The Experimental Study About The Effect Of Blood Supply To Cryoablation In VX2 Liver Tumor Model

ObjectiveMake use of the effect of medcine to the blood supply of tumor,observe the effect of blood supply to cryoablation in a VX2 liver tumor model..Methods50 New Zealand white rabbits were implanted into left liver with VX2 tumor,45 were successful which were randomly divided into three groups,the group A were given with As₂O₃,the group B were given with epinephrine,the group C were control group,cryoablation on tumor after laparoscopy,CT perfusion were performed before and after cryoablation,calculate blood flow(BF),blood volume(BV)and permeability surface of area product(PS)of tumors,observe the diameters of cryoablation in CT scan and analyze their difference.After the cryoablation,sacrifice the rabbits and got the livers,separated the cryoablation area into two parts,one part was stained with Triphyl tetrazolium chloride(TTC),calculate the diameter in this vital stain;the other part was stained with nicotinamide adenine dinucleotide diaphorase (NADH-diaphorase),observe the change in pathology.Results1.The mean largest diameter of cryoablation calculated by CT scane in group A,B and C were 2.3±0.3 cm,0.9±0.2 cm,1.6±0.2 cm(the value of F is 126. 824,P＜0.001),th e difference between every group was significantly,P＜0.001.2.The lesions of cryoablation were out of TTC vital stain,other area were red,t he mean largest diameter out of TTC stain from group A to C were 2.1±0.2c m,0.8±0.2cm,1.5±0.2cm(the value of F is 132.738,P＜0.001),compare withth e extent calculated by CT scane,the difference between the twomethods was s ignificant,P＜0.001.3.(1)Before the cryoablation,the values of BF from group A to group C in th e tumors were 26.57±6.45(ml/100g·min)/91.67±8.88(ml/100g·min)/63.75±8.29 (ml/100 g·min)(the value of F is 253.646,P＜0.001),the difference between every group was significant,P＜0.001;the values of BV were 8.42±3.56(ml/10 0g)/21.23±3.27(ml/100g)/14.68±3.42(ml/100g)separately(the value of F is 5 2.653,P＜0.001),the difference between every group was significant,P＜0.001;t he values of PS were 17.86±3.25ml/100g·min)/23.86±2.96(ml/100g·min)/20.36±3.50(ml/100g·min)separately(the value of F is 12.938,P＜0.001),the differenc e between every group was significant,P＜0.001.(2)After cryoablation therapy, thevalues of BF in VX2 tumors from group A to group C were 12.11±6.45 (ml/100g·min)/14.09±2.79(ml/100g·min)/12.35±2.98(ml/100g·min)(the value of F is 2.689,P＞0.05);the values of BV were 3.31±1.25(ml/100g)/3.38±1.21 (ml/100g)/3.57±1.32(ml/100g)(the value of F is 0.168,P＞0.05);the values of PS were25.09±3.01(ml/100g·min)/26.84±1.92(ml/100g·min)/26.36±3.3 2(ml/10 0g·min)(the value of F is 0.763,P＞0.05).(3)After cryoablation,the value of B F,BV were decreased compared with before it in every group,P＜0.05,the val ue of PSwere all increased,P＜0.05,the differences were significant.4.Utilize the Pearson correlation analysis,the coefficient correlation between BV and t he diameter out of stain in TTC was 0.787,P＜0.05.5.There were necrosis area,degeneration area,nomal area in NADH-diaphorase s tain.Conclusions1.AS₂O₃ can reduce the tumor blood supply obviously when epinephrine increase it,when blood supply in tumor increase,the extent of cryoablation diminution.2.The stain of TTC can reflect the change of enzyme in the cryoablation are t he extent were smaller compare with the cryoablation extent calculated by CT scane,the difference is significantly.After cryoablation,the value of BV and BF in tumors were decrease than before it,the values of PS were increase.3.After cryoablation,the difference about the values of BV,BF and PS betwee n groups were not signanficant.4.CT perfusion imaging is capable of quantitative assessment to the change of blood parameter before and after cryoablation.5.NADH-diaphorase vital stain can reflect the cell activital in cryoablation area.