In utero torsion of an accessory hepatic lobe mimicking a congenital tumor.

Accessory hepatic lobes are rare anatomic variants connected to the liver by a fibrous stalk or parenchymal attachments. They are usually detected incidentally, but torsion is a rare complication. Here, we report torsion of an accessory hepatic lobe occurring in utero with a focus on the MRI findings. The lesion mimicked a congenital tumor, and we provide potential clues that may have narrowed the differential diagnosis prior to surgical exploration.