Forbes K P, Pipe J G, Bird C R, Heiserman J E
Division of Neuroradiology, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, 350 West Thomas Road, Phoenix, AZ 85013, USA.
J Magn Reson Imaging. 2001 Sep;14(3):215-22. doi: 10.1002/jmri.1176.
While head motion is considered a significant problem in magnetic resonance imaging (MRI), there is no data to quantify its extent, severity, or effect on image quality. PROPELLER (Periodically Rotated Overlapping ParallEL Lines with Enhanced Reconstruction) MRI offers a novel means of quantifying and compensating for head motion. We performed axial T2-weighted PROPELLER (motion corrected: P-CR; uncorrected: P-UNCR) and conventional MRI (CONV), with equal scan times, in five normal volunteers and 35 clinical subjects. Volunteers were examined lying still and performing two separate head movements (shake "no" and nod "yes") to assess detection and compensation of in-plane motion by PROPELLER MRI. Images were examined by three radiologists for motion artifact and for overall image quality. Head rotation and translation was detected in all subjects during each slice acquisition, with expected changes occurring with volunteer head motion. Motion artifact was less commonly seen on PROPELLER than CONV MR (chi(2) test P < 0.001). PROPELLER was preferred over CONV in all subjects (P < 0.05) and P-CR was judged superior to P-UNCR (P = 0.02). Intracranial pathology was equally or better demonstrated with PROPELLER. PROPELLER MRI offers a means of quantifying head motion, reducing motion artifact, and improving image quality.
虽然头部运动在磁共振成像（MRI）中被认为是一个重大问题，但尚无数据来量化其程度、严重程度或对图像质量的影响。螺旋桨式（Periodically Rotated Overlapping ParallEL Lines with Enhanced Reconstruction，周期性旋转重叠平行线并增强重建）MRI提供了一种量化和补偿头部运动的新方法。我们对5名正常志愿者和35名临床受试者进行了轴向T2加权螺旋桨式MRI（运动校正：P-CR；未校正：P-UNCR）和传统MRI（CONV），扫描时间相同。对志愿者进行了静卧检查，并让他们进行两种不同的头部运动（摇头“不”和点头“是”），以评估螺旋桨式MRI对平面内运动的检测和补偿能力。三名放射科医生对图像进行了运动伪影和整体图像质量检查。在每个层面采集过程中，所有受试者均检测到头部旋转和平移，志愿者头部运动时出现了预期的变化。螺旋桨式MRI上运动伪影比传统MRI少见（卡方检验P<0.001）。在所有受试者中，螺旋桨式MRI比传统MRI更受青睐（P<0.05），且P-CR被判定优于P-UNCR（P = 0.02）。螺旋桨式MRI对颅内病变的显示效果相同或更好。螺旋桨式MRI提供了一种量化头部运动、减少运动伪影和提高图像质量的方法。
