Dual-slope imaging of cerebral hemodynamics with frequency-domain near …

1. Introduction. Functional brain diffuse optical imaging (DOI) using near-infrared spectroscopy (NIRS) has seen an increase in its popularity and applications over the past 30 years. 1 – 3 During that time, functional near-infrared spectroscopy (fNIRS) has been demonstrated in both behavioural and social studies 2 and in clinical applications. 3 …

Time-domain near-infrared spectroscopy in acute ischemic …

Time-domain near-infrared spectroscopy (TD-NIRS) estimates the oxygenation of microcirculation of cerebral outer layers. We measure hemoglobin species and tissue oxygen saturation ( StO 2 ) of anterior circulation stroke patients, classified as LVO or lacunar, and assess the differences compared with controls and according to …

Frequency-Domain Techniques for Cerebral and Functional Near-Infrared

This article reviews the basic principles of frequency-domain near-infrared spectroscopy (FD-NIRS), which relies on intensity-modulated light sources and phase-sensitive optical detection, and its non-invasive applications to the brain. The simpler instrumentation and more straightforward data analysis of continuous-wave NIRS (CW-NIRS) accounts ...

Dynamic time domain near-infrared optical tomography based on …

In many clinical applications it is relevant to observe dynamic changes in oxygenation. Therefore the ability of dynamic imaging with time domain (TD) near-infrared optical tomography (NIROT) will be important. But fast imaging is a challenge. The data acquisition of our handheld TD NIROT system based on single photon avalanche diode …

Near Infrared Spectroscopy

Near-infrared (NIR) spectroscopy is the study of spectra recorded on instruments in the region 780–2500 nm. Many instruments add the visual region of 400–780 nm to this, so that colour information in the spectra can also be studied. Other instruments are more restrictive, e.g. between 850 and 1050 nm.

Monitoring muscle metabolic indexes by time-domain near-infrared …

A noninvasive methodology, combining functional electrical stimulation and time-domain near-infrared spectroscopy (TD-NIRS), is developed to verify whether stroke-altered muscular metabolism on postacute patients. Seven healthy subjects and nine postacute stroke patients undergo a protocol of knee flex-extension induced by quadricep electrical ...

Time-resolved near infrared light propagation using frequency domain

Abstract. Time-resolved temporal point spread function (TPSF) measurement of near infrared spectroscopic (NIRS) data allows the estimation of absorption and reduced scattering properties of biological tissues. Such analysis requires an iterative calculation of the theoretical TPSF curve using mathematical and computational models of the domain ...

How much do time-domain functional near-infrared …

Functional near-infrared spectroscopy (fNIRS) is a technology that measures functional changes in the hemodynamics of the brain. 1 In its simplest form, …

Single-domain near-infrared protein provides a scaffold for …

Small near-infrared (NIR) fluorescent proteins (FPs) are much needed as protein tags for imaging applications. We developed a 17 kDa NIR FP, called miRFP670nano3, which brightly fluoresces in ...

Single-domain near-infrared protein provides a scaffold for …

Optical imaging with near-infrared (NIR) fluorescent proteins (FPs) provides increased tissue penetration depths and a better signal-to-noise ratio due to reduced light-scattering, tissue absorption and autofluorescence in the NIR region (650–900 nm) 1, 2.NIR FPs allow labeling of whole organisms, specific cell populations, organelles or individual proteins, …

Frequency-domain vs continuous-wave near-infrared

Assessment of infant brain development with frequency-domain near-infrared spectroscopy. Pediatr Res. 2007;61:546–51. Article PubMed PubMed Central Google Scholar Wolf M, Ferrari M, Quaresima V. Progress of near-infrared spectroscopy and topography for brain and muscle clinical applications.

Sustained fatigue assessment during isometric exercises with …

The effect of sustained fatigue during an upper limb isometric exercise is presented to investigate a group of healthy subjects with simultaneous time-domain (TD) NIRS and surface electromyography (sEMG) recordings on the deltoid lateralis muscle. The ...

