title: CT Angiography Covering Both Cervical and Cerebral Arteries on a 16-Detector Row System: Modification of Contrast Dose and Injection Rate by Patient Weight.
abstract: We assessed the feasibility of modifying the contrast dose and injection rate based on patient weight in four patient groups in whom CT angiography was performed with contrast agent 350 mgI/mL at different injection doses in combination with a saline flush (40 mL). Patients were assigned to one of four groups: group A: injection dose (ID) of 1.3 mgI/kg; group B: ID of 1.1 mgI/kg; group C: ID of 0.9 mgI/kg; and group D (the control group): a fixed dose of 75 mL at 3 mL/s (25 s). In groups A to C, the injection time was fixed at 20 s. We measured the attenuation of target vessels and visually assessed the images obtained. The average dose and rates were 81.3/4.1, 63.8/3.2, and 49.4/2.5 (mL/mL/s) for groups A, B, and C, respectively. The doses of groups B and C were significantly smaller that that of group D. Cerebral vessels showed no significant attenuation difference between group D and groups A and B, but the attenuation of only a few assessed regions was significantly lower in group C than in group D. In the visual assessment, no difference was found among the four groups. Cervical and cerebral CT angiograms can be obtained at a dose of 1.1 mgI/kg, which can effectively reduce the contrast dose.
authors.affiliation: Department of Radiology, Kyorin University Faculty of Medicine; Shinkawa, Mitaka; Tokyo, Japan - maimai.rad@gmail.com.
authors.forename: M
authors.initials: M
authors.lastname: Imai
authors.forename: K
authors.initials: K
authors.lastname: Tsuchiya
authors.forename: M
authors.initials: M
authors.lastname: Yoshida
authors.forename: T
authors.initials: T
authors.lastname: Nitatori