Evaluation of Haptic Feedback on Bimanually Teleoperated Laparoscopy for Endometriosis Surgery

Paranoid About Androids: A Review of Robotics in Radiology

In tandem with the ever-increasing global population, the demand for diagnostic radiology service provision is on the rise and at a disproportionate rate compared to the number of radiologists available to practice. The current "revolution in robotics" promises to alleviate personnel shortages in many sectors of industry, including medicine. Despite negative depictions of robots in popular culture, their multiple potential benefits cannot be overlooked, in particular when it comes to health service provision. The type of robots used for interventional procedures are largely robotic-assistance devices, such as the Da Vinci surgical robot. Advances have also been made with regards to robots for image-guided percutaneous needle placement, which have demonstrated superior accuracy compared to manual methods. It is likely that artificial intelligence will come to play a key role in the field of robotics and will result in an increase in the levels of robotic autonomy attainable. However, this concept is not without ethical and legal considerations, most notably who is responsible should an error occur; the physician, the robot manufacturer, software engineers, or the robot itself? Efforts have been made to legislate in order to protect against the potentially harmful effects of unexplainable "black-box" decision outputs of artificial intelligence systems. In order to be accepted by patients, studies have shown that the perceived level of trustworthiness and predictability of robots is crucial. Ultimately, effective, widespread implementation of medical robotic systems will be contingent on developers remaining cognizant of factors that increase human acceptance, as well as ensuring compliance with regulations.

Evaluation of forces applied to tissues during robotic-assisted surgical tasks using a novel force feedback technology

BACKGROUND

The absence of force feedback (FFB) is considered a technical limitation in robotic-assisted surgery (RAS). This pre-clinical study aims to evaluate the forces applied to tissues using a novel integrated FFB technology, which allows surgeons to sense forces exerted at the instrument tips.

METHODS

Twenty-eight surgeons with varying experience levels employed FFB instruments to perform three robotic-assisted surgical tasks, including retraction, dissection, and suturing, on inanimate or ex-vivo models, while the instrument sensors recorded and conveyed the applied forces to the surgeon hand controllers of the robotic system. Generalized Estimating Equations (GEE) models were used to analyze the mean and maximal forces applied during each task with the FFB sensor at the "Off" setting compared to the "High" sensitivity setting for retraction and to the "Low", "Medium", and "High" sensitivity settings for dissection and suturing. Sub-analysis was also performed on surgeon experience levels.

RESULTS

The use of FFB at any of the sensitivity settings resulted in a significant reduction in both the mean and maximal forces exerted on tissue during all three robotic-assisted surgical tasks (p < 0.0001). The maximal force exerted, potentially associated with tissue damage, was decreased by 36%, 41%, and 55% with the use of FFB at the "High" sensitivity setting while performing retraction, dissection, and interrupted suturing tasks, respectively. Further, the use of FFB resulted in substantial reductions in force variance during the performance of all three types of tasks. In general, reductions in mean and maximal forces were observed among surgeons at all experience levels. The degree of force reduction depends on the sensitivity setting selected and the types of surgical tasks evaluated.

CONCLUSIONS

Our findings demonstrate that the utilization of FFB technology integrated in the robotic surgical system significantly reduced the forces exerted on tissue during the performance of surgical tasks at all surgeon experience levels. The reduction in the force applied and a consistency of force application achieved with FFB use, could result in decreases in tissue trauma and blood loss, potentially leading to better clinical outcomes in patients undergoing RAS. Future studies will be important to determine the impact of FFB instruments in a live clinical environment.

The benefits of haptic feedback in robot assisted surgery and their moderators: a meta-analysis

Robot assisted surgery (RAS) provides medical practitioners with valuable tools, decreasing strain during surgery and leading to better patient outcomes. While the loss of haptic sensation is a commonly cited disadvantage of RAS, new systems aim to address this problem by providing artificial haptic feedback. N = 56 papers that compared robotic surgery systems with and without haptic feedback were analyzed to quantify the performance benefits of restoring the haptic modality. Additionally, this study identifies factors moderating the effect of restoring haptic sensation. Overall results showed haptic feedback was effective in reducing average forces (Hedges' g = 0.83) and peak forces (Hedges' g = 0.69) applied during surgery, as well as reducing the completion time (Hedges' g = 0.83). Haptic feedback has also been found to lead to higher accuracy (Hedges' g = 1.50) and success rates (Hedges' g = 0.80) during surgical tasks. Effect sizes on several measures varied between tasks, the type of provided feedback, and the subjects' levels of surgical expertise, with higher levels of expertise generally associated with smaller effect sizes. No significant differences were found between virtual fixtures and rendering contact forces. Implications for future research are discussed.

