Observer Performance for Detection of Pulmonary Nodules at Chest CT over a Large Range of Radiation Dose Levels.

Background There is a wide variation in radiation dose levels that can be used with chest CT in order to detect indeterminate pulmonary nodules. Purpose To compare the performance of lower-radiation-dose chest CT with that of routine dose in the detection of indeterminate pulmonary nodules 5 mm or greater. Materials and Methods In this retrospective study, CT projection data from 83 routine-dose chest CT examinations performed in 83 patients (120 kV, 70 quality reference mAs [QRM]) were collected between November 2013 and April 2014.

The utility of chest computed tomography (CT) and RT-PCR screening of asymptomatic patients for SARS-CoV-2 prior to semiurgent or urgent hospital procedures.

Objective: Presently, evidence guiding clinicians on the optimal approach to safely screen patients for coronavirus disease 2019 (COVID-19) to a nonemergent hospital procedure is scarce. In this report, we describe our experience in screening for SARS-CoV-2 prior to semiurgent and urgent hospital procedures.

Design: Retrospective case series.

Prospective Pilot Evaluation of Radiologists and Computer-aided Pulmonary Nodule Detection on Ultra-low-Dose CT With Tin Filtration.

Purpose: The aim of this study was to evaluate the ability of computer-aided detection (CAD) and human readers to detect pulmonary nodules ≥5 mm using 100 kV ultra-low-dose computed tomography (ULDCT) utilizing a tin filter.

Materials And Methods: After informed consent, 55 patients prospectively underwent standard-dose chest CT (SDCT) using 120 kV followed by ULDCT using 100 kV/tin. Reference nodules ≥5 mm were identified by a thoracic radiologist using SDCT.

The breadth of the diaphragm: updates in embryogenesis and role of imaging.

The diaphragm is an unique skeletal muscle separating the thoracic and abdominal cavities with a primary function of enabling respiration. When abnormal, whether by congenital or acquired means, the consequences for patients can be severe. Abnormalities that affect the diaphragm are often first detected on chest radiographs as an alteration in position or shape.

Solving a Mystery . . . 8 Years Later.

Erdheim-Chester disease is a rare non-Langerhans cell histiocytosis with multisystem involvement and insidious symptoms. In this article, we describe an interesting case of Erdheim-Chester disease that was eventually diagnosed 8 years after symptoms initially started.

Evaluation of a projection-domain lung nodule insertion technique in thoracic computed tomography.

Task-based assessment of computed tomography (CT) image quality requires a large number of cases with ground truth. Prospective case acquisition can be time-consuming. Inserting lesions into existing cases to simulate positive cases is a promising alternative.

Evaluation of a projection-domain lung nodule insertion technique in thoracic CT.

Task-based assessment of computed tomography (CT) image quality requires a large number of cases with ground truth. Inserting lesions into existing cases to simulate positive cases is a promising alternative approach. The aim of this study was to evaluate a recently-developed raw-data based lesion insertion technique in thoracic CT.

Evaluation of suspected aspirated beverage can pull tab: radiographs may not be enough.

A 67-year-old male presented to the emergency department with concern for accidental aspiration of an aluminum beverage can pull tab. Neck and chest radiographs did not reveal an aspirated foreign body. Despite ongoing complaint of dysgeusia and adamancy of aspiration by the patient, he was discharged to home without recommendation for further follow-up.

Measurement of caval blood flow with MRI during respiratory maneuvers: implications for vascular contrast opacification on pulmonary CT angiographic studies.

Objective: Transient interruption of the contrast bolus has been described as a physiologic artifact that can sometimes result in poor opacification of the pulmonary arteries on pulmonary CT angiographic studies. To better understand the mechanism underlying this artifact, we used velocity-encoded cine MRI to measure flow in the inferior vena cava (IVC) and superior vena cava (SVC) during respiratory maneuvers.

Subjects And Methods: Quantitative measurements of SVC and IVC flow per R-R interval were performed on 10 healthy volunteers (six men, four women; median age, 30 years; range, 25-55 years) with a retrospectively ECG-gated velocity-encoded gradient-echo cine sequence on a 1.

Coronary computed tomographic angiography: current and future uses.

Coronary computed tomographic angiography (CCTA) is a direct but minimally invasive method of visualizing coronary arteries. Acceptable indications for this technique include the assessment of suspected or known coronary artery anomalies, the evaluation of chest pain syndromes in patients with non diagnostic stress tests or who are unable to exercise, and exclusion of an ischemic etiology in patients with unexplained left ventricular dysfunction. Assessment of coronary stents with a diameter of <3.

Computed tomographic angiography of the coronary arteries: techniques and applications.

Computed tomographic coronary angiography (CT-CA) is a direct but minimally invasive method of visualizing coronary arteries. Multidetector-row computed tomography (MDCT) is currently the CT modality most commonly used for coronary artery imaging. MDCT has been successfully used to detect stenoses in coronary arteries and coronary artery bypass grafts and to assess congenital coronary anomalies.

Assessment of left ventricular myocardial function using 16-slice multidetector-row computed tomography: comparison with magnetic resonance imaging and echocardiography.

Objective: To assess functional parameters using multidetector-row computed tomography (MDCT) and echocardiography and to compare the results with magnetic resonance imaging (MRI).

Materials And Methods: End-diastolic-volume (EDV), end-systolic-volume (ESV), stroke-volume (SV), ejection-fraction (EF), and myocardial mass (MM) were calculated based on CT data sets from 52 patients. Echocardiography was performed in 24 of the 52 patients.

