A novel self-propelled disposable colonoscope is effective for colonoscopy in humans (with video)

MorphGI: A Self-Propelling Soft Robotic Endoscope Through Morphing Shape

Colonoscopy is currently the best method for detecting bowel cancer, but fundamental design and construction have not changed significantly in decades. Conventional colonoscope (CC) is difficult to maneuver and can lead to pain with a risk of damaging the bowel due to its rigidity. We present the MorphGI, a robotic endoscope system that is self-propelling and made of soft material, thus easy to operate and inherently safe to patient. After verifying kinematic control of the distal bending segment, the system was evaluated in: a benchtop colon simulator, using multiple colon configurations; a colon simulator with force sensors; and surgically removed pig colon tissue. In the colon simulator, the MorphGI completed a colonoscopy in an average of 10.84 min. The MorphGI showed an average of 77% and 62% reduction in peak forces compared to a CC in high- and low-stiffness modes, respectively. Self-propulsion was demonstrated in the excised tissue test but not in the live pig test, due to anatomical differences between pig and human colons. This work demonstrates the core features of MorphGI.

Evaluation of a novel disposable esophagogastroduodenoscopy system in emergency, bedside, and intraoperative settings: Pilot study (with videos)

OBJECTIVES

The disposable esophagogastroduodenoscopy (EGD) system is a novel endoscopic device which is highly portable and is designed to eliminate the risk of cross-infection caused by reusable EGD. This study aimed to investigate the feasibility and safety of disposable EGD in emergency, bedside, and intraoperative settings.

METHODS

This was a prospective, single-center, noncomparative study. Disposable EGD was used for emergency, bedside, and intraoperative endoscopies in 30 patients. The primary end-point was the technical success rate of the disposable EGD. Secondary end-points included technical performance indicators including clinical operability, image quality score, procedure time, the incidence of device malfunction and/or failure, and the incidence of adverse events.

RESULTS

A total of 30 patients underwent diagnosis and/or treatment with disposable EGD. Therapeutic EGD was performed on 13/30 patients, including hemostasis (n = 3), foreign body retrieval (n = 6), nasoenteric tube placement (n = 3), and percutaneous endoscopic gastrostomy (n = 1). The technical success rate was 100%: all procedures and indicated interventions were completed without changing to a conventional upper endoscope. The mean image quality score obtained immediately after procedure completion was 3.72 ± 0.56. The mean (± SD) procedure time was 7.4 (± 7.6) min. There were no device malfunctions or failures, device-related adverse events, or overall adverse events.

CONCLUSION

The disposable EGD may be a feasible alternative to the traditional EGD in emergency, bedside, and intraoperative settings. Preliminary data show that it is a safe and effective tool for diagnosis and treatment in emergency and bedside upper gastrointestinal cases.

TRIAL REGISTRATION

Chinese Clinical Trial Registry (Trial ID: ChiCTR2100051452, https://www.chictr.org.cn/showprojen.aspx?proj=134284).

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.

Robotic, self-propelled, self-steerable, and disposable colonoscopes: Reality or pipe dream? A state of the art review

Robotic colonoscopes could potentially provide a comfortable, less painful and safer alternative to standard colonoscopy. Recent exciting developments in this field are pushing the boundaries to what is possible in the future. This article provides a comprehensive review of the current work in robotic colonoscopes including self-propelled, steerable and disposable endoscopes that could be alternatives to standard colonoscopy. We discuss the advantages and disadvantages of these systems currently in development and highlight the technical readiness of each system to help the reader understand where and when such systems may be available for routine clinical use and get an idea of where and in which situation they can best be deployed.

Application of robotic technologies in lower gastrointestinal tract endoscopy: A systematic review

BACKGROUND

Conventional optical colonoscopy is considered the gold standard investigation for colorectal tract pathology including colorectal malignancy, polyps and inflammatory bowel disease. Inherent limitations exist with current generation endoscopic technologies, including, but not limited to, patient discomfort, endoscopist fatigue, narrow field of view and missed pathology behind colonic folds. Rapid developments in medical robotics have led to the emergence of a variety of next-generation robotically-augmented technologies that could overcome these limitations.

AIM

To provide a comprehensive summary of recent developments in the application of robotics in lower gastrointestinal tract endoscopy.

