Imperial College London

Dr George Mylonas

Faculty of MedicineDepartment of Surgery & Cancer

Lecturer in Robotics and Technology in Cancer
 
 
 
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Contact

 

+44 (0)20 3312 5145george.mylonas Website

 
 
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Location

 

Room 5Paterson WingSt Mary's Campus

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Summary

 

Publications

Publication Type
Year
to

102 results found

Robertson D, Sterke F, van Weteringen W, Arezzo A, Mintz Y, Nickel F, Technology committee of the European Association for Endoscopic Surgery EAES, Horeman Tet al., 2022, Characterisation of trocar associated gas leaks during laparoscopic surgery., Surg Endosc, Vol: 36, Pages: 4542-4551

BACKGROUND: During laparoscopy, the abdominal cavity is insufflated with carbon dioxide (CO2) that could become contaminated with viruses and surgical smoke. Medical staff is potentially exposed when this gas leaks into the operating room through the instruments and past trocar valves. No detailed studies currently exist that have quantified these leakage pathways. Therefore, the goal of this study was to quantify the gas leakages through trocars and instruments, during minimally invasive procedures. METHODS: A model of the surgical environment was created, consisting of a rigid container with an interface for airtight clamping of laparoscopic equipment such as trocars and surgical instruments. The model was insufflated to 15 mm Hg using a pressure generator and a pneumotachograph measured the equipment gas leak. A protocol of several use cases was designed to simulate the motions and forces the surgeon exerts on the trocar during surgery. RESULTS: Twenty-three individual trocars and twenty-six laparoscopic instruments were measured for leakage under the different conditions of the protocol. Trocar leakages varied between 0 L/min and more than 30 L/min, the instruments revealed a range of leakages between 0 L/min and 5.5 L/min. The results showed that leakage performance varied widely between trocars and instruments and that the performance and location of the valves influenced trocar leakage. CONCLUSIONS: We propose trocar redesigns to overcome specific causes of gas leaks. Moreover, an international testing standard for CO2 leakage for all new trocars and instruments is needed so surgical teams can avoid this potential health hazard when selecting new equipment.

Journal article

Arezzo A, Kruusmaa M, Mylonas G, 2022, From Bench to Bedside, IEEE Transactions on Medical Robotics and Bionics, Vol: 4, Pages: 297-299

Journal article

Nakajima K, Mintz Y, Nickel F, Arezzo A, EAES Technology Committeeet al., 2022, The EAES intellectual property awareness survey., Surg Endosc, Vol: 36, Pages: 3340-3346

INTRODUCTION: The protection of intellectual property (IP) is one of the fundamental elements in the process of medical device development. The significance of IP, however, is not well understood among clinicians and researchers. The purpose of this study was to evaluate the current status of IP awareness and IP-related behaviors among EAES members. METHODS: A web-based survey was conducted via questionnaires sent to EAES members. Data collected included participant demographics, level of understanding the need, new ideas and solutions, basic IP knowledge, e.g., employees' inventions and public disclosure, behaviors before and after idea disclosures. RESULTS: One hundred and seventy-nine completed forms were obtained through an email campaign conducted twice in 2019 (response rate = 4.8%). There was a dominancy in male, formally-trained gastrointestinal surgeons, working at teaching hospitals in European countries. Of the respondents, 71% demonstrated a high level of understanding the needs (frustration with current medical devices), with 66% developing specific solutions by themselves. Active discussion with others was done by 53%. Twenty-one percent of respondents presented their ideas at medical congresses, and 12% published in scientific journals. Only 20% took specific precautions or appropriate actions to protect their IPs before these disclosures. CONCLUSIONS: The current level of awareness of IP and IP-related issues is relatively low among EAES members. A structured IP training program to gain basic IP knowledge and skill should be considered a necessity for clinicians. These skills would serve to prevent the loss of legitimate IP rights and avoid failure in the clinical implementation of innovative devices for the benefit of patients.

