Noninvasive and fast measurement of blood glucose in vivo by near infrared (NIR) spectroscopy

A near-infrared (NIR) tomography system with spectrally-encoded sources in two wavelength bands was built to quantify the temporal oxyhemoglobin and deoxyhemoglobin contrast in breast tissue at a 20 Hz bandwidth. The system was integrated into a 3 T magnetic resonance (MR) imaging system through a customized breast coil interface for simultaneous optical and MRI acquisition. In this configuration, the MR images provide breast tissue structural information for NIR spectroscopy of adipose and fibro-glandular tissue in breast. Spectral characterization performance of the NIR system was verified through dynamic phantom experiments. Normal human subjects were imaged with finger pulse oximeter (PO) plethysmogram synchronized to the NIR system to provide a frequency-locked reference. Both the raw data from the NIR system and the recovered absorption coefficients of the breast at two wavelengths showed the same frequency of about 1.3 Hz as the PO output. The frequency lock-in approach provided a practical platform for MR-localized recovery of small pulsatile variations of oxyhemoglobin and deoxyhemoglobin in the breast, which are related to the heartbeat and vascular resistance of the tissue.

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Biocellulose Masks as Delivery Systems: A Novel Methodological Approach to Assure Quality and Safety

Cosmetics ◽

10.3390/cosmetics5040066 ◽

2018 ◽

Vol 5 (4) ◽

pp. 66 ◽

Cited By ~ 5

Author(s):

Paola Perugini ◽

Mariella Bleve ◽

Fabiola Cortinovis ◽

Antonio Colpani

Keyword(s):

Light Scattering ◽

Bacterial Cellulose ◽

Near Infrared ◽

Gas Permeability ◽

Methodological Approach ◽

Safety Evaluation ◽

Nir Spectroscopy ◽

Quality And Safety ◽

Multiple Light Scattering

Bacterial cellulose (BC) has become of great interest in recent years, as a delivery system in several areas of application, including food, drugs, and cosmetics, thanks to its exclusive advantages, such as high biocompatibility, water holding capacity, and good gas permeability. The novel approach of the authors has led to a protocol for checking the quality and safety of bacterial cellulose matrices in the manufacture of cosmetic masks. Two non-destructive techniques, near-infrared spectroscopy (NIR) and multiple light scattering (MLS), were used to verify different parameters affecting the quality of BC sheets, allowing cellulose masks to be checked over time. NIR spectroscopy allowed for discovering changes in the water content, depending on filling/packaging procedures, like flat-folding. Multiple light scattering was used to ascertain the stability of solutions in contact with masks. From a clinical standpoint, the cutaneous tolerability of biocellulose masks, and their effect on skin parameters, were evaluated through some specific “in vivo” tests. Also, a safety evaluation during application was conducted through different studies: a short-term one after single application, and a long-term one upon continued use.

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Cerebral oxygen availability by NIR spectroscopy during transient hypoxia in humans

Journal of Applied Physiology ◽

10.1152/jappl.1990.69.3.907 ◽

1990 ◽

Vol 69 (3) ◽

pp. 907-913 ◽

Cited By ~ 68

Author(s):

N. B. Hampson ◽

E. M. Camporesi ◽

B. W. Stolp ◽

R. E. Moon ◽

J. E. Shook ◽

...

Keyword(s):

