The Hamlyn Centre for Robotic Surgery, Imperial College London, Bessemer Building, B411 Level 4, South Kensington Campus, London SW7 2AZ, United Kingdom.
Int J Surg. 2012;10(2):80-6. doi: 10.1016/j.ijsu.2011.12.005. Epub 2011 Dec 28.
To characterise navigational patterns in the abdominal cavity associated with different spatial awareness status of the operator during navigation of Natural Orifice Transluminal Endoscopic Surgery (NOTES). It is hypothesised that poor spatial awareness will manifest as erratic navigational patterns and poor performance.
Ten endoscopic novices navigated a defined course in a NOTES phantom (NOSsE) simulating the path of peritoneoscopic examination. Subjects performed the task three times without and once with an additional laparoscopic camera. Electromagnetic tracking was used to trace the tip of the endoscope during the navigation. Metrics of performance included the number of correctly visualised course targets, between targets localisation time and path length, and total completion time. Spatial awareness was explored by means of topological modelling of the navigation trace. Spatial navigation maps were generated from the tip trace footprint, differentiated using the Earth Movers Distance (EMD) and captured in a two dimensional chart where proximity in the projected space reflects similarity of navigation behaviour. Groups were identified displaying idiosyncratic target to target transitions in endoscopic navigation behaviour.
No significant differences were found between four sessions in terms of the path length. Time was statistically improved when using supplemental visualisation (p<0.05). Four awareness groups were identified based on the subjects exhibited navigation footprint over the frontal plane, namely: (1) consistent navigation and performance; (2) inconsistent navigation and performance; (3) improvements in navigation and performance despite undifferentiated behavioural signatures; and (4) inconsistent navigation with improvements in performance.
Tracking the tip of the endoscope permits reconstruction of the navigation path during extraluminal navigation. The spatial location of the tip of the endoscope during navigation was used to unveil the operator's spatial awareness. Navigation routes in this study have been projected onto a 2D scene, related to performance and classified according to exhibited spatial awareness. Our assessment of this relationship suggests that poor spatial awareness is accompanied by erratic manoeuvres, often leading to poor performances, and vice versa. Tracking the location of the tip of the endoscope is an important issue in NOTES, and similarly understanding the spatial awareness of the operator is crucial in terms of the safety in NOTES. This work may have significant implications for training and assessment of new NOTES or minimally invasive surgeons. It may also lead to the new designs of endoscopes for NOTES.
描述在自然腔道内镜手术（NOTES）中，由于操作者空间感知状态的不同，在腹腔内导航时的导航模式。假设空间感知能力差会表现为导航模式不稳定和表现不佳。
10 名内镜新手在 NOTES 模拟体（NOSsE）中导航一条定义的路径，模拟腹膜检查的路径。受试者在没有和有额外腹腔镜摄像头的情况下各完成 3 次任务。电磁跟踪用于跟踪导航过程中内窥镜的尖端。性能指标包括正确可视化的课程目标数量、目标之间的定位时间和路径长度以及总完成时间。空间意识通过导航轨迹的拓扑建模来探索。从尖端轨迹足迹生成空间导航图，使用大地移动距离（EMD）进行区分，并在二维图表中捕获，其中在投影空间中的接近度反映了导航行为的相似性。在识别出具有独特目标到目标转换的内镜导航行为时，将这些组进行了区分。
在路径长度方面，四次试验之间没有显著差异。使用补充可视化时，时间有统计学上的改善（p<0.05）。根据受试者在额状面上表现出的导航足迹，确定了四个意识组，分别为：（1）一致的导航和表现；（2）不一致的导航和表现；（3）尽管行为特征没有差异，但导航和表现都有所改善；（4）导航不一致但表现改善。
跟踪内窥镜的尖端允许重建腔外导航期间的导航路径。导航过程中内窥镜尖端的空间位置用于揭示操作者的空间感知。在这项研究中，导航路线被投射到一个二维场景中，与性能相关，并根据表现出的空间感知进行分类。我们对这种关系的评估表明，空间感知能力差伴随着不稳定的操作，通常导致表现不佳，反之亦然。跟踪内窥镜尖端的位置在 NOTES 中是一个重要问题，同样，理解操作者的空间感知在 NOTES 的安全性方面也至关重要。这项工作可能对新的 NOTES 或微创手术医生的培训和评估具有重要意义。它也可能导致 NOTES 用内窥镜的新设计。
