Observation of Atherosclerotic Plaque Phantoms through Saline or Blood Layers by Near-Infrared Hyperspectral Imaging

Abstract

We observed atherosclerotic plaque phantoms using a novel near-infrared (NIR) hyperspectral imaging (HSI) technique. Data were obtained through saline or blood layers to simulate an angioscopic environment for the phantom. For the study, we developed a NIR-HSI system with an NIR supercontinuum light source and mercury-cadmium-telluride camera. Apparent spectral absorbance was obtained at wavelengths of 1150 -2400 nm. Hyperspectral images of lipid were constructed using a spectral angle mapper algorithm. Bovine fat covered with saline or blood was observed using hyperspectral images at a wavelength around 1200 nm. Our results show that NIR-HSI is a promising angioscopic technique with the potential to identify lipid-rich plaques without clamping and saline injection.

Application of near-infrared hyperspectral imaging to discriminate different geographical origins of Chinese wolfberries

“…The absorption peak near 995 nm was attributed to the second vibration of N-H bonds in proteins or amino acids [ 30 – 31 ]. The absorption peak near 1200 nm was attributed to the secondary stretching vibration of C-H bonds in starch, proteins or lipids [ 32 – 33 ]. The absorption peak near 1465 nm was the sensitive region for water absorption [ 34 ].…”

Quantitative Evaluation of Lipid Volume Fraction in Atherosclerotic Plaque Phantoms by Near-infrared Multispectral Imaging at Wavelengths around 1200 nm

“…To apply MSI to angioscopy, it is necessary to consider the effects of blood and the saline ush used in the intravascular environment. The spectral band around 1200 nm has good optical penetration for water and hemoglobin, and the atherosclerotic phantoms could be observed under saline at a depth of 10 mm or under arterial blood at a depth of 1 mm in our previous research [19]. NIR-MSI at 1200 nm is potentially capable of evaluating plaques through saline when used with an angioscope, because the focus of the angioscope is around 2 mm.…”

“…The phantoms were observed through saline or blood layers, using the NIR-MSI system at wavelengths around 1200, 1700, and 2300 nm. In saline and blood environments, wavelengths around 1200 nm were optimal for lipid detection [19]. However, quantitative evaluation of lipid volume fraction to characterize plaque types had not been performed.…”