Healthy controls have the same hepatic transit time (HTT) using SonoVue® and Luminity® but using Levovist® the HTT is significantly longer

Objective: Liver metastases lead to a shortening of the HTT of an echo enhancer. Former studies using Optison® showed a HTT of about 16s in healthy controls. Optison is currently unavailable and recent observations indicated that SonoVue® has a shorter HTT than Optison®. Hence we compared the HTT of present available contrast agents in healthy controls.

Method: 15 healthy controls with no visible liver lesions were enrolled in this study. We measured the HTT of three echo enhancers (SonoVue®, Luminity® and Levovist®), using low MI and CPS of Acuson sequoia®. The hepatic artery and a branch of the hepatic vein were visualized simultaneously in an intercostal section. The difference of the arrival time of the echo enhancer in the hepatic vein and the hepatic artery supplied the real HTT.

Results: The mean HTT of SonoVue was 9.9s (SD±2.2s), the mean HTT of Luminity was also 9.9s (SD±2.1s) and the mean HTT of Levovist was 14,2s (SD±2,9s). There was no difference between the HTT of SonoVue® and Luminity®, but the HTT of Levovist® was significantly longer (p<0.05).

Conclusion: Levovist® has a longer transit time than second generation contrast agents. In healthy controls SonoVue® and Luminity® show the same HTT. Previous studies indicated that the former used Optison® has a longer transit time. Further studies need to be done to clarify whether SonoVue® and Luminity® are useful to discriminate between patients with or without liver metastases.