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Liver Segment VII – Right posterosuperior segment

The right posterosuperior segment (Segment VII) is part of the right hepatic lobe in the Couinaud classification. It is located in the superior and posterior aspect of the right lobe, extending to the diaphragmatic surface. It lies posterior to Segment VIII (right anterosuperior), superior to Segment VI (right posteroinferior), and lateral to Segment I (caudate lobe).

Segment VII is bounded medially by the right hepatic vein, which separates it from Segment VIII, and inferiorly by the portal vein bifurcation. Posteriorly, it is closely related to the diaphragm. Its anatomic position makes it less accessible surgically, and it is a frequent site for subdiaphragmatic abscesses, metastases, and hydatid cysts.

Synonyms

  • Segment VII of liver

  • Right posterosuperior segment

  • Superior posterior segment of right lobe

Function

  • Performs normal hepatic metabolic, detoxification, and synthetic functions

  • Processes nutrients from portal inflow and contributes to bile production

  • Plays a role in hepatic reserve during disease, though less accessible for surgery

Nerve Supply

  • Hepatic plexus (parasympathetic vagus fibers + sympathetic fibers from celiac plexus)

Arterial Supply

  • Branches from the posterior division of the right hepatic artery

Venous Drainage

  • Portal inflow: posterior branch of right portal vein

  • Hepatic venous outflow: drained mainly by the right hepatic vein, sometimes with accessory small veins into the IVC

MRI Appearance and Signal

T1-weighted images:

  • Normal parenchyma appears intermediate signal intensity

  • Diaphragmatic fat and IVC provide useful margins

T2-weighted images:

  • Parenchyma shows intermediate to mildly hyperintense signal

  • Cysts, hemangiomas, and edema appear markedly hyperintense

STIR:

  • Fat suppression improves lesion detection

  • Inflammation, edema, or infiltrative lesions appear hyperintense compared to background parenchyma

T1 Fat-Saturated (Pre-contrast):

  • Parenchyma: intermediate signal intensity, stands out against suppressed fat

  • Portal and hepatic veins remain dark flow voids

T1 Fat-Saturated Post-Contrast (Dynamic Gadolinium):

  • Arterial phase: homogeneous enhancement of normal parenchyma; hypervascular lesions (HCC, NET mets) appear bright

  • Portal venous phase: parenchyma enhances uniformly; hypovascular lesions (mets, cholangiocarcinoma) appear darker

  • Delayed phase: uniform attenuation in normal parenchyma; fibrosis or cholangiocarcinoma may show persistent enhancement

MRI Non-Contrast 3D Imaging:

  • Provides 3D mapping of segment VII’s location relative to diaphragm, IVC, and hepatic veins

  • Useful for pre-surgical planning, resection, and transplant mapping

Triple-Phase MRI (Dynamic Contrast):

  • Arterial phase: hypervascular lesions stand out against enhancing parenchyma

  • Portal venous phase: hypovascular lesions are most conspicuous

  • Delayed phase: assesses fibrosis, cholangiocarcinoma, or scarring with persistent enhancement

CT Appearance

CT Pre-Contrast:

  • Segment VII appears isoattenuating with rest of liver

  • Bordered by diaphragm and right hepatic vein

CT Post-Contrast (Single Phase):

  • Enhances homogeneously with other liver tissue

  • Lesions show variable enhancement depending on vascularity

Triple-Phase CT (Liver Protocol):

  • Arterial phase: parenchyma enhances; hypervascular lesions (HCC, hemangiomas early filling) appear bright

  • Portal venous phase: normal parenchyma is homogenously enhanced; hypovascular lesions appear hypoattenuating

  • Delayed phase: normal parenchyma washes out uniformly; fibrotic lesions and cholangiocarcinoma remain enhanced

CT Image

Liver Segment VII – Right posterosuperior segment CT axial anatomy image

CT Image

Liver right posterosuperior segment — Segment VII CT axial anatomy image

MRI image

Liver right posterosuperior segment — Segment VII MRI axial anatomy