Magnetic-assisted capsule endoscopy in the upper GI tract by using a novel navigation system (with video)

Optimal Motion Control of a Capsule Endoscope in the Stomach Utilizing a Magnetic Navigation System with Dual Permanent Magnets

We propose a method to control the motion of a capsule endoscope (CE) in the stomach utilizing either a single external permanent magnet (EPM) or dual EPMs to extend the examination of the upper gastrointestinal tract. When utilizing the conventional magnetic navigational system (MNS) with a single EPM to generate tilting and rotational motions of the CE, undesired translational motion of the CE may prevent accurate examination. We analyzed the motion of the CE by calculating the magnetic torque and magnetic force applied to the CE using the point-dipole approximation model. Using the proposed model, we propose a method to determine the optimal position and orientation of the EPM to generate tilting and rotational motions without undesired translational motion of the CE. Furthermore, we optimized the weight of dual EPMs to develop a lightweight MNS. We prototyped the proposed MNS and experimentally verified that the developed MNS can generate tilting and rotational motions of the CE without any translational motion.

Detection of foreign bodies in the canine stomach using capsule endoscopy: a randomized trial

Introduction

This study aimed to assess the effectiveness of capsule endoscopy in detecting gastric foreign bodies in normal dogs, considering variations in the number of foreign bodies and the gastric environment.

Methods

Five healthy male beagles were administered virtual, non-harmful foreign objects that maintained their shape in the stomach. Capsule endoscopy was performed and the images were evaluated by veterinarians and non-veterinarians.

Results

The overall sensitivity and specificity of capsule endoscopy were 99.1 and 90.4%, respectively. Sensitivity and specificity were comparable between veterinarians and non-veterinarians. Sensitivity and specificity in the veterinarian group were 98.7 and 91.2%, respectively, whereas those in the non-veterinarian group were 100 and 88.5%, respectively.

Discussion

Capsule endoscopy is a valuable alternative diagnostic tool for identifying foreign bodies in the stomach, particularly in challenging cases in which conventional imaging or invasive approaches have limitations.

Efficacy and safety of three-dimensional magnetically assisted capsule endoscopy for upper gastrointestinal and small bowel examination

BACKGROUND

Magnetically assisted capsule endoscopy (MACE) showed the feasibility for upper gastrointestinal examination. To further enhance the performance of conventional MACE, it is necessary to provide quality-improved and three-dimensional images. The aim of this clinical study was to determine the efficacy and safety of novel three-dimensional MACE (3D MACE) for upper gastrointestinal and small bowel examination at once.

METHODS

This was a prospective, single-center, non-randomized, and sequential examination study (KCT0007114) at Dongguk University Ilsan Hospital. Adult patients who visited for upper endoscopy were included. The study protocol was conducted in two stages. First, upper gastrointestinal examination was performed using 3D MACE, and a continuous small bowel examination was performed by conventional method of capsule endoscopy. Two hours later, an upper endoscopy was performed for comparison with 3D MACE examination. The primary outcome was confirmation of major gastric structures (esophagogastric junction, cardia/fundus, body, angle, antrum, and pylorus). Secondary outcomes were confirmation of esophagus and duodenal bulb, accuracy for gastric lesions, completion of small bowel examination, 3D image reconstruction of gastric lesion, and safety.

RESULTS

Fifty-five patients were finally enrolled. The examination time of 3D MACE was 14.84 ± 3.02 minutes and upper endoscopy was 5.22 ± 2.39 minutes. The confirmation rate of the six major gastric structures was 98.6% in 3D MACE and 100% in upper endoscopy. Gastric lesions were identified in 43 patients during 3D MACE, and 40 patients during upper endoscopy (Sensitivity 0.97). 3D reconstructed images were acquired for all lesions inspected by 3D MACE. The continuous small bowel examination by 3D MACE was completed in 94.5%. 3D MACE showed better overall satisfaction (3D MACE 9.55 ± 0.79 and upper endoscopy 7.75 ± 2.34, p<0.0001). There were no aspiration or significant adverse event or capsule retention in the 3D MACE examination.

CONCLUSIONS

Novel 3D MACE system is more advanced diagnostic modality than the conventional MACE. And it is possible to perform serial upper gastrointestinal and small bowel examination as a non-invasive and one-step test. It would be also served as a bridge to pan-endoscopy.

