Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, The Netherlands.
CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands.
J Magn Reson Imaging. 2017 Oct;46(4):1053-1059. doi: 10.1002/jmri.25648. Epub 2017 Feb 2.
To assess parameter agreement of volume transfer coefficient (K ) between two vascular regions and to study the correlation with microvessel density on histology. The dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameter K is frequently used to study atherosclerotic plaque microvasculature. K has been reported using different descriptive statistics (mean, median, 75 percentile) either for the whole vessel wall or the adventitia in previous studies.
DCE-MRI parameter agreement was analyzed in 110 symptomatic patients with ≥2 mm carotid plaque that underwent a 3T carotid DCE-MRI examination. K was estimated in the entire vessel wall and adventitia. Twenty-three patients underwent carotid endarterectomy and were used for comparison with histological quantification of microvessel density of the plaque using CD31 immunohistochemistry. DCE-MRI parameters in the vessel wall regions were compared using Pearson's correlation coefficient, Bland-Altman analysis, and a two-sided paired samples t-test. Correlation of the DCE-MRI parameters with histology was studied using the Pearson's correlation coefficient.
Median adventitial K was 5% higher (P = 0.003) than entire vessel wall K , with no differences for other descriptive statistics. Vessel wall and adventitial K showed similar moderately strong correlations with plaque microvessel density on histology (Pearson's ρ: 0.59-0.65 [P < 0.003] and 0.52-0.64 [P < 0.011], respectively).
The similar moderately strong correlations for vessel wall and adventitial K with microvessel density on histology suggested that both regions reflected plaque microvessel density. Care should to be taken when comparing absolute values between studies. Future studies incorporating thresholds for risk stratification need to agree upon standardization of DCE-MRI parameters.
2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1053-1059.
评估两个血管区域之间容积转移系数（K）的参数一致性，并研究其与组织学微血管密度的相关性。动态对比增强磁共振成像（DCE-MRI）参数 K 常用于研究动脉粥样硬化斑块的微血管。在之前的研究中，K 已经使用不同的描述性统计数据（平均值、中位数、75 百分位数）进行了报道，这些数据要么是整个血管壁的，要么是外膜的。
对 110 例颈动脉斑块≥2mm 的症状性患者进行了 3T 颈动脉 DCE-MRI 检查，分析了 DCE-MRI 参数的一致性。在整个血管壁和外膜中估计了 K。23 例患者接受了颈动脉内膜切除术，并与 CD31 免疫组化法对斑块微血管密度的组织学定量进行了比较。使用 Pearson 相关系数、Bland-Altman 分析和双侧配对样本 t 检验比较血管壁区域的 DCE-MRI 参数。使用 Pearson 相关系数研究 DCE-MRI 参数与组织学的相关性。
外膜 K 的中位数比整个血管壁 K 高 5%（P=0.003），但其他描述性统计数据无差异。血管壁和外膜 K 与组织学斑块微血管密度显示出相似的中度强相关性（Pearson's ρ：0.59-0.65 [P<0.003] 和 0.52-0.64 [P<0.011]）。
血管壁和外膜 K 与组织学微血管密度的中度强相关性表明，这两个区域都反映了斑块的微血管密度。在比较研究之间的绝对数值时应谨慎。未来纳入风险分层阈值的研究需要就 DCE-MRI 参数的标准化达成一致。
2 技术功效：2 级。J. Magn. Reson. Imaging 2017；46：1053-1059.
