Katsumi Tsujioka PhD, Presenter: Nothing to Disclose

Hiroyuki Kato, Abstract Co-Author: Nothing to Disclose

Yoshitaka Isobe, Abstract Co-Author: Nothing to Disclose

Yujiro Doi, Abstract Co-Author: Nothing to Disclose

Tetsuya Hirokawa, Abstract Co-Author: Nothing to Disclose

Akihito Watanabe, Abstract Co-Author: Nothing to Disclose

Hayato Shimomura, Abstract Co-Author: Nothing to Disclose

We have been proposing a method for determining the injection amount of contrast media (Auto Contrast Enhance Control: ACEC) through use of scanography. This method determines the injection amount of contrast media by calculating the X-ray absorption at each CT cross-section based on the scanographical data available in advance when conducting CT scan, and then estimating the CT value increase for the target organ. In this study, following the fundamental experiment using phantoms, we compared and considered the X-ray absorption index in the slice direction on the pre-obtained scanography and the CT value changes in the organ in a real-life clinical case wherein the contrast media amount was not changed.

In this study, we used a contrast CT scan case for which a certain amount of contrast media was injected rather than adjusting the injection amount according to the weight or weight excluding fat, etc. For the obtained data, X-ray absorption on the CT cross-section of the scanography and the contrast CT values of the liver were compared. And then, the amount of contrast media for raising the liver CT value up to the target CT value was calculated by simulation.

As a result of injecting the same amount of contrast media, in case the X-ray absorption on the sliced surface of the scanography was small, namely, the object is thin, the contrast CT value of the liver increased. This experiment revealed that the changes in X-ray absorption on the scanography and the contrast CT value changes show a constant curve. It was easy to determine the amount of contrast media for obtaining the target CT value based on the relation between the scanography data and the liver CT value changes, and the precision was high.

In this study, as a result of analyzing the data of quantitative injection of contrast media, it was found out that the X-ray absorption on the sliced surface of the scanography has a close relation with the rise in the contrast CT value of the liver. It was indicated that the injection amount of contrast media can be determined by utilizing the revealed relation above.

We developed an Auto Contrast Enhance Control System (ACEC). In this study, we found that ACEC has good performance for contrast enhance CT examination.

Tsujioka, K, Kato, H, Isobe, Y, Doi, Y, Hirokawa, T, Watanabe, A, Shimomura, H, Development of Automatic Contrast-enhanced Control (ACEC) for Abdominal CT Scan Using Scanography (Simulation of Injection Amount of Contrast Media Using Quantitative Contrast Media Injection Data).  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11034537.html