Towards the next generation of near-infrared spectroscopy

2011 ◽  
Vol 369 (1955) ◽  
pp. 4425-4439 ◽  
Author(s):  
Yoko Hoshi
Keyword(s):  
Infrared Spectroscopy ◽  
Data Analysis ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Optical Tomography ◽  
Quantitative Detection ◽  
Next Generation ◽  
Imaging Data ◽  
Wide Range ◽  
Detection Of Signals

Although near-infrared spectroscopy (NIRS) was originally designed for clinical monitoring of tissue oxygenation, it has also been developing into a useful tool for neuroimaging studies (functional NIRS). Over the past 30 years, technology has developed and NIRS has found a wide range of applications. However, the accuracy and reliability of NIRS have not yet been widely accepted, mainly because of the difficulties in selective and quantitative detection of signals arising in cerebral tissue, which subject the use of NIRS to a number of practical restrictions. This review summarizes the strengths and advantages of NIRS over other neuroimaging modalities and demonstrates specific examples. The issues of selective quantitative measurement of cerebral haemoglobin during brain activation are also discussed, together with the problems of applying the methods of functional magnetic resonance imaging data analysis to NIRS data analysis. Finally, near-infrared optical tomography—the next generation of NIRS—is described as a potential technique to overcome the limitations of NIRS.

scholarly journals Near-Infrared Spectroscopy for Monitoring Sternocleidomastoid Muscular Oxygenation during Isometric Flexion for Patients with Mild Nonspecific Neck Pain: A Pilot Study

Sensors ◽  
2020 ◽  
Vol 20 (8) ◽  
pp. 2197
Author(s):  
Chia-Chi Yang ◽  
Po-Ching Yang ◽  
Jia-Jin J. Chen ◽  
Yi-Horng Lai ◽  
Chia-Han Hu ◽  
...  
Keyword(s):  
Infrared Spectroscopy ◽  
Neck Pain ◽  
Near Infrared Spectroscopy ◽  
Isometric Contraction ◽  
Oxidative Metabolism ◽  
Near Infrared ◽  
Maximum Voluntary Isometric Contraction ◽  
Clinical Scenarios ◽  
Wide Range ◽  
Asymptomatic Individuals

Since there is merit in noninvasive monitoring of muscular oxidative metabolism for near-infrared spectroscopy in a wide range of clinical scenarios, the present study attempted to evaluate the clinical usability for featuring the modulatory strategies of sternocleidomastoid muscular oxygenation using near-infrared spectroscopy in mild nonspecific neck pain patients. The muscular oxygenation variables of the dominant or affected sternocleidomastoid muscles of interest were extracted at 25% of the maximum voluntary isometric contraction from ten patients (5 males and 5 females, 23.6 ± 4.2 years) and asymptomatic individuals (6 males and 4 females, 24.0 ± 5.1 years) using near-infrared spectroscopy. Only a shorter half-deoxygenation time of oxygen saturation during a sternocleidomastoid isometric contraction was noted in patients compared to asymptomatic individuals (10.43 ± 1.79 s vs. 13.82 ± 1.42 s, p < 0.001). Even though the lack of statically significant differences in most of the muscular oxygenation variables failed to refine the definite pathogenic mechanisms underlying nonspecific neck pain, the findings of modulatory strategies of faster deoxygenation implied that near-infrared spectroscopy appears to have practical potential to provide relevant physiological information regarding muscular oxidative metabolism and constituted convincing preliminary evidences of the adaptive manipulations rather than pathological responses of oxidative metabolism capacity of sternocleidomastoid muscles in nonspecific neck patients with mild disability.

scholarly journals Functional Near Infrared Spectroscopy (fNIRS) based Odor Detection and Classification using Functional Data Analysis

2021 ◽  
Author(s):  
Faezeh Moradi ◽  
Shima T. Moein ◽  
Issa Zakeri ◽  
Kambiz Pourrezaei
Keyword(s):  
Infrared Spectroscopy ◽  
Data Analysis ◽  
Near Infrared Spectroscopy ◽  
Functional Data Analysis ◽  
Functional Data ◽  
Near Infrared ◽  
Stimulus Condition ◽  
Functional Near Infrared Spectroscopy ◽  
Odor Detection ◽  
The Brain

