Rastegar Jooybari Fatemeh, Huynh Christopher, Portnoy Sharon, Voutsas Jonathan, Balmer-Minnes Diana, Saprungruang Ankavipar, Yoo Shi-Joon, Lam Christopher Z, Macgowan Christopher K
University of Toronto, 27 King's College Cir, Toronto, ON, M5S 1A1, Canada.
Hospital for Sick Children, Toronto, Canada.
Pediatr Radiol. 2025 May;55(6):1223-1234. doi: 10.1007/s00247-025-06226-1. Epub 2025 Apr 5.
Conventional four-dimensional (4D) flow magnetic resonance imaging (MRI) is limited by long scan times, particularly in pediatric congenital heart disease (CHD) patients.
This study evaluates accelerated 4D flow MRI incorporating respiratory compensation and cardiac view sharing in healthy adults and pediatric CHD patients.
Subjects underwent 5-min free-breathing protocol with a three-dimensional (3D) radial trajectory and compressed sensing reconstruction. The 4D flow MRI reconstruction pipeline was improved by respiratory soft-gating and cardiac view sharing. Flow in major thoracic vessels was compared with two-dimensional (2D) phase contrast MRI, the reference standard.
Fourteen pediatric CHD patients (median age: 13 years (interquartile range (IQR): 5)) and four healthy adult volunteers (median age: 26 years (IQR: 3)) were recruited. Soft-gating improved diaphragm sharpness and reduced respiratory-induced blur (image quality scores: healthy: 46.1 soft-gated vs. 47.2 non-gated; CHD: 47.8 soft-gated vs. 48.2 non-gated). View sharing reduced undersampling artifacts and enhanced the signal-to-noise ratio (SNR, healthy: +9.9%; CHD: +3.8%). In healthy adults, correlations with 2D phase contrast MRI were strong for mean flow (R=0.94, slope=0.94±0.12, root mean square error (RMSE)=6.4 ml/s; bias=1.1±6.4 ml/s, P=0.45) and peak flow (R=0.9, slope=0.86±0.13, RMSE=40.9 ml/s; bias=21.3±44.7 ml/s, P=0.04). Similarly, CHD patients showed a strong correlation for mean flow (R=0.88, slope=0.93±0.09, RMSE=8.3 ml/s) and peak flow (R=0.97, slope=0.98±0.03, RMSE=25.9 ml/s). Internal consistency for 4D flow MRI in CHD cases showed mean percent differences of 6.1% Main pulmonary artery=Left pulmonary artery+Right pulmonary artery and 6.5% Ascending aorta=Descending aorta+Superior vena cava.
The accelerated 4D flow MRI method provides robust flow quantification and visualization in pediatric CHD patients, strongly correlating with 2D phase contrast MRI and completing scans in 5 min for clinical use.
传统的四维（4D）流动磁共振成像（MRI）受限于较长的扫描时间，尤其是在小儿先天性心脏病（CHD）患者中。
本研究评估了在健康成人和小儿CHD患者中结合呼吸补偿和心脏视图共享的加速4D流动MRI。
受试者采用三维（3D）径向轨迹和压缩感知重建进行5分钟自由呼吸协议扫描。通过呼吸软门控和心脏视图共享改进了4D流动MRI重建流程。将主要胸段血管中的血流与二维（2D）相位对比MRI（参考标准）进行比较。
招募了14名小儿CHD患者（中位年龄：13岁（四分位间距（IQR）：5））和4名健康成人志愿者（中位年龄：26岁（IQR：3））。软门控提高了膈肌清晰度并减少了呼吸引起的模糊（图像质量评分：健康者：软门控为46.1，非门控为47.2；CHD患者：软门控为47.8，非门控为48.2）。视图共享减少了欠采样伪影并提高了信噪比（SNR，健康者：+9.9%；CHD患者：+3.8%）。在健康成人中，与2D相位对比MRI的相关性在平均血流方面很强（R = 0.94，斜率 = 0.94±0.12，均方根误差（RMSE）= 6.4 ml/s；偏差 = 1.1±6.4 ml/s，P = 0.45），在峰值血流方面也很强（R = 0.9，斜率 = 0.86±0.13，RMSE = 40.9 ml/s；偏差 = 21.3±44.7 ml/s，P = 0.04）。同样，CHD患者在平均血流方面显示出很强的相关性（R = 0.88，斜率 = 0.93±0.09，RMSE = 8.3 ml/s），在峰值血流方面也很强（R = 0.97，斜率 = 0.98±0.03，RMSE = 25.9 ml/s）。CHD病例中4D流动MRI的内部一致性显示，主肺动脉=左肺动脉+右肺动脉的平均百分比差异为6.1%，升主动脉=降主动脉+上腔静脉的平均百分比差异为6.5%。
加速4D流动MRI方法在小儿CHD患者中提供了可靠的血流定量和可视化，与2D相位对比MRI有很强的相关性，且5分钟即可完成扫描以供临床使用。
