Robotic-assisted surgery in ophthalmology

Transforming the future of ophthalmology: artificial intelligence and robotics' breakthrough role in surgical and medical retina advances: a mini review

Over the past decade, artificial intelligence (AI) and its subfields, deep learning and machine learning, have become integral parts of ophthalmology, particularly in the field of ophthalmic imaging. A diverse array of algorithms has emerged to facilitate the automated diagnosis of numerous medical and surgical retinal conditions. The development of these algorithms necessitates extensive training using large datasets of retinal images. This approach has demonstrated a promising impact, especially in increasing accuracy of diagnosis for unspecialized clinicians for various diseases and in the area of telemedicine, where access to ophthalmological care is restricted. In parallel, robotic technology has made significant inroads into the medical field, including ophthalmology. The vast majority of research in the field of robotic surgery has been focused on anterior segment and vitreoretinal surgery. These systems offer potential improvements in accuracy and address issues such as hand tremors. However, widespread adoption faces hurdles, including the substantial costs associated with these systems and the steep learning curve for surgeons. These challenges currently constrain the broader implementation of robotic surgical systems in ophthalmology. This mini review discusses the current research and challenges, underscoring the limited yet growing implementation of AI and robotic systems in the field of retinal conditions.

Robotising vitreoretinal surgeries

The use of robotic surgery in ophthalmology has been shown to offer many potential advantages to current surgical techniques. Vitreoretinal surgery requires complex manoeuvres and high precision, and this is an area that exceeds manual human dexterity in certain surgical situations. With the advent of advanced therapeutics such as subretinal gene therapy, precise delivery and minimising trauma is imperative to optimize outcomes. There are multiple robotic systems in place for ophthalmology in pre-clinical and clinical use, and the Preceyes Robotic Surgical System (Preceyes BV) has also gained the CE mark and is commercially available for use. Recent in-vivo and in-human surgeries have been performed successfully with robotics systems. This includes membrane peeling, subretinal injections of therapeutics, and retinal vein cannulation. There is huge potential to integrate robotic surgery into mainstream clinical practice. In this review, we summarize the existing systems, and clinical implementation so far, and highlight the future clinical applications for robotic surgery in vitreo-retina.

Efficacy and safety of a neurointerventional operation robotic assistance system in cerebral angiography

BACKGROUND

At present, neurointerventional surgery requires angiographers to perform operations in the digital subtraction angiography (DSA) room. Ionising radiation and chronic joint damage are still unavoidable for angiographers. Therefore, we researched and developed a neurointerventional robot-assisted system, which is operated by angiographers in an operating room outside the DSA room. We have conducted a prospective, multicentre, randomised controlled trial to evaluate the safety and efficacy of a robot-assisted system in human cerebral angiography. In the future, this research will provide a platform for the research and development of an intelligent surgical system and bring revolutionary progress in neurointerventional surgery.

METHODS

From December 2020 to December 2021, 260 patients were enrolled from three medical centres, who were randomly and equally divided into a robot-assisted system group and a clinical routine cerebral angiography group. The success rate of angiography, the rate of the catheter reaching the target vessel, the operation time, X-ray radiation exposure and the incidence of related adverse events were compared between the two groups.

RESULTS

A total of 257 patients completed this trial; baseline characteristics of the two groups did not differ significantly. The success rate of angiography in both the control group and the experimental group was 100%. The rate of the catheter reaching the target vessel was 99.23% and 100.00% in the control and experimental groups, respectively. For the control versus experimental groups, the angiographic operation time was 48.59±25.60 min versus 47.94±27.49 min, respectively; the X-ray radiation dose was 735.01±554.77 mGy versus 821.65±705.45 mGy, respectively; and the incidence of adverse events was 23.44% versus 22.48%, respectively. No statistical differences were present between the two groups.

CONCLUSION

The robot-assisted surgical system is more convenient for cerebral angiography and is as safe and effective as the traditional cerebral angiography.

Unveiling the Potential: A Comprehensive Review of Artificial Intelligence Applications in Ophthalmology and Future Prospects

Artificial intelligence (AI) has emerged as a transformative force in healthcare, particularly in the field of ophthalmology. This comprehensive review examines the current applications of AI in ophthalmology, highlighting its significant contributions to diagnostic accuracy, treatment efficacy, and patient care. AI technologies, such as deep learning algorithms, have demonstrated exceptional performance in the early detection and diagnosis of various eye conditions, including diabetic retinopathy (DR), age-related macular degeneration (AMD), and glaucoma. Additionally, AI has enhanced the analysis of ophthalmic imaging techniques like optical coherence tomography (OCT) and fundus photography, facilitating more precise disease monitoring and management. The review also explores AI's role in surgical assistance, predictive analytics, and personalized treatment plans, showcasing its potential to revolutionize clinical practice and improve patient outcomes. Despite these advancements, challenges such as data privacy, regulatory hurdles, and ethical considerations remain. The review underscores the need for continued research and collaboration among clinicians, researchers, technology developers, and policymakers to address these challenges and fully harness the potential of AI in improving eye health worldwide. By integrating AI with teleophthalmology and developing AI-driven wearable devices, the future of ophthalmic care promises enhanced accessibility, efficiency, and efficacy, ultimately reducing the global burden of visual impairment and blindness.

