title: Plane and weighted tri-phase helical CT findings in the diagnosis of liver focal nodular hyperplasia.
abstract: OBJECTIVE
  To analyze the pre- and post-contrast CT findings of liver focal nodular hyperplasia (FNH) so as to improve their diagnostic accuracy.
  
  
  METHODS
  Pre- and post-contrast tri-phase (arterial, portal venous and delayed) scans were performed in 21 patients with FNH proved surgically and pathologically. Transcatheter arterial angiography was performed in 2 patients.
  
  
  RESULTS
  Pre-contrast scans showed hypodensity in 16 patients, isodensity in 5, and punctate, streak and radial scars in 12. Except central scar, all lesions were markedly and homogeneously enhanced in the arterial phase. Nine of the 21 patients showed dilated and tortuous arteries in the central and peripheral areas of the focus. In the portal venous phase, focal density was decreased, though still higher or slightly higher in FNH than in parenchyma. In the delayed phase, the lesions showed isodensity or slight hypodensity. Enhanced capsules were seen in 3 patients. Dilated arteries and drainage veins were seen on angiographic images.
  
  
  CONCLUSIONS
  The characteristic manifestations of FNH on multiphasic helical CT scan are of great significance in diagnosing FNH and choosing viable therapy.
authors: Department of Radiology, Eastern Hepatobiliary Surgery Hospital, Shanghai 200438, China.
authors: Ai-Min
authors: AM
authors: Xu
authors: Hong-Yan
authors: HY
authors: Cheng
authors: Dong
authors: D
authors: Chen
authors: Yu-Chen
authors: YC
authors: Jia
authors: Meng-Chao
authors: MC
authors: Wu
mesh_terms: D000293:Adolescent; D000328:Adult; D000792:Angiography; D005260:Female; D020518:Focal Nodular Hyperplasia / Q000000981:diagnostic imaging* / Q000473:pathology; D006499:Hepatic Artery / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011169:Portal Vein / Q000000981:diagnostic imaging / Q000503:physiopathology; D036542:Tomography, Spiral Computed; D014664:Vasodilation