Jan Weis1, Lucian Covaciu2, Sten Rubertsson2, Mats Allers3, Anders Lunderquist4, Hkan Ahlstrm5
1Dept of Radiology, Uppsala University Hospital, Uppsala, Uppland, Sweden; 2Dept Surgical Sciences, Anesthesiology and Intensive Care, Uppsala University Hospital, Uppsala, Uppland, Sweden; 3Clinical Sciences, Div. of Thoracic Surgery, Lund University Hospital, Lund, Skane, Sweden; 4Clinical Sciences, Div. of Exp. Brain Research, Lund University Hospital, Lund, Skane, Sweden; 5Dept. of Radiology, Uppsala University Hospital, Uppsala, Uppland, Sweden
Decrease of the pigs brain temperature (~3 oC in 15 minutes) was induced by intranasal cooling. Conventional MRS methods are unsuitable for monitoring of such temperature changes because of poor spatial resolution and long acquisition time needed to obtain acceptable water-suppressed spectra. The actual brain temperature of six pigs was monitored by fiber optic probes and by MRSI with high spatial and reduced spectral resolution. The temperature coefficient of brain water chemical shift was measured without internal spectral reference. Our results indicate that the proposed MRSI method can be used for monitoring the brain temperature changes during controlled hypothermia.