| There are three parts in our study. Material properties of the domestic perfusion agent(DPA), using DPA in cadaveric specimens and clinical studies were investigated to evaluate the feasibility and safety of using DPA on percutaneous vertebroplasty(PVP).Part 1:An experimental study on material properties of domestic perfusion agent used on percutaneous vertebroplasty.Objective To evaluate the material properties of DPA with different mixing ratio and seek an appropriate mixing ratio of DPA whose material properties was similar to the imported perfusion agent(IPA).Method DPA was classified into twelve groups according to the ratio of powder/liquid (g/ml) as 2 : 1, 3 : 2, 4 : 3, and the percentage of BaS04 in powder as 0,10%, 20%, 30%, while the ratio of powder/liquid (g/ml) of IPA accord to manufacturer's recommendation (2 : 1).The total, groups amount to 13. peak temperature and time of temperature above 50 and 60 during the period of polymerization, polymerization time, CT value, strength and stiffness were measured respectively in each group, which included 8 samples. Two factors, the ratio of powder/liquid and the percentage of BaS04 in powder, which affect the material properties of DPA, were analyzed by univariate multi-factorial ANOVA. One-way ANOVA was analysed on the material properties of DPA and IPA, A Dunnett' s post hoc comparison text was conducted to determine whether the differences were significant, using the group of IPA as control group. Result The polymerization time, the peak temperature during the period of polymerization, the CT value, the strength and the stiffness of DPA with different ratio of powder/liquid and the percentage of BaS04 in powder were significantly different(P<0. 05) , moreover, two factors have interaction on the polmerization time, the peak temperature during the period of polymerization, and the strength of DPA. But the time of temperature above 50 and 60 during the period of polymerization were not significantly different (P >0. 05) . The DPA whose ratio of powder/liquid (g/ml)was 3 : 2 and the percentage of BaS04 in powder was 20% has the similar mechanical properties compared with the IPA, furthermore it' s radiopacity and viscousness are superior to the IPA.Conclusion DPA could have tailored material properties by altering its mixing ratio. The DPA whose ratio of powder/iquid (g/ml)was 3 : 2 and the percentage of BaS04 in powder was 20% has the analogous material properties with the IPA. It is hopeful to use DPA on the PVP.Part 2 An experimental study of domestic perfusion agent for use with vertebroplasty in a cadaveric spinal compression fracture model. Objective To determine whether the- biomechanical properties of vertebral bodies (VBs) subjected to compression fractures and subsequently treated with DPA or IPA were different. We also want to evaluate the radiopacity and dispersion ability of DPA and IPA used in VBs, furthermore the probability of leakage by using DPA or IPA on vertebroplasty attracts us too. Method Five VBs from each of four spines harvested from female cadavers (age, 75 5 years) were disarticulated and compressed in a materials testing machine to determine initial strength and stiffness. The fractures were repaired by using DPA whose ratio of powder/iquid (g/ml)was 3 : 2 and the percentage of BaS04 in powder was 20%, or IPA whose mixing ratio followed manufacturer' s recommendation on vertebroplasty. After augmentation, the VBs were screened by CT, then recrushed. Repeated measures ANOVA was used to check for an effect of treatment on stiffness and strength of VBs. Radiopacity and dispersion ability of DPA and IPA used in VBs were analyzed by two independent-samples T text and Wilcoxon measures respectively, x2 text was conducted to determine whether the differences of probability of leakage by using DPA or IPA on vertebroplasty were significant. Result Augmentation with DPA result in a similar biomechanical properties compared with IPA. There are significant differences in radiopacity and dispersion ability between DPA...
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