Ultra-fast multispectral optical imaging of cortical oxygenation, blood flow, and intracellular calcium dynamics. Opt Express

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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    NeuroImage 10/2014; 105. DOI:10.1016/j.neuroimage.2014.10.030 · 6.36 Impact Factor
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    • "as a response to the needs of real-time diagnosis of oral disease. Combined applications of biomedicine, spectroscopy, and illumination engineering have been undertaken in recent years to overcome these drawbacks [1] [2] [3] [4] [5] [6] [7]. The multi-spectral imaging (MSI) technique shows the most potential among these applications because of its real-time properties. "
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    • "Throughout these studies, correlations were found between the time courses of BOLD and optical data. These findings along with parallel studies in rodent models (Bouchard et al., 2009; Culver et al., 2003; Custo et al., 2009; Devor et al., 2003; Dunn et al., 2005; Siegel et al., 2003) and human neonates (Villringer and Chance, 1997) lay the foundation for optical measurements to be used in calculations of metabolic markers such as CMRO 2 at the bedside. Additionally, image-and time-domain comparisons have been made with simultaneously acquired MRI and NIRS (Toronov et al., 2007; Zhang et al., 2005). "
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