Journal article

Hardon SF, Rahimi AM, Postema RR, Willuth E, Mintz Y, Arezzo A, Dankelman J, Nickel F, Horeman T, Baldari L, Boni L, Chand M, Ficuciello F, Fuchs H, Inaki N, Jimenez-Rodrigues R, Kim YW, Manfredi L, Marconi S, Mascagni P, Perretta S, Schijven M, Mylonas G, Myśliwiec P, Petz W, Sagiv C, Sánchez-Margallo JA, Sánchez-Margallo Fet al., 2022, Safe implementation of hand held steerable laparoscopic instruments: a survey among EAES surgeons, Updates in Surgery, ISSN: 2038-131X

The complexity of handheld steerable laparoscopic instruments (SLI) may impair the learning curve compared to conventional instruments when first utilized. This study aimed to provide the current state of interest in the use of SLI, the current use of these in daily practice and the type of training which is conducted before using SLI in the operating room (OR) on real patients. An online survey was distributed by European Association of Endoscopic Surgery (EAES) Executive Office to all active members, between January 4th and February 3rd, 2020. The survey consisted of 14 questions regarding the usage and training of steerable laparoscopic instruments. A total of 83 members responded, coming from 33 different countries. Twenty three percent of the respondents using SLI, were using the instruments routinely and of these 21% had not received any formal training in advance of using the instruments in real patients. Of all responding EAES members, 41% considered the instruments to potentially compromise patient safety due to their complexity, learning curve and the inexperience of the surgeons. The respondents reported the three most important aspects of a possible steerable laparoscopic instruments training curriculum to be: hands-on training, safe tissue handling and suturing practice. Finally, a major part of the respondents consider force/pressure feedback data to be of significant importance for implementation of training and assessment of safe laparoscopic and robotic surgery. Training and assessment of skills regarding safe implementation of steerable laparoscopic instruments is lacking. The respondents stressed the need for specific hands-on training during which feedback and assessment of skills should be guaranteed before operating on real patients.

Journal article

Golahmadi AK, Khan DZ, Mylonas G, Marcus Het al., 2021, Tool-tissue Forces in Surgery: A Systematic Review, Publisher: ELSEVIER SCIENCE INC, Pages: E70-E70, ISSN: 1072-7515

Conference paper

Runciman M, Avery J, Darzi A, Mylonas Get al., 2021, Open loop position control of soft hydraulic actuators for minimally invasive surgery, Applied Sciences-Basel, Vol: 11, Pages: 1-16, ISSN: 2076-3417

Minimally invasive surgery (MIS) presents many constraints on the design of robotic devices that can assist medical staff with a procedure. The limitations of conventional, rigid robotic devices have sparked interest in soft robotic devices for medical applications. However, problems still remain with the force exertion and positioning capabilities of soft robotic actuators, in conjunction with size restrictions necessary for MIS. In this article we present hydraulically actuated soft actuators that demonstrate highly repeatable open loop positioning and the ability to exert significant forces in the context of MIS. Open loop position control is achieved by changing the actuator volume, which causes contraction. In one degree of freedom (DOF) configurations, root mean square error (RMSE) values of 0.471 mm, 1.506 mm, and 0.350 mm were recorded for a single actuator against gravity, a single actuator with a pulley, and a horizontal antagonistic configuration, respectively. Hysteresis values of 0.711 mm, 0.958 mm, and 0.515 mm were reported in these experiments. In addition, different numbers of soft actuators were used in configurations two and three DOFs to demonstrate position control. When deactivated, the soft actuators are low-profile and flexible as they are constructed from thin films. As such, a robot with a deployable structure and three soft actuators was constructed. The robot is therefore able to reversibly transition from low to high volume and stiffness, which has potential applications in MIS. A user successfully controlled the deployable robot in a circle tracing task.

Journal article

Liu T, Yang T, Xu W, Mylonas G, Liang Bet al., 2021, Efficient Inverse Kinematics and Planning of a Hybrid Active and Passive Cable-Driven Segmented Manipulator, IEEE TRANSACTIONS ON SYSTEMS MAN CYBERNETICS-SYSTEMS, Vol: 52, Pages: 4233-4246, ISSN: 2168-2216

Journal article

Ezzat A, Kogkas A, Holt J, Thakkar R, Darzi A, Mylonas Get al., 2021, An eye-tracking based robotic scrub nurse: proof of concept, SURGICAL ENDOSCOPY AND OTHER INTERVENTIONAL TECHNIQUES, Vol: 35, Pages: 5381-5391, ISSN: 0930-2794

