A two-dimensional antiscatter grid for dental cone beam computed tomography

项目摘要 锥形束计算机断层扫描（CBCT）是牙科和口腔医学中常用的3D X射线成像模式， 颅面成像虽然CBCT主要用于在3D中评价骨解剖结构，但软组织通常 在牙科CBCT图像中显示不佳。此外，无法从CBCT准确提取组织密度 图像.这个问题背后的罪魁祸首是散射辐射。患者发出的散射X射线 被X射线传感器记录，严重降低了图像信号的保真度。 因此，在这个项目中，我们提出了一种新的二维抗散射网格（2D网格），以大大提高 牙科CBCT图像质量。我们提出的2D网格将有效地衰减散射的X射线，同时传输 主要的或有用的X射线到图像传感器。一旦成功实施，我们的2D网格将提供 显着改善软组织可视化、准确的骨密度测量，并减少图像 藏物或者，我们的2D网格可以减少成像辐射剂量，同时提供相当的对比度， 相对于当前牙科CBCT图像的噪声比。 为了实现我们提出的二维网格技术，（1）我们将研究二维网格的最佳物理特性， 网格，以实现有效的散射抑制和高初级传输。(2)我们将评估 体模成像实验中2D网格提供CBCT图像质量的改善。

Project summary Cone beam computed tomography (CBCT) is a commonly used 3D x-ray imaging modality in dental and craniofacial imaging. While CBCT is primarily employed in evaluating bony anatomy in 3D, soft tissues are often poorly visualized in dental CBCT images. Moreover, tissue densities cannot be extracted accurately from CBCT images. The main culprit behind this problem is scattered radiation. Scattered x-rays emanating from the patient are registered by the x-ray sensor, severely degrading the fidelity of image signals. Thus, in this project, we propose a novel two-dimensional antiscatter grid (2D grid) to substantially improve the dental CBCT image quality. Our proposed 2D grid will attenuate scattered x-rays effectively, while transmitting primary, or useful, x-rays to the image sensor. Once successfully implemented, our 2D grid will provide significantly improved soft tissue visualization, accurate bone density measurement, and will reduce image artifacts. Alternatively, our 2D grid can reduce imaging radiation dose while providing comparable contrast-to- noise ratio with respect to current dental CBCT images. To implement our proposed 2D grid technology, (1) we will investigate the optimal physical characteristics of 2D grids to achieve effective scatter suppression and high primary transmission. (2) We will evaluate the improvement in CBCT image quality provided by 2D grid in phantom imaging experiments.