Ablation of Hepatic Tumors Simultaneous 微波消融治疗肝肿瘤的同时课件.ppt

Comparison of Microwave and Radiofrequency Ablation of Hepatic Tissue in a Porcine in vivo Model. Andrew Wright MD, Chris Johnson, Fred Lee Jr. MD, and David Mahvi MD Microwave Ablation Theoretical advantages over radiofrequency ablation No ground pad Not limited by tissue charring and impedence changes Larger zone of active heating Use of Multiple Probes Hypothesis Because microwave and radiofrequency ablation are both heat based, there will be no difference in ablation size or lesion pathology between the two technologies Methods Microwave Ablation Vivant Medical prototype system 10 minute ablation, 40 Watts Radiofrequency Ablation RITA Medical Systems Starburst 10 minute ablation, 3cm deployment 100oC target temperature Microwave Ablation System Radiofrequency Ablation System Treatment Protocol Nineteen crossbred female swine 0, 2, and 28 day survival groups Mix of MW and RF lesions in each animal Pathology, serial CT scanning 28 Day survival group 4 MW or 4 RF lesions in each animal Pathology, serial lab draws Lesion Volume Lesion Length Lesion Diameter Laboratory Data No significant difference in AST, ALT, LDH, Alkaline Phosphatase, WBC, or HCT Pathology CT Imaging Summary MW lesions longer than RF Pathological and radiologic characteristics similar between RF and MW ablation Both MW and RF cause thrombocytopenia at 48 hours MW ablation technically easier than multiple-prong RF ablation Conclusions MW creates similar zones of coagulation necrosis as RF MW ablation has several theoretical advantages over RF Larger zone of active heating Ability to use multiple probes * * Departments of Radiology and Surgery University of Wisconsin Hospital ? Vivant Medical ? 13g, 15cm dipole antenna ? 915MHz generator ? Fiberoptic temperature monitor ? RITA Medical ? 14g, 15cm expandable array ? 460 kHz generator ? Integrated thermocouple * * * p=.02 * * ? ? ? * p.001 ? p=.02 ? p.001 ? * * p0.001 RFA MW Immediate 48o 4 weeks 48 Hours 4 Weeks *