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Rib Suppression in Chest Radiographs Using ICA Algorithm  [PDF]
Bilal Ahmed,Tahir Rasheed,Mohammad A. U. Khan,Abdur Rashid
Information Technology Journal , 2007,
Abstract: Chest radiographs play an important role in early diagnosis of lung cancer. Due to overlapping of the nodule with ribs and clavicles, the nodule is hard to detect in conventional chest radiographs. In this study A technique is presented based on Independent Component Analysis (ICA) for the suppression of posterior ribs and clavicles which will enhance the visibility of the nodule and will reduces the stress on automatic nodule detection module.
Standardized interpretation of paediatric chest radiographs for the diagnosis of pneumonia in epidemiological studies
Cherian,Thomas; Mulholland,E. Kim; Carlin,John B.; Ostensen,Harald; Amin,Ruhul; Campo,Margaret de; Greenberg,David; Lagos,Rosanna; Lucero,Marilla; Madhi,Shabir A.; O'Brien,Katherine L.; Obaro,Steven; Steinhoff,Mark C.; ,;
Bulletin of the World Health Organization , 2005, DOI: 10.1590/S0042-96862005000500011
Abstract: background: although radiological pneumonia is used as an outcome measure in epidemiological studies, there is considerable variability in the interpretation of chest radiographs. a standardized method for identifying radiological pneumonia would facilitate comparison of the results of vaccine trials and epidemiological studies of pneumonia. methods: a who working group developed definitions for radiological pneumonia. inter-observer variability in categorizing a set of 222 chest radiographic images was measured by comparing the readings made by 20 radiologists and clinicians with a reference reading. intra-observer variability was measured by comparing the initial readings of a randomly chosen subset of 100 radiographs with repeat readings made 8-30 days later. findings: of the 222 images, 208 were considered interpretable. the reference reading categorized 43% of these images as showing alveolar consolidation or pleural effusion (primary end-point pneumonia); the proportion thus categorized by each of the 20 readers ranged from 8% to 61%. using the reference reading as the gold standard, 14 of the 20 readers had sensitivity and specificity of > 0.70 in identifying primary end-point pneumonia; 13 out of 20 readers had a kappa index of > 0.6 compared with the reference reading. for the 92 radiographs deemed to be interpretable among the 100 images used for intra-observer variability, 19 out of 20 readers had a kappa index of > 0.6. conclusion: using standardized definitions and training, it is possible to achieve agreement in identifying radiological pneumonia, thus facilitating the comparison of results of epidemiological studies that use radiological pneumonia as an outcome.
Reading chest radiographs in the critically ill (Part II): Radiography of lung pathologies common in the ICU patient  [cached]
Khan Ali,AL-Jahdali Hamdan,AL-Ghanem S,Gouda Alaa
Annals of Thoracic Medicine , 2009,
Abstract: This is part II of two series review of reading chest radiographs in the critically ill. Conventional chest radiography remains the cornerstone of day to day management of the critically ill occasionally supplemented by computed tomography or ultrasound for specific indications. In this second review we discuss radiographic findings of cardiopulmonary disorders common in the intensive care patient and suggest guidelines for interpretation based not only on imaging but also on the pathophysiology and clinical grounds.
Interpretation of chest radiographs in both cancer and other critical care patients with acute respiratory distress syndrome  [cached]
Sema Yilmaz,Ozden Ozgur Horoz,Sureyya Soyupak,Fatih Erbey
Cukurova Medical Journal , 2013,
Abstract: Acute respiratory distress syndrome is a clinical, pathophysiological and radiographic pattern that has signs of pulmonary edema occur without elevated pulmonary venous pressures. Clinical presentation and progression of acute respiratory distress syndrome are followed by frequently ordered portable chest X-ray in critically ill patients. We evaluated chest radiographs of ten cancer and other six critical care pediatric patients. The parenchymal imaging of lung in patients with cancer was reported the same as that of other critically ill children despite underlying pathophysiological variations in our investigation. [Cukurova Med J 2013; 38(2.000): 270-273]
Automatic Detection of 2D and 3D Lung Nodules in Chest Spiral CT Scans  [PDF]
Ayman El-Baz,Ahmed Elnakib,Mohamed Abou El-Ghar,Georgy Gimel'farb,Robert Falk,Aly Farag
International Journal of Biomedical Imaging , 2013, DOI: 10.1155/2013/517632
