Design and preliminary validation of a high-fidelity vascular simulator for robot-assisted manipulation.

The number of robot-assisted minimally invasive surgeries is increasing annually, together with the need for dedicated and effective training. Surgeons need to learn how to address the novel control modalities of surgical instruments and the loss of haptic feedback, which is a common feature of most surgical robots. High-fidelity physical simulation has proved to be a valid training tool, and it might help in fulfilling these learning needs. In this regard, a high-fidelity sensorized simulator of vascular structures was designed, fabricated and preliminarily validated. The main objective of the simulator is to train novices in robotic surgery to correctly perform vascular resection procedures without applying excessive strain to tissues. The vessel simulator was integrated with soft strain sensors to quantify and objectively assess manipulation skills and to provide real-time feedback to the trainee during a training session. Additionally, a portable and user-friendly training task board was produced to replicate anatomical constraints. The simulator was characterized in terms of its mechanical properties, demonstrating its realism with respect to human tissues. Its face, content and construct validity, together with its usability, were assessed by implementing a training scenario with 13 clinicians, and the results were generally positive.

Neonatal intubation: what are we doing?

How and when the forces are applied during neonatal intubation are currently unknown. This study investigated the pattern of the applied forces by using sensorized laryngoscopes during the intubation process in a neonatal manikin. Nine users of direct laryngoscope and nine users of straight-blade video laryngoscope were included in a neonatal manikin study. During each procedure, relevant forces were measured using a force epiglottis sensor that was placed on the distal surface of the blade. The pattern of the applied forces could be divided into three sections. With the direct laryngoscope, the first section showed either a quick rise of the force or a discontinuous rise with several peaks; after reaching the maximum force, there was a sort of plateau followed by a quick drop of the applied forces. With the video laryngoscope, the first section showed a quick rise of the force; after reaching the maximum force, there was an irregular and heterogeneous plateau, followed by heterogeneous decreases of the applied forces. Moreover, less forces were recorded when using the video laryngoscope.    Conclusions: This neonatal manikin study identified three sections in the diagram of the forces applied during intubation, which likely mirrored the three main phases of intubation. Overall, the pattern of each section showed some differences in relation to the laryngoscope (direct or video) that was used during the procedure. These findings may provide useful insights for improving the understanding of the procedure. What is Known: • Neonatal intubation is a life-saving procedure that requires a skilled operator and may cause direct trauma to the tissues and precipitate adverse reactions. • Intubation with a videolaryngoscope requires less force than with a direct laryngoscope, but how and when the forces are applied during the whole neonatal intubation procedure are currently unknown. What is New: • Forces applied to the epiglottis during intubation can be divided into three sections: (i) an initial increase, (ii) a sort of plateau, and (iii) a decrease. • The pattern of each section shows some differences in relation to the laryngoscope (direct or videolaryngoscope) that is used during the procedure.

A Framework for the Evaluation of Human Machine Interfaces of Robot-Assisted Colonoscopy.

The Human Machine Interface (HMI) of intraluminal robots has a crucial impact on the clinician's performance. It increases or decreases the difficulty of the tasks, and is connected to the users' physical and mental stress. OBJECTIVE: This article presents a framework to compare and evaluate different HMIs for robotic colonoscopy, with the objective of identifying the optimal HMI that minimises the clinician's effort and maximises the clinical outcomes. METHODS: The framework comprises a 1) a virtual simulator (clinically validated), 2) wearable sensors measuring the cognitive load, 3) a data collection unit of metrics correlated to the clinical performance, and 4) questionnaires exploring the users' impressions and perceived stress. The framework was tested with 42 clinicians investigating the optimal device for tele-operated control of robotic colonoscopes. Two control devices were selected and compared: a haptic serial-kinematic device and a standard videogame joypad. RESULTS: The haptic device was preferred by the endoscopists, but the joypad enabled better clinical performance and reduced cognitive and physical load. CONCLUSION: The framework can be used to evaluate different aspects of a HMI, both hardware and software, and determine the optimal HMI that can reduce the burden on clinicians while improving the clinical outcome. SIGNIFICANCE: The findings of this study, and of future studies performed with this framework, can inform the design and development of HMIs for intraluminal robots, leading to improved clinical performance, reduced physical and mental stress for clinicians, and ultimately better patient outcomes.

Artificial intelligence meets medical robotics.