Effect of acquisition technique on radiation dose and image quality in multidetector row computed tomography coronary angiography with submillimeter collimation.

Rationale And Objectives: We sought to examine effects of tube voltage and current on radiation dose and image quality for minimally invasive coronary angiography with a 16-slice multidetector row computed tomography (MDCT) scanner.

Materials And Methods: We scanned the phantom used in the American College of Radiology Computed Tomography Accreditation Program at tube voltages of 80 and 120 kVp at 550, 650, and 750 mAseff, with and without a reduction in radiation dose by electrocardiographically (ECG) controlled tube current modulation (ECG pulsing).

Results: Without ECG pulsing, the effective dose was 3 to 13 mSv.

Techniques and parameters for estimating radiation exposure and dose in cardiac computed tomography.

With increasing clinical use of cardiac CT imaging it is important that all health care providers referring for or administering such examinations are familiar with the concepts and values of radiation dosimetry in CT as well as with the basic principles of radiation protection. There are important technical differences pertinent to radiation dose between the CT scanner types that are currently being used for imaging of the heart and coronary arteries. As a result of these differences, the radiation dose typically is higher when a cardiac examination is performed with multidetector-row CT (MDCT) than when it is performed with electron beam CT.

ECG-gated 16-MDCT of the coronary arteries: assessment of image quality and accuracy in detecting stenoses.

Objective: The aim of this study was to investigate image quality and diagnostic accuracy in detecting coronary artery lesions using a 16-MDCT scanner.

Materials And Methods: Thirty-seven patients (28 men, nine women) underwent unenhanced helical CT and MDCT angiography of the coronary arteries. After patients received oral beta-blocker medication, CT scans were obtained during a single breath-hold with a 16-MDCT scanner using ECG-gating (0.

Imaging of congenital coronary anomalies with multislice computed tomography.

Objective: To describe a single-center experience of using retrospectively gated multislice computed tomographic (MSCT) coronary angiography for imaging congenital coronary anomalies.

Patients And Methods: We retrospectively reviewed the clinical information and imaging studies for 9 patients diagnosed as having congenital coronary anomalies on invasive, selective coronary angiography between February 2001 and October 2003 at the Mayo Clinic in Jacksonville, Fla. Two experienced observers classified by consensus the origin and proximal course of the abnormal coronary arteries as seen on MSCT.

The ratio of flow in the superior and inferior caval veins after construction of a bidirectional cavopulmonary anastomosis in children.

In patients who have undergone a superior cavopulmonary anastomosis, the superior caval venous flow provides the only, or the most important, pulmonary blood supply, while the inferior caval venous blood is not oxygenated, being mixed with the pulmonary venous blood before entering the systemic circulation. In healthy children, the contribution of superior caval venous flow to total cardiac output has been shown to decrease during growth. Patients who have undergone a superior cavopulmonary anastomosis, however, often have a higher oxygen saturation than predicted by the age-matched ratio of superior to inferior caval venous flows.

Coronary artery imaging with real-time navigator three-dimensional turbo-field-echo MR coronary angiography: initial experience.

Purpose: To examine the value of a commercially available three-dimensional (3D) real-time navigator magnetic resonance (MR) coronary angiographic examination for detection of significant coronary artery stenoses, with conventional coronary angiography as the standard of reference.

Materials And Methods: Twenty-one patients underwent 3D navigator MR coronary angiography immediately before catheterization. Two observers independently graded image quality on a scale from 1 (unreadable) to 5 (excellent), quantified coronary artery visualization, and evaluated the presence of significant (ie, >50% narrowing) stenoses.

Image quality in a standardized algorithm for minimally invasive coronary angiography with multislice spiral computed tomography.

Purpose: To report our experience with a standardized approach to pharmacologic heart rate control and image postprocessing for computed tomographic coronary angiography (CTCA) with multislice computed tomography (MSCT).

Method: Two experienced observers used transaxial tomograms and maximum-intensity projections to classify coronary segments (12 per patient, 135 consecutive patients) for degree of stenosis. One factor affecting image quality was identified for each segment that could not be assessed.

Evaluation of reconstruction windows for multislice computed tomography in quantification of coronary calcium.

Rationale And Objectives: To search for an optimum reconstruction window in retrospectively gated multislice computed tomography (MSCT) for quantification of coronary calcium.

Materials And Methods: Coronary calcium quantified was examined as Agatston and volume scores by two experienced observers at 10 time points across the R-R interval of the electrocardiogram in 42 patients. A combination of statistical approaches was used to evaluate the distributions of minimum and maximum scores and of interobserver variability for both scoring methods across the cardiac cycle.

Non-invasive coronary angiography with high resolution multidetector-row computed tomography. Results in 102 patients.

Aims: A new generation of multidetector-row CT (MDCT) scanners allows complete coronary coverage using retrospective ECG gating and 1mm slices. The purpose of this study was to investigate the potential of high resolution MDCT angiography with retrospective gating for detection of coronary artery stenoses.

Methods And Results: A total of 102 patients underwent both conventional and MDCT coronary angiography.

Reproducibility and accuracy of coronary calcium measurements with multi-detector row versus electron-beam CT.

Purpose: To methodically evaluate the reproducibility and accuracy of coronary arterial calcification measurements by using spiral multi-detector row and electron-beam computed tomography (CT) with a beating heart phantom.

Materials And Methods: A phantom was built to mimic a beating heart with coronary arteries and calcified plaques. The simulated vessels moved in a pattern similar to that of a beating heart.