title: Assessment of radiofrequency ablation margin by MRI-MRI image fusion in hepatocellular carcinoma.
abstract: OBJECTIVE
  To investigate the feasibility and clinical value of magnetic resonance imaging (MRI)-MRI image fusion in assessing the ablative margin (AM) for hepatocellular carcinoma (HCC).
  
  
  METHODS
  A newly developed ultrasound workstation for MRI-MRI image fusion was used to evaluate the AM of 62 tumors in 52 HCC patients after radiofrequency ablation (RFA). The lesions were divided into two groups: group A, in which the tumor was completely ablated and 5 mm AM was achieved (n = 32); and group B, in which the tumor was completely ablated but 5 mm AM was not achieved (n = 29). To detect local tumor progression (LTP), all patients were followed every two months by contrast-enhanced ultrasound, contrast-enhanced MRI or computed tomography (CT) in the first year after RFA. Then, the follow-up interval was prolonged to every three months after the first year.
  
  
  RESULTS
  Of the 62 tumors, MRI-MRI image fusion was successful in 61 (98.4%); the remaining case had significant deformation of the liver and massive ascites after RFA. The time required for creating image fusion and AM evaluation was 15.5 ± 5.5 min (range: 8-22 min) and 9.6 ± 3.2 min (range: 6-14 min), respectively. The follow-up period ranged from 1-23 mo (14.2 ± 5.4 mo). In group A, no LTP was detected in 32 lesions, whereas in group B, LTP was detected in 4 of 29 tumors, which occurred at 2, 7, 9, and 15 mo after RFA. The frequency of LTP in group B (13.8%; 4/29) was significantly higher than that in group A (0/32, P = 0.046). All of the LTPs occurred in the area in which the 5 mm AM was not achieved.
  
  
  CONCLUSIONS
  The MRI-MRI image fusion using an ultrasound workstation is feasible and useful for evaluating the AM after RFA for HCC.
authors.affiliation: Xiao-Li Wang, Kai Li, Zhong-Zhen Su, Ze-Ping Huang, Ping Wang, Rong-Qin Zheng, Department of Ultrasound, the Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, Guangdong Province, China.
authors.forename: Xiao-Li
authors.initials: XL
authors.lastname: Wang
authors.affiliation: Xiao-Li Wang, Kai Li, Zhong-Zhen Su, Ze-Ping Huang, Ping Wang, Rong-Qin Zheng, Department of Ultrasound, the Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, Guangdong Province, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Li
authors.affiliation: Xiao-Li Wang, Kai Li, Zhong-Zhen Su, Ze-Ping Huang, Ping Wang, Rong-Qin Zheng, Department of Ultrasound, the Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, Guangdong Province, China.
authors.forename: Zhong-Zhen
authors.initials: ZZ
authors.lastname: Su
authors.affiliation: Xiao-Li Wang, Kai Li, Zhong-Zhen Su, Ze-Ping Huang, Ping Wang, Rong-Qin Zheng, Department of Ultrasound, the Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, Guangdong Province, China.
authors.forename: Ze-Ping
authors.initials: ZP
authors.lastname: Huang
authors.affiliation: Xiao-Li Wang, Kai Li, Zhong-Zhen Su, Ze-Ping Huang, Ping Wang, Rong-Qin Zheng, Department of Ultrasound, the Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, Guangdong Province, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Wang
authors.affiliation: Xiao-Li Wang, Kai Li, Zhong-Zhen Su, Ze-Ping Huang, Ping Wang, Rong-Qin Zheng, Department of Ultrasound, the Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, Guangdong Province, China.
authors.forename: Rong-Qin
authors.initials: RQ
authors.lastname: Zheng
mesh_terms: D000328:Adult; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000473:pathology* / Q000601:surgery*; D017115:Catheter Ablation / Q000009:adverse effects; D003287:Contrast Media / Q000008:administration & dosage; D004867:Equipment Design; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000295:instrumentation / Q000379:methods*; D008113:Liver Neoplasms / Q000473:pathology* / Q000601:surgery*; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods*; D008297:Male; D008875:Middle Aged; D018365:Neoplasm, Residual; D011237:Predictive Value of Tests; D011446:Prospective Studies; D016896:Treatment Outcome
chemical_list: D003287:Contrast Media
keywords: Ablative margin; Hepatocellular carcinoma; Image fusion; Magnetic resonance image; Radiofrequency ablation