3D打印技术制备大鼠脊髓仿生支架的研究

APPLICATION OF THREE DIMENSIONAL PRINTING ON MANUFACTURING BIONIC SCAFFOLDS OF SPINAL CORD IN RATS

目的探讨3D打印技术制备大鼠脊髓仿生支架方法,为用生物材料制备脊髓支架并进行脊髓损伤修复研究奠定基础。方法取3只雌性SD大鼠,采用7.0T动物专用核磁共振仪进行扫描,获得T8~10节段脊髓截面位置和形状图像,结合脊髓各神经传导束的位置和形状资料,应用Getdata数据获取软件获取相关数据。应用Solid Works三维制图软件进行支架三维模型设计,并将数据转换为立体平版印刷（stereolithography,STL）格式;最后以光敏树脂为材料,通过3D打印机制作脊髓仿生支架。结果 MRI扫描显示,T8~10节段脊髓截面呈纵轴较长、横轴相对较短的椭圆形,横径为（2.05±0.24）mm,纵径为（2.20±0.52）mm;其神经传导束在STL格式的三维模型中清晰显示,应用3D打印机制备了目标节段脊髓的仿生支架。该脊髓支架形态、截面与大鼠正常脊髓相似,其中各神经传导束孔隙位置模拟了大鼠脊髓正常神经传导束走行。结论 3D打印技术制备的大鼠脊髓支架与正常脊髓外形和尺寸接近,内部神经传导束通道也更仿生,且制作程序简便,有望用于脊髓损伤修复研究。

Objective To fabricate the bionic scaffolds of rat spinal cord by combining three dimensional （3D） printer and 3D software, so as to lay the foundation of theory and technology for the manufacture of scaffolds by using biomaterials. Methods Three female Sprague Dawley rats were scanned by 7.0T MRI to obtain the shape and position data of the cross section and gray matter of Ts to T,0 spinal cord. Combined with data of position and shape of nerve conduction beam, the relevant data were obtained via Getdata software. Then the 3D graphics were made and converted to stereolithography （STL） format by using SolidWorks software. Photosensitive resin was used as the materials of spinal cord scaffolds. The bionic scaffolds were fabricated by 3D printer. Results MR/showed that the section shape of Ts to T,0 segments of the spinal cord were approximately oval with a relatively long sagittal diameter of （2.20＋0.52） mm and short transverse diameter of （2.05＋0.24） ram, and the data of nerve conduction bundle were featured in the STL format. The spinal cord bionic scaffolds of the target segments made by 3D printer were similar to the spinal cord of rat in the morphology and size, and the position of pores simulated normal nerve conduction of rat spinal cord. Conclusion Spinal cord scaffolds produced by 3D printer which have similar shape and size of normal rat spinal cord are more bionic, and the procedure is simple. This technology combined with biomaterials is also promising in spinal cord repairing after spinal cord injury.