Abstract: Automatic detection of lung nodules is an important problem in computer analysis of chest radiographs. In this paper, we propose a novel algorithm for isolating lung abnormalities (nodules) from spiral chest low-dose CT (LDCT) scans. The proposed algorithm consists of three main steps. The first step isolates the lung nodules, arteries, veins, bronchi, and bronchioles from the surrounding anatomical structures. The second step detects lung nodules using deformable 3D and 2D templates describing typical geometry and gray-level distribution within the nodules of the same type. The detection combines the normalized cross-correlation template matching and a genetic optimization algorithm. The final step eliminates the false positive nodules (FPNs) using three features that robustly define the true lung nodules. Experiments with 200?CT data sets show that the proposed approach provided comparable results with respect to the experts. 1. Introduction Lung cancer remains the leading cause of cancer-related deaths in the US. In 2012, there were approximately 229,447 new cases of lung cancer and 159,124 related deaths [1]. Early detection of lung tumors (visible on chest film as nodules) may increase the patient’s chance of survival, but detecting nodules is a complicated task. Nodules show up as relatively low-contrast white circular objects within the lung fields. The difficulty for computer-aided detection (CADe) schemes is distinguishing true nodules from (overlapping) shadows, vessels, and ribs. CADe systems for detection of lung nodules in thoracic CT generally consist of two major stages: (1) selection of the initial candidate nodules and then (2) elimination of the false positive nodules (FPNs) with preservation of the true positive nodules (TPNs). At the first stage, conformal nodule filtering or unsharp masking can enhance nodules and suppress other structures to separate the candidates from the background by simple thresholding or a multiple gray-level thresholding technique [2, 3]. To improve the separation, background trend is corrected in [4, 5] within image regions of interest. Then, a series of 3D cylindrical and spherical filters are used to detect small lung nodules from high-resolution CT images [6, 7]. Circular and semicircular nodule candidates can be detected by template matching [8–11]. However, these spherical, cylindrical, or circular assumptions are not adequate for describing the general geometry of the lesions. This is because their shape can be irregular due to the speculation or the attachments to the pleural surface (i.e.,
Exame radiográfico convencional do tórax no diagnóstico de hérnia diafragmática pós-traumática Plain chest radiographs for the diagnosis of post-traumatic diaphragmatic hernia  [cached]
Elcio Shiyoiti Hirano,Vanessa Gon?alves Silva,José Benedito Bortoto,Ricardo Hoelz de Oliveira Barros
Revista do Colégio Brasileiro de Cirurgi?es , 2012, DOI: 10.1590/s0100-69912012000400007
Abstract: OBJETIVO: Descrever as altera es do exame radiográfico de tórax em pacientes com diagnóstico de hérnia diafragmática pós-traumática (HDPT) confirmado no intraoperatório. MéTODOS: No período entre janeiro de 1990 e agosto de 2008 foram tratados 45 pacientes com HDPT. Foram analisados dados demográficos, mecanismo de trauma, altera es na radiografia convencional de tórax (Rtx), extens o e localiza o da les o do diafragma e órg os herniados. Foram descritos os achados radiográficos mais frequentes identificados por assistentes da cirurgia e da radiologia. RESULTADOS: A Rtx foi realizada em 32 pacientes, com predomínio do sexo masculino (27 casos - 84,4%) e a média das idades foi 34 anos. O mecanismo de trauma mais frequente foi o contuso (25 casos - 78,1%). O exame radiográfico de tórax apresentava altera es sugestivas de HDPT em 26 casos (81,3%). Na laparatomia exploradora constatou-se HDPT à esquerda em 28 casos (87,5%) e à direita em 4 (12,5%). O órg o herniado mais frequente foi o est mago. CONCLUS O: O estudo mostrou que o Rtx é muito útil na pesquisa inicial no diagnóstico de HDPT. A dificuldade é que as les es de diafragma, principalmente após trauma penetrante, podem passar inicialmente despercebidas, sem altera es nesse método de imagem, tornando o diagnóstico difícil. OBJECTIVE: To describe changes in the radiographic examination of the chest in patients with post-traumatic diaphragmatic hernia (PTDH) confirmed intra-operatively. METHODS: Between January 1990 and August 2008 45 patients with PTDH were treated. We analyzed demographic data, cause of injury, changes in chest radiography (CXR), extent and location of the diaphragmatic lesion and herniated organs. We described the radiographic findings most frequently identified by surgeons and radiologists. RESULTS: CXR was performed on 32 patients, predominantly male (27 cases, 84.4%) and the mean age was 34 years. The most common cause of injury was blunt trauma (25 cases, 78.1%). Radiographic examination of the chest showed changes suggestive of PTDH in 26 cases (81.3%). During exploratory laparotomy, left PTDH was found in 28 cases (87.5%) and right in four (12.5%). The most frequently herniated organ was the stomach. CONCLUSION: The study showed that CXR is very useful in the initial diagnostic approach to PTDH. The difficulty is that diaphragmatic injuries, particularly after penetrating trauma, may initially go unnoticed, and without changes in the CXR images, diagnosis is made difficult.
