Cecile De Monye MD, PRESENTER: Nothing to Disclose

Abstract: HTML Purpose: To compare different volumes of contrast material with and without a bolus chaser for CT angiography of the carotid artery with a 16-slice multidetector CT scanner. Methods and Materials: 75 consecutive patients (50 male; mean age=62; range 22-85yrs) were enrolled for the study. The first 25 patients (group 1) received 80 cc contrast material, the second 25 patients (group 2) received 80 cc contrast material followed by 40 cc saline and the last 25 patients (group 3) received 60 cc contrast material followed by 40 cc saline. CT angiography was performed with a 16-slice MDCT scanner (Sensation 16, Siemens, Germany). Scan volume ranged from the ascending aorta to the intracranial circulation. Scan parameters: number of detectors/collimation 16/0.75 mm, feed/rotation 12 mm, rotation time 0.5 sec. CTA scan was started when bolus tracking measured an increase in density in the ascending aorta of 75 Hounsfield Units (HU). A region of interest inside the vessel lumen was measured in each scan throughout the data set, with a 1 second interval. Results: The mean HU in the ascending aorta in group 1, 2 and 3 was 281 ± 35 HU, 310 ± 43 HU and 270 ± 48 HU, respectively (group 1 vs 2 and 2 vs 3: p<0.01). The mean HU in the internal carotid artery in group 1, 2 and 3 was 380 ± 53 HU, 410 ± 86 HU and 293 ± 71 HU, respectively (group 2 vs 3: p<0.01). The mean HU in the intracranial vessels in group 1, 2 and 3 was 286 ± 67 HU, 286 ± 59 HU and 196 ± 47 HU, respectively (group 2 vs 3: p<0.01). The maximum enhancement in group 1, 2 and 3 was 385 ± 53 HU, 418 ± 79 HU and 317 ± 68 HU, respectively (group 2 vs 3: p<0.01). The mean enhancement in group 1, 2 and 3 was 321 ± 42 HU, 344 ± 58 HU and 263 ± 53 HU, respectively (group 2 vs 3: p<0.01). Conclusion: The use of a bolus chaser following 80 cc of contrast material provides a slightly higher opacification, but not significant in the internal carotid artery and intracranial vessels. Lowering the amount of contrast material from 80 cc to 60 cc results in a significantly lower opacification of the vessel lumen, especially in the proximal internal carotid artery and intracranial vessels. The optimal strategy is 80 cc contrast material followed by 40 cc saline.       Questions about this event email: c.demonye@erasmusmc.nl

De Monye MD, C, CT Angiography of the Carotid Artery with a 16-slice Multidetector CT Scanner: Comparison of Different Volumes of Contrast Material with and without Bolus Chaser.  Radiological Society of North America 2003 Scientific Assembly and Annual Meeting, November 30 - December 5, 2003 ,Chicago IL. http://archive.rsna.org/2003/3104291.html