Lipid concentrations in human coronary artery determined with high wavenumber Raman shifted light

Raman spectroscopy is a rapid nondestructive technique capable of assaying chemicals in human artery tissues and characterizing atherosclerotic plaques in vivo, but clinical applications through optical fiber-based catheters have been hindered by large background signals generated within the fibers. Previous workers realized that this background was reduced significantly in the high wavenumber (HWVN) Raman region ( approximately 2,400 cm(-1) to approximately 3,800 cm(-1)), and with proper selection of optical fibers, one could collect quality Raman spectra remotely via a single optical fiber with no additional filters or optics. This study compared lipid concentrations in coronary artery tissue that were determined with chemical assay techniques to those estimated from HWVN Raman spectra collected through a single optical fiber. The standard error of predictions between the Raman and chemical assay techniques were small for cholesterol and esterified cholesterols, at 1.2% and 2.7%, respectively.