Near-infrared Spectroscopy Device Research Articles

Impact of breast milk on cortical pain response in newborns during the heel prick procedure: a randomized controlled trial.

To investigate the effects of breast milk on cortical pain response and behavioral response in newborns during heel-prick procedure. A prospective, randomized controlled trial was conducted on healty-term newborns, undergoing heel blood sampling. Infants were randomly assigned to study group with receive orally 2 ml breast milk (n = 45) or a control group with no intervention (n = 45). A near-infrared spectroscopy device was used to monitor regional cerebral oxygen saturation (rScO2), while neonatal pain expression was assessed by Neonatal Pain, Agitation, and Sedation Scale (N-PASS). The N-PASS score (p = 0.001) and the crying time (p = 0.017) were significantly lower in the study group compared to the control group. Although the mean rScO2 values decreased in both groups during the procedure, the percent change in rScO2 was not significant difference between two groups. Breast milk administration decreases behavioral responses to a noxious stimulus without reducing the cortical response to pain. This trial was registered under ClinicalTrials.gov identifier no. NCT05961904.

Handheld Near-Infrared Spectroscopy for Undried Forage Quality Estimation.

This study investigates the efficacy of handheld Near-Infrared Spectroscopy (NIRS) devices for in-field estimation of forage quality using undried samples. The objective is to assess the precision and accuracy of multiple handheld NIRS instruments-NeoSpectra, TrinamiX, and AgroCares-when evaluating key forage quality metrics such as Crude Protein (CP), Neutral Detergent Fiber (aNDF), Acid Detergent Fiber (ADF), Acid Detergent Lignin (ADL), in vitro Total Digestibility (IVTD)and Neutral Detergent Fiber Digestibility (NDFD). Samples were collected from silage bunkers across 111 farms in New York State and scanned using different methods (static, moving, and turntable). The results demonstrate that dynamic scanning patterns (moving and turntable) enhance the predictive accuracy of the models compared to static scans. Fiber constituents (ADF, aNDF) and Crude Protein (CP) show higher robustness and minimal impact from water interference, maintaining similar R2 values as dried samples. Conversely, IVTD, NDFD, and ADL are adversely affected by water content, resulting in lower R2 values. This study underscores the importance of understanding the water effects on undried forage, as water's high absorption bands at 1400 and 1900 nm introduce significant spectral interference. Further investigation into the PLSR loading factors is necessary to mitigate these effects. The findings suggest that, while handheld NIRS devices hold promise for rapid, on-site forage quality assessment, careful consideration of scanning methodology is crucial for accurate prediction models. This research contributes valuable insights for optimizing the use of portable NIRS technology in forage analysis, enhancing feed utilization efficiency, and supporting sustainable dairy farming practices.

NIRO200NX: Reliable Monitoring System for Buried Deep Inferior Epigastric Perforator Flap.

The deep inferior epigastric perforator (DIEP) flap is a useful tool for breast reconstruction and tends to be transferred into the breast envelope as the buried flap from an aesthetic point of view. However, it is difficult to monitor the blood flow in the buried DIEP flap after reconstructive microsurgery. Near-infrared spectroscopy devices have recently been used for monitoring the blood flow of various organs. NIRO200NX (Hamamatsu Photonics) continuously measures the tissue oxygen index (TOI) and quickly reflects changes in flap blood flow. In this study, we investigated whether and how much the NIRO200NX applies to monitoring the blood flow of the buried flap. We included 156 patients who underwent breast reconstruction using a DIEP flap from October 2013 to May 2022, comprising 57 exposed and 99 buried-type DIEP flap cases. We measured TOI using NIRO200NX, in combination with conventional evaluation methods, including color check, pinprick test, and Doppler sound. A criterion of TOI 50 gave the best evaluations. All the 57 exposed-type flap cases showed no false evaluations, and NIRO200NX performed precise judgment. In 99 buried-type flap cases, NIRO200NX correctly evaluated 96 cases. For those buried-type cases, we found only two false-positive and one false-negative case. The misjudgments by NIRO200NX were likely caused by hematoma. We propose NIRO200NX as a reliable device for monitoring the blood flow of the DIEP flap and predicting the outcomes of breast reconstruction by the DIEP flap transfer.

