Evaluation of a new quantitative BOLD approach to map local blood oxygen saturation in healthy rat
نویسندگان
چکیده
Introduction Quantitative BOLD (Blood Oxygen Level Dependent) has been proposed to map brain oxygenation levels using MRI [1]. This approach yields tissular SO2 (oxygen saturation) estimates, i.e. a mean SO2 across the microvascular network in the MRI voxel. To improve the accuracy and the spatial resolution of SO2MR maps, an approach which combines a steady-state Blood Volume fraction (BVf) measurement scheme, B0 and T2 mapping techniques, and a simpler mathematical model has recently been proposed [2]. In this study, we evaluate the proposed acquisition scheme in healthy rats while varying the inspired oxygen fraction and using a complete physiological monitoring.
منابع مشابه
Is T2* enough to assess oxygenation? Quantitative blood oxygen level-dependent analysis in brain tumor.
PURPOSE To analyze the contribution of the transverse relaxation parameter (T2), macroscopic field inhomogeneities (B0), and blood volume fraction (BVf) to blood oxygen level-dependent (BOLD)-based magnetic resonance (MR) measurements of blood oxygen saturation (SO2) obtained in a brain tumor model. MATERIALS AND METHODS This study was approved by the local committee for animal care and use. ...
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