| 1. |
- Krite Svanberg, Emilie, et al.
(författare)
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Diode laser spectroscopy for non-invasive monitoring of oxygen in the lungs of newborn infants.
- 2016
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Ingår i: Pediatric Research. - : Springer Science and Business Media LLC. - 1530-0447 .- 0031-3998. ; 79, s. 621-628
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Tidskriftsartikel (refereegranskat)abstract
- Newborn infants have pulmonary disorders with abnormal gas distribution, e. g. respiratory distress syndrome. Pulmonary radiography is the clinical routine for diagnosis. Our aim was to investigate a novel non-invasive optical technique for rapid non-radiographic bedside detection of oxygen gas in the lungs of full-term newborn infants.
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| 2. |
- Lundin, Patrik, et al.
(författare)
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Gas Monitoring in Human Body Cavities Using Non-Intrusive Diode Laser Absorption Spectroscopy
- 2012
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Ingår i: 2012 Asia Communications and Photonics Conference. - : IEEE. - 2162-108X. ; , s. 4-7
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Konferensbidrag (refereegranskat)abstract
- Diode laser absorption spectroscopy was utilized for non-intrusive assessment of gas content in human body cavities, including intestines and lungs of a new-born, the mastoid bone, and sinus cavities for monitoring sinusitis recovery in adults.
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| 3. |
- Lundin, Patrik, et al.
(författare)
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Non-invasive gas monitoring in newborn infants using diode laser absorption spectroscopy: A case study
- 2012
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Ingår i: Optical Diagnostics and Sensing XII: Toward Point-of-Care Diagnostics; and Design and Performance Validation of Phantoms Used in Conjunction with Optical Measurement of Tissue IV. - : SPIE. - 1996-756X .- 0277-786X. ; 8229
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Konferensbidrag (refereegranskat)abstract
- Non-invasive diode laser spectroscopy was, for the first time, used to assess gas content in the intestines and the lungs of a new-born, 4 kg, baby. Two gases, water vapor and oxygen, were studied with two low-power tunable diode lasers, illuminating the surface skin tissue and detecting the diffusely emerging light a few centimeters away. The light, having penetrated into the tissue, had experienced absorption by gas located in the lungs and in the intestines. Very distinct water vapor signals were obtained from the intestines while imprint from oxygen was lacking, as expected. Detectable, but minor, signals of water vapor were also obtained from the lungs, illuminating the armpit area and detecting below the collar bone. Water vapor signals were seen but again oxygen signals were lacking, now due to the difficulties of penetration of the oxygen probing light into the lungs of this full-term baby. Ultra-sound images were obtained both from the lungs and from the stomach of the baby. Based on dimensions and our experimental findings, we conclude, that for early pre-term babies, also oxygen should be detectable in the lungs, in addition to intestine and lung detection of water vapor. The present paper focuses on the studies of the intestines while the lung studies will be covered in a forthcoming paper.
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| 4. |
- Lundin, Patrik, et al.
(författare)
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Noninvasive monitoring of gas in the lungs and intestines of newborn infants using diode lasers: feasibility study.
- 2013
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Ingår i: Journal of Biomedical Optics. - 1083-3668. ; 18:12
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Tidskriftsartikel (refereegranskat)abstract
- ABSTRACT. Preterm newborn infants have a high morbidity rate. The most frequently affected organs where free gas is involved are the lungs and intestines. In respiratory distress syndrome, both hyperexpanded and atelectatic (collapsed) areas occur, and in necrotizing enterocolitis, intramural gas may appear in the intestine. Today, these conditions are diagnosed with x-ray radiography. A bed-side, rapid, nonintrusive, and gas-specific technique for in vivo gas sensing would improve diagnosis. We report the use of noninvasive laser spectroscopy, for the first time, to assess gas content in the lungs and intestines of three full-term infants. Water vapor and oxygen were studied with two low-power diode lasers, illuminating the skin and detecting light a few centimeters away. Water vapor was easily detected in the intestines and was also observed in the lungs. The relatively thick chest walls of the infants prevented detection of the weaker oxygen signal in this study. However, results from a previous phantom study, together with scaling of the results presented here to the typical chest-wall thickness of preterm infants, suggest that oxygen also should be detectable in their lungs.
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| 5. |
- Sahlberg, Anna-Lena, et al.
(författare)
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Gas in Scattering Media Absorption Spectroscopy on Small and Large Scales: Towards the Extension of Lung Spectroscopic Monitoring to Adults
- 2021
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Ingår i: Translational Biophotonics. - : Wiley. - 2627-1850.
