Speckle variance detection of microvasculature using swept-source optical coherence tomography.
We report on imaging of microcirculation by calculating the speckle variance of optical coherence tomography (OCT) structural images acquired using a Fourier domain mode-locked swept-wavelength laser. The algorithm calculates interframe speckle variance in two-dimensional and three-dimensional OCT data sets and shows little dependence to the Doppler angle ranging from 75 degrees to 90 degrees . We demonstrate in vivo detection of blood flow in vessels as small as 25 microm in diameter in a dorsal skinfold window chamber model with direct comparison with intravital fluorescence confocal microscopy. This technique can visualize vessel-size-dependent vascular shutdown and transient vascular occlusion during Visudyne photodynamic therapy and may provide opportunities for studying therapeutic effects of antivascular treatments without on exogenous contrast agent.
Mariampillai
Adrian
A
Department of Medical Biophysics, University of Toronto, Toronto, M5G 2M9, Canada.
Standish
Beau A
BA
Moriyama
Eduardo H
EH
Khurana
Mamta
M
Munce
Nigel R
NR
Leung
Michael K
MK
Jiang
James
J
Cable
Alex
A
Wilson
Brian C
BC
Vitkin
I Alex
IA
Yang
Victor X D
VX
D000465:Algorithms; D000818:Animals; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D051379:Mice; D008819:Mice, Nude; D008833:Microcirculation / Q000166:cytology*; D018613:Microscopy, Confocal / Q000379:methods*; D008856:Microscopy, Fluorescence / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D041623:Tomography, Optical Coherence / Q000379:methods*