BackgroundWithin surgery, assistive robotic devices (ARD) have reported improved patient outcomes. ARD can offer the surgical team a “third hand” to perform wider tasks and more degrees of motion in comparison with conventional laparoscopy. We test an eye-tracking based robotic scrub nurse (RSN) in a simulated operating room based on a novel real-time framework for theatre-wide 3D gaze localization in a mobile fashion.MethodsSurgeons performed segmental resection of pig colon and handsewn end-to-end anastomosis while wearing eye-tracking glasses (ETG) assisted by distributed RGB-D motion sensors. To select instruments, surgeons (ST) fixed their gaze on a screen, initiating the RSN to pick up and transfer the item. Comparison was made between the task with the assistance of a human scrub nurse (HSNt) versus the task with the assistance of robotic and human scrub nurse (R&HSNt). Task load (NASA-TLX), technology acceptance (Van der Laan’s), metric data on performance and team communication were measured.ResultsOverall, 10 ST participated. NASA-TLX feedback for ST on HSNt vs R&HSNt usage revealed no significant difference in mental, physical or temporal demands and no change in task performance. ST reported significantly higher frustration score with R&HSNt. Van der Laan’s scores showed positive usefulness and satisfaction scores in using the RSN. No significant difference in operating time was observed.ConclusionsWe report initial findings of our eye-tracking based RSN. This enables mobile, unrestricted hands-free human–robot interaction intra-operatively. Importantly, this platform is deemed non-inferior to HSNt and accepted by ST and HSN test users.

Journal article

Kinross JM, Mason SE, Mylonas G, Darzi Aet al., 2021, Next-generation robotics in gastrointestinal surgery (vol 17, pg 430, 2020), NATURE REVIEWS GASTROENTEROLOGY & HEPATOLOGY, Vol: 18, Pages: 589-589, ISSN: 1759-5045

Journal article

Sivananthan A, Kogkas A, Glover B, Darzi A, Mylonas G, Patel Net al., 2021, A novel gaze-controlled flexible robotized endoscope; preliminary trial and report, SURGICAL ENDOSCOPY AND OTHER INTERVENTIONAL TECHNIQUES, Vol: 35, Pages: 4890-4899, ISSN: 0930-2794

BackgroundInterventional endoluminal therapy is rapidly advancing as a minimally invasive surgical technique. The expanding remit of endoscopic therapy necessitates precision control. Eye tracking is an emerging technology which allows intuitive control of devices. This was a feasibility study to establish if a novel eye gaze-controlled endoscopic system could be used to intuitively control an endoscope.MethodsAn eye gaze-control system consisting of eye tracking glasses, specialist cameras and a joystick was used to control a robotically driven endoscope allowing steering, advancement, withdrawal and retroflexion. Eight experienced and eight non-endoscopists used both the eye gaze system and a conventional endoscope to identify ten targets in two simulated environments: a sphere and an upper gastrointestinal (UGI) model.Completion of tasks was timed. Subjective feedback was collected from each participant on task load (NASA Task Load Index) and acceptance of technology (Van der Laan scale).ResultsWhen using gaze-control endoscopy, non-endoscopists were significantly quicker when using gaze-control rather than conventional endoscopy (sphere task 3:54 ± 1:17 vs. 9:05 ± 5:40 min, p = 0.012, and UGI model task 1:59 ± 0:24 vs 3:45 ± 0:53 min, p < .001).Non-endoscopists reported significantly higher NASA-TLX workload total scores using conventional endoscopy versus gaze-control (80.6 ± 11.3 vs 22.5 ± 13.8, p < .001). Endoscopists reported significantly higher total NASA-TLX workload scores using gaze control versus conventional endoscopy (54.2 ± 16 vs 26.9 ± 15.3, p = 0.012). All subjects reported that the gaze-control had positive ‘usefulness’ and ‘satisfaction’ score of 0.56 ± 0.83 and 1.43 &

Journal article

Ashraf H, Sodergren M, Mylonas G, Darzi A, Ashraf H, Sodergren M, Mylonas G, Darzi Aet al., 2021, 837 The Identification of Gaze Behaviour and Physiological Markers Associated With Making An Error During Laparoscopic Cholecystectomy, ASiT/MedAll Virtual Surgical Summit, Publisher: OXFORD UNIV PRESS, ISSN: 0007-1323

