Magnetic tracking in the operation room using the da Vinci(®) telemanipulator is feasible

The influence of the da Vinci surgical robot on electromagnetic tracking in a clinical environment

Robot-assisted surgery is increasingly used in surgery for cancer. Reduced overview and loss of anatomical orientation are challenges that might be solved with image-guided surgical navigation using electromagnetic tracking (EMT). However, the robot's presence may distort the electromagnetic field, affecting EMT accuracy. The aim of this study was to evaluate the robot's influence on EMT accuracy. For this purpose, two different electromagnetic field generators were used inside a clinical surgical environment: a table top field generator (TTFG) and a planar field generator (PFG). The position and orientation of sensors within the electromagnetic field were measured using an accurate in-house developed 3D board. Baseline accuracy was measured without the robot, followed by stepwise introduction of potential distortion sources (robot and robotic instruments). The absolute accuracy was determined within the entire 3D board and in the clinical working volume. For the baseline setup, median errors in the entire tracking volume within the 3D board were 0.9 mm and 0.3° (TTFG), and 1.1 mm and 0.4° (PFG). Adding the robot and instruments did not affect the TTFG's position accuracy (p = 0.60), while the PFG's accuracies decreased to 1.5 mm and 0.7° (p < 0.001). For both field generators, when adding robot and instruments, accuracies inside the clinical working volume were higher compared to the entire tracking 3D board volume, 0.7 mm and 0.3° (TTFG), and 1.1 mm and 0.7° (PFG). Introduction of a surgical robot and robotic instruments shows limited distortion of the EMT field, allowing sufficient accuracy for surgical navigation in robotic procedures.

[Status Quo of Surgical Navigation]

Surgical navigation, also referred to as computer-assisted or image-guided surgery, is a technique that employs a variety of methods - such as 3D imaging, tracking systems, specialised software, and robotics to support surgeons during surgical interventions. These emerging technologies aim not only to enhance the accuracy and precision of surgical procedures, but also to enable less invasive approaches, with the objective of reducing complications and improving operative outcomes for patients. By harnessing the integration of emerging digital technologies, surgical navigation holds the promise of assisting complex procedures across various medical disciplines. In recent years, the field of surgical navigation has witnessed significant advances. Abdominal surgical navigation, particularly endoscopy, laparoscopic, and robot-assisted surgery, is currently undergoing a phase of rapid evolution. Emphases include image-guided navigation, instrument tracking, and the potential integration of augmented and mixed reality (AR, MR). This article will comprehensively delve into the latest developments in surgical navigation, spanning state-of-the-art intraoperative technologies like hyperspectral and fluorescent imaging, to the integration of preoperative radiological imaging within the intraoperative setting.

Real-Time Multi-Modal Sensing and Feedback for Catheterization in Porcine Tissue

Objective: In this study, we introduce a multi-modal sensing and feedback framework aimed at assisting clinicians during endovascular surgeries and catheterization procedures. This framework utilizes state-of-the-art imaging and sensing sub-systems to produce a 3D visualization of an endovascular catheter and surrounding vasculature without the need for intra-operative X-rays. Methods: The catheterization experiments within this study are conducted inside a porcine limb undergoing motions. A hybrid position-force controller of a robotically-actuated ultrasound (US) transducer for uneven porcine tissue surfaces is introduced. The tissue, vasculature, and catheter are visualized by integrated real-time US images, 3D surface imaging, and Fiber Bragg Grating (FBG) sensors. Results: During externally-induced limb motions, the vasculature and catheter can be reliably reconstructed at mean accuracies of 1.9±0.3 mm and 0.82±0.21 mm, respectively. Conclusions: The conventional use of intra-operative X-ray imaging to visualize instruments and vasculature in the human body can be reduced by employing improved diagnostic technologies that do not operate via ionizing radiation or nephrotoxic contrast agents. Significance: The presented multi-modal framework enables the radiation-free and accurate reconstruction of significant tissues and instruments involved in catheterization procedures.