A Sensorised Surgical Glove to Analyze Forces During Neurosurgery

BACKGROUND

Measuring intraoperative forces in real time can provide feedback mechanisms to improve patient safety and surgical training. Previous force monitoring has been achieved through the development of specialized and adapted instruments or use designs that are incompatible with neurosurgical workflow.

OBJECTIVE

To design a universal sensorised surgical glove to detect intraoperative forces, applicable to any surgical procedure, and any surgical instrument in either hand.

METHODS

We created a sensorised surgical glove that was calibrated across 0 to 10 N. A laboratory experiment demonstrated that the sensorised glove was able to determine instrument-tissue forces. Six expert and 6 novice neurosurgeons completed a validated grape dissection task 20 times consecutively wearing the sensorised glove. The primary outcome was median and maximum force (N).

RESULTS

The sensorised glove was able to determine instrument-tissue forces reliably. The average force applied by experts (2.14 N) was significantly lower than the average force exerted by novices (7.15 N) ( P = .002). The maximum force applied by experts (6.32 N) was also significantly lower than the maximum force exerted by novices (9.80 N) ( P = .004). The sensorised surgical glove's introduction to operative workflow was feasible and did not impede on task performance.

CONCLUSION

We demonstrate a novel and scalable technique to detect forces during neurosurgery. Force analysis can provide real-time data to optimize intraoperative tissue forces, reduce the risk of tissue injury, and provide objective metrics for training and assessment.

Force-based assessment of tissue handling skills in simulation training for robot-assisted surgery

INTRODUCTION

Although robotic-assisted surgery is increasingly performed, objective assessment of technical skills is lacking. The aim of this study is to provide validity evidence for objective assessment of technical skills for robotic-assisted surgery.

METHODS

An international multicenter study was conducted with participants from the academic hospitals Heidelberg University Hospital (Germany, Heidelberg) and the Amsterdam University Medical Centers (The Netherlands, Amsterdam). Trainees with distinctly different levels of robotic surgery experience were divided into three groups (novice, intermediate, expert) and enrolled in a training curriculum. Each trainee performed six trials of a standardized suturing task using the da Vinci Surgical System. Using the ForceSense system, five force-based parameters were analyzed, for objective assessment of tissue handling skills. Mann-Whitney U test and linear regression were used to analyze performance differences and the Wilcoxon signed-rank test to analyze skills progression.

RESULTS

A total of 360 trials, performed by 60 participants, were analyzed. Significant differences between the novices, intermediates and experts were observed regarding the total completion time (41 s vs 29 s vs 22 s p = 0.003), mean non zero force (29 N vs 33 N vs 19 N p = 0.032), maximum impulse (40 Ns vs 31 Ns vs 20 Ns p = 0.001) and force volume (38 N³ vs 32 N³ vs 22 N³ p = 0.018). Furthermore, the experts showed better results in mean non-zero force (22 N vs 13 N p = 0.015), maximum impulse (24 Ns vs 17 Ns p = 0.043) and force volume (25 N³ vs 16 N³ p = 0.025) compared to the intermediates (p ≤ 0.05). Lastly, learning curve improvement was observed for the total task completion time, mean non-zero force, maximum impulse and force volume (p ≤ 0.05).

CONCLUSION

Construct validity for force-based assessment of tissue handling skills in robot-assisted surgery is established. It is advised to incorporate objective assessment and feedback in robot-assisted surgery training programs to determine technical proficiency and, potentially, to prevent tissue trauma.

The current role of robotic surgery in endometriosis management

INTRODUCTION

Endometriosis is a chronic inflammatory disease that affects approximately 10%-15% of women of childbearing age. Laparoscopic surgery is the preferred surgical approach. Recently, robotic surgery has been used for benign gynecologic surgery, but its role in the treatment of endometriosis is still unknown.

AREAS COVERED

We included studies that evaluated the outcomes of robotic surgery for endometriosis. Using the keywords 'endometriosis' and 'robotics', a comprehensive literature search on PubMed, Embase, and the Cochrane Library was performed in July 2021.