Utility of postintubation chest radiographs in the intensive care unit
Ramya Lotano, David Gerber, Cristina Aseron, Rocco Santarelli, Melvin Pratter
Critical Care , 2000, DOI: 10.1186/cc650
Abstract: This was a prospective study. Endotracheal intubations in an 11-bed intensive care unit and a nine-bed intermediate intensive care unit were included. After intubations were performed by an experienced critical care operator, that individual recorded demographic and procedural data, and predicted radiographic findings on a data collection sheet. Experience at intubation was stratified into four levels of lifetime experience: fewer than 10 procedures, 10-20 procedures, 20-50 procedures, and more than 50 procedures. Radiographic findings evaluated included endotracheal tube position and procedure-related complications. The postintubation chest radiograph was then reviewed and the actual findings were also recorded.A total of 101 evaluable intubations were recorded, two of which were predicted to show tube malposition. Actual radiographic findings revealed 10 malpositions, three of which were too high and seven were too low (one at the level of the carina). A single witnessed aspiration that occurred during intubation was not radiographically apparent until 24 h later. Only the tube positioned at the carina was felt to be of acute clinical significance or to place the patient at any acute risk.The incidence of endotracheal tube malposition after intubation was underestimated. However, when performed by experienced critical care personnel, acutely significant malpositions were rare (one out of 101 intubations). We conclude that, in the absence of specific pulmonary complications, endotracheal intubations performed by experienced operators may be followed by routine, rather than 'stat' chest radiographs.Endotracheal intubation is a common procedure in intensive care units (ICUs), and may be performed for numerous reasons and under varying circumstances, both elective and emergent. This procedure is performed by individuals with disparate levels of training and experience, ranging from junior residents in various specialties to anesthesiology attending physicians. It is c
N2 disease in non-small cell lung cancer patients, diagnosis and evaluation: a Turkish chest surgeon's perspective
Alper TOKER
Chinese Journal of Lung Cancer , 2008,
Abstract: Mediastinal or N2 disease is the most important factor in selecting the optimal treatment strategy in patients without distant metastasis. A direct surgical resection has not generally been accepted as a treatment modality inwhom mediastinal nodal involvement is demonstrated. Patients with lung cancer can be diagnosed as clinical N2 disease based on CT and PET-CT characteristics of the mediastinum and the clinical presentation. Invasive diagnostic modalities used in the detection of N2 disease are: mediastinoscopy, endoesophageal ultrasound guided biopsy (EUS), transbronchial needle aspiration (TBNA), endobronchial ultrasound guided biopsy (EBUS), video-assisted thoracoscopic surgery (VATS),and mediastinotomy/extended mediastinoscopy. In this article, the author discusses about invasive and noninvasive techniques on the evaluation of mediastinal disease and presents his experience on this topic.
Do pediatric intensivists and radiologists concur on the interpretation of chest radiographs?
C Robert Chambliss, Toni Petrillo, Burton L Lesnick, Kevin Sullivan
Critical Care , 1998, DOI: 10.1186/cc128
Abstract: The evaluation of 291 chest radiographs demonstrated an overall concordance rate of 82.5% (240 out of 291; P < 0.05). There was no significant difference in the ability of critical care medicine physicians to identify atelectasis, infiltrates, pleural effusions, or airleaks (P > 0.05). Support devices were correctly identified in 100% of the cases. Discordant interpretations included 20 that were clinically significant, 17 insignificant findings and 14 films over-interpreted by the PI. A chart review of the patients with discordant findings revealed only one finding that required an alteration in therapy.These findings demonstrate significant agreement between the interpretation of chest radiographs by PI and PR in selected clinical situations. These data support the current practice of the PI making therapeutic decisions based on their interpretations of chest radiographs.Chest radiographs are obtained in the pediatric intensive care unit to assess cardiopulmonary abnormalities, evaluate acute clinical deterioration, and to determine the position of invasive life support devices such as central venous catheters and endotracheal tubes. Immediate interpretation of these chest radiographs is often necessary to assess whether further diagnostic or therapeutic interventions are necessary and to determine proper position of invasive devices. The pediatric intensivists (PI) at the bedside are often the first physicians to interpret a radiograph and frequently base diagnostic and therapeutic interventions on their interpretations. With fewer than 30% of hospitals having a radiologist available in the hospitals having a radiologist available in the hospital 24 h a day [1], a formal interpretation by the radiologist is not readily available until after most acute interventions have occurred. Accurate interpretation of chest radiographs by a PI when a radiologist is not immediately available is crucial for optimum patient care. Few centers have mechanisms to determine if disc
Novel coarse-to-fine dual scale technique for tuberculosis cavity detection in chest radiographs
Tao Xu, Irene Cheng, Richard Long and Mrinal Mandal
EURASIP Journal on Image and Video Processing , 2013, DOI: 10.1186/1687-5281-2013-3
Abstract: Although many lung disease diagnostic procedures can benefit from computer-aided detection (CAD), current CAD systems are mainly designed for lung nodule detection. In this article, we focus on tuberculosis (TB) cavity detection because of its highly infectious nature. Infectious TB, such as adult-type pulmonary TB (APTB) and HIV-related TB, continues to be a public health problem of global proportion, especially in the developing countries. Cavities in the upper lung zone provide a useful cue to radiologists for potential infectious TB. However, the superimposed anatomical structures in the lung field hinder effective identification of these cavities. In order to address the deficiency of existing computer-aided TB cavity detection methods, we propose an efficient coarse-to-fine dual scale technique for cavity detection in chest radiographs. Gaussian-based matching, local binary pattern, and gradient orientation features are applied at the coarse scale, while circularity, gradient inverse coefficient of variation and Kullback–Leibler divergence measures are applied at the fine scale. Experimental results demonstrate that the proposed technique outperforms other existing techniques with respect to true cavity detection rate and segmentation accuracy.
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