Heart Rate ◽

Blood Volume ◽

Near Infrared ◽

Cerebral Blood Volume ◽

Minute Ventilation ◽

Nir Spectroscopy ◽

Redox Status ◽

Total Blood ◽

Arterial Ph

The effects of mild hypoxia on brain oxyhemoglobin, cytochrome a,a3 redox status, and cerebral blood volume were studied using near-infrared spectroscopy in eight healthy volunteers. Incremental hypoxia reaching 70% arterial O2 saturation was produced in normocapnia [end-tidal PCO2 (PETCO2) 36.9 +/- 2.6 to 34.9 +/- 3.4 Torr] or hypocapnia (PETCO2 32.8 +/- 0.6 to 23.7 +/- 0.6 Torr) by an 8-min rebreathing technique and regulation of inspired CO2. Normocapnic hypoxia was characterized by progressive reductions in arterial PO2 (PaO2, 89.1 +/- 3.5 to 34.1 +/- 0.1 Torr) with stable PETCO2, arterial PCO2 (PaCO2), and arterial pH and resulted in increases in heart rate (35%) systolic blood pressure (14%), and minute ventilation (5-fold). Hypocapnic hypoxia resulted in progressively decreasing PaO2 (100.2 +/- 3.6 to 28.9 +/- 0.1 Torr), with progressive reduction in PaCO2 (39.0 +/- 1.6 to 27.3 +/- 1.9 Torr), and an increase in arterial pH (7.41 +/- 0.02 to 7.53 +/- 0.03), heart rate (61%), and ventilation (3-fold). In the brain, hypoxia resulted in a steady decline of cerebral oxyhemoglobin content and a decrease in oxidized cytochrome a,a3. Significantly greater loss of oxidized cytochrome a,a3 occurred for a given decrease in oxyhemoglobin during hypocapnic hypoxia relative to normocapnic hypoxia. Total blood volume response during hypoxia also was significantly attenuated by hypocapnia, because the increase in volume was only half that of normocapnic subjects. We conclude that cytochrome a,a3 oxidation level in vivo decreases at mild levels of hypoxia. PaCO is an important determinant of brain oxygenation, because it modulates ventilatory, cardiovascular, and cerebral O2 delivery responses to hypoxia.

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Cerebrovascular responses of the rat brain to noxious stimuli as examined by functional near-infrared whole brain imaging

Journal of Neurophysiology ◽

10.1152/jn.00050.2011 ◽

2012 ◽

Vol 107 (10) ◽

pp. 2853-2865 ◽

Cited By ~ 6

Author(s):

Ji-Wei He ◽

Fenghua Tian ◽

Hanli Liu ◽

Yuan Bo Peng

Keyword(s):

Brain Imaging ◽

Near Infrared ◽

Small Animal ◽

Nir Spectroscopy ◽

Brain Regions ◽

Anterior Cingulate ◽

Hemodynamic Changes ◽

Whole Brain ◽

Brain Hemodynamics

While near-infrared (NIR) spectroscopy has been increasingly used to detect stimulated brain activities with an advantage of dissociating regional oxy- and deoxyhemoglobin concentrations simultaneously, it has not been utilized much in pain research. Here, we investigated and demonstrated the feasibility of using this technique to obtain whole brain hemodynamics in rats and speculated on the functional relevance of the NIR-based hemodynamic signals during pain processing. NIR signals were emitted and collected using a 26-optodes array on rat's dorsal skull surface after the removal of skin. Following the subcutaneous injection of formalin (50 μl, 3%) into a hindpaw, several isolable brain regions showed hemodynamic changes, including the anterior cingulate cortex, primary/secondary somatosensory cortexes, thalamus, and periaqueductal gray ( n = 6). Time courses of hemodynamic changes in respective regions matched with the well-documented biphasic excitatory response. Surprisingly, an atypical pattern (i.e., a decrease in oxyhemoglobin concentration with a concomitant increase in deoxyhemoglobin concentration) was seen in phase II. In a separate group of rats with innocuous brush and noxious pinch of the same area ( n = 11), results confirmed that the atypical pattern occurred more likely in the presence of nociception than nonpainful stimulation, suggesting it as a physiological substrate when the brain processes pain. In conclusion, the NIR whole brain imaging provides a useful alternative to study pain in vivo using small-animal models. Our results support the notion that neurovascular response patterns depend on stimuli, bringing attention to the interpretation of vascular-based neuroimaging data in studies of pain.

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Monitoring the performance of a broad-based calibration for measuring the nutritive value of two independent populations of pasture using near infrared reflectance (NIR) spectroscopy

Australian Journal of Experimental Agriculture ◽

10.1071/ea9910205 ◽

1991 ◽

Vol 31 (2) ◽

pp. 205 ◽

Cited By ~ 27

Author(s):

KF Smith ◽

PC Flinn

Keyword(s):

