Jin Zhaoyang, Xia Ling, Zhang Minming, Du Yiping P
Department of Biomedical Engineering, Zhejiang University, Hangzhou 310027, China ; Key Laboratory for Biomedical Engineering of Education Ministry of China, Hangzhou, China ; College of Automation, Hangzhou Dianzi University, Hangzhou, China.
Department of Biomedical Engineering, Zhejiang University, Hangzhou 310027, China ; Key Laboratory for Biomedical Engineering of Education Ministry of China, Hangzhou, China.
Comput Math Methods Med. 2014;2014:812785. doi: 10.1155/2014/812785. Epub 2014 Jun 10.
Conventional susceptibility-weighted imaging (SWI) uses both phase and magnitude data for the enhancement of venous vasculature and, thus, is subject to signal loss in regions with severe field inhomogeneity and in the peripheral regions of the brain in the minimum-intensity projection. The purpose of this study is to enhance the visibility of the venous vasculature and reduce the artifacts in the venography by suppressing the background signal in postprocessing. A high-pass filter with an inverted Hamming window or an inverted Fermi window was applied to the Fourier domain of the magnitude images to enhance the visibility of the venous vasculature in the brain after data acquisition. The high-pass filtering approach has the advantages of enhancing the visibility of small veins, diminishing the off-resonance artifact, reducing signal loss in the peripheral regions of the brain in projection, and nearly completely suppressing the background signal. The proposed postprocessing technique is effective for the visualization of small venous vasculature using the magnitude data alone.
传统的磁敏感加权成像（SWI）利用相位和幅度数据来增强静脉血管的显示，因此，在磁场严重不均匀的区域以及最小强度投影中大脑的周边区域会出现信号丢失。本研究的目的是通过在后处理中抑制背景信号来提高静脉血管的可视性并减少静脉造影中的伪影。在数据采集后，将具有倒汉明窗或倒费米窗的高通滤波器应用于幅度图像的傅里叶域，以提高大脑中静脉血管的可视性。高通滤波方法具有增强小静脉可视性、减少失谐伪影、减少投影中大脑周边区域的信号丢失以及几乎完全抑制背景信号的优点。所提出的后处理技术仅使用幅度数据就能有效地显示小静脉血管。