Sharper vision, steady hands: can robots improve subretinal drug delivery? Systematic review

Subretinal injection (SI) is a novel drug delivery method, directly to retina for treatment of various eye disease. However, manual injection requires surgical experience and precision due to physiological factors. Robots offer solution to this issue, by reducing hand tremor and increased accuracy. This systematic review analyzes current status on robot-assisted SI compared to conventional techniques. Systematic search across 5 databases was conducted to identify studies comparing manual and robot-assisted SI procedures. Extracted data included robotic systems, complications, and success rates. Four studies, including one human trial, two ex vivo porcine eye studies, and one artificial eye model study were included in the synthesis. The findings show early advantages of robot-assisted SI. Compared to traditional interventions, robot procedures result in reduced tremor, what potentially lowers the risk of complications, including retinal tears and reflux. The first in-human randomized trial showed encouraging results, with no significant differences in surgical times or complications between robot-assisted and manual SI. However, major limitation of robot-assisted procedures is longer procedure time. Robot-assisted SI holds promise by offering increased precision and stability, reducing human error and potentially improving clinical outcomes. Challenges include cost, availability, and learning curve. Overall, early stage of robot-assisted SI suggests advantages in precision, complication reduction, and potentially improved drug delivery. Further research in human randomized trials is needed to fully assess its full-scale clinical application.

A Review of Recent Advancements in Sensor-Integrated Medical Tools

A medical tool is a general instrument intended for use in the prevention, diagnosis, and treatment of diseases in humans or other animals. Nowadays, sensors are widely employed in medical tools to analyze or quantify disease-related parameters for the diagnosis and monitoring of patients' diseases. Recent explosive advancements in sensor technologies have extended the integration and application of sensors in medical tools by providing more versatile in vivo sensing capabilities. These unique sensing capabilities, especially for medical tools for surgery or medical treatment, are getting more attention owing to the rapid growth of minimally invasive surgery. In this review, recent advancements in sensor-integrated medical tools are presented, and their necessity, use, and examples are comprehensively introduced. Specifically, medical tools often utilized for medical surgery or treatment, for example, medical needles, catheters, robotic surgery, sutures, endoscopes, and tubes, are covered, and in-depth discussions about the working mechanism used for each sensor-integrated medical tool are provided.

Review of robotic surgery platforms and end effectors

In the last 50 years, the number of companies producing automated devices for surgical operations has grown extensively. The population started to be more confident about the technology capabilities. The first patents related to surgical robotics are expiring and this knowledge is becoming a common base for the development of future surgical robotics. The review describes some of the most popular companies manufacturing surgical robots. The list of the company does not pretend to be exhaustive but wishes to give an overview of the sector. Due to space constraints, only a limited selction of companies is reported. Most of the companies described are born in America or Europe. Advantages and limitations of each product firm are described. A special focus is given to the end effectors; their shape and dexterity are crucial for the positive outcome of the surgical operations. New robots are developed every year, and existing robots are allowed to perform a wider range of procedures. Robotic technologies improve the abilities of surgeons in the domains of urology, gynecology, neurology, spine surgery, orthopedic reconstruction (knee, shoulder), hair restoration, oral surgery, thoracic surgery, laparoscopic surgery, and endoscopy.

Steady-Hand Eye Robot 3.0: Optimization and Benchtop Evaluation for Subretinal Injection

Subretinal injection methods and other procedures for treating retinal conditions and diseases (many considered incurable) have been limited in scope due to limited human motor control. This study demonstrates the next generation, cooperatively controlled Steady-Hand Eye Robot (SHER 3.0), a precise and intuitive-to-use robotic platform achieving clinical standards for targeting accuracy and resolution for subretinal injections. The system design and basic kinematics are reported and a deflection model for the incorporated delta stage and validation experiments are presented. This model optimizes the delta stage parameters, maximizing the global conditioning index and minimizing torsional compliance. Five tests measuring accuracy, repeatability, and deflection show the optimized stage design achieves a tip accuracy of < 30 μm, tip repeatability of 9.3 μm and 0.02°, and deflections between 20-350 μm/N. Future work will use updated control models to refine tip positioning outcomes and will be tested on in vivo animal models.

The State of Intraoperative OCT in Vitreoretinal Surgery: Recent Advances and Future Challenges

Since its first introduction more than 30 years ago, optical coherence tomography (OCT) has revolutionized ophthalmology practice, providing a non-invasive in vivo cross-sectional view of the structures of the eye. Mostly employed in the clinical setting due to its tabletop configuration requiring an upright patient positioning, the recent advent of microscope-integrated systems now allows ophthalmologists to perform real-time intraoperative OCT (iOCT) during vitreoretinal surgical procedures. Numerous studies described various applications of this tool, such as offering surgeons feedback on tissue-instrument interactions in membrane peeling, providing structural images in macular hole repair, and showing residual subretinal fluid or perfluorocarbon in retinal detachment surgery. This narrative review aims at describing the state of the art of iOCT in vitreoretinal procedures, highlighting its modern role and applications in posterior segment surgery, its current limitations, and the future perspectives that may improve the widespread adoption of this technology.

Robot-Assisted Epiretinal Membrane Peeling: A Prospective Assessment of Pre- and Intra-Operative Times and of Surgeons' Subjective Perceptions

PURPOSE

The Preceyes Surgical System (PSS) is a robotic assistive device that may enhance surgical precision. This study assessed pre- and intra-operative times and surgeons' perceptions of robot-assisted epiretinal membrane peeling (RA-MP).

METHODS

We analyzed the time requirement of three main tasks: the preparation of the PSS (I), patient preparation (II), and surgery (III). Following surgery, the surgeons were asked questions about their experience.

