Spectroscopic technique with wide range of wavelength information improves near-infrared spectroscopy

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.

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

Anesthesiology ◽

10.1097/00000542-199801000-00011 ◽

1998 ◽

Vol 88 (1) ◽

pp. 58-65 ◽

Cited By ~ 78

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.

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A method for assessing heterogeneity of blood flow and metabolism in exercising normal human muscle by near-infrared spectroscopy

Journal of Applied Physiology ◽

10.1152/japplphysiol.00458.2014 ◽

2015 ◽

Vol 118 (6) ◽

pp. 783-793 ◽

Cited By ~ 39

Author(s):

Ioannis Vogiatzis ◽

Helmut Habazettl ◽

Zafeiris Louvaris ◽

Vasileios Andrianopoulos ◽

Harrieth Wagner ◽

...

Keyword(s):

Blood Flow ◽

Infrared Spectroscopy ◽

Near Infrared Spectroscopy ◽

Near Infrared ◽

Vastus Lateralis ◽

Regional Distribution ◽

Human Muscle ◽

Relative Dispersion ◽

Wide Range ◽

Normal Human

Heterogeneity in the distribution of both blood flow (Q̇) and O2 consumption (V̇o2) has not been assessed by near-infrared spectroscopy in exercising normal human muscle. We used near-infrared spectroscopy to measure the regional distribution of Q̇ and V̇o2 in six trained cyclists at rest and during constant-load exercise (unloaded pedaling, 20%, 50%, and 80% of peak Watts) in both normoxia and hypoxia (inspired O2 fraction = 0.12). Over six optodes over the upper, middle, and lower vastus lateralis, we recorded 1) indocyanine green dye inflow after intravenous injection to measure Q̇; and 2) fractional tissue O2 saturation (StiO2) to estimate local V̇o2-to-Q̇ ratios (V̇o2/Q̇). Varying both exercise intensity and inspired O2 fraction provided a (directly measured) femoral venous O2 saturation range from about 10 to 70%, and a correspondingly wide range in StiO2. Mean Q̇-weighted StiO2 over the six optodes related linearly to femoral venous O2 saturation in each subject. We used this relationship to compute local muscle venous blood O2 saturation from StiO2 recorded at each optode, from which local V̇o2/Q̇ could be calculated by the Fick principle. Multiplying regional V̇o2/Q̇ by Q̇ yielded the corresponding local V̇o2. While six optodes along only in one muscle may not fully capture the extent of heterogeneity, relative dispersion of both Q̇ and V̇o2 was ∼0.4 under all conditions, while that for V̇o2/Q̇ was minimal (only ∼0.1), indicating in fit young subjects 1) a strong capacity to regulate Q̇ according to regional metabolic need; and 2) a likely minimal impact of heterogeneity on muscle O2 availability.

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Noninvasive determination of hemoglobin saturation in dogs by derivative near-infrared spectroscopy

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1989.256.5.h1493 ◽

1989 ◽

Vol 256 (5) ◽

pp. H1493-H1499 ◽

Cited By ~ 2

Author(s):

M. Ferrari ◽

D. A. Wilson ◽

D. F. Hanley ◽

J. F. Hartmann ◽

M. C. Rogers ◽

...

Keyword(s):

Infrared Spectroscopy ◽

Near Infrared Spectroscopy ◽

Near Infrared ◽

Linear Regression Analysis ◽

Sagittal Sinus ◽

Hemoglobin Saturation ◽

Wide Range ◽

Anesthetized Dogs ◽

Predicted Values

An in vivo method utilizing derivative near-infrared spectroscopy was developed to noninvasively determine cerebral venous hemoglobin O2 saturation (SVO2). The method was tested on eight pentobarbital-anesthetized dogs ventilated with differing inspired O2 mixtures to force changes in SVO2 over a wide range. Spectral data obtained by transilluminating the tissues surrounding the superior sagittal sinus (SS) were transformed into first derivative units for correlation with SVO2 data measured from the SS. Linear regression analysis was applied to data obtained from five dogs and used to build a three-wavelength algorithm for predicting brain SVO2. In three dogs, SVO2 was varied to test this equation ability to predict SVO2. The standard deviation of differences between measured SVO2 and SVO2 predicted from 31 separate spectra was 3.2%. These predicted values, when regressed against the sampled SVO2, yielded an r value of 0.97. The results demonstrate that during hypoxic hypoxia (HH) it is possible to noninvasively quantify SVO2 with the use of infrared spectroscopy.

