title: Effects of fiber-optic probe design and probe-to-target distance on diffuse reflectance measurements of turbid media: an experimental and computational study at 337 nm.
abstract: Fiber-optic probes are widely used in optical spectroscopy of biological tissues and other turbid media. Only limited information exists, however, on the ways in which the illumination-collection geometry and the overall probe design influence the interrogation of media. We have investigated both experimentally and computationally the effect of probe-to-target distance (PTD) on the diffuse reflectance collected from an isotropically (Lambertian) scattering target and an agar-based tissue phantom. Studies were conducted with three probes characterized by either common (single-fiber) or separate (two bifurcated multifiber probes) illumination and collection channels. This study demonstrates that PTD, probe design, and tissue scattering anisotropy influence the extent of the transport of light into the medium, the light-collection efficiency, and the sampling volume of collected light. The findings can be applied toward optimization of fiber-optic probe designs for quantitative optical spectroscopy of turbid media including biological tissues.
authors.affiliation: Biophotonics Research and Technology Development, Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, California 90048, USA.
authors.forename: Thanassis
authors.initials: T
authors.lastname: Papaioannou
authors.forename: Norris W
authors.initials: NW
authors.lastname: Preyer
authors.forename: Qiyin
authors.initials: Q
authors.lastname: Fang
authors.forename: Adam
authors.initials: A
authors.lastname: Brightwell
authors.forename: Michael
authors.initials: M
authors.lastname: Carnohan
authors.forename: Greg
authors.initials: G
authors.lastname: Cottone
authors.forename: Russel
authors.initials: R
authors.lastname: Ross
authors.forename: Linda R
authors.initials: LR
authors.lastname: Jones
authors.forename: Laura
authors.initials: L
authors.lastname: Marcu
mesh_terms: D003198:Computer Simulation; D017076:Computer-Aided Design; D003238:Connective Tissue / Q000378:metabolism / Q000648:ultrastructure; D004867:Equipment Design / Q000379:methods; D019544:Equipment Failure Analysis / Q000379:methods*; D005336:Fiber Optic Technology / Q000295:instrumentation*; D008856:Microscopy, Fluorescence / Q000295:instrumentation* / Q000379:methods; D008860:Microscopy, Ultraviolet / Q000295:instrumentation* / Q000379:methods; D008954:Models, Biological; D055100:Optical Fibers; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000295:instrumentation* / Q000379:methods; D013056:Spectrophotometry, Ultraviolet / Q000295:instrumentation* / Q000379:methods; D014159:Transducers