The Role of Cerebral Oximetry in Predicting and Preventing Postoperative Cognitive Dysfunction

Postoperative Cognitive Dysfunction (POCD) is a serious problem that is frequently seen especially in elderly patients and can cause permanent cognitive decline, prolonged hospital stay, loss of independence, decreased quality of life and even mortality. Identifying individuals at risk of developing POCD can prevent this condition by enabling the development of early interventions. POCD has a multifactorial etiology, and intraoperative cerebral perfusion disorder is considered to be one of these mechanisms. Near-infrared Spectroscopy (NIRS) device provides monitoring of regional brain oxygenation. There are studies on the predictability and preventability of cognitive disorders that may develop after surgery with the use of NIRS. In this article, it is aimed to present the study results and inferences regarding the relationships between the areas of use of NIRS and the pathogenesis of POCD.

Rapid determination of chicken meat ratios in Beef Mixtures and Beef Sausages by Near Infrared Reflectance (NIR) spectroscopy

This study aims to determine the percentage of chicken meat in beef and chicken mixtures, which is the most common form of beef adulteration. Ground beef and beef sausages were prepared with mixtures containing chicken meat, ranging from 0.0% to 100.0% with 5.0% increments, and analyzed using a near-infrared spectroscopy device. Optimal analysis conditions were determined through the examination of a wide range of regression models. The best regression model for ground beef mixtures yielded the following results: RMSEC (Root Mean Square Error of Calibration): 2.35, RMSEV (Root Mean Square Error of Validation): 3.36, R2C (R-Value Calibration): 0.99, R2V (R-Value Validation): 0.98. The results for beef sausages were as follows: RMSEC: 2.56, RMSEV: 3.66, R2C: 0.99, R2V: 0.98. As a result, the chicken meat content in beef mixtures was detected with a margin of error of 2.05%, while the chicken meat content in beef sausages was detected with a margin of error of 2.12%.

Non-destructive authentication of melon seed (Cucumeropsis mannii) powder using a pocket-sized near-infrared (NIR) spectrophotometer with multiple spectral preprocessing

Increasing demand for plant-based proteins has elicited suspicions of fraudulent practices among some producers of melon seed powder. The powder is suspected to be adulterated with carbohydrate-rich foods including maize, dried-milled cassava (gari) and soy flour to boost its quantity for increased profit. This study aimed to develop robust models using near-infrared spectroscopy (NIRS) for rapid authentication of melon seed powder. Melon seed powder samples containing 0–50 %w/w maize, gari and soy were prepared in triplicates and scanned using a handheld NIRS device. Proximate composition and color were significantly (p<0.05) affected by adulterant presence in melon seed powder. Classification models using linear discriminant analysis yielded accuracies of adulterant classification that were further confirmed by the high sensitivity, specificity and precision of the models (higher than 80 % in all cases). Low errors (RMSEC 3.28, RMSECV 3.92, RMSEP 6.87) % w/w, limits of detection and quantification and high coefficients (R2 0.96, R2CV 0.94, R2PRED 0.81) % w/w, indicative of reliable partial least squares models were obtained for the prediction of adulterants, protein, carbohydrate, total colour change, fat and lightness. Overall, Savitisky-Golay smoothing filter yield the best results in all LDA analysis. NIRS is a viable option for rapid non-invasive authentication of melon seed powder. The handheld device presents an added advantage of remote analysis. Instruments with other wavelength ranges can be explored in a similar approach study but with a higher sample size for more rigorous applications.

The Effect of Graded Running Protocols On Peak Oxygen Consumption and Intramuscular Oxygen Saturation

Aim: The aim of this investigation was to examine the impact of two different running protocols on peak oxygen consumption (VO2max) and regional intramuscular oxygen saturation (SmO2) levels in one highly trained runner. Methods: VO2 and SmO2 were measured simultaneously during a gradually ascending running protocol and a Bruce protocol. VO2 was measured by breath-by-breath spiroergometer gas analysis system (ZAN®, Germany), and SmO2 was measured from both gastrocnemius muscles using a wireless near-infrared spectroscopy device (BSXinsight®, USA). The correlation between VO2 and SmO2 data was determined by Pearson correlation coefficients over the test stage mean values. The change of VO2 and SmO2 within each stage was determined by first-degree polynomials. Results: Peak VO2 in the Bruce protocol (4390 ml/min) was higher than peak VO2 in the running protocol (4640 ml/min), but no difference was observed in end-test SmO2 decreases. There were highly significant negative correlations between VO2 values and SmO2 values (r=-0.960-0.990, p

Side differences and reproducibility of the Moxy muscle oximeter during cycling in trained men.

