Hansen Kristoffer Lindskov, Møller-Sørensen Hasse, Kjaergaard Jesper, Jensen Maiken Brit, Lund Jens Teglgaard, Pedersen Mads Møller, Olesen Jacob Bjerring, Jensen Jørgen Arendt, Nielsen Michael Bachmann
1 Department of Radiology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.
2 Department of Cardiothoracic Anesthesiology, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.
Ultrason Imaging. 2017 Jan;39(1):3-18. doi: 10.1177/0161734615620137. Epub 2016 Aug 2.
Transverse oscillation (TO) is a real-time ultrasound vector flow method implemented on a commercial scanner. The TO setup was examined on a flowrig with constant and pulsatile flow. Subsequently, 25 patients undergoing cardiac bypass surgery were scanned intraoperatively with TO on the ascending aorta and compared to transesophageal echocardiography (TEE) and pulmonary artery catheter thermodilution (PACTD). On the flowrig, TO had a precision of 5.5%, 9.4% and 14.7%, a percentage error of 18.2%, 14.6% and 40.7%, and a mean bias of 0.4 cm/s, 36.8 ml/min and 32.4 ml/min for velocity and flow rate (constant and pulsatile) estimation. The correlation coefficients for all flowrig evaluations were 0.99 indicating systematic bias. After bias correction, the percentage error was reduced to 11.5%, 12.6% and 15.9% for velocity and flow rate (constant and pulsatile) estimation. In the in vivo setup, TO, TEE, and PACTD had a precision of 21.9%, 13.7%, and 12.0%. TO compared with TEE and PACTD had a mean bias of 12.6 cm/s and -0.08 l/min, and a percentage error of 23.4%, and 36.7%, respectively. The percentage error was reduced to 22.9% for the TEE comparison, but increased to 43.8% for the PACTD comparison, after correction for the systematic bias found in the flowrig. TO is a reliable and precise method for velocity and flow rate estimation on a flowrig. However, TO with the present setup, is not interchangeable with PACTD for cardiac volume flow estimation, but is a reliable and precise angle-independent ultrasound alternative for velocity estimation of cardiac flow.
横向振荡（TO）是一种在商用扫描仪上实现的实时超声矢量血流方法。在具有恒定和搏动血流的血流模拟装置上对TO设置进行了检查。随后，对25例接受心脏搭桥手术的患者在升主动脉上进行术中TO扫描，并与经食管超声心动图（TEE）和肺动脉导管热稀释法（PACTD）进行比较。在血流模拟装置上，对于速度和流量（恒定和搏动）估计，TO的精度分别为5.5%、9.4%和14.7%，百分比误差分别为18.2%、14.6%和40.7%，平均偏差分别为0.4 cm/s、36.8 ml/min和32.4 ml/min。所有血流模拟装置评估的相关系数均为0.99，表明存在系统偏差。经过偏差校正后，对于速度和流量（恒定和搏动）估计，百分比误差分别降至11.5%、12.6%和15.9%。在体内设置中，TO、TEE和PACTD的精度分别为21.9%、13.7%和12.0%。与TEE和PACTD相比，TO的平均偏差分别为12.6 cm/s和 -0.08 l/min，百分比误差分别为23.4%和36.7%。在对血流模拟装置中发现的系统偏差进行校正后，与TEE比较的百分比误差降至22.9%，但与PACTD比较的百分比误差增至43.8%。TO是一种在血流模拟装置上进行速度和流量估计的可靠且精确的方法。然而，采用当前设置的TO在心脏容积流量估计方面不能与PACTD互换，但它是一种可靠且精确的、与角度无关的超声方法，可用于心脏血流速度估计。