Nutritive Value ◽

Near Infrared ◽

Linear Regression Analysis ◽

Spectral Characteristics ◽

Nir Spectroscopy ◽

Cost Effective ◽

Multiple Linear Regression Analysis ◽

Infrared Reflectance ◽

Near Infrared Reflectance

Near infrared reflectance (NIR) spectroscopy is a rapid and cost-effective method for the measurement of organic constituents of agricultural products. NIR is widely used to measure feed quality around the world and is gaining acceptance in Australia. This study describes the development of an NIR calibration to measure crude protein (CP), predicted in vivo dry matter digestibility (IVDMD) and neutral detergent fibre (NDF) in temperate pasture species grown in south-western Victoria. A subset of 116 samples was selected on the basis of spectral characteristics from 461 pasture samples grown in 1987-89. Several grass and legume species were present in the population. Stepwise multiple linear regression analysis was used on the 116 samples to develop calibration equations with standard errors of 0.8,2.3 and 2.2% for CP, NDF and IVDMD, respectively. When these equations were tested on 2 independent pasture populations, a significant bias existed between NIR and reference values for 2 constituents in each population, indicating that the calibration samples did not adequately represent the new populations for these constituents. The results also showed that the H statistic alone was inadequate as an indicator of equation performance. It was confirmed that it was possible to develop a broad-based calibration to measure accurately the nutritive value of closed populations of temperate pasture species. For the resulting equations to be used for analysis of other populations, however, they must be monitored by comparing reference and NIR analyses on a small number of samples to check for the presence of bias or a significant increase in unexplained error.

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Influence of Blood Glucose Level on the Scattering Coefficient of the Skin in Near-Infrared Spectroscopy

ASME/JSME 2011 8th Thermal Engineering Joint Conference ◽

10.1115/ajtec2011-44471 ◽

2011 ◽

Cited By ~ 2

Author(s):

Sachiko Kessoku ◽

Katsuhiko Maruo ◽

Shinpei Okawa ◽

Kazuto Masamoto ◽

Yukio Yamada

Keyword(s):

Optical Properties ◽

Infrared Spectroscopy ◽

Blood Glucose ◽

Blood Glucose Level ◽

Glucose Level ◽

Near Infrared Spectroscopy ◽

Near Infrared ◽

Monitoring Methods ◽

Absorbance Spectra

Various non-invasive glucose monitoring methods using near-infrared spectroscopy have been investigated although no method has been successful so far. Our previous study has proposed a new promising method utilizing numerically generated absorbance spectra instead of the experimentally acquired absorbance spectra. The method suggests that the correct estimation of the optical properties is very important for numerically generating the absorbance spectra. The purpose of this study is to measure the change in the optical properties of the skin with the change in the blood glucose level in vivo. By measuring the reflectances of light incident on the skin surface at two distances from the incident point, the optical properties of the skin can be estimated. The estimation is a kind of the inverse problem based on the simulation of light propagation in the skin. Phantom experiments have verified the method and in vivo experiments are to be performed.

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Investigation of Noninvasive in vivo Blood Hematocrit Measurement Using NIR Reflectance Spectroscopy and Partial Least-Squares Regression

Applied Spectroscopy ◽

10.1366/0003702001949258 ◽

2000 ◽

Vol 54 (2) ◽

pp. 294-299 ◽

Cited By ~ 30

Author(s):

Songbiao Zhang ◽

Babs R. Soller ◽

Shubjeet Kaur ◽

Kristen Perras ◽

Thomas J. Vander Salm

Keyword(s):

Least Squares ◽

Partial Least Squares ◽

Near Infrared ◽

Multivariate Calibration ◽

Nir Spectroscopy ◽

Study Groups ◽

Patient Specific ◽

Least Squares Regression ◽

Fiber Optic Probe

Hematocrit (Hct), the volume percent of red cells in blood, is monitored routinely for blood donors, surgical patients, and trauma victims and requires blood to be removed from the patient. An accurate, noninvasive method for directly measuring hematocrit on patients is desired for these applications. The feasibility of noninvasive hematocrit measurement by using near-infrared (NIR) spectroscopy and partial least-squares (PLS) techniques was investigated, and methods of in vivo calibration were examined. Twenty Caucasian patients undergoing cardiac surgery on cardiopulmonary bypass were randomly selected to form two study groups. A fiber-optic probe was attached to the patient's forearm, and NIR spectra were continuously collected during surgery. Blood samples were simultaneously collected and reference Hct measurements were made with the spun capillary method. PLS multivariate calibration techniques were applied to investigate the relationship between spectral and Hct changes. Single patient calibration models were developed with good cross-validated estimation of accuracy (∼ 1 Hct%) and trending capability for most patients. Time-dependent system drift, patient temperature, and venous oxygen saturation were not correlated with the hematocrit measurements. Multi-subject models were developed for prediction of independent subjects. These models demonstrated a significant patient-specific offset that was shown to be partially related to spectrometer drift. The remaining offset is attributed to the large spectral variability of patient tissue, and a significantly larger set of patients would be required to adequately model this variability. After the removal of the offset, the cross-validated estimation of accuracy is 2 Hct%.