Artificial intelligence (AI) applications in medical robots are bringing a new era to medicine. Advanced medical robots can perform diagnostic and surgical procedures, aid rehabilitation, and provide symbiotic prosthetics to replace limbs. The technology used in these devices, including computer vision, medical image analysis, haptics, navigation, precise manipulation, and machine learning (ML) , could allow autonomous robots to carry out diagnostic imaging, remote surgery, surgical subtasks, or even entire surgical procedures. Moreover, AI in rehabilitation devices and advanced prosthetics can provide individualized support, as well as improved functionality and mobility (see the figure). The combination of extraordinary advances in robotics, medicine, materials science, and computing could bring safer, more efficient, and more widely available patient care in the future. -Gemma K. Alderton.

A magnetic endourethral sphincter against stress urinary incontinence: preliminary pilot study in humans.

BACKGROUND: Urinary incontinence (UI) is a common and frustrating condition that affects patients' quality of life as well as the Healthcare systems. Currently, the most severe cases of UI are treated using implanted, invasive artificial sphincters. We propose an innovative, minimally invasive magnetic endourethral sphincter for the treatment of stress UI (SUI) in patients for whom previous medical and surgical treatments have failed. METHODS: Six patients with severe SUI were enrolled at a single center and underwent cystoscopic sphincter implantation. After 10 days, correct device position was confirmed by ultrasonography. The sphincter was explanted after 28 days. RESULTS: In all patients, the sphincter was successfully implanted using an endoscopic approach. One patient reached the end of the pilot test (28 days) with the sphincter correctly placed. Patients' responses on the International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form questionnaire improved from a score of 18 out of 21 at the screening visit (UI without reasons) to a score of 3 out of 21 (almost perfect continence). No major pain and discomfort were reported. CONCLUSIONS: This study showed the feasibility of sphincter implantation, explantation, and overall tolerability, although a redesign of the sphincter distal part is needed.

Applied forces with direct versus indirect laryngoscopy in neonatal intubation: a randomized crossover mannequin study.

PURPOSE: In adult mannequins, videolaryngoscopy improves glottic visualization with lower force applied to upper airway tissues and reduced task workload compared with direct laryngoscopy. This trial compared oropharyngeal applied forces and subjective workload during direct vs indirect (video) laryngoscopy in a neonatal mannequin. METHODS: We conducted a randomized crossover trial of intubation with direct laryngoscopy, straight blade videolaryngoscopy, and hyperangulated videolaryngoscopy in a neonatal mannequin. Thirty neonatal/pediatric/anesthesiology consultants and residents participated. The primary outcome measure was the maximum peak force applied during intubation. Secondary outcome measures included the average peak force applied during intubation, time needed to intubate, and subjective workload. RESULTS: Direct laryngoscopy median forces on the epiglottis were 8.2 N maximum peak and 6.8 N average peak. Straight blade videolaryngoscopy median forces were 4.7 N maximum peak and 3.6 N average peak. Hyperangulated videolaryngoscopy median forces were 2.8 N maximum peak and 2.1 N average peak. The differences were significant between direct laryngoscopy and straight blade videolaryngoscopy, and between direct laryngoscopy and hyperangulated videolaryngoscopy. Significant differences were also found in the top 10th percentile forces on the epiglottis and palate, but not in the median forces on the palate. Time to intubation and subjective workload were comparable with videolaryngoscopy vs direct laryngoscopy. CONCLUSIONS: The lower force applied during videolaryngoscopy in a neonatal mannequin model suggests a possible benefit in reducing potential patient harm during intubation, but the clinical implications require assessment in future studies. REGISTRATION: ClinicalTrials.gov (NCT05197868); registered 20 January 2022.