A systematic review on diagnosis and treatment of gastrointestinal diseases by magnetically controlled capsule endoscopy and artificial intelligence

Background

Magnetically controlled capsule endoscopy (MCCE) is a non-invasive, painless, comfortable, and safe equipment to diagnose gastrointestinal diseases (GID), partially overcoming the shortcomings of conventional endoscopy and wireless capsule endoscopy (WCE). With advancements in technology, the main technical parameters of MCCE have continuously been improved, and MCCE has become more intelligent.

Objectives

The aim of this systematic review was to summarize the research progress of MCCE and artificial intelligence (AI) in the diagnosis and treatment of GID.

Data Sources and Methods

We conducted a systematic search of PubMed and EMBASE for published studies on GID detection of MCCE, physical factors related to MCCE imaging quality, the application of AI in aiding MCCE, and its additional functions. We synergistically reviewed the included studies, extracted relevant data, and made comparisons.

Results

MCCE was confirmed to have the same performance as conventional gastroscopy and WCE in detecting common GID, while it lacks research in detecting early gastric cancer (EGC). The body position and cleanliness of the gastrointestinal tract are the main factors affecting imaging quality. The applications of AI in screening intestinal diseases have been comprehensive, while in the detection of common gastric diseases such as ulcers, it has been developed. MCCE can perform some additional functions, such as observations of drug behavior in the stomach and drug damage to the gastric mucosa. Furthermore, it can be improved to perform a biopsy.

Conclusion

This comprehensive review showed that the MCCE technology has made great progress, but studies on GID detection and treatment by MCCE are in the primary stage. Further studies are required to confirm the performance of MCCE.

Inadequate gastric preparation and its associated factors for magnetically controlled capsule endoscopy

Goals: To explore factors associated with inadequate gastric preparation for MCE. Background: Factors associated with inadequate gastric preparation for magnetically controlled capsule endoscopy (MCE) remains unclear. Study: Data of patients who underwent MCE from June 2021 to July 2022 were prospectively collected. The gastric cleanliness score (GCS) of the six stomach regions (gastric cardia, fundus, body, angulus, antrum, and pylorus) was recorded. Patients with GCS score ≥18 were defined as the adequate preparation. Factors related to inadequate gastric preparation were analyzed using a logistic regression model with estimated odds ratios (OR). Results: The mean GCS score of 211 patients was 17.01 ± 2.82. In the multivariable analysis, proton pump inhibitor (PPI) use (OR 3.57; 95% CI 1.69-7.95; p < 0.01) and premedication time after administering simethicone <30 min (OR 2.86; 95% CI 1.10-7.39; p = 0.03) were independent risk factors for inadequate gastric preparation. Comparing the gastric cleanliness of different locations, the median GCS of the lower stomach [10.00, IQR (9.50, 11.00)] was significantly higher than that of the upper stomach [7.00, IQR (6.00, 8.00)] (p <0.001). Conclusion: PPI use and inadequate premedication time (<30 min) may reduce the quality of gastric preparation for MCE. The type, dose, duration of medication, and discontinuation time of PPIs was well worth further exploration. Appropriate control of the type and time of premedication may be the key to improving overall gastric cleanliness.

Magnetic-controlled capsule endoscopy performance in aging patients

BACKGROUND

The increasing elderly population and wide use of magnetic capsule endoscopy (MCE) have led to more attention to elderly patients.

AIM

The aim of this study was to assess the performance (including transit time, cleanliness score, positive findings and safety) of MCE in aging patients (≥ 60 years), especially patients over 80 years old.

METHODS

Consecutive patients of ≥ 60 years undergoing MCE at our center from August 2017 to August 2022 were classified into the oldest (≥ 80 years) and the older (60-79 years) groups. Esophageal transit time (ETT), gastric examination time (GET), small bowel transit time (SITT), and the quality of gastric preparation were compared. Information on examination indications, subjective discomforts, adverse events, and MCE outcomes were compared.

RESULTS

Of 293 enrolled patients, 128 patients were in the oldest group and 165 patients were in the older group. ETT and GET were longer in the oldest group, whereas SITT was slightly longer in the oldest patients. Visualization scores were significantly lower in the body and antrum in the oldest patients. The total visualization score was lower in the older group compared with the oldest group; however, the difference was not significant. Cleanliness scores at the fundus and antrum and total cleanliness scores were lower in the oldest patients compared with the older patients. Positive findings and ulcers and erosions in the small intestine were more common in the oldest group. One patient had nausea during the gastric examination. Capsule retention in the cecum occurred in one case.

