Imaging of the liver: a survey update of prevailing techniques for conventional CT scanning.
Silverman PM., Cooper C., Zeman RK.
A survey of the Society of Computed Body Tomography/Magnetic Resonance (SCBT/MR) was performed to assess current techniques in liver CT scanning.The study was designed as an update to a study performed in 1987. The survey was distributed to 67 members of the SCBT/MR at 35 institutions.Twenty-six institutions responded. As in 1987, none relied solely on noncontrast scans. In 1987, only 54% (12/22) of institutions performed contrast-enhanced scans as their primary technique compared with 73% (19/26) in 1993. Ionic contrast was used exclusively in the earlier study, whereas in the present study 58% used nonionic contrast in the majority of cases and 38% used nonionic contrast routinely. In 1987, 41% performed scans with a power injector compared with 85% in the present study. Enhanced scans were performed during the contrast bolus in 36% of institutions in 1987 compared with 76% in this study. No institution relied on noncontrast scans alone. In the previous study the delay between injection and scanning was variable (0-60 s), whereas in the present study 83% specified a delay of 21-45 s.Significant refinements in CT technique, wider use of power injectors, utilization of nonionic contrast, and a more critical approach to optimize liver imaging have created a significant impact on the practice of liver CT.