Raman spectroscopy for early real-time endoscopic optical diagnosis based on biochemical changes during the carcinogenesis of Barrett’s esophagus

Table 1 Comparison of two endoscopic confocal raman spectroscopic systems

Technical parameters	Developed by Almond et al[3]	Developed by Bergholt et al[4]
λex	830 nm	785 nm
Diameter of probe	2.7 mm	1.8 mm
Range of Raman spectra	400-1850 cm-1	800-1800 cm-1
Acquisition times	1 s	0.2 s
Classification model	Principal component fed linear discriminant analysis	Partial least-squares discriminant analysis[9]
Diagnostic way	Ex vivo	Real-time in vivo
Sensitivity and specificity for detecting HGD in BE	86% and 88%	87.0% and 84.7%

HGD: High grade dysplasia; BE: Barrett's esophagus.