title: Evaluation of short-term response of high intensity focused ultrasound ablation for primary hepatic carcinoma: utility of contrast-enhanced MRI and diffusion-weighted imaging.
abstract: OBJECTIVE
  To explore the significance of contrast-enhanced MRI (CE-MRI) and diffusion-weighted imaging (DWI) in evaluating the short-term response of high intensity focused ultrasound (HIFU) ablation for primary hepatic carcinoma (PHC).
  
  
  METHODS
  Thirty-nine lesions in the livers of 27 patients were performed HIFU ablation. Conventional MRI sequences, CE-MRI and DWI were performed 1 week before HIFU and 1 week, 3 months after the therapy, respectively. The short-term responses of HIFU for all lesions were evaluated with MRI.
  
  
  RESULTS
  28 of the 39 lesions (28/39, 71.8%) showed complete necrosis with no enhancement 1 week and 3 months after HIFU. The apparent diffusion coefficient (ADC) values 1 week and 3 months after HIFU were significantly higher than those 1 week before treatment (p<0.05). The tumor recurrence was detected in 7 of the 39 lesions (7/39, 17.9%) which had no significant enhancement 1 week after HIFU. On the 3 months follow-up, focal nodules were found on the inner aspects of the treated areas. The ADC values had no significant difference between 1 week before and after treatment (p>0.05), however, they were significantly higher 3 months after HIFU (p<0.05). The tumor residuals were detected in 4 of the 39 lesions (4/39, 10.3%) showing enhancement 1 week after treatment and increased size 3 months after HIFU. The ADC values had no significant difference among 1 week before HIFU, 1 week and 3 months after treatment (p>0.05).
  
  
  CONCLUSIONS
  CE-MRI and DWI can be employed to evaluate the short-term response of HIFU ablation for PHC and to guide the patient management.
authors.affiliation: Department of Radiology, Second Affiliated Hospital, Chongqing Medical University, Yuzhong District, Chongqing 400010, China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Jiannong
authors.initials: J
authors.lastname: Zhao
authors.forename: Dajing
authors.initials: D
authors.lastname: Guo
authors.forename: Weijia
authors.initials: W
authors.lastname: Zhong
authors.forename: Lifen
authors.initials: L
authors.lastname: Ran
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001707:Biopsy, Needle; D006528:Carcinoma, Hepatocellular / Q000473:pathology / Q000628:therapy*; D003287:Contrast Media / Q000008:administration & dosage; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D057086:High-Intensity Focused Ultrasound Ablation; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D016896:Treatment Outcome
chemical_list: D003287:Contrast Media