Conference paper

Khan DZ, Kafai Golahmadi A, Mylonas G, Marcus H, Khan DZ, Golahmadi AK, Mylonas G, Marcus Het al., 2021, 662 Tool-tissue Forces in Surgery: A Systematic Review, ASiT/MedAll Virtual Surgical Summit, Publisher: OXFORD UNIV PRESS, ISSN: 0007-1323

Conference paper

Golahmadi AK, Khan DZ, Mylonas GP, Marcus HJet al., 2021, Tool-tissue forces in surgery: A systematic review, Annals of Medicine and Surgery, Vol: 65, Pages: 1-7, ISSN: 2049-0801

BackgroundExcessive 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 & methodsA PRISMA-guided systematic review was carried out using Embase, Medline and Web of Science databases.ResultsOf 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%.ConclusionsThe 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.

Journal article

Saracino A, Oude-Vrielink TJC, Menciassi A, Sinibaldi E, Mylonas GPet al., 2020, Haptic Intracorporeal Palpation Using a Cable-Driven Parallel Robot: A User Study, IEEE TRANSACTIONS ON BIOMEDICAL ENGINEERING, Vol: 67, Pages: 3452-3463, ISSN: 0018-9294

Journal article

Arezzo A, Francis N, Mintz Y, Adamina M, Antoniou SA, Bouvy N, Copaescu C, de Manzini N, Di Lorenzo N, Morales-Conde S, Mueller-Stich BP, Nickel F, Popa D, Tait D, Thomas C, Nimmo S, Paraskevis D, Pietrabissa Aet al., 2020, EAES recommendations for recovery plan in minimally invasive surgery amid COVID-19 pandemic, SURGICAL ENDOSCOPY AND OTHER INTERVENTIONAL TECHNIQUES, Vol: 35, Pages: 1-17, ISSN: 0930-2794

BackgroundCOVID-19 pandemic presented an unexpected challenge for the surgical community in general and Minimally Invasive Surgery (MIS) specialists in particular. This document aims to summarize recent evidence and experts’ opinion and formulate recommendations to guide the surgical community on how to best organize the recovery plan for surgical activity across different sub-specialities after the COVID-19 pandemic.MethodsRecommendations were developed through a Delphi process for establishment of expert consensus. Domain topics were formulated and subsequently subdivided into questions pertinent to different surgical specialities following the COVID-19 crisis. Sixty-five experts from 24 countries, representing the entire EAES board, were invited. Fifty clinicians and six engineers accepted the invitation and drafted statements based on specific key questions. Anonymous voting on the statements was performed until consensus was achieved, defined by at least 70% agreement.ResultsA total of 92 consensus statements were formulated with regard to safe resumption of surgery across eight domains, addressing general surgery, upper GI, lower GI, bariatrics, endocrine, HPB, abdominal wall and technology/research. The statements addressed elective and emergency services across all subspecialties with specific attention to the role of MIS during the recovery plan. Eighty-four of the statements were approved during the first round of Delphi voting (91.3%) and another 8 during the following round after substantial modification, resulting in a 100% consensus.ConclusionThe recommendations formulated by the EAES board establish a framework for resumption of surgery following COVID-19 pandemic with particular focus on the role of MIS across surgical specialities. The statements have the potential for wide application in the clinical setting, education activities and research work across different healthcare systems.

Journal article

Avery J, Shulakova D, Runciman M, Mylonas GP, Darzi Aet al., 2020, Tactile sensor for minimally invasive surgery using Electrical Impedance Tomography, IEEE Transactions on Medical Robotics and Bionics, Vol: 2, Pages: 561-564, ISSN: 2576-3202