RESULTS

RA-MP was performed in nine eyes of nine patients. Task I required an average time of 12.3 min, initially taking 15 min but decreasing to 6 min in the last surgery. Task II showed a mean time of 47.2 (range of 36-65) min. Task III had a mean time of 72.4 (range of 57-100) min. A mean time of 27.9 (range of 9-46) min was necessary for RA-MP. The responses to the questionnaire revealed a trend towards increasing ease and reduced stress as familiarity with the PSS increased.

CONCLUSIONS

A substantial reduction in pre- and intra-operative times, decreasing to a total of 115 min, was demonstrated. RA-MP was positively anticipated by the surgeons and led to no hand or arm strain while being more complex than manual MP.

Robotics and cybersurgery in ophthalmology: a current perspective

Ophthalmology is one of the most enriched fields, allowing the domain of artificial intelligence to be part of its point of interest in scientific research. The requirement of specialized microscopes and visualization systems presents a challenge to adapting robotics in ocular surgery. Cyber-surgery has been used in other surgical specialties aided by Da Vinci robotic system. This study focuses on the current perspective of using robotics and cyber-surgery in ophthalmology and highlights factors limiting their progression. A review of literature was performed with the aid of Google Scholar, Pubmed, CINAHL, MEDLINE (N.H.S. Evidence), Cochrane, AMed, EMBASE, PsychINFO, SCOPUS, and Web of Science. Keywords: Cybersurgery, Telesurgery, ophthalmology robotics, Da Vinci robotic system, artificial intelligence in ophthalmology, training on robotic surgery, ethics of the use of robots in medicine, legal aspects, and economics of cybersurgery and robotics. 150 abstracts were reviewed for inclusion, and 68 articles focusing on ophthalmology were included for full-text review. Da Vinci Surgical System has been used to perform a pterygium repair in humans and was successful in ex vivo corneal, strabismus, amniotic membrane, and cataract surgery. Gamma Knife enabled effective treatment of uveal melanoma. Robotics used in ophthalmology were: Da Vinci Surgical System, Intraocular Robotic Interventional Surgical System (IRISS), Johns Hopkins Steady-Hand Eye Robot and smart instruments, and Preceyes' B.V. Cybersurgery is an alternative to overcome distance and the shortage of surgeons. However, cost, availability, legislation, and ethics are factors limiting the progression of these fields. Robotic and cybersurgery in ophthalmology are still in their niche. Cost-effective studies are needed to overcome the delay. Technologies, such as 5G and Tactile Internet, are required to help reduce resource scheduling problems in cybersurgery. In addition, prototype development and the integration of artificial intelligence applications could further enhance the safety and precision of ocular surgery.

Robot-Assisted Surgery in Gynecology

The advancement of robotics-based procedures in the medical industry is the subject of this review article. The purpose of the surgical robot is to increase surgical abilities and address human shortcomings. The robot's success has been predicated on its ability to accurately and consistently repeat tasks. The following are a few objectives and quantifiable benefits of robotic technology improving surgical maneuverability and physical capabilities. In 2005, the FDA granted gynecological surgery approval for the Da Vinci surgical system. It has been quickly embraced and has already taken on a significant role at many of the locations where it is offered. It consists of a cart with robotic branches next to the patient and a high-resolution three-dimensional (3D) vision system. This study covers laparoscopy via robots in benign gynecological surgeries, myomectomy surgery, hysterectomies, endometriosis, tubal anastomosis, and sacrocolpopexy. The appropriate published studies were evaluated after a PubMed search was conducted. Additionally, procedures that may be used in the future are highlighted. In benign gynecological illness, most currently available research does not show a substantial benefit over traditional laparoscopic surgery. Robotics, however, does provide help in more complicated operations. Compared to laparoscopy, robotic assistance has a lower conversion rate to open procedures. Endo wrist movement of an automated machine during myomectomy surgery can perform proper and better suturing than traditional laparoscopy. The automated program is a noticeable improvement over laparoscopic surgery and, if price issues are resolved, can gain popularity among gynecological surgeons around the globe.

A Novel Microsurgical Robot: Preliminary Feasibility Test in Ophthalmic Field

Purpose

This study investigated the feasibility and potential advantage of using a new microsurgical teleoperated robot, Symani Surgical System, in the ophthalmology field. In particular, considering the extreme precision of the system and the dexterity of the instrument, possible use of the Symani Surgical System has been explored for suturing in corneal graft surgery.

Methods

Manual and robot-assisted suturing of partial corneal transplants was performed on the porcine eye model by an ophthalmologist with experience with the porcine model. Suturing execution time, suture placement, and tomographic parameters were analyzed to assess the regularity and distribution of corneal sutures for both manual and robotic treatment.

Results

The two robot-assisted procedures were properly completed on the porcine model, confirming the ease of use of the system and its capabilities, as well as the dexterity of the microinstruments. Manual and robotic treatments were found to be equivalent in terms of distance and angular precision of suture placement and corneal surface regularity (Gaussian anterior curvature). The robotic procedure required longer suturing execution times compared with the manual procedure.

Conclusions

The technical and clinical feasibility of robot-assisted suturing of partial corneal graft using the Symani Surgical System has been confirmed for the first time, to our knowledge, using an ex vivo porcine model. Robotic suturing required longer time to complete but was equivalent to the manual procedure with regard to the imaging data collected.

Translational Relevance

This study evaluated the use of the Symani Surgical System in the ophthalmology field. Future investigations could further identify the advantages offered by the stability, dexterity, and motion precision of the system for corneal surgeries, paving the way for clinical use in both adult and even more challenging pediatric therapy.

