Introduction
With the exploration of increasingly less invasive surgical techniques, such as single incision or natural orifice surgery, numerous technical challenges have been identified as essential to be overcome if the techniques are to be adopted across the wider surgical community. One of the most significant includes; impaired visualisation of the operative site. For single incision approaches in particular, the restricted workspace, related to the close proximity of the other instruments, results in difficulties manoeuvring the rigid laparoscope for view optimisation. This abstract introduces a novel hyper-redundant flexible robotic laparoscope which imparts 5 degrees of freedom at its distal tip enabling mounted cameras to provide the surgeon with essential and stable, off-axis views of the operating field whilst ensuring the laparoscope shaft is out of the way of the other instruments. The study explores the controllability of the device in a simulated and live in-vivo porcine model using time and motion analysis of the remote operating control to assess usability.
Methods
The task required each subject to control the robotic laparoscope to visualise a set of targets sequentially. In both environments the targets were placed in the upper abdomen and the robot clamped externally to ensure that visualisation of the targets was solely achieved through the control of the robot’s three distal joints and the on-board cameras. The targets were placed at locations which challenged the range of motion of each joint, with the greatest linear distance between any two targets being 23cm.
Seven novice subjects performed three trials in the simulated environment and a separate four subjects, performed five trials within a live 70Kg porcine model. Within this setting a pneumo-peritoneum using CO2 insufflation was initially established with pressure maintained at 12mmHg. A 15mm trocar was inserted infra-umbilical to accommodate the robotic instrument. A user interface device was positioned remotely from the robot but within the operating theatre.
Results
In both the simulator and live in-vivo models the robotic instrument enabled each target to be visualised without the need to manipulate the device externally, with the time to completion ranging from 37 – 166.3s (mean 71.8s) in the simulator and 28.9 – 74s (mean 51.8s) in-vivo. The number of movements of the operating control needed to complete the task ranged from 21 – 96 (median 58) and 15 – 67 (median 44) respectively. A significant reduction in time taken and the number of motions required to complete the task was demonstrated between the first and last run performed in the simulator (p=0.026, p=0.011) indicating that each subject was not simply moving the controller faster but controlling the instrument more efficiently (Fig 1 (c))
Conclusion
This demonstrates a clinically usable instrument within the setting of minimally invasive surgery offering not only the flexibility to optimise the operative view but also the capacity to deliver many of the benefits associated with a computer enhanced platform.
Figure 1; The flexible robotic laparoscope (a) demonstrated in the live in-vivo model (b) and the simulator with results from the usability trial (c, d).
Session: Poster
Program Number: P561
