99 research outputs found
Computer aided diagnosis for severity assessment of pneumoconiosis using CT images
240,000 participants have a screening for diagnosis of pneumoconiosis every year in Japan. Radiograph is used for staging of severity in pneumoconiosis worldwide. This paper presents a method for quantitative assessment of severity in pneumoconiosis using both size and frequency of lung nodules that detected by thin-section CT images. This method consists of three steps. First, thoracic organs (body, ribs, spine, trachea, bronchi, lungs, heart, and pulmonary blood vessels) are segmented. Second, lung nodules that have radius over 1.5mm are detected. These steps used functions of our developed computer aided detection system of chest CT images. Third, severity in pneumoconiosis is quantified using size and frequency of lung nodules. This method was applied to nine pneumoconiosis patients. The initial results showed that proposed method can assess severity in pneumoconiosis quantitatively. This paper demonstrates effectiveness of our method in diagnosis and prognosis of pneumoconiosis in CT screening
Expert System with an Embedded Imaging Module for Diagnosing Lung Diseases
Lung diseases are one of the major causes of suffering and death in the world. Improved
survival rate could be obtained if the diseases can be detected at its early stage. Specialist
doctors with the expertise and experience to interpret medical images and diagnose
complex lung diseases are scarce. In this work, a rule-based expert system with an
embedded imaging module is developed to assist the general physicians in hospitals and
clinics to diagnose lung diseases whenever the services of specialist doctors are not
available. The rule-based expert system contains a large knowledge base of data from
various categories such as patient's personal and medical history, clinical symptoms,
clinical test results and radiological information. An imaging module is integrated into
the expert system for the enhancement of chest X-Ray images. The goal of this module is
to enhance the chest X-Ray images so that it can provide details similar to more
expensive methods such as MRl and CT scan. A new algorithm which is a modified
morphological grayscale top hat transform is introduced to increase the visibility of lung
nodules in chest X-Rays. Fuzzy inference technique is used to predict the probability of
malignancy of the nodules. The output generated by the expert system was compared
with the diagnosis made by the specialist doctors. The system is able to produce results\ud
which are similar to the diagnosis made by the doctors and is acceptable by clinical
standards
Expert System with an Embedded Imaging Module for Diagnosing Lung Diseases
Lung diseases are one of the major causes of suffering and death in the world. Improved
survival rate could be obtained if the diseases can be detected at its early stage. Specialist
doctors with the expertise and experience to interpret medical images and diagnose
complex lung diseases are scarce. In this work, a rule-based expert system with an
embedded imaging module is developed to assist the general physicians in hospitals and
clinics to diagnose lung diseases whenever the services of specialist doctors are not
available. The rule-based expert system contains a large knowledge base of data from
various categories such as patient's personal and medical history, clinical symptoms,
clinical test results and radiological information. An imaging module is integrated into
the expert system for the enhancement of chest X-Ray images. The goal of this module is
to enhance the chest X-Ray images so that it can provide details similar to more
expensive methods such as MRl and CT scan. A new algorithm which is a modified
morphological grayscale top hat transform is introduced to increase the visibility of lung
nodules in chest X-Rays. Fuzzy inference technique is used to predict the probability of
malignancy of the nodules. The output generated by the expert system was compared
with the diagnosis made by the specialist doctors. The system is able to produce results
which are similar to the diagnosis made by the doctors and is acceptable by clinical
standards
Modified Chrispin-Norman chest radiography score for cystic fibrosis: observer agreement and correlation with lung function
Contains fulltext :
96114.pdf ( ) (Closed access)OBJECTIVE: To test observer agreement and two strategies for possible improvement (consensus meeting and reference images) for the modified Chrispin-Norman score for children with cystic fibrosis (CF). METHODS: Before and after a consensus meeting and after developing reference images three observers scored sets of 25 chest radiographs from children with CF. Observer agreement was tested for line, ring, mottled and large soft shadows, for overinflation and for the composite modified Chrispin-Norman score. Correlation with lung function was assessed. RESULTS: Before the consensus meeting agreement between observers 1 and 2 was moderate-good, but with observer 3 agreement was poor-fair. Scores correlated significantly with spirometry for observers 1 and 2 (-0.72<R<-0.42, P < 0.05), but not for observer 3. Agreement with observer 3 improved after the consensus meeting. Reference images improved agreement for overinflation and mottled and large shadows and correlation with lung function, but agreement for the modified Chrispin-Norman score did not improve further. CONCLUSION: Consensus meetings and reference images improve among-observer agreement for the modified Chrispin-Norman score, but good agreement was not achieved among all observers for the modified Chrispin-Norman score and for bronchial line and ring shadows
