Abstract 10029: Near-Infrared Spectroscopy Assessments for the Prediction of Neurological Outcome in the Rat Model of Cardiac Arrest

Introduction: Clinical studies have demonstrated that the initial rapid decrement in regional cerebral oxygen saturation (rSO 2 ) level by near-infrared spectroscopy shortly after ROSC was associated with good neurological outcomes. Aim: To evaluate whether the timing of rSO 2 decline shortly after ROSC reflects the severity of brain injury in a well-established rat model of CA/CPR. Methods: We used a total of 85 Wister SD rats (male, 435.2±3.1 g).To produce variable severities of brain injury, CA was induced by different asphyxial times and resuscitated by finger chest compressions and mechanical ventilation. Survival time was recorded for 72 hours after ROSC. Daily neurofunctional scores (NFS) were evaluated by an investigator blinded to the experiments. Electroencephalography (EEG), immunohistochemistry, plasma IL-6, and the gene expressions of cytokines (IL-1, IL-6, TNF-α, HMGB-1) and mitochondrial fission-related proteins (Dnm1L, Fis1, Mief1) in the brain were also evaluated. Result: Animals in the 12-min CA group exhibited a longer time to EEG recovery after CA/CPR compared with the 6-min group (P<.0001), suggesting the longer CA duration induces a delayed brain electrical recovery. Time from ROSC to achieving the initial minimum rSO 2 value (defined as T nadir ) was significantly prolonged as CA time increased; 15.3 ± 2.3, 32.1 ± 22.1, and 44.0 ± 2.8 min in 6, 9, and 12min CA, respectively (ANOVA: P<.0001). T nadir cut-off of 24-min provided the optimal sensitivity and specificity for predicting good neurologic outcomes (NFS≥60%) at 72 hours after ROSC (AUC, 0.88; sensitivity, 89%; specificity, 86%; P<.01). T nadir showed a better predictive power for the good neurological outcome compared with plasma IL-6. Immunohistochemistry at 24 hours post-CA revealed that FJB-positive degenerating neurons in cortex, caudoputamen, and hippocampus were conspicuous in animals with T nadir >24-min, but not in animals with T nadir ≤24-min. Animals with T nadir >24 tended to have a higher gene expression level of IL-6 in the brain at 2 hours post-ROSC compared to those with T nadir ≤24. T nadir did not show associations with other inflammatory or mitochondrial fission markers. Conclusion: T nadir can be a novel predictor for a good neurological outcome after CA/CPR.

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Real-Time Brain Monitoring by Near-Infrared Spectroscopy Predicts Neurological Outcome after Cardiac Arrest and Resuscitation in Rats: A Proof of Concept Study of a Novel Prognostic Measure after Cardiac Arrest

Journal of Clinical Medicine ◽

10.3390/jcm11010131 ◽

2021 ◽

Vol 11 (1) ◽

pp. 131

Author(s):

Ryosuke Takegawa ◽

Kei Hayashida ◽

Tai Yin ◽

Rishabh C. Choudhary ◽

Santiago J. Miyara ◽

...

Keyword(s):

Cardiac Arrest ◽

Brain Injury ◽

Near Infrared ◽

Mitochondrial Fission ◽

Spontaneous Circulation ◽

Gene Expressions ◽

Dynamic Changes ◽

Neurological Outcomes ◽

Fluoro Jade B ◽

The Brain

Clinical studies have demonstrated that dynamic changes in regional cerebral oxygen saturation (rSO2) after cardiac arrest (CA) and cardiopulmonary resuscitation (CPR) have a role in predicting neurological outcomes after the return of spontaneous circulation (ROSC). Our study evaluated whether the timing of rSO2 decline shortly after CPR reflects the severity of brain injury in a rat model of CA. Rats were subjected to different durations of asphyxia to produce variable severities of brain injury, due to CA. Time from ROSC to achieving the initial minimum rSO2 was defined as Tnadir. A Tnadir cut-off of 24 min had optimal sensitivity and specificity for predicting good neurological outcomes at 72 h after ROSC (AUC, 0.88; sensitivity, 89%; specificity, 86%; p < 0.01). Immunohistochemistry at 72 h post-CA revealed that the number of Fluoro-Jade B positive degenerating neurons in the hippocampus CA1 sector were markedly higher in animals with Tnadir > 24 min than that in animals with Tnadir ≤ 24 min. There was no difference in the gene expressions of cytokines and mitochondrial fission proteins in the brain at 2 h after ROSC between rats with Tnadir > 24 min and with Tnadir ≤ 24 min. In conclusion, Tnadir can be a novel predictor of good neurological outcomes after CA/CPR.

