title: [Value of computed tomography and magnetic resonance imaging in diagnosis and differential diagnosis of small hepatocellular carcinoma].
abstract: OBJECTIVE
  To analyze the computed tomography (CT) and magnetic resonance imaging (MRI) findings of small hepatocellular carcinoma to improve the accuracy in the diagnosis.
  
  
  METHODS
  This retrospective analysis involved 41 patients with small hepatocellular carcinoma cases confirmed by pathological examination of the biopsy samples or follow-up. These patients were assessed for CT and MRI findings including lesion size, density or signal intensity, enhancement patterns, and presence of tumor capsules.
  
  
  RESULTS
  On unenhanced CT images, small hepatocellular carcinomas were displayed mainly as low-density masses, and the majority of tumors presented with low signal intensity on T1-weighted unenhanced MR images with increased signal intensity on T2-weighted images in comparison with the surrounding liver parenchyma. Most of tumors showed intense enhancement during the arterial phase (CT in 15 cases and MRI in 13 cases), but some appeared isointense to the liver parenchyma (CT in 4 cases and MRI in 4 cases). In portal and delayed phases, the tumors typically had lower signal intensity than that of the surrounding liver tissues (CT in 25 cases and MRI in 12 cases) with enhancement of the tumor capsules (13 cases).
  
  
  CONCLUSIONS
  Dynamic enhanced scanning can be more informative of the pathology and blood supply of small hepatocellular carcinoma. Early and late arterial phase imaging may help in detecting the small lesions and in making differential diagnosis.
authors.affiliation: Diagnostic Imaging Center, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Ma
authors.forename: Xue-lin
authors.initials: XL
authors.lastname: Zhang
authors.forename: Xin-yu
authors.initials: XY
authors.lastname: Li
authors.forename: Lin
authors.initials: L
authors.lastname: Zhang
authors.forename: Huan-huan
authors.initials: HH
authors.lastname: Su
authors.forename: Chuan-yin
authors.initials: CY
authors.lastname: Zhan
mesh_terms: D000328:Adult; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis* / Q000000981:diagnostic imaging; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007089:Image Enhancement; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed