title: Combined fluorescence and X-Ray tomography for quantitative in vivo detection of fluorophore.
abstract: Initial results from a novel dual modality preclinical imager which combines non-contact fluorescence tomography (FT) and x-ray computed tomography (CT) for preclinical functional and anatomical in vivo imaging are presented. The anatomical data from CT provides a priori information to the FT reconstruction to create overlaid functional and anatomical images with accurate localization and quantification of fluorophore distribution. Phantoms with inclusions containing Indocyanine-Green (ICG), and with heterogeneous backgrounds including iodine in compartments at different concentrations for CT contrast, have been imaged with the dual modality FT/CT system. Anatomical information from attenuation maps and optical morphological information from absorption and scattering maps are used as a priori information in the FT reconstruction. Although ICG inclusions can be located without the a priori information, the recovered ICG concentration shows 75% error. When the a priori information is utilized, the ICG concentration can be recovered with only 15% error. Developing the ability to accurately quantify fluorophore concentration in anatomical regions of interest may provide a powerful tool for in vivo small animal imaging.
authors.affiliation: DxRay Inc., 19355 Business Center Dr. Suite 10, Northridge, CA 91324, USA. William.barber@dxray.com
authors.forename: W C
authors.initials: WC
authors.lastname: Barber
authors.forename: Y
authors.initials: Y
authors.lastname: Lin
authors.forename: O
authors.initials: O
authors.lastname: Nalcioglu
authors.forename: J S
authors.initials: JS
authors.lastname: Iwanczyk
authors.forename: N E
authors.initials: NE
authors.lastname: Hartsough
authors.forename: G
authors.initials: G
authors.lastname: Gulsen
mesh_terms: D000891:Anti-Infective Agents, Local; D004396:Coloring Agents; D005453:Fluorescence; D005456:Fluorescent Dyes; D006801:Humans; D007208:Indocyanine Green; D007455:Iodine; D019047:Phantoms, Imaging; D014054:Tomography / Q000295:instrumentation / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000295:instrumentation* / Q000379:methods*
chemical_list: D000891:Anti-Infective Agents, Local; D004396:Coloring Agents; D005456:Fluorescent Dyes; D007455:Iodine; D007208:Indocyanine Green