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Near-Infrared Spectroscopy (NIRS) in Traumatic Brain Injury (TBI)

Sensors ◽

10.3390/s21051586 ◽

2021 ◽

Vol 21 (5) ◽

pp. 1586

Author(s):

María Roldán ◽

Panayiotis A. Kyriacou

Keyword(s):

Traumatic Brain Injury ◽

Infrared Spectroscopy ◽

Brain Injury ◽

Near Infrared Spectroscopy ◽

Near Infrared ◽

Cerebral Oxygenation ◽

Noninvasive Monitoring ◽

Infrared Light ◽

Cochrane Library ◽

The Brain

Traumatic brain injury (TBI) occurs when a sudden trauma causes damage to the brain. TBI can result when the head suddenly and violently impacts an object or when an object pierces the skull and enters brain tissue. Secondary injuries after traumatic brain injury (TBI) can lead to impairments on cerebral oxygenation and autoregulation. Considering that secondary brain injuries often take place within the first hours after the trauma, noninvasive monitoring might be helpful in providing early information on the brain’s condition. Near-infrared spectroscopy (NIRS) is an emerging noninvasive monitoring modality based on chromophore absorption of infrared light with the capability of monitoring perfusion of the brain. This review investigates the main applications of NIRS in TBI monitoring and presents a thorough revision of those applications on oxygenation and autoregulation monitoring. Databases such as PubMed, EMBASE, Web of Science, Scopus, and Cochrane library were utilized in identifying 72 publications spanning between 1977 and 2020 which were directly relevant to this review. The majority of the evidence found used NIRS for diagnosis applications, especially in oxygenation and autoregulation monitoring (59%). It was not surprising that nearly all the patients were male adults with severe trauma who were monitored mostly with continue wave NIRS or spatially resolved spectroscopy NIRS and an invasive monitoring device. In general, a high proportion of the assessed papers have concluded that NIRS could be a potential noninvasive technique for assessing TBI, despite the various methodological and technological limitations of NIRS.

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Mismatch between Tissue Partial Oxygen Pressure and Near-Infrared Spectroscopy Neuromonitoring of Tissue Respiration in Acute Brain Trauma: The Rationale for Implementing a Multimodal Monitoring Strategy

International Journal of Molecular Sciences ◽

10.3390/ijms22031122 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1122

Author(s):

Mario Forcione ◽

Mario Ganau ◽

Lara Prisco ◽

Antonio Maria Chiarelli ◽

Andrea Bellelli ◽

...

Keyword(s):

Infrared Spectroscopy ◽

Near Infrared Spectroscopy ◽

Oxygen Pressure ◽

Near Infrared ◽

Optical Signal ◽

Brain Trauma ◽

Partial Oxygen Pressure ◽

Tissue Respiration ◽

The Brain ◽

Partial Oxygen

The brain tissue partial oxygen pressure (PbtO2) and near-infrared spectroscopy (NIRS) neuromonitoring are frequently compared in the management of acute moderate and severe traumatic brain injury patients; however, the relationship between their respective output parameters flows from the complex pathogenesis of tissue respiration after brain trauma. NIRS neuromonitoring overcomes certain limitations related to the heterogeneity of the pathology across the brain that cannot be adequately addressed by local-sample invasive neuromonitoring (e.g., PbtO2 neuromonitoring, microdialysis), and it allows clinicians to assess parameters that cannot otherwise be scanned. The anatomical co-registration of an NIRS signal with axial imaging (e.g., computerized tomography scan) enhances the optical signal, which can be changed by the anatomy of the lesions and the significance of the radiological assessment. These arguments led us to conclude that rather than aiming to substitute PbtO2 with tissue saturation, multiple types of NIRS should be included via multimodal systemic- and neuro-monitoring, whose values then are incorporated into biosignatures linked to patient status and prognosis. Discussion on the abnormalities in tissue respiration due to brain trauma and how they affect the PbtO2 and NIRS neuromonitoring is given.