Single-distance and dual-slope frequency-domain near-infrared …

Near-infrared spectroscopy (NIRS) is a non-invasive optical technique that has been applied to measurements of the perfusion and oxygenation of various biological tissues, including skeletal muscle 1, 2 and brain. 3 NIRS studies have employed continuous-wave (CW), 4 – 7 time-domain (TD), 8 and frequency-domain (FD) 9, 10 …

Assessment of different spectral indices in the red-near-infrared …

A new spectral index named Burned Area Index (BAI), specifically designed for burned land discrimination in the red-near-infrared spectral domain, was tested on multitemporal sets of Landsat Thematic Mapper (TM) and NOAA Advanced Very High Resolution Radiometer (AVHRR) images. The utility of BAI for burned land discrimination …

A Novel Combined Frequency-Domain Near-Infrared …

Frequency domain near-infrared spectroscopy (FDNIRS) and diffuse correlation spectroscopy (DCS) use near-infrared light to quantify static and dynamic properties of brain tissue. We present a novel FDNIRS-DCS system and characterize its performance.

Early stage dental caries detection using near infrared …

The benefits of reduced scattering coefficient measurements using near infrared spatial frequency domain imaging are even more striking in the second case (Fig. (Fig.5e–h), 5 e–h), where scattering from an early-stage cavity (μ s ′ = 20 mm-1) is a factor of 40 greater than surrounding tissue (μ s ′ = 0.5 mm-1). Despite this difference ...

Time-domain near-infrared spectroscopy in acute ischemic stroke …

Time-domain near-infrared spectroscopy (TD-NIRS) estimates the oxygenation of microcirculation of cerebral outer layers. We measure hemoglobin species and tissue oxygen saturation (StO 2 ) of anterior circulation stroke patients, classified as LVO or lacunar, and assess the differences compared with controls and according to LVO …

A System for Fusing Color and Near-Infrared Images in Radiance Domain

Abstract: We designed and demonstrated a system that fused color and near-infrared (NIR) images in the radiance domain. The system is designed to enhance image quality captured in outdoor environments, especially in hazy weather conditions. Previous dehazing methods based on RGB-NIR fusion exist but have rarely addressed the issue of color …

Time-Domain Near-Infrared Spectroscopy and …

The time-domain (TD) technique in near-infrared spectroscopy (NIRS) and imaging technology has the greatest potential among the continuous wave (CW), frequency-domain (FD), and time-domain modalities owing to …

Shining a Light on Awareness: A Review of Functional Near …

In the near-infrared (NIR) range of light, with wavelengths between ~600 and 900 nm, biological tissues are effectively transparent. The low molar absorptivity of …

Time-Domain Near-Infrared Spectroscopy and Imaging: …

The time-domain (TD) technique in near-infrared spectroscopy (NIRS) and imaging technology has the greatest potential among the continuous wave (CW), frequency-domain (FD), and time-

High-sensitivity imaging of time-domain near-infrared light …

Near-infrared fluorescent probes can aid with optical imaging in the real-time visualization of passively stained tumours, blood vessels and nerves and can guide high-precision surgery 3, 4.

Design of a miniaturized frequency domain near infrared …

Frequency domain near infrared spectroscopy (fdNIR spectroscopy) is a technique that can be used to measure the absolute concentrations of HbO and HbR non-invasively and locally. The fdNIR spectrometer utilizes the attenuation and the phase shift (with respect to the source) ...

