Purpose

3D-printed cutting guides are the current standard to translate the virtual surgery plan to the intraoperative setting. The production of these patient-specific cutting guides is time-consuming and costly, and therefore, alternative approaches are currently subject of research. The aim of this study was to assess the accuracy and reproducibility of using a novel electromagnetic (EM) navigated surgical cutting guide to perform virtually planned osteotomies in mandible models.

Methods

A novel 3D navigated cutting guide (dubbed Bladerunner) was designed and evaluated with a total of 20 osteotomies, performed on plaster mandibular models according to preoperative planning using EM navigation. The pre- and postoperative scans were registered, and the difference between the preoperatively planned osteotomy and the performed osteotomy was expressed as the distance between the planned and performed cutting planes, and the yaw and roll angles between the planes.

Results

The mean difference in distance between the planned osteotomy and performed osteotomy was 1.1 mm (STD 0.6 mm), the mean yaw was 1.8° (STD 1.4°), and mean roll was 1.6° (STD 1.3°).

Conclusion

The proposed EM navigated cutting guide for mandibular osteotomies demonstrated accurate positioning of the cutting plane according to the preoperative virtual surgical plan with respect to distance, yaw and roll angles. This novel approach has the potential to make the use of 3D-printed cutting guides obsolete, thereby decreasing the interval between diagnosis and surgery, reduce cost and allow for adaptation of the virtual plan in case of rapid tumor proliferation or unanticipated in situ deviations from the preoperative CT/MR imaging.

中文翻译：

---

下颌骨截骨术的外科导航切割指南：图像引导下颌骨截骨术的准确性和可重复性。

目的

3D打印的切割指南是将虚拟手术计划转换为术中设置的当前标准。这些针对患者的切割指南的生产既耗时又昂贵，因此，替代方法目前是研究的主题。这项研究的目的是评估使用新颖的电磁（EM）导航手术切割指南在下颌骨模型中进行虚拟计划的切骨术的准确性和可重复性。

方法

设计了一种新颖的3D导航切割向导（称为Bladerunner），并根据EM导航的术前计划，对石膏下颌模型进行了总共20处截骨术的评估。记录术前和术后扫描，术前计划的截骨术与进行的截骨术之间的差异表示为计划的和执行的切割平面之间的距离以及平面之间的偏航角和横滚角。

结果

计划的截骨术与进行的截骨术之间的平均距离差为1.1毫米（STD 0.6毫米），平均偏航为1.8度（STD 1.4度），平均侧倾为1.6度（STD 1.3度）。

结论

拟议的用于下颌骨截骨术的EM导航切割指南证明了根据术前虚拟手术计划相对于距离，偏航角和侧倾角对切割平面的精确定位。这种新颖的方法有可能过时地使用3D打印的切割指南，从而缩短诊断和手术之间的时间间隔，降低成本，并在肿瘤快速扩散或原位预料不到的情况下允许对虚拟计划进行调整。术前CT / MR成像。