RéSUMé: OBJECTIF: Sur les mannequins adultes, la vidéolaryngoscopie améliore la visualisation glottique avec une force plus faible appliquée aux tissus des voies aériennes supérieures et une charge de travail réduite par rapport à la laryngoscopie directe. Cette étude a comparé les forces appliquées sur la zone oropharyngée et la charge de travail subjective au cours d'une laryngoscopie directe vs indirecte (vidéolaryngoscopie) sur un mannequin néonatal. MéTHODE: Nous avons réalisé une étude randomisée croisée d'intubation par laryngoscopie directe, vidéolaryngoscopie à lame droite et vidéolaryngoscopie avec lame hyperangulée sur un mannequin néonatal. Trente spécialistes diplômés et résidents en néonatologie, en pédiatrie et en anesthésiologie y ont participé. Le critère d'évaluation principal était le pic de force maximal obtenu pendant l'intubation. Les critères d'évaluation secondaires comprenaient la force maximale moyenne appliquée pendant l'intubation, le temps nécessaire pour intuber et la charge de travail subjective. RéSULTATS: Les forces médianes appliquées sur l'épiglotte lors de la laryngoscopie directe étaient de 8,2 N pour le pic maximum et de 6,8 N pour le pic moyen. Les forces médianes appliquées lors de la vidéolaryngoscopie à lame droite étaient de 4,7 N pour le pic maximum et de 3,6 N pour le pic moyen. Les forces médianes appliquées lors de la vidéolaryngoscopie avec lame hyperangulée étaient de 2,8 N pour le pic maximum et de 2,1 N pour le pic moyen. Les différences étaient significatives entre la laryngoscopie directe et la vidéolaryngoscopie à lame droite, et entre la laryngoscopie directe et la vidéolaryngoscopie avec lame hyperangulée. Des différences significatives ont également été observées dans le 10e percentile supérieur des forces sur l'épiglotte et le palais, mais pas dans les forces médianes sur le palais. Le délai d'intubation et la charge de travail subjective étaient comparables entre la vidéolaryngoscopie et la laryngoscopie directe. CONCLUSION: La force plus faible appliquée lors de la vidéolaryngoscopie dans un modèle de mannequin néonatal suggère un avantage possible de réduction des lésions potentielles pour le patient pendant l'intubation, mais les implications cliniques doivent être évaluées dans des études futures. ENREGISTREMENT DE L'éTUDE: ClinicalTrials.gov (NCT05197868); enregistré le 20 janvier 2022.

Hydraulic Detrusor for Artificial Bladder Active Voiding.

The gold standard treatment for bladder cancer is radical cystectomy that implies bladder removal coupled to urinary diversions. Despite the serious complications and the impossibility of controlled active voiding, bladder substitution with artificial systems is a challenge and cannot represent a real option, yet. In this article, we present hydraulic artificial detrusor prototypes to control and drive the voiding of an artificial bladder (AB). These prototypes rely on two actuator designs (origami and bellows) based either on negative or positive operating pressure, to be combined with an AB structure. Based on the bladder geometry and size, we optimized the actuators in terms of contraction/expansion performances, minimizing the liquid volume required for actuation and exploring different actuator arrangements to maximize the voiding efficiency. To operate the actuators, an ad hoc electrohydraulic circuit was developed for transferring liquid between the actuators and a reservoir, both of them intended to be implanted. The AB, actuators, and reservoir were fabricated with biocompatible flexible thermoplastic materials by a heat-sealing process. We assessed the voiding efficiency with benchtop experiments by varying the actuator type and arrangement at different simulated patient positions (horizontal, 45° tilted, and vertical) to identify the optimal configuration and actuation strategy. The most efficient solution relies on two bellows actuators anchored to the AB. This artificial detrusor design resulted in a voiding efficiency of about 99%, 99%, and 89%, in the vertical, 45° tilted, and horizontal positions, respectively. The relative voiding time was reduced by about 17, 24, and 55 s compared with the unactuated bladder.

Semiautonomous Robotic Manipulator for Minimally Invasive Aortic Valve Replacement.

Aortic valve surgery is the preferred procedure for replacing a damaged valve with an artificial one. The ValveTech robotic platform comprises a flexible articulated manipulator and surgical interface supporting the effective delivery of an artificial valve by teleoperation and endoscopic vision. This article presents our recent work on force-perceptive, safe, semiautonomous navigation of the ValveTech platform prior to valve implantation. First, we present a force observer that transfers forces from the manipulator body and tip to a haptic interface. Second, we demonstrate how hybrid forward/inverse mechanics, together with endoscopic visual servoing, lead to autonomous valve positioning. Benchtop experiments and an artificial phantom quantify the performance of the developed robot controller and navigator. Valves can be autonomously delivered with a 2.0±0.5 mm position error and a minimal misalignment of 3.4±0.9°. The hybrid force/shape observer (FSO) algorithm was able to predict distributed external forces on the articulated manipulator body with an average error of 0.09 N. FSO can also estimate loads on the tip with an average accuracy of 3.3%. The presented system can lead to better patient care, delivery outcome, and surgeon comfort during aortic valve surgery, without requiring sensorization of the robot tip, and therefore obviating miniaturization constraints.

