Right gastric vein

The right gastric vein, also known as pyloric vein, forms part of the venous drainage network of the stomach and proximal duodenum. It is a tributary of the portal vein.

Gross anatomy

Location

The right gastric vein courses parallel to the right gastric artery adjacent to the lesser curvature of the stomach ⁶.

Origin

The right gastric vein originates from the confluence of more diminutive venous tributaries emanating from the lesser curvature of the stomach. It travels in tandem with its namesake artery, coursing rightward through folds of lesser omentum, draining the prepyloric vein as it courses over the pylorus ⁵.

Termination

It commonly drains into the main (or left) portal vein behind the first part of the duodenum.

Variant anatomy

The right gastric vein demonstrates significant anatomical variation, reported to occur in 1.5-49% of patients, more commonly than variant anatomy of the left gastric vein. Variations in structure, origin, and termination (often referred to as aberrant right gastric venous anatomy) have been described in the following patterns ⁴: 

• terminating in a peripheral portal venous branch
  • may appear as a single, well-delineated channel
  • alternatively, may anastomose via collateralisation
    • meeting the recipient vessel in an end-to-side or end-to-end manner
• direct drainage into the liver parenchyma
  • as manifest angiographically by a superficial blush in the hepatic parenchyma ⁴
  • patterns with single ¹⁰ and multiple sites of drainage have been observed
• ramification into a perivascular network prior to drainage into a segmental or sectional portal venous branch

Clinical importance

• surgical anatomical considerations
  • vessel identification and ligation may be required prior to adjacent lymph node dissection ⁸
• metastasis
  • may be a route of hepatic metastases in gastric neoplasms
• recognition of associated hepatic parenchymal anomalies ⁹
  • focal fatty sparing in the posterior aspect of segment 4 ²
    • in the context of diffuse hepatic steatosis
  • hepatic segmental atrophy, most commonly involving segment 2 ⁷