Revival of monophasic contrast injection protocols: superiority of a monophasic injection protocol compared to a biphasic injection protocol in high-pitch CT angiography

Abstract

Background

Biphasic injection protocols are frequently used because they yield homogenous contrast enhancement. We hypothesize that with faster scanners and shorter scan times, biphasic injection protocols are no longer necessary.

Purpose

To evaluate whether a monophasic injection protocol is equivalent to a biphasic protocol in terms of contrast enhancement and homogeneity.

Material and Methods

Repeated high-pitch CTA (pitch 3) and conventional standard-pitch computed tomography angiography (CTA) (pitch 1.2) from the cervical region to the symphysis was performed in seven beagles (11.2 ± 2.5 kg) in a cross-over study design. Arterial contrast enhancement was measured along the z-axis in the ascending, descending, and abdominal aorta and the iliac arteries. The z-axis is the longitudinal axis of the human body and at the same time the direction in which the CT table is moving. The data were analyzed using repeated measures ANOVA with a post-hoc t-test and visual assessment of the scans.

Results

In high-pitch CTA, monophasic injection protocols were superior to biphasic injection protocols in enhancement levels (P < 0.05) and enhancement homogeneity along the z-axis (P < 0.05). In conventional CTA, enhancement levels did not differ. Contrast homogeneity was better for biphasic protocols.

Conclusion

High-pitch CTA monophasic injection protocols are superior to biphasic injection protocols, due to a higher and more homogeneous contrast enhancement with the same amount of contrast medium used.

Keywords

Computed tomography angiography (CTA)contrast agents image manipulation/reconstruction aorta animal investigations

Get full access to this article

View all access options for this article.

References

Cornea

McCullough

Mitsumori

. Enhancement of the pulmonary arteries and thoracic aorta: comparison of a biphasic contrast injection and fixed delay protocol with a monophasic injection and a timing bolus protocol. Emerg Radiol 2015; 22: 231–237.

Xue

Zhang

Kligerman

. Individually optimized uniform contrast enhancement in CT angiography for the diagnosis of pulmonary thromboembolic disease–a simulation study. Med Phys 2013; 40: 121906–121906.

Tognolini

Arellano

CSW

Marfori

. Comprehensive low-dose imaging of carotid and coronary arteries with a single-injection dual-source CT angiography protocol. Clin Radiol 2014; 69: 246–253.

Kligerman

White

. Image quality and feasibility of an ultralow-dose high-pitch helical triple-rule-out computed tomography angiography acquired in the caudocranial direction. J Thorac Imaging 2014; 29: 50–59.5.

Haidary

Bis

Vrachliotis

. Enhancement performance of a 64-slice triple rule-out protocol vs 16-slice and 10-slice multidetector CT-angiography protocols for evaluation of aortic and pulmonary vasculature. J Comput Assist Tomogr 2007; 31: 917–923.

Eisa

Brauweiler

Peetz

. Optical tracking of contrast medium bolus to optimize bolus shape and timing in dynamic computed tomography. Phys Med Biol 2012; 57: N173–182.

Bae

. Intravenous contrast medium administration and scan timing at CT: considerations and approaches. Radiology 2010; 226: 32–61.

Lenhard

Frisk

Lengsfeld

. The effect of iodinated contrast agent properties on renal kinetics and oxygenation. Invest Radiol 2013; 48: 175–182.

Adibi

Shahbazi

. Automatic bolus tracking versus fixed time-delay technique in biphasic multidetector computed tomography of the abdomen. Iran J Radiol 2014; 11: 4617–4617.

10.

Roberts

Benamore

Benbow

. Post-mortem imaging as an alternative to autopsy in the diagnosis of adult deaths: a validation study. Lancet 2012; 379: 136–142.

11.

Apitzsch

Westphal

Penzkofer

. The use of contrast-enhanced post mortem CT in the detection of cardiovascular deaths. PLoS One 2014; 9: 93101–93101.

12.

Korporaal

Mahnken

Ferda

. Quantitative evaluation of the performance of a new test bolus-based computed tomographic angiography contrast-enhancement-prediction algorithm. Invest Radiol 2015; 50: 1–8.

13.

Bae

Heiken

Brink

. Aortic and hepatic peak enhancement at CT: effect of contrast medium injection rate–pharmacokinetic analysis and experimental porcine model. Radiology 1998; 206: 455–464.

14.

Behrendt

Jost

Pietsch

. Computed tomography angiography: the effect of different chaser flow rates, volumes, and fluids on contrast enhancement. Invest Radiol 2011; 46: 271–276.

15.

Behrendt

Mahnken

Stanzel

. Intraindividual comparison of contrast media concentrations for combined abdominal and thoracic MDCT. Am J Roentgenol 2008; 191: 145–150.

16.

Fleischmann

Rubin

. Quantification of intravenously administered contrast medium transit through the peripheral arteries: implications for CT angiography. Radiology 2005; 236: 1076–1082.

17.

Fleischmann

Rubin

Bankier

. Improved uniformity of aortic enhancement with customized contrast medium injection protocols at CT angiography. Radiology 2000; 214: 363–371.

18.

Hansmann

Fink

Jost

. Impact of iodine delivery rate with varying flow rates on image quality in dual-energy CT of patients with suspected pulmonary embolism. Acad Radiol 2013; 20: 962–971.

19.

Lee

Goo

Bae

. CTA contrast enhancement of the aorta and pulmonary artery: the effect of saline chase injected at two different rates in a canine experimental model. Invest Radiol 2007; 42: 486–490.

20.

Tsuge

Kanematsu

Goshima

. Abdominal vascular and visceral parenchymal contrast enhancement in MDCT: effects of injection duration. Eur J Radiol 2011; 80: 259–264.

21.

Yanaga

Awai

Nakaura

. Effect of contrast injection protocols with dose adjusted to the estimated lean patient body weight on aortic enhancement at CT angiography. Am J Roentgenol 2009; 192: 1071–1078.

22.

Kok

Mihl

Mingels

. Influence of contrast media viscosity and temperature on injection pressure in computed tomographic angiography: a phantom study. Invest Radiol 2014; 49: 217–223.

23.

Bonelli-Sica

de la Mora-Cervantes

Diaz-Zamudio

. Dual-source 256-MDCT for diagnosis of anomalous pulmonary venous drainage in pediatric population. Am J Roentgenol 2013; 200: 163–169.

24.

Lell

Jost

Korporaal

. Optimizing contrast media injection protocols in state-of-the-art computed tomographic angiography. Invest Radiol 2015; 50: 161–167.

25.

Mahnken

Jost

Seidensticker

. Contrast timing in computed tomography: effect of different contrast media concentrations on bolus geometry. Eur J Radiol 2012; 81: 629–632.

26.

Becker

Hong

Knez

. Optimal contrast application for cardiac 4-detector-row computed tomography. Invest Radiol 2003; 38: 690–694.

27.

Anders

Baum

Gauss

. Initial experience with prospectively triggered, sequential CT coronary angiography on a 128-slice scanner. Rofo 2009; 181: 332–328.

28.

Kerl

Ravenel

Nguyen

. Right heart: split-bolus injection of diluted contrast medium for visualization at coronary CT angiography. Radiology 2008; 247: 356–364.

29.

Puippe

Winklehner

Hasenclever

. Thoraco-abdominal high-pitch dual-source CT angiography: experimental evaluation of injection protocols with an anatomical human vascular phantom. Eur J Radiol 2012; 81: 2592–2596.