title: Rotational multispectral fluorescence lifetime imaging and intravascular ultrasound: bimodal system for intravascular applications.
abstract: We report the development and validation of a hybrid intravascular diagnostic system combining multispectral fluorescence lifetime imaging (FLIm) and intravascular ultrasound (IVUS) for cardiovascular imaging applications. A prototype FLIm system based on fluorescence pulse sampling technique providing information on artery biochemical composition was integrated with a commercial IVUS system providing information on artery morphology. A customized 3-Fr bimodal catheter combining a rotational side-view fiberoptic and a 40-MHz IVUS transducer was constructed for sequential helical scanning (rotation and pullback) of tubular structures. Validation of this bimodal approach was conducted in pig heart coronary arteries. Spatial resolution, fluorescence detection efficiency, pulse broadening effect, and lifetime measurement variability of the FLIm system were systematically evaluated. Current results show that this system is capable of temporarily resolving the fluorescence emission simultaneously in multiple spectral channels in a single pullback sequence. Accurate measurements of fluorescence decay characteristics from arterial segments can be obtained rapidly (e.g., 20 mm in 5 s), and accurate co-registration of fluorescence and ultrasound features can be achieved. The current finding demonstrates the compatibility of FLIm instrumentation with in vivo clinical investigations and its potential to complement conventional IVUS during catheterization procedures.
authors.affiliation: University of California, Department of Biomedical Engineering, 451 Health Sciences Drive, Davis, California 95616.
authors.forename: Dinglong
authors.initials: D
authors.lastname: Ma
authors.affiliation: University of California, Department of Biomedical Engineering, 451 Health Sciences Drive, Davis, California 95616.
authors.forename: Julien
authors.initials: J
authors.lastname: Bec
authors.affiliation: University of California, Department of Biomedical Engineering, 451 Health Sciences Drive, Davis, California 95616bUniversity of California, Department of Electrical Engineering, 3101 Kemper Hall, Davis, California 95616.
authors.forename: Diego R
authors.initials: DR
authors.lastname: Yankelevich
authors.affiliation: University of California, Department of Biomedical Engineering, 451 Health Sciences Drive, Davis, California 95616.
authors.forename: Dimitris
authors.initials: D
authors.lastname: Gorpas
authors.affiliation: University of California, Department of Biomedical Engineering, 451 Health Sciences Drive, Davis, California 95616.
authors.forename: Hussain
authors.initials: H
authors.lastname: Fatakdawala
authors.affiliation: University of California, Department of Biomedical Engineering, 451 Health Sciences Drive, Davis, California 95616.
authors.forename: Laura
authors.initials: L
authors.lastname: Marcu
mesh_terms: D000818:Animals; D001331:Automation; D002138:Calibration; D002404:Catheterization / Q000295:instrumentation* / Q000379:methods; D057785:Catheters; D003331:Coronary Vessels / Q000473:pathology*; D004452:Echocardiography; D004867:Equipment Design; D005336:Fiber Optic Technology; D005453:Fluorescence; D006321:Heart; D006801:Humans; D007091:Image Processing, Computer-Assisted; D023421:Models, Animal; D061848:Optical Imaging / Q000379:methods*; D055095:Optics and Photonics; D015203:Reproducibility of Results; D013552:Swine; D018084:Ultrasonography, Interventional / Q000379:methods*