Strauss Gero, Koulechov Kirill, Hofer Mathias, Dittrich Elmar, Grunert Ronny, Moeckel Hendrick, Müller Eva, Korb Werner, Trantakis Christos, Schulz Thomas, Meixensberger Juergen, Dietz Andreas, Lueth Tim
Department of ENT, University Hospital Leipzig, Leipzig, Germany.
Laryngoscope. 2007 Mar;117(3):434-41. doi: 10.1097/MLG.0b013e31802c93a1.
This study examines the feasibility of a navigation-controlled (NC) drill for surgery on the petrosal bone in an experimental environment. According to the principle of NC, the drill is to be switched off automatically once the borders of the workspace are exceeded during a mastoidectomy.
The registration is based on an optical navigation system with navigation software (MiMed). As surgery engine, the Unidrive-system (Karl Storz GmbH & CO. Kg, Tuttlingen, Germany) was integrated. The definition of the workspace was performed manually in axial computed tomography (CT) slices of the petrosal bone phantom. The mastoidectomy on the model was accomplished in three runs with 10 trial surgeons altogether (5 experienced [exp.] in otologic (ear) surgery, 5 inexperienced [nonexp.]). During each run, the following were logged: the total length of time for the procedure as well as the number and extent of injuries to the risk structures (facial nerve, horizontal semicircular canal, sigmoid sinus). The resultant petrosal bone cavities were measured on the CT.
The time for the segmentation of the workspace for the mastoidectomy amounted to 17 minutes. The mean value of the drilling (e.g., milling) performance ranges from 6.61 mm3/s (group 1 [nonexp. + NC]), 9.62 mm3/s (group 2 [exp. w/o NC]), to 10.08 mm3/s (group 3 [exp. + NC]). The relative deviation to the segmented volume amounts to +7.4% (794.3 mm3) for group 1, -39.9% for group 2, and -34% (3,647.0 mm3) for group 3. In the groups with NC guidance of the drill, no damage to a risk structure could be logged. In the group of exp. ear surgeons without NC assistance, one injury to the facial nerve in the petrosal bone phantom occurred.
The results that follow prove the fundamental feasibility of an NC drill for surgery of the petrosal bone using the example of the simple mastoidectomy in the laboratory test. When using NC, tissue resection is faster, more precise, and has fewer related complications than the same procedure without. The results offer a very promising basis for the introduction of a newly conceived system to the procedure of NC surgery on the petrosal bone. The device configuration used here was originally conceived for NC guidance of a shaver in functional endoscopic sinus surgery. Individual errors will have to be mitigated through the new version of the control unit presently in development.
本研究在实验环境中检验了用于颞骨手术的导航控制（NC）钻的可行性。根据NC原理，在乳突切除术中一旦超出工作空间边界，钻头将自动关闭。
配准基于带有导航软件（MiMed）的光学导航系统。作为手术引擎，集成了Unidrive系统（卡尔史托斯有限公司，德国图特林根）。在颞骨模型的轴向计算机断层扫描（CT）切片上手动定义工作空间。对模型进行了三次乳突切除术，共有10名试验外科医生参与（5名有经验的[exp.]耳科（耳部）手术医生，5名无经验的[nonexp.]）。在每次手术过程中，记录以下内容：手术总时长以及对危险结构（面神经、水平半规管、乙状窦）的损伤数量和程度。在CT上测量所得的颞骨腔。
乳突切除术工作空间的分割时间为17分钟。钻孔（如铣削）性能的平均值范围为6.61立方毫米/秒（第1组[无经验+NC]）、9.62立方毫米/秒（第2组[有经验但无NC]）至10.08立方毫米/秒（第3组[有经验+NC]）。与分割体积的相对偏差在第1组中为+7.4%（794.3立方毫米），第2组为-39.9%，第3组为-34%（3647.0立方毫米）。在钻头有NC引导的组中，未记录到对危险结构的损伤。在无NC辅助的有经验耳科医生组中，在颞骨模型上发生了1例面神经损伤。
后续结果以实验室测试中简单乳突切除术为例，证明了NC钻用于颞骨手术的基本可行性。使用NC时，组织切除比无NC时更快、更精确且相关并发症更少。这些结果为将一种新构思的系统引入颞骨NC手术过程提供了非常有前景的基础。这里使用的设备配置最初是为功能性内窥镜鼻窦手术中剃须刀的NC引导而设计的。个别误差将必须通过目前正在开发的新版本控制单元来减轻。
