Focal Hepatic Fatty Infiltration in the Posterior Edge of the Medial Segment Associated with Aberrant Gastric Venous Drainage: CT, US, and MR Findings

OBJECTIVE: The purpose of this study is to demonstrate the relation between focal hepatic fatty infiltration and aberrant gastric venous drainage (AGVD) in the posterior edge of the medial segment (PEMS) of the liver. MATERIALS AND METHODS: We present two cases of focal hepatic fatty infiltration with AGVD in the PEMS and discuss their imaging features. RESULTS: In both cases the focal fatty infiltration areas were hyperechoic on sonography, hypodense on CT, and hyperintense on T1-weighted MRI. Computed tomography during arterial portography (CTAP) showed nodular perfusion defects corresponding to the areas in both cases, and early enhancement of the area was observed with dynamic MRI in one case. Although the findings on CTAP and dynamic MRI suggested a neoplastic nature for the lesions, focal fatty infiltration was confirmed with surgical resection in one case and with imaging follow-up in the other. Aberrant gastric venous drainage into the area was demonstrated on arteriography in both cases. CONCLUSION: The variation in blood supply caused by AGVD may play an important role in fatty metabolism in the PEMS of the liver and may influence imaging features.