基于术中CT自动配准的主动红外线光学导航系统精度影响因素分析

Clinical factors affecting clinical accuracy of an intraoperative 3D image-based auto-registration active infrared navigation system

目的评估常见临床因素对术中基于CT自动配准的主动红外线光学导航系统临床精度的影响。方法在临床手术室环境下,以腰椎等比例Sawbone模型作为体模,采用标准手术体位和设备位置,以3D NAV导航系统的术中CT自动配准导航模式模拟临床导航操作验证多种临床因素对导航精度的影响。模型表面嵌入多枚钛合金标记珠,使用导航软件分别测量钛珠在CT图像中和导航系统中的坐标,计算坐标距离作为导航临床精度。然后在无影灯照射、手术床位姿、导航相机位姿三种临床因素下测量导航临床精度,并与初始状态的精度比较。结果初始状态导航临床精度为0.64 mm±0.30 mm;无影灯照射手术区后,导航临床精度为0.63 mm±0.25 mm;手术床降低10 cm和左倾15°时,导航临床精度分别为0.61 mm±0.21 mm和0.63 mm±0.21 mm;相机分别向左侧和向上旋转到示踪器恰好可见的位置时,导航临床精度分别为0.65 mm±0.30 mm和0.62 mm±0.21 mm;相机分别移动到距示踪器1 m和2 m的位置时,导航临床精度分别为0.64 mm±0.24 mm和0.67 mm±0.28 mm。在各因素影响下该导航系统的临床精度均与初始状态无显著性差异(n=108,P>0.05)。合并全部864次测量的导航临床精度为0.64 mm±0.25 mm。结论本研究中的导航系统临床精度不受无影灯照射、手术床位姿和导航相机位姿的影响。

Objective To evaluate the impact of common clinical factors on the clinical accuracy of an active infrared optical navigation system based on intraoperative CT automatic registration.Methods In a clinical operating room environment,a lumbar spine proportional Sawbone model was used as a phantom,standard surgical positions and equipment locations were adopted,and 3D NAV navigation system’s intraoperative CT automatic registration navigation mode was used to simulate clinical navigation operations to investigate the influence of various clinical factors on navigation accuracy.Multiple titanium alloy markers were embedded into the model surface,and their coordinates were measured in both CT images and the navigation system using navigation software.Coordinate distance was calculated as the navigation clinical accuracy.The navigation clinical accuracy was then measured under three clinical factors:shadowless light irradiation,surgical bed posture,and navigation camera posture,and compared with the initial accuracy.Results The clinical accuracy of the initial state was 0.64 mm±0.30 mm.When the surgical area was irradiated by the shadowless light,the navigation clinical accuracy was 0.63 mm±0.25 mm.When the surgical bed was lowered by 10 cm and tilted 15°to the left,the navigation clinical accuracy was 0.61 mm±0.21 mm and 0.63 mm±0.21 mm,respectively.When the camera was rotated to the left side and upward to the position where the tracer was just visible,the navigation clinical accuracy was 0.65 mm±0.30 mm and 0.62 mm±0.21 mm,respectively.When the camera was moved to the position 1 m and 2 m away from the traker,the navigation clinical accuracy was 0.64mm±0.24mm and 0.67 mm±0.28 mm,respectively.The clinical accuracy of the navigation system under varies clinical factors was not significantly different from the initial state(n=108,P>0.05).The combined navigation clinical accuracy of all 864 measurements was 0.64 mm±0.25 mm.Conclusions The clinical accuracy of the navigation system in this study was not affected by the illumination of the operating light,the position of the surgical bed,or the position of the camera.