J Cardiovasc Comput Tomogr. 2014 Nov-Dec;8(6):426-8. doi: 10.1016/j.jcct.2014.09.004. Epub 2014 Sep 16.
Schoenhagen P, Baker ME.
In this issue of the journal, 2 articles from the University of Erlangen, Germany, describe low-dose cardiac CT angiography (CTA) acquisitions using 70 kV tube voltage with a third-generation dual-source CT system. Hell et al1 evaluate feasibility, subjective image quality (IQ), and radiation dose of coronary CTA in 26 patients with suspected coronary artery disease. Prospectively triggered high-pitch spiral acquisition and image reconstruction with filtered back projection (FBP) or iterative reconstruction (IR) algorithms were used. Mean estimated effective radiation dose was 0.3 ± 0.03 mSv. Diagnostic IQ was found in 365 of 367 (FBP) and 366 of 367 (IR) segments (P = nonsignificant). IQ was rated “excellent” in 53% (FBP) and 86% (IR) segments (P = .001) and “nondiagnostic” in 2 (FBP) and 1 segment (IR; P = nonsignificant). Image noise was lower in IR vs FBP (60 ± 10 vs 74 ± 8; P < .001). Troebs et al 2 describe a 23-year-old patient presenting with suspected myocarditis. An “ultra-low” dose 2-phase CTA + myocardial perfusion acquisition (mean effective radiation dose of 0.31 and 0.12 mSv) excluded significant coronary stenosis and also identified patchy myocardial delayed enhancement indicative of myocarditis. These studies highlight recent developments in cardiovascular CT including novel indications and low-dose acquisition techniques, but also provide the opportunity to discuss potential limitations.
Full Article: http://www.sciencedirect.com/science/article/pii/S1934592514002202