The watershed between right and left hepatic artery territories: findings on CT scans after transcatheter oily chemoembolization of hepatic tumors. A preliminary report

Abstract

The goals of this study were to delineate the boundary between the right and left hepatic artery territories by computed tomography (CT), to compare this boundary with the middle scissura of Couinaud’s segmental anatomy, and to discuss the clinical implications of these findings. The 18 patients who underwent transcatheter oily chemoembolization (TOCE) of liver tumors via the right or left hepatic artery, were examined with an immediate postembolization CT scan. We measured the orientation of the watershed line between the right and left hepatic artery territories and the orientation of the middle scissura on other available sectional imaging modalities, and then compared the middle scissura with the arterial watershed line. A part of segment IV was fed by the right hepatic artery in two of 18 (11.1%) patients. Moreover, one of 4 segment IV lesions was embolized via right hepatic artery infusion. Thus, in 11.1% of cases there was no coincidence between the arterial watershed line and the middle scissura. Some segment IV lesions may be fed and therefore embolized only via right hepatic artery infusion in TOCE for liver tumor.