Experimental Study On Ultrasonically Guided Percutaneous Microwave Coagulation Therapy For VX2 Carcinoma Transplanted Into Rabbit Breast

Purpose:1.To establish animal model of VX2 carcinoma transplanted into rabbit breast and explore the tissue morphology and hemodynamics of tumors by high-frequency ultrasound.2.To explore the effectiveness of water cooled microwave antenna percutaneous sonographically guided microwave coagulation therapy for VX2 carcinoma transplanted into rabbit breast.Material and methods:Trenty-eight white New Zealand rabbit models were randomly divided into two groups one week after VX2 carcinoma transplanted into breasts:PMCTtreatment group(13,16 tumors),control group(15). control group were assessed by high-frequency color Doppler ultrasound every week for six weeks.And hemodynamic parameters of tumor arteries such as PSV,PI and RI were measured using Doppler ultrasound with spectral analysis and compared with themselves.coagulation guided under US with microwave at 25～45 watts for 1～3 minutes was performed to the animals in treatment group at 2nd～3rd week after tumor implantation.As to greater tumors,two or more coagulations were needed.Two thermoscopes were used to observe the temperature change during PMCT and therapy was ceased when centigrade reached 60℃.Three animals with two tumors were killed and speciments were cut and studied grossly and microscopically at the 0,1st,4th week after PMCT.Ten animals of control group were abserved at the same time with ten animals of treatment group until most of them were dead.The survival time,survival rates of all animals,the growth and metastasis of tumors were observed after PMCT.Results:1.In two-dimensional images ,tumors were small and poor echo one week after implantation and the tumor growth rate was 463.09% and calcified lesions were seen at the 2nd～3rd week. Necrosis or liquefaction appeared and swollen lymphonodi axillares could be found later and at the 5th～6th week cavum formed.Color Doppler flowing imaging (CDFI) showed dot,branch,or line flow signals and the degree of blood abundance was from 0 to III grades;arterial spectrum was investigated and PSV changed from 6.03 to 39.8cm/s and RI changed from 0.168 to 0.622.At the 2nd～3rd week ,...