Learning Curve and Ergonomics Associated with the 3D-monitor-assisted Microsurgery Using a Digital Microscope.

Objectives: The use of three-dimensional monitors and digital microscopes for microsurgery is becoming prevalent and has great expectations of providing ergonomic advantages for surgeons. However, it remains unclear if this approach does provide ergonomic benefits, and whether transitional difficulties will be encountered when using it in place of a conventional optical microscope. Therefore, the purpose of this study was to clarify both the subjective and objective ergonomic advantages and the learning curve associated with the use of a digital microscope. Methods: Seventeen cases of head and neck reconstruction using a digital microscope were compared with those using a conventional optical microscope with respect to the time required for vascular anastomoses, microvascular complications, and ergonomics of the surgeon. The surgeons' learning curve was evaluated by comparing the time required for the transitions during the vascular anastomoses in each series. An objective ergonomics study was conducted by evaluating muscle fatigue using electromyography (EMG) during simulated vascular anastomosis. Results: The time required for vascular anastomosis transitions using a digital microscope gradually decreased in a linear fashion. In the objective study to check muscle fatigue by using EMG, a digital microscope was found to provide an ergonomic advantage for surgeons in the lower trapezius muscle part as compared to a conventional optical microscope. Conclusions: At present, a digital microscope provides modest ergonomic benefits to surgeons and requires a certain amount of time to learn.