A surgical robot capable of reconnecting vessels with diameters as tiny as 0.3 millimetres has been tested on human patients, and the results are promising.
New research published in Nature Communications describes MUSA – the first robotic system designed exclusively for performing reconstructive supermicrosurgery. Using the system, surgeons were able to reconnect vessels with diameters between 0.3 and 0.8 millimetres, which, while not impossible for human surgeons, is a task that requires tremendous skill, dexterity, and patience. MUSA was recently tested on a small group of breast cancer patients, all of whom responded positively to the procedure, according to the paper.
The pilot trial involved 20 patients, all of whom were randomly selected for the study. All women in the trial had breast-cancer related lymphedema – a debilitating condition that can substantially reduce quality of life. Lymphedema can be treated with a microsurgical technique known as Lymphatico-venous anastomosis (LVA), in which highly skilled surgeons manually reconstruct and restore normal lymphatic flow and arterial circulation. But as the authors point out in the new study, “performance is limited by precision and dexterity of the human hands.” What’s more, not all patients qualify for LVA surgery, given its delicate nature.
Surgeons using MUSA. (Image: T. J. M. van Mulken et al., 2020)
With these limitations in mind, a team from Maastricht University Medical Centre, along with collaborators from Eindhoven University of Technology, both in The Netherlands, sought to assess the efficacy of robot-assisted reconstructive supermicrosurgery. Other robotic surgical platforms exist, such as the Da Vinci Robotic Surgical System, but none could be adapted to reconnect vessels at the microscale. This required the team to build a system specifically for the task.
MicroSure, the Netherlands-based company behind the platform, designed MUSA to be extremely stable; it’s capable of filtering out vibrations, or tremors, typically associated with the human hand. It also scales down motions made by the human surgeons who are in control of the system, making it easily manoeuvrable. MUSA has arms that hold microsurgical instruments and is compatible with standard surgical microscopes.
A pilot preclinical trial was set up to assess the system, in what is now the “first-in-human study of robot-assisted supermicrosurgery using a dedicated microsurgical robotic platform,” according to the paper, co-authored by Tom van Mulken from Maastricht University Medical Center.
Surgical outcomes were evaluated one and three months after surgery. The evaluators considered such factors as the quality of the connections and the length of time required for the surgery, both of which were compared to manual LVA surgery. The quality of the reconstructed vessels were very good and indistinguishable from manual LVA surgery, but full surgical time required for the robot-assisted group was 115 minutes, compared to the 81 minutes required for the manual group. The authors said that’s not a terrible discrepancy, noting that surgeons using the MUSA platform got faster as they overcame the steep learning curve and became more proficient with the controls.
No serious adverse outcomes were reported, and the quality of life in the patients improved, leading the authors to “report the feasibility of robot-assisted supermicrosurgical anastomosis in LVA, indicating promising results for the future of reconstructive supermicrosurgery.”
Looking ahead, the researchers would like to test the system on more patients and at other medical facilities. Surgeons are very skilled at what they do, but this robotic system could give them even more precision, while also potentially increasing the number of patients who can benefit from reconstructive supermicrosurgery.
Featured image: MicroSure