Improvement of Contrast Media Enhancement in CTA Evaluating Pulmonary Embolism by Utilizing 'Delayed' Bolus Tracking in the Descending Aorta.
BACKGROUND
As standard bolus triggering in the pulmonary trunk sometimes fails to achieve sufficient enhancement in the pulmonary arteries, the study investigates an alternative, 'delayed' position of the tracking ROI in the descending aorta.


METHODS
Retrospective analysis of 143 patients suspected of pulmonary embolism investigated with 3 different scanners (16 to 80 rows) in clinical routine. Bolus triggering with 120 hounsfield units (HU) was performed using the pulmonary trunk (n=70) or descending aorta (n=73) after application of 70 to 120 mL of contrast agent, Iomeprol 300. Student's t-test was applied to compare vascular enhancement. Additional factors were analysed by a regression analysis.


RESULTS
Positioning of the tracking ROI in the descending aorta achieved a significantly higher contrast enhancement in the pulmonary trunk with a mean increase of 63 HU (p<0.001).


CONCLUSIONS
In CTA, delayed acquisition by using the descending aorta for bolus triggering can improve the enhancement of the pulmonary trunk to investigate a pulmonary embolism. Furthermore, the scan protocol simultaneously allows to rule out aortic pathologies as an alternative cause for a similar clinical condition.
Department for Radiology and Nuclear Medicine, University of Magdeburg, Magdeburg, Germany.
Robert
R
Damm
Department for Radiology and Nuclear Medicine, University of Magdeburg, Magdeburg, Germany.
Konrad
K
Mohnike
Department for Radiology and Nuclear Medicine, University of Magdeburg, Magdeburg, Germany.
Angelos
A
Gazis
Department for Radiology and Nuclear Medicine, University of Magdeburg, Magdeburg, Germany.
Bela
B
Rogits
Department for Radiology and Nuclear Medicine, University of Magdeburg, Magdeburg, Germany.
Max
M
Seidensticker
Department for Radiology and Nuclear Medicine, University of Magdeburg, Magdeburg, Germany.
Jens
J
Ricke
Department for Radiology and Nuclear Medicine, University of Magdeburg, Magdeburg, Germany.
Maciej
M
Pech
Contrast Media; Multidetector Computed Tomography; Pulmonary Embolism
Ren Fail. 2010;32(7):796-801
20662692
AJR Am J Roentgenol. 2012 Dec;199(6):1247-51
23169715
J Thorac Imaging. 2007 May;22(2):125-9
17527114
J Thorac Imaging. 2014 Mar;29(2):107-12
24157623
Acta Radiol. 2014 Oct;55(8):932-7
24103917
Br J Radiol. 2011 May;84(1001):427-34
21045067
BMJ. 2013 Aug 20;347:f5118
23963554
Eur J Radiol. 2012 Dec;81(12):3663-8
21396792
Tech Vasc Interv Radiol. 2006 Dec;9(4):134-42
17709077
N Engl J Med. 2006 Jun 1;354(22):2317-27
16738268
Hamostaseologie. 2005 May;25(2):219-36; quiz 237-8
15945147
AJR Am J Roentgenol. 2010 Aug;195(2):W118-24
20651170