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Theranostic Approach for Cancer Treatment: Multifunctional Gold Nanorods for Optical Imaging and Photothermal Therapy

Journal of Nanomaterials ◽

10.1155/2015/646713 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 27

Author(s):

Oshra Betzer ◽

Rinat Ankri ◽

Menachem Motiei ◽

Rachela Popovtzer

Keyword(s):

Gold Nanorods ◽

Photothermal Therapy ◽

Near Infrared ◽

Detection Method ◽

Nir Spectroscopy ◽

Surgical Excision ◽

Spectral Shift ◽

Tissue Destruction ◽

Shift Analysis

A critical problem in the treatment of cancer is the inability to identify microsized tumors and treat them without normal tissue destruction. While surgical excision of tumors is highly effective, residual micrometastases and remaining positive margins are the main cause of recurrence. In this study, we propose a theranostic approach for the detection and therapy of head and neck cancer (HNC). We developed a plasmonic-based nanoplatform for combined, ultrasensitivein vivospectroscopic detection and targeted therapy of HNC. This detection method involves near-infrared (NIR) spectroscopy of gold nanorods (GNRs) that selectively target and attach to squamous cell carcinoma HNC cells, through an immune complex. Diagnosis is based on a spectral shift analysis, which is generated by interparticle-plasmon-resonance patterns of the specifically targeted GNRs. Additionally, the ability to design the GNRs to strongly absorb light in the NIR region enables efficient irradiation of these GNRs, for selective photothermal therapy (PTT) of the cancer cells. We expect this targeted, noninvasive, and nonionizing spectroscopic detection method to provide a highly sensitive and simple diagnostic tool for micrometastasis. In addition, the concomitant development of targeted PTT, based on specific cancer markers, may pave the way for tailoring effective therapy for patients, toward an era of personalized medicine.

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A New, Non-Invasive in vivo Optical Blood Glucose Measurement Technique Using Near-Infrared Radiation (“Pulse Glucometry”) and a Proposal for “Pulse Hemo-Photometry” Blood Constituent Measurements

Technological Advancements in Biomedicine for Healthcare Applications - Advances in Bioinformatics and Biomedical Engineering ◽

10.4018/978-1-4666-2196-1.ch003 ◽

2012 ◽

pp. 18-26

Author(s):

Mitsuhiro Ogawa ◽

Takehiro Yamakoshi ◽

Kenta Matsumura ◽

Kosuke Motoi ◽

Ken-Ichi Yamakoshi

Keyword(s):

Blood Glucose ◽

Optical Density ◽

Near Infrared ◽

Blood Glucose Measurement ◽

Blood Constituents ◽

Non Invasive ◽

Arterial Blood ◽

Multiple Wavelengths ◽

Blood Constituent

A recently proposed optical method for a non-invasive in vivo blood glucose level (BGL) measurement named “pulse glucometry” is introduced. This method is based on near-infrared living body spectroscopy to accurately obtain blood information. The remarkable feature of the method is the measurement of both the total transmitted radiation spectra in wavelength ? (I?) and the cardiac-related pulsatile component (?I?). When ?I? is superimposed on I?, the differential optical density (?OD?), which includes only arterial blood information, is obtained, thus avoiding interference from living tissues other than arterial blood. Another feature is the ability to measure the differential optical density (?OD?) in multiple wavelengths to avoid interference from blood constituents other than the target blood chemical (glucose). To support this methodology, a very fast near-infrared spectroscopic system was developed to obtain a photoplethysmographic cardiac signal with a resolution of 8 nm over a wavelength range of 900 to 1700 nm at a 100 Hz sampling frequency. An example of an in vivo BGL measurement is shown and indicates good prediction capabilities. This method can be expanded to the measurement of other blood constituents.

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