METHODS

A systematic review of the literature was performed from January 1, 2000 to the January 7, 2021 using EMBASE, MEDLINE and Cochrane databases. Studies reporting data on the use of robotic technology in ex vivo or in vivo animal and human experiments were included. In vitro studies (studies using synthetic colon models), studies evaluating non-robotic technology, robotic technology aimed at the upper gastrointestinal tract or paediatric endoscopy were excluded. System ergonomics, safety, visualisation, and diagnostic/therapeutic capabilities were assessed.

RESULTS

Initial literature searching identified 814 potentially eligible studies, from which 37 were deemed suitable for inclusion. Included studies were classified according to the actuation modality of the robotic device(s) as electromechanical (EM) (n = 13), pneumatic (n = 11), hydraulic (n = 1), magnetic (n = 10) and hybrid (n = 2) mechanisms. Five devices have been approved by the Food and Drug Administration, however most of the technologies reviewed remain in the early phases of testing and development. Level 1 evidence is lacking at present, but early reports suggest that these technologies may be associated with improved pain and safety. The reviewed devices appear to be ergonomically capable and efficient though to date no reports have convincingly shown diagnostic or therapeutic superiority over conventional colonoscopy.

CONCLUSION

Significant progress in robotic colonoscopy has been made over the last couple of decades. Improvements in design together with the integration of semi-autonomous and autonomous systems over the next decade will potentially result in robotic colonoscopy becoming more commonplace.

Endorobots for Colonoscopy: Design Challenges and Available Technologies

Colorectal cancer (CRC) is the second most common cause of cancer death worldwide, after lung cancer (Sung et al., 2021). Early stage detection is key to increase the survival rate. Colonoscopy remains to be the gold standard procedure due to its dual capability to optically inspect the entire colonic mucosa and to perform interventional procedures at the same time. However, this causes pain and discomfort, whereby it requires sedation or anaesthesia of the patient. It is a difficult procedure to perform that can cause damage to the colonic wall in some cases. Development of new technologies aims to overcome the current limitations on colonoscopy by using advancements in endorobotics research. The design of these advanced medical devices is challenging because of the limited space of the lumen, the contorted shape, and the long tract of the large bowel. The force applied to the colonic wall needs to be controlled to avoid collateral effects such as injuries to the colonic mucosa and pain during the procedure. This article discusses the current challenges in the colonoscopy procedure, the available locomotion technologies for endorobots used in colonoscopy at a prototype level and the commercial products available.

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.

Hydro-jet propelled colonoscopy: proof of concept in a phantom colon

BACKGROUND

Colonoscopy is a widely used and effective procedure, but it often causes patient discomfort and its execution requires considerable skill and training. We demonstrate an alternative approach to colonoscope propulsion with the potential to minimise patient discomfort by reducing the forces exerted on the colonic wall and mesentery, and to reduce the level of skill required for execution.

METHODS

A prototype colonoscopic device is described, consisting of a tethered capsule that is propelled and manoeuvred through a water-filled colon (hydro-colonoscopy) by an array of water jets. As an initial proof of concept, experiments were performed to assess the ability of the device to navigate through a simplified PVA cryogel human colon phantom arranged in various anatomical configurations.

RESULTS

The prototype was capable of successfully navigating through three out of four colon configurations: a simple layout, alpha loop and reverse alpha loop. It was unable to negotiate the fourth configuration involving an "N loop", but this was attributed to problems with the colon phantom. In the successful test replicates, mean complete insertion (i.e. caecal intubation) time was 4.7 min. Measured pressures, temperatures and forces exerted on the colon appeared to be within a physiologically acceptable range. The results demonstrate the viability of propelling a colonoscope through a colon phantom using hydro-jets.

CONCLUSIONS

Results indicate that this approach has the potential to enable rapid and safe caecal intubation. This suggests that further development towards clinical translation is worthwhile.

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.

Robotics in flexible endoscopy: current status and future prospects

PURPOSE OF REVIEW

Advanced endoscopy procedures are technically challenging and require extensive training. Recent technological advances made in computer science and robotics have the potential to enhance the performance of complex intraluminal and transluminal interventions and potentially optimize precision and safety. This review covers the different technologies used for robot-assisted interventions in the gastrointestinal tract, organized according to their clinical availability, and focusing on flexible endoscopy-based systems.