Robotic Assistance for Intraocular Microsurgery: Challenges and Perspectives

Intraocular surgery, one of the most challenging discipline of microsurgery, requires sensory and motor skills at the limits of human physiological capabilities combined with tremendously difficult requirements for accuracy and steadiness. Nowadays, robotics combined with advanced imaging has opened conspicuous and significant directions in advancing the field of intraocular microsurgery. Having patient treatment with greater safety and efficiency as the final goal, similar to other medical applications, robotics has a real potential to fundamentally change microsurgery by combining human strengths with computer and sensor-based technology in an information-driven environment. Still in its early stages, robotic assistance for intraocular microsurgery has been accepted with precaution in the operating room and successfully tested in a limited number of clinical trials. However, owing to its demonstrated capabilities including hand tremor reduction, haptic feedback, steadiness, enhanced dexterity, micrometer-scale accuracy, and others, microsurgery robotics has evolved as a very promising trend in advancing retinal surgery. This paper will analyze the advances in retinal robotic microsurgery, its current drawbacks and limitations, as well as the possible new directions to expand retinal microsurgery to techniques currently beyond human boundaries or infeasible without robotics.

Robotics in Vitreo-Retinal Surgery

PURPOSE

Modern vitreo-retinal surgery has scaled new frontiers with the advent of better instrumentation. However, physiological tremors, intraocular dexterity and difficulty in visualization hamper minimally invasive retinal surgery. Robotics has the potential to overcome these limitations and improve surgical outcomes. This review aims to provide a comprehensive summary of the advances made in the field of robotics in vitreo-retinal surgery.

METHODS

This review included 30 studies comprising randomized control trials, nonrandomized comparative studies and systematic reviews on the application of robotics in vitreo-retinal surgery.

RESULTS

Robotic systems presently available in vitreo-retinal surgery can be broadly classified based on the extent of automation into five categories: robot-assisted, co-manipulated, tele-operated, partially/fully automated and magnetically controlled devices. Key features of individual devices are highlighted in this review. Robotic assistance in vitreo-retinal surgery can maximize performance for routine procedures, enable high-precision procedures such as targeted gene therapy and retinal vein cannulation, improve ergonomics, and revolutionize tele-surgery. Cost limitations and compatibility with available surgical systems are the barriers in implementation of robotics in retinal microsurgery.

CONCLUSION

This review provides a concise summary of the available robotic systems in vitreo-retinal surgery, advantages over conventional systems, current applications and future implications. Robotics is a rapidly evolving field, which holds great promise in the future of vitreo-retinal surgery.

First-in-Human Robot-Assisted Subretinal Drug Delivery Under Local Anesthesia

PURPOSE

To report the results of a first-in-human study using a robotic device to assist subretinal drug delivery in patients undergoing vitreoretinal surgery for macular hemorrhage.

DESIGN

Double-armed, randomized controlled surgical trial (ClinicalTrials.gov identifier: NCT03052881).

METHODS

The study was performed at the Oxford Eye Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom. In total, 12 participants were recruited-6 in the robot-assisted and 6 in the control manual surgery arm according to the prespecified inclusion and exclusion criteria. All subjects presented with acute loss of vision owing to a subfoveal hemorrhage secondary to neovascular age-related macular degeneration. After standard vitrectomy, intraoperative optical coherence tomography-guided subretinal injection of tissue plasminogen activator (TPA) was performed by either robot-assisted or conventional manual technique under local anesthesia. The robotic part of the procedure involved advancement of a cannula through the retina and stabilizing it during foot-controlled injection of up to 100 µL of TPA solution. We assessed surgical success, duration of surgery, adverse events, and tolerability of surgery under local anesthesia.

RESULTS

The procedure was well tolerated by all participants and safely performed in all cases. Total duration of surgery, time taken to complete the injection, and retinal microtrauma were similar between the groups and not clinically significant. Subretinal hemorrhage was successfully displaced at 1 month postintervention, except for 1 control subject, and the median gain in visual acuity was similar in both arms.

CONCLUSIONS

This first-in-human study demonstrates the feasibility and safety of high-precision robot-assisted subretinal drug delivery as part of the surgical management of submacular hemorrhage, simulating its potential future application in gene or cell therapy.

Subretinal Therapy: Technological Solutions to Surgical and Immunological Challenges

Recent advances in ocular gene and cellular therapy rely on precisely controlled subretinal delivery. Due to its inherent limitations, manual delivery can lead to iatrogenic damage to the retina, the retinal pigment epithelium, favor reflux into the vitreous cavity. In addition, it suffers from lack of standardization, variability in delivery and the need to maintain proficiency. With or without surgical damage, an eye challenged with an exogenous viral vector or transplanted cells will illicit an immune response. Understanding how such a response manifests itself and to what extent immune privilege protects the eye from a reaction can help in anticipating short- and long-term consequences. Avoidance of spillover from areas of immune privilege to areas which either lack or have less protection should be part of any mitigation strategy. In that regard, robotic technology can provide reproducible, standardized delivery which is not dependent on speed of injection. The advantages of microprecision medical robotic technology for precise targeted deliveries are discussed.

Three-dimensional telesurgery and remote proctoring over a 5G network

Purpose

To present 2 cases of vitreoretinal surgery performed on a three-dimensional (3D) heads-up display surgical platform with real-time transfer of 3D video over a fifth-generation (5G) cellular network.

Methods

An epiretinal membrane peel and tractional retinal detachment repair performed at Massachusetts Eye and Ear in April 2019 were broadcast live to the Verizon 5G Lab in Cambridge, MA.

