Department of Radiology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois; Department of Biomedical Engineering, Northwestern University, Evanston, Illinois.
Department of Radiology, Northwestern University, Feinberg School of Medicine, Chicago, Illinois.
J Vasc Interv Radiol. 2021 Jan;32(1):23-32.e1. doi: 10.1016/j.jvir.2020.09.016. Epub 2020 Nov 12.
To demonstrate a stronger correlation and agreement of yttrium-90 (Y) positron emission tomography (PET)/computed tomography (CT) measurements with explant liver tumor dosing compared with the standard model (SM) for radioembolization.
Hepatic VX2 tumors were implanted into New Zealand white rabbits, with growth confirmed by 7 T magnetic resonance imaging. Seventeen VX2 rabbits provided 33 analyzed tumors. Treatment volumes were calculated from manually drawn volumes of interest (VOI) with three-dimensional surface renderings. Radioembolization was performed with glass Y microspheres. PET/CT imaging was completed with scatter and attenuation correction. Three-dimensional ellipsoid VOI were drawn to encompass tumors on fused images. Tumors and livers were then explanted for inductively coupled plasma (ICP)-optical emission spectroscopy (OES) analysis of microsphere content. Y PET/CT and SM measurements were compared with reference standard ICP-OES measurements of tumor dosing with Pearson correlation and Bland-Altman analyses for agreement testing with and without adjustment for tumor necrosis.
The median infused activity was 33.3 MBq (range, 5.9-152.9). Tumor dose was significantly correlated with Y PET/CT measurements (r = 0.903, P < .001) and SM estimates (r = 0.607, P < .001). Bland-Altman analyses showed that the SM tended to underestimate the tumor dosing by a mean of -8.5 Gy (CI, -26.3-9.3), and the degree of underestimation increased to a mean of -18.3 Gy (CI, -38.5-1.9) after the adjustment for tumor necrosis.
Y PET/CT estimates were strongly correlated and had better agreement with reference measurements of tumor dosing than SM estimates.
与标准模型（SM）相比，证明钇-90（Y）正电子发射断层扫描（PET）/计算机断层扫描（CT）测量与肝肿瘤种植剂量的相关性更强，一致性更好。
将 VX2 肝肿瘤植入新西兰白兔体内，通过 7T 磁共振成像确认其生长情况。17 只 VX2 兔提供 33 个分析肿瘤。用三维表面渲染的方法，从手动绘制的感兴趣区域（VOI）中计算出治疗体积。用玻璃 Y 微球进行放射性栓塞治疗。进行 PET/CT 成像，并用散射和衰减校正。在融合图像上绘制三维椭球 VOI 以包围肿瘤。然后将肿瘤和肝脏取出，进行电感耦合等离子体（ICP）-发射光谱（OES）分析以测量微球含量。用 Pearson 相关和 Bland-Altman 分析比较 Y PET/CT 和 SM 测量值与参考标准 ICP-OES 测量值的一致性，同时也对有或无肿瘤坏死调整后的一致性进行了测试。
中位注入的活度为 33.3MBq（范围：5.9-152.9）。肿瘤剂量与 Y PET/CT 测量值（r=0.903，P<0.001）和 SM 估计值（r=0.607，P<0.001）显著相关。Bland-Altman 分析表明，SM 倾向于低估肿瘤剂量，平均低估-8.5Gy（CI：-26.3-9.3），调整肿瘤坏死后，低估程度增加到平均-18.3Gy（CI：-38.5-1.9）。
与 SM 估计值相比，Y PET/CT 估计值与肿瘤剂量的参考测量值具有更强的相关性和更好的一致性。
