为了更好地利用相位信息补偿血流造成的影响，本文对磁敏感加权成像（SWI）中存在的相位缠绕问题展开了研究。为提高解缠绕的准确性，本文提出了幅度图像引导的磁敏感加权图像相位解缠算法。基本思路如下：① 通过改进旋转不变非局部主成分分析滤波（PRI-NL-PCA）降低噪声影响；② 结合 C-V 模型水平集提取相位图像中对应的实性组织区域，从而规避背景噪声对相位解缠方法的影响；③ 采用相位补偿的方法约束 K 空间重建出的相位图像。最后，利用四种统计量作为量化指标，评价解缠绕方法的可靠性：相位误差的突变点个数、均值（M）、方差（Var），以及阳性百分比（Pos）和阴性百分比（Neg）。通过对比仿真数据和 226 组真实头部磁敏感数据，结果表明，本文算法相对于经典的枝切法和最小二乘法，解缠绕结果具有较高的准确性
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