Novel contrast-injection protocol for high-resolution abdominal CT-angiography: vascular visualization improvement with vasodilator.

Abstract

To evaluate the usefulness of a novel contrast-injection protocol for high-resolution abdominal computed tomography angiography (CTA) using nitroglycerin (NTG). Abdominal CTA was performed in 80 patients using two 64-detector-row CT scanners. Forty patients were examined after administration of sublingual NTG (NTG group), while 40 were examined without NTG administration (non-NTG group). Arterial phase images were acquired with maximum intensity projection and volume rendering. Reduction rates: vessel cross-sectional areas ratio of 10 cm distal to origin at the superior mesenteric artery, contrast enhancements, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were assessed. Three reviewers evaluated degree of depiction of the peripancreatic vasculature using a four-point scale (1=poor, 4=excellent). Reduction rates were significantly lower in the NTG group (P<0.001), while there were no significant differences in contrast enhancements, SNR, or CNR between groups. Visual evaluation results of the NTG group were significantly better than those of the non-NTG group (P<0.01). Abdominal CTA using NTG improved visualization of the abdominal peripheral vessels. This improved arterial view may be beneficial for preoperative evaluation of the arterial anatomy.