3D Multi-echo Flow Compensated Quantitative Susceptibility Mapping In MRI

Quantitative susceptibility imaging (QSM) can be obtained by deconvolving the MR phase signal which was abandoned in most general imaging technology, a complex method was carried out for field to the source inversion calculation, so quantitative susceptibility map can be obtained directly. However blood flow could influence phase information where the gradient magnetic field existed, and produced significant flow artifact, eventually leaded to an error QSM. Our research applied flow compensation gradient for optimizing the sequence and improving the accuracy of phase information acquisition, in order to improve the accuracy and reliability of QSM.In order to correct the flow influence, phantom test was carried out during first stage. We designed a flow phantom based on human blood flow information and use this phantom linked together with a pump to simulate human blood characteristics for simulation experiments, and lastly get the reliable conclusions to lay the foundation for further experiments; Secondly, a 3D full flow compensated multi-echo gradient echo sequence was be obtained from Siemens IDEA platform, after the successful of the test run to check the data parameter and test the sequence on Siemens 3T MRI scanner to obtain a reliable result. Finally, phantom and in vivo experiments were carried out for acquisition and analyze the data processing.The phantom and in vivo human experiments demonstrated reduced error in phase signal and magnitude images with flow compensation. In vivo human experiment also demonstrated improvements in the quantitative susceptibility map of the superior sagittal sinus vein. Flow compensation gradient could significantly eliminate flow artifact and correct the phase-error to improving the accuracy and reliability of the QSM finally.