高级检索

基于三维关键点的CBCT重定向及二维头影测量模拟

CBCT Reorientation Based on 3D Landmarks and 2D Cephalometry Simulation

  • 摘要: 针对口腔正畸学的三维影像测量分析法尚不成熟,而二维影像因维度限制存在模糊、失真的问题,提出了基于三维关键点的锥形束计算机断层扫描(CBCT)重定向及二维头影测量模拟可视化方法。首先使用深度学习方法在三维影像上预测特定关键点,并根据关键点与头位的对应关系建立参考坐标系,重定向形成头位统一的CBCT数据;然后通过算法模拟二维头影测量片成像过程,产生渲染图像;再通过非线性映射、区域增强等后处理方法,生成便于观察测量的模拟二维头影测量片。所提方法在84套CBCT的非公开数据集上达到均值0.8°,标准差0.5°的重定向欧拉角误差,生成的模拟图像可直接用于现有二维头影测量手动及自动方法,在7种质量评价的用户调研中有80%均认为其优于二维影像。

     

    Abstract: Three-dimensional imaging analysis for orthodontics remains underdeveloped, while two-dimensional imaging suffers from blurring and distortion due to dimensional limitations. This study proposed a cone-beam computed tomography (CBCT) reorientation based on 3D landmarks and 2D cephalometry simulation visualization method. First, a deep learning approach predicted specific landmarks on 3D images. A reference coordinate system was established according to the correspondence between these landmarks and head posture, and CBCT data was reoriented to achieve standardized head alignment. Next, an algorithm simulated the imaging process of a 2D cephalometric radiograph to produce rendered images. Then, through post-processing methods such as including nonlinear mapping and regional enhancement, generated simulated 2D cephalometric images suitable for observation and measurement. The proposed method achieved a reorientation Euler angle error of mean 0.8° and standard deviation 0.5° on a non-public dataset of 84 CBCT scans. The generated simulated images can be directly used in existing manual and automatic 2D cephalometric analysis methods. In a user study evaluating seven quality metrics, 80% of respondents rated the simulated images superior to conventional 2D radiographs.

     

/

返回文章
返回