An anatomical imposter in the left upper quadrant: Incidental beaver tail liver on chest computed tomography

Beaver tail liver, also known as a sliver of liver, is a rare anatomic variant in which the left hepatic lobe extends laterally to the splenic region. Although usually asymptomatic, its imaging appearance may simulate perisplenic pathology and result in diagnostic confusion. A 55-year-old man presented to the infectious disease clinic with cough and dyspnea. Because of persistent respiratory symptoms and a history of tobacco use, non-contrast chest computed tomography was performed to evaluate possible pulmonary parenchymal abnormalities. On the lower sections of the scan, a structure with attenuation similar to that of the liver parenchyma was noted in the left upper abdominal quadrant adjacent to the spleen. Multiplanar reconstructed coronal and sagittal images demonstrated direct continuity of this structure with the left hepatic lobe, extending as a narrow tongue-like projection toward the spleen. These findings were consistent with beaver tail liver. No evidence of splenic injury, hematoma, perisplenic fluid collection, or focal mass was identified. The patient was managed conservatively for the respiratory symptoms, and no additional diagnostic or therapeutic intervention was required for this benign hepatic variant. Beaver tail liver is a rare but clinically important anatomic variant that may mimic perisplenic disease on imaging studies. Recognition of its continuity with the left hepatic lobe on multiplanar imaging and its similar attenuation to normal liver parenchyma is essential for accurate diagnosis and avoidance of unnecessary intervention.