IMAGING OF THE LIVER - A SURVEY UPDATE OF PREVAILING TECHNIQUES FOR CONVENTIONAL CT SCANNING

Background: A survey of the Society of Computed Body Tomography/Magnet ic Resonance (SCBT/MR) was performed to assess current techniques in l iver CT scanning. Methods: The study was designed as an update to a st udy performed in 1987. The survey was distributed to 67 members of the SCBT/MR at 35 institutions. Results: Twenty-six institutions responde d. 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 w as used exclusively in the earlier study, whereas in the present study 58% used nonionic contrast in the majority of cases and 38% used -non ionic contrast routinely. In 1987, 41% performed scans with a power in jector compared with 85% in the present study. Enhanced scans were per formed during the contrast bolus in 36% of institutions in 1987 compar ed 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 de lay of 21-45 s. Conclusion: 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 signif icant impact on the practice of liver CT.