This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. We have developed a novel probe that, when used in conjunction with SSFDPM, can be used to determine the optical properties of in-vivo superficial tissue. This project seeks to quantitatively characterize the probe performance and identify key parameters that impact the interrogation depth.