基于二维超声- 三维 CT 配准的肾脏穿刺定位方法可行性研究

医学影像引导的经皮肾穿刺手术是经皮肾镜取石术中建立手术通道的重要手段，高质量的 实时医学图像可以提高术中穿刺精度，减少手术风险。针对自由呼吸下经皮肾穿刺靶点的导航定位问 题，该研究提出了一种基于术中二维超声-术前三维 CT 实时配准的肾脏穿刺定位方法。首先对肾脏轮 廓特征的二维超声图像和三维 CT 图像进行由粗到精的快速配准，然后通过超声探头标定，将配准融合 后的图像注册到手术空间，实现穿刺靶点的实时定位。人体腹部模型实验结果表明，超声探头标定均 方根误差为 0.998 mm，二维超声和三维 CT 数据配准误差为 0.709 mm，平均配准运算时间为 1.15 s，最 终的平均定位误差为 2.265 mm。

A Feasibility Study of Renal Puncture Localization Method Based on 2D Ultrasound-3D CT Registration

Medical image-guided percutaneous renal puncture is an important technique to establish surgical channels in the percutaneous nephrolithotomy. High quality and real-time medical image can improve the accuracy of intraoperative puncture and reduce surgical risks. Aiming at the navigation and positioning problem of percutaneous renal puncture under free breathing, a renal puncture positioning method based on the intraoperative 2D ultrasound and the preoperative 3D CT image is introduced. In the first step, a real-time registration method was applied to the 2D ultrasound and the preoperative 3D CT image to realize rapid registration and fusion. Then the fusion image is registered in the surgical space through ultrasound probe calibration and spatial coordinate transformation, which realized the real-time positioning of puncture targets. Finally, the human abdomen model was used for the experiments, and the results showed that the root mean square error of the ultrasound probe calibration is 0.998 mm. The registration error of 2D ultrasound and 3D CT images is 0.709 mm, the average registration time was 1.15 s, and the final average positioning error is 2.265 mm.