Portable near-infrared spectroscopy devices allow measurements of muscle oxygen saturation (SmO2) in real time and non-invasively. To use NIRS for typical applications including intensity control and load monitoring, the day-to-day variability needs to be known to interpret changes confidently. This study investigates the absolute and relative test-retest reliability of the Moxy Monitor and investigates side differences of SmO2 at the vastus lateralis muscle of both legs in cyclists. Twelve trained cyclists and triathletes completed 3 incremental step tests with 5min step duration starting at 1.0W/kg with an increase of 0.5W/kg separated by 2-7days. SmO2 was averaged over the last minute of each stage. For all power outputs, the intra-class coefficient (ICC), the standard error of measurement (SEM) and the minimal detectable change (MDC) were calculated. Dominant and non-dominant leg SmO2 were compared using a three-factor ANOVA and limits of agreement (LoA). ANOVA showed no significant systematic differences between trials and side. For both legs and all intensities, the ICC ranged from 0.79 to 0.92, the SEM from 5 to 9% SmO2 and the MDC from 14 to 18% SmO2. The bias and LoA between both legs were -2.0% ± 19.9% SmO2. Relative reliability of SmO2 was numerically good to excellent according to current standards. However, it depends on the specific analytical goal whether the test-retest reliability is deemed sufficient. Wide LoA indicate side differences in muscle oxygenation during exercise unexplained by leg dominance.

Sourcebook update: using near-infrared spectroscopy to assess skeletal muscle oxygen uptake.

Monitoring the metabolic cost or oxygen consumption associated with rest and exercise is crucial to understanding the impact of disease or physical training on the health of individuals. Traditionally, measuring the skeletal muscle oxygen cost associated with exercise/muscle contractions can be rather expensive or invasive (i.e., muscle biopsies). More recently, specific protocols designed around the use of near-infrared spectroscopy (NIRS) have been shown to provide a quick, noninvasive easy-to-use tool to measure skeletal muscle oxygen consumption ([Formula: see text]). However, the data and results from NIRS devices are often misunderstood. Thus the primary purpose of this sourcebook update is to provide several experimental protocols students can utilize to improve their understanding of NIRS technology, learn how to analyze results from NIRS devices, and better understand how muscle contraction intensity and type (isometric, concentric, or eccentric) influence the oxygen cost of muscle contractions.NEW & NOTEWORTHY Compared to traditional methods, near-infrared spectroscopy (NIRS) provides a relatively cheap and easy-to-use noninvasive technique to measure skeletal muscle oxygen uptake following exercise. This laboratory not only enables students to learn about the basics of NIRS and muscle energetics but also addresses more complex questions regarding skeletal muscle physiology.

Bagging Algorithm Based on Possibilistic Data Interpolation for Brain-Computer Interface

Recently, brain-computer interfaces (BCIs) and brain-machine interfaces have garnered the attention of researchers. Based on connections with external devices, external computers and machines can be controlled by brain signals measured via near-infrared spectroscopy (NIRS) or electroencephalograph devices. Herein, we propose a novel bagging algorithm that generates interpolation data around misclassified data using a possibilistic function, to be applied to BCIs. In contrast to AdaBoost, which is a conventional ensemble learning method that increases the weight of misclassified data to incorporate them with high probability to the next datasets, we generate interpolation data using a membership function centered on misclassified data and incorporate them into the next datasets simultaneously. The interpolated data are known as virtual data herein. By adding the virtual data to the training data, the volume of the training data becomes sufficient for adjusting the discriminate boundary more accurately. Because the membership function is defined as a possibility distribution, this method is named the bagging algorithm based on the possibility distribution. Herein, we formulate a bagging-type ensemble learning based on the possibility distribution and discuss the usefulness of the proposed method for solving simple calculations using NIRS data.

Differentiation between fresh and frozen-thawed mackerel fish using low-cost portable near infrared spectrometry devices

Mislabelling frozen-thawed fish fillets as fresh is one of the most important fraudulent practices during commercialisation. This study aimed to determine the ability of two portable miniaturised low-cost near-infrared spectroscopy (NIR) devices intended for consumers to discriminate between fresh and thawed mackerel (submitted to one or two frozen-thawed cycles) and between different freezing systems. The effect of different fish seasonal characteristics on the performance of the model was also evaluated. The low-cost NIR devices were able to discriminate between fresh and thawed samples with a classification rate of 90.3% and 94.1% and the freezing system to which they were submitted with a classification rate of 91.2% and 89.7%. These findings suggest that low-cost portable NIR spectroscopy can be a valuable tool for detecting mislabeled frozen-thawed products sold as fresh, providing consumers with a rapid and affordable method for fraud detection.