AbstractAn objective approach for odor detection is to analyze the brain activity using imaging techniques during the odor stimulation. In this study, Functional Near Infrared Spectroscopy (fNIRS) is used to record hemodynamic response from the frontal region of the brain by using a 4-channel fNIRS system. The fNIRs data is collected during the odor detection task in which the subjects were asked to press a button when they detect the given odor. Functional Data Analysis (FDA) was applied on fNIRs data to convert discrete measured samples of data to continuous smooth curves. The FDA method enables us to use the bases coefficients of fNIRS smoothed curves for features that represent the shape of the raw fNIRS signal. With the learning algorithm that we proposed, these features were used to train the support vector machine classifier. We evaluated the odor detection problem, in two binary classification cases: odorant vs. non-odorant and odorant vs. fingertapping. The model achieved a classification accuracy of 94.12% and 97.06% over the stimulus condition in the two cases, respectively. Moreover to find the actual predictors we used the extracted defined features (slope, standard deviation, and delta) to train our classifier. We achieved an average accuracy of 91.18 % on classifying odorant vs. non-odorant and an accuracy of 94.12% for odorant vs. fingertapping on the stimulus condition. The results determined that fNIRs signals of odorant and non-odorant are distinguishable without being affected by the motor activity during the experiment.These findings suggest that fNIRs measurement on the forehead could be potentially used for objective and comparably inexpensive assessment of odor detection in cases that the subjective report is unreliable.

scholarly journals Near-Infrared Spectroscopy of the Surface of Mars Derived from TIGER Spectro-Imaging Data

1995 ◽  
Vol 149 ◽  
pp. 298-299
Author(s):  
P. Martin ◽  
P.C. Pinet ◽  
R. Bacon ◽  
A. Rousset
Keyword(s):  
Infrared Spectroscopy ◽  
Spatial Resolution ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Western Hemisphere ◽  
Imaging Data ◽  
Integral Field Spectrograph ◽  
Integral Field ◽  
Spectro Imaging

AbstractHigh spectral and spatial resolution telescopic observations of the western hemisphere of Mars, using the integral field spectrograph TIGER at 0.8-1.1 µm, are described.

scholarly journals Imaging System Based on Silicon Photomultipliers and Light Emitting Diodes for Functional Near-Infrared Spectroscopy

2020 ◽  
Vol 10 (3) ◽  
pp. 1068 ◽  
Author(s):  
Giovanni Maira ◽  
Antonio M. Chiarelli ◽  
Stefano Brafa ◽  
Sebania Libertino ◽  
Giorgio Fallica ◽  
...  
Keyword(s):  
Infrared Spectroscopy ◽  
Human Brain ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Light Emitting Diodes ◽  
Optical Tomography ◽  
System Optimization ◽  
Infrared Light ◽  
Functional Near Infrared Spectroscopy ◽  
Light Emitting

We built a fiber-less prototype of an optical system with 156 channels each one consisting of an optode made of a silicon photomultiplier (SiPM) and a pair of light emitting diodes (LEDs) operating at 700 nm and 830 nm. The system uses functional near-infrared spectroscopy (fNIRS) and diffuse optical tomography (DOT) imaging of the cortical activity of the human brain at frequencies above 1 Hz. In this paper, we discuss testing and system optimization performed through measurements on a multi-layered optical phantom with mechanically movable parts that simulate near-infrared light scattering inhomogeneities. The baseline optical characteristics of the phantom are carefully characterized and compared to those of human tissues. Here we discuss several technical aspects of the system development, such as LED light output drift and its possible compensation, SiPM linearity, corrections of channel signal differences, and signal-to-noise ratio (SNR). We implement an imaging algorithm that investigates large phantom regions. Thanks to the use of SiPMs, very large source-to-detector distances are acquired with a high SNR and 2 Hz time resolution. The overall results demonstrate the high potentialities of a system based on SiPMs for fNIRS/DOT human brain imaging applications.

