ARTORG Center for Computer Aided Surgery, University of Bern, Bern, Switzerland.
IEEE Trans Biomed Eng. 2013 Apr;60(4):969-76. doi: 10.1109/TBME.2012.2235439. Epub 2012 Dec 20.
The application of image-guided systems with or without support by surgical robots relies on the accuracy of the navigation process, including patient-to-image registration. The surgeon must carry out the procedure based on the information provided by the navigation system, usually without being able to verify its correctness beyond visual inspection. Misleading surrogate parameters such as the fiducial registration error are often used to describe the success of the registration process, while a lack of methods describing the effects of navigation errors, such as those caused by tracking or calibration, may prevent the application of image guidance in certain accuracy-critical interventions. During minimally invasive mastoidectomy for cochlear implantation, a direct tunnel is drilled from the outside of the mastoid to a target on the cochlea based on registration using landmarks solely on the surface of the skull. Using this methodology, it is impossible to detect if the drill is advancing in the correct direction and that injury of the facial nerve will be avoided. To overcome this problem, a tool localization method based on drilling process information is proposed. The algorithm estimates the pose of a robot-guided surgical tool during a drilling task based on the correlation of the observed axial drilling force and the heterogeneous bone density in the mastoid extracted from 3-D image data. We present here one possible implementation of this method tested on ten tunnels drilled into three human cadaver specimens where an average tool localization accuracy of 0.29 mm was observed.
图像引导系统的应用，无论是否有手术机器人的支持，都依赖于导航过程的准确性，包括患者到图像的配准。外科医生必须根据导航系统提供的信息进行手术，通常无法通过目视检查以外的方式验证其正确性。误导性的替代参数，如基准注册误差，常被用来描述注册过程的成功，而缺乏描述导航误差影响的方法，如由于跟踪或校准引起的误差，可能会限制图像引导在某些对精度有要求的干预中的应用。在进行经乳突腔耳蜗植入的微创手术时，根据基于颅骨表面标志的配准，从乳突外部直接钻一个通向耳蜗目标的隧道。使用这种方法，无法检测钻头是否在正确的方向前进，也无法避免面神经损伤。为了解决这个问题，提出了一种基于钻孔过程信息的工具定位方法。该算法基于观测到的轴向钻孔力与从 3D 图像数据中提取的乳突中异质骨密度之间的相关性，来估计机器人辅助手术工具在钻孔任务中的姿态。我们在此介绍了在三个人体标本上进行的十次钻孔测试中，该方法的一种可能实现方式，观察到的工具定位平均精度为 0.29 毫米。