A novel microwave tool for robotic liver resection in minimally invasive surgery.

INTRODUCTION: During the last two decades, many surgical procedures have evolved from open surgery to minimally invasive surgery (MIS). This limited invasiveness has motivated the development of robotic assistance platforms to obtain better surgical outcomes. Nowadays, the da Vinci robot is a commercial tele-robotic platform widely used for different surgical applications. MATERIAL AND METHODS: In this work, the da Vinci Research Kit (dVRK), namely the research version of the da Vinci, is used to manipulate a novel microwave device in a teleoperation scenario. The dVRK provides an open source platform, so that the novel microwave tool, dedicated to prevention bleeding during hepatic resection surgery, is mechanically integrated on the slave side, while the software interface is adapted in order to correctly control tool pose. Tool integration is validated through in-vitro and ex-vivo tests performed by expert surgeons, meanwhile the coagulative efficacy of the developed tool in a perfused liver model was proved in in-vivo tests. RESULTS AND CONCLUSIONS: An innovative microwave tool for liver robotic resection has been realized and integrated into a surgical robot. The tool can be easily operated through the dVRK without limiting the intuitive and friendly use, and thus easily reaching the hemostasis of vessels.

Shape Reconstruction Processes for Interventional Application Devices: State of the Art, Progress, and Future Directions.

Soft and continuum robots are transforming medical interventions thanks to their flexibility, miniaturization, and multidirectional movement abilities. Although flexibility enables reaching targets in unstructured and dynamic environments, it also creates challenges for control, especially due to interactions with the anatomy. Thus, in recent years lots of efforts have been devoted for the development of shape reconstruction methods, with the advancement of different kinematic models, sensors, and imaging techniques. These methods can increase the performance of the control action as well as provide the tip position of robotic manipulators relative to the anatomy. Each method, however, has its advantages and disadvantages and can be worthwhile in different situations. For example, electromagnetic (EM) and Fiber Bragg Grating (FBG) sensor-based shape reconstruction methods can be used in small-scale robots due to their advantages thanks to miniaturization, fast response, and high sensitivity. Yet, the problem of electromagnetic interference in the case of EM sensors, and poor response to high strains in the case of FBG sensors need to be considered. To help the reader make a suitable choice, this paper presents a review of recent progress on shape reconstruction methods, based on a systematic literature search, excluding pure kinematic models. Methods are classified into two categories. First, sensor-based techniques are presented that discuss the use of various sensors such as FBG, EM, and passive stretchable sensors for reconstructing the shape of the robots. Second, imaging-based methods are discussed that utilize images from different imaging systems such as fluoroscopy, endoscopy cameras, and ultrasound for the shape reconstruction process. The applicability, benefits, and limitations of each method are discussed. Finally, the paper draws some future promising directions for the enhancement of the shape reconstruction methods by discussing open questions and alternative methods.

A decade retrospective of medical robotics research from 2010 to 2020.

Robotics is a forward-looking discipline. Attention is focused on identifying the next grand challenges. In an applied field such as medical robotics, however, it is important to plan the future based on a clear understanding of what the research community has recently accomplished and where this work stands with respect to clinical needs and commercialization. This Review article identifies and analyzes the eight key research themes in medical robotics over the past decade. These thematic areas were identified using search criteria that identified the most highly cited papers of the decade. Our goal for this Review article is to provide an accessible way for readers to quickly appreciate some of the most exciting accomplishments in medical robotics over the past decade; for this reason, we have focused only on a small number of seminal papers in each thematic area. We hope that this article serves to foster an entrepreneurial spirit in researchers to reduce the widening gap between research and translation.

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.

Training Simulators for Gastrointestinal Endoscopy: Current and Future Perspectives.

