Congenital abnormalities of the coronary arteries are an uncommon but important cause of chest pain and, in some cases of hemodynamically significant abnormalities, sudden cardiac death. For several decades, premorbid diagnosis of coronary artery anomalies has been made with conventional angiography. However, this imaging technique has limitations due to its projectional and invasive nature. The recent development of electrocardiographically (ECG)-gated multi-detector row computed tomography (CT) allows accurate and noninvasive depiction of coronary artery anomalies of origin, course, and termination. Multi-detector row CT is superior to conventional angiography in delineating the ostial origin and proximal path of an anomalous coronary artery. Familiarity with the CT appearances of various coronary artery anomalies and an understanding of the clinical significance of these anomalies are essential in making a correct diagnosis and planning patient treatment.

Mucin hypersecretion is commonly observed in many inflammatory diseases of the respiratory tract. MUC5AC is generally recognized to be a major airway mucin because MUC5AC is highly expressed in the goblet cells of human airway epithelium. Moreover, it is regulated by various inflammatory cytokines. However, the mechanisms by which the interleukin ( Mucin hypersecretion is commonly observed in many respiratory diseases, such as rhinitis, sinusitis, otitis media, nasal allergy, chronic bronchitis, and cystic fibrosis (1-4). Eighteen types of mucin genes have been discovered to date: MUC1 (5),

established the temporality of the disease events, which was otherwise lacking in the study. The overall burden of disease (number, duration and severity of TB relapse) and respiratory morbidity in childhood [2] are other potential confounding factors that were not considered in the study. Radiologically, healed pulmonary TB can present with cicatrisation, fibro-cavitory disease, end-stage lung destruction, pulmonary calcification, bronchiectasis, trachea-bronchial stenosis etc. [3]. With such diverse and mixed presentations, combined obstructive and restrictive defects seem highly probable, but were not observed in the study. In general, asymptomatic lung function defects in patients with past TB do not require any treatment. The study would have been clinically more relevant if the authors had given the percentage of previously treated TB patients with symptomatic lung function defects, particularly airway obstruction, who were likely to utilise medical resources in future. @ERSpublications Healed pulmonary TB often presents with residual lung function defects which may require further treatment We are grateful to Aggarwal and colleagues for their interest in our paper [1]. They are correct to point out the limitations of cross-sectional studies, particularly when they rely on recalled information, and we discussed these at some length in the paper. However, evidence needs to be evaluated in the round. Not all error is biased; the outcomes (lung function) that we used were measured objectively and, as the results were not shared with the participants at the time, are unlikely to have influenced their answers to questions about a past history of tuberculosis. We agree, of course, that objective measures of tuberculosis would have been preferable, but it seems more likely that these would have reduced random error and so strengthened the current findings. We hope to add these to future investigations in the Burden of Obstructive Lung Disease (BOLD) cohort. We also discussed at some length the problem of inferring causality from cross-sectional studies when the order of events is unclear. In this case, reverse causation (low lung function causing tuberculosis) seems unlikely, but finding that the tuberculosis preceded the lung function decline would have only slightly reduced, and not excluded, the possibility of both being explained by a third, unmeasured, variable. The argument against this rests largely on the strength of the association and the failure to account for it by adjustment for other known factors. Having raised a concern over recall errors, Aggarwal and colleagues suggest we should have used time to "lung defects" after the occurrence of tuberculosis and "total burden" of disease as exposure variables. In the BOLD study, we do not have this information but it would likely be even less reliable than the information on history of tuberculosis itself. We did have information on childhood hospitalisation for respiratory disease. We did not report this in the paper, largely because of the strong possibi...

Dual-energy CT allows measurement of the degree of enhancement and detection of calcifications without additional radiation dose.