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Tidskriftsartikel (refereegranskat)abstract
- Numerous natural materials are porous, contain free gas, and are scattering light strongly. Scattering brings about a strong trapping of light and an associated prolonged transit time for photons through a medium. In contrast to the matrix materials, gas enclosures require very narrow‐band laser radiation for probing. We have in the present study used the gas in scattering media absorption spectroscopy (GASMAS) method to study free oxygen in thin (cm) samples utilizing a tunable diode laser, while a pulsed dye laser was employed in corresponding measurements on larger samples, up to the meter scale. Time‐resolved spectroscopy was in both cases used to assess the temporal distribution of the detected photons, mapping the path lengths through the media, which ranged between few centimeters up to 100 m. This study explores the feasibility to extend recent successful monitoring of gases in neonatal infant lungs to the case of larger children or even adults, which could have very important applications, for example, in ventilator setting optimization for severely ill patients, suffering, for example, from SARS‐CoV‐2. The conclusion of our work is that this goal most realistically can be reached by applying intra‐tracheal laser light illumination at the 1 W power level, employing a tapered amplifier, injected with a distributed feed‐back diode‐laser oscillator output and combined with wavelength‐modulation spectroscopy.
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| 6. |
- Svanberg, Emilie Krite, et al.
(författare)
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Non-invasive monitoring of oxygen in the lungs of newborn infants using diode laser spectroscopy
- 2016
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Ingår i: Cancer Imaging and Therapy, CANCER 2016. - 9781943580101 ; Part F13-CANCER 2016
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Konferensbidrag (refereegranskat)abstract
- The main purpose of this study was to investigate a novel non-invasive optical technique for rapid bedside detection of oxygen gas in the lungs of full-term newborn infants. The results suggest that the technique will be clinically useful as a diagnostic and monitoring tool for infants with lung disorders.
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| 7. |
- Bargigia, Ilaria, et al.
(författare)
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Diffuse optical techniques applied to wood characterisation
- 2013
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Ingår i: Journal of Near Infrared Spectroscopy. - : SAGE Publications. - 0967-0335 .- 1751-6552. ; 21:4, s. 259-268
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Tidskriftsartikel (refereegranskat)abstract
- We propose an optical method for non-invasive characterisation of wood samples based on two optical techniques: time-resolved diffuse optical spectroscopy and gas in scattering media absorption spectroscopy. While the latter is sensitive to gases present inside wood pores, the former extracts information on the bulk material regarding light scattering and absorption. Measurements on spruce samples, cut along different wood fibre directions, are presented to show an example of the advantages of this combined approach: by applying these two non-destructive techniques together, in fact, relevant information on wood such as porosity, permeability and moisture content can be assessed. Furthermore, the chemical composition, internal structure and the anisotropy due to the wood fibres can be investigated.
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| 8. |
- Barup, Kerstin, et al.
(författare)
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Multi-disciplinary lidar applications
- 2010
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Ingår i: Laser Applications to Chemical, Security and Environmental Analysis, LACSEA 2010. - 2162-2701. - 9781557528803
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Konferensbidrag (refereegranskat)abstract
- Lidar is a powerful technique normally associated with atmospheric monitoring. However, lidar techniques, also of the laser-induced fluorescence and laser-induced breakdown spectroscopy varieties, provide many new possibilities in unconventional fields including cultural heritage and ecological applications.
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| 9. |
- Brydegaard, Mikkel, et al.
(författare)
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Feasibility study: fluorescence lidar for remote bird classification
- 2010
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Ingår i: Applied Optics. - 2155-3165. ; 49:24, s. 4531-4544
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Tidskriftsartikel (refereegranskat)abstract
- We present a method for remote classification of birds based on eye-safe fluorescence lidar techniques. Mechanisms of quenching are discussed. Plumage reflectance is related to plumage fluorescence. Laboratory measurements on reflectance and fluorescence are presented, as well as test-range measurements. Also we present examples of birds' in-flight lidar returns. The methods are suitable for studies of night migrating species and high-altitude classification with implications for the detailed understanding of bird migration and global virus spread. (C) 2010 Optical Society of America
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| 10. |
- Guan, Zuguang, et al.
(författare)
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Assessment of photon migration in scattering media using heterodyning techniques with a frequency modulated diode laser.
- 2009
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Ingår i: Optics Express. - 1094-4087. ; 17:18, s. 16291-16299
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Tidskriftsartikel (refereegranskat)abstract
- A novel technique for studying photon propagation in scattering media is proposed and demonstrated, as is believed, for the first time. Photons propagating through the medium, from a frequency-ramped single-mode diode laser, meet a reference beam from the same source, at a common detector, and beat frequencies corresponding to various temporal delays are observed by heterodyne techniques. Fourier transformation directly yields the temporal dispersion curve. Proof-of-principle experiments on polystyrene foam and a tissue phantom suggest, that the new method, when fully developed, may favorably compete with the more complex time-correlated single-photon counting (TCSPC) and the phase-shift methods, now much employed.
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