Ahmed Rafay, Law Alan Wing Lun, Cheung Tsz Wing, Lau Condon
Department of Physics, The City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong Special Administrative Region, China.
Biomed Opt Express. 2018 Mar 14;9(4):1704-1716. doi: 10.1364/BOE.9.001704. eCollection 2018 Apr 1.
Subcritical calvarial defects heal spontaneously and optical methods can study the healing without mechanically perturbing the bone. In this study, 1mm defects were created on the skulls (in vivo) of Sprague-Dawley rats (n = 14). After 7 (n = 7) and 14 days (n = 7) of healing, the subjects were sacrificed and additional defects were similarly created (control). Raman spectroscopy (785nm) was performed at the two time points and defect types. Spectra were quantified by the mineral/matrix ratio, carbonate/phosphate ratio and crystallinity. Mineral/matrix of in vivo defects is lower than that of controls by ~34% after 7 days and ~21% after 14 days. Carbonate/phosphate is 8% and 5% higher while crystallinity is 7% and 3% lower, respectively. Optical profiling shows that the surface roughness increases 1.2% from controls to in vivo after 7 days, then decreases 13% after 14 days. Overall, the results show maturation of mineral crystals during healing and agree with microscopic assessment.
亚临界颅骨缺损可自发愈合，光学方法能够在不对骨骼造成机械干扰的情况下研究其愈合过程。在本研究中，在斯普拉格-道利大鼠（n = 14）的颅骨（活体）上制造了1毫米的缺损。在愈合7天（n = 7）和14天（n = 7）后，处死实验对象并制造同样的缺损（对照）。在两个时间点和两种缺损类型上进行了拉曼光谱分析（785纳米）。通过矿物质/基质比、碳酸盐/磷酸盐比和结晶度对光谱进行定量分析。活体缺损的矿物质/基质在7天后比对照低约34%，在14天后低约21%。碳酸盐/磷酸盐分别高出8%和5%，而结晶度分别低7%和3%。光学轮廓分析表明，表面粗糙度在7天后从对照到活体增加了1.2%，在14天后降低了13%。总体而言，结果显示愈合过程中矿物质晶体的成熟，与微观评估结果一致。