CONCLUSION

MCE was feasible and safe for aging patients. ETT and GET were markedly longer and gastric cleanliness and visualization were worse, while overall small intestine-positive findings were higher in the oldest patients compared with the older patients.

Clinical guideline on magnetically controlled capsule gastroscopy (2021 edition)

With the development and generalization of endoscopic technology and screening, clinical application of magnetically controlled capsule gastroscopy (MCCG) has been increasing. In recent years, various types of MCCG are used globally. Therefore, establishing relevant guidelines on MCCG is of great significance. The current guidelines containing 23 statements were established based on clinical evidence and expert opinions, mainly focus on aspects including definition and diagnostic accuracy, application population, technical optimization, inspection process, and quality control of MCCG. The level of evidence and strength of recommendations were evaluated. The guidelines are expected to guide the standardized application and scientific innovation of MCCG for the reference of clinicians.

Magnetic controlled capsule endoscope (MCCE)'s diagnostic performance for H. pylori infection status based on the Kyoto classification of gastritis

BACKGROUND

Previous studies have shown that the Kyoto classification of gastritis can accurately predict H. pylori infection status on conventional gastroscopy. The aim of this study was to test whether the Kyoto classification of gastritis applies well to magnetic controlled capsule endoscopy (MCCE).

METHODS

We consecutively recruited 227 participants who underwent both MCCE and urea breath tests (UBTs). Two physicians who were blinded to the UBT results independently made the diagnosis of H. pylori infection status according to 10 findings listed in the Kyoto classification of gastritis after reviewing MCCE images. We also developed 2 predictive models to assess H. pylori infection status by combining these 10 findings.

RESULTS

The MCCE's overall diagnostic accuracy for H. pylori infection status was 80.2%. The sensitivity, specificity and diagnostic odds ratio (DOR) for current infection were 89.4%, 90.1% and 77.1, respectively. Major specific findings were mucosal swelling and spotty redness for current infection, regular arrangement of collecting venules (RAC), streak redness, fundic gland polyp (FGP) for noninfection, and map-like redness for past-infection. In the two prediction models, the area under the curve (AUC) values for predicting noninfection and current infection were 84.7 and 84.9, respectively.

CONCLUSIONS

The Kyoto classification of gastritis applied well to MCCE. H. pylori infection status could be accurately assessed on MCCE according to the Kyoto classification of gastritis.

In vivo animal study of the magnetic navigation system for capsule endoscope manipulation within the esophagus, stomach, and colorectum

BACKGROUND/PURPOSES

Magnetic navigation capsule endoscopy (MNCE) is considered to be an important means to realize the controllable and precise examination of capsule endoscopy (CE) in the unstructured gastrointestinal (GI) tract. For the current magnetic navigation system (MNS), due to the limitation of workspace, driving force, and control method of the CE, only clinical application in the stomach has been realized, whereas the examination of other parts of the GI tract is still in the experimental stage. More preclinical studies are needed to achieve the multisite examination of the GI tract.

METHODS

Based on the MNS (Supiee) developed in the laboratory, an X-ray imaging system with magnetic shielding and a commercial CE are integrated to form the MNCE system. Then, in vivo GI tract experiments with a porcine model are performed to verify the clinical feasibility and safety of this system. Moreover, the effects of different control modes on the efficiency and effect of GI tract examination are studied.

RESULTS

Animal experiments demonstrate that with the MNCE system, it is convenient to achieve steering control in any direction and multiple reciprocating movements of CE in the GI tract. Benefiting from the flexibility of the three basic control modes, the achieved swing movement pattern of CE can effectively reduce the inspection time. It is demonstrated that the esophageal examination time can be reduced from 13.2 to 9.2 min with a maximum movement speed of 5 mm/s.

CONCLUSION

In this paper, the feasibility, safety, and efficacy of the MNCE system for a one-stop examination of the in vivo GI tract (esophagus, stomach, and colorectum) is first demonstrated. In addition, complex movement patterns of CE such as the swinging are proved to effectively improve examination efficiency and disease detection rates. This study is crucial for the clinical application of the MNCE system.