Gastrointestinal (GI) endoscopy is the gold standard in the detection and treatment of early and advanced GI cancers. However, conventional endoscopic techniques are technically demanding and require visual-spatial skills and significant hands-on experience. GI endoscopy simulators represent a valid solution to allow doctors to practice in a pre-clinical scenario. From the first endoscopy mannequin, developed in 1969, several simulation platforms have been developed, ranging from purely mechanical systems to more complex mechatronic devices and animal-based models. Considering the recent advancement of technologies (e.g., artificial intelligence, augmented reality, robotics), simulation platforms can now reach high levels of realism, representing a valid and smart alternative to standard trainee/mentor learning programs. This is particularly true nowadays, when the current demographic trend and the most recent pandemic demand, more than ever, the ability to cope with many patients. This review offers a broad view of the technology available for GI endoscopy training, including platforms currently in the market and the relevant advancements in this research and application field. Additionally, new training needs and new emerging technologies are discussed to understand where medical education is heading.

Smart Implantable Artificial Bladder: An Integrated Design for Organ Replacement.

Substituting the natural bladder with an artificial solution, after cancer and other pathologies, is an ambitious challenge in biomedical engineering. In this work we propose a fully implantable smart artificial bladder system (ABS) that collects urinary fluids and provides the subject with real-time feedback on the implant status. To achieve long term duration, the ABS was designed to be unstretchable in order to be treated with urine resistant coatings and included built-in passive check valves preventing reflux to kidneys. To estimate the amount of fluid collected, the ABS was provided with four electromagnetic distance sensing units and a control unit. An algorithm implemented on an embedded controller enabled the reconstruction of the bladder volume through sensors readings. A wireless data transfer system allows for providing a real-time feedback to the subject. Bench tests validated volume reconstruction accuracy and ex-vivo experiments verified the implantability of the proposed device on a human cadaver, proving the reliability of a Bluetooth data transmission system and paving the way towards an in-body/out-body communication. The proposed solution has the potential to overcome the limitations of currently available replacement strategies towards a new generation of implantable devices for lost organ functions replacement.

ValveTech: A Novel Robotic Approach for Minimally Invasive Aortic Valve Replacement.

OBJECTIVE: Aortic valve disease is the most common heart disease in the elderly calling for replacement with an artificial valve. The presented surgical robot aims to provide a highly controllable instrument for efficient delivery of an artificial valve by the help of integrated endoscopic vision. METHODS: A robot (called ValveTech), intended for minimally invasive surgery (MIS) and consisting of a flexible cable driven manipulator, a passive arm, and a control unit has been designed and prototyped. The flexible manipulator has several features (e.g., stabilizing flaps, tiny cameras, dexterous introducer and custom cartridge) to help the proper valve placement. It provides 5 degrees of freedom for reaching the operative site via mini-thoracotomy; it adjusts the valve and expands it at the optimal position. The robot was evaluated by ten cardiac surgeons following a real surgical scenario in artificial chest simulator with an aortic mockup. Moreover, after each delivery, the expanded valve was evaluated objectively in comparison with the ideal position. RESULTS: The robot performances were evaluated positively by surgeons. The trials resulted in faster delivery and an average misalignment distance of 3.8 mm along the aorta axis; 16.3 degrees rotational angle around aorta axis and 8.8 degrees misalignment of the valve commissure plane to the ideal plane were measured. CONCLUSION: The trials successfully proved the proposed system for valve delivery under endoscopic vision. SIGNIFICANCE: The ValveTech robot can be an alternative solution for minimally invasive aortic valve surgery and improve the quality of the operation both for surgeons and patients.

Soft Graspers for Safe and Effective Tissue Clutching in Minimally Invasive Surgery.

OBJECTIVE: Surgical graspers must be safe, not to damage tissue, and effective, to establish a stable contact for operation. For conventional rigid graspers, these requirements are conflicting and tissue damage is often induced. We thus proposed novel soft graspers, based on morphing jaws that increase contact area with clutching force. METHODS: We introduced two soft jaw concepts: DJ and CJ. They were designed (using analytical and numerical models) and prototyped (10 mm diameter, 10 mm span). Corresponding graspers were obtained by integrating the jaws into a conventional tool used in the dVRK surgical robotics platform. Morphing performance was experimentally characterized. Jaw-tissue interaction was quantitatively assessed through damage indicators obtained from ex vivo tests and histological analysis, also comparing DJ, CJ and dVRK rigid jaws. Soft graspers were demonstrated through ex vivo tests on dVRK. Ex vivo tests and related analysis were devised/performed with medical doctors. RESULTS: Design goal was achieved for both soft jaws: by morphing, contact area exceeded by 20-30% the maximum area allowed by encumbrance specifications to rigid jaws. Experimental characterization was in good agreement with model predictions (error ≈ 4%). Damage indicators showed differences amongst DJ, CJ and dVRK jaws (ANOVA p-value  =  0.0005): damage was one order of magnitude lower for soft graspers (each pairwise comparison was statistically significant). CONCLUSION: We proposed and demonstrated soft graspers potentially less harmful to tissue than conventional graspers. SIGNIFICANCE: Beyond minimally invasive surgery, the proposed concepts and design methodology can foster the development of graspers for soft robotics.