Robotic-assisted stereotactic real-time navigation: initial clinical experience and feasibility for rectal cancer surgery

BACKGROUND

Real-time stereotactic navigation for transanal total mesorectal excision has been demonstrated to be feasible in small pilot series using laparoscopic techniques. The possibility of real-time stereotactic navigation coupled with robotics has not been previously explored in a clinical setting.

METHODS

After pre-clinical assessment, and configuration of a robotic-assisted navigational system, two patients with locally advanced rectal cancer were selected for enrollment into a pilot study designed to assess the feasibility of navigation coupled with the robotic da Vinci Xi platform via TilePro interface. In one case, fluorescence-guided surgery was also used as an adjunct for structure localization, with local administration of indocyanine green into the ureters and at the tumor site.

RESULTS

Each operation was successfully completed with a robotic-assisted approach; image-guided navigation provided computed accuracy of ± 4.5 to 4.6 mm. The principle limitation encountered was navigation signal dropout due to temporary loss of direct line-of-sight with the navigational system's infrared camera. Subjectively, the aid of navigation assisted the operating surgeon in identifying critical anatomical planes. The combination of fluorescence with image-guided surgery further augmented the surgeon's perception of the operative field.

CONCLUSIONS

The combination of stereotactic navigation and robotic surgery is feasible, although some limitations and technical challenges were observed. For complex surgery, the addition of navigation to robotics can improve surgical precision. This will likely represent the next step in the evolution of robotics and in the development of digital surgery.

Objective Assessment of the Early Stages of the Learning Curve for the Senhance Surgical Robotic System

OBJECTIVE

The purpose of this research is to study the early stages of the Senhance learning curve to report how force feedback impacts learning rate. This serves as an exploratory investigation into assumptions that fellows and faculty will adjust faster to the Senhance in comparison with residents, and that force feedback will not hinder skill acquisition.

DESIGN

In this study, participants completed the peg transfer and precision cutting task from the Fundamentals of Laparoscopic Surgery (FLS) manual skills assessment five times each using the Senhance while instrument motion was tracked.

SETTING

This study took place in the Surgical Education and Activities Laboratory at Duke University Medical Center.

PARTICIPANTS

Participants for this study were residents, fellows, and faculty from Duke University Medical Center in general surgery and gynecology specialties (N = 16).

RESULTS

Postulated linear mixed effects models with participant level random effects showed significant improvement with additional attempts for the peg transfer task after adjusting for surgical experience and force feedback respectively for the primary FLS score metric. The secondary metric of total instrument path length also showed improvement (significant decreases) in path length with additional attempts after respectively adjusting for surgical experience and force feedback.

CONCLUSIONS

This study investigates the early stages of the learning curve of the Senhance. Exploratory modeling indicates that residents, fellows, and faculty surgeons rapidly adapt to the controls of the Senhance regardless of experience level and force feedback engagement. The results from this study may serve as motivation for future prospective studies that achieve sufficient statistical power with a larger sample size and strict experimental design.

Dynamics of a magnetically rotated micro swimmer inspired by paramecium metachronal wave

In the past few years, a significant body of research has been devoted to designing magnetic micron scale robotic systems for minimally invasive medicine. The motion of different microorganisms is the nature's solution for efficient propulsion of these swimmers. So far, there has been a considerable effort in designing micro swimmers based on the propulsion of bacteria while the motion of numerous other microorganisms has not been a source of inspiration for designing micro swimmers yet. Inspired by propulsion of Paramecium which is a ciliate microorganism, a novel micro swimmer is proposed in this article which is capable of cargo transport. This novel swimmer is composed of multiple equally spaced rigid loxodromic rods spanning the surface of a sphere which can carry a cargo placed inside it. The propulsion of this swimmer is influenced by the geometry of the swimmer (diameter, number of rods, cargo size), therefore, CFD simulations have been performed to investigate it. Finally, the dynamics of this swimmer is investigated analytically which sheds light into the complex dynamics of a swimmer with this geometry.

