Yoshitaka Bito1, Yuko Kawai2, Koji Hirata1, Toshihiko Ebisu3, Yosuke Otake1, Satoshi Hirata1, Toru Shirai1, Yoshihisa Soutome1, Hisaaki Ochi1, Masahiro Umed
1Central Research Laboratory, Hitachi, Ltd., Kokubunji-shi, Tokyo, Japan; 2Medical Informatics, Meiji University of Integrative Medicine, Kyoto, Japan; 3Neurosurgery, Nantan General Hospital, Kyoto, Japan; 4Neurosurgery, Meiji University of Integrative Medicine, Kyoto, Japan
Diffusion-weighted echo-planar spectroscopic imaging with a pair of bipolar diffusion gradients (DW-EPSI with BPGs) was used to acquire changes in apparent diffusion coefficient (ADC) for multiple metabolites, namely, N-acetylaspartate (NAA), creatine (Cr) and choline (Cho), in rat brains after a right middle cerebral artery occlusion (MCAO). The acquired changes in ADC maps of the metabolites and water were analyzed by using Gaussian mixture distribution, which takes advantage of the multiple spatial pixels acquired simultaneously by diffusion-weighted spectroscopic imaging. It is shown that DW-EPSI with BPGs is effective for investigating spatially varying ADC changes for metabolites and that this technique may be useful for understanding intra-cellular dynamics by using multiple metabolites as probes.