Results

Both surgeries were successful. The heads-up digital surgery platform, combined with a 5G network, allowed telesurgical transfer of high-quality 3D vitreoretinal surgery with minimal degradation. Average end-to-end latency was 250 ms, and average round-trip latency was 16 ms. Fine surgical details were observed remotely by a proctoring surgeon and trainee, with real-time communication via mobile phone.

Conclusions

This pilot study represents the first successful demonstration of vitreoretinal surgery transmitted over a 5G network. Telesurgery has the potential to enhance surgical education, provide intraoperative consultation and guidance from expert proctors, and improve patient outcomes, especially in remote and low-resource areas.

Clinical Evaluation of an Instrument-Integrated OCT-Based Distance Sensor for Robotic Vitreoretinal Surgery

PURPOSE

To assess the efficacy of an instrument-integrated OCT (iiOCT)-based distance sensor during robotic vitreoretinal surgery using the Preceyes Surgical System (PSS; Preceyes B.V.).

DESIGN

Single-center interventional study.

PARTICIPANTS

Patients requiring vitreoretinal surgery.

METHODS

Five patients were enrolled. Standard preoperative OCT images were obtained. After vitrectomy, a predefined set of actions was performed using the iiOCT-based sensor. Images then were processed to assess the signal-to-noise ratio (SNR) at various angles to the retina and at different distances between the instrument tip and the retinal surface. Preoperative and intraoperative OCT images were compared qualitatively and quantitatively.

MAIN OUTCOMES MEASURES

The feasibility in performing surgical tasks using the iiOCT-based sensor during vitreoretinal surgery, the SNR when imaging the retina, differences among intraoperative and preoperative OCT images, and characteristics of intraoperative retinal movements detected with the iiOCT-based probe.

RESULTS

Surgeons were able to perform all the tasks but one. The PSS was able to maintain a fixed distance. The SNR of the iiOCT-based sensor signal was adequate to determine the distance to the retina and to control the PSS. Analysis of iiOCT-based sensor A-scans identified 3 clearly distinguishable retinal layers, including the inner retinal boundary and the interface at the retinal pigment epithelium-Bruch's membrane. Thickness values differed by less than 5% from that measured by preoperative OCT, indicating its accuracy. The Fourier analysis of iiOCT-based sensor recordings identified anteroposterior retinal movements attributed to heartbeat and respiration.

CONCLUSIONS

This iiOCT-based sensor was tested successfully and promises reliable use during robot-assisted surgery. An iiOCT-based sensor is a promising step toward OCT-guided robotic retinal surgery.

A review of robotic surgical training: establishing a curriculum and credentialing process in ophthalmology

Ophthalmic surgery requires a highly dexterous and precise surgical approach to work within the small confines of the eye, and the use of robotics offers numerous potential advantages to current surgical techniques. However, there is a lag in the development of a comprehensive training and credentialing system for robotic eye surgery, and certification of robotic skills proficiency relies heavily on industry leadership. We conducted a literature review on the curricular elements of established robotics training programs as well as privileging guidelines from various institutions to outline key components in training and credentialing robotic surgeons for ophthalmic surgeries. Based on our literature review and informal discussions between the authors and other robotic ophthalmic experts, we recommend that the overall training framework for robotic ophthalmic trainees proceeds in a stepwise, competency-based manner from didactic learning, to simulation exercises, to finally operative experiences. Nontechnical skills such as device troubleshooting and interprofessional teamwork should also be formally taught and evaluated. In addition, we have developed an assessment tool based on validated global rating scales for surgical skills that may be used to monitor the progress of trainees. Finally, we propose a graduating model for granting privileges to robotic surgeons. Further work will need to be undertaken to assess the feasibility, efficacy and integrity of the training curriculum and credentialing practices for robotic ophthalmic surgery.

Artificial intelligence and ophthalmic surgery

PURPOSE OF REVIEW

Artificial intelligence and deep learning have become important tools in extracting data from ophthalmic surgery to evaluate, teach, and aid the surgeon in all phases of surgical management. The purpose of this review is to highlight the ever-increasing intersection of computer vision, machine learning, and ophthalmic microsurgery.

RECENT FINDINGS

Deep learning algorithms are being applied to help evaluate and teach surgical trainees. Artificial intelligence tools are improving real-time surgical instrument tracking, phase segmentation, as well as enhancing the safety of robotic-assisted vitreoretinal surgery.

SUMMARY

Similar to strides appreciated in ophthalmic medical disease, artificial intelligence will continue to become an important part of surgical management of ocular conditions. Machine learning applications will help push the boundaries of what surgeons can accomplish to improve patient outcomes.

ROBOT-ASSISTED VITREORETINAL SURGERY IMPROVES SURGICAL ACCURACY COMPARED WITH MANUAL SURGERY: A Randomized Trial in a Simulated Setting

Robot-assisted vitreoretinal surgery increases precision and limits tissue damage compared with manual surgery especially for the novice surgeon. The Eyesi Simulator is a feasible platform for investigating robot-assisted vitreoretinal surgery.

Purpose:

To compare manual and robot-assisted vitreoretinal surgery using a virtual-reality surgical simulator.

Methods:

Randomized controlled crossover study. Ten experienced vitreoretinal surgeons and 10 novice ophthalmic surgeons were included. The participants were randomized to start with either manual or robot-assisted surgery. Participants completed a test session consisting of three vitreoretinal modules on the Eyesi virtual-reality simulator. The automated metrics of performance supplied by the Eyesi simulator were used as outcome measures. Primary outcome measures were time with instruments inserted (seconds), instrument movement (mm), and tissue treatment (mm²).

