Maithel S K, Villegas L, Stylopoulos N, Dawson S, Jones D B
Department of Minimally Invasive Surgery, Beth Israel Deaconess Medical Center, 330 Brookline Ave, Boston, MA 02215, USA.
Surg Endosc. 2005 Mar;19(3):406-11. doi: 10.1007/s00464-004-8177-6. Epub 2004 Dec 23.
The direction of visual gaze may be an important ergonomic factor that affects operative performance. We designed a study to determine whether a head-mounted display (HMD) worn by the surgeon would improve task performance and/or reduce muscle fatigue during a laparoscopic task when compared to the use of a traditional video monitor display (VMD).
Surgical residents (n = 30) were enrolled in the study. A junior group, consisting of 15 postgraduate year (PGY) = 1 subjects with no previous laparoscopic experience, and a senior group, consisting of 15 PGY 4 and PGY 5 subjects with experience, completed a laparoscopic task that was repeated four times using the Computer Enhanced Laparoscopic Training System (CELTS). Groups alternated between using the HMD with the task placed in a downward frontal position and the VMD with the task at a 30 degrees lateral angle. The CELTS module assessed task completion time, depth perception, path length of instruments, response orientation, motion smoothness; the system then generated an overall score. Electromyography (EMG) was used to record sternocleidomastoid muscle activity. Display preference was surveyed.
The senior residents performed better than the junior residents overall on all parameters (p < 0.05) except for motion smoothness, where there was no difference. In both groups, the HMD significantly improved motion smoothness when compared to the VMD (p < 0.05). All other parameters were equal. There was less muscle fatigue when using the VMD (p < 0.05). We found that 66% of the junior residents but only 20% of the senior residents preferred the HMD.
The CELTS module demonstrated evidence of construct validity by differentiating the performances of junior and senior residents. By aligning the surgeon's visual gaze with the instruments, HMD improved smoothness of motion. Experienced residents preferred the traditional monitor display. Although the VMD produced less muscle fatigue, inexperienced residents preferred the HMD, possibly because of improved smoothness of motion.
视觉注视方向可能是影响手术操作性能的一个重要人体工程学因素。我们设计了一项研究，以确定与使用传统视频监视器显示屏（VMD）相比，外科医生佩戴的头戴式显示器（HMD）在腹腔镜手术任务期间是否会提高任务性能和/或减轻肌肉疲劳。
30名外科住院医师参与了该研究。一个初级组由15名没有腹腔镜手术经验的一年级研究生（PGY）组成，一个高级组由15名有经验的四年级和五年级PGY组成，他们使用计算机增强腹腔镜训练系统（CELTS）完成了一项重复四次的腹腔镜手术任务。两组在使用任务置于向下前方位置时的HMD和任务处于30度侧角时 的VMD之间交替。CELTS模块评估任务完成时间、深度感知、器械路径长度、反应方向、动作流畅性；然后系统生成一个总分。使用肌电图（EMG）记录胸锁乳突肌的活动情况。对显示器偏好进行了调查。
除动作流畅性无差异外，高级住院医师在所有参数上的总体表现均优于初级住院医师（p<0.05）。在两组中，与VMD相比HMD显著提高了动作流畅性（p<0.05）。所有其他参数相同。使用VMD时肌肉疲劳较少（p<0.05）。我们发现66%的初级住院医师但只有20%的高级住院医师更喜欢HMD。
CELTS模块通过区分初级和高级住院医师的表现证明了结构效度。通过使外科医生的视觉注视与器械对齐，HMD提高了动作的流畅性。有经验的住院医师更喜欢传统的监视器显示屏。虽然VMD产生的肌肉疲劳较少，但缺乏经验的住院医师更喜欢HMD，可能是因为动作流畅性有所提高。
