Enhancement of the pancreas after single bolus injection combined with spiral scanning. A comparative study with conventional incremental scanning after biphasic contrast injection.

ABSTRACT

The combination of a rapid single bolus injection (72 ml of a 60% concentrated iodinated contrast medium) with spiral scanning versus dynamic sequential scanning with a conventional biphasic bolus injection (150 ml of 60% concentrated iodinated contrast medium) is compared. 60 patients with normal pancreatic morphology were included in this study. 30 patients were examined with dynamic sequential scanning (cycle times of 5 seconds) during a biphasic bolus injection, 30 patients were examined with spiral scanning (cycle times of 1 second) after a single uniphasic bolus injection. For both scanning techniques, mean attenuation values of the pancreas were measured before and at different time intervals after contrast injection. The difference in attenuation values of the pancreas before and after contrast injection reflects the level of contrast enhancement in both methods. The level of contrast enhancement of the pancreas after bolus injection was not statistically significantly different in spiral scanning versus in dynamic sequential scanning. In comparison with conventional scanning, spiral scanning allows to reduce the injected dose of contrast by 50% without compromising the contrast resolution.