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Near-Infrared Spectroscopy Monitoring of Cerebral Oxygenation and Influencing Factors in Neonates from High-Altitude Areas

Neonatology ◽

10.1159/000514403 ◽

2021 ◽

pp. 1-6

Author(s):

Bi Ze ◽

Lili Liu ◽

Ge Sang Yang Jin ◽

Minna Shan ◽

Yuehang Geng ◽

...

Keyword(s):

Heart Disease ◽

Infrared Spectroscopy ◽

Brain Injury ◽

Oxygen Saturation ◽

High Altitude ◽

Near Infrared Spectroscopy ◽

Near Infrared ◽

Cerebral Oxygenation ◽

Low Altitude ◽

Normal Neonates

Background: Accurate detection of cerebral oxygen saturation (rSO2) may be useful for neonatal brain injury prevention, and the normal range of rSO2 of neonates at high altitude remained unclear. Objective: To compare cerebral rSO2 and cerebral fractional tissue oxygen extraction (cFTOE) at high-altitude and low-altitude areas in healthy neonates and neonates with underlying diseases. Methods: 515 neonates from low-altitude areas and 151 from Tibet were enrolled. These neonates were assigned into the normal group, hypoxic-ischemic encephalopathy (HIE) group, and other diseases group. Near-infrared spectroscopy was used to measure rSO2 in neonates within 24 h after admission. The differences of rSO2, pulse oxygen saturation (SpO2), and cFTOE levels were compared between neonates from low- and high-altitude areas. Results: (1) The mean rSO2 and cFTOE levels in normal neonates from Tibet were 55.0 ± 6.4% and 32.6 ± 8.5%, significantly lower than those from low-altitude areas (p < 0.05). (2) At high altitude, neonates with HIE, pneumonia (p < 0.05), anemia, and congenital heart disease (p < 0.05) have higher cFTOE than healthy neonates. (3) Compared with HIE neonates from plain areas, neonates with HIE at higher altitude had lower cFTOE (p < 0.05), while neonates with heart disease in plateau areas had higher cFTOE than those in plain areas (p < 0.05). Conclusions: The rSO2 and cFTOE levels in normal neonates from high-altitude areas are lower than neonates from the low-altitude areas. Lower cFTOE is possibly because of an increase in blood flow to the brain, and this may be adversely affected by disease states which may increase the risk of brain injury.

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

10.1101/2021.02.13.431051 ◽

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.

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Brain–Computer Interfacing Using Functional Near-Infrared Spectroscopy (fNIRS)

Biosensors ◽

10.3390/bios11100389 ◽

2021 ◽

Vol 11 (10) ◽

pp. 389

Author(s):

Kogulan Paulmurugan ◽

Vimalan Vijayaragavan ◽

Sayantan Ghosh ◽

Parasuraman Padmanabhan ◽

Balázs Gulyás

Keyword(s):

Infrared Spectroscopy ◽

Near Infrared Spectroscopy ◽

Brain Function ◽

Near Infrared ◽

Functional Near Infrared Spectroscopy ◽

Non Invasive ◽

Neuron Function ◽

Brain Computer Interfacing ◽

The Brain ◽

Computer Interfacing

Functional Near-Infrared Spectroscopy (fNIRS) is a wearable optical spectroscopy system originally developed for continuous and non-invasive monitoring of brain function by measuring blood oxygen concentration. Recent advancements in brain–computer interfacing allow us to control the neuron function of the brain by combining it with fNIRS to regulate cognitive function. In this review manuscript, we provide information regarding current advancement in fNIRS and how it provides advantages in developing brain–computer interfacing to enable neuron function. We also briefly discuss about how we can use this technology for further applications.

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