Fiberglass limb phantoms: fabrication and use for quantitative scintigraphy.
Fiberglass limb phantoms: fabrication and use for quantitative scintigraphy.
复制标题
玻璃纤维肢体模型：定量闪烁扫描的制造和使用。
DOI：
10.1118/1.596274
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发表时间：
1988
期刊：
影响因子：
3.8
通讯作者：
Conlon,KC
中科院分区：
文献类型：
--
作者：
Bading,JR;DiResta,GR;Corbally,MT;Conlon,KC
定量放射性核素闪烁成像通常需要从模拟感兴趣区域的放射性分布、组织几何形状和组织组成的幻影中获得经验校准因子。本文描述了一种方法，其中用玻璃纤维胶带制成的铸件用于形成逼真的，可充水的四肢幻影。在开发新的放射成像技术时，经常使用的是狗和兔子的后腿。从安乐死动物身上取下的腿骨按解剖结构安装在石膏内。通过x射线计算机断层扫描确定幻腔的尺寸。开发了一种程序，用于定向幽灵以匹配给定实验装置的后腿几何形状。使用图像活动校准的幻影说明了几何平均计数技术，用于确定狗大腿软组织区域的99mtc活动密度。将标定技术推广到平面和层析成像是很简单的。通过外部计数获得的99mtc活性密度的现场测量值与切除组织的体外放射测定进行比较。从4只狗身上获得的22个组织样本中，它们的体外位置数据在50倍的活动密度范围内呈线性相关（r=0.98,p≪0.001）。观察到的百分比差异[%差异=100（原位-体外）/体外]的平均值和标准差分别为（7.8±2.9）和（13.7±2.1）。一项补充调查表明，这些差异是由各种单独的小误差来源共同造成的。综上所述，在实验室环境下，用玻璃纤维胶带可以很容易地制造出具有模拟肢体不规则外轮廓的腔体的持久幻影。使用这种幻影可以测量肢体的局部活动，平均误差小于15%。
Quantitative radionuclide scintigraphy often requires empirical calibration factors derived from phantoms which simulate the radioactivity distribution, tissue geometry and tissue composition of the region of interest. This paper describes a method in which casts made with fiberglass tape are used to form realistic, water‐fillable phantoms of the limbs. Phantoms were constructed for the hind legs of the dog and rabbit, species frequently used in developing new radioscintigraphic techniques. Leg bones removed from euthanized animals were mounted anatomically within the casts. The dimensions of the phantom cavities were determined by x‐ray computed tomography. A procedure was developed for orienting the phantoms to match the hind leg geometry of a given experimental setup. Use of the phantoms for image activity calibration is illustrated for a geometric‐mean counting technique used to determine99mTc activity densities in soft‐tissue regions of the dog thigh. Generalization of the calibration technique to planar and tomographic imaging is straightforward.Insitumeasurements of99mTc activity density obtained by external counting were compared within vitroradioassays of excised tissue. For 22 tissue samples obtained from four dogs, thein situandin vitrodata were linearly correlated (r=0.98,p≪0.001) over a 50‐fold range of activity density. The mean and standard deviation of the observed percent discrepancies [% discrepancy=100(in situ−in vitro)/in vitro] were (7.8±2.9) and (13.7±2.1), respectively. A supplementary investigation indicated that the discrepancies resulted from a combination of various, individually small sources of error. In conclusion, durable phantoms with cavities closely simulating the irregular outer contours of the limbs can readily be fabricated with fiberglass tape in the laboratory setting. Use of such phantoms permits measurement of regional activities in the limbs with an average error of <15%.