Whilst offering numerous benefits to patients, minimally invasive surgery (MIS) has a disadvantage in the loss of tactile feedback to the surgeon, traditionally offering valuable qualitative tissue assessment, such as tumour identification and localisation. Tactile sensors aim to overcome this loss of sensation by detecting tissue characteristics such as stiffness, composition and temperature. Tactile sensors have previously been incorporated into MIS robotic end effectors, which require lengthy scanning procedures due to localised sensitivity. Distributed tactile sensors, or “artificial skin” offer a map of tissue properties in a single instance but are often not suitable for MIS applications due to limited biocompatibility or large collapsed volumes. We propose a deployable, soft, tactile sensor with a deformable saline chamber and integrated Electrical Impedance Tomography (EIT) electrodes. During contact with tissue, the saline is displaced from the chamber and the lesion size and stiffness can be inferred from the resultant impedance changes. Through optimisation of the EIT measurement protocol and hardware the sensor was capable of localising the centre of mass of palpation targets within 1.5 mm in simulation and 2.3–4.6mm in phantom experiments. Reconstructed image metrics differentiated target objects from 8–30 mm.

Journal article

Cursi F, Mylonas GP, Kormushev P, 2020, Adaptive kinematic modelling for multiobjective control of a redundant surgical robotic tool, Robotics, Vol: 9, Pages: 68-68, ISSN: 2218-6581

Accurate kinematic models are essential for effective control of surgical robots. For tendon driven robots, which are common for minimally invasive surgery, the high nonlinearities in the transmission make modelling complex. Machine learning techniques are a preferred approach to tackle this problem. However, surgical environments are rarely structured, due to organs being very soft and deformable, and unpredictable, for instance, because of fluids in the system, wear and break of the tendons that lead to changes of the system’s behaviour. Therefore, the model needs to quickly adapt. In this work, we propose a method to learn the kinematic model of a redundant surgical robot and control it to perform surgical tasks both autonomously and in teleoperation. The approach employs Feedforward Artificial Neural Networks (ANN) for building the kinematic model of the robot offline, and an online adaptive strategy in order to allow the system to conform to the changing environment. To prove the capabilities of the method, a comparison with a simple feedback controller for autonomous tracking is carried out. Simulation results show that the proposed method is capable of achieving very small tracking errors, even when unpredicted changes in the system occur, such as broken joints. The method proved effective also in guaranteeing accurate tracking in teleoperation.

Journal article

Runciman M, Darzi A, Mylonas GP, 2020, Soft robotics in minimally invasive surgery (Part 2), Galvanotechnik, Vol: 111, Pages: 1236-1237, ISSN: 0016-4232

Journal article

Kinross JM, Mason SE, Mylonas G, Darzi Aet al., 2020, Next-generation robotics in gastrointestinal surgery, Nature Reviews Gastroenterology and Hepatology, Vol: 17, Pages: 430-440, ISSN: 1759-5045

The global numbers of robotic gastrointestinal surgeries are increasing. However, the evidence base for robotic gastrointestinal surgery does not yet support its widespread adoption or justify its cost. The reasons for its continued popularity are complex, but a notable driver is the push for innovation — robotic surgery is seen as a compelling solution for delivering on the promise of minimally invasive precision surgery — and a changing commercial landscape delivers the promise of increased affordability. Novel systems will leverage the robot as a data-driven platform, integrating advances in imaging, artificial intelligence and machine learning for decision support. However, if this vision is to be realized, lessons must be heeded from current clinical trials and translational strategies, which have failed to demonstrate patient benefit. In this Perspective, we critically appraise current research to define the principles on which the next generation of gastrointestinal robotics trials should be based. We also discuss the emerging commercial landscape and define existing and new technologies.

Journal article

Zhao M, Oude Vrielink TJC, Kogkas A, Runciman M, Elson D, Mylonas Get al., 2020, LaryngoTORS: a novel cable-driven parallel robotic system for transoral laser phonosurgery, IEEE Robotics and Automation Letters, Vol: 5, Pages: 1516-1523, ISSN: 2377-3766