New insights on COPD imaging via CT and MRI
Multidetector-row computed tomography (MDCT) can be used to quantify morphological features and investigate structure/function relationship in COPD. This approach allows a phenotypical definition of COPD patients, and might improve our understanding of disease pathogenesis and suggest new therapeutical options. In recent years, magnetic resonance imaging (MRI) has also become potentially suitable for the assessment of ventilation, perfusion and respiratory mechanics. This review focuses on the established clinical applications of CT, and novel CT and MRI techniques, which may prove valuable in evaluating the structural and functional damage in COPD
Serum Levels of Surfactant Proteins in Patients with Combined Pulmonary Fibrosis and Emphysema (CPFE)
Introduction Emphysema and idiopathic pulmonary fibrosis (IPF) present either per se or coexist in combined pulmonary fibrosis and emphysema (CPFE). Serum surfactant proteins (SPs) A, B, C and D levels may reflect lung damage. We evaluated serum SP levels in healthy controls, emphysema, IPF, and CPFE patients and their associations to disease severity and survival. Methods 122 consecutive patients (31 emphysema, 62 IPF, and 29 CPFE) and 25 healthy controls underwent PFTs, ABG-measurements, 6MWT and chest HRCT. Serum levels of SPs were measured. Patients were followed-up for 1-year. Results SP-A and SP-D levels differed between groups (p = 0.006 and p= 26 ng/mL) presented a weak association with reduced survival (p = 0.05). Conclusion In conclusion, serum SP-A and SP-D levels were higher where fibrosis exists or coexists and related to disease severity, suggesting that serum SPs relate to alveolar damage in fibrotic lungs and may reflect either local overproduction or overleakage. The weak association between high levels of SP-B and survival needs further validation in clinical trials
Design, tuning and performance evaluation of an automated pulmonary nodule detection system
Radiologists miss about 25-30% of all pulmonary nodules smaller than 1.0 cm. in mass screenings. A system for the automated detection of the pulmonary nodule based on that of Hallard has been designed, tuned, and tested on a 43 chest radiographs [Ballard, 1973). The goal of this system is to aid the radiologist in locating a pulmonary nodule by indicating a few sites in the radiograph that are most likely to be nodules. Computer image analysis programs that respond to specific types of anatomic features have been devised and are incorporated in a pattern recognizer, which uses linear discriminant analysis to classify the candidate nodule sites. Candidate nodule sites that are not classified as nodules are eliminated from the list of sites that are presented to the radiologist for inspection. The pattern recognizer was trained with the features from 2750 candidate nodules, which came from 37 films and another pattern recognizer was trained with the features from 402 candidate nodules from 9 films. This research demonstrates that pattern recognition techniques and procedurally driven image experts are capable of reducing the number of candidate nodule sites that a radiologist must inspect from at most 12 to at most 4 if he is to be 99% confident of having inspected any nodule detected by the system which was trained with 37 films. The radiologist must be willing to accept a film true positive rate of 88% (as opposed to a film true positive rate of 92%) for the convenience of having fewer points to inspect. These film true positive rates are derived from 37 films which contain nodules that were evaluated by the system. The particular contributions of this work lies in the implementation and testing of a spline filter, a preprocessing step, which removes background variations in the radiograph so that nodules are more visible; the development of Vascularity and Rib Experts which recognize these classes of candidate nodules; and in die implementation of the particular features that are extracted from the candidate nodule and used by the pattern classifier
Computer-aided diagnosis in chest radiography
Chest radiographs account for more than half of all radiological examinations; the chest is the mirror of health
and disease. This thesis is about techniques for computer analysis of chest radiographs. It describes methods for
texture analysis and segmenting the lung fields and rib cage in a chest film. It includes a description of an
automatic system for detecting regions with abnormal texture, that is applied to a database of images from a
tuberculosis screening program
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