Knight Silvin Paul, Browne Jacinta Elizabeth, Meaney James Frances Mary, Fagan Andrew John
School of Medicine, Trinity College University of Dublin / National Centre for Advanced Medical Imaging (CAMI), St James's Hospital, Dublin 8, Ireland.
School of Physics and Medical Ultrasound Physics and Technology Group, Centre of Industrial Engineering Optics, FOCAS, Dublin Institute of Technology, Dublin 8, Ireland.
MAGMA. 2017 Oct;30(5):461-471. doi: 10.1007/s10334-017-0619-y. Epub 2017 Apr 10.
The aim of this study was to investigate the effect of the temporal resolution (T ) and acquisition duration (AD) on the measurement accuracy of contrast concentration-time curves (CTCs), and derived phenomenological and pharmacokinetic parameter values, in a dynamic contrast-enhanced MRI experiment using a novel phantom test device.
'Ground truth' CTCs were established using a highly precise optical imaging system. These precisely known CTCs were produced in an anthropomorphic environment, which mimicked the male pelvic region, and presented to the MRI scanner for measurement. The T was varied in the range [2-24.4 s] and the AD in the range [30-600 s], and the effects on the measurement accuracy were quantified.
For wash-in parameter measurements, large underestimation errors (up to 40%) were found using T values ≥16.3 s; however, the measured wash-out rate did not vary greatly across all T values tested. Errors in derived K and v values were below 14 and 12% for acquisitions with {T ≤ 8.1 s, AD ≥ 360 s} and {T ≤ 16.3 s, AD ≥ 360 s}, respectively, but increased dramatically outside these ranges.
Errors in measured wash-in, wash-out, K , and v parameters were minimised using T ≤ 8.1 s and AD ≥ 360 s, with large errors recorded outside of this range.
本研究旨在通过使用一种新型体模测试设备的动态对比增强磁共振成像实验，研究时间分辨率（T）和采集持续时间（AD）对对比剂浓度-时间曲线（CTCs）测量准确性以及衍生的现象学和药代动力学参数值的影响。
使用高精度光学成像系统建立“真实”CTCs。这些精确已知的CTCs在模拟男性盆腔区域的人体环境中生成，并呈现给MRI扫描仪进行测量。T在[2 - 24.4秒]范围内变化，AD在[30 - 600秒]范围内变化，并对测量准确性的影响进行量化。
对于注入参数测量，使用T值≥16.3秒时发现存在较大的低估误差（高达40%）；然而，在所有测试的T值范围内，测得的洗脱率变化不大。对于{T≤8.1秒，AD≥360秒}和{T≤16.3秒，AD≥360秒}的采集，衍生的K和v值的误差分别低于14%和12%，但在这些范围之外误差急剧增加。
使用T≤8.1秒和AD≥360秒时，测得的注入、洗脱、K和v参数的误差最小，在此范围之外记录到较大误差。
