ABSTRACT
Objective To investigate whether the percutaneous ethanol injection (PEI)under sedation and analgesia can in-crease the energy deposition and curative efficiency of the high intensity focused ultrsound(HIFU)in treating unresectable middle and advanced stages of primary liver cancer.Methods Thirty-six cases of clinically diagnosed unresectable middle and advanced sta-ges of primary liver cancer were randomly divided into the PEI+ HIFU group(combination group,n = 23)and the simple HIFU group (HIFU group,n=13);10mL of the mixture of 99.7% ethanol and iodized oil (9:1)was given by intratumoral injection at 30 min before ablation in the PEI+HIFU group,while 0.9% physiological saline 10mL was replaced in the simple HIFU group.The ablation energy efficiency factor(EEF)and irradiation time were compared between the two groups.Results The ablation EEF in the PEI+HIFU group and the simple HIFU group were (13.82+4.26)J/mm3 and (25.63+6.31)J/mm3 respectively,the PEI+HIFU group was significantly lower than the simple HIFU group (P <0.05);the irradiation time were (1 468.28+253.21)s and (2 352.56+463.34)s respectively;which in the PEI+ HIFU group was significantly shortened (P <0.05).Conclusion PEI can enhance the HIFU ablation energy deposition and improve the efficiency of HIFU for treating unresectable primary liver cancer.