Willems P W, Noordmans H J, Berkelbach van der Sprenkel J W, Viergever M A, Tulleken C A
Department of Neurosurgery and Image Sciences Institute, University Medical Center, Utrecht, The Netherlands.
J Neurosurg. 2001 Dec;95(6):1067-74. doi: 10.3171/jns.2001.95.6.1067.
To enable the use of the Mehrkoordinaten Manipulator (MKM) robotic navigation system for frameless point stereotactic procedures, a new instrument holder is presented. A phantom-based accuracy study was performed in which this new method was compared with frame-based procedures performed using the Brown-Roberts-Wells (BRW) stereotactic frame. The authors acquired computerized tomography scans of a test phantom, consisting of 19 acrylic plastic target rods on a circular base. These images were used in frame-based (BRW) and frameless (MKM) localization experiments. In both cases the authors calculated the distances between the actual target positions and the positions reached stereotactically. The mean application accuracy (target registration error) was 0.68 mm when the BRW frame was used and 0.96 mm when the MKM system was used after manual repositioning of the microscope (p < 0.001). Positioning accomplished using robotics only demonstrated a slightly larger inaccuracy: 1.47 mm (p < 0.005). Because the surgeon is concerned with the largest error in an individual case rather than the mean error in a large number of cases, the mean + three standard deviations was also compared. This value differed very little between the manually positioned MKM system and the BRW frame (2.04 mm and 1.84 mm, respectively). Although repeatability per target appeared to be slightly better when the BRW frame was used, accuracy was more homogeneous over the phantom volume when the MKM system was used (both differences were not significant). In conclusion, the accuracy of point stereotactic procedures performed using an instrument holder attached to the system is comparable with the accuracy of procedures involving a stereotactic frame. Moreover, the frameless techniques and robotic features of the MKM enable a more surgeon- and patient-friendly stereotactic procedure.
为了使Mehrkoordinaten Manipulator（MKM）机器人导航系统能够用于无框架点立体定向手术，本文介绍了一种新的器械固定器。进行了一项基于体模的准确性研究，将这种新方法与使用Brown-Roberts-Wells（BRW）立体定向框架进行的基于框架的手术进行了比较。作者获取了一个测试体模的计算机断层扫描图像，该体模由一个圆形底座上的19根丙烯酸塑料靶棒组成。这些图像被用于基于框架（BRW）和无框架（MKM）的定位实验。在这两种情况下，作者都计算了实际靶点位置与立体定向到达位置之间的距离。使用BRW框架时，平均应用准确性（靶点配准误差）为0.68毫米，在手动重新定位显微镜后使用MKM系统时为0.96毫米（p<0.001）。仅使用机器人技术进行定位时显示出稍大的误差：1.47毫米（p<0.005）。由于外科医生关注的是个别病例中的最大误差而非大量病例中的平均误差，因此还比较了平均值+三个标准差。手动定位的MKM系统与BRW框架之间的该值差异很小（分别为2.04毫米和1.84毫米）。虽然使用BRW框架时每个靶点的重复性似乎稍好，但使用MKM系统时在体模体积上的准确性更均匀（两者差异均不显著）。总之，使用连接到系统的器械固定器进行的点立体定向手术的准确性与涉及立体定向框架的手术的准确性相当。此外，MKM的无框架技术和机器人特性使立体定向手术对外科医生和患者更友好。
