Introduction of a dedicated circulation phantom for comprehensive in vitro analysis of intravascular contrast material application.
OBJECTIVE
To develop a circulation phantom with physiologic circulation parameters, including a pulmonary and a body circulation for the evaluation of intravascular contrast material (CM) application.


METHODS
The circulation phantom consists of a low-pressure venous system into which CM is injected, a pulmonary circulation, and high-pressure body circulation with an anthropometric aorta and coronary arteries. The phantom is driven by a pulsatile Harvard heart pump. Venous and arterial pressure were set to physiologic values with heart rate (60 beats/min), stroke volume (60 mL), and ratio of diastole to systole (60/40) also were within physiologic limits. CM with different iodine concentrations (300, 370, and 400 mg iodine/mL) were injected at a flow rate of 4 mL/s (iodine delivery rate: 1.2 g, 1.48 g, and 1.6 g iodine/s, respectively; total iodine load for all protocols: 36 g). Serial computed tomography scans at the level of the pulmonary artery, the ascending and the descending aorta replica were obtained. Dynamic pressure in the phantom and true injection system parameters (flow rate, injection pressure, and CM volume) was continuously monitored. Time-enhancement curves were calculated, and pulmonary and aortic peak time and enhancement were determined. Results were compared using nonparametric unpaired Wilcoxon tests.


RESULTS
The pressure in the phantom showed physiologic values for the low (mean pressure: 15 mm Hg) and high pressure part (125/75 mm Hg). Programmed injection values (flow rate, pressure, and volume) were reached for all injections. Using CM with 400 mg iodine/mL, the shortest pulmonary and aortic peak times and the highest pulmonary and aortic peak enhancement values were obtained compared with CM with 300 and 370 mg iodine/mL.


CONCLUSIONS
We developed a flow phantom with physiologic circulation parameters for measurement of contrast enhancement. The phantom is suitable for further evaluation of CM injection protocols for pulmonary and aortic enhancement.
Behrendt
Florian F
FF
Department of Diagnostic Radiology, University Hospital RWTH Aachen, Aachen, Germany. behrendt@rad.rwth-aachen.de
Bruners
Philipp
P
Kalafut
John
J
Mahnken
Andreas H
AH
Keil
Sebastian
S
Plumhans
Cedric
C
Das
Marco
M
Stanzel
Sven
S
Wildberger
Joachim E
JE
Pfeffer
Jochen
J
Günther
Rolf W
RW
Mühlenbruch
Georg
G
D000886:Anthropometry; D001011:Aorta / Q000502:physiology*; D001775:Blood Circulation / Q000502:physiology*; D003287:Contrast Media; D003331:Coronary Vessels / Q000502:physiology*; D006801:Humans; D066298:In Vitro Techniques; D019047:Phantoms, Imaging; D010865:Pilot Projects; D011651:Pulmonary Artery / Q000502:physiology*; D014057:Tomography, X-Ray Computed / Q000295:instrumentation*
D003287:Contrast Media