Division of Biomedical Engineering, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
Tissue Eng Part C Methods. 2011 Nov;17(11):1071-80. doi: 10.1089/ten.tec.2011.0102. Epub 2011 Aug 26.
Scaffold visualization is challenging yet essential to the success of various tissue engineering applications. The aim of this study was to explore the potential of X-ray diffraction enhanced imaging (DEI) as a novel method for the visualization of low density engineered scaffolds in soft tissue. Imaging of the scaffolds made from poly(L-lactide) (PLLA) and chitosan was conducted using synchrotron radiation-based radiography, in-line phase-contrast imaging (in-line PCI), and DEI techniques as well as laboratory-based radiography. Scaffolds were visualized in air, water, and rat muscle tissue. Compared with the images from X-ray radiography and in-line PCI techniques, DEI images more clearly show the structure of the low density scaffold in air and have enhanced image contrast. DEI was the only technique able to visualize scaffolds embedded in unstained muscle tissue; this method could also define the microstructure of muscle tissue in the boundary areas. At a photon energy of 20 KeV, DEI had the capacity to image PLLA/chitosan scaffolds in soft tissue with a sample thickness of up to 4 cm. The DEI technique can be applied at high X-ray energies, thus facilitating lower in vivo radiation doses to tissues during imaging as compared to conventional radiography.
支架可视化具有挑战性，但对于各种组织工程应用的成功至关重要。本研究旨在探索 X 射线衍射增强成像（DEI）作为一种新方法在软组织中可视化低密度工程支架的潜力。使用基于同步辐射的射线照相术、在线相衬成像（in-line PCI）和 DEI 技术以及实验室射线照相术对由聚 L-乳酸（PLLA）和壳聚糖制成的支架进行成像。支架在空气、水和大鼠肌肉组织中进行了可视化。与 X 射线射线照相术和 in-line PCI 技术的图像相比，DEI 图像更清晰地显示了低密度支架在空气中的结构，并且具有增强的图像对比度。DEI 是唯一能够可视化未染色肌肉组织中嵌入支架的技术；该方法还可以定义边界区域中肌肉组织的微观结构。在光子能量为 20keV 时，DEI 能够对软组织中的 PLLA/壳聚糖支架进行成像，样品厚度可达 4cm。与传统射线照相术相比，DEI 技术可在高 X 射线能量下应用，从而在成像过程中降低组织的体内辐射剂量。
