Evans blue dye-enhanced imaging of the brain microvessels using spectral focusing coherent anti-Stokes Raman scattering microscopy

PLoS One. 2017 Oct 19;12(10):e0185519. doi: 10.1371/journal.pone.0185519. eCollection 2017.

Abstract

We performed dye-enhanced imaging of mouse brain microvessels using spectral focusing coherent anti-Stokes Raman scattering (SF-CARS) microscopy. The resonant signals from C-H stretching in forward CARS usually show high background intensity in tissues, which makes CARS imaging of microvessels difficult. In this study, epi-detection of back-scattered SF-CARS signals showed a negligible background, but the overall intensity of resonant CARS signals was too low to observe the network of brain microvessels. Therefore, Evans blue (EB) dye was used as contrasting agent to enhance the back-scattered SF-CARS signals. Breakdown of brain microvessels by inducing hemorrhage in a mouse was clearly visualized using backward SF-CARS signals, following intravenous injection of EB. The improved visualization of brain microvessels with EB enhanced the sensitivity of SF-CARS, detecting not only the blood vessels themselves but their integrity as well in the brain vasculature.

MeSH terms

  • Animals
  • Brain / blood supply*
  • Evans Blue
  • Intracranial Hemorrhages / diagnostic imaging
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Microscopy / methods*
  • Microvessels / diagnostic imaging*
  • Spectrum Analysis, Raman / methods*

Substances

  • Evans Blue

Grants and funding

This research was supported by the research programs of DGIST (17-BT-01, 17-BT-02, 17-BD-06, and 17-01-HRMA-02) funded by the Ministry of Science, ICT, and Future Planning of Korea. It was also supported by the research program 2016R1A2B4014728 funded by the Ministry of Science, ICT, and Future Planning of Korea. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.