title: Contrast-enhanced ultrasound features of histologically proven small (≤20 mm) liver metastases.
abstract: OBJECTIVE
  We analyzed contrast-enhanced ultrasound (CEUS) features of histologically proved small (≤20 mm) liver metastases, in comparison to small (≤20 mm) hepatocellular carcinomas (HCC), to define the differentiate diagnoses value of CEUS in clinical practice.
  
  
  METHODS
  Eighty-two cases of small (≤20 mm) liver metastases and 84 cases of small (≤20 mm) HCC were retrospectively reviewed. All patients had CEUS images. Two radiologists assessed CEUS enhancement pattern and time of enhancement in consensus. Statistical analyses were performed using SPSS v.19.0 (SPSS Inc., Chicago, IL). The χ2test and the independent sample t-test were used to compare the differences.
  
  
  RESULTS
  Comparing to small HCCs, rapid rim-like hyper-enhancement in arterial phase (56.1% in liver metastases vs. 2.3% in HCCs, p < .01), rapid wash-out and become hypo-enhancement in late arterial phase or early portal venous phase (96.4% in liver metastases vs. 22.6% in HCCs, p < .01) with central non-enhanced area in late phase were characteristic CEUS features of small metastases.
  
  
  CONCLUSIONS
  CEUS imaging enhancement findings reliably offer typical signs of small liver metastases, differentiate effectively with small HCCs. CEUS can help to improve the diagnostic confidence of small liver metastases.
authors: a Department of Ultrasound , Zhongshan Hospital, Fudan University , Shanghai , China.
authors: Yi
authors: Y
authors: Dong
authors: b Department of Ultrasound , Shanghai Institute of Imaging , Shanghai , China.
authors: Xiao-Long
authors: XL
authors: Zhang
authors: b Department of Ultrasound , Shanghai Institute of Imaging , Shanghai , China.
authors: Feng
authors: F
authors: Mao
authors: a Department of Ultrasound , Zhongshan Hospital, Fudan University , Shanghai , China.
authors: Bei-Jian
authors: BJ
authors: Huang
authors: c Department of Ultrasound , 81st Hospital of Chinese PLA , Nanjing Jiangsu , China.
authors: Qin
authors: Q
authors: Si
authors: a Department of Ultrasound , Zhongshan Hospital, Fudan University , Shanghai , China.
authors: Wen-Ping
authors: WP
authors: Wang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging* / Q000473:pathology; D002681:China; D003287:Contrast Media; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008099:Liver / Q000473:pathology; D008103:Liver Cirrhosis / Q000150:complications*; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis / Q000000981:diagnostic imaging*; D012189:Retrospective Studies; D014463:Ultrasonography / Q000379:methods*
chemical_list: D003287:Contrast Media
keywords: Contrast-enhanced ultrasound; liver; metastasis; small