Assessing changes in regional cerebral hemodynamics in adults with a high-density full-head coverage time-resolved near-infrared spectroscopy device.

Cerebral oximeters have the potential to detect abnormal cerebral blood oxygenation to allow for early intervention. However, current commercial systems have two major limitations: (1)spatial coverage of only the frontal region, assuming that surgery-related hemodynamic effects are global and (2)susceptibility to extracerebral signal contamination inherent to continuous-wave near-infrared spectroscopy (NIRS). This work aimed to assess the feasibility of a high-density, time-resolved (tr) NIRS device (Kernel Flow) to monitor regional oxygenation changes across the cerebral cortex during surgery. The Flow system was assessed using two protocols. First, digital carotid compression was applied to healthy volunteers to cause a rapid oxygenation decrease across the ipsilateral hemisphere without affecting the contralateral side. Next, the system was used on patients undergoing shoulder surgery to provide continuous monitoring of cerebral oxygenation. In both protocols, the improved depth sensitivity of trNIRS was investigated by applying moment analysis. A dynamic wavelet filtering approach was also developed to remove observed temperature-induced signal drifts. In the first protocol ( years; five females, five males), hair significantly impacted regional sensitivity; however, the enhanced depth sensitivity of trNIRS was able to separate brain and scalp responses in the frontal region. Regional sensitivity was improved in the clinical study given the age-related reduction in hair density of the patients ( years; 14 females, 13 males). In five patients who received phenylephrine to treat hypotension, different scalp and brain oxygenation responses were apparent, although no regional differences were observed. The Kernel Flow has promise as an intraoperative neuromonitoring device. Although regional sensitivity was affected by hair color and density, enhanced depth sensitivity of trNIRS was able to resolve differences in scalp and brain oxygenation responses in both protocols.

Snapshot Near-Infrared Spectroscopy Device

Snapshot Near-Infrared Spectroscopy Device

Reproducibility and sex differences in muscle oxygenation during brachial artery occlusion in healthy participants.

Near-infrared spectroscopy (NIRS) measurement is a widely used technique to measure muscle oxygenation. A knowledge of the reproducibility of NIRS measurements is essential for the correct interpretation of data. Our aim was to test the reproducibility and sex differences of NIRS measurements during brachial artery occlusion in healthy participants. An NIRS device was used to measure muscle oxygenation and microvascular function during a 5 min brachial occlusion. Muscle oxygen consumption (mVO2) and tissue saturation index (TSI%) were used. The occlusion test was performed three times on separate days for males (n = 13, 28 ± 8 years) and females (n = 13, 29 ± 7 years). During the occlusion phase, the reproducibility of mVO2 was excellent (intraclass correlation; ICC = 0.90). During the reperfusion phase, the maximal change in TSI% revealed the best reproducibility (ICC = 0.77). There were no sex differences in reproducibility. Male participants had higher muscle oxygenation during occlusion (mVO2, 0.054 ± 0.010 vs. 0.038 ± 0.012 mLO2/min/100 g, p = 0.001, male and female, respectively). There were no sex differences during the reperfusion phase. The reproducibility of NIRS to measure muscle oxygenation and microvascular function during circulation occlusion and reperfusion is good to excellent. Muscle oxygen capacity measured during occlusion is higher in males compared to females, and there are no sex differences in microvascular function during the reperfusion phase.

Construction and evaluation of a neurofeedback system using finger tapping and near-infrared spectroscopy.

Neurofeedback using near-infrared spectroscopy (NIRS) has been used in patients with stroke and other patients, but few studies have included older people or patients with cognitive impairment. We constructed a NIRS-based neurofeedback system and used finger tapping to investigate whether neurofeedback can be implemented in older adults while finger tapping and whether brain activity improves in older adults and healthy participants. Our simple neurofeedback system was constructed using a portable wearable optical topography (WOT-HS) device. Brain activity was evaluated in 10 older and 31 healthy young individuals by measuring oxygenated hemoglobin concentration during finger tapping and neurofeedback implementation. During neurofeedback, the concentration of oxygenated hemoglobin increased in the prefrontal regions in both the young and older participants. The results of this study demonstrate the usefulness of neurofeedback using simple NIRS devices for older adults and its potential to mitigate cognitive decline.

