| Resumo: |
Objective: Application of high-field 4.23 T MRI clinical imager was demonstrated for sodium-magnetic resonance imaging (MRI) data acquisition. Primary hypothesis: Sodium [Na] in brain is MR visible. Secondary hypothesis was, if, application of multislice spin echo (MSSE) pulse sequence at selected scan parameters can sufficiently visualize the total sodium signal as indicator of sub-clinical activity. Material and Methods: MSSE pulse sequence technique was used to simulate sodium images of human brain. For validation purpose, inversion recovery pulse sequence was validated by optimization of scan inversion time (TI). Phantom of sodium and rat brain were imaged. Sodium images were validated and compared with proton MRI images. Results: MSSE pulse technique enabled to visualize the sodium signal at optimized scan parameters. Specifically, MSSE pulse technique enabled the identification of different sodium rich areas due to their subphysiological activity in the brain, comparable with proton MRI images. Reconstruction images of brain further enhanced the power to classify the brain tissue. Intracellular sodium images of agarose-saline solution filled-tube phantom were generated by use of inversion recovery pulse sequence. Conclusion: Using MSSE pulse sequence at 4.23 T, in vivo sodium images can be generated within acceptable scan time for routine clinical brain examination for achieving better sub-physiological information as obtained from proton MRI.
|
