Dual-wavelength photothermal optical coherence tomography for imaging microvasculature blood oxygen saturation

J Biomed Opt. 2013 May;18(5):56005. doi: 10.1117/1.JBO.18.5.056005.


A swept-source dual-wavelength photothermal (DWP) optical coherence tomography (OCT) system is demonstrated for quantitative imaging of microvasculature oxygen saturation. DWP-OCT is capable of recording three-dimensional images of tissue and depth-resolved phase variation in response to photothermal excitation. A 1,064-nm OCT probe and 770-nm and 800-nm photothermal excitation beams are combined in a single-mode optical fiber to measure microvasculature hemoglobin oxygen saturation (SO(2)) levels in phantom blood vessels with a range of blood flow speeds (0 to 17 mm/s). A 50-μm-diameter blood vessel phantom is imaged, and SO(2) levels are measured using DWP-OCT and compared with values provided by a commercial oximeter at various blood oxygen concentrations. The influences of blood flow speed and mechanisms of SNR phase degradation on the accuracy of SO(2) measurement are identified and investigated.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Microvessels / physiology*
  • Models, Cardiovascular
  • Oximetry / methods*
  • Oxygen / blood*
  • Oxyhemoglobins / chemistry
  • Phantoms, Imaging
  • Signal Processing, Computer-Assisted*
  • Signal-To-Noise Ratio
  • Tomography, Optical Coherence / methods*


  • Oxyhemoglobins
  • Oxygen