Results:

Robot-assisted surgery was slower than manual surgery for both novices and vitreoretinal surgeons, 0.24 SD units (P = 0.024) and 0.73 SD units (P < 0.001), respectively. Robot-assisted surgery allowed for greater precision in novices and vitreoretinal surgeons, −0.96 SD units (P < 0.001) and −0.47 SD units (P < 0.001), respectively. Finally, novices using robot-assisted surgery inflicted less tissue damage when compared with that using manual surgery, −0.59 SD units (P = 0.009).

Conclusion:

At the cost of time, robot-assisted vitreoretinal surgery seems to improve precision and limit tissue damage compared with that of manual surgery. In particular, the performance of novice surgeons is enhanced with robot-assisted vitreoretinal surgery.

Advantages of robotic assistance over a manual approach in simulated subretinal injections and its relevance for gene therapy

Subretinal injection is a method for gene delivery to treat genetic diseases of the photoreceptors and retinal pigment epithelium. A reflux-free subretinal injection is important to allow effective, safe, and cost-effective gene therapy to the retina. We report on a comparison between manual and robotic assistance in simulated subretinal injections using an artificial retina model. Nine surgeons carried out the procedure with and without the Preceyes Surgical System, using an OPMI Lumera 700 Zeiss surgical microscope equipped with intra-operative optical coherence tomography. Success in creating a bleb without reflux, injection duration, drift, tremor, and increase in the diameter of the puncture hole were analyzed. Robotic assistance improved drift (median 16 vs 212 µm), tremor (median 1 vs 18 µm), enlargement of the retinal hole, and allowed for prolonged injection times (median 52 vs 29 sec). Robotic assistance allowed higher rate of bleb formation (8/9 vs 4/9 attempts) with a moderate reduction in reflux (7/9 vs 8/9 attempts) in this artificial model. Robotic assistance can significantly contribute to subretinal injections and provide quantifiable parameters in assessing surgical and clinical success of novel retinal gene therapies.

Current methods for assessing technical skill in cataract surgery

Surgery is a major source of errors in patient care. Preventing complications from surgical errors in the operating room is estimated to lead to reduction of up to 41 846 readmissions and save $620.3 million per year. It is now established that poor technical skill is associated with an increased risk of severe adverse events postoperatively and traditional models to train surgeons are being challenged by rapid advances in technology, an intensified patient-safety culture, and a need for value-driven health systems. This review discusses the current methods available for evaluating technical skills in cataract surgery and the recent technological advancements that have enabled capture and analysis of large amounts of complex surgical data for more automated objective skills assessment.

Robotic Retinal Surgery Impacts on Scleral Forces: In Vivo Study

Purpose

This study aims to map force interaction between instrument and sclera of in vivo rabbits during retinal procedures, and verify if a robotic active force control could prevent unwanted increase of forces on the sclera.

Methods

Experiments consisted in the performance of intraocular movements of a force sensing instrument, adjacent to the retinal surface, in radial directions, from the center to the periphery and back, and compared manual manipulations with robotic assistance and also robotic assistance with an active force control. This protocol was approved by the Animal Use and Ethical Committee and experiments were according to ARVO Statement of Animal Use.

Results

Mean forces using manual manipulations were 115 ± 51 mN. Using robotic assistance, mean forces were 118 ± 49 mN. Using an active force control method, overall mean forces reduced to 69 ± 15, with a statistical difference compared with other methods (P < 0.001). Comparing intraocular directions, superior sector required higher forces and the force control method reduced differences in forces between users and retained the same force pattern between them.

Conclusions

Results validate that the introduction of robotic assistance might increase the dynamic interactions between instrument and sclera, and the addition of an active force control method reduces the forces at levels lower than manual manipulations.

Translational Relevance

All marketing benefits from extreme accuracy and stability from robots, however, redundancy of safety mechanisms during intraocular manipulations, especially on force control and surgical awareness, would allow all utility of robotic assistance in ophthalmology.

[What will cataract surgery look like in the future? Alternatives in the pipeline]

Phacoemulsification is the most frequently performed surgery in the world. Over the past few years, this surgery seems to have reached a plateau with no further innovative breakthroughs. In this paper, we focus on alternatives techniques, the latest innovations, and the research and development pipeline in this field.

Reducing the Number of Degrees of Freedom to Control an Eye Surgical Robot through Classification of Surgical Phases

This paper introduces an optimized input device workflow to control an eye surgical robot in a simulated vitreoretinal environment. The input device is a joystick with four Degrees of Freedom (DOF) that controls a six DOFs robot. This aim is achieved through a segmentation plan for an eye surgeon. In this study, the different surgical phases are defined while each phase includes their specific number of DOFs. The segmentation plan is divided into four surgical phases: Phase I: Approach with three DOFs; Phase II: Introduction with three DOFs; Phase III: Aim with 3+1 DOFs; and Phase IV: Injection with one DOF. Taking these phases into consideration, an eye surgical robot with six DOFs could be controlled through a joystick with only four DOFs intuitively. In this work we show that reducing the number of DOFs will decrease the complexity of the surgery with a robotic platform.

Artificial intelligence, robotics and eye surgery: are we overfitted?

