title: Intravascular laser speckle imaging catheter for the mechanical evaluation of the arterial wall.
abstract: Laser speckle imaging (LSI) is a novel technique for measuring the mechanical properties of atherosclerotic plaques. In LSI, the decorrelation time constant of speckle intensity fluctuations provides an index of viscoelasticity that is closely related to plaque microstructure and composition. Here, we demonstrate for the first time, the feasibility of conducting LSI in vivo using a prototype 1.5 mm (4.5 Fr) diameter intravascular catheter. Investigation of the catheter performance using human arterial samples ex vivo shows that plaque time constants measured by the LSI catheter correlate well with those measured using a free-space bulk optics system. To demonstrate LSI in vivo, the catheter is interfaced with a portable console for intravascular evaluation in the aorta of a living rabbit. Distinct differences in arterial time constants are identified at normal aortic and stented sites in vivo with intravascular LSI.
authors.affiliation: Massachusetts General Hospital, Wellman Center for Photomedicine, Harvard Medical School, Boston, Massachusetts 02114, USA.
authors.forename: Zeinab
authors.initials: Z
authors.lastname: Hajjarian
authors.forename: Jingqun
authors.initials: J
authors.lastname: Xi
authors.forename: Farouc A
authors.initials: FA
authors.lastname: Jaffer
authors.forename: Guillermo J
authors.initials: GJ
authors.lastname: Tearney
authors.forename: Seemantini K
authors.initials: SK
authors.lastname: Nadkarni
mesh_terms: D001011:Aorta / Q000000981:diagnostic imaging* / Q000502:physiology*; D057785:Catheters; D055119:Elastic Modulus / Q000502:physiology; D054459:Elasticity Imaging Techniques / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D066298:In Vitro Techniques; D007834:Lasers