Transcutaneous Raman spectroscopy of bone global sampling and ring/disk fiber optic probes

摘要

We have used fiber optic probes with global illumination/collection (PhAT probe, Kaiser Optical Systems) and ring illumination/disk collection configurations for transcutaneous Raman spectroscopy of bone tissue. Both illumination/collection schemes can be used for recovery of spectra of subsurface components. In this paper the global illumination configuration provides minimum local power density and so minimizes the probability of damage to specimens, animals or human subjects. It also allows non-destructive subsurface mapping under certain conditions. The ring/disk probe utilizes a ring of laser light and collects Raman scatter from within the diameter of the ring. This design distributes the laser power for efficient heat dissipation and provides a better collection ratio of subsurface to surface components than the global illumination design. For non-invasive tissue spectroscopy the ring/disk design also provides better rejection of fluorescence from melanocytes. We have tested the performance of these Raman probes on polymer model systems and chicken tibiae.