Huang Teng-Yi, Tseng Yu-Shen, Tang Yu-Wei, Lin Yi-Ru
Department of Electrical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan 106, Republic of China.
Med Phys. 2012 Aug;39(8):4896-902. doi: 10.1118/1.4736977.
Clinical cardiac MR imaging techniques generally require patients to hold their breath during the scanning process to minimize respiratory motion-related artifacts. However, some patients cannot hold their breath because of illness or limited breath-hold capacity. This study aims to optimize the PROPELLER reconstruction for free-breathing myocardial T1-weighted imaging.
Eight healthy volunteers (8 men; mean age 26.4 years) participated in this study after providing institutionally approved consent. The PROPELLER encoding method can reconstruct a low-resolution image from every blade because of k-space center oversampling. This study investigated the feasibility of extracting a respiratory trace from the PROPELLER blades by implementing a fully automatic region of interest selection and introducing a best template index to account for the property of the human respiration cycle.
Results demonstrated that the proposed algorithm significantly improves the contrast-to-noise ratio and the image sharpness (p < 0.05).
The PROPELLER method is expected to provide a robust tool for clinical application in free-breathing myocardial T1-weighted imaging. It could greatly facilitate the acquisition procedures during such a routine examination.
临床心脏磁共振成像技术通常要求患者在扫描过程中屏气,以尽量减少与呼吸运动相关的伪影。然而,一些患者由于疾病或屏气能力有限而无法屏气。本研究旨在优化自由呼吸心肌T1加权成像的螺旋桨重建。
8名健康志愿者(8名男性;平均年龄26.4岁)在获得机构批准的同意后参与了本研究。由于k空间中心过采样,螺旋桨编码方法可以从每个叶片重建低分辨率图像。本研究通过实施全自动感兴趣区域选择并引入最佳模板指数以考虑人类呼吸周期的特性,研究了从螺旋桨叶片中提取呼吸轨迹的可行性。
结果表明,所提出的算法显著提高了对比度噪声比和图像清晰度(p < 0.05)。
螺旋桨方法有望为自由呼吸心肌T1加权成像的临床应用提供一个强大的工具。它可以极大地便利这种常规检查期间的采集程序。