Quantification of Myocardial Perfusion

我们已经开发并验证了一系列定量灌流方法，包括双推注方案(Christian TF等人)。放射学。2004年；232(3)：677-84)。我们证明了所有来自临床前研究的结论在人身上都是适用和相关的(Hsu，L等人)。J Magn Reson成像2006；23(3)：315-22)。以前的定量血流灌注分析(包括我们自己的工作)的一个共同问题是依赖于感兴趣区域分析或基于扇区的分析。这些类型的基于扇区的分析相当于将图像分辨率降低了10-50倍，并导致心肌灌注的表示相当不完整。 由于医生通常通过观看在数字视频环路中以全分辨率播放的一系列图像来解释灌注图像，因此我们假设MRI可以基于对比度增强的首过心脏磁共振(CMR)成像在像素水平上评估狗和患者的完全定量心肌血流量(MBF)。我们发现，心肌血流可以在像素水平(32微升心肌)在CMR灌注图像上进行量化，结果与微球测量结果相吻合(Hsu，L等人)。JACC CV Imaging 2012)。此外，高分辨率的像素方向CMR灌注图可以检测到跨壁的灌注梯度。这些方法可提高患者诊断冠心病的客观性。 我们已经研究了不理想的表面线圈强度校正对心肌灌注定量的影响(Miller CA等人。JCMR 2015)。我们还开发了更好的质子密度加权方法，以提高在血流定量所需的校准步骤中应用这些表面线圈强度校正的准确性(Nielle-Vallespin等人)。JCMR 2015)。 自2015年以来，我们验证了用于量化心肌灌注的自动系统的单个组件。这在一篇总结全自动负荷灌注CMR诊断准确性的论文(Hsu 2018)中达到了顶峰。这些方法也提供了洞察力，可能有助于区分伪影和真正的血流灌注缺陷。

We have developed and validated a series of quantitative perfusion methods including a dual bolus protocol (Christian TF et al. Radiology. 2004; 232(3):677-84). We demonstrated that all of the conclusions from the pre-clinical studies were applicable and relevant in people (Hsu L et al. J Magn Reson Imaging 2006; 23(3):315-22). One problem common to prior quantitative perfusion analyses (including our own work) has been reliance on region of interest analysis or sector-based analysis. These types of sector-based analyses are equivalent to degrading the image resolution by a factor of 10-50 and result in rather blocky representations of myocardial perfusion. Since physicians generally interpret perfusion images by watching a series of images played in a digital video loop at full resolution, we hypothesized that MRI could evaluate fully quantitative myocardial blood flow (MBF) at a pixel level based on contrast-enhanced first-pass cardiac magnetic resonance (CMR) imaging in dogs and patients. We found that myocardial blood flow could be quantified at the pixel level (32 microliters of myocardium) on CMR perfusion images and results compared well with microsphere measurements (Hsu L et al. JACC CV Imaging 2012). Furthermore, high-resolution pixel-wise CMR perfusion maps could detect transmural perfusion gradients. These methods may improve the objectivity of diagnosing CAD in patients. We have studied the consequences of imperfect surface coil intensity corrections on quantification of myocardial perfusion (Miller CA et al. JCMR 2015). We have also developed substantially better proton density weighted methods to improve the accuracy with which these surface coil intensity corrections can be applied during the calibration steps necessary for perfusion quantification (Nielles-Vallespin et al. JCMR 2015). Since 2015, we validated individual components of an automatic system for quantifying myocardial perfusion. This culminated in a paper summarizing the diagnostic accuracy of fully automatic stress perfusion CMR (Hsu 2018). These methods have also provided insight that may be useful for differentiating artifacts from true perfusion defects.