Translational Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada.
Graduate Department of Exercise Sciences, University of Toronto, Toronto, Ontario, Canada.
Physiol Rep. 2022 May;10(10):e15182. doi: 10.14814/phy2.15182.
Magnetic Resonance Imaging (MRI) is well-suited for imaging peripheral blood flow due to its non-invasive nature and excellent spatial resolution. Although MRI is routinely used in adults to assess physiological changes in chronic diseases, there are currently no MRI-based data quantifying arterial flow in pediatric or adolescent populations during exercise. Therefore the current research sought to document femoral arterial blood flow at rest and following exercise in a pediatric-adolescent population using phase contrast MRI, and to present test-retest reliability data for this method. Ten healthy children and adolescents (4 male; mean age 14.8 ± 2.4 years) completed bloodwork and resting and exercise MRI. Baseline images consisted of PC-MRI of the femoral artery at rest and following a 5 × 30 s of in-magnet exercise. To evaluate test-retest reliability, five participants returned for repeat testing. All participants successfully completed exercise testing in the MRI. Baseline flow demonstrated excellent reliability (ICC = 0.93, p = 0.006), and peak exercise and delta rest-peak flow demonstrated good reliability (peak exercise ICC = 0.89, p = 0.002, delta rest-peak ICC = 0.87, p = 0.003) between-visits. All three flow measurements demonstrated excellent reliability when assessed with coefficients of variance (CV's) (rest: CV = 6.2%; peak exercise: CV = 7.3%; delta rest-peak: CV = 7.1%). The mean bias was small for femoral arterial flow. There was no significant mean bias between femoral artery flow visits 1 and 2 at peak exercise. There were no correlations between age or height and any of the flow measurements. There were no significant differences between male and female participants for any of the flow measurements. The current study determined that peripheral arterial blood flow in children and adolescents can be evaluated using non-invasive phase contrast MRI. The MRI-based techniques that were used in the current study for measuring arterial flow in pediatric and adolescent patients demonstrated acceptable test-retest reliability both at rest and immediately post-exercise.
磁共振成像（MRI）因其非侵入性和出色的空间分辨率，非常适合用于成像外周血流。尽管 MRI 在成人中通常用于评估慢性病的生理变化，但目前尚无基于 MRI 的数据可量化儿童或青少年在运动期间的动脉血流量。因此，目前的研究旨在使用相位对比 MRI 记录儿科青少年人群在休息和运动后的股动脉血流，并提供该方法的测试 - 重测可靠性数据。10 名健康的儿童和青少年（4 名男性；平均年龄 14.8±2.4 岁）完成了血液检查和休息及运动 MRI。基线图像包括休息时和在磁体内进行 5×30 秒运动后的股动脉 PC-MRI。为了评估测试 - 重测可靠性，有 5 名参与者返回进行重复测试。所有参与者都成功地在 MRI 中完成了运动测试。基线流量具有极好的可靠性（ICC=0.93，p=0.006），峰值运动和休息 - 峰值流量的增量显示出良好的可靠性（峰值运动 ICC=0.89，p=0.002，休息 - 峰值 ICC=0.87，p=0.003）。在两次就诊之间，所有三种流量测量的变异系数（CV）均表现出极好的可靠性（休息时：CV=6.2%；峰值运动时：CV=7.3%；休息 - 峰值增量：CV=7.1%）。股动脉流量的平均偏差很小。在峰值运动时，股动脉流量的两次就诊之间没有显著的平均偏差。年龄或身高与任何流量测量均无相关性。男性和女性参与者之间的任何流量测量均无显著差异。本研究确定，儿童和青少年的外周动脉血流可以使用非侵入性的相位对比 MRI 进行评估。本研究中用于测量儿科和青少年患者动脉血流的基于 MRI 的技术在休息和运动后即刻均表现出可接受的测试 - 重测可靠性。
