A 55-year-old male with a 10-year history of chronic hepatitis B presents with 4 months of dull right upper quadrant pain, fatigue, decreased appetite, and weight loss. Physical exam shows no jaundice, mild tenderness on percussion over the liver area, no hepatosplenomegaly. Ultrasound reveals a 2cm×3cm×4cm round hypodense lesion in the right liver lobe. Alpha-fetoprotein is negative. Which of the following is the preferred method to differentiate this from hepatic hemangioma?