Functional Near-Infrared Spectroscopy (fNIRS) in Neuroergonomics …

Frequency-domain vs continuous-wave near-infrared spectroscopy devices: A comparison of clinically viable monitors in controlled hypoxia. Journal of Clinical Monitoring and Computing, 31(5), 967–974. Google Scholar de Winkel, K. N., Nesti, A., Ayaz, H., & Bülthoff, H. H. (2017). Neural correlates of decision making on whole body …

Time-domain near-infrared spectroscopy in acute ischemic stroke

Time-domain near-infrared spectroscopy (TD-NIRS) estimates the oxygenation of microcirculation of cerebral outer layers. We measure hemoglobin species and tissue oxygen saturation ( StO 2 ) of anterior circulation stroke patients, classified as LVO or lacunar, and assess the differences compared with controls and according to LVO …

Near Infrared Spectroscopy

Near Infrared Spectroscopy. eNear-infrared spectroscopy (NIRS) is a spectroscopic method that uses the near-infrared region of the electromagnetic spectrum (from 780 to 2500nm). ... Significant advances in NIRS technique include development of frequency-domain and time-domain (FD-NIRS and TD-NIRS) devices that allow quantification of …

NearWave imager: the first entirely handheld real-time frequency-domain

We demonstrate the first entirely handheld frequency-domain near-infrared spectroscopy imager capable of displaying 2D images in real-time. The system provides real-time imaging and addresses many of the limitations of prior fdNIRS systems including system size, speed, and ease of use.

Global Filter of Fusing Near-Infrared and Visible Images in …

Exploiting complementary advantages of different reflection and scattering properties of near-infrared (NIR) images and visible (VIS) images, this letter first proposes a defogging model for single image input and then develops an extended model, a fusion model for NIR and VIS color images, to enhance the visibility of image objects in scattering …

Single-domain near-infrared protein provides a scaffold for …

18 Citations. 43 Altmetric. Metrics. Abstract. Small near-infrared (NIR) fluorescent proteins (FPs) are much needed as protein tags for imaging applications. We …

Time-Domain Near-Infrared Spectroscopy and Imaging: …

The time-domain (TD) technique in near-infrared spectroscopy (NIRS) and imaging technology has the greatest potential among the continuous wave (CW), frequency …

Regional Cerebral Abnormalities Measured by Frequency-Domain Near …

This study assessed the feasibility of frequency-domain near-infrared spectroscopy (NIRS) for detection of intracranial complications during ECMO therapy. The frequency-domain NIRS device measured the absorption coefficient ( μ a ) and reduced scattering coefficient ( μ s ′) at six cranial positions from seven pediatric patients (0–16 ...

Design of a miniaturized frequency domain near infrared …

Frequency domain near infrared spectroscopy (fdNIR spectroscopy) is a technique that can be used to measure the absolute concentrations of HbO and HbR non-invasively and locally. The fdNIR spectrometer utilizes the attenuation and the phase shift (with respect to the source) that an intensity modulated NIR light experiences in order to ...

The visible and near-infrared domain | SpringerLink

Because the Earth's atmosphere transmits throughout most of the visible and infrared domain between 0.35 μm and 25 μm (generally referred to by astronomers as "optical and infrared" or OIR), astronomy flourished for millennia without access to space.Even in the space age, ground-based telescopes continue to provide us with OIR …

[PDF] Time-domain near-infrared spectroscopy in acute …

Time-domain near-infrared spectroscopy in acute ischemic stroke patients. TD-NIRS is able to detect significant differences in hemoglobin species in LVO stroke compared with controls and according to recanalization status, which might suggest that StO2 can serve as a surrogate functional marker of the metabolic activity of rescued …

How much do time-domain functional near-infrared …

Functional near-infrared spectroscopy (fNIRS) is a technology that measures functional changes in the hemodynamics of the brain. 1 In its simplest form, near-infrared sources and detectors are placed on the scalp, and changes in the optical properties of the tissue produced by hemodynamic activity are detected as changes in …

High-sensitivity imaging of time-domain near …

The optically transparent biological window in the near-infrared (NIR) spectral range allows deep-tissue excitation and the detection of fluorescence signals1,2. Spectrum-domain discrimination of ...

(PDF) Time-Domain Near-Infrared Spectroscopy and …

The time-domain (TD) technique in near-infrared spec troscopy (NIRS) and imaging technology . has the greatest potential among the continuous wave (CW), frequency-domain (FD), and time-