Open AccessPolarization state studies in second harmonic generation signals to trace atherosclerosis lesions
Author(s) -
Camille Doras,
Grégory Taupier,
Alberto Barsella,
Loı̈c Mager,
Alex Boeglin,
Hervé Bulou,
Pascal Bousquet,
Kokou D. Dorkenoo
Publication year - 2011
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.19.015062
Subject(s) - polarization (electrochemistry) , optics , second harmonic generation , materials science , ascending aorta , photon , aorta , physics , chemistry , medicine , laser
We have performed multi-photon image reconstructions as well as polarization state analyses inside an artery wall affected by atherosclerosis to investigate the changes in collagen structure. Mice, either healthy or affected by spontaneous atherosclerosis, have been used for this purpose. A two-photon imaging system has been used to investigate atherosclerotic lesions in the ascending aorta of mice. Second harmonic imaging has been performed alternatively on healthy samples and on affected region. The reconstructed images show that the spatial distribution of the collagen network seems disorganized by the disease. The polarization state studies reveal however that the apparent disorganization of the collagen is related to its spatially diffuse distribution and that the internal structure of the collagen fibers is not affected by the disease. In addition, a theoretical simulation of the second harmonic polarization states shows that they are consistent with the known 3D structure of the collagen network.