Feasibility and safety of a novel string magnetically controlled capsule endoscopy for esophageal and gastric examination in a porcine model

BACKGROUND

Currently used magnetically controlled capsule gastroscope has many shortcomings, such as low resolution and frame rate, incomplete examination of the esophagus due to rapid passage, and risk of capsule retention. A novel string magnetically controlled capsule endoscopy with high frame rate and resolution can examine the esophagus comprehensively, and has no risk of capsule retention.

AIM

To verify the feasibility and safety of a novel string magnetically controlled capsule endoscopy for esophageal and gastric examination by animal experiments.

METHODS

Magnetically controlled capsule endoscopy (MCE) and traditional gastroscopy were performed on three Bama minipigs successively. The examination time for the esophagus and stomach was recorded. The MCE maneuverability and mucosal visualization in each part of the esophagus and stomach (upper, middle, and lower part of the esophagus, Z-line, and gastric cardia, fundus, body, angulus, antrum, and pylorus). Routine blood and biochemistry parameters of experimental animals before and after examination were analyzed, and adverse reactions occurring during the experiment were recorded.

RESULTS

Compared with traditional gastroscopy, MCE showed no significant difference in esophageal examination time (104.67 s ± 7.02 s vs 88.33 s ± 3.51 s, P = 0.093). The gastric examination time of MCE was longer than that of traditional gastroscopy (25.67 min ± 5.69 min vs 6.00 min ± 1.00 min, P = 0.019). The MCE maneuverability and mucosal visualization were better in the esophagus, Z-line, and gastric body, antrum, and pylorus than in the gastric cardia and fundus. No obvious adverse reactions occurred in experimental animals.

CONCLUSION

The novel string magnetically controlled capsule endoscopy has satisfactory feasibility and safety for esophageal and gastric examination in the porcine model.

Endoscopic capsule robot-based diagnosis, navigation and localization in the gastrointestinal tract

The proliferation of video capsule endoscopy (VCE) would not have been possible without continued technological improvements in imaging and locomotion. Advancements in imaging include both software and hardware improvements but perhaps the greatest software advancement in imaging comes in the form of artificial intelligence (AI). Current research into AI in VCE includes the diagnosis of tumors, gastrointestinal bleeding, Crohn’s disease, and celiac disease. Other advancements have focused on the improvement of both camera technologies and alternative forms of imaging. Comparatively, advancements in locomotion have just started to approach clinical use and include onboard controlled locomotion, which involves miniaturizing a motor to incorporate into the video capsule, and externally controlled locomotion, which involves using an outside power source to maneuver the capsule itself. Advancements in locomotion hold promise to remove one of the major disadvantages of VCE, namely, its inability to obtain targeted diagnoses. Active capsule control could in turn unlock additional diagnostic and therapeutic potential, such as the ability to obtain targeted tissue biopsies or drug delivery. With both advancements in imaging and locomotion has come a corresponding need to be better able to process generated images and localize the capsule’s position within the gastrointestinal tract. Technological advancements in computation performance have led to improvements in image compression and transfer, as well as advancements in sensor detection and alternative methods of capsule localization. Together, these advancements have led to the expansion of VCE across a number of indications, including the evaluation of esophageal and colon pathologies including esophagitis, esophageal varices, Crohn’s disease, and polyps after incomplete colonoscopy. Current research has also suggested a role for VCE in acute gastrointestinal bleeding throughout the gastrointestinal tract, as well as in urgent settings such as the emergency department, and in resource-constrained settings, such as during the COVID-19 pandemic. VCE has solidified its role in the evaluation of small bowel bleeding and earned an important place in the practicing gastroenterologist’s armamentarium. In the next few decades, further improvements in imaging and locomotion promise to open up even more clinical roles for the video capsule as a tool for non-invasive diagnosis of lumenal gastrointestinal pathologies.

Capsule endoscopy - a non-invasive modality to investigate the GI tract: out with the old and in with the new?

INTRODUCTION

Capsule endoscopy has had significant development since it was introduced into the field of medicine in 2000. It is non-invasive, well tolerated, does not require sedation and is a first-line small bowel investigative modality. As it transits through the entire gastrointestinal (GI) tract, it has the potential to provide a pan-enteric examination.

AREAS COVERED

In this review we will discuss the new diagnostic modalities along with traditional methods which have been used for examination of the gastro intestinal (GI) tract. The main focus of this review will be on the use of capsule endoscopy for pan-enteric examination.

