title: Near-infrared II fluorescence for imaging hindlimb vessel regeneration with dynamic tissue perfusion measurement.
abstract: BACKGROUND
  Real-time vascular imaging that provides both anatomic and hemodynamic information could greatly facilitate the diagnosis of vascular diseases and provide accurate assessment of therapeutic effects. Here, we have developed a novel fluorescence-based all-optical method, named near-infrared II (NIR-II) fluorescence imaging, to image murine hindlimb vasculature and blood flow in an experimental model of peripheral arterial disease, by exploiting fluorescence in the NIR-II region (1000-1400 nm) of photon wavelengths.
  
  
  RESULTS
  Because of the reduced photon scattering of NIR-II fluorescence compared with traditional NIR fluorescence imaging and thus much deeper penetration depth into the body, we demonstrated that the mouse hindlimb vasculature could be imaged with higher spatial resolution than in vivo microscopic computed tomography. Furthermore, imaging during 26 days revealed a significant increase in hindlimb microvascular density in response to experimentally induced ischemia within the first 8 days of the surgery (P<0.005), which was confirmed by histological analysis of microvascular density. Moreover, the tissue perfusion in the ischemic hindlimb could be quantitatively measured by the dynamic NIR-II method, revealing the temporal kinetics of blood flow recovery that resembled microbead-based blood flowmetry and laser Doppler blood spectroscopy.
  
  
  CONCLUSIONS
  The penetration depth of millimeters, high spatial resolution, and fast acquisition rate of NIR-II imaging make it a useful imaging tool for murine models of vascular disease.
authors.affiliation: From the School of Medicine, Division of Cardiovascular Medicine (J.C.L., A.J., J.P.C., N.F.H.), Department of Pediatrics (T.C.D.), Department of Chemistry (G.H., S.D., J.T.R., A.L.A., H.D.), and Cardiovascular Institute (K.H.N., L.H., H.D., J.P.C., N.F.H.), Stanford University, CA; and Veteran Affairs Palo Alto Health Care System, Palo Alto, CA (K.H.N., L.H., N.F.H.).
authors.forename: Guosong
authors.initials: G
authors.lastname: Hong
authors.affiliation: From the School of Medicine, Division of Cardiovascular Medicine (J.C.L., A.J., J.P.C., N.F.H.), Department of Pediatrics (T.C.D.), Department of Chemistry (G.H., S.D., J.T.R., A.L.A., H.D.), and Cardiovascular Institute (K.H.N., L.H., H.D., J.P.C., N.F.H.), Stanford University, CA; and Veteran Affairs Palo Alto Health Care System, Palo Alto, CA (K.H.N., L.H., N.F.H.).
authors.forename: Jerry C
authors.initials: JC
authors.lastname: Lee
authors.affiliation: From the School of Medicine, Division of Cardiovascular Medicine (J.C.L., A.J., J.P.C., N.F.H.), Department of Pediatrics (T.C.D.), Department of Chemistry (G.H., S.D., J.T.R., A.L.A., H.D.), and Cardiovascular Institute (K.H.N., L.H., H.D., J.P.C., N.F.H.), Stanford University, CA; and Veteran Affairs Palo Alto Health Care System, Palo Alto, CA (K.H.N., L.H., N.F.H.).
authors.forename: Arshi
authors.initials: A
authors.lastname: Jha
authors.affiliation: From the School of Medicine, Division of Cardiovascular Medicine (J.C.L., A.J., J.P.C., N.F.H.), Department of Pediatrics (T.C.D.), Department of Chemistry (G.H., S.D., J.T.R., A.L.A., H.D.), and Cardiovascular Institute (K.H.N., L.H., H.D., J.P.C., N.F.H.), Stanford University, CA; and Veteran Affairs Palo Alto Health Care System, Palo Alto, CA (K.H.N., L.H., N.F.H.).
authors.forename: Shuo
authors.initials: S
authors.lastname: Diao
authors.affiliation: From the School of Medicine, Division of Cardiovascular Medicine (J.C.L., A.J., J.P.C., N.F.H.), Department of Pediatrics (T.C.D.), Department of Chemistry (G.H., S.D., J.T.R., A.L.A., H.D.), and Cardiovascular Institute (K.H.N., L.H., H.D., J.P.C., N.F.H.), Stanford University, CA; and Veteran Affairs Palo Alto Health Care System, Palo Alto, CA (K.H.N., L.H., N.F.H.).
