TITLE:
Evaluation of a Reduced Contrast Media Protocol in Thoracoabdominal Aortic High Pitch CT-Angiography
AUTHORS:
Sebastian D. Reinartz, Darius Karnitzschky, Christiane K. Kuhl, Andreas H. Mahnken
KEYWORDS:
Aortic Computed Tomography, Angiography, Radiologic Technology
JOURNAL NAME:
Open Journal of Radiology,
Vol.5 No.4,
December
4,
2015
ABSTRACT: Objectives: The aim is to evaluate contrast enhancement and density distribution in non-ECG-synchronized high-pitch aortoiliacal CT-angiography. Methods: 84 patients underwent clinically indicated thoracoabdominal CTA between February 2011 and May 2012 using high-pitch technique for arterial phase and an individually tailored contrast-media protocol depending on weight-class and scan duration. Standardized measurement of intravascular density is performed and accessed by multi plane reformations (MPR) orthogradly to vessels centerline. Results for 1.5 cm slices are statistically evaluated on per slice, per vessel segment ascending aortic, aortic arch, descending and abdominal aorta, right and left iliacal artery (common and external) and per patient level, regarding left-ventricular function and renal impairment. Results: In mean 53.1 ± 7.4 ml contrast-medium is administered for aortoiliacal examination. 4841 slices with mean density 280.0 ± 63 HU are analyzed. In 84.2% (n = 4074), diagnostic quality is delivered. Regarding vessel segments, mean enhancement scored ≥ 255.5 except weight-class 5. Adjusted to homogeneity of bolus by excluding examinations with failed bolus triggering (14%), weight-class 1 to 3 provides 100% to 75% entirely diagnostic datasets, where amount is inadequate in weight-classes 4 (62%) and 5 (2%). Conclusions: CM protocol produces moderate but diagnostic vessel enhancement with little CM (mean = 50.7 ± 6 ml) in patients smaller than 86 kg (weight-class 1 to 3) independently to left ventricular or renal function. Failure rate requires precise bolus triggering.