Robotic Colonoscopy and Beyond: Insights into Modern Lower Gastrointestinal Endoscopy

Lower gastrointestinal endoscopy is considered the gold standard for the diagnosis and removal of colonic polyps. Delays in colonoscopy following a positive fecal immunochemical test increase the likelihood of advanced adenomas and colorectal cancer (CRC) occurrence. However, patients may refuse to undergo conventional colonoscopy (CC) due to fear of possible risks and pain or discomfort. In this regard, patients undergoing CC frequently require sedation to better tolerate the procedure, increasing the risk of deep sedation or other complications related to sedation. Accordingly, the use of CC as a first-line screening strategy for CRC is hampered by patients' reluctance due to its invasiveness and anxiety about possible discomfort. To overcome the limitations of CC and improve patients' compliance, several studies have investigated the use of robotic colonoscopy (RC) both in experimental models and in vivo. Self-propelling robotic colonoscopes have proven to be promising thanks to their peculiar dexterity and adaptability to the shape of the lower gastrointestinal tract, allowing a virtually painless examination of the colon. In some instances, when alternatives to CC and RC are required, barium enema (BE), computed tomographic colonography (CTC), and colon capsule endoscopy (CCE) may be options. However, BE and CTC are limited by the need for subsequent investigations whenever suspicious lesions are found. In this narrative review, we discussed the current clinical applications of RC, CTC, and CCE, as well as the advantages and disadvantages of different endoscopic procedures, with a particular focus on RC.

Anchoring Mechanism for Capsule Endoscope: Mechanical Design, Fabrication and Experimental Evaluation

Capsule endoscopes are widely used to diagnose gut-related problems, but they are passive in nature and cannot actively move inside the gut. This paper details the design process and development of an anchoring mechanism and actuation system to hold a capsule in place within the small intestine. The design centres around the mechanical structure of the anchor that makes use of compliant Sarrus linkage legs, which extend to make contact with the intestine, holding the capsule in place. Three variants with 2 legs, 3 legs and 4 legs of the anchoring mechanism were tested using a shape memory alloy spring actuator (5 mm × ϕ 3.4 mm). The experiments determine that all the variants can anchor at the target site and resist peristaltic forces of 346 mN. The proposed design is well suited for an intestine with a diameter of 19 mm. The proposed design allows the capsule endoscopes to anchor at the target site for a better and more thorough examination of the targeted region. The proposed anchoring mechanism has the potential to become a vital apparatus for clinicians to use with capsule endoscopes in the future.

Electromagnetic tool for the endoscopic creation of colon anastomoses-development and feasibility assessment of a novel anastomosis compression implant approach

BACKGROUND

Colorectal anastomoses are among the most commonly performed interventions in abdominal surgery, while associated patient trauma is still high. Most recent trends of endoscopic anastomosis devices integrate magnetic components to overcome the challenges of minimally invasive surgery. However, the mutual attraction between magnetic implant halves may increase the risk of inadvertently pinching healthy structures. Thus, we present a novel anastomosis device to improve system controllability and flexibility.

METHODS

A magnetic implant and an applicator with electromagnetic control units were developed. The interaction of magnetic implants with the electromagnets bears particular challenges with respect to the force-related dimensioning. Here, attraction forces must be overcome by the electromagnet actuation to detach the implant, while the attraction force between the implant halves must be sufficient to ensure a stable connection. Thus, respective forces were measured and the detachment process was reproducibly investigated. Patient hazards, associated with resistance-related heating of the coils were investigated.

RESULTS

Anastomosis formation was reproducibly successful for an implant, with an attraction force of 1.53 [Formula: see text], resulting in a compression pressure of [Formula: see text]. The implant was reproducibly detachable from the applicator at the anastomosis site. Coils heated up to a maximum temperature of [Formula: see text]. Furthermore, we were able to establish a neat reconnection of intestinal bowel endings using our implant.

DISCUSSION

As we achieved nearly equal compression forces with our implant as other magnetic anastomosis systems did (Magnamosis™: 1.48 N), we concluded that our approach provides sufficient holding strength to counteract the forces acting immediately postoperatively, which would eventually lead to an undesired slipping of the implant halves during the healing phase. Based on heat transfer investigations, preventive design specifications were derived, revealing that the wall thickness of a polymeric isolation is determined rather by stability considerations, than by heat shielding requirements.