Eye surgery, specifically retinal micro-surgery involves sensory and motor skill that approaches human boundaries and physiological limits for steadiness, accuracy, and the ability to detect the small forces involved. Despite assumptions as to the benefit of robots in surgery and also despite great development effort, numerous challenges to the full development and adoption of robotic assistance in surgical ophthalmology, remain. Historically, the first in-human-robot-assisted retinal surgery occurred nearly 30 years after the first experimental papers on the subject. Similarly, artificial intelligence emerged decades ago and it is only now being more fully realized in ophthalmology. The delay between conception and application has in part been due to the necessary technological advances required to implement new processing strategies. Chief among these has been the better matched processing power of specialty graphics processing units for machine learning. Transcending the classic concept of robots performing repetitive tasks, artificial intelligence and machine learning are related concepts that has proven their abilities to design concepts and solve problems. The implication of such abilities being that future machines may further intrude on the domain of heretofore "human-reserved" tasks. Although the potential of artificial intelligence/machine learning is profound, present marketing promises and hype exceeds its stage of development, analogous to the seventieth century mathematical "boom" with algebra. Nevertheless robotic systems augmented by machine learning may eventually improve robot-assisted retinal surgery and could potentially transform the discipline. This commentary analyzes advances in retinal robotic surgery, its current drawbacks and limitations, and the potential role of artificial intelligence in robotic retinal surgery.

Human/robotic interaction: vision limits performance in simulated vitreoretinal surgery

PURPOSE

Compare accuracy and precision in XYZ of stationary and dynamic tasks performed by surgeons with and without the use of a tele-operated robotic micromanipulator in a simulated vitreoretinal environment. The tasks were performed using a surgical microscope or while observing a video monitor.

METHOD

Two experienced and two novice surgeons performed tracking and static tasks at a fixed depth with hand-held instruments on a Preceyes Surgical System R0.4. Visualization was through a standard microscope or a video display. The distances between the instrument tip and the targets (in μm) determined tracking errors in accuracy and precision.

RESULTS

Using a microscope, dynamic or static accuracy and precision in XY (planar) movements were similar among test subjects. In Z (depth) movements, experience lead to more precision in both dynamic and static tasks (dynamic 35 ± 14 versus 60 ± 37 μm; static 27 ± 8 versus 36 ± 10 μm), and more accuracy in dynamic tasks (58 ± 35 versus 109 ± 79 μm). Robotic assistance improved both precision and accuracy in Z (1-3 ± 1 μm) in both groups. Using a video screen in combination with robotic assistance improved all performance measurements and reduced any differences due to experience.

CONCLUSIONS

Robotics increases precision and accuracy, with greater benefit observed in less experienced surgeons. However, human control was a limiting factor in the achieved improvement. A major limitation was visualization of the target surface, in particular in depth. To maximize the benefit of robotic assistance, visualization must be optimized.

Robotics and ophthalmology: Are we there yet?

Ophthalmology is a field that is now seeing the integration of robotics in its surgical procedures and interventions. Assistance facilitated by robots offers substantial improvements in terms of movement control, tremor cancellation, enhanced visualization, and distance sensing. Robotic technology has only recently been integrated into ophthalmology; hence, the progression is only in its initial stages. Robotic technologies such as da Vinci Surgical System are integrated into the field of ophthalmology and are assisting surgeons in complex eye surgeries. Ophthalmic surgeries require high accuracy and precision to execute tissue manipulation, and some complex ocular surgery may take few hours to complete the procedures that may predispose high-volume ophthalmic surgeons to work-related musculoskeletal disorders. A complete paradigm shift has been achieved in this particular field through the integration of advanced robotic technology, resulting in easier and more efficient procedures. Where robotic technology assists the surgeons and improves the overall quality of care, it also projects several challenges including limited availability, training, and the high cost of the robotic system. Although considerable studies and trials have been conducted for various robotic systems, only a few of them have made it to the commercial stage and ophthalmology, on its own, has a long way to go in robotics technology.

The Effect of Haptic Feedback on Efficiency and Safety During Preretinal Membrane Peeling Simulation

Purpose

We determine whether haptic feedback improves surgical performance and outcome during simulated a preretinal membrane peeling procedure.

Methods

A haptic-enabled virtual reality preretinal membrane peeling simulator was developed using a surgical cockpit with two multifinger haptic devices. Six subjects (three trained retina surgeons and three nonsurgeons) performed the preretinal membrane peeling surgical procedure using two modes of operation: visual and haptic feedback, and visual feedback only.

Results

Task completion time, tool tip path trajectory, tool–retina collision force, and retinal damage were all reduced with haptic feedback used and compared to modes where haptic feedback was disabled.

Conclusions

Haptic feedback improves efficiency and safety during preretinal membrane peeling simulation.

Translational Relevance

These findings highlight the potential benefit of haptic feedback for improving performance and safety of vitreoretinal surgery.

Endoscopic vitreoretinal surgery: principles, applications and new directions

Purpose

To analyze endoscopic vitreoretinal surgery principles, applications, challenges and potential technological advances.

Background

Microendoscopic imaging permits vitreoretinal surgery for tissues that are not visible using operating microscopy ophthalmoscopy. Evolving instrumentation may overcome some limitations of current endoscopic technology.

