Light Scattering Properties Vary across Different Regions of the Adult Mouse Brain
A: Basic experimental setup with the punch-through method. On an inverted microscope, an optical fiber was placed on a section of brain tissue such that light from the fiber would pass through the tissue and subsequently be imaged by an objective attached to a CCD camera. B: Optical transmittance as a function of tissue thickness. As the optical fiber was advanced through the section of brain tissue and repeated images such as the one in 1C were taken, the decrease in optical transmittance as a function of tissue thickness could be evaluated. The single measurements (“+” symbols) represent transmittance of blue light (453 nm) through a section of PPT at various thicknesses, while the solid line represents an exponential fit. C: An example of an original image captured by the CCD camera, showing light emitted from an optical fiber after it passed though a section of brain tissue.