Hyperspectral imaging of atherosclerotic plaques in vitro

Abstract

Vulnerable plaques constitute a risk for serious heart problems, and are difficult to identify using existing methods. Hyperspectral imaging combines spectral- and spatial information, providing new possibilities for precise optical characterization of atherosclerotic lesions. Hyperspectral data were collected from excised aorta samples (n = 11) using both white-light and ultraviolet illumination. Single lesions (n = 42) were chosen for further investigation, and classified according to histological findings. The corresponding hyperspectral images were characterized using statistical image analysis tools (minimum noise fraction, K-means clustering, principal component analysis) and evaluation of reflectance/fluorescence spectra. Image analysis combined with histology revealed the complexity and heterogeneity of aortic plaques. Plaque features such as lipids and calcifications could be identified from the hyperspectral images. Most of the advanced lesions had a central region surrounded by an outer rim or shoulder-region of the plaque, which is considered a weak spot in vulnerable lesions. These features could be identified in both the white-light and fluorescence data. Hyperspectral imaging was shown to be a promising tool for detection and characterization of advanced atherosclerotic plaques in vitro. Hyperspectral imaging provides more diagnostic information about the heterogeneity of the lesions than conventional single point spectroscopic measurements.

Estimation of skin optical parameters for real-time hyperspectral imaging applications

“…1,2 This makes it a promising tool for tissue characterization and optical diagnostics. 1,3,4 Flexible wide-field imaging options give the possibility of rapid scanning of both larger areas and samples and smaller details, e.g., full body scans and close up imaging with microscopic resolution. 5 The physical size of the equipment makes it possible to place it on a small trolley, and it can thus be used for bedside scanning.…”

Optimization of wavelength selection for multispectral image acquisition: a case study of atrial ablation lesions

“…The results presented here, can benefit the two major classes of spectral imagers, i.e, scanning and snapshot based systems. In scanning systems that use acousto-optical tunable filters [37,38], line-scanning [39], point-by-point scanning [40] or liquid tunable filters [26], decreasing the number of bands needed, results in faster scans for the same spatial resolution. Faster acquisition times in such systems can also be achieved through narrowing the range of acquisition while maintaining the same spectral resolution as detailed in section 3.2 and Fig.…”

Review of spectral imaging technology in biomedical engineering: achievements and challenges

“…236 Larsen et al presented the hyperspectral image analysis combined with the histology method for detection and characterization of advanced atherosclerotic plaques in vitro. 237 Maeder et al introduced a confocal laser-scanning microscope equipped with a detection unit that provides high spectral resolution method to visualize and evaluate the spatial distribution of spectral information in skin sections. 221 In a more recent study by Nallala et al, an IR spectral imaging system was used for histopathological recognition in colon cancer diagnosis.…”