Hepatomegaly

Michael P. Federle, MD, FACR

Brooke R. Jeffrey, MD

Key Facts

Terminology

Enlargement of liver due to underlying pathologic process

Imaging

Best diagnostic clue: Hepatic length > 15 cm
- Normal liver length 8-12 cm for men, 6-10 cm for women in midclavicular line
Liver protrudes beyond costal margin
Best imaging tool: Longitudinal US or coronal triphasic CT

Top Differential Diagnoses

Riedel lobe
Caudate hypertrophy in Budd-Chiari or PSC
Liver displacement by COPD
Lobar regeneration with major liver resection

Clinical Issues

Most common signs/symptoms
- Palpable liver edge below costal margin
Other signs/symptoms
- Jaundice, RUQ pain, fever, abnormal liver function tests
Benign outcome to fulminant liver failure
Often biopsy required for definitive diagnosis

Diagnostic Checklist

Hepatitis, steatosis, passive congestion, and diffuse tumor are most common causes
Image interpretation pearls
- Consider triphasic CT to detect and characterize mass lesions

(Left) Coronal CECT reformation of a 52-year-old man with metastatic colon cancer shows marked enlargement of the liver with diffuse metastases throughout the right lobe

. (Right) Venous phase coronal CECT of a 27-year-old woman with leukemia and new onset of RUQ pain shows an enlarged and heterogeneous liver with distended hepatic veins

and IVC

due to passive congestion of the liver. Drug toxicity accounted for the cardiac dysfunction.

(Left) Longitudinal ultrasound in a 44-year-old man with a history of hepatitis B infection shows marked enlargement of the right lobe of the liver, extending caudally below the level of the kidney

. (Right) Longitudinal ultrasound in a 38-year-old woman with nonalcoholic steatohepatitis reveals marked hepatic enlargement. Note the right lobe extending below the level of the right kidney

as well as echogenicity greater than that of the kidney due to diffuse steatosis.