Lee J S, Lee D S, Ahn J Y, Cheon G J, Kim S-K, Yeo J S, Park K S, Chung J-K, Lee M C
Department of Nuclear Medicine, Seoul National University College of Medicine, Seoul, Korea.
Med Biol Eng Comput. 2005 Sep;43(5):678-85. doi: 10.1007/BF02351043.
Algorithm-based parametric imaging of myocardial blood flow (MBF), as measured by H2(15)O PET, has been the goal of many research efforts. A method for generating parametric images of regional MBF by factor and cluster analysis on H2(15)O dynamic myocardial PET was validated by its comparison with gold-standard MBF values determined invasively using radiolabelled microspheres. Right and left ventricular blood pool activities and their factor images were obtained by the application of factor analysis to dynamic frames. By subtraction of the factor images multiplied by their corresponding values on the factors from the original dynamic images for each frame, pure tissue dynamic images were obtained, from which arterial blood activities were excluded. Cluster analysis that averaged pixels having time-activity curves with the same shape was applied to pure tissue images to generate parametric MBF images. The usefulness of this method for quantifying regional MBF was evaluated using canine experiment data. H2(15)O PET scans and microsphere studies were performed on seven dogs at rest and after pharmacological stress. The image qualities and the contrast of parametric images obtained using the proposed method were significantly improved over either the tissue factor images or the parametric images obtained using a conventional method. Regional MBFs obtained using the proposed method correlated well with those obtained by the region of interest method (r = 0.94) and by the microsphere technique (r = 0.90). A non-invasive method is presented for generating parametric images of MBF from H2(15)O PET, using factor and cluster analysis.
通过H₂¹⁵O正电子发射断层扫描（PET）测量的基于算法的心肌血流（MBF）参数成像一直是众多研究努力的目标。一种通过对H₂¹⁵O动态心肌PET进行因子和聚类分析来生成局部MBF参数图像的方法，通过与使用放射性标记微球进行有创测量确定的金标准MBF值进行比较得到了验证。通过对动态帧应用因子分析获得左右心室血池活动及其因子图像。通过从每一帧的原始动态图像中减去乘以其在因子上相应值的因子图像，得到纯组织动态图像，从中排除了动脉血活动。将具有相同形状时间 - 活动曲线的像素进行平均的聚类分析应用于纯组织图像以生成MBF参数图像。使用犬实验数据评估了该方法对量化局部MBF的有效性。对7只狗在静息状态和药物应激后进行了H₂¹⁵O PET扫描和微球研究。与组织因子图像或使用传统方法获得的参数图像相比，使用所提出方法获得的参数图像的图像质量和对比度有显著提高。使用所提出方法获得的局部MBF与通过感兴趣区域法（r = 0.94）和微球技术（r = 0.90）获得的结果相关性良好。提出了一种使用因子和聚类分析从H₂¹⁵O PET生成MBF参数图像的非侵入性方法。
