title: Dual modality instrument for simultaneous optical coherence tomography imaging and fluorescence spectroscopy.
abstract: We develop a dual-modality device that combines the anatomical imaging capabilities of optical coherence tomography (OCT) with the functional capabilities of laser-induced fluorescence (LIF) spectroscopy. OCT provides cross-sectional images of tissue structure to a depth of up to 2 mm with approximately 10-microm resolution. LIF spectroscopy provides histochemical information in the form of emission spectra from a given tissue location. The OCT subsystem utilizes a superluminescent diode with a center wavelength of 1300 nm, whereas a helium cadmium laser provides the LIF excitation source at wavelengths of 325 and 442 nm. Preliminary data are obtained on eight postmortem aorta samples, each 10 mm in length. OCT images and LIF spectra give complementary information from normal and atherosclerotic portions of aorta wall. OCT images show structures such as intima, media, internal elastic lamina, and fibrotic regions. Emission spectra ratios of 520/490 (325-nm excitation) and 595/635 (442-nm excitation) could be used to identify normal and plaque regions with 97 and 91% correct classification rates, respectively. With miniaturization of the delivery probe and improvements in system speed, this dual-modality device could provide a valuable tool for identification and characterization of atherosclerotic plaques.
authors.affiliation: Electrical & Computer Engineering Department, Division of Biomedical Engineering, University of Arizona, 1501 N Campbell, PO Box 245084, Tucson, AZ 85724, USA. barton@u.arizona.edu
authors.forename: Jennifer Kehlet
authors.initials: JK
authors.lastname: Barton
authors.forename: Francisco
authors.initials: F
authors.lastname: Guzman
authors.forename: Alexandre
authors.initials: A
authors.lastname: Tumlinson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001011:Aorta / Q000378:metabolism* / Q000473:pathology*; D015925:Cryopreservation / Q000379:methods; D046508:Culture Techniques; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D006454:Hemoglobins / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000379:methods; D013050:Spectrometry, Fluorescence / Q000295:instrumentation* / Q000379:methods; D018511:Systems Integration; D041623:Tomography, Optical Coherence / Q000295:instrumentation* / Q000379:methods
chemical_list: D006454:Hemoglobins