient by targeting mitochondrial biogenesis. Thiscould make it an interesting therapeutic weapon and totally innovative. The last study hasisolated a non-severe asthma phenotype with "increased bronchial smooth muscle," whichpresents an increased risk of exacerbation and a suboptimal control of their asthma. Themitochondria appear to play a key role as in severe asthma.Le remodelage bronchique regroupe des entités physiopaphologiques commel’hypertrophie musculaire lisse dans l’asthme ou l’augmentation d’épaisseur bronchique surl’infiltration de cellules inflammatoires et l’accumulation de fibrose dans la BPCO. Cesremodelages sont corrélés à l’obstruction fonctionnelle et donc à la sévèrité de ces maladies.L’analyse de biopsies bronchique ou pulmonaire permet d’étudier ce phénoméne qui, aprèsune meilleure compréhension, est une cible thérapeutique intérressante. Le premier articleest une revue d’indications de bronchoscopie chez les patients de réanimation. La deuxièmeétude a montré une augmentation des fibrocytes sanguins au cours d’exacerbation sévèrede patient BPCO et une corrélation entre leur taux et le risque de décès du patient. La voiede signalisation du CXCR4 semble impliquée dans ce recrutement. La troisième étudecherche à explorer la localisation et les caractéristiques intra-pulmonaires des fibrocyteschez le patient BPCO à l’état stable. La quatrième étude a montré, in vivo, que le gallopamil,un inhibiteur calcique, pouvait diminuer la taille de muscle lisse bronchique de patientasthmatique sévère en ciblant la biogenèse mitochondriale. Ceci pourrait en faire une armethérapeutique interressante et totalement novatrice. La dernière étude a permis d’isoler unphénotype de patient asthmatique non sévère à « muscle lisse bronchique augmenté » quiprésente un risque accru d’exacerbation et de contrôle non optimal de leur asthme. Lesmitochondries semblent jouer un rôle clé comme dans l’asthme sévère