title: Laser tissue coagulation and concurrent optical coherence tomography through a double-clad fiber coupler.
abstract: Double-clad fiber (DCF) is herein used in conjunction with a double-clad fiber coupler (DCFC) to enable simultaneous and co-registered optical coherence tomography (OCT) and laser tissue coagulation. The DCF allows a single channel fiber-optic probe to be shared: i.e. the core propagating the OCT signal while the inner cladding delivers the coagulation laser light. We herein present a novel DCFC designed and built to combine both signals within a DCF (>90% of single-mode transmission; >65% multimode coupling). Potential OCT imaging degradation mechanisms are also investigated and solutions to mitigate them are presented. The combined DCFC-based system was used to induce coagulation of an ex vivo swine esophagus allowing a real-time assessment of thermal dynamic processes. We therefore demonstrate a DCFC-based system combining OCT imaging with laser coagulation through a single fiber, thus enabling both modalities to be performed simultaneously and in a co-registered manner. Such a system enables endoscopic image-guided laser marking of superficial epithelial tissues or laser thermal therapy of epithelial lesions in pathologies such as Barrett's esophagus.
authors.affiliation: Centre d'Optique Photonique et Lasers, Polytechnique Montreal, Department of Engineering Physics, Montreal, QC H3C 3A7, Canada ; Wellman Center for Photomedicine, Harvard Medical School and Massachusetts General Hospital, Boston, Massachusetts 02114, USA.
authors.forename: Kathy
authors.initials: K
authors.lastname: Beaudette
authors.affiliation: Wellman Center for Photomedicine, Harvard Medical School and Massachusetts General Hospital, Boston, Massachusetts 02114, USA ; School of Electronic and Electrical Engineering, Sungkyunkwan University, Suwon, South Korea.
authors.forename: Hyoung Won
authors.initials: HW
authors.lastname: Baac
authors.affiliation: Centre d'Optique Photonique et Lasers, Polytechnique Montreal, Department of Engineering Physics, Montreal, QC H3C 3A7, Canada.
authors.forename: Wendy-Julie
authors.initials: WJ
authors.lastname: Madore
authors.affiliation: Wellman Center for Photomedicine, Harvard Medical School and Massachusetts General Hospital, Boston, Massachusetts 02114, USA.
authors.forename: Martin
authors.initials: M
authors.lastname: Villiger
authors.affiliation: Centre d'Optique Photonique et Lasers, Polytechnique Montreal, Department of Engineering Physics, Montreal, QC H3C 3A7, Canada.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Godbout
authors.affiliation: Wellman Center for Photomedicine, Harvard Medical School and Massachusetts General Hospital, Boston, Massachusetts 02114, USA ; Harvard-Massachusetts Institute of Technology, Program in Health Sciences and Technology, Cambridge, Massachusetts 02142, USA.
authors.forename: Brett E
authors.initials: BE
authors.lastname: Bouma
authors.affiliation: Centre d'Optique Photonique et Lasers, Polytechnique Montreal, Department of Engineering Physics, Montreal, QC H3C 3A7, Canada.
authors.forename: Caroline
authors.initials: C
authors.lastname: Boudoux
keywords: (060.2340) Fiber optics components; (170.2150) Endoscopic imaging; (170.3880) Medical and biological imaging; (170.3890) Medical optics instrumentation; (170.4500) Optical coherence tomography