Robotic and robot-assisted skull base neurosurgery: systematic review of current applications and future directions

OBJECTIVE The utility of robotic instrumentation is expanding in neurosurgery. Despite this, successful examples of robotic implementation for endoscopic endonasal or skull base neurosurgery remain limited. Therefore, the authors performed a systematic review of the literature to identify all articles that used robotic systems to access the sella or anterior, middle, or posterior cranial fossae. METHODS A systematic review of MEDLINE and PubMed in accordance with PRISMA guidelines performed for articles published between January 1, 1990, and August 1, 2021, was conducted to identify all robotic systems (autonomous, semiautonomous, or surgeon-controlled) used for skull base neurosurgical procedures. Cadaveric and human clinical studies were included. Studies with exclusively otorhinolaryngological applications or using robotic microscopes were excluded. RESULTS A total of 561 studies were identified from the initial search, of which 22 were included following full-text review. Transoral robotic surgery (TORS) using the da Vinci Surgical System was the most widely reported system (4 studies) utilized for skull base and pituitary fossa procedures; additionally, it has been reported for resection of sellar masses in 4 patients. Seven cadaveric studies used the da Vinci Surgical System to access the skull base using alternative, non–TORS approaches (e.g., transnasal, transmaxillary, and supraorbital). Five cadaveric studies investigated alternative systems to access the skull base. Six studies investigated the use of robotic endoscope holders. Advantages to robotic applications in skull base neurosurgery included improved lighting and 3D visualization, replication of more traditional gesture-based movements, and the ability for dexterous movements ordinarily constrained by small operative corridors. Limitations included the size and angulation capacity of the robot, lack of drilling components preventing fully robotic procedures, and cost. Robotic endoscope holders may have been particularly advantageous when the use of a surgical assistant or second surgeon was limited. CONCLUSIONS Robotic skull base neurosurgery has been growing in popularity and feasibility, but significant limitations remain. While robotic systems seem to have allowed for greater maneuverability and 3D visualization, their size and lack of neurosurgery-specific tools have continued to prevent widespread adoption into current practice. The next generation of robotic technologies should prioritize overcoming these limitations.

Hybrid Robotics for Endoscopic Transnasal Skull Base Surgery: Single-Centre Case Series

BACKGROUND Only preclinical studies and case reports have described robotic surgery for endoscopic transnasal skull base surgery. OBJECTIVE To evaluate the role of a novel robotic endoscope holder, developed for transsphenoidal surgery. METHODS Patients were prospectively enrolled for 3 mo at the Neurosurgery Unit of Brescia. Endoscope Robot® was used to assist during the sphenoidal phase of the approach, tumor removal, and skull base reconstruction. A Likert scale questionnaire was given to all surgeons after each procedure. Patients who underwent robotic-assisted surgery were matched with nonrobotic ones for pathology and type of procedure. All surgical videos were evaluated during bimanual phases. RESULTS Twenty-one patients underwent robot-assisted, endoscopic transsphenoidal surgery for different pathologies (16 pituitary adenomas, 3 chordomas, 1 craniopharyngioma, 1 pituitary exploration for Cushing disease) for a total of 23 procedures (1 patient underwent 2 endoscopic revisions of a skull base reconstruction). Subjective advantages reported by surgeons included smoothness of movement, image steadiness, and improvement of maneuvers in narrow spaces and with angled endoscopes; as the main limitation, Endoscope Robot® appeared to be relatively heavy during the initial endoscope positioning. A comparative analysis with a historical matched cohort documented similar clinical outcomes, while endoscope lens cleaning and position readjustments were significantly less frequent in robotic procedures. CONCLUSION Although confirmation in larger studies is needed, Endoscope Robot® was a safe and effective tool, especially advantageous in lengthy interventions through deep and narrow corridors.

Safe Human-Robot Interaction Using Variable Stiffness, Hyper-Redundancy, and Smart Robotic Skins

In service robotics, safe human-robot interaction (HRI) is still an open research topic, requiring developments both in hardware and in software as well as their integration. In UMAY1 and MEDICARE-C2projects, we addressed both mechanism design and perception aspects of a framework for safe HRI. Our first focus was to design variable stiffness joints for the robotic neck and arm to enable inherent compliance to protect a human collaborator. We demonstrate the advantages of variable stiffness actuators (VSA) in compliancy, safety, and energy efficiency with applications in exoskeleton and rehabilitation robotics. The variable-stiffness robotic neck mechanism was later scaled down and adopted in the robotic endoscope featuring hyper-redundancy. The hyper-redundant structures are more controllable, having efficient actuation and better feedback. Lastly, a smart robotic skin is introduced to explain the safety support via enhancement of tactile perception. Although it is developed for a hyper-redundant endoscopic robotic platform, the artificial skin can also be integrated in service robotics to provide multimodal tactile feedback. This chapter gives an overview of systems and their integration to attain a safer HRI. We follow a holistic approach for inherent compliancy via mechanism design (i.e., variable stiffness), precise control (i.e., hyper-redundancy), and multimodal tactile perception (i.e., smart robotic-skins).