Application of the Single Source-Detector Separation Algorithm in Wearable Neuroimaging Devices: A Step toward Miniaturized Biosensor for Hypoxia Detection.

Most currently available wearable devices to noninvasively detect hypoxia use the spatially resolved spectroscopy (SRS) method to calculate cerebral tissue oxygen saturation (StO2). This study applies the single source-detector separation (SSDS) algorithm to calculate StO2. Near-infrared spectroscopy (NIRS) data were collected from 26 healthy adult volunteers during a breath-holding task using a wearable NIRS device, which included two source-detector separations (SDSs). These data were used to derive oxyhemoglobin (HbO) change and StO2. In the group analysis, both HbO change and StO2 exhibited significant change during a breath-holding task. Specifically, they initially decreased to minimums at around 10 s and then steadily increased to maximums, which were significantly greater than baseline levels, at 25-30 s (p-HbO < 0.001 and p-StO2 < 0.05). However, at an individual level, the SRS method failed to detect changes in cerebral StO2 in response to a short breath-holding task. Furthermore, the SSDS algorithm is more robust than the SRS method in quantifying change in cerebral StO2 in response to a breath-holding task. In conclusion, these findings have demonstrated the potential use of the SSDS algorithm in developing a miniaturized wearable biosensor to monitor cerebral StO2 and detect cerebral hypoxia.

Near-Infrared Spectroscopy Does Not Track Forearm Blood Flow during Venous Occlusion Plethysmography

Background: Venous occlusion plethysmography (VOP) non-invasively measures forearm blood flow (FBF), whereas near-infrared spectroscopy (NIRS) assesses skeletal muscle oxygenation. Using these techniques has revealed sex differences in microvascular responses. However, it is not clear if NIRS and VOP results are interchangeable under various conditions like reactive hyperemia (RH). Our purpose was to evaluate sex-specific associations between FBF and NIRS-derived parameters: oxygenated hemoglobin, deoxygenated hemoglobin, total hemoglobin, and hemoglobin difference (O2Hb, HHb, tHb, and HbDiff). Methods: In total, 29 adults (15 men) participated, and a strain-gauge was placed on the forearm for VOP and a NIRS device was distally attached. Slopes for FBF and NIRS parameters were quantified during venous occlusion intervals at rest and during RH. Pearson’s correlations were assessed between VOP and NIRS slopes. Intraclass correlation coefficients (ICC2,1) examined the sex-specific consistency of the slopes at rest. p ≤ 0.05 was considered significant. Results: During RH, FBF was not correlated with O2Hb (r = −0.126), HHb (r = 0.228), tHb (r = 0.061), or HbDiff (r = 0.046). Seemingly, there were no sex differences. Resting FBF and NIRS-derived variables, except for HbDiff, displayed suitable consistency as suggested by the reliability results (ICC2,1 = 0.115–0.577). Conclusions: The NIRS values collected did not match the strain-gauge slopes. Individuals should practice caution when generating blood flow inferences from NIRS-based data during VOP.

Immediate effect of Bhastrika Pranayama on cerebral hemodynamics in patient with depression: A case report

BackgroundDepression is a common mental disorder with increasing prevalence in India, which involves cognitive impairment as well. Pharmacological management of depression has many adverse effects, which provides symptomatic relief to the patients, with little to no improvement in cognitive impairment or cerebral hemodynamics. This necessitates the exploration of complementary and alternative treatment modalities. Yoga, in particular Bhastrika pranyama, has been utilized as a complementary practice for various conditions, but evidence of its impact on depression and cerebral hemodynamics is limited. Case detailsA 66-year-old male, previously diagnosed with depression, was admitted to our inpatient hospital for a holistic approach to his condition, combining yoga and naturopathy as part of his treatment. During his stay, he participated in a ten-minute Bhastrika pranayama intervention, conducted under supervision. To evaluate cerebral hemodynamics, a 16-channel functional near-infrared spectroscopy (fNIRS) device was used and changes in oxygenated hemoglobin (oxyHb), deoxygenated hemoglobin (deoxyHb), and total hemoglobin (Total Hb) was recorded. ResultsFollowing the practice of Bhastrika Pranayama, the results indicated a rise in bilateral oxygenated hemoglobin (OxyHb) levels during and immediately after the practice, particularly in the prefrontal cortex region. Simultaneously, a decrease in deoxygenated hemoglobin (DeoxyHb) was observed during the practice, with a slight subsequent increase after the Bhastrika Pranayama session. ConclusionThese preliminary findings indicate that Bhastrika pranayama may have an immediate positive impact on cerebral hemodynamics in patients with depression. Further research with larger sample sizes and controlled studies is needed to confirm and generalize these observations.