Analysis and Comparison of Electromagnetic Microrobotic Platforms for Biomedical Applications

Magnetic microrobotics is a promising technology for improving minimally invasive surgery (MIS) with the ambition of enhancing patient care and comfort. The potential benefits include limited incisions, less hemorrhaging and postoperative pain, and faster recovery time. To achieve this, a key issue relies on the design of a proper electromagnetic actuation (EMA) setup which is based on the use of magnetic sources. The magnetic field and its gradient generated by the EMA platform is then used to induce magnetic torque and force for microrobot manipulations inside the human body. Like any control systems, the EMA system must be adapted to the given controlled microrobot and customized for the application. With great research efforts on magnetic manipulating of microrobots, the EMA systems are approaching commercial applications, and their configurations are becoming more suitable to be employed in real medical surgeries. However, most of the proposed designs have not followed any specific rule allowing to take into account the biomedical applications constraints. Through reviewing the different proposed EMA systems in the literature, their various specifications and configurations are comprehensively discussed and analyzed. This study focus on EMA platforms that use electromagnets. From this review and based on the biomedical application specifications, the appropriate EMA system can be determined efficiently.

Next-generation ingestible devices: sensing, locomotion and navigation

There is significant interest in exploring the human body's internal activities and measuring important parameters to understand, treat and diagnose the digestive system environment and related diseases. Wireless capsule endoscopy (WCE) is widely used for gastrointestinal (GI) tract exploration due to its effectiveness as it provides no pain and is totally tolerated by the patient. Current ingestible sensing technology provides a valuable diagnostic tool to establish a platform for monitoring the physiological and biological activities inside the human body. It is also used for visualizing the GI tract to observe abnormalities by recording the internal cavity while moving. However, the capsule endoscopy is still passive, and there is no successful locomotion method to control its mobility through the whole GI tract. Drug delivery, localization of abnormalities, cost reduction and time consumption are improvements that can be gained from having active ingestible WCEs. In this article, the current technological developments of ingestible devices including sensing, locomotion and navigation are discussed and compared. The main features required to implement next-generation active WCEs are explored. The methods are evaluated in terms of the most important features such as safety, velocity, complexity of design, control, and power consumption.

Guidelines for Robotic Flexible Endoscopy at the Time of COVID-19

Flexible endoscopy involves the insertion of a long narrow flexible tube into the body for diagnostic and therapeutic procedures. In the gastrointestinal (GI) tract, flexible endoscopy plays a major role in cancer screening, surveillance, and treatment programs. As a result of gas insufflation during the procedure, both upper and lower GI endoscopy procedures have been classified as aerosol generating by the guidelines issued by the respective societies during the COVID-19 pandemic-although no quantifiable data on aerosol generation currently exists. Due to the risk of COVID-19 transmission to healthcare workers, most societies halted non-emergency and diagnostic procedures during the lockdown. The long-term implications of stoppage in cancer diagnoses and treatment is predicted to lead to a large increase in preventable deaths. Robotics may play a major role in this field by allowing healthcare operators to control the flexible endoscope from a safe distance and pave a path for protecting healthcare workers through minimizing the risk of virus transmission without reducing diagnostic and therapeutic capacities. This review focuses on the needs and challenges associated with the design of robotic flexible endoscopes for use during a pandemic. The authors propose that a few minor changes to existing platforms or considerations for platforms in development could lead to significant benefits for use during infection control scenarios.

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.

Frontiers of Robotic Colonoscopy: A Comprehensive Review of Robotic Colonoscopes and Technologies

Flexible colonoscopy remains the prime mean of screening for colorectal cancer (CRC) and the gold standard of all population-based screening pathways around the world. Almost 60% of CRC deaths could be prevented with screening. However, colonoscopy attendance rates are affected by discomfort, fear of pain and embarrassment or loss of control during the procedure. Moreover, the emergence and global thread of new communicable diseases might seriously affect the functioning of contemporary centres performing gastrointestinal endoscopy. Innovative solutions are needed: artificial intelligence (AI) and physical robotics will drastically contribute for the future of the healthcare services. The translation of robotic technologies from traditional surgery to minimally invasive endoscopic interventions is an emerging field, mainly challenged by the tough requirements for miniaturization. Pioneering approaches for robotic colonoscopy have been reported in the nineties, with the appearance of inchworm-like devices. Since then, robotic colonoscopes with assistive functionalities have become commercially available. Research prototypes promise enhanced accessibility and flexibility for future therapeutic interventions, even via autonomous or robotic-assisted agents, such as robotic capsules. Furthermore, the pairing of such endoscopic systems with AI-enabled image analysis and recognition methods promises enhanced diagnostic yield. By assembling a multidisciplinary team of engineers and endoscopists, the paper aims to provide a contemporary and highly-pictorial critical review for robotic colonoscopes, hence providing clinicians and researchers with a glimpse of the major changes and challenges that lie ahead.

