Veres Dániel S, Máthé Domokos, Futó Ildikó, Horváth Ildikó, Balázs Akos, Karlinger Kinga, Szigeti Krisztián
Department of Biophysics and Radiation Biology, Semmelweis University, 1094, Budapest, Hungary.
Mol Imaging Biol. 2014 Apr;16(2):167-72. doi: 10.1007/s11307-013-0679-y.
The aim of this paper is to present a simple and quantitative data analysis method with a new potential in the application of liver single-photon emission computed tomography (SPECT) imaging. We have established quantitative SPECT/computed tomography (CT) in vivo imaging protocols for determination of liver tumor burden based on the known role of Kupffer cells in cancer of the liver.
As it is also known that functional Kupffer cells accumulate particulate material contained in the arterial blood of liver supply, we used radiolabeled macro-aggregated albumin particles ([(99m)Tc]-MAA) injected intravenously to image liver disease. Quantification of cold spot liver lesion imaging was also a general objective.
We examined a healthy control group (BALB/C mice, n = 6) and group of induced hepatocellular carcinoma (HCC, matrilin-2 transgenic KO mice, n = 9), where hepatocellular carcinoma was induced by diethylnitrosamine. We used [(99m)Tc]-MAA as radiopharmaceutical for liver SPECT imaging in a small animal SPECT/CT system. A liver radioactivity overview map was generated. Segmentation of the liver was calculated by Otsu thresholding method. Based on the segmentation the radioactivity volume and the summarized liver activity were determined.
Tumor burden of the livers was quantitatively determined by creating parametric data from the resulting volumetric maps. Ex vivo liver mass data were applied for the validation of in vivo measurements. An uptake with cold spots as tumors was observed in all diseased animals in SPECT/CT scans. Isotope-labeled particle uptake (standardized uptake concentration) of control (median 0.33) and HCC (median 0.18) groups was significantly different (p = 0.0015, Mann Whitney U test).
A new potential application of [(99m)Tc]-MAA was developed and presents a simple and very effective means to quantitatively characterize liver cold spot lesions resulting from Kupffer cell dysfunctions as a consequence of tumor burden.
本文旨在介绍一种简单且定量的数据分析方法，该方法在肝脏单光子发射计算机断层扫描（SPECT）成像应用中具有新的潜力。基于库普弗细胞在肝癌中的已知作用，我们已建立用于确定肝脏肿瘤负荷的定量SPECT/计算机断层扫描（CT）体内成像方案。
由于已知功能性库普弗细胞会积累肝供血动脉血中所含的颗粒物质，我们通过静脉注射放射性标记的大颗粒聚合白蛋白颗粒（[(99m)Tc]-MAA）来对肝脏疾病进行成像。对冷区肝脏病变成像进行定量也是一个总体目标。
我们检查了一个健康对照组（BALB/C小鼠，n = 6）和一组诱导性肝细胞癌（HCC，matrilin-2转基因敲除小鼠，n = 9），其中肝细胞癌由二乙基亚硝胺诱导产生。我们使用[(99m)Tc]-MAA作为放射性药物，在小动物SPECT/CT系统中进行肝脏SPECT成像。生成了肝脏放射性概况图。通过大津阈值法计算肝脏的分割。基于该分割确定放射性体积和肝脏总活性。
通过从所得体积图创建参数数据来定量确定肝脏的肿瘤负荷。离体肝脏质量数据用于体内测量的验证。在SPECT/CT扫描中，所有患病动物均观察到以冷区为肿瘤的摄取情况。对照组（中位数0.33）和HCC组（中位数0.18）的同位素标记颗粒摄取（标准化摄取浓度）有显著差异（p = 0.0015，曼-惠特尼U检验）。
开发了[(99m)Tc]-MAA的一种新的潜在应用，它是一种简单且非常有效的方法，可定量表征因肿瘤负荷导致库普弗细胞功能障碍而产生的肝脏冷区病变。