Accuracy of a Cerebral Oximeter in Healthy Volunteers under Conditions of Isocapnic Hypoxia 

1998 ◽  
Vol 88 (1) ◽  
pp. 58-65 ◽  
Author(s):  
Lindsey C. Henson ◽  
Carolyn Calalang ◽  
John A. Temp ◽  
Denham S. Ward
Keyword(s):  
Infrared Spectroscopy ◽  
Oxygen Saturation ◽  
Healthy Volunteers ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Cerebral Oxygenation ◽  
Jugular Bulb ◽  
Wide Range ◽  
Cerebral Oximeter ◽  
End Tidal

Background A cerebral oximeter measures oxygen saturation of brain tissue noninvasively by near infrared spectroscopy. The accuracy of a commercially available oximeter was tested in healthy volunteers by precisely controlling end-tidal oxygen (P[ET]O2) and carbon dioxide (P[ET]CO2) tensions to alter global cerebral oxygen saturation. Methods In 30 healthy volunteers, dynamic end-tidal forcing was used to produce step changes in P[ET]O2 resulting in arterial saturation ranging from approximately 70% to 100% under conditions of controlled normocapnia (each person's resting P[ET]CO2) or hypercapnia (resting plus 7-10 mmHg). Blood arterial (SaO2) and jugular bulb venous (S[jv]O2) saturations during each P(ET)O2 interval were determined by co-oximetry. The cerebral oximeter reading (rSO2) and an estimated jugular venous saturation (S[jv]O2), derived from a combination of SaO2 and rSO2, were compared with the measured S(jv)O2. Results The S(jv)O2 was significantly higher with hypercapnia than with normocapnia for the same SaO2. The rSO2 and S(jv)O2 were both highly correlated with S(jv)O2 for individual volunteers (mean r2 = 0.91 for each relation); however, the slopes and intercepts varied widely among volunteers. In three of them, the cerebral oximeter substantially underestimated the measured S(jv)O2. Conclusions During isocapnic hypoxia in healthy persons, cerebral oxygenation as estimated by near infrared spectroscopy precisely tracks changes in measured S(jv)O2 within individuals, but the relation exhibits a wide range of slopes and intercepts. Therefore the clinical utility of the device is limited to situations in which tracking trends in cerebral oxygenation would be acceptable.

scholarly journals Application of Near-Infrared Spectroscopy to Quantitatively Determine Relative Content of Puccnia striiformis f. sp. tritici DNA in Wheat Leaves in Incubation Period

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Yaqiong Zhao ◽  
Yilin Gu ◽  
Feng Qin ◽  
Xiaolong Li ◽  
Zhanhong Ma ◽  
...  
Keyword(s):  
Infrared Spectroscopy ◽  
Incubation Period ◽  
Stripe Rust ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Puccinia Striiformis ◽  
Quantitative Detection ◽  
Support Vector ◽  
Infected Leaf ◽  
Wheat Leaves

Stripe rust caused by Puccinia striiformis f. sp. tritici (Pst) is a devastating wheat disease worldwide. Potential application of near-infrared spectroscopy (NIRS) in detection of pathogen amounts in latently Pst-infected wheat leaves was investigated for disease prediction and control. A total of 300 near-infrared spectra were acquired from the Pst-infected leaf samples in an incubation period, and relative contents of Pst DNA in the samples were obtained using duplex TaqMan real-time PCR arrays. Determination models of the relative contents of Pst DNA in the samples were built using quantitative partial least squares (QPLS), support vector regression (SVR), and a method integrated with QPLS and SVR. The results showed that the kQPLS-SVR model built with a ratio of training set to testing set equal to 3 : 1 based on the original spectra, when the number of the randomly selected wavelength points was 700, the number of principal components was 8, and the number of the built QPLS models was 5, was the best. The results indicated that quantitative detection of Pst DNA in leaves in the incubation period could be implemented using NIRS. A novel method for determination of latent infection levels of Pst and early detection of stripe rust was provided.

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