CAJ | 학술논문

定量磁化率成像(QSM)利用一般成像技术舍弃的相位信息得到局部磁场变化特性，通过复杂的场到源反演计算，可直接得到定量的磁化率图，它广泛应用于测量血氧饱和度、脑部微出血、铁沉积、组织钙化等方面。然而，梯度磁场中流动会引起相位错误，并且产生显著的流动伪影，最终得到错误的QSM图像。为了矫正流动的影响，该文在3 T磁共振系统上实现了三维多回波流动补偿梯度回波序列，并用该序列采集流动水模和志愿者颅脑数据。流动水模和颅脑数据均显示，流动补偿能够明显矫正相位错误，消除流动伪影。颅脑横断位QSM结果证明，流动补偿序列可以消除血液流动引起的QSM的错误，提高QSM的准确性。
정량자화솔성상(QSM)이용일반성상기술사기적상위신식득도국부자장변화특성，통과복잡적장도원반연계산，가직접득도정량적자화솔도，타엄범응용우측량혈양포화도、뇌부미출혈、철침적、조직개화등방면。연이，제도자장중류동회인기상위착오，병차산생현저적류동위영，최종득도착오적QSM도상。위료교정류동적영향，해문재3 T자공진계통상실현료삼유다회파류동보상제도회파서렬，병용해서렬채집류동수모화지원자로뇌수거。류동수모화로뇌수거균현시，류동보상능구명현교정상위착오，소제류동위영。로뇌횡단위QSM결과증명，류동보상서렬가이소제혈액류동인기적QSM적착오，제고QSM적준학성。
Venous blood oxygen saturation, cerebral microbleeds, iron deposition and tissue calcification can be measured by quantitative susceptibility mapping (QSM) via deconvolving the magnetic resonance (MR) phase signal. However, accurate estimation of phase signal and magnitude image in QSM may be affected by flow-induced errors in the presence of field gradient, which would ultimately lead to errors in the quantitative susceptibility map reconstructed. The aim of this study is to develop a method for correcting the flow-induced errors in phase signal and magnitude image in QSM. Flow-compensated data acquisition was achieved using a three-dimensional full flow compensated multi-echo gradient echo sequence. Phantom andin vivo experiments were carried out to validate the method proposed. The results of these experiments demonstrated that flow compensation can reduce errors in the phase signal and magnitude images. Improved quantitative susceptibility map of the superior sagittal sinus vein in human brain could be obtained with the proposed method.