Emam T A, Hanna G, Cuschieri A
Department of Surgery and Molecular Oncology and Surgical Skills Unit, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, Scotland.
Surg Endosc. 2002 Mar;16(3):401-5. doi: 10.1007/s00464-001-8137-3. Epub 2001 Dec 17.
During complex laparoscopic operations, the surgeon often has to use both instruments to one side of the telescope (off-optical axis work). This experimental study was undertaken to compare this orthodox versus the off-optical axis endoscopic manipulations regarding the performance parameters and motion analysis and muscle work of the surgeon's dominant upper limb.
Ten surgeons participated in the study; each sutured 50-mm enterotomy in pig's small bowel in each of three setups: (1) in-optical axis manipulation (one instrument on either side of the laparoscope) (2) off-optical axis manipulation (both instruments on one side of the laparoscope to the dominant hand of the surgeon), and (3) off-optical axis manipulation both instruments on one side of the laparoscope on the nondominant side). The main outcome measures were the placement error score, execution time, leakage pressure, motion analysis, and telemetric electromyography parameters of the surgeon's dominant upper limb.
There was no significant difference in all parameters of performance, muscle work, and fatigue between setup 1 and setup 3. However, marked degradation of all parameters of performance with increased muscle work and fatigue was observed with setup 2 compared to setups 1 and 3. The reason for the deterioration with setup 2 is related to the altered "monitor display angle" which are different from the actual physical angles. With this setup, the instrument-to-target physical angle of 30 degrees appears on the screen as ?30 degrees and this disturbs both the manipulation and the azimuth angles obscuring the needle-tissue entry point. In addition, the instrument casts a shadow on its medial side and this tends to obscure the exact relations between instrument, needlepoint, and the tissue.
Off-optical axis work is a good alternative to the orthodox setup provided the instruments are placed to the nondominant hand. The marked degradation in performance encountered during off-optical axis work to the dominant hand of the surgeon is due to the resulting altered monitor display angles. The importance of these monitor display angles in influencing task performance has been previously overlooked.
在复杂的腹腔镜手术中，外科医生常常需要将双手器械都置于腹腔镜一侧（光轴外操作）。本实验研究旨在比较这种传统操作与光轴外内镜操作在性能参数、动作分析以及外科医生优势上肢肌肉工作方面的差异。
十名外科医生参与了该研究；每位医生在三种操作设置下分别对猪的小肠进行50毫米肠切开缝合：（1）光轴内操作（腹腔镜两侧各置一把器械）；（2）光轴外操作（两把器械均置于腹腔镜一侧且靠近外科医生优势手）；（3）光轴外操作（两把器械均置于腹腔镜一侧且靠近外科医生非优势手）。主要观察指标为放置误差评分、操作时间、漏液压力、动作分析以及外科医生优势上肢的遥测肌电图参数。
设置1和设置3在所有性能参数、肌肉工作及疲劳程度方面均无显著差异。然而，与设置1和设置3相比，设置2中随着肌肉工作及疲劳程度增加，所有性能参数均出现明显下降。设置2性能下降的原因与“监视器显示角度”改变有关，该角度与实际物理角度不同。在此设置下，30度的器械与目标物理角度在屏幕上显示为 -30度，这干扰了操作和方位角，使针与组织的进入点模糊不清。此外，器械在其内侧投下阴影，这往往会模糊器械、针尖与组织之间的确切关系。
倘若将器械置于非优势手，光轴外操作是传统操作的良好替代方法。外科医生优势手进行光轴外操作时性能显著下降是由于监视器显示角度改变所致。这些监视器显示角度对任务性能的影响此前一直被忽视。
