Objective: The aim of this prospective study was to investigate the effect of different volumes of contrast material on vascular enhancement in 16-channel multi-detector row computed tomographic angiography of the brain.
Methods: A total of 194 patients were divided into 3 groups who received different volumes of contrast material: 100 (n = 62), 80 (n = 72), and 60 mL (n = 60). The attenuation values were measured on transverse images at 12 different intracranial vessels (right and left internal carotid arteries, A2s, M2s, and P2s, basilar artery, vein of Galen, superior sagittal sinus, and dominant sigmoid sinus). The image quality parameters (intra-arterial contrast, arterial delineation, venous contamination, and confidence in diagnosis) were graded by 2 observers in consensus using a 5-point scale.
Results: The attenuation values at the left A2 segment, superior sagittal sinus, and sigmoid sinus were significantly lower in the 60-mL group than those in other groups, whereas no significant differences were found between the 3 groups for the remaining intracranial vessels. For qualitative evaluation, arterial delineation was rated higher in the 100- and 80-mL groups, whereas less venous contamination was found in the 60-mL group. There was no significant difference in overall image quality (the sum of the scores for 4 image quality parameters) between the 3 groups.
Conclusions: A contrast material volume of 60 mL (18 g iodine) provides excellent image quality of cerebral multi-detector row computed tomographic angiography comparable to those achievable with 100 and 80 mL.