No abstract

The trial is registered at www.ClinicalTrials.gov, reference: NCT00567515.

For patients with an average heart rate less than 63 beats/min and heart rate variability less than 1.2 beats/min, dual-source CT angiography of the thoracoabdominal aorta at a high pitch of 3.2 delivers diagnostic depiction of the coronary arteries at a low radiation dose.

Purpose To compare image quality and radiation dose of high-pitch computed tomography angiography(CTA) of the aortic valve-aortic root complex with and without prospective ECG-gating compared to a retrospectively ECG-gated standard-pitch acquisition. Materials and Methods 120 patients(mean age 68 ± 13 years) were examined using a 128-slice dual-source CT system using prospectively ECG-gated high-pitch (group A; n=40), non-ECG-gated high-pitch(group B; n= 40) or retrospectively ECG-gated standard-pitch(C; n=40) acquisition techniques. Image quality of the aortic root, valve and ascending aorta including the coronary ostia was assessed by two independent readers. Image noise was measured, radiation dose estimates were calculated. Results Interobserver agreement was good(κ=0.64-0.78). Image quality was diagnostic in 38/40 patients(group A), 37/40(B) and 38/40(C) with no significant difference in number of patients with diagnostic image quality among all groups (p = 0.56). Significantly more patients showed excellent image quality in group A compared to groups B and C(each, p<0.01). Average image noise was significantly different between all groups(p<0.05). Mean radiation dose estimates in groups A and B(each; 2.4±0.3 mSv) were significantly lower compared to group C(17.5±4.4 mSv; p<0.01). Conclusion High-pitch dual-source CTA provides diagnostic image quality of the aortic valve-aortic root complex even without ECG-gating at 86% less radiation dose when compared to a standard-pitch ECG-gated acquisition.

DECT with TF and 80-140 kVp tube voltage settings significantly improves the discrimination between UA-containing and non-UA containing urinary stones as compared with DECT without using the TF on the basis of DEI. The 100/140 kVp setting with TF is associated with lower IN but demonstrates similar discrimination abilities as compared with 80/140 kVp setting without the use of the TF.

In the authors' Caucasian subjects, all or most of the sweat glands were found in the subcutaneous tissue near the border to the dermis and not in the dermis. For extremely hyperfunctioning sweat glands, the authors recommend less radical surgical methods, with the preservation of skin, based on the knowledge that most glands are localized in the subcutaneous tissue.

Dual-source CT coronary angiography with use of prospective ECG triggering performs accurately in the assessment of coronary artery disease at low radiation doses. Diagnostic accuracy remains high despite the presence of heavy calcifications but is associated with an increased rate of nondiagnostic segments.

The patency of coronary artery bypass grafts can be assessed with decreasing image quality at high HR in high-pitch prospectively ECG-synchronized thoracic 128-slice dual-source CT angiography at a low radiation dose.