Department of Internal Medicine, Rheumatology Division, University of Michigan Medical School, Medical Science Research Building II, 1150 West Medical Center Drive, Room 3560, Ann Arbor, MI 48109-5688, USA.
Analyst. 2011 Apr 21;136(8):1675-85. doi: 10.1039/c0an00824a. Epub 2011 Feb 28.
In this study, we report adaptation of Raman spectroscopy for arthroscopy of joint tissues using a custom-built fiber-optic probe. Differentiation of healthy and damaged tissue or examination of subsurface tissue, such as subchondral bone, is a challenge in arthroscopy because visual inspection may not provide sufficient contrast. Discrimination of healthy versus damaged tissue may be improved by incorporating point spectroscopy or hyperspectral imaging into arthroscopy where the contrast is based on the molecular structure or chemical composition. Articular joint surfaces of knee cadaveric human tissue and tissue phantoms were examined using a custom-designed Raman fiber-optic probe. Fiber-optic Raman spectra were compared against reference spectra of cartilage, subchondral bone and cancellous bone collected using Raman microspectroscopy. In fiber-optic Raman spectra of the articular surface, there was an effect of cartilage thickness on recovery of signal from subchondral bone. At sites with intact cartilage, the bone mineralization ratio decreased but there was a minimal effect in the bone mineral chemistry ratios. Tissue phantoms were prepared as experimental models of the osteochondral interface. Raman spectra of tissue phantoms suggested that optical scattering of cartilage has a large effect on the relative cartilage and bone signal. Finite element analysis modeling of light fluence in the osteochondral interface confirmed experimental findings in human cadaveric tissue and tissue phantoms. These first studies demonstrate the proof of principle for Raman arthroscopic measurement of joint tissues and provide a basis for future clinical or animal model studies.
在这项研究中，我们报告了使用定制光纤探头对关节组织关节镜检查中的拉曼光谱进行适配。由于肉眼检查可能无法提供足够的对比度，因此区分健康组织和受损组织或检查亚表面组织（如软骨下骨）是关节镜检查中的一个挑战。通过将点光谱或高光谱成像技术纳入关节镜检查中，可以改善健康组织与受损组织的区分，其对比度基于分子结构或化学成分。使用定制设计的拉曼光纤探头检查了膝关节尸体人组织和组织体模的关节表面。将光纤拉曼光谱与使用拉曼微光谱收集的软骨、软骨下骨和松质骨的参考光谱进行了比较。在关节表面的光纤拉曼光谱中，软骨厚度对软骨下骨信号的恢复有影响。在软骨完整的部位，骨矿化率降低，但骨矿化学比率的影响最小。组织体模被制备为骨软骨界面的实验模型。组织体模的拉曼光谱表明，软骨的光散射对相对软骨和骨信号有很大影响。骨软骨界面光通量的有限元分析模型证实了人体尸体组织和组织体模中的实验结果。这些初步研究证明了用于关节组织的拉曼关节镜测量的原理证明，并为未来的临床或动物模型研究提供了基础。
