Ginsburg Shoshana B, Taimen Pekka, Merisaari Harri, Vainio Paula, Boström Peter J, Aronen Hannu J, Jambor Ivan, Madabhushi Anant
Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, USA.
Department of Pathology, University of Turku and Turku University Hospital, Turku, Finland.
J Magn Reson Imaging. 2016 Dec;44(6):1405-1414. doi: 10.1002/jmri.25330. Epub 2016 Jun 10.
To develop and evaluate a prostate-based method (PBM) for estimating pharmacokinetic parameters on dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) by leveraging inherent differences in pharmacokinetic characteristics between the peripheral zone (PZ) and transition zone (TZ).
This retrospective study, approved by the Institutional Review Board, included 40 patients who underwent a multiparametric 3T MRI examination and subsequent radical prostatectomy. A two-step PBM for estimating pharmacokinetic parameters exploited the inherent differences in pharmacokinetic characteristics associated with the TZ and PZ. First, the reference region model was implemented to estimate ratios of K between normal TZ and PZ. Subsequently, the reference region model was leveraged again to estimate values for K and v for every prostate voxel. The parameters of PBM were compared with those estimated using an arterial input function (AIF) derived from the femoral arteries. The ability of the parameters to differentiate prostate cancer (PCa) from benign tissue was evaluated on a voxel and lesion level. Additionally, the effect of temporal downsampling of the DCE MRI data was assessed.
Significant differences (P < 0.05) in PBM K between PCa lesions and benign tissue were found in 26/27 patients with TZ lesions and in 33/38 patients with PZ lesions; significant differences in AIF-based K occurred in 26/27 and 30/38 patients, respectively. The 75 and 100 percentiles of K and v estimated using PBM positively correlated with lesion size (P < 0.05).
Pharmacokinetic parameters estimated via PBM outperformed AIF-based parameters in PCa detection. J. Magn. Reson. Imaging 2016;44:1405-1414.
通过利用外周带（PZ）和移行带（TZ）药代动力学特征的固有差异，开发并评估一种基于前列腺的方法（PBM），用于在动态对比增强（DCE）磁共振成像（MRI）上估计药代动力学参数。
这项经机构审查委员会批准的回顾性研究纳入了40例接受多参数3T MRI检查及随后根治性前列腺切除术的患者。用于估计药代动力学参数的两步PBM利用了与TZ和PZ相关的药代动力学特征的固有差异。首先，实施参考区域模型以估计正常TZ和PZ之间的K比率。随后，再次利用参考区域模型来估计每个前列腺体素的K和v值。将PBM的参数与使用源自股动脉的动脉输入函数（AIF）估计的参数进行比较。在体素和病变水平上评估这些参数区分前列腺癌（PCa）与良性组织的能力。此外，评估了DCE MRI数据时间下采样的影响。
在26/27例TZ病变患者和33/38例PZ病变患者中，发现PCa病变与良性组织之间的PBM K存在显著差异（P < 0.05）；基于AIF的K在26/27例和30/38例患者中分别出现显著差异。使用PBM估计的K和v的第75和第100百分位数与病变大小呈正相关（P < 0.05）。
在PCa检测中，通过PBM估计的药代动力学参数优于基于AIF的参数。《磁共振成像杂志》2016年；44：1405 - 1414。