RECENT FINDINGS

In the curvilinear gastrointestinal anatomy, robotic technology can enhance flexible endoscopes to augment effectiveness, safety, and therapeutic capabilities, particularly for complex intraluminal and transluminal interventions. Increased visual angles, increased degrees of freedom of instrumentation, optimized navigation, and locomotion, which may lead to a reduced physician learning curve and workload, are promising achievements with the promise to ultimately replace conventional endoscopy techniques for screening and therapeutic endoscopy.

SUMMARY

The majority of these devices are not commercially available yet. The best clinical applications are also currently being researched. Nonetheless, robotic assistance may encourage surgeons to use flexible endoscopes to administer surgical therapies and increase interest among gastroenterologists in advanced therapies. Robotics may be a means to overcome the technical obstacles of incisionless natural orifice procedures and favor an increased adoption of complex endoscopic procedures such as third-space therapies.

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.

The future of endoscopy: Advances in endoscopic image innovations

The latest state of the art technological innovations have led to a palpable progression in endoscopic imaging and may facilitate standardisation of practice. One of the most rapidly evolving modalities is artificial intelligence with recent studies providing real-time diagnoses and encouraging results in the first randomised trials to conventional endoscopic imaging. Advances in functional hypoxia imaging offer novel opportunities to be used to detect neoplasia and the assessment of colitis. Three-dimensional volumetric imaging provides spatial information and has shown promise in the increased detection of small polyps. Studies to date of self-propelling colonoscopes demonstrate an increased caecal intubation rate and possibly offer patients a more comfortable procedure. Further development in robotic technology has introduced ex vivo automated locomotor upper gastrointestinal and small bowel capsule devices. Eye-tracking has the potential to revolutionise endoscopic training through the identification of differences in experts and non-expert endoscopist as trainable parameters. In this review, we discuss the latest innovations of all these technologies and provide perspective into the exciting future of diagnostic luminal endoscopy.

Robotic colonoscopy: efficacy, tolerability and safety. Preliminary clinical results from a pilot study

BACKGROUND

Robotic colonoscopy (RC) is a pneumatically-driven self-propelling platform (Endotics System®) able to investigate the colon, in order to reduce pain and discomfort.

AIMS

(1) to describe the progress in gaining experience and skills of a trainee in RC; (2) to show the clinical outcomes of RC.

METHODS

Pilot study. An experienced endoscopist started a training on RC whose progress was assessed comparing the results of 2 consecutive blocks of 27 (Group A) and 28 (Group B) procedures. CIR (Cecal Intubation Rate), CIT (Cecal Intubation Time) and Withdrawal Time (WT) were measured. Polyp Detection Rate (PDR), Adenoma Detection Rate (ADR) and Advanced Neoplasia Detection Rate (ANDR) were calculated. Possible adverse events were recorded. At the end of the procedure all patients completed a visual analog scale (VAS) to measure their perceived pain during RC and reported their willingness to repeat RC.

RESULTS

General CIR was 92.7%, reaching 100% in Group B. Comparing the two groups, CIT significantly decreased from 55 to 22 min (p value 0.0007), whereas procedures with CIT ≤ 20 min increased (p value 0.037). WT significatively reduced from 21 to 16 min (p value 0.0186). PDR was 40% (males 62.5%, females 14.3%). ADR was 26.7% (males 27.5%, females 14.3%). Most of patients judged the procedure as mild or no distress, with high willingness-to-repeat the RC (92.7%).

CONCLUSIONS

Our results about RC are encouraging as preliminary experience, with clear individual learning progress, accurate diagnosis in a painless or comfortable procedure and with possibility to remove polypoid lesions. Studies with larger populations are needed to confirm obtained results.

The evolution of lower gastrointestinal endoscopy: where are we now?

