Blood supply to the caudate lobe of the liver from the right inferior phrenic artery: observation by cone-beam computed tomography during arteriography

Purpose To retrospectively evaluate blood supply to the caudate lobe of the liver from the right inferior phrenic artery (RIPA) using cone-beam computed tomography during arteriography (CBCTA-RIPA). Methods CBCTA-RIPA examinations during transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) were collected from 2448 procedures in 787 patients. The exclusion criteria were (1) major artifacts, (2) TACE of hepatic arterial branches before performing CBCTA-RIPA, and (3) repeated CBCTA-RIPA studies in the same patient. Blood supply to three subsegments, the Spiegel lobe (SP), paracaval, and caudate process, was evaluated on CBCTA-RIPA images. The origins and routes of branches supplying the caudate lobe were also evaluated by three-dimensional vessel-tracking software. Results Forty-seven CBCTA-RIPA examinations in 47 patients (38 with a history of TACE [repeated TACE group] and nine without it [initial TACE group]) were eligible, including five who had previously undergone hepatectomy. Seven had caudate lobe HCCs. Blood supply to the caudate lobe was demonstrated in 21 (44.7%) patients: in 50% (19/38) and 22.2% (2/9) of the repeated and initial TACE groups, respectively. The caudate arteries had previously been embolized in eight patients, the RIPA branch in three, and both in one. Forty-one proximal branches mainly supplied the dorsal part of the SP. All branches but five reached there through the inferior vena cava (IVC) ligament. The RIPA supplied eight of nine caudate lobe HCCs, totally ( n = 7) or partially ( n = 1). Conclusion The proximal RIPA branches mainly supply the dorsal SP through the IVC ligament, especially in the repeated TACE group.