Development of next-generation MRI technology for microstructure tomography

In this study, we applied a high-precision analysis method of NHA to MRI. In experiment, we placed multi objects in micro space, and MRI measurement data assuming the ideal environment was created by computer simulation. The created MRI measurement data is analyzed by each method; FFT commonly used for MRI image reconstruction, interpolation method, NHA. MRI images were reconstructed and compared based on the analysis results of each method. From the experimental results, in the MRI image by FFT and interpolation method, the resolution was insufficient, and due to side lobe interference, it has not been possible to separate and represent a multi objects. On the other hand, in the MRI image by NHA, the occurrence of side lobes was greatly suppressed by accurately analyzing the measurement data, and NHA can visualized space of less than 100 μm. From above results, there is possibility of ultra-high resolution MRI using NHA.

MRIは、仮想的に断層撮影を行うために、内部で主に２次元FFTを用いて画像を再構成している。このFFTに代わって、２次元NHAを応用することで、既存のハードウェアの性能を極限まで高め、低磁場でこれまで以上の空間分解能を実現できる可能性を示した。