Lower gastrointestinal endoscopy has evolved over time, fulfilling a widening diagnostic and therapeutic remit. As our understanding of colorectal cancer and its prevention has improved, endoscopy has progressed with improved diagnostic technologies and advancing endoscopic therapies. Despite this, the fundamental design of the endoscope has remained similar since its inception. This review presents the important role lower gastrointestinal endoscopy serves in the prevention of colorectal cancer and the desirable characteristics of the endoscope that would enhance this. A brief history of the endoscope is presented. Current and future robotic endoscopic platforms, which may fulfil these desirable characteristics, are discussed. The incorporation of new technologies from allied scientific disciplines will help the endoscope fulfil its maximum potential in preventing the increasing global burden of colorectal cancer. There are a number of endoscopic platforms under development, which show significant promise.

Advanced endoscopy technologies to improve the detection and characterisation of colorrectal polyps

Colorectal cancer is a major health problem. An improvement to its survival has been demonstrated by performing colonoscopy screenings and removing its precursor lesions: polyps. However, colonoscopy is not infallible and multiple strategies have been proposed aimed at improving the quality thereof. This report describes the endoscopic systems available to improve the detection and characterization of polyps, the different classifications for histological prediction and the current indications of advanced endoscopic diagnostic techniques.

Emerging next-generation robotic colonoscopy systems towards painless colonoscopy

Advances in the field of robotics have allowed modern technology to be integrated into medicine and that can minimize patients suffering from the side effects that are inherent to procedures for improving their quality of life. Conventional devices that are used for colonoscopies are rigid and require a high level of expertise from endoscopists to perform the procedure. Advances in robot-assisted colonoscopic systems now produce softer, more slender, automated designs that no longer require the operator to use forceful pushing to advance the colonoscope inside the colon, reducing risks to the patient of perforation and pain. It is challenging to reprocess these scopes for reuse as the materials used can be damaged during decontamination, leading to the possible risks of cross-infection by pathogenic microorganisms when reused by patients. An ideal solution is to eliminate these contamination risks to patients by adopting sterile, single-use scopes straight from the manufacturer's package to the patient. With this idea in mind, emerging developments that push the boundaries in this area will benefit patients and encourage the public to participate in and adhere better to colonoscopy screening to reduce the development of colorectal cancer. Thus, in light of these concerns and challenges, to encourage patients undergoing colorectal screening to comply with colonoscopy procedures that they are less invasive, changes in the design and materials are necessary. One of the more promising technological advances in this area is the advent of robotic colonoscopy.

Endoscopy robotics: Current and future applications

Many different types of endoscopy robot have been developed or are under development. Some of these innovative biotechnologies are dedicated to complex endoscopic procedures such as endoscopic submucosal dissection whereas others are purely diagnostic. In endoscopy robotics, there are still several problems that need a solution. These problems basically concern robotic locomotion and instrument control, as well as clinical application. In most cases, the technology is still under development. The current fields of investigation are augmented reality, advances in actuation and reduction of hysteresis, optical analysis, wireless movement transmission and many others. Besides endoscopic submucosal dissection, other promising fields of implementation of endoscopy robots are natural orifices transluminal endoscopic surgery and bariatric endoscopy. Obviously, endoscopy robots are expensive, but both doctors and health system providers are becoming more aware of the possibilities that these platforms can offer. Improvement of the performance of endoscopy robots undoubtedly will lead to their widespread use and, therefore, a balance in cost-effectiveness.

Rates of infection after colonoscopy and osophagogastroduodenoscopy in ambulatory surgery centres in the USA

OBJECTIVE

Over 15 million colonoscopies and 7 million osophagogastroduodenoscopies (OGDs) are performed annually in the USA. We aimed to estimate the rates of infections after colonoscopy and OGD performed in ambulatory surgery centres (ASCs).

DESIGN

We identified colonoscopy and OGD procedures performed at ASCs in 2014 all-payer claims data from six states in the USA. Screening mammography, prostate cancer screening, bronchoscopy and cystoscopy procedures were comparators. We tracked infection-related emergency department visits and unplanned in-patient admissions within 7 and 30 days after the procedures, examined infection sites and organisms and analysed predictors of infections. We investigated case-mix adjusted variation in infection rates by ASC.

