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The imaging evaluation of the abdomen is of crucial importance for every radiologist. In addition to ultrasound, conventional radiographs and contrast-enhanced computed tomography (CT) are the most common imaging procedures in the abdominal region. Numerous pathognomonic signs should be known in this context by every radiologist. Radiographs of the abdomen are an often used first step in radiologic imaging, while CT examinations are carried out for further differentiation, in oncological settings and in time-critical emergency situations. A fast and clear assignment of these signs to a specific disease is the basis for a correct diagnosis. This pictorial review describes the most common pathognomonic signs in abdominal imaging. The knowledge of these pictograms is therefore essential for radiologists interested in abdominal medicine and should also be addressed in training and further education.

Rationale and Objectives: Selecting the optimal phase for coronary artery evaluation can be challenging, especially at higher heart rates, given that the optimal phase may differ for each of the coronary arteries. This study aimed to evaluate a novel vessel-specific algorithm which automatically outputs the minimum motion phase per coronary artery., Materials and Methods: The study included 44 patients who underwent 256-slice cardiac computed tomography for evaluation of chest pain. End-systolic and mid-diastolic minimal motion phases were automatically calculated by a previously validated global motion algorithm and by a new vessel-specific algorithm which calculates the minimum motion for each of the three main coronary arteries, separately. Two readers blindly evaluated all coronary segments for image quality. Median scores per coronary artery were compared by the Wilcoxon signed rank test., Results: The variation, per patient, between the optimal phases of the three coronary arteries was 5.0 ± 4.5% (1%-22%) for end systole and 4.8 ± 4.1% (0%-19%) for mid diastole. The mean image quality scores per coronary artery were 4.0 ± 0.61 for the vessel-specific approach and 3.80 ± 0.69 for the global phase selection (P < .001). Overall, 46 of 122 arteries had a better score with the vessel-specific approach and five with the standard global approach. Interreader agreement was substantial (k = 0.72)., Conclusions: This study has shown that multiple phases are required to ensure optimal image quality for all three coronary arteries and that a vessel-specific phase selection algorithm achieves superior results to the standard global approach., (Copyright © 2015 AUR. Published by Elsevier Inc. All rights reserved.)

To assess image quality and radiation exposure with prospectively gated axial CT coronary angiography (PGA) compared to retrospectively gated helical techniques (RGH). Forty patients with suspected coronary artery disease (CAD) and a stable heart rate below 65 bpm underwent CT coronary angiography (CTCA) using a 64-channel CT system. The patient cohort consisted of 20 consecutive patients examined using a PGA technique and 20 patients examined using a standard RGH technique. Both groups were matched demographically according to age, gender, body mass index, and heart rate. For both groups, two independent observers assessed image quality for all coronary segments on an ordinal scale from 1 (nonassessable) to 5 (excellent quality). Image quality and radiation exposure were compared between patient groups. There were no significant differences in vessel-based image quality between the two groups (P > 0.05). Mean (+/- SD) effective radiation exposure in the PGA group was 3.7 +/- 0.8 mSv compared to 18.9 +/- 3.8 mSv in the RGH group without ECG-based tube current modulation (P < 0.001). Preliminary experience shows PGA technique to be a promising approach for CTCA resulting in a substantial reduction in radiation exposure with image quality comparable to that of standard RGH technique.

The objective of this study is to evaluate multidetector CT (MDCT) in detecting and characterizing anomalous coronary arteries. Forty-four patients with anomalies of the coronaries were selected from a total of 1758 individuals examined with ECG-gated 4- and 16-row MDCT including thinMIP, MPR and VRT post-processing. Twenty-eight patients showed origin and course anomalies of the central coronary segments, and in this subgroup 13 were judged as "malignant" because of interarterial courses between the aortic root and the pulmonary trunk, either of the right coronary artery (n=11) or the left coronary artery (n=2). Twelve non-hemodynamic anomalies were found, affecting the coronary origins only (n=10) or the peripheral vessels courses (n=2). Four arteriovenous fistulas were present, all of them with complex arterial feeders. Regardless of vessel anatomy, coronary opacification was always possible by means of the systemic contrast agent, and the aberrant coronary arteries were visualized synoptically in direct relation to the great mediastinal vessels. In contrast to MDCT, selective cannulation and final diagnosis was possible in only 11 of the 20 catheter angiograms performed (accuracy of 55.0%). In conclusion, its non-invasiveness and precise visualization makes MDCT the standard of reference for evaluating anomalous coronary arteries.