title: Small hypervascular hepatocellular carcinoma versus hypervascular pseudolesions: differential diagnosis on MRI.
abstract: BACKGROUND
  We wanted to differentiate small hypervascular hepatocellular carcinoma (HCC) from hypervascular pseudolesion (HPL) on magnetic resonance imaging (MRI).
  
  
  METHODS
  We reviewed small hypervascular foci (< or = 2 cm in diameter) on dynamic MRI in patients with chronic liver disease, which were followed-up with serial MRI examinations.
  
  
  RESULTS
  Twenty of 34 hypervascular foci were larger at follow-up; 19 of 20 foci had characteristics suggesting HCC; and 14 foci did not grow or disappeared and were judged to be HPLs. There were no differences in the initial sizes and follow-up periods between HCCs and HPLs. On initial MRI, nine of 19 HCCs (47%) and one of 14 HPLs (7%) appeared hyperintense on T2-weighted images. The difference between HCCs and HPLs on T2-weighted images was statistically significant (p = 0.039).
  
  
  CONCLUSIONS
  HPLs are seen frequently as small hypervascular foci on dynamic MRI in patients with chronic liver disease. Hyperintensity of the foci on T2-weighted images differentiates HCCs from HPLs.
authors.affiliation: Department of Radiology, Niigata University Faculty of Medicine, 1-757, Asahimachi-Dori, Niigata, 951-8510, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kamura
authors.forename: M
authors.initials: M
authors.lastname: Kimura
authors.forename: K
authors.initials: K
authors.lastname: Sakai
authors.forename: T
authors.initials: T
authors.lastname: Ichida
authors.forename: H
authors.initials: H
authors.lastname: Seki
authors.forename: S
authors.initials: S
authors.lastname: Yamamoto
authors.forename: T
authors.initials: T
authors.lastname: Ozaki
mesh_terms: D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000473:pathology*; D003937:Diagnosis, Differential; D005500:Follow-Up Studies; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D012189:Retrospective Studies