Functional Near-Infrared Spectroscopy
Yu Chen, Babak Kateb in Neurophotonics and Brain Mapping, 2017
Diffuse optical imaging (DOI) is an emerging modality of medical imaging based on the use of near-infrared light. This technique permits to study living tissue noninvasively (Villringer and Chance 1997; Strangman et al. 2002). Its working principle capitalizes on the characteristic spectroscopic signatures of the molecules of interest. Its practical manifestation involves irradiating a narrow collimated beam over the biological tissue, where the light is scattered, and in response, part of it abandons the tissue to be collected by a detector. The sensed light encodes information about the physiological changes in the tissue in the form of changes in absorption and scattering. In the adult head, DOI becomes a practical form of functional neuroimaging known as functional near-infrared spectroscopy (fNIRS).
Optical Imaging
George C. Kagadis, Nancy L. Ford, Dimitrios N. Karnabatidis, George K. Loudos in Handbook of Small Animal Imaging, 2018
For additional, focused coverage of specific types of optical imaging, the interested reader is directed to the various excellent reviews covering diffuse optical imaging (Arridge and Hebden 1997; Arridge and Schweiger 1997; Hebden et al. 1997; Arridge 1999; Boas et al. 2001; Schweiger et al. 2003; Gibson et al. 2005; Arridge and Schotland 2009; Arridge 2011), fluorescence imaging (Weissleder and Ntziachristos 2003; Graves et al. 2004; Stuker et al. 2011; Darne et al. 2014), bioluminescence imaging (Wang et al. 2008a; Darne et al. 2014; Qin et al. 2014), Cerenkov imaging (Qin et al. 2012; Thorek et al. 2012; Das et al. 2014), and instrumentation (Ntziachristos et al. 2005; Zhang 2014).
Whole body measurements using near-infrared spectroscopy in a rat spinal cord contusion injury model
Published in The Journal of Spinal Cord Medicine, 2023
Brianna Kish, Seth Herr, Ho-Ching (Shawn) Yang, Siyuan Sun, Riyi Shi, Yunjie Tong
Near infrared spectroscopy (NIRS) is a diffuse optical imaging tool used for measuring the relative concentrations of oxyhemoglobin (Δ[HbO]) and deoxyhemoglobin (Δ[Hb]). Though blood flow is believed to be the predominant contributing factor in the NIRS signal, with increases of flow corresponding to an increase in Δ[HbO] and decrease in Δ[Hb], changes in blood volume and metabolic rate impact the signal as well, altogether reflecting complex hemodynamic changes. NIRS is a low cost, portable optical technology easily adaptable to record real-time physiologic changes from many locations over the body at once with high temporal resolution. While the system can act invasively, it also works noninvasively, allowing for examinations over long periods of time. Additionally, the system is easily set up and operated, making it ideal for quick and accurate measurements. Together, NIRS is a promising technique for assessing hemodynamic changes in SCI models.
Related Knowledge Centers
- Absorption
- Hemoglobin
- Optical Tomography
- Functional Near-Infrared Spectroscopy
- Scattering
- Near-Infrared Window In Biological Tissue
- Radiative Transfer Equation & Diffusion Theory For Photon Transport In Biological Tissue
- Time-Domain Diffuse Optics
- Computed Tomography Laser Mammography
- Diffuse Optical Mammography