Dynamic Study On The Effect Of Different Embolic Particles On Renal Blood Perfusion In Rabbits

Objective:To investigate the embolic effect on renal blood flow with two commercially available embolic particles of different sizes and shapes and assess the blood perfusion recovery in embolism region by using computed tomography perfusion imaging technique.Material and Method:A total of 24 healthy rabbits were randomly divided into four groups:A,B,C and D.There were six rabbits in each group.Right renal CT perfusion imaging was performed on all experimental rabbits.BF and BV values of renal cortex were recorded.Then the lower poles of the right kidneys were superselectively embolized with different embolic particles.The experimental subjects in group A and B were embolized with polyvinyl alcohol(PVA)in size of 150-350μ.m and 560-710μm.The experimental subjects in group C and D were embolized with Embosphere in size of 100-300μm and 500-700μm.All the experimental rabbits in the four groups were underwent right renal CT perfusion imaging examination either the day,3 days,7 days or 30 days after the embolization procedure.And the BF and BV values of the embolism region were recorded every time.The BF and BV values in each group were compared in pairs among different time points by using repeated-measures analysis of variance.The BF and BV values at each time point were compared in pairs among different groups by using LSD(Least Significant difference)test.P<0.05 was considered statistically significant.Results:All superselectively embolization procedures were performed successfully and the BF and BV values were recorded at different time points in each group as expected.According to the holistic analysis,the BF and BV values among different groups had no significant difference(F=0.674,P=0.578;F=3.088,P=0.050).It indicated that the effect of different embolic particles on renal blood perfusion was similar.The BF and BV values among different time points had significant statistic difference(F=1.619E3,P<0.05;F=3.712E3,P<0.05).The interaction between time and group was also statistically significant(F=9.357,P<0.05;F=7.488,P<0.05).The results certified that the blood perfusion in the embolism region showed a trend of change over time.In addition,due to the difference of embolic particles,the changes of the blood perfusion were also different with time.The BF and BV values in each group were compared in pairs among different time points.There were statistical differences among different time points in each group.The BF and BV values at each time point were compared in pairs among different groups.It showed that the BF and BV values among different groups at each time point had no significant difference before the embolization procedure.The groups in which the embolic particles had the same shape and different sizes were compared.The blood perfusion in the large particle groups was significantly higher than that in the small particle groups at the follow-up time of the day,3 days,7 days and 30 days after the embolization procedure(Group B>Group A,Group D>Group C,P<0.05).The groups in which the embolic particles had the similar size and different shapes were compared.The blood perfusion in the irregular particle groups was significantly higher than that in the spherical particle groups at the follow-up time of the day and 30 days after the embolization procedure(Group A>Group C,Group B>Group D,P<0.05).The blood perfusion in the irregular particle groups was similar with that in the spherical particle groups 3 days after the embolization procedure.The blood perfusion in the spherical particle groups was significantly higher than that in the irregular particle groups 7 days after the embolization procedure(Group C>Group A,Group D>Group B,P<0.05).Conclusion:For the same shape particles,the embolic effect on renal blood flow with smaller particles was better than that with larger particles.For the similar size particles,the embolic effect on renal blood flow with spherical particles was better than that with irregular particles.The blood perfusion recovery in embolism region was related to the shape of embolic particles.In the early days after embolization procedure,the blood perfusion recovery in embolism region with spherical particles was more quickly than that with irregular particles.However,the blood perfusion recovery in embolism region with spherical particles was more slowly than that with irregular particles at middle-late stage after embolization procedure.