磁共振灌注成像监测组织工程骨血管化的实验研究  

Perfusion-weighted magnetic resonance imaging for monitoring vascularization in tissue-engineered bone in rhesuses

作　　者：王学明[1] 裴国献[1] 金丹[1] 魏宽海[1] 江汕[1] 唐光辉[1] 

机构地区：[1]南方医科大学南方医院创伤骨科,广东广州510515

出　　处：《南方医科大学学报》2006年第7期931-935,共5页Journal of Southern Medical University

基　　金：国家高技术发展计划(863计划)重大专项(2003AA205001)

摘　　要：目的探讨磁共振灌注成像在组织工程骨血管化监测中的应用价值。方法在13只恒河猴的25个胫骨上制备20mm的骨膜与骨缺损,依据填充的材料不同随机分为五组,A组:β-磷酸三钙(β-TCP)+骨髓基质干细胞(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(SSmax)和基线值(SIbaseline),拍摄恒河猴胫骨X线片并计算其透光度,同时行放射性核素骨显像检查。结果术后4、8、12周A组的SSmax值最高,术后8周与4周相比SSmax有较大幅度的提高(P=0.003)。术后8周A组5个样本的同位素计数比值与磁共振灌注成像检查的SSmax呈正相关关系(rs=0.899,P=0.038),术后12周A组5个样本的SSmax与X线片透光度呈负相关(rs=-0.892,P=0.042)。结论SI-T曲线的SSmax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、高灵敏度和可定量分析的优点。Objective To assess the value of perfusion-weighted magnetic resonance （MR） imaging （PWMRI） in monitoring vascularization in tissue-engineered bone graft. Methods Tibial diaphyseal defect of 20 mm was induced in 25 lower limbs of 13 rhesuses and fixed with an AO reconstruction plate with 7 holes. The monkeys were randomized into 5 groups according to the materials used for defect filling： group A, with β-tricalcium phosphate （β-TCP）, bone marrow stromal cells （BMSCs） and blood vessel bundles; group B, with β-TCP and blood vessel bundles; group C, with β-TCP and BMSCs; group D, with β-TCP, and group E without filling. PWMRI, X-ray, and radionuclide imaging were carried out at weeks 4, 8, 12 postoperatively, The maximum slope rates of the single intensity-time curve （SSmax） and the baseline values （SIbeseline） on the same time points were calculated. Transmittances on the X-ray films and isotope counts in the region of interest （ROI） were assessed and calculated. Results Compared with other groups, group A showed the highest SSmax at weeks 4, 8, and 12 postoperatively, and its SSmax, at week 8 was significantly higher than that at week 4 （P=0.003）. The SSmax, was positively related to isotope counts in ROI at week 8 after operation （rs=0.899, P=0.038）, and inversely related to transmittance on X-ray films at week 12 （rs=-0.892, P=0.042）. Conclusion The SSmax of the single intensity-time curve can accurately reflect the vascularization of the tissue-engineered bone graft, and PWMRI allows sensitive, quantitative, noninvasive and radiation-free vascularization monitoring.

关 键 词：磁共振灌注成像 组织工程骨 血管化 

分 类 号：R318.1[医药卫生—生物医学工程]