Navigation of a robot-integrated fluorescence laparoscope in preoperative SPECT/CT and intraoperative freehand SPECT imaging data: a phantom study

Robot-assisted laparoscopic surgery is becoming an established technique for prostatectomy and is increasingly being explored for other types of cancer. Linking intraoperative imaging techniques, such as fluorescence guidance, with the three-dimensional insights provided by preoperative imaging remains a challenge. Navigation technologies may provide a solution, especially when directly linked to both the robotic setup and the fluorescence laparoscope. We evaluated the feasibility of such a setup. Preoperative single-photon emission computed tomography/X-ray computed tomography (SPECT/CT) or intraoperative freehand SPECT (fhSPECT) scans were used to navigate an optically tracked robot-integrated fluorescence laparoscope via an augmented reality overlay in the laparoscopic video feed. The navigation accuracy was evaluated in soft tissue phantoms, followed by studies in a human-like torso phantom. Navigation accuracies found for SPECT/CT-based navigation were 2.25 mm (coronal) and 2.08 mm (sagittal). For fhSPECT-based navigation, these were 1.92 mm (coronal) and 2.83 mm (sagittal). All errors remained below the <1-cm detection limit for fluorescence imaging, allowing refinement of the navigation process using fluorescence findings. The phantom experiments performed suggest that SPECT-based navigation of the robot-integrated fluorescence laparoscope is feasible and may aid fluorescence-guided surgery procedures.

Design of Virtual Fixtures for Robotic Cholecystectomy

BACKGROUND AND OBJECTIVE

With the ongoing developments in robotic surgery, the associated adverse events need to be carefully evaluated. Virtual fixtures (VFs), a safety design feature against unintended motion during robotic surgery, have been proposed, but the methodology for designing VFs remains experimental. In this study, we propose a novel methodology for designing VFs for robotic cholecystectomy.

MATERIALS AND METHODS

Laparoscopic cholecystectomy (LC) was performed in 24 patients with cholecystitis. Active working space (AWS), the distance between instrument heads (DBIH), motion speed of bilateral hands, and instrument heads were calculated and analyzed.

RESULTS

DBIH was 14.78 ± 6.94 cm. Diameter of right and left AWS was 15.81 ± 3.69 cm and 15.33 ± 1.52 cm, respectively. DBIH was found to significantly correlate with the surgeon's experience. Bilateral AWS was found to be significantly associated with body circumference at Murphy's point level. However, no association was observed between bilateral AWS and surgeon's experience.

CONCLUSIONS

A novel methodology to build VFs for designing VFs for robotic cholecystectomy is established. Surgeon's experience appears to play an important role in determining the DBIH during robotic laparoscopic cholecystectomy, but does not affect bilateral AWS.

Real-time image guidance in laparoscopic liver surgery: first clinical experience with a guidance system based on intraoperative CT imaging

BACKGROUND

Laparoscopic liver surgery is particularly challenging owing to restricted access, risk of bleeding, and lack of haptic feedback. Navigation systems have the potential to improve information on the exact position of intrahepatic tumors, and thus facilitate oncological resection. This study aims to evaluate the feasibility of a commercially available augmented reality (AR) guidance system employing intraoperative robotic C-arm cone-beam computed tomography (CBCT) for laparoscopic liver surgery.

METHODS

A human liver-like phantom with 16 target fiducials was used to evaluate the Syngo iPilot(®) AR system. Subsequently, the system was used for the laparoscopic resection of a hepatocellular carcinoma in segment 7 of a 50-year-old male patient.

RESULTS

In the phantom experiment, the AR system showed a mean target registration error of 0.96 ± 0.52 mm, with a maximum error of 2.49 mm. The patient successfully underwent the operation and showed no postoperative complications.

CONCLUSION

The use of intraoperative CBCT and AR for laparoscopic liver resection is feasible and could be considered an option for future liver surgery in complex cases.