title: Spatial refractive index measurement of porcine artery using differential phase optical coherence microscopy.
abstract: OBJECTIVE
  We describe a methodology to record spatial variation of refractive index of porcine renal artery using differential phase optical coherence microscopy (DP-OCM).
  
  
  METHODS
  The DP-OCM provides quantitative measurement of thin specimen phase retardation and refractive index by measuring optical path-length changes on the order of a few nanometers and with a lateral resolution of 3 microm. The DP-OCM instrumentation is an all-fiber, dual-channel Michelson interferometer constructed using a polarization maintaining (PM) fiber.
  
  
  RESULTS
  Two-dimensional en face dual-channel phase images are taken over a 150 x 200 microm region on a microscopic slide, and the images are reconstructed by plotting a two-dimensional refractive index map as the OCM beam is moved across the sample.
  
  
  CONCLUSIONS
  Because the DP-OCM can record transient changes in the optical path-length, the system may be used to record quantitative optical path-length alterations of tissue in response to various stimuli. A fiber-based DP-OCM may have the potential to substantially improve in vivo imaging of individual cells for a variety of clinical diagnostics, and monitoring applications.
authors.affiliation: Beckman Laser Institute, University of California, Irvine, California, USA. jeehk@uci.edu
authors.forename: Jeehyun
authors.initials: J
authors.lastname: Kim
authors.forename: Digant P
authors.initials: DP
authors.lastname: Davé
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Rylander
authors.forename: Junghwan
authors.initials: J
authors.lastname: Oh
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Milner
mesh_terms: D000818:Animals; D004549:Elastin; D008858:Microscopy, Phase-Contrast / Q000379:methods; D012077:Renal Artery / Q000033:anatomy & histology*; D013552:Swine; D041623:Tomography, Optical Coherence / Q000379:methods*
chemical_list: D004549:Elastin