Copyright ©The Author(s) 2016.
World J Gastrointest Oncol. May 15, 2016; 8(5): 427-438
Published online May 15, 2016. doi: 10.4251/wjgo.v8.i5.427
Table 1 A comparison of Raman spectroscopy, fourier transform infrared spectroscopy and hematoxylin and eosin staining strengths and weaknesses
Raman spectroscopyFTIRHematoxylin and eosin staining
Method of detectionInelastic scattering of monochromatic (laser) lightAbsorbance (polychromatic light source)Combination of basic and acidic dyes
Real timeYesYesNo
Wavenumber range (cm-1)50-4000400-4000N/A
Spatial resolution1 μm5 μmCellular
Enhancement techniquesSERS, TERS, CARS, SORS, SRSATR"Special" staining
Effect of waterMinimalLarge absorbance in NIR regionNo
Destructive to sampleNoNoYes
Table 2 A summary of the different clinical applications of Raman spectroscopy to colorectal cancer
MethodSampling typeSample numberRef.YearSpectral region (cm-1)Laser excitation (nm)Data analysis
ProbeIn vivo (tissue)20Shim et al[42]2000450-1800785PCA, PLS, ANN
ProbeIn vivo and ex vivo (tissue)9Molckovsky et al[44]2003900-1800785PCA, LDA, LOOCV
Micro-spectrometerIn vitro (primary tissue)10Chen et al[38]2006500-1900782.5PCA
ProbeEx vivo (tissue)59Widjaja et al[45]2008800-1800785PCA, SVM, LOOCV
Micro-spectrometerEx vivo (tissue)54Beljebbar et al[47]2009600-1800785SVM, PCA
Micro-spectrometerIn vitro (serum)120Li et al[37]2012800-1800785PCR, PLSR, LDA
Micro-spectrometerIn vitro (cell lines)N/ARanc et al[39]2013400-1800532PCA
ProbeIn vitro (tissue)177Wood et al[43]2014800-1800830PCA, LDA, LOOCV
Micro-spectrometerIn vivo (tissue)50Bergholt et al[78]2014800-1800 and 2900-3600785PLS, LDA