In Situ Generated Medical Devices

Medical devices play a major role in all areas of modern medicine, largely contributing to the success of clinical procedures and to the health of patients worldwide. They span from simple commodity products such as gauzes and catheters, to highly advanced implants, e.g., heart valves and vascular grafts. In situ generated devices are an important family of devices that are formed at their site of clinical function that have distinct advantages. Among them, since they are formed within the body, they only require minimally invasive procedures, avoiding the pain and risks associated with open surgery. These devices also display enhanced conformability to local tissues and can reach sites that otherwise are inaccessible. This review aims at shedding light on the unique features of in situ generated devices and to underscore leading trends in the field, as they are reflected by key developments recently in the field over the last several years. Since the uniqueness of these devices stems from their in situ generation, the way they are formed is crucial. It is because of this fact that in this review, the medical devices are classified depending on whether their in situ generation entails chemical or physical phenomena.

An Innovative Wireless Endoscopic Capsule With Spherical Shape

This paper aims to contribute to the advancement of the Wireless Capsule Endoscopy (WCE) field for ColoRectal Cancer (CRC) screening, by developing all electronic circuits to build an innovative wireless endoscopic capsule with a spherical shape, conceived to reduce the friction during its locomotion and thus improving patient's acceptability. The proposed capsule embeds an image sensor with optics and Light Emitting Diodes (LEDs), a control unit with a telemetry module, an actuation system, a battery with a smart recharging circuit able to recharge in 20 minutes, a smart power-on circuit and a localization module. Everything is devised to fit in a small spherical shape with a diameter of 26 mm and a weight of 12.70 g. The authors present a description of the sub-modules involved in the capsule development, together with the firmware and hardware integration. In order to reduce the bandwidth for matching the specifications of the target commercial telemetry, the firmware interfacing of a custom encoder was performed, which is able to compress the incoming images with a negligible loss of information and occupying a number of Look Up-Tables (LUTs) less than 1780. As a preliminary work, a versatile Field Programmable Gate Arrays (FPGA) based demo-board system has been developed in order to test and optimize the functionalities and the performance of the single sub-modules and wireless vision chain system. This work allows to demonstrate the feasibility of a complex biomedical system, with severe constraints by highlighting the necessity to enhance the frame rate in the future.

Frontiers of robotic endoscopic capsules: a review

Digestive diseases are a major burden for society and healthcare systems, and with an aging population, the importance of their effective management will become critical. Healthcare systems worldwide already struggle to insure quality and affordability of healthcare delivery and this will be a significant challenge in the midterm future. Wireless capsule endoscopy (WCE), introduced in 2000 by Given Imaging Ltd., is an example of disruptive technology and represents an attractive alternative to traditional diagnostic techniques. WCE overcomes conventional endoscopy enabling inspection of the digestive system without discomfort or the need for sedation. Thus, it has the advantage of encouraging patients to undergo gastrointestinal (GI) tract examinations and of facilitating mass screening programmes. With the integration of further capabilities based on microrobotics, e.g. active locomotion and embedded therapeutic modules, WCE could become the key-technology for GI diagnosis and treatment. This review presents a research update on WCE and describes the state-of-the-art of current endoscopic devices with a focus on research-oriented robotic capsule endoscopes enabled by microsystem technologies. The article also presents a visionary perspective on WCE potential for screening, diagnostic and therapeutic endoscopic procedures.

Magnetically driven medical devices: a review

A widely accepted definition of a medical device is an instrument or apparatus that is used to diagnose, prevent or treat disease. Medical devices take a broad range of forms and utilize various methods to operate, such as physical, mechanical or thermal. Of particular interest in this paper are the medical devices that utilize magnetic field sources to operate. The exploitation of magnetic fields to operate or drive medical devices has become increasingly popular due to interesting characteristics of magnetic fields that are not offered by other phenomena, such as mechanical contact, hydrodynamics and thermodynamics. Today, there is a wide range of magnetically driven medical devices purposed for different anatomical regions of the body. A review of these devices is presented and organized into two groups: permanent magnetically driven devices and electromagnetically driven devices. Within each category, the discussion will be further segregated into anatomical regions (e.g., gastrointestinal, ocular, abdominal, thoracic, etc.).