title: Effect of a poloxamer 407-based thermosensitive gel on minimization of thermal injury to diaphragm during microwave ablation of the liver.
abstract: OBJECTIVE
  To assess the insulating effect of a poloxamer 407 (P407)-based gel during microwave ablation of liver adjacent to the diaphragm.
  
  
  METHODS
  We prepared serial dilutions of P407, and 22.5% (w/w) concentration was identified as suitable for ablation procedures. Subsequently, microwave ablations were performed on the livers of 24 rabbits (gel, saline, control groups,n= 8 in each). The P407 solution and 0.9% normal saline were injected into the potential space between the diaphragm and liver in experimental groups. No barriers were applied to the controls. After microwave ablations, the frequency, size and degree of thermal injury were compared histologically among the three groups. Subsequently, another 8 rabbits were injected with the P407 solution and microwave ablation was performed. The levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN) and creatinine (Cr) in serum were tested at 1 d before microwave ablation and 3 and 7 d after operation.
  
  
  RESULTS
  In vivoablation thermal injury to the adjacent diaphragm was evaluated in the control, saline and 22.5% P407 gel groups (P= 0.001-0.040). However, there was no significant difference in the volume of ablation zone among the three groups (P> 0.05). Moreover, there were no statistical differences among the preoperative and postoperative gel groups according to the levels of ALT, AST, BUN and Cr in serum (allP> 0.05).
  
  
  CONCLUSIONS
  Twenty-two point five percent P407 gel could be a more effective choice during microwave ablation of hepatic tumors adjacent to the diaphragm. Further studies for clinical translation are warranted.
authors.affiliation: Li-Li Zhang, Yu-Jiang Liu, Rui Dou, Lin-Xue Qian, Department of Ultrasound, Beijing Friendship Hospital, Capital Medical University, Beijing 100054, China.
authors.forename: Li-Li
authors.initials: LL
authors.lastname: Zhang
authors.affiliation: Li-Li Zhang, Yu-Jiang Liu, Rui Dou, Lin-Xue Qian, Department of Ultrasound, Beijing Friendship Hospital, Capital Medical University, Beijing 100054, China.
authors.forename: Gui-Min
authors.initials: GM
authors.lastname: Xia
authors.affiliation: Li-Li Zhang, Yu-Jiang Liu, Rui Dou, Lin-Xue Qian, Department of Ultrasound, Beijing Friendship Hospital, Capital Medical University, Beijing 100054, China.
authors.forename: Yu-Jiang
authors.initials: YJ
authors.lastname: Liu
authors.affiliation: Li-Li Zhang, Yu-Jiang Liu, Rui Dou, Lin-Xue Qian, Department of Ultrasound, Beijing Friendship Hospital, Capital Medical University, Beijing 100054, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Dou
authors.affiliation: Li-Li Zhang, Yu-Jiang Liu, Rui Dou, Lin-Xue Qian, Department of Ultrasound, Beijing Friendship Hospital, Capital Medical University, Beijing 100054, China.
authors.forename: John
authors.initials: J
authors.lastname: Eisenbrey
authors.affiliation: Li-Li Zhang, Yu-Jiang Liu, Rui Dou, Lin-Xue Qian, Department of Ultrasound, Beijing Friendship Hospital, Capital Medical University, Beijing 100054, China.
authors.forename: Ji-Bin
authors.initials: JB
authors.lastname: Liu
authors.affiliation: Li-Li Zhang, Yu-Jiang Liu, Rui Dou, Lin-Xue Qian, Department of Ultrasound, Beijing Friendship Hospital, Capital Medical University, Beijing 100054, China.
authors.forename: Xiao-Wei
authors.initials: XW
authors.lastname: Wang
authors.affiliation: Li-Li Zhang, Yu-Jiang Liu, Rui Dou, Lin-Xue Qian, Department of Ultrasound, Beijing Friendship Hospital, Capital Medical University, Beijing 100054, China.
authors.forename: Lin-Xue
authors.initials: LX
authors.lastname: Qian
mesh_terms: D000410:Alanine Transaminase / Q000097:blood; D000818:Animals; D001219:Aspartate Aminotransferases / Q000097:blood; D001806:Blood Urea Nitrogen; D006528:Carcinoma, Hepatocellular / Q000628:therapy*; D017115:Catheter Ablation / Q000379:methods*; D003404:Creatinine / Q000097:blood; D003964:Diaphragm / Q000293:injuries*; D005260:Female; D005782:Gels; D006358:Hot Temperature; D006801:Humans; D008099:Liver / Q000528:radiation effects; D008113:Liver Neoplasms / Q000628:therapy*; D008297:Male; D008872:Microwaves; D020442:Poloxamer / Q000737:chemistry*; D011817:Rabbits; D011832:Radiation Injuries / Q000517:prevention & control*; D012212:Rheology; D013696:Temperature
chemical_list: D005782:Gels; D020442:Poloxamer; D003404:Creatinine; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase
keywords: Hepatocellular carcinoma; Hydrodissection; Injury; Microwave ablation; Poloxamer