RESULTS

The rates of postendoscopic infection per 1000 procedures within 7 days were 1.1 for screening colonoscopy, 1.6 for non-screening colonoscopy and 3.0 for OGD; all higher than screening mammography (0.6) but lower than bronchoscopy (15.6) and cystoscopy (4.4) (p<0.0001). Predictors of postendoscopic infection included recent history of hospitalisation or endoscopic procedure; concurrence with another endoscopic procedure; low procedure volume or non-freestanding ASC; younger or older age; black or Native American race and male sex. Rates of 7-day postendoscopic infections varied widely by ASC, ranging from 0 to 115 per 1000 procedures for screening colonoscopy, 0 to 132 for non-screening colonoscopy and 0 to 62 for OGD.

CONCLUSION

We found that postendoscopic infections are more common than previously thought and vary widely by facility. Although screening colonoscopy is not without risk, the risk is lower than diagnostic endoscopic procedures.

Robotics for Advanced Therapeutic Colonoscopy

Although colonoscopy was originally a diagnostic imaging procedure, it has now expanded to include an increasing range of therapeutic interventions. These procedures require precise maneuvers of instruments, execution of force, efficient transmission of force from the operator to the point of application, and sufficient dexterity in the mobilization of endoscopic surgical instruments. The conventional endoscope is not designed to support technically demanding endoscopic procedures. In case of colonoscopy, the tortuous anatomy of the colon makes inserting, moving, and orientating the endoscope difficult. Exerting excessive pressure can cause looping of the endoscope, pain to the patient, and even perforation of the colon. To mitigate the technical constraints, numerous technically enhanced systems have been developed to enable better control of instruments and precise delivery of force in the execution of surgical tasks such as apposing, grasping, traction, counter-traction, and cutting of tissues. Among the recent developments are highly dexterous robotic master and slave systems, computer-assisted or robotically enhanced conventional endoscopes, and autonomously driven locomotion devices that can effortlessly traverse the colon. Developments in endoscopic instrumentations have overcome technical barriers and opened new horizons for further advancements in therapeutic interventions. This review describes examples of some of these systems in the context of their applications to advanced therapeutic colonoscopy.

New endoscopes and add-on devices to improve colonoscopy performance

Colonoscopy is the gold standard for colorectal cancer prevention; however, it is still an imperfect modality. Precancerous lesions can be lost during screening examinations, thus increasing the risk of interval cancer. A variety of factors either patient-, or endoscopist dependent or even the procedure itself may contribute to loss of lesions. Sophisticated modalities including advanced technology endoscopes and add-on devices have been developed in an effort to eliminate colonoscopy's drawbacks and maximize its ability to detect potentially culprit polyps. Novel colonoscopes aim to widen the field of view. They incorporate more than one cameras enabling simultaneous image transmission. In that way the field of view can expand up to 330°. On the other hand a plethora of add-on devices attachable on the standard colonoscope promise to detect lesions in the proximal aspect of colonic folds either by offering a retrograde view of the lumen or by straightening the haustral folds during withdrawal. In this minireview we discuss how these recent advances affect colonoscopy performance by improving its quality indicators (cecal intubation rate, adenoma detection rate) and other metrics (polyp detection rate, adenomas per colonoscopy, polyp/adenoma miss rate) associated with examination's outcomes.

Flexible Gastro-intestinal Endoscopy - Clinical Challenges and Technical Achievements

Flexible gastro-intestinal (GI) endoscopy is an integral diagnostic and therapeutic tool in clinical gastroenterology. High quality standards for safety, patients' comfort, and efficiency have already been achieved. Clinical challenges and technical approaches are discussed in this short review.

Image enhanced endoscopy for further characterization of mucosal and vascular patterns includes dye-spray or virtual chromoendoscopy. For confocal laser endoscopy, endocytoscopy, and autofluorescence clinical value has not yet been finally evaluated. An extended viewing field provided by additional cameras in new endoscopes can augment detection of polyps behind folds. Attachable caps, flaps, or balloons can be used to flatten colonic folds for better visualization and stable position.

Variable stiffness endoscopes, radiation-free visualization of endoscope position, and different overtube devices help reducing painful loop formation in clinical routine. Computer assisted and super flexible self-propelled colonoscopes for painless sedation-free endoscopy need further research. Single-use devices might minimize the risk of infection transmission in the future.

Various exchangeable accessories are available for resection, dissection, tunneling, hemostasis, treatment of stenosis and closure of defects, including dedicated suturing devices. Multiple arm flexible devices controlled via robotic platforms for complex intraluminal and transmural endoscopic procedures require further improvement.