Middle hepatic vein

Fig. 20.1. Hepatic segmental anatomy. RHP right hepatic vein MHP middle hepatic vein LHV left hepatic vein RPV right portal vein LPV left portal vein...

Fig. 20.2a,b. Assessment of hepatic volumetry in a living liver donor. Hepatic volumes are determined by manuallytracing the contours of both the entire liver and the graft (segments 5-8) in the venous phase, a The volume of the donor s liver is calculated together with (b) the volume of the remnant liver, deemed sufficient, after left hepatectomy. The virtual hepatectomy plane followed the middle hepatic vein, corresponding to the plane of the performed surgery... 

When the infrarenal IVC is occluded, the hepatic segment of the IVC is invariably patent. This area is most conveniently accessed via one of the hepatic veins with subsequent catheterization of the IVC and right atrium. The middle hepatic vein is ideal and can be targeted with ultrasound. After access, the tunnel or pocket are typically fashioned on the chest wall for easy use (Azizkhan 1992). 

Fig. 1.2. In this spectral Doppler tracing the sensitive gate has been placed over the middle hepatic vein (arrowhead) and the trace shows the normal pattern where the predominant flow towards the heart (shown below the line to indicate flow away from the transducer) is interrupted by reverse flow as blood is returned to the liver in cardiac systole...

Fig. 4.2. Inferior aspect of the liver the round ligament continues into the umhilical portion of the left portal vein (at an anatomical landmark called Rex s recessus). The hepatic pedicle spreads out, near the liver, as a virtual space called the porta hepatis or hepatic hilum (defined by the bifurcation of the portal vein) and divides into a shorter right pedicle and a longer left pedicle. The left pedicle separates a quadrate lobe anteriorly and a round caudate lobe posteriorly and arches up as an umbilical portion to join the round ligament. Arantius ligament runs from the angle between the transverse portion and the umbilical portion of the left portal vein to the confluence of the left and middle hepatic veins. The right hepatic pedicle is in contact with the gallbladder that defines the right border of the quadrate lobe. Posteriorly the right hepatic pedicle is separated from the vena cava by a rim of liver tissue that corresponds to the right portion of the caudate lobe...

The simplified scheme assumes that the blood enters the liver from the portal vein (the arteries and the bile ducts follow the branches of the portal vein, so only the portal anatomy will be described henceforth) and is collected by three hepatic veins (left, middle and right) inserting into the inferior vena cava (Fig. 4.3). The main portal vein divides into two branches, right and left, defining a right liver and a left liver. The middle hepatic vein drains the liver from the main bifurcation. 

Middle hepatic vein Left hepatic vein... 

The separation between the right and the left liver is evident when the right branch and the left branch of the portal vein are injected with dyes of different colours (Fig. 4.4). The plane of separation between the right and the left liver can be approximated as a plane going from the gallbladder fossa to the vena cava in which runs the middle hepatic vein. 

The right and the left liver the plane separating the right and the left liver runs from the middle hepatic vein, to the inferior vena cava, to the gallbladder. 

In the left liver the main landmark is the left portal vein, and the second landmark is the left hepatic vein. The left portal vein describes a smooth arch from the main bifurcation to the lunbihcal ligament. All liver tissue comprised by the concavity of the arch and the middle hepatic vein will be segment 4. On the convex-... 

Fig. 4.16. Liver cast of an organ showing different abnormalities. The portal vein trifurcates rather than bifurcates. The right hepatic vein (RHV) is hypoplastic and the middle hepatic vein (MHV) is hypertrophic. Despite the variations, the different abnormalities can be reconciled with the usual segmental pattern, with segments of different sizes...

Fig. 5.1a-d. Sequential CT scan through the liver with Couinaud s segments divided and numbered. RHV, right hepatic vein MHV, middle hepatic vein LHV, left hepatic vein IVC, inferior vena cava RPV, right portal vein LPV, left portal vein FL, falciform ligament... 

Fig. 24.4. a CT image of a colorectal metastasis adjacent to the middle hepatic vein, b Under CT guidance, a needle is inserted into the metastasis to enable a coil to be sited within the tumour, c The coil is now demonstrated within the tumour, d Under fluoroscopic guidance a triple, cooled electrode (Radionics) is introduced into the tumour, using the coil as the target. An occlusion balloon is inflated in the adjacent hepatic artery to reduce cooling from blood flow, e A subsequent CT shows an area of coagulation produced by the RF ablation... 

Couinaud s surgical anatomy is based on the liver s portal and hepatic venous systems. The liver is divided by oblique-vertical planes defined by the three hepatic veins and a transverse plane through the right and left main portal branches. The middle hepatic vein... 

The surgical line for right-lobe harvesting in living-donor liver transplantation runs 1 cm right of the middle hepatic vein and parallel to Cantlie s line, and corresponds to a relatively avascular plane (Deshpande et al. 2002 Erbay et al. 2003). For left lateral segment transplantation, the transection is performed along the main lobar fissure. 

Fig. 4.2.1a,b. 3D volume rendering (VR) of a liver with virtually divided and colored segments along vascular landmarks, a Inferior and b antero-posterior views. The middle hepatic vein divides left and right liver, while the portal vein divides superior and inferior regions... 

Variations of the hepatic venous anatomy are observed in up to 30% of potential donors. The site of the confluence of the middle hepatic vein should be... 

Fig. 4.2.34a,b. Axial (a) and coronal (b) MIP images of the CT angiogram show the vein from segment Vlll (arrows) draining into the middle hepatic vein... 

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