Surgical Implications of Portal Vein Variations and Liver Segmentations: A Recent Update

Anatomy of the Liver (A05.8.01.001). Worldwide Review, 2019. New Findings, Concepts and Definitions Support a Division of the Liver into Seven Portal Segments

“…Segment IV (A05.8.01.042) receives a segmental branch (6 mm) that arises to the right of the terminal bulb of the umbilical part of the left portal branch; in addition, there are two or three subsegmental branches that emerge from the right of the aforementioned bulb or from the upper edge of the transverse part of the left portal branch. The branch for segment V (10 mm of diameter) arises from the left portal branch in 21 % of cases [Iqbal et al (2017), reported 20-35 % of these cases]; it emerges from the right portal branch in 79 %; the branch for segment V, after deepening 2 cm in its segmental parenchyma, gives anterior, lateral, posterior and medial branches which encompass the parenchyma between the right portal fissure (A05.8.01.036) and the main portal fissure (A05.8.01.035) from the inferior borderof the liver (A05.8.01.024) to the inferior vena cava (A12.3.09.001). The branch for segment V is the only one existing for the right medial division (A05.8.01.046) of the liver.…”

“…The portal vein and its branches attract the arterial and biliary duct to form seven portal pedicles for seven portal segments (Durand-López, 2016;Hikspoors et al 2017a,b). Iqbal et al (2017) reports the trifurcation of the portal vein when entering the liver. Arterial irrigation of the liver.…”

Right Hepatectomy In Patient with Absent Portal Vein Bifurcation

“…If not recognized, severe complications in form of postoperative remnant liver ischemia, portal vein thrombosis and death can be expected [1,3]. With careful preoperative imaging and planning, successful hepatectomy and liver transplantation can be carried out without difficulty [4,5].…”

Surgical Anatomy of the liver

“…The majority of the hepatic inflow (75-80%) comes through the portal vein with nutrient rich but oxygen depleted blood form the gastrointestinal tract (via coronary vein, SMV and IMV) and the spleen and pancreas (via splenic vein) [1] . to supply segmentsII, III and IV [8][9][10][11] . It then terminates in a connection to the ligamentum teres (obliterated foetal umbilical vein and may communicate to the IVC through the ligamentum venosus (obliterated foetal ductus venosus) [1] .…”

“…In up to 10-15 % of individuals the portal vein trifurcates into right anterior, right posterior and left portal vein at a common place. Also, the right posterior portal vein may arise from the main portal vein instead of the right portal vein in 0.3-7% of individuals [9] .…”