Behçet disease is a chronic, relapsing, systemic disorder of unknown etiology, characterized by recurrent oral and genital ulcers, uveitis, and other clinical manifestations in multiple organ systems. Although the diagnosis is made on the basis of the combination of typical clinical symptoms, radiologic findings of Behçet disease show characteristic features of its involvement in the gastrointestinal, neurologic, cardiovascular, and thoracic organ systems. In the gastrointestinal tract, Behçet disease may produce various types of ulcers in the esophagus, stomach, and small and large intestines, as well as deeply penetrating ulcerations in the ileocecal region, with frequently accompanying enteric fistulas. Neurologic involvement includes typical and atypical parenchymal neurobehcet disease, dural sinus thrombosis, cerebral arterial aneurysm, occlusion, dissection, and meningitis. Vascular involvement is divided into three subsets including venous occlusion, arterial occlusion, and arterial aneurysm. Cardiac manifestations include intracardiac thrombus, endomyocardial fibrosis, periaortic pseudoaneurysm, and rupture of the sinus of Valsalva. Manifestations of Behçet disease in the thorax include pulmonary arterial aneurysm, pulmonary arterial thromboembolism, thrombosis in the superior vena cava, pulmonary infarction, hemorrhage, and vasculitis of the pleura and pericardium. These various manifestations of Behçet disease respond to steroid treatment; however, one of the characteristics of Behçet disease is the high rate of complications and recurrence after surgery. Familiarity with its various radiologic and clinical characteristics is essential in making an accurate early diagnosis and for prompt treatment of patients with Behçet disease.

Institutional review board approval and written informed consent were obtained. Although xenon (Xe) ventilation CT has been introduced as a potential method with which to depict regional ventilation, quantification of Xe enhancement has been limited by the variability of lung attenuation caused by different lung volumes between scans. The purpose of this study was to assess the feasibility of Xe ventilation CT with a dual-energy technique. Dual-energy CT was performed in 12 subjects after Xe inhalation. With use of a dual-energy technique, the Xe component could be extracted without any influence from lung volume. Dynamic and static regional ventilation function can be displayed with an exact match to the thin-section CT image.

The proposed perfusion defect score had good correlation with RV/LV diameter ratio and CTA obstruction score. Therefore, acquisition of perfusion images at dual-energy CT may be helpful for assessing the severity of acute pulmonary embolism.

OBJECTIVE. The purposeofthis studywasto differentiaterupturedfrom unrupturedme diastinal teratomas using CT.MATERIALSAND METHODS. CT findingsin 17casesof surgicallyresectedmediasti nal teratomas were reviewed retrospectively. Preoperative rapture was found in seven patients during surgery. We compared the clinical symptoms and CT findings of ruptured tumors with those of unruptured tumors. On CT, we evaluated size, wall thickness, location of the mass, presence or absence of internal septation, homogeneity of the internal components of each compartment, calcification or fat within the mass, and ancillary findings in adjacent structures. RESULTS. Severesymptoms(chestpain or hemoptysis)were more commonlyfound inruptured (71%) than in unruptured tumors. All ruptured mediastinal teratomas had a tendency to display inhomogeneityof the internal components, whereas90% of unrupturedmasses showedhomogeneous densitiesof internalcomponents in eachcompartment of themass. An cillary CT findings in ruptured tumors included fat-containing masses in adjacent lung paren chyma in two patients, consolidation or atelectasis in the adjacent lung in three patients, pericardial effusionin onepatient,andpleuraleffusionin four patients. CONCLUSION.In casesof mediastinalteratoma,CT findingsof inhomogeneityof the internal components and changes in the adjacent lung parenchyma, pleura, or pericardium can be used as signs of tumor rupture. Most common primary germ-cell tu mors in the mediastinum are cystic teratomas containing ectodermal, mesodermal, and endodermal derivatives [1]. [6,7,9]. In addition, surgical management of ruptured tumors often is more complicated than that of unruptured tumors because the in ternal components of the teratoma leak into the thoracic cavity, causing inflammation and adhesion. Therefore, preoperative diagnosis of ruptured teratoma is important for deciding the appropriate time for surgery and the plan of surgical approach. The purpose of this study was to differentiate ruptured from un ruptured mediastinal teratomas on CT. Materials and MethodsWe retrospectivelystudied 17 consecutivecases Choi et al.We compared the clinical symptoms and CT features of ruptured tumors with those of unrup tured tumors. Two radiologists who were unaware of the final results analyzed the CT findings with regard to the size, wall thickness, location of the mass, presence or absence of internal septation, ho mogeneity of internal components, and calcifica tion or fat within the mass. Ancillary CT findings in adjacent lung parenchyma, pleura, or pericar dium also were analyzed. The volume of the mass was determined by measuring its length, width, and height. The maximum wall thickness of themass was measured and divided into thin and thick groups; a thin mass was defined as having a thick ness of 1â€"5 mm, and a thick mass was defined as having a thickness equal to or greater than 6 mm.To analyze the CT features, the cases of ruptured and unruptured mediastinal teratomas were inter mixed randomly. The CT scans of both groups we...