Transoral laser phonosurgery is a commonly used surgical procedure in which a laser beam is used to perform incision, ablation or photocoagulation of laryngeal tissues. Two techniques are commonly practiced: free beam and fiber delivery. For free beam delivery, a laser scanner is integrated into a surgical microscope to provide an accurate laser scanning pattern. This approach can only be used under direct line of sight, which may cause increased postoperative pain to the patient and injury, is uncomfortable for the surgeon during prolonged operations, the manipulability is poor and extensive training is required. In contrast, in the fiber delivery technique, a flexible fiber is used to transmit the laser beam and therefore does not require direct line of sight. However, this can only achieve manual level accuracy, repeatability and velocity, and does not allow for pattern scanning. Robotic systems have been developed to overcome the limitations of both techniques. However, these systems offer limited workspace and degrees-of-freedom (DoF), limiting their clinical applicability. This work presents the LaryngoTORS, a robotic system that aims at overcoming the limitations of the two techniques, by using a cable-driven parallel mechanism (CDPM) attached at the end of a curved laryngeal blade for controlling the end tip of the laser fiber. The system allows autonomous generation of scanning patterns or user driven freepath scanning. Path scan validation demonstrated errors as low as 0.054±0.028 mm and high repeatability of 0.027±0.020 mm (6×2 mm arc line). Ex vivo tests on chicken tissue have been carried out. The results show the ability of the system to overcome limitations of current methods with high accuracy and repeatability using the superior fiber delivery approach.

Journal article

Runciman M, Avery J, Zhao M, Darzi A, Mylonas GPet al., 2020, Deployable, variable stiffness, cable driven robot for minimally invasive surgery, Frontiers in Robotics and AI, Vol: 6, Pages: 1-16, ISSN: 2296-9144

Minimally Invasive Surgery (MIS) imposes a trade-off between non-invasive access and surgical capability. Treatment of early gastric cancers over 20 mm in diameter can be achieved by performing Endoscopic Submucosal Dissection (ESD) with a flexible endoscope; however, this procedure is technically challenging, suffers from extended operation times and requires extensive training. To facilitate the ESD procedure, we have created a deployable cable driven robot that increases the surgical capabilities of the flexible endoscope while attempting to minimize the impact on the access that they offer. Using a low-profile inflatable support structure in the shape of a hollow hexagonal prism, our robot can fold around the flexible endoscope and, when the target site has been reached, achieve a 73.16% increase in volume and increase its radial stiffness. A sheath around the variable stiffness structure delivers a series of force transmission cables that connect to two independent tubular end-effectors through which standard flexible endoscopic instruments can pass and be anchored. Using a simple control scheme based on the length of each cable, the pose of the two instruments can be controlled by haptic controllers in each hand of the user. The forces exerted by a single instrument were measured, and a maximum magnitude of 8.29 N observed along a single axis. The working channels and tip control of the flexible endoscope remain in use in conjunction with our robot and were used during a procedure imitating the demands of ESD was successfully carried out by a novice user. Not only does this robot facilitate difficult surgical techniques, but it can be easily customized and rapidly produced at low cost due to a programmatic design approach.

Journal article

Zhao M, Oude Vrielink J, Kogkas A, Runciman M, Elson D, Mylonas Get al., 2020, LaryngoTORS: A Novel Cable-Driven Parallel Robot for Transoral Laser Surgery, International Conference on Robotics and Automation (ICRA)

Conference paper

Zhao M, Zhang H, Mylonas GP, Elson DSet al., 2020, Cable-driven parallel robot assisted confocal imaging of the larynx

LaryngoTORS, a transoral laryngeal surgery robot, can manipulate instruments accurately. Confocal imaging has potentials in laryngeal cancer diagnosis but suffer from high scanning requirement. This work studies using LaryngoTORS to assist confocal imaging of larynx.

Conference paper

Ezzat A, Thakkar R, Kogkas A, Mylonas Get al., 2019, Perceptions of surgeons and scrub nurses towards a novel eye-tracking based robotic scrub nurse platform, International Surgical Congress of the Association-of-Surgeons-of-Great-Britain-and-Ireland (ASGBI), Publisher: WILEY, Pages: 81-82, ISSN: 0007-1323

Conference paper

Avery J, Runciman M, Darzi A, Mylonas GPet al., 2019, Shape sensing of variable stiffness soft robots using electrical impedance tomography, International Conference on Robotics and Automation (ICRA), Publisher: IEEE, Pages: 9066-9072, ISSN: 1050-4729

