Systems and methods are provided for probing an occluded body lumen, including a flexible conduit insertable into the body lumen, at least one delivery waveguide and at least one collection waveguide integrated with the flexible conduit and arranged to deliver and collect radiation about a distal end of said flexible conduit, at least one radiation source connected to a transmission input of the at least one delivery waveguide, at least one optical detector connected to a transmission output of at least one collection waveguide, a spectrometer connected with the at least one optical detector, and constructed and arranged to scan radiation and perform spectroscopy, and a controller programmed to process data from said spectrometer and provide information for directing said flexible conduit through obstacles within the occluded body lumen.