Analysis

Transfer of the fine detail in endoscopic vitreoretinal images to extraocular video cameras is constrained currently by the caliber limitations of intraocular probes in ophthalmic surgery. Gradient index and Hopkins rod lenses provide high resolution ophthalmoscopy but restrict surgical manipulation. Fiberoptic coherent image guides offer surgical maneuverability but reduce imaging resolution. Coaxial endoscopic illumination can highlight delicate vitreoretinal structures difficult to image in chandelier or endoilluminator diffuse, side-scattered lighting. Microendoscopy’s ultra-high magnification video monitor images can reveal microscopic tissue details blurred partly by ocular media aberrations in contemporary surgical microscope ophthalmoscopy, thereby providing a lower resolution, invasive alternative to confocal fundus imaging. Endoscopic surgery is particularly useful when ocular media opacities or small pupils restrict or prevent transpupillary ophthalmoscopy. It has a growing spectrum of surgical uses that include the management of proliferative vitreoretinopathy and epiretinal membranes as well as the implantation of posterior chamber intraocular lenses and electrode arrays for intraretinal stimulation in retinitis pigmentosa. Microendoscopy’s range of applications will continue to grow with technological developments that include video microchip sensors, stereoscopic visualization, chromovitrectomy, digital image enhancement and operating room heads-up displays.

Conclusion

Microendoscopy is a robust platform for vitreoretinal surgery. Continuing clinical and technological innovation will help integrate it into the modern ophthalmic operating room of interconnected surgical microscopy, microendoscopy, vitrectomy machine and heads-up display instrumentation.

Robot-Assisted Simulated Strabismus Surgery

Purpose

This study aims to investigate the feasibility of robot-assisted simulated strabismus surgery using the new da Vinci Xi Surgical System and to report what we believe is the first use of a surgical robot in experimental eye muscle surgery.

Methods

Robot-assisted strabismus surgeries were performed on a strabismus eye model using the robotic da Vinci Xi Surgical System. On the lateral rectus of each eye, we performed a procedure including, successively, a 4-mm plication followed by a 4-mm recession of the muscle to end with a 4-mm resection. Operative time from conjunctival opening to closing and successful completion of the different steps with or without complications or unexpected events were assessed.

Results

Robot-assisted strabismus procedures were successfully performed on six eyes. The feasibility of robot-assisted simulated strabismus surgery is confirmed. The da Vinci Xi system provided the appropriate dexterity and operative field visualization necessary to perform conjunctival and Tenon's capsule opening and closing, muscle identification, suturing, desinsertion, sectioning, and resuturing. The mean duration to complete the whole procedure was 27 minutes (range, 22–35). There were no complications or unexpected intraoperative events.

Conclusions

Experimental robot-assisted strabismus surgery is technically feasible using the new robotic da Vinci Xi Surgical System. This is, to our knowledge, the first use of a surgical robot in ocular muscle surgery.

Translational Relevance

Further experimentation will allow the advantages of robot-assisted microsurgery to be identified while underlining the improvements and innovations necessary for clinical use.

Pharmacological Adjuncts to Vitrectomy Surgery

Pharmacological adjuncts to vitrectomy surgery are useful tools to better deal with surgery. Their introduction has enriched the therapeutic choice before, during and after operations. Although several classifications could be made to frame adjuncts to vitrectomy, we preferred to divide the pharmacological adjuncts to vitrectomy surgery for therapeutic use in the pre-operatory procedure (neo-adjuvant), for intraoperative use and for post-operatory practice (adjuvant). This type of classification allowed us to explore all the adjuncts based on the timing of their use. The actual interest in vitrectomy surgery is giving rise to considerable interest in new molecules with and without the pharmacological effect that will soon be available for the aid of vitreoretinal surgery.

Robot-assisted tremor control for performance enhancement of retinal microsurgeons

Pars plana vitrectomy is a challenging, minimally invasive microsurgical procedure due to its intrinsic manoeuvres and physiological limits that constrain human capability. An important human limitation is physiological hand tremor, which can significantly increase the risk of iatrogenic retinal damage resulting from unintentional manoeuvres that affect anatomical and functional surgical outcomes. The limitations imposed by normal physiological tremor are more evident and challenging during ‘micron-scale’ manoeuvres such as epiretinal membrane and internal limiting membrane peeling, and delicate procedures requiring coordinated bimanual surgery such as tractional retinal detachment repair. Therefore, over the previous three decades, attention has turned to robot-assisted surgical devices to overcome these challenges. Several systems have been developed to improve microsurgical accuracy by cancelling hand tremor and facilitating faster, safer and more effective microsurgeries. By markedly reducing tremor, microsurgical precision is improved to a level beyond present human capabilities. In conclusion, robotics offers potential advantages over free-hand microsurgery as it is currently performed during ophthalmic surgery and opens the door to a new class of revolutionary microsurgical modalities. The skills transfer that is beyond human capabilities to robotic technology is a logical next step in microsurgical evolution.

The Blunt End: Surgical Challenges of Gene Therapy for Inherited Retinal Diseases

PURPOSE

To review barriers to effective transduction of cells in the subretinal plane during gene therapy surgery for inherited retinal dystrophies (IRD).

DESIGN

Perspective.

METHODS

Case-based learning in clinical trials and commercial applications of gene therapy in a tertiary care, university-affiliated hospital. MEDLINE search for publications relevant to retinal surgical technique for gene therapy, clinical trials results for gene therapy of IRD, adenoviral-associated viral vector design, and immune response to viral vectors.

RESULTS

The most important surgical issues are safe access to the subretinal space, intraoperative visualization with optical coherence tomography to protect the macula, and quantitation of viral dose. Other issues for retinal surgeons are patient selection, target zone planning, and control of inflammation. Vector-related issues that may affect the precision of treatment involve capsid interaction with the innate and adaptive immune systems and selective targeting of cell types.

CONCLUSIONS

Most current gene therapy vectors for monogenic IRD require physical proximity to target tissues under the retina in order to work. New surgical skills and new instrumentation are under development. So far, the host immune response does not seem to cause rejection of genes delivered by viral vectors but the efficiency of transduction can only be indirectly assessed by long-term visual outcomes.