EXPERT OPINION

Robotic surgery for endometriosis has similar outcomes as conventional laparoscopy, with no evidence of increased complication rates. Despite the non-inferiority of the surgical route, the associated costs of robotic surgery limit its availability. Rapid development of robot-assisted surgery necessitates long-term prospective randomized controlled trials. However, the limitations of robotic surgery should not be overlooked. If robotic surgery can facilitate the spread of minimally invasive surgery, it will be necessary to evaluate the cost, availability, complexity of the lesions, and most importantly, the results of patient satisfaction and values of value-based medicine.

Toward Mechanochromic Soft Material-Based Visual Feedback for Electronics-Free Surgical Effectors

A chromogenically reversible, mechanochromic pressure sensor is integrated into a mininvasive surgical grasper compatible with the da Vinci robotic surgical system. The sensorized effector, also featuring two soft-material jaws, encompasses a mechanochromic polymeric inset doped with functionalized spiropyran (SP) molecule, designed to activate mechanochromism at a chosen pressure and providing a reversible color change. Considering such tools are systematically in the visual field of the operator during surgery, color change of the mechanochromic effector can help avoid tissue damage. No electronics is required to control the devised visual feedback. SP-doping of polydimethylsiloxane (2.5:1 prepolymer/curing agent weight ratio) permits to modulate the mechanochromic activation pressure, with lower values around 1.17 MPa for a 2% wt. SP concentration, leading to a shorter chromogenic recovery time of 150 s at room temperature (25 °C) under green light illumination. Nearly three-times shorter recovery time is observed at body temperature (37 °C). To the best of knowledge, this study provides the first demonstration of mechanochromic materials in surgery, in particular to sensorize unpowered surgical effectors, by avoiding dramatic increases in tool complexity due to additional electronics, thus fostering their application. The proposed sensing strategy can be extended to further tools and scopes.

A novel master-slave intraocular surgical robot with force feedback

BACKGROUND

Intraocular surgery is one of the most challenging microsurgeries. Unintended movements of human hand and lack of force feedback can seriously affect surgical safety.

METHODS

We developed a novel master-slave robotic system with force feedback to assist intraocular surgeries. Isomorphism design was adopted to achieve intuitive control of the system. Contact force between instrument tip and tissues was measured with a force sensor developed by our group. Real-time force feedback was provided with one linear voice coil motor and two magnetic particle brakes in the master manipulator.

RESULTS

Experiments were carried out to verify the proposed system. In the phantom experiment mimicking realistic surgical operations, the contact force significantly reduced by more than 30% with the force feedback when peeling the egg inner shell membranes.

CONCLUSIONS

Experimental results demonstrate the effectiveness of force feedback and indicate the promise of the presented master-slave robotic system for intraocular surgery assistance.

Tool-tissue forces in surgery: A systematic review

Background

Excessive tool-tissue interaction forces often result in tissue damage and intraoperative complications, while insufficient forces prevent the completion of the task. This review sought to explore the tool-tissue interaction forces exerted by instruments during surgery across different specialities, tissues, manoeuvres and experience levels.

Materials & methods

A PRISMA-guided systematic review was carried out using Embase, Medline and Web of Science databases.

Results

Of 462 articles screened, 45 studies discussing surgical tool-tissue forces were included. The studies were categorized into 9 different specialities with the mean of average forces lowest for ophthalmology (0.04N) and highest for orthopaedic surgery (210N). Nervous tissue required the least amount of force to manipulate (mean of average: 0.4N), whilst connective tissue (including bone) required the most (mean of average: 45.8). For manoeuvres, drilling recorded the highest forces (mean of average: 14N), whilst sharp dissection recorded the lowest (mean of average: 0.03N). When comparing differences in the mean of average forces between groups, novices exerted 22.7% more force than experts, and presence of a feedback mechanism (e.g. audio) reduced exerted forces by 47.9%.

Conclusions

The measurement of tool-tissue forces is a novel but rapidly expanding field. The range of forces applied varies according to surgical speciality, tissue, manoeuvre, operator experience and feedback provided. Knowledge of the safe range of surgical forces will improve surgical safety whilst maintaining effectiveness. Measuring forces during surgery may provide an objective metric for training and assessment. Development of smart instruments, robotics and integrated feedback systems will facilitate this.