Soft robotic systems offer benefits over traditional rigid systems through reduced contact trauma with soft tissues and by enabling access through tortuous paths in minimally invasive surgery. However, the inherent deformability of soft robots places both a greater onus on accurate modelling of their shape, and greater challenges in realising intraoperative shape sensing. Herein we present a proprioceptive (self-sensing) soft actuator, with an electrically conductive working fluid. Electrical impedance measurements from up to six electrodes enabled tomographic reconstructions using Electrical Impedance Tomography (EIT). A new Frequency Division Multiplexed (FDM) EIT system was developed capable of measurements of 66 dB SNR with 20 ms temporal resolution. The concept was examined in two two-degree-of-freedom designs: a hydraulic hinged actuator and a pneumatic finger actuator with hydraulic beams. Both cases demonstrated that impedance measurements could be used to infer shape changes, and EIT images reconstructed during actuation showed distinct patterns with respect to each degree of freedom (DOF). Whilst there was some mechanical hysteresis observed, the repeatability of the measurements and resultant images was high. The results show the potential of FDM-EIT as a low-cost, low profile shape sensor in soft robots.

Conference paper

Runciman M, Darzi A, Mylonas G, 2019, Soft robotics in minimally invasive surgery, Soft Robotics, Vol: 6, Pages: 423-443, ISSN: 2169-5172

Soft robotic devices have desirable traits for applications in minimally invasive surgery (MIS) but many interdisciplinary challenges remain unsolved. To understand current technologies, we carried out a keyword search using the Web of Science and Scopus databases, applied inclusion and exclusion criteria, and compared several characteristics of the soft robotic devices for MIS in the resulting articles. There was low diversity in the device designs and a wide-ranging level of detail regarding their capabilities. We propose a standardised comparison methodology to characterise soft robotics for various MIS applications, which will aid designers producing the next generation of devices.

Journal article

Fathi J, Vrielink TJCO, Runciman MS, Mylonas GPet al., 2019, A Deployable Soft Robotic Arm with Stiffness Modulation for Assistive Living Applications, International Conference on Robotics and Automation (ICRA), Publisher: IEEE, Pages: 1479-1485, ISSN: 1050-4729

Conference paper

Patel N, Kogkas A, Ben Glover AD, Mylonas Get al., 2019, EYE GAZE-CONTROLLED ROBOTIC FLEXIBLE ENDOSCOPY: A FEASIBILITY STUDY, Annual Meeting of the British-Society-of-Gastroenterology (BSG), Publisher: BMJ PUBLISHING GROUP, Pages: A38-A39, ISSN: 0017-5749

Conference paper

Vrielink TJCO, Puyal JG-B, Kogkas A, Darzi A, Mylonas Get al., 2019, Intuitive gaze-control of a robotized flexible endoscope, 25th IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), Publisher: IEEE, Pages: 1776-1782, ISSN: 2153-0858

Flexible endoscopy is a routinely performed procedure that has predominantly remained unchanged for decades despite its many challenges. This paper introduces a novel, more intuitive and ergonomic platform that can be used with any flexible endoscope, allowing easier navigation and manipulation. A standard endoscope is robotized and a gaze control system based on eye-tracking is developed and implemented, allowing hands-free manipulation. The system characteristics and step response has been evaluated using visual servoing. Further, the robotized system has been compared with a manually controlled endoscope during a user study. The users (n=11) showed a preference for the gaze controlled endoscope and a lower task load when the task was performed with the gaze control. In addition, gaze control was related to a higher success rate and a lower time to perform the task. The results presented validate the system's technical performance and demonstrate the intuitiveness of hands-free gaze control in flexible endoscopy.

Conference paper

Wang M-Y, Kogkas AA, Darzi A, Mylonas GPet al., 2019, Free-view, 3D gaze-guided, assistive robotic system for activities of daily living, 25th IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), Publisher: IEEE, Pages: 2355-2361, ISSN: 2153-0858

Patients suffering from quadriplegia have limited body motion which prevents them from performing daily activities. We have developed an assistive robotic system with an intuitive free-view gaze interface. The user's point of regard is estimated in 3D space while allowing free head movement and is combined with object recognition and trajectory planning. This framework allows the user to interact with objects using fixations. Two operational modes have been implemented to cater for different eventualities. The automatic mode performs a pre-defined task associated with a gaze-selected object, while the manual mode allows gaze control of the robot's end-effector position on the user's frame of reference. User studies reported effortless operation in automatic mode. A manual pick and place task achieved a success rate of 100% on the users' first attempt.

Conference paper

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