Keywords:
Pathology, Contrast agent-intravenous, Image manipulation / Reconstruction, CT, Pancreas
Authors:
O. R. Brook1, S. Gourtsoyianni2, A. Brook1, C. Wilcox1, B. Siewert1, V. Raptopoulos1; 1Boston, MA/US, 2Athens/GR
DOI:
10.1594/ecr2012/C-2620
Purpose
Pancreatic CTA is widely used for screening,
detection,
staging and follow up of the pancreatic cancer.
The standard protocol used in our institution involves non contrast study,
followed by pancreatic phase and portal venous phase.
This combination of contrast phases provides perfect conspicuity of pancreatic tumor,
proximity to vessels and detection of metastases.
Nevertheless,
multiple phases also cause very high levels of radiation exposure to the patients.
Our goal as radiologists is to reduce the radiation exposure,
due to the known risks of radiation exposure,
without deterioration of the image quality and most importantly maintaining diagnostic value of the CT scan.
Split bolus contrast administration is an established technique for a number of clinical indications most notably CT urography.
The contrast is injected twice,
while scanning is performed once only.
This provides dual phase images in a single scan,
for example nephrographic and excretory phase as in the case of CT urography.
We propose implementation of split bolus technique for providing pancreatic and portal venous / parenchymal phase for pancreatic CTA.
Monochromatic images acquired with spectral MDCT increase attenuation of the iodine containing tissues by using lower kVp due to increase in photoelectric absorption and reduction of the Compton scatter.
Furthermore,
it has been shown that conspicuity of the malignant pancreatic tumors is greater with 80kVp as compared to weighted average 120kVp,
as acquired on the dual-energy scanner.
The aim of current study was to evaluate the feasibility of combination of split bolus contrast injection with spectral MDCT protocol for pancreatic CTA,
compared to the standard multiphasic polychromatic MDCT scan.