hUMass Medical School, Worcester, Massachusetts. iUniversity of Florida College of Medicine, Gainesville, Florida. jRush University Medical Center, Chicago, Illinois; American College of Surgeons. kNew York University Medical Center, New York, New York. lStanford University Medical Center, Stanford, California. mUniversity of Alabama Medical Center, Birmingham, Alabama. nUniversity of Alabama Medical Center, Birmingham, Alabama. oJohns Hopkins Bayview Medical Center, Baltimore, Maryland. pUniversity of Illinois College of Medicine, Chicago, Illinois; American College of Physicians. qJohns Hopkins Hospital, Baltimore, Maryland. rSpecialty Chair, Virginia Commonwealth University Medical Center, Richmond, Virginia. Reprint requests to: publications@acr.org Liver Lesion-Initial Characterization For MRI, extracellular gadolinium-based contrast agents are commonly used in a variety of clinical settings. However, hepatobiliary contrast agents were developed to assist with detection and characterization of liver lesions. Two such agents are available: gadoxetate disodium and gadobenate dimeglumine. Hepatobiliary agents have the advantage of hepatobiliary phase (HBP) in addition to the dynamic postcontrast phases. In the HBP, parenchymal uptake of the contrast agent provides avid enhancement of the liver and therefore the ability to detect nonhepatocellular lesions. Of the two agents, gadoxetate is used more widely for HBP imaging as its HBP occurs approximately 20 minutes after injection as compared with 1 to 2 hours when using gadobenate. A positron-emitting radioisotope-labeled somatostatin analogue called Ga-68-DOTATATE utilized in PET/CT is designed to image neuroendocrine tumors (NETs). It offers a higher spatial resolution and considerably shorter imaging times compared with In-111 somatostatin receptor or metaiodobenzylguanidine scintigraphy [8]. Discussion of Procedures by Variant Variant 1: Indeterminate, greater than 1 cm liver lesion on initial imaging with US.
Liver Lesion Initial Characterization. hUMass Medical School, Worcester, Massachusetts. iUniversity of Florida College of Medicine, Gainesville, Florida. jRush University Medical Center, Chicago, Illinois; American College of Surgeons. kNew York University Medical Center, New York, New York. lStanford University Medical Center, Stanford, California. mUniversity of Alabama Medical Center, Birmingham, Alabama. nUniversity of Alabama Medical Center, Birmingham, Alabama. oJohns Hopkins Bayview Medical Center, Baltimore, Maryland. pUniversity of Illinois College of Medicine, Chicago, Illinois; American College of Physicians. qJohns Hopkins Hospital, Baltimore, Maryland. rSpecialty Chair, Virginia Commonwealth University Medical Center, Richmond, Virginia. Reprint requests to: publications@acr.org Liver Lesion-Initial Characterization For MRI, extracellular gadolinium-based contrast agents are commonly used in a variety of clinical settings. However, hepatobiliary contrast agents were developed to assist with detection and characterization of liver lesions. Two such agents are available: gadoxetate disodium and gadobenate dimeglumine. Hepatobiliary agents have the advantage of hepatobiliary phase (HBP) in addition to the dynamic postcontrast phases. In the HBP, parenchymal uptake of the contrast agent provides avid enhancement of the liver and therefore the ability to detect nonhepatocellular lesions. Of the two agents, gadoxetate is used more widely for HBP imaging as its HBP occurs approximately 20 minutes after injection as compared with 1 to 2 hours when using gadobenate. A positron-emitting radioisotope-labeled somatostatin analogue called Ga-68-DOTATATE utilized in PET/CT is designed to image neuroendocrine tumors (NETs). It offers a higher spatial resolution and considerably shorter imaging times compared with In-111 somatostatin receptor or metaiodobenzylguanidine scintigraphy [8]. Discussion of Procedures by Variant Variant 1: Indeterminate, greater than 1 cm liver lesion on initial imaging with US.