Abstract

Background: Anatomical variations in the formation of the portal vein are frequently encountered during cadaveric dissections and can have profound clinical implications in hepatic surgeries and interventions. Despite being welldocumented in literature, these variants often remain underrecognized in routine surgical practice and medical training. Aim and Objective: To document and analyze a rare anatomical variation in the formation of the portal vein observed during routine cadaveric dissection and raise clinical awareness about variations in portal venous confluence that may affect surgical approaches and outcomes. Material and Methods: A routine dissection was performed on an 84-year-old female cadaver in the Department of Anatomy, AIIMS-Gorakhpur. Observations regarding the formation of the portal vein were documented both diagrammatically and through photographic evidence. Standard anatomical references and literature were consulted to classify and compare the observed variation. Result: The portal vein was found to be formed by the convergence of the superior mesenteric vein (SMV), splenic vein (SV), and notably, the inferior mesenteric vein (IMV) contributing directly at the confluence—an uncommon variant aligning with Type II of Thomson’s classification. Conclusion: This case highlights a clinically relevant variation in portal vein formation with potential implications for hepatic surgeries, liver transplantations, and interventional radiology. Early recognition through imaging or dissection is critical for effective surgical planning and minimizing complications.

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Funding