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Gold nanorods (with dominant absorption) were found to
provide higher contrast in tissue-like phantoms than the silica
spheres (with dominant scattering).
14.3.4 Magnetomotive OCT
A nal class of nanoparticle-based contrast for OCT is cen-
tered not on optical contrast mechanisms (as is the case with
plasmonic gold nanoparticles), but on the tiny displacements of
magnetic nanoparticles induced by an external magnetic eld.
Magnetic nanoparticles are attractive contrast agents for OCT
(Oldenburg et al. 2005, 2008, Oh et al. 2007, 2008) because they
are already FDA approved as contrast agents for MR