Faculty Electrical Engineering, Signal Processing Systems group (SPS), Eindhoven University of Technology (TU/e), Laplace Building 028, Postbox 513, 5600MB, Eindhoven, The Netherlands.
Neuroradiology. 2012 Feb;54(2):155-62. doi: 10.1007/s00234-011-0839-1. Epub 2011 Feb 18.
To assess an optimized 3D imaging protocol for intracranial nitinol stents in 3D C-arm flat detector imaging. For this purpose, an image quality simulation and an in vitro study was carried out.
Nitinol stents of various brands were placed inside an anthropomorphic head phantom, using iodine contrast. Experiments with objects were preceded by image quality and dose simulations. We varied X-ray imaging parameters in a commercially interventional X-ray system to set 3D image quality in the contrast-noise-sharpness space. Beam quality was varied to evaluate contrast of the stents while keeping absorbed dose below recommended values. Two detector formats were used, paired with an appropriate pixel size and X-ray focus size. Zoomed reconstructions were carried out and snapshot images acquired. High contrast spatial resolution was assessed with a CT phantom.
We found an optimal protocol for imaging intracranial nitinol stents. Contrast resolution was optimized for nickel-titanium-containing stents. A high spatial resolution larger than 2.1 lp/mm allows struts to be visualized. We obtained images of stents of various brands and a representative set of images is shown. Independent of the make, struts can be imaged with virtually continuous strokes. Measured absorbed doses are shown to be lower than 50 mGy Computed Tomography Dose Index (CTDI).
By balancing the modulation transfer of the imaging components and tuning the high-contrast imaging capabilities, we have shown that thin nitinol stent wires can be reconstructed with high contrast-to-noise ratio and good detail, while keeping radiation doses within recommended values. Experimental results compare well with imaging simulations.
评估 3D C 臂平板探测器成像中颅内镍钛合金支架的优化 3D 成像方案。为此，进行了图像质量模拟和体外研究。
将各种品牌的镍钛合金支架用碘对比剂放置在人体头部模型内。在进行物体实验之前，进行了图像质量和剂量模拟。我们在商业介入 X 射线系统中改变 X 射线成像参数，以在对比度-噪声-锐度空间中设置 3D 图像质量。改变射线质量以评估支架的对比度，同时将吸收剂量保持在推荐值以下。使用两种探测器格式，与适当的像素大小和 X 射线焦点大小相匹配。进行了缩放重建并获取了快照图像。使用 CT 体模评估高对比度空间分辨率。
我们找到了一种优化的颅内镍钛合金支架成像方案。对于含镍钛的支架，优化了对比度分辨率。高空间分辨率大于 2.1lp/mm 可使支架的支柱可视化。我们获得了各种品牌的支架图像，并展示了一组有代表性的图像。无论品牌如何，都可以使用几乎连续的笔划对支柱进行成像。测量的吸收剂量显示低于 50mGy 计算机断层扫描剂量指数（CTDI）。
通过平衡成像组件的调制传递和调整高对比度成像能力，我们表明可以用高对比度噪声比和良好的细节重建薄的镍钛合金支架线，同时将辐射剂量保持在推荐值内。实验结果与成像模拟吻合良好。