Acoustic Coupling Quantification in Ultrasound-Guided Focused Ultrasound Surgery: Simulation-Based Evaluation and Experimental Feasibility Study.

Adequate acoustic coupling between the therapeutic transducer and the patient's body is essential for safe and efficient focused ultrasound surgery (FUS). There is currently no quantitative method for acoustic coupling verification in ultrasound-guided FUS. In this work, a quantitative method was developed and a related metric was introduced: the acoustic coupling coefficient. This metric associates the adequacy of the acoustic coupling with the reflected signals recorded through an imaging probe during a low-energy sonication. The acoustic coupling issue was simulated in silico and validated through in vitro tests. Our results indicated a sigmoidal behavior of the introduced metric as the contact surface between the coupling system and the patient's skin increases. The proposed method could be a safety-check criterion for verifying the adequacy of the acoustic coupling before starting the FUS treatment, thus ensuring efficient energy transmission to the target and preventing damage to both the patient and the instrumentation.

Robotic-Assisted Colonoscopy Platform with a Magnetically-Actuated Soft-Tethered Capsule.

Background and Aims: Colorectal cancer (CRC) is a major cause of morbidity and mortality worldwide. Despite offering a prime paradigm for screening, CRC screening is often hampered by invasiveness. Endoo is a potentially painless colonoscopy method with an active locomotion tethered capsule offering diagnostic and therapeutic capabilities. Materials and Methods: The Endoo system comprises a soft-tethered capsule, which embeds a permanent magnet controlled by an external robot equipped with a second permanent magnet. Capsule navigation is achieved via closed-loop interaction between the two magnets. Ex-vivo tests were conducted by endoscopy experts and trainees to evaluate the basic key features, usability, and compliance in comparison with conventional colonoscopy (CC) in feasibility and pilot studies. Results: Endoo showed a 100% success rate in operating channel and target approach tests. Progression of the capsule was feasible and repeatable. The magnetic link was lost an average of 1.28 times per complete procedure but was restored in 100% of cases. The peak value of interaction forces was higher in the CC group than the Endoo group (4.12N vs. 1.17N). The cumulative interaction forces over time were higher in the CC group than the Endoo group between the splenic flexure and mid-transverse colon (16.53Ns vs. 1.67Ns, p < 0.001), as well as between the hepatic flexure and cecum (28.77Ns vs. 2.47Ns, p = 0.005). The polyp detection rates were comparable between groups (9.1 ± 0.9% vs. 8.7 ± 0.9%, CC and Endoo respectively, per procedure). Robotic colonoscopies were completed in 67% of the procedures performed with Endoo (53% experts and 100% trainees). Conclusions: Endoo allows smoother navigation than CC and possesses comparable features. Although further research is needed, magnetic capsule colonoscopy demonstrated promising results compared to CC.

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.

Pulsatile Drug Delivery System Triggered by Acoustic Radiation Force.

Since biological systems exhibit a circadian rhythm (24-hour cycle), they are susceptible to the timing of drug administration. Indeed, several disorders require a therapy that synchronizes with the onset of symptoms. A targeted therapy with spatially and temporally precise controlled drug release can guarantee a considerable gain in terms of efficacy and safety of the treatment compared to traditional pharmacological methods, especially for chronotherapeutic disorders. This paper presents a proof of concept of an innovative pulsatile drug delivery system remotely triggered by the acoustic radiation force of ultrasound. The device consists of a case, in which a drug-loaded gel can be embedded, and a sliding top that can be moved on demand by the application of an acoustic stimulus, thus enabling drug release. Results demonstrate for the first time that ultrasound acoustic radiation force (up to 0.1 N) can be used for an efficient pulsatile drug delivery (up to 20 µg of drug released for each shot).