Selective detection of fluorophore layers in turbid media: the role of fiber-optic probe design.

Experimental verification of the ability to alter the sensitivity to fluorophore layers in turbid media by varying illumination-collection geometry is presented. Fiber-optic probes and two-layer, fluorophore-doped, turbid phantoms are used to elucidate the roles of spot size, illumination-collection fiber separation, and probe-sample spacing. Variations in single- and multiple-fiber probe design parameters produce significant changes in the relative sensitivity to sample layers in a manner that agrees with prior computational studies.