Near-infrared spectroscopy and multivariate analysis as real-time monitoring strategy of TEMPO-mediated oxidation of cellulose fibers from different feedstocks

The regioselective oxidation of the primary hydroxyl groups of cellulose, usually mediated by the (2,2,6,6-tetramethylpiperidin-1-yl)oxyl radical (TEMPO), is highly popular in the scientific literature. However, the lack of efficient monitoring techniques imposes a severe limitation to its upscaling. This work involves a portable, user-friendly near-infrared spectroscopy device, optimized preprocessing techniques, and multivariate calibration to quickly estimate the carboxyl group content of modified cellulose (i.e., the extent of the oxidation). For that, bleached pulps from eucalyptus, pine, hemp, and sisal were submitted to TEMPO-mediated oxidation, varying the dosage of spent oxidizer (NaClO) and thus attaining samples of different values of carboxyl group content. These values were related to near-infrared spectra (908–1676 nm) by Partial Least Squares regression, yielding cross-validation coefficients (RCV2) above 0.97 for wood pulps, 0.95 for sisal pulp, and 0.91 for hemp pulp. Based on the residual prediction deviation, the model for each pulp was found to show good predictability. Nonetheless, the overall regression model, comprising the four different materials, was unreliable. In light of this, spectra were submitted to principal components analysis (PCA), hinting that pulps could be classified in terms of their hemicellulose to cellulose ratio. Considering all the statistical parameters, the overall proposal presented here begins with a PCA—Linear Discriminant Analysis model to classify the sample by its fiber type, subsequently selecting a specific regression model for that class. Overall, the presented models in this work allow the determination of the extent of oxidation of different cellulosic feedstocks, expressed as carboxyl content, in a fast and simple approach using a benchtop near-infrared equipment.

Reference Ranges for Regional Cerebral Oxygen Saturation with Masimo O3 after Birth and Differences with Other Devices.

Cerebral oximetry using near-infrared spectroscopy (NIRS) is a noninvasive optical technology widely used in neonatology. The present study aimed to define reference ranges for cerebral tissue oxygen saturation (crSO2) with a new four-wavelength NIRS device, Masimo O3 oximeter, during immediate transition after birth and compare values with those obtained previously with NIRO 200NX®. This was a prospective observational study using Masimo O3 device to measure crSO2 and regional cerebral fractional tissue oxygen extraction (cFTOE) in healthy term newborns delivered by primary cesarean section, during the 15 minutes after cord clamping. The neonates who required any medical support were excluded. The NIRS sensor was placed on the right forehead. Peripheral oxygen saturation and heart rate were continuously measured by pulse oximetry. Previous studies which established centiles for crSO2 with NIRO 200NX were used for comparison. A total of 44 newborns were included. The median crSO2 and cFTOE (interquartile range) at 2, 5, and 7 minutes was 54% (49-54), 71% (64-86), and 79% (73-84) and 0,25 (0,18-0,33), 0,19 (0,15-0,23), and 0,16 (0,12-0,21), respectively, with no further changes afterwards. The crSO2 measurements were significantly higher with Masimo O3 compared with NIRO-200NX. The present observational study presented reference ranges for crSO2 and cFTOE measured with Masimo O3 oximeter during the immediate neonatal transition. Values obtained with O3 were higher than those obtained with other oximeters. For this reason, crSO2 is device-specific so there must be known reference values for each oximeter to define therapeutic interventions based on crSO2 and assess cerebral oxygenation in clinical studies. · Masimo O3 uses four wavelengths to measure regional oxygen saturation value.. · O3 values of crSO2 and cFTOE differ with other neonatal oximeters at birth.. · Knowledge of reference range of O3 at birth is essential to guide resuscitation..