Angular domain spectroscopic imaging (ADSI) is a hyperspectral imaging technology that combines both optical spectroscopy and optical imaging into a single platform. The technique employs an array of micro-channels to perform angular filtration, whereby quasi-ballistic photons traversing a turbid sample are accepted, and scattered photons (imagedegrading) are rejected. The aim of the work reported here was to evaluate the effectiveness of an ADSI system at identifying targets buried within tissue-mimicking phantoms. Principal component analysis (PCA) was applied to spectral data-cubes to extract the main spectral features from the images. Targets of various absorption levels (indocyanine green), depths beneath the phantom surface, and background scattering levels were evaluated. Principal components were analyzed with k-means clustering. The extracted features were grouped and classified. Then, the sensitivity and specificity of the ADSI system were estimated. Angular domain spectroscopic imaging with PCA provided clear separation of targets of different absorber concentration and depth. The results led us to conclude that the technique holds potential for characterizing tissue specimens obtained during surgery.

Date Published: 26 February 2013
PDF: 9 pages
Proc. SPIE 8579, Optical Interactions with Tissue and Cells XXIV, 85790N (26 February 2013); doi: 10.1117/12.2004551

Published in SPIE Proceedings Vol. 8579:
Optical Interactions with Tissue and Cells XXIV
E. Duco Jansen; Robert J. Thomas, Editor(s)