White R D, Paschal C B, Clampitt M E, Spraggins T A, Lenz G W
Department of Radiology, Cleveland Clinic Foundation, OH 44195.
J Magn Reson Imaging. 1991 May-Jun;1(3):347-55. doi: 10.1002/jmri.1880010313.
A new electrocardiograph (ECG)-independent, "wireless" gating technique for cine magnetic resonance (MR) imaging was evaluated in 23 cases of cardiovascular disease; in each case, standard ECG-dependent image loops were available for comparison. The ECG-independent strategy references cine MR imaging data retrospectively to inherent periodic changes in MR signal related to the cardiac cycle. With a "double-section" method, both timing data reflecting such changes and imaging data can be acquired simultaneously. "Artificial R waves" are extracted from the timing data acquired with a projection approach. The ECG-independent image loops were diagnostic in 91% of cases. Their overall image quality was at least equal to that of available ECG-dependent versions in only 39% of cases, but this proportion increased to 53% if cases with suboptimal imaging orientations for monitoring of the motion-dependent signal changes were excluded. Orientation appeared to be the primary technical limitation associated with this ECG-independent technique; however, poor ventricular function also significantly impaired performance. Improvement in the performance of the ECG-independent strategy is anticipated with technical advances.
一种用于电影磁共振（MR）成像的新型独立于心电图（ECG）的“无线”门控技术在23例心血管疾病患者中进行了评估；每例患者均有标准的依赖ECG的图像环可供比较。这种独立于ECG的策略通过回顾性地将电影MR成像数据与心脏周期相关的MR信号固有周期性变化进行关联。采用“双截面”方法，可以同时获取反映此类变化的定时数据和成像数据。通过投影方法获取的定时数据中提取“人工R波”。独立于ECG的图像环在91%的病例中具有诊断价值。其整体图像质量仅在39%的病例中至少与可用的依赖ECG的版本相当，但如果排除监测与运动相关信号变化时成像方向欠佳的病例，这一比例将增至53%。成像方向似乎是与这种独立于ECG的技术相关的主要技术限制；然而，心室功能不佳也会显著影响其性能。随着技术进步，预计独立于ECG的策略性能将得到改善。
