In our preclinical study, we conducted different surgeries on both sides of the same pig. This was done to ensure that the technical difficulty of the operations was comparable between the robotic and endoscopic groups.
The primary outcome was the total operative time, and we found no significant or clinically meaningful difference between the two groups. In fact, the total operative time in the robotic group was only approximately 6 min longer than that in the endoscopic group. Our result was in line with those reported by Dai and colleagues, who conducted a study involving twelve porcine models to compare KD-SR-01 robotic partial nephrectomy and laparoscopic partial nephrectomy.27 In their study, although the operative time in the robotic group was 11 min longer than that in laparoscopic group, they also found no significant difference between the two groups. Notably, when we removed the docking time in our study, the time required for surgical procedures was almost identical between the robotic and endoscopic groups. As demonstrated as the above findings, operative times were not necessarily prolonged when using this newly-developed surgical robotic platform in porcine models. However, in real-world clinical settings, it remains uncertain whether robotic surgery can match the surgical duration of conventional procedures.28–30 Kim et al.31 posited that extensive training can markedly decrease the duration of robotic surgeries. Their research demonstrated significant reductions in the average operation time associated with robot-assisted neck dissections as experience accumulated. One study even revealed that, with extensive training of the robot, surgical duration could be reduced by up to 40%.32
Modern robotic surgery comes highly recommended not only for its efficiency but, more importantly, for its potential to enhance aesthetic outcomes, improve bleeding control, and minimize complications, among other benefits33,34. Given the extensive blood flow in the head and neck region, effective bleeding control and maintaining a clear surgical field are crucial aspects of robotic surgery. Lim et al. observed notably lower estimated blood loss using da Vinci system, especially in complex cases like post-styloid parapharyngeal space tumors.35 Although it has not been used in human head and neck surgery, the newly-developed surgical robot could compare with the da Vinci robot in terms of bleeding control in colonic surgeries.24 Our results demonstrated that this system was also well in control bleeding in head and neck surgery. This enhancement in blood loss control can be attributed to the sophisticated capabilities of robotic systems, which encompass features such as tremor reduction, 3D imaging, and surgical instruments with a wider range of motion. These attributes collectively empower surgeons to more accurately identify and dissect blood vessels within the correct anatomical planes, thereby leading to a reduction in intraoperative bleeding. However, it is worth noting that in our study, during submandibular gland resection, we did not observe statistically significant differences in estimated blood loss between the two groups. This can be attributed to the distinct anatomical characteristics of the porcine submandibular gland, which possesses a well-defined boundary with the surrounding tissue and relatively fewer blood vessels in proximity. Besides bleeding control, the protection of critical nerves is also very important for some head and neck surgeries.36–38 IFNM was utilized and the results demonstrated that facial nerve was protected well during operations.
However, these experimental findings do not directly establish that the robot can produce similar results in humans, primarily due to the anatomic disparities between humans and pigs. Firstly, while the parotid gland of pig is larger, it lacks the precise blood vessels and main facial nerve running through it, making parotid gland removal in pigs comparatively easier. In humans, the parotid gland contains many blood vessels and features a more intricate facial nerve structure, which heightens the complexity of the surgery. Secondly, the submandibular gland in pigs features a denser envelope and presents a well-defined boundary with the surrounding blood vessels. Thirdly, the larger lower jaw in pigs, in comparison to that of adult humans, results in a greater distance for the surgical instruments to traverse from behind the pig's ear to the leading edge of the parotid gland and the lower boundary of the neck. This extended distance also contributes to the heightened surgical complexity. These dissimilarities underscore the necessity of conducting robotic clinical trials to bridge the gap between animal models and human applications.
In the realm of surgical robots, comparisons between the newly-developed surgical robotic system and the da Vinci system are inevitable. Regarding postoperative outcomes, Li et al. conducted a comparative study on robot-assisted partial nephrectomy (RAPN), a common and representative procedure, to assess these two systems.39 Their study, comprising 99 RAPN surgeries (49 with KD-SR and 50 with da Vinci), indicated that the KD-SR achieved efficacy comparable to the da Vinci robot, with no significant differences in complication rates between the groups. Additionally, Fan’s study on robot-assisted radical prostatectomy (RARP) using the KD-SR also reported similar short-term oncological and functional outcomes, albeit with a longer operation duration compared to the da Vinci system.40 They suggested that the operational efficiency of the KD-SR might be enhanced through more comprehensive training, as evidenced by their extensive experience gained form over 400 RARP cases with the da Vinci system. In addition to its successful application in urological surgeries, the KD-SR-01 is as effective as the da Vinci system for colon cancer procedures.24 The performance of the KD-SR-01 in these procedures therefore raises expectations for its application in head and neck surgeries.
The KD-SR-01 system distinguishes itself from the da Vinci in several design aspects. Firstly, its open visual console, unlike da Vinci's immersive setup, enables surgeons to maintain a natural posture, reducing neck stiffness during prolonged surgeries and enhancing interaction with the assisting team. Secondly, the KD-SR's arm configuration also differs. It features grouped arms mounted on a rotatable boom, facilitating easier patient positioning adjustments compared to da Vinci's independent arms25. Anticipated future advancements for the this newly-developed surgical robotic system includes enhanced imaging with fluorescence, fully independent arm movements, real-time haptic feedback, and the development of single-port arms. These improvements aim to enhance surgical precision, control, and expand the range of possible surgeries. Cost-effectiveness is another crucial distinction. The KD-SR’s development and production costs are estimated to be only 25%-30% of those for the da Vinci,41 making it a more accessible option for budget-conscious medical facilities. This affordability could lead to its wider adoption and increased accessibility for robotic-assisted surgeries, benefiting a broader range of patients.
This study had some limitations that need to be considered. Firstly, the extrapolation of our results from preclinical models to human application may be limited due to inter-species differences.42 As such, the necessity for further clinical trials is evident, and we are actively working to promote such trials to bridge the gap between preclinical and clinical settings. Secondly, in our effort to assess the potential applicability of the KD-SR-01 in head and neck surgery, we conducted three distinct procedures. This approach, while informative, resulted in relatively small sample sizes for each procedure due to budget constraints. Lastly, when evaluating the KD-SR-01, it is worth noting that comparing it with established platforms like the da Vince system may provide a more objective assessment. Such comparisons can offer insights into the strengths and weaknesses of the new system in relation to exiting technologies.
This newly-developed oral and maxillofacial surgical robotic system has preliminarily demonstrated its technical feasibility, safety, and validity in head and neck surgery. This innovative system offers distinct advantages from an ergonomic perspective, particularly when compared to traditional endoscopic surgery. Despite the promising potential of KD-SR-01, it is imperative to underscore the necessity for a meticulously designed clinical trial, inclusive of an extensive follow-up period. This would be pivotal in rigorously evaluating the true efficacy and utility of the KD-SR-01. Conducting such a comprehensive study is essential to gain a holistic understanding of the system's strengths and limitations within a clinical environment.