Figure 1.
Principles of in vivo multiparametric imaging with optical frequency domain imaging (OFDI). (a) An optical beam is focused into the tissue. The light reflected across all depths is combined with a reference beam and the interference signal is recorded as a function of light wavelength from 1,220 nm to 1,360 nm. The amplitude and phase of the reflected light as a function of wavelength is used to localize the reflected signal as a function of depth. At a given depth, the amplitude and phase of the reflected signal as a function of time is used to derive the optical scattering properties and thereby the tissue structure and function.(b) The depth-projected vasculature within the first 2 mm of mouse brain bearing a xenotransplanted U87 human glioblastoma multiforme tumor imaged with OFDI. Depth is denoted by color: yellow (superficial) to red (deep). Scale bar, 500 μm.