摘要
目的探讨不同方法监测组织工程骨血管化的优缺点,寻找较好的监测方法。方法在13只成年恒河猴的25侧胫骨上制备2cm的骨膜与骨缺损模型,根据骨缺损充填材料不同随机分为五组(每组5侧),A组：β-磷酸三钙(β-TCP)+骨髓基质下细胞(BMSCs)+血管束；B组：β-TCP+血管束；C组：β-TCP+ BMSCs；D组：β-TCP；E组：空白对照。术后4、8、12周行磁共振灌注成像检查并计算信号强度-时间(SI-T)曲线的最大线性斜率(SS_(max))和基线值(SI_(baseline)),拍摄恒河猴胫骨X线片并计算其透光度,行放射性核素骨显像检查并计算摄取比值,同时进行组织学检查。结果术后4、8、12周A组的SS_(max)值最高,术后8周与4周相比SS_(max)有较大幅度的提高(P=0．003)。术后12周A组5个样本的SS_(max)与X线片透光度呈负相关(rs=～0．892,P=0．042),与血管面积比值呈正相关(rs=0．894,P=0．041)。结论SI-T曲线的SS_(max)能够准确地反映组织工程骨的血管化情况,磁共振灌注成像检查具有无创、无辐射、高灵敏度和定量分析的优点。
Objective To compare four methods of monitoring vascularization of tissue engineered bone in the rhesus so as to find our the best. Methods Twenty-five lower limbs of 13 rhesuses were used in this study to make models of tibial diaphyseal defect of 20 mm which were to be fixed with an AO reconstruction plate of 7 holes. The monkeys were randomly divided into five groups according to defect filling materials： group A： β-tricalcium phosphate （β-TCP） and bone marrow stromal cells （BMSCs） and blood vessel bundles; group B： β-TCP and blood vessel bundles; group C： β-TCP and BMSCs; group D： β-TCP; group E： blank. Perfusion weighted MR imaging （PWMR）, X-ray, radionuclide imaging and histological examinations were carried out at weeks 4, 8, 12 postoperatively. The maximum slope rates of the single intensity-time curve （SSmax） and values of baseline （SIbaseline） were calculated at the same time points. Transmittances of the X-ray films were assessed. Ratios between isotope counts in region of interest （ROI） were calculated. Chinese ink perfusion and calculation of blood vessel areas were done for histological examinations. Results Compared with other groups, the SS,,ox in group A was the highest at weeks 4, 8, 12 postoperatively. In group A, the SSmax at week eight was significantly higher than that at week four （ P = 0. 003）, and the SSmax and transmittance of X-ray were negatively related at week 12 after operation （ rs = -0. 892, P = 0. 042）, but the SSmax and blood vessel area were positively related （ rs = 0. 894, P = 0.041 ） Conclusions PWMR can be a sensitive, quantitative, noninvasive and non-radiant method to monitor vascularization of tissue engineered bone, because SSmax of the single intensity-time curve of PWMR can reflect the most accurately the process of vascularization of tissue engineered bone.
出处
《中华创伤骨科杂志》
CAS
CSCD
2006年第6期544-548,共5页
Chinese Journal of Orthopaedic Trauma
基金
国家高技术发展计划(863计划)重大专项(2003AA205010)
关键词
组织工程骨
血管化
监测
磁共振灌注成像
Tissue engineered bone
Vascularization
Monitoring
Perfusion weighted MR imaging
