Contrast medium-enhanced pulmonary CT angiography (CTA) is increasingly used as the first-line imaging test in suspected PE and is available 24 hours a day at most institutions [10][11][12][13][14]. Pulmonary CTA not only allows direct visualization of emboli but provides information regarding the status of the right heart [15,16]. In several studies, the ratio of the RV to left ventricle (LV) diameters on pulmonary CTA has been proposed as a sign for RV dysfunction [17][18][19]. Other signs have been described, including bowing of the interventricular septum and reflux of contrast medium into the inferior vena cava (IVC) [20,21]. However, a variety of different methods for the quantitative assessment of RV dysfunction on pulmonary CTA have been proposed [17][18][19][20][21][22][23][24] and the literature shows variable results for the prognostic power of pulmonary CTA signs of RV dysfunction to predict adverse outcomes. This variability may in part be explained by the somewhat subjective nature of diagnosing RV dysfunction on pulmonary CTA because formal criteria for es- AJR 2010; 194:1500-1506 0361-803X/10/1946-1500 © American Roentgen Ray Society A cute pulmonary embolism (PE) is a common disease with a 3-month mortality rate of up to 17.4% [1][2][3][4]. Even if PE is properly treated with anticoagulation, the mortality rate in hemodynamically stable patients varies from 8.1% to 15.1% [4,5]. Death is usually caused by acute right heart failure [4][5][6][7][8][9]. Acute PE increases the pressure of the pulmonary arterial system and right ventricle (RV) resulting in RV dysfunction, which may progress to right heart failure and circulatory collapse [5,6]. Patients with RV dysfunction have a higher mortality rate than those without, even if they are initially hemodynamically stable [6,7]. Thus, the presence of RV dysfunction is a marker for adverse clinical outcome in patients with acute PE [6][7][8]. Echocardiography is the most common first-line examination to diagnose the signs of RV dysfunction [6][7][8][9]. However, this test has limited off-hour availability at many institutions, and occasionally the RV may be difficult to image with the trans thoracic approach. OBJECTIVE. The purpose of our study was to determine the interobserver reproducibility of CT findings of right ventricular (RV) dysfunction in pulmonary embolism (PE). Reproducibility of CT C a r d io p u lm o n a r y I m ag i ng • O r ig i n a l R e s e a rc hMATERIALS AND METHODS. Two experienced observers independently and retrospectively evaluated pulmonary CT angiography (CTA) studies of 50 patients with acute PE for the following signs: bowing of the interventricular septum, inferior vena cava (IVC) contrast medium reflux, RV diameter (RVD)/left ventricular diameter (LVD) ratio on axial sections and four-chamber (4-CH) views, and RV volume (RVV)/left ventricular volume (LVV) ratio. Analysis used kappa statistics, Spearman's rank correlation, and Bland-Altman statistics.RESULTS. The two observers had fair to moderate agreement (κ = 0.32-0.44)...

Adenosine-stress volumetric first pass CT perfusion imaging is feasible and may enable the evaluation of qualitative and semi quantitative parameters of myocardial perfusion in a comparable fashion as MRI.

Fungal infections of the central nervous system (CNS) pose a threat to especially immunocompromised patients and their development is primarily determined by the immune status of the host. With an increasing number of organ transplants, chemotherapy, and human immunodeficiency virus infections, the number of immunocompromised patients as susceptible hosts is growing and fungal infections of the CNS are more frequently encountered. They may result in meningitis, cerebritis, abscess formation, cryptococcoma, and meningeal vasculitis with rapid disease progression and often overlapping symptoms. Although radiological characteristics are often nonspecific, unique imaging patterns can be identified through computer tomography as a first imaging modality and further refined by magnetic resonance imaging. A rapid diagnosis and the institution of the appropriate therapy are crucial in helping prevent an often fatal outcome.

Radiologists should be prepared to fully describe congenital aortic arch anomalies; recognize them on CT angiography, especially the presence or absence of vascular rings or aberrant arteries; and explain their association with the trachea and esophagus.