Article

Bouchard MB, Chen BR, Burgess SA, Hillman EMCUltra-fast multispectral optical imaging of cortical oxygenation, blood flow, and intracellular calcium dynamics. Opt Express 17:15670-15678

Laboratory for Functional Optical Imaging, Departments of Biomedical Engineering and Radiology, Columbia University, New York, NY 10027, USA.
Optics Express (Impact Factor: 3.49). 09/2009; 17(18):15670-8. DOI: 10.1364/OE.17.015670
Source: PubMed

ABSTRACT

Camera-based optical imaging of the exposed brain allows cortical hemodynamic responses to stimulation to be examined. Typical multispectral imaging systems utilize a camera and illumination at several wavelengths, allowing discrimination between changes in oxy- and deoxyhemoglobin concentration. However, most multispectral imaging systems utilize white light sources and mechanical filter wheels to multiplex illumination wavelengths, which are slow and difficult to synchronize at high frame rates. We present a new LED-based system capable of high-resolution multispectral imaging at frame rates exceeding 220 Hz. This improved performance enables simultaneous visualization of hemoglobin oxygenation dynamics within single vessels, changes in vessel diameters, blood flow dynamics from the motion of erythrocytes, and dynamically changing fluorescence.

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Available from: Elizabeth M Hillman, Apr 06, 2014
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    • "IOS and laser Doppler flowmetry (LDF) data were collected using custom-written software in LabView 8.6 (National Instruments). For IOS imaging, four 530 nm LEDs (Thorlabs, M530L2-C1) (Bouchard et al., 2009) passed through a ± 10 nm filter (Thorlabs, FB530-10) were used to uniformly illuminate the cortical surface. A CCD camera (Dalsa, Pantera 1 M60) was used to acquire 12-bit images (Drew and Feldman, 2009). "
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    • "The keys to achieving this objective are the capability of quantifying the oxygen saturation level as well as blood flow speed and flux in individual vessels. By measuring the intensity of diffuse back-reflected light, multispectral imaging techniques such as optical intrinsic signal imaging (OISI) [4] have been applied to gauge oxygenation for decades but are unable to determine the path-length and hence cannot be used quantitatively. Recently, Wang et al. [5], demonstrated the ability to use reflection-mode photoacoustic microscopy to determine the oxygen delivery from single flowing red blood cells (RBCs) in vivo, based on assessing absorption via the photoacoustic effect. "
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    • "Moreover, Bouchard et al. proposed an LSCI system with a lower overall cost compared with the LSCI system currently employed in laboratory settings. This low-cost LSCI system enables simultaneous visualization of HbT, HbO2 and Hb dynamics within single vessels in response to forepaw stimulation [75]. LSCI has proven to be an important tool for neuroscience research, presenting excellent spatial and temporal resolutions and capabilities that extend beyond the visualization of cerebral functional and structural hemodynamic patterns. "
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