EXPERT OPINION

Capsule endoscopy is an accepted first-line investigation for the small bowel. Diagnostic sensitivity of the colon capsule is comparable to colonoscopy in controlled trials and is being evaluated in high-risk patients in routine clinical practice in national programs. Preliminary data suggest that a magnetic-controlled examination of the upper GI tract could be developed to enable a complete upper GI examination.

Magnetically controlled capsule endoscopy in one-time gastro-small intestinal joint examination: a two-centre experience

Background

The lesions of certain diseases are widely distributed in both stomach and small intestine, while the step-by-step strategy of gastroscopy followed by enteroscopy can be burdensome and costly. We aimed to determine if magnetically controlled capsule endoscopy (MCE) could be used in one-time gastro-small intestine (GSI) joint examination.

Methods

In this study, data of patients in Chinese PLA General Hospital and Changhai Hospital who underwent MCE GSI examination from January 2020 to August 2021 were retrospectively analysed. The primary outcome of this study was the success rate of one-time GSI joint examination, and secondary outcomes included visualization and cleanliness of gastrointestinal tract, gastrointestinal transit times, diagnostic yield and safety of MCE examination.

Results

A total of 768 patients were included. The success rate of one-time GSI joint examination was 92.58%. There were 94.92% MCEs observed > 90% gastric mucosa in the 6 anatomic landmarks. The rate of complete small bowel examination was 97.40%. The median gastric examination time, gastric transit time and small intestine transit time were 8.18 min, 63.89 min and 4.89 h, respectively. Magnetic steering of MCE significantly decreased gastric transit time (8.92 min vs. 79.68 min, P = 0.001) and increased duodenal lesion detection rate (13.47% vs. 6.26%, P = 0.001) when compared with non-magnetic steering group. Two capsules were retained and were removed by enteroscopy or spontaneously excreted.

Conclusions

MCE is feasible to complete GSI joint examination and the detection of both gastric and small intestinal diseases can be achieved simultaneously.

Trial registration Clinical Trial Registration ClinicalTrials.gov, ID: NCT05069233.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-022-02302-0.

Magnetic Soft Materials and Robots

In conventional classification, soft robots feature mechanical compliance as the main distinguishing factor from traditional robots made of rigid materials. Recent advances in functional soft materials have facilitated the emergence of a new class of soft robots capable of tether-free actuation in response to external stimuli such as heat, light, solvent, or electric or magnetic field. Among the various types of stimuli-responsive materials, magnetic soft materials have shown remarkable progress in their design and fabrication, leading to the development of magnetic soft robots with unique advantages and potential for many important applications. However, the field of magnetic soft robots is still in its infancy and requires further advancements in terms of design principles, fabrication methods, control mechanisms, and sensing modalities. Successful future development of magnetic soft robots would require a comprehensive understanding of the fundamental principle of magnetic actuation, as well as the physical properties and behavior of magnetic soft materials. In this review, we discuss recent progress in the design and fabrication, modeling and simulation, and actuation and control of magnetic soft materials and robots. We then give a set of design guidelines for optimal actuation performance of magnetic soft materials. Lastly, we summarize potential biomedical applications of magnetic soft robots and provide our perspectives on next-generation magnetic soft robots.

Design and Control of a Magnetically-Actuated Capsule Robot with Biopsy Function

OBJECTIVE

Wireless capsule endoscopy has been well used for gastrointestinal (GI) tract diagnosis. However, it can only obtain images and cannot take samples of GI tract tissues. In this study, we designed a magnetically-actuated biopsy capsule (MABC) robot for GI tract diagnosis.

METHODS

The proposed robot can achieve locomotion and biopsy functions under the control of external electromagnetic actuation (EMA) system. Two types of active locomotion can be achieved, plane motion refers to the robot rolling on the surface of the GI tract with a rotating uniform magnetic field. 3D motion refers to the robot moving in 3D space under the control of the EMA system. After reaching the target position, the biopsy needle can be sprung out for sampling and then retracted under a gradient magnetic field.

RESULTS

A pill-shaped robot prototype (15mm 32mm) has been fabricated and tested with phantom experiments. The average motion control error is 0.32mm in vertical direction, 3.3mm in horizontal direction, and the maximum sampling error is about 5.0mm. The average volume of the sampled tissue is about 0.35mm3.

CONCLUSION

We designed a MABC robot and proposed a control framework which enables planar and 3D spatial locomotion and biopsy sampling.

SIGNIFICANCE

The untethered MABC robot can be remotely controlled to achieve accurate sