Kalden P, Kreitner K F, Voigtländer T, Roberts H, Roberts T, Krummenauer F, Becker D, Wittlinger T, Meyer J, Thelen M
Klinik und Poliklinik für Radiologie, Johannes-Gutenberg-Universität Mainz.
Rofo. 1998 Oct;169(4):378-82. doi: 10.1055/s-2007-1015303.
Comparison of a breath-hold, velocity-encoded, phase-difference magnetic resonance (MR) sequence for intracardiac shunt flow measurement with the invasive shunt size determination by oximetry.
10 patients with different cardiac shunts (6 ASD/3 VSD/1 PDA) and four healthy individuals were investigated using a 1.5 Tesla Siemens Vision system. For flow measurements a breath-hold, velocity-encoded, phase-difference magnetic resonance (MR) sequence was used ('through plane', FLASH 2D-sequence, TR/TE 110/5 ms, 'velocity encoding' 250 cm/s). Mean flow (ml/R-R interval) in the ascending aorta, the pulmonary trunk, and the right and left pulmonary arteries was determined. The ratio of the mean flow in the pulmonary circulation (Qp: sum of the mean flows in the right and left pulmonary arteries) and the systemic circulation (Qs: mean flow in the proximal aorta) was compared with the Qp/Qs ratios determined by the invasive oxymetric technique. Oximetry was performed within 24 hours after MR imaging.
In the 4 healthy individuals MR flow measurement yielded a Qp/Qs ratio of 0.96 +/- 0.15. In the 10 patients with the various shunt defects, the non-invasive shunt determination by MR gave a Qp/Qs ratio of 2.09 +/- 0.67. The percentage of the calculated shunt sizes was 47.05 +/- 17.45%. In the comparison with the results determined by the invasive oxymetric technique, the MR data showed a strong correlation of r = 0.87.
Breath-hold, velocity-encoded, phase-difference MR-technique enables a reliable quantification of cardiac shunts within a short acquisition time.
比较屏气、速度编码、相位差磁共振（MR）序列用于心内分流流量测量与通过血氧测定法进行的有创分流大小测定。
使用1.5特斯拉西门子Vision系统对10例患有不同心脏分流（6例房间隔缺损/3例室间隔缺损/1例动脉导管未闭）的患者和4名健康个体进行研究。对于流量测量，采用屏气、速度编码、相位差磁共振（MR）序列（“层面内”，FLASH 2D序列，TR/TE 110/5毫秒，“速度编码”250厘米/秒）。测定升主动脉、肺动脉主干以及左右肺动脉的平均流量（毫升/R-R间期）。将肺循环（Qp：左右肺动脉平均流量之和）与体循环（Qs：主动脉近端平均流量）中的平均流量比值与通过有创血氧测定技术测定的Qp/Qs比值进行比较。在MR成像后24小时内进行血氧测定。
在4名健康个体中，MR流量测量得出的Qp/Qs比值为0.96±0.15。在10例患有各种分流缺陷的患者中，通过MR进行的无创分流测定得出的Qp/Qs比值为2.09±0.67。计算得出的分流大小百分比为47.05±17.45%。与有创血氧测定技术测定的结果相比，MR数据显示出r = 0.87的强相关性。
屏气、速度编码、相位差MR技术能够在短采集时间内可靠地定量心内分流。
