Detailed imaging of cerebral glucose metabolism for dementia diagnosis including omission of arterial blood sampling and correction of partial volume effect

基于map的脑糖代谢估计算法能够归档，比普通似然方法具有更好的脑糖代谢成像性能。该算法避免了迭代计算和寻找最优点，避免了对初始值的依赖和不收敛。正常人和阿尔茨海默病患者的结果与基于roi的分析相吻合，计算只需30分钟。建立了一种基于独立分量分析的遗漏动脉血采集新算法，利用这两种算法，在较短的测量时间内实现了无需动脉血采集的葡萄糖代谢成像的实用方案。针对部分体积效应（PVE）的校正问题，提出了一种基于统计建模和形态学运算的修正算法。该算法首先根据体素值将MRI图像分割为若干解剖结构，然后应用形态学操作将脑解剖结构的三维结构融合。最后，假设白质和灰质区域体素值相同，使用线性估计对PVE进行补偿。将PVE算法应用于外周苯二氮卓类受体配体PK11195的PET数据，可以很好地校正PVE。

MAP-based estimation algorithm could be archived which had better performance than ordinary likelihood approach for imaging of cerebral glucose metabolism. This algorithm could avoid an iterative computation and searching an optimal points, therefore it was free from dependency to an initial value and misconvergence. The results from normal and Alzheimer cases were coincided with ROI-based analysis, and the computation required only 30 minutes.Also, a new algorithm for omission arterial blood sampling based on independent component analysis was established, and using the both algorithm, the practical scheme for glucose metabolism imaging without arterial blood sampling was realized in a shorter measurement duration than usual.On a correction of partial volume effect (PVE), a algorithm using a statistical modeling and morphological operation was developed. The algorithm first segmented a MRI image to some anatomical structures based on voxel values, then a morphological operations were applied to incorporate three-dimensional structure of brain anatomy. Finally, PVE was compensated using a linear estimation assuming regional voxel values in white matter and gray matter were common. When the PVE algorithm was applied to PET data of PK11195, a ligand for peripheral benzodiazepine receptors, PVE could be corrected well.