authors.forename: Karina H
authors.initials: KH
authors.lastname: Nakayama
authors.affiliation: From the School of Medicine, Division of Cardiovascular Medicine (J.C.L., A.J., J.P.C., N.F.H.), Department of Pediatrics (T.C.D.), Department of Chemistry (G.H., S.D., J.T.R., A.L.A., H.D.), and Cardiovascular Institute (K.H.N., L.H., H.D., J.P.C., N.F.H.), Stanford University, CA; and Veteran Affairs Palo Alto Health Care System, Palo Alto, CA (K.H.N., L.H., N.F.H.).
authors.forename: Luqia
authors.initials: L
authors.lastname: Hou
authors.affiliation: From the School of Medicine, Division of Cardiovascular Medicine (J.C.L., A.J., J.P.C., N.F.H.), Department of Pediatrics (T.C.D.), Department of Chemistry (G.H., S.D., J.T.R., A.L.A., H.D.), and Cardiovascular Institute (K.H.N., L.H., H.D., J.P.C., N.F.H.), Stanford University, CA; and Veteran Affairs Palo Alto Health Care System, Palo Alto, CA (K.H.N., L.H., N.F.H.).
authors.forename: Timothy C
authors.initials: TC
authors.lastname: Doyle
authors.affiliation: From the School of Medicine, Division of Cardiovascular Medicine (J.C.L., A.J., J.P.C., N.F.H.), Department of Pediatrics (T.C.D.), Department of Chemistry (G.H., S.D., J.T.R., A.L.A., H.D.), and Cardiovascular Institute (K.H.N., L.H., H.D., J.P.C., N.F.H.), Stanford University, CA; and Veteran Affairs Palo Alto Health Care System, Palo Alto, CA (K.H.N., L.H., N.F.H.).
authors.forename: Joshua T
authors.initials: JT
authors.lastname: Robinson
authors.affiliation: From the School of Medicine, Division of Cardiovascular Medicine (J.C.L., A.J., J.P.C., N.F.H.), Department of Pediatrics (T.C.D.), Department of Chemistry (G.H., S.D., J.T.R., A.L.A., H.D.), and Cardiovascular Institute (K.H.N., L.H., H.D., J.P.C., N.F.H.), Stanford University, CA; and Veteran Affairs Palo Alto Health Care System, Palo Alto, CA (K.H.N., L.H., N.F.H.).
authors.forename: Alexander L
authors.initials: AL
authors.lastname: Antaris
authors.affiliation: From the School of Medicine, Division of Cardiovascular Medicine (J.C.L., A.J., J.P.C., N.F.H.), Department of Pediatrics (T.C.D.), Department of Chemistry (G.H., S.D., J.T.R., A.L.A., H.D.), and Cardiovascular Institute (K.H.N., L.H., H.D., J.P.C., N.F.H.), Stanford University, CA; and Veteran Affairs Palo Alto Health Care System, Palo Alto, CA (K.H.N., L.H., N.F.H.).
authors.forename: Hongjie
authors.initials: H
authors.lastname: Dai
authors.affiliation: From the School of Medicine, Division of Cardiovascular Medicine (J.C.L., A.J., J.P.C., N.F.H.), Department of Pediatrics (T.C.D.), Department of Chemistry (G.H., S.D., J.T.R., A.L.A., H.D.), and Cardiovascular Institute (K.H.N., L.H., H.D., J.P.C., N.F.H.), Stanford University, CA; and Veteran Affairs Palo Alto Health Care System, Palo Alto, CA (K.H.N., L.H., N.F.H.).
authors.forename: John P
authors.initials: JP
authors.lastname: Cooke
authors.affiliation: From the School of Medicine, Division of Cardiovascular Medicine (J.C.L., A.J., J.P.C., N.F.H.), Department of Pediatrics (T.C.D.), Department of Chemistry (G.H., S.D., J.T.R., A.L.A., H.D.), and Cardiovascular Institute (K.H.N., L.H., H.D., J.P.C., N.F.H.), Stanford University, CA; and Veteran Affairs Palo Alto Health Care System, Palo Alto, CA (K.H.N., L.H., N.F.H.). ngantina@stanford.edu.
authors.forename: Ngan F
authors.initials: NF
authors.lastname: Huang
mesh_terms: D000818:Animals; D001783:Blood Flow Velocity / Q000502:physiology; D003097:Collateral Circulation / Q000502:physiology*; D004195:Disease Models, Animal; D005260:Female; D005453:Fluorescence; D006439:Hemodynamics / Q000502:physiology; D006614:Hindlimb / Q000098:blood supply*; D007259:Infrared Rays; D051379:Mice; D008819:Mice, Nude; D055806:Microvessels / Q000502:physiology; D061848:Optical Imaging / Q000379:methods*; D058729:Peripheral Arterial Disease / Q000175:diagnosis* / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed / Q000379:methods
keywords: angiography; hemodynamics; nanotubes, carbon