Novel artifact‐robust and highly visible zinc solid fiducial marker for kilovoltage x‐ray image‐guided radiation therapy
Novel artifact‐robust and highly visible zinc solid fiducial marker for kilovoltage x‐ray image‐guided radiation therapy
复制标题
用于千伏 X 射线图像引导放射治疗的新型伪影稳健且高度可见的锌固体基准标记
DOI：
10.1002/mp.14412
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发表时间：
2020
期刊：
影响因子：
3.8
通讯作者：
Sasaki Ryohei
中科院分区：
文献类型：
--
作者：
Wang Tianyuan;Inubushi Sachiko;Ikeo Naoko;Mukai Toshiji;Okumura Keisuke;Akasaka Hiroaki;Yada Ryuichi;Yoshida Kenji;Miyawaki Daisuke;Ishihara Takeaki;Nakaoka Ai;Sasaki Ryohei
目的：开发一种新型的生物相容性固体基准标记物，以防止射线不透明的成像伪影，并在千伏x射线图像引导放射治疗中保持高成像对比度。方法用纯锌作基准标记物。设计了一个室内水等效模型来评估各种模拟处理方案下的伪影和能见度。根据千伏计算机断层扫描（CT）和锥形束CT （CBCT）扫描的金属伪影指数（MAI）对图像伪影进行定量评估。根据对比背景比（CBR）对两种类型的千伏平面x射线图像进行标记可见性评估。与传统的黄金基准标记进行了比较。结果使用锌而不是金标记物可以减轻成像伪影。在CT中，锌标记附近的MAI分别下降了76%、79%和77%，在CBCT全扇（半扇）扫描中，当使用一个、两个和三个标记的幻影设置时，MAI分别下降了77%（81）、74%（80）和79%(85)%。锌标记物的高对比度部分在四种（肺、组织、低密度骨和高密度骨）不同模拟情景下28/32暴露时的CBRs高于2.00，使其可见性与黄金标记物（30/32暴露时CBRs为bbb2.0）相当。结论：我们开发了一种生物相容性、伪迹稳健、高度可见的固体锌基准标记物。虽然需要在临床环境中进一步评估，但我们的研究结果表明其在千电压x射线图像引导放射治疗中的可行性和益处。
PurposeTo develop a novel biocompatible solid fiducial marker that prevents radiopaque imaging artifacts and also maintains high imaging contrast for kilovoltage x‐ray image‐guided radiation therapy.MethodsThe fiducial marker was made of pure zinc. An in‐house water‐equivalent phantom was designed to evaluate artifacts and visibility under various simulated treatment scenarios. Image artifacts were quantitatively assessed in terms of the metal artifact index (MAI) on kilovoltage computed tomography (CT) and cone‐beam CT (CBCT) scans. Marker visibility was evaluated on two types of kilovoltage planar x‐ray images in terms of the contrast‐to‐background ratio (CBR). Comparisons with a conventional gold fiducial marker were conducted.ResultsThe use of zinc rather than a gold marker mitigates imaging artifacts. The MAI near the zinc marker decreased by 76, 79, and 77 % in CT, and by 77 (81), 74 (80), and 79 (85) % in CBCT full‐fan (half‐fan) scans, when using one‐, two‐, and three‐marker phantom settings, respectively. The high‐contrast part of the zinc marker exhibited CBRs above 2.00 for 28/32 exposures under four (lung, tissue, low‐density bone, and high‐density bone) different simulation scenarios, making its visibility comparable to that of the gold marker (30/32 exposures with CBRs > 2.00).ConclusionsWe developed a biocompatible, artifact‐robust, and highly visible solid zinc fiducial marker. Although further evaluation is needed in clinical settings, our findings suggest its feasibility and benefits for kilovoltage x‐ray image‐guided radiation therapy.