• We present noninvasive, quantitative in vivo measurements of methemoglobin formation and reduction in a rabbit model using broadband diffuse optical spectroscopy. Broadband DOS combines multifrequency frequency-domain photon migration with time-independent near infrared spectroscopy to quantitatively measure bulk tissue absorption and scattering spectra between 600 nm and 1,000 nm. Tissue concentrations of methemoglobin, deoxyhemoglobin, and oxyhemoglobin were determined from absorption spectra …Read more