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This review explores tool-tissue forces during surgery, a new and expanding field.

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Forces were lowest in ophthalmology (0.04N) and highest in orthopaedics (210N).

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Forces were lowest during sharp dissection (0.03N) and highest when drilling (14N).

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Being an expert (vs. novice) and having feedback mechanisms (e.g. haptic) reduced exerted forces.

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Development of force metrics will facilitate training, assessment & novel technology.

Discrete Sliding Mode Control Design for Bilateral Teleoperation System via Adaptive Extended State Observer

The goal of this paper is to improve the synchronization control performance of nonlinear teleoperation systems with system uncertainties in the presence of time delays. In view of the nonlinear discrete states of the teleoperation system in packet-switched communication networks, a new discrete sliding mode control (DSMC) strategy is performed via a new reaching law in task space. The new reaching law is designed to reduce the chattering and improve control performance. Moreover, an adaptive extended state observer (AESO) is used to estimate the total system disturbances. The additional gain of AESO is adjusted in time to decrease the estimation errors of both system states and disturbances automatically and improve the estimation performances of the AESO. Finally, the validity of the designed control strategy is demonstrated by both simulation and experiments. Furthermore, the experimental comparison results indicate that the improvement is achievable with the proposed AESO and DSMC.

Haptic Intracorporeal Palpation Using a Cable-Driven Parallel Robot: A User Study

OBJECTIVE

Intraoperative palpation is a surgical gesture jeopardized by the lack of haptic feedback which affects robotic minimally invasive surgery. Restoring the force reflection in teleoperated systems may improve both surgeons' performance and procedures' outcome.

METHODS

A force-based sensing approach was developed, based on a cable-driven parallel manipulator with anticipated seamless and low-cost integration capabilities in teleoperated robotic surgery. No force sensor on the end-effector is used, but tissue probing forces are estimated from measured cable tensions. A user study involving surgical trainees (n = 22) was conducted to experimentally evaluate the platform in two palpation-based test-cases on silicone phantoms. Two modalities were compared: visual feedback alone and both visual + haptic feedbacks available at the master site.

RESULTS

Surgical trainees' preference for the modality providing both visual and haptic feedback is corroborated by both quantitative and qualitative metrics. Hard nodules detection sensitivity improves (94.35 ± 9.1% vs 76.09 ± 19.15% for visual feedback alone), while also exerting smaller forces (4.13 ± 1.02 N vs 4.82 ± 0.81 N for visual feedback alone) on the phantom tissues. At the same time, the subjective perceived workload decreases.

CONCLUSION

Tissue-probe contact forces are estimated in a low cost and unique way, without the need of force sensors on the end-effector. Haptics demonstrated an improvement in the tumor detection rate, a reduction of the probing forces, and a decrease in the perceived workload for the trainees.

SIGNIFICANCE

Relevant benefits are demonstrated from the usage of combined cable-driven parallel manipulators and haptics during robotic minimally invasive procedures. The translation of robotic intraoperative palpation to clinical practice could improve the detection and dissection of cancer nodules.

Using Brain Activation to Evaluate Arrangements Aiding Hand-Eye Coordination in Surgical Robot Systems

GOAL

To realize intuitive, minimally invasive surgery, surgical robots are often controlled using master-slave systems. However, the surgical robot's structure often differs from that of the human body, so the arrangement between the monitor and master must reflect this physical difference. In this study, we validate the feasibility of an embodiment evaluation method that determines the arrangement between the monitor and master. In our constructed cognitive model, the brain's intraparietal sulcus activates significantly when somatic and visual feedback match. Using this model, we validate a cognitively appropriate arrangement between the monitor and master.

METHODS

In experiments, we measure participants' brain activation using an imaging device as they control the virtual surgical simulator. Two experiments are carried out that vary the monitor and hand positions.

CONCLUSION

There are two common arrangements of the monitor and master at the brain activation's peak: One is placing the monitor behind the master, so the user feels that the system is an extension of his arms into the monitor; the other arranges the monitor in front of the master, so the user feels the correspondence between his own arm and the virtual arm in the monitor.

SIGNIFICANCE

From these results, we conclude that the arrangement between the monitor and master impacts embodiment, enabling the participant to feel apparent posture matches in master-slave surgical robot systems.