RESUMO
BACKGROUND: This study aimed to examine the inflow and outflow vascular system of the caudate lobe and determine its relevance to hepatobiliary surgery. METHODS: A total of 41 cadaveric liver specimens were dissected in 2019 to evaluate the inflow and outflow vascular system of the caudate lobe. RESULTS: The Glisson's pedicles of the paracaval portion were mainly from the right pedicle in 14 cases (34.15%), mainly from the left pedicle in 22 cases (53.66%), and equally from the left and right pedicle in 5 cases (12.19%). Many thick branches of the portal vein were found behind the plane consisting of the hilar plate and Arantius ligament, but none of them were thicker than 1 mm in front of the plane. All of the veins of the caudate lobe drained into the inferior vena cava (IVC) via the anterior face. There was an avascular zone without short hepatic veins (SHVs) consisting of loose connective tissue between the retrohepatic IVC and caudate lobe, with its length and width being 45-97 mm and 6-15 mm, respectively. CONCLUSIONS: The plane consisting of the hilar plate and Arantius ligament can be regarded as the boundary between the caudate lobe and the other lobes. There is an avascular zone without SHVs consisting of loose connective tissue between the retrohepatic IVC and caudate lobe.