Reduction of contrast material volume in 3D angiography of the brain using MDCT.

OBJECTIVE

Our aim was to investigate the image quality of MDCT angiography of the brain at a low-volume of contrast material.

SUBJECTS AND METHODS

One hundred patients were randomly assigned to one of two groups, which differed with regard to contrast material volume and subsequent saline bolus: group A was administered 300 mg I/mL, 50 mL at an injection rate of 3.0 mL/s followed by a 20-mL saline bolus at 3.0 mL/s; group B was administered 300 mg I/mL, 100 mL at 3.0 mL/s. Of 100 total patients, 82 were analyzed: 45 in group A and 37 in group B. The attenuation and visualization of intracranial arteries were compared between the two groups. The regions of interest (ROIs) were drawn throughout the data set: internal carotid artery (ROI 1), anterior cerebral artery (ROI 2), middle cerebral artery (ROI 3), vertebral artery (ROI 4), basilar artery (ROI 5), and posterior cerebral artery (ROI 6). The differences were assessed with a Student's t test. Two readers evaluated images and graded vascular delineation of intracranial arteries by consensus.

RESULTS

Eighty-two patients were investigated strictly according to the study protocol and were included in the per-protocol population. There were no statistically significant differences between the two groups in average attenuation (p = 0.21) and visual analysis (p = 0.84).

CONCLUSION

When performing 3D angiography of the brain using 16-MDCT, the use of a 20-mL saline flush allows reduction of contrast material from 100 mL to 50 mL if all other factors are unchanged.