TY - JOUR
T1 - Diffuse near-infrared reflectance spectroscopy during heatstroke in a mouse model
T2 - Pilot study
AU - Abookasis, David
AU - Zafrir, Elad
AU - Nesher, Elimelech
AU - Pinhasov, Albert
AU - Sternklar, Shmuel
AU - Mathews, Marlon S.
N1 - Funding Information:
Authors would like to gratefully acknowledge the anonymous reviewers’ for all their valuable comments and useful suggestions making the manuscript clearer and more focused. D. Abookasis also gratefully acknowledges both Ariel University and the Israeli Ministry of Absorption’s for their support as part of the “returning scientists” program.
PY - 2012/10
Y1 - 2012/10
N2 - Heatstroke, a form of hyperthermia, is a life-threatening condition characterized by an elevated core body temperature that rises above 40°C (104°F) and central nervous system dysfunction that results in delirium, convulsions, or coma. Without emergency treatment, the victim lapses into a coma and death soon follows. The study presented was conducted with a diffuse reflectance spectroscopy (DRS) setup to assess the effects of brain dysfunction that occurred during heatstroke in mice model (n = 6). It was hypothesized that DRS can be utilized in small animal studies to monitor change in internal brain tissue temperature during heatstroke injury since it induces a sequence of pathologic changes that change the tissue composition and structure. Heatstroke was induced by exposure of the mice body under general anesthesia, to a high ambient temperature. A type of DRS in which the brain tissue was illuminated through the intact scalp with a broadband light source and diffuse reflected spectra was employed, taking in the spectral region between 650 and 1000 nm and acquired at an angle of 90 deg at a position on the scalp ∼12 mm from the illumination site. The temperature at the onset of the experiment was ∼34°C (rectal temperature) with increasing intervals of 1°C until mouse death. The increase in temperature caused optical scattering signal changes consistent with a structural alteration of brain tissue, ultimately resulting in death. We have found that the peak absorbance intensity and its second derivative at specific wavelengths correlate well with temperature with an exponential dependence. Based on these findings, in order to estimate the influence of temperature on the internal brain tissue a reflectanceerature index was established and was seen to correlate as well with measured temperature. Overall, results indicate variations in neural tissue properties during heatstroke and the feasibility to monitor and assess internal temperature variations using DRS. Although several approaches have described the rise in temperature and its impact on tissue, to the best of our knowledge no information is available describing the ability to monitor temperature during heatstroke with DRS. The motivation of this study was to successfully describe this ability.
AB - Heatstroke, a form of hyperthermia, is a life-threatening condition characterized by an elevated core body temperature that rises above 40°C (104°F) and central nervous system dysfunction that results in delirium, convulsions, or coma. Without emergency treatment, the victim lapses into a coma and death soon follows. The study presented was conducted with a diffuse reflectance spectroscopy (DRS) setup to assess the effects of brain dysfunction that occurred during heatstroke in mice model (n = 6). It was hypothesized that DRS can be utilized in small animal studies to monitor change in internal brain tissue temperature during heatstroke injury since it induces a sequence of pathologic changes that change the tissue composition and structure. Heatstroke was induced by exposure of the mice body under general anesthesia, to a high ambient temperature. A type of DRS in which the brain tissue was illuminated through the intact scalp with a broadband light source and diffuse reflected spectra was employed, taking in the spectral region between 650 and 1000 nm and acquired at an angle of 90 deg at a position on the scalp ∼12 mm from the illumination site. The temperature at the onset of the experiment was ∼34°C (rectal temperature) with increasing intervals of 1°C until mouse death. The increase in temperature caused optical scattering signal changes consistent with a structural alteration of brain tissue, ultimately resulting in death. We have found that the peak absorbance intensity and its second derivative at specific wavelengths correlate well with temperature with an exponential dependence. Based on these findings, in order to estimate the influence of temperature on the internal brain tissue a reflectanceerature index was established and was seen to correlate as well with measured temperature. Overall, results indicate variations in neural tissue properties during heatstroke and the feasibility to monitor and assess internal temperature variations using DRS. Although several approaches have described the rise in temperature and its impact on tissue, to the best of our knowledge no information is available describing the ability to monitor temperature during heatstroke with DRS. The motivation of this study was to successfully describe this ability.
KW - Absorbance
KW - Cerebral hemodynamics
KW - Diffuse reflectance
KW - Heatstroke
KW - Optical properties
UR - http://www.scopus.com/inward/record.url?scp=84876592824&partnerID=8YFLogxK
U2 - 10.1117/1.JBO.17.10.105009
DO - 10.1117/1.JBO.17.10.105009
M3 - ???researchoutput.researchoutputtypes.contributiontojournal.article???
C2 - 23085983
AN - SCOPUS:84876592824
SN - 1083-3668
VL - 17
JO - Journal of Biomedical Optics
JF - Journal of Biomedical Optics
IS - 10
M1 - 105009
ER -