用放射性核素监测组织工程骨修复效果的实验研究

目的　探讨组织工程骨对兔骨缺损的修复能力及放射性核素技术对其的监测作用。方法　 2 4只新西兰大白兔在双侧桡骨制成 15mm骨缺损。左侧植入磷酸钙人工骨 (CPC)和骨髓基质干细胞 (BMSCs)复合体 ,右侧植入CPC。采用核素骨显像和γ计数定量分析于术后 4、8、12周监测骨修复情况。结果　复合骨移植较人工骨有明显的放射性聚集 ,核素骨显像的感兴趣区计数、γ计数定量分析差异有极显著性 (P <0 0 1)。结论　组织工程骨较人工骨具有更佳的修复动物骨缺损的能力 ,放射性核素技术对修复过程有比较准确的监测效果。

Using radionuclide imaging for monitoring repairment of bone defect with tissue-engineered bone graft in rabbits

Objective To observe the effect of tissue-engineered bone grafts in repairing bone defect in rabbits,and assess the value of radionuclide for monitoring the therapeutic effect of this approach. Methods Bilateral radial defects of 15 mm in length in 24 rabbits were made. The tissue-engineered bone grafts (composite graft) contained bone marrow stromal cells(BMSCs) of rabbits and calcium phosphate cement (CPC) were grafted in left side defects,CPC only grafts (artificial bone graft) in right defects. After the operation,radionuclide was used to monitor the therapeutic effects at 4,8 and 12 weeks. Results 99 Tc m-methylene diphosphonic acid (MDP) radionuclide bone imaging indicated that there was more radionuclide accumulation in grafting region of composite than that of CPC. There was significant difference between 99 Tc m-MDP uptake of the region of interest (ROI) and scintillant counts of composite bone and the artificial bone (P<0.01). Conclusion Tissue-engineered bone grafts is eligible for repairing radial bone defects,and radionuclide imaging may accurately monitor the revascularization and bone regeneration after the bone graft implantation.