Cardiovascular Magnetic Resonance Unit, National Heart and Lung Institute, Imperial College, London.
Magn Reson Imaging. 2011 May;29(4):568-78. doi: 10.1016/j.mri.2010.11.004. Epub 2011 Feb 2.
This study quantitatively assesses the effectiveness of retrospective beat-to-beat respiratory motion correction (B2B-RMC) at near 100% efficiency using high-resolution coronary artery imaging. Three-dimensional (3D) spiral images were obtained in a coronary respiratory motion phantom with B2B-RMC and navigator gating. In vivo, targeted 3D coronary imaging was performed in 10 healthy subjects using B2B-RMC spiral and navigator gated balanced steady-state free-precession (nav-bSSFP) techniques. Vessel diameter and sharpness in proximal and mid arteries were used as a measure of respiratory motion compensation effectiveness and compared between techniques. Phantom acquisitions with B2B-RMC were sharper than those acquired with navigator gating (B2B-RMC vs. navigator gating: 1.01±0.02 mm(-1) vs. 0.86±0.08 mm(-1), P<.05). In vivo B2B-RMC respiratory efficiency was significantly and substantially higher (99.7%±0.5%) than nav-bSSFP (44.0%±8.9%, P<.0001). Proximal and mid vessel sharpnesses were similar (B2B-RMC vs. nav-bSSFP, proximal: 1.00±0.14 mm(-1) vs. 1.08±0.11 mm(-1), mid: 1.01±0.11 mm(-1) vs. 1.05±0.12 mm(-1); both P=not significant [ns]). Mid vessel diameters were not significantly different (2.85±0.39 mm vs. 2.80±0.35 mm, P=ns), but proximal B2B-RMC diameters were slightly higher (2.85±0.38 mm vs. 2.70±0.34 mm, P<.05), possibly due to contrast differences. The respiratory efficiency of B2B-RMC is less variable and significantly higher than navigator gating. Phantom and in vivo vessel sharpness and diameter values suggest that respiratory motion compensation is equally effective.
本研究使用高分辨率冠状动脉成像技术，定量评估了近 100%效率的回顾性逐拍呼吸运动校正（B2B-RMC）的效果。在具有 B2B-RMC 和导航门控的冠状动脉呼吸运动体模中获得三维（3D）螺旋图像。在 10 名健康受试者中，使用 B2B-RMC 螺旋和导航门控平衡稳态自由进动（nav-bSSFP）技术进行靶向 3D 冠状动脉成像。近端和中段血管的血管直径和锐利度用作呼吸运动补偿效果的度量，并在技术之间进行比较。具有 B2B-RMC 的体模采集比具有导航门控的采集更清晰（B2B-RMC 与导航门控：1.01±0.02mm(-1)比 0.86±0.08mm(-1)，P<.05）。体内 B2B-RMC 呼吸效率显著且大大高于 nav-bSSFP（99.7%±0.5%比 44.0%±8.9%，P<.0001）。近端和中段血管锐利度相似（B2B-RMC 与 nav-bSSFP，近端：1.00±0.14mm(-1)比 1.08±0.11mm(-1)，中段：1.01±0.11mm(-1)比 1.05±0.12mm(-1)；两者 P=无显著差异[ns]）。中段血管直径无显著差异（2.85±0.39mm 比 2.80±0.35mm，P=ns），但近端 B2B-RMC 直径稍高（2.85±0.38mm 比 2.70±0.34mm，P<.05），可能是由于对比度差异所致。B2B-RMC 的呼吸效率变化较小，明显高于导航门控。体模和体内血管锐利度和直径值表明呼吸运动补偿同样有效。
