Sankar Seramani1, Bhanu Prakash K.N. 1, Sanjay K. Verma1, Kian Chye Ng2, Enci Mary Kan2, Gopalan V. 1, Michael N. 1, Yaligar J1, Graham S. 3, Jia Lu2, C. Childs4, Sendhil S. Velan1, 5
1Laboratory of Molecular Imaging, Singapore Bioimaging Consortium, Singapore, Singapore; 2Defence Medical and Environmental Research Institute, DSO National Laboratories, Singapore, Singapore; 3Department of Psychology, National University of Singapore, Singapore, Singapore; 4Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore; 5Clinical Imaging Research Centre, Agency for Science, Technology and Research, Singapore, Singapore
Magnetic resonance spectroscopy based non-invasive temperature measurement of an in-vivo brain is one of the most preferred ways of mapping the temperature of the brain. This is based on the relationship between water resonant frequency of the tissue and the actual temperature of the tissue. Hence, it is necessary to calibrate/derive the relationship between the chemical shift of the water and the temperature, by using the brain metabolites phantom for the given field strength of the magnet. Traumatic Brain Injuries (TBI) causes increase in brain temperature due to inflammation and other neuroprotective mechanism. Monitoring the region specific brain temperature in-vivo helps in predicting the prognosis of the treatment in the TBI subjects. We calibrated the in-house designed brain metabolite phantom at different temperatures on a 7 Tesla scanner and also explored the changes in brain temperature of TBI rats at different time-points. The water chemical shift showed a linear dependence on temperature in the phantom calibration and increased brain temperature was observed in TBI rats until Day-3, which decreased subsequently.