Tissue mimicking materials for a multi-imaging modality prostate phantom
Tissue mimicking materials for a multi-imaging modality prostate phantom
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DOI：
10.1118/1.1354998
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发表时间：
2001-04-01
期刊：
影响因子：
3.8
通讯作者：
Thomadsen, BR
中科院分区：
文献类型：
--
作者：
D'Souza, WD;Madsen, EL;Thomadsen, BR
已经开发了用于在前列腺体模中使用的用于磁共振成像（MRI）、超声（US）和计算机断层扫描（CT）的同时模拟体内软组织的材料。前列腺和肌肉模拟材料含有水、琼脂糖、脂质颗粒、蛋白质、Cu++、EDTA、玻璃珠和硫柳汞（防腐剂）。脂肪被模拟与红花油弥漫的随机网格（网络）的聚氨酯。在22 ℃下测量体模材料特性。(22摄氏度是使用幻影的典型室温。材料特性值应尽可能与体温（37 ℃）下的组织值相匹配。对于MRI，感兴趣的主要属性是T1和T2弛豫时间，对于US，它们是衰减系数、传播速度和反向散射，对于CT，是X射线衰减。考虑到大量的参数被模仿，相当好的协议，发现与实际组织的值从文献中获得。使用已发表的前列腺实质的值，在37 ℃和40 MKz下的T1和T2估计分别约为1100和98 ms。体内前列腺的CT值估计为45 HU（亨氏单位）。该仿前列腺材料在22 ℃、40 MHz时的T1为937 ms，T2为88 ms，传播速度和衰减系数斜率分别为1540 m/s和0.36dB/cm/MHz，仿前列腺组织的CT值为43 HU。组织模拟（TM）肌肉与TM前列腺的不同之处在于干重琼脂糖、Cu++、EDTA的含量以及玻璃珠的质量和数量。TM肌肉中使用的18 μ m玻璃珠增加了US反向散射和US衰减;玻璃珠的存在对T1也有一定影响，但对T2没有影响。所开发的组织模拟材料的组成使得不同版本可以在体模中彼此直接接触，而US、MRI或CT特性不会发生长期变化。因此，拟人化的幻影可以被构建。(C)2001年美国医学物理学家协会。
Materials that simultaneously mimic soft tissue in vivo for magnetic resonance imaging (MRI), ultrasound (US), and computed tomography (CT) for use in a prostate phantom have been developed. Prostate and muscle mimicking materials contain water, agarose, lipid particles, protein, Cu++, EDTA, glass beads, and thimerosal (preservative). Fat was mimicked with safflower oil suffusing a random mesh (network) of polyurethane. Phantom material properties were measured at 22 degreesC. (22 degreesC is a typical room temperature at which phantoms are used.) The values of material properties should match, as well as possible, the values for tissues at body temperature, 37 degreesC. For MRI, the primary properties of interest are T1 and T2 relaxations times, for US they are the attenuation coefficient, propagation speed, and backscatter, and for CT, the x-ray attenuation. Considering the large number of parameters to be mimicked, rather good agreement was found with actual tissue values obtained from the literature. Using published values for prostate parenchyma, T1 and T2 at 37 degreesC and 40 MKz are estimated to be about 1100 and 98 ms, respectively. The CT number for in vivo prostate is estimated to be 45 HU (Hounsfield units). The prostate mimicking material has a T1 of 937 ms and a T2 of 88 ms at 22 degreesC and 40 MHz; the propagation speed and attenuation coefficient slope are 1540 m/s and 0.36 dB/cm/MHz, respectively, and the CT number of tissue mimicking prostate is 43 HU. Tissue mimicking (TM) muscle differs from TM prostate in the amount of dry weight agarose, Cu++, EDTA, and the quality and quantity of glass beads. The 18 mum glass beads used in TM muscle increase US backscatter and US attenuation; the presence of the beads also has some effect on T1 but no effect on T2. The composition of tissue-mimicking materials developed is such that different versions can be placed in direct contact with one another in a phantom with no long term change in US, MRI, or CT properties. Thus, anthropomorphic phantoms can be constructed. (C) 2001 American Association of Physicists in Medicine.