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Near infrared spectroscopy for world food security

NIR news ◽

10.1177/0960336019875657 ◽

2019 ◽

Vol 30 (7-8) ◽

pp. 19-22

Author(s):

Graeme D Batten

Keyword(s):

Infrared Spectroscopy ◽

Food Security ◽

Near Infrared Spectroscopy ◽

Management Practices ◽

Near Infrared ◽

Crop Yields ◽

Food And Agriculture ◽

First Choice ◽

Wide Range ◽

World Food Security

The Food and Agriculture Organization predicts that 70% more food will be required to ensure food security by the year 2050 and that cereal production must increase from 2.1 to 3 billion tonnes per year. Timely, reliable and inexpensive data will be vital for farm managers to be able to maximise crop yields. Near infrared spectroscopy is now the analytical technology of first choice to obtain these data. Quantitative near infrared spectroscopy requires calibrations to be developed using reference data from traditional methods. Today these calibrations are available for a wide range of constituents in soils, plants and products and in turn they can be related to the yield and quality of food produced. Calibrations continue to be reported for a wider range of food stuffs and their constituents and we see near infrared being adopted both on-farm and in-factory across a variety of food sectors. To make a tangible contribution to food security, the data generated from these calibrations must facilitate crop management practices which maintain or promote yield. In this article, I present examples from my own experience to illustrate why it is important to understand the basis of a model developed from near infrared spectra and why errors due to sampling and poor reference values can negate the benefits from using near infrared spectroscopy.

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Multi-Way Analysis Coupled with Near-Infrared Spectroscopy in Food Industry: Models and Applications

Foods ◽

10.3390/foods10040802 ◽

2021 ◽

Vol 10 (4) ◽

pp. 802

Author(s):

Huiwen Yu ◽

Lili Guo ◽

Mourad Kharbach ◽

Wenjie Han

Keyword(s):

Infrared Spectroscopy ◽

Near Infrared Spectroscopy ◽

Food Systems ◽

Food Industry ◽

Near Infrared ◽

Full Potential ◽

Wide Range ◽

Powerful Analytical Tool ◽

Nirs Data ◽

Classification Prediction

Near-infrared spectroscopy (NIRS) is a fast and powerful analytical tool in the food industry. As an advanced chemometrics tool, a multi-way analysis shows great potential for solving a wide range of food problems and analyzing complex spectroscopic data. This paper describes the representative multi-way models which were used for analyzing NIRS data, as well as the advances, advantages and limitations of different multi-way models. The applications of a multi-way analysis in NIRS for the food industry in terms of food process control, quality evaluation and fraud, identification and classification, prediction and quantification, and image analysis are also reviewed. It is evident from this report that a multi-way analysis is presently an attractive tool for modeling complex NIRS data in the food industry while its full potential is far from reached. The combination of a multi-way analysis with NIRS will be a promising practice for turning food data information into operational knowledge, conducting reliable food analyses and improving our understanding about food systems and food processes. To the best of our knowledge, this is the first paper that systematically reports the advances on models and applications of a multi-way analysis in NIRS for the food industry.

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Remote sensing of exoplanetary atmospheres with ground-based high-resolution near-infrared spectroscopy

Astronomy and Astrophysics ◽

10.1051/0004-6361/201935691 ◽

2019 ◽

Vol 629 ◽

pp. A109 ◽

Cited By ~ 2

Author(s):

D. Shulyak ◽

M. Rengel ◽

A. Reiners ◽

U. Seemann ◽

F. Yan

Keyword(s):

Infrared Spectroscopy ◽

Temperature Distribution ◽

High Resolution ◽

Near Infrared Spectroscopy ◽

Atmospheric Chemistry ◽

Near Infrared ◽

Optimal Estimation ◽

High Resolution Spectroscopy ◽

High Signal ◽

Wide Range

Context. Thanks to the advances in modern instrumentation we have learned about many exoplanets that span a wide range of masses and composition. Studying their atmospheres provides insight into planetary origin, evolution, dynamics, and habitability. Present and future observing facilities will address these important topics in great detail by using more precise observations, high-resolution spectroscopy, and improved analysis methods. Aims. We investigate the feasibility of retrieving the vertical temperature distribution and molecular number densities from expected exoplanet spectra in the near-infrared. We use the test case of the CRIRES+ instrument at the Very Large Telescope which will operate in the near-infrared between 1 and 5 μm and resolving powers of R = 100 000 and R = 50 000. We also determine the optimal wavelength coverage and observational strategies for increasing accuracy in the retrievals. Methods. We used the optimal estimation approach to retrieve the atmospheric parameters from the simulated emission observations of the hot Jupiter HD 189733b. The radiative transfer forward model is calculated using a public version of the τ-REx software package. Results. Our simulations show that we can retrieve accurate temperature distribution in a very wide range of atmospheric pressures between 1 bar and 10−6 bar depending on the chosen spectral region. Retrieving molecular mixing ratios is very challenging, but a simultaneous observations in two separate infrared regions around 1.6 and 2.3 μm helps to obtain accurate estimates; the exoplanetary spectra must be of relatively high signal-to-noise ratio S∕N ≥ 10, while the temperature can already be derived accurately with the lowest value that we considered in this study (S∕N = 5). Conclusions. The results of our study suggest that high-resolution near-infrared spectroscopy is a powerful tool for studying exoplanet atmospheres because numerous lines of different molecules can be analyzed simultaneously. Instruments similar to CRIRES+ will provide data for detailed retrieval and will provide new important constraints on the atmospheric chemistry and physics.

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Towards the next generation of near-infrared spectroscopy

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2011.0262 ◽

2011 ◽

Vol 369 (1955) ◽

pp. 4425-4439 ◽

Cited By ~ 43

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.

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