Biophotonic methods in microcirculation imaging

Visible and near-infrared light, particularly in the wavelength region of 600–1100 nm, offer a window into human and animal tissues due to reduced scattering and absorption. We review the main biophotonic methods applied to visualisation and assessment of the microcirculation and document the progress made over the past 10 years in particular. Applications, particularly in human skin, are of special topical importance due to an improved knowledge of its role and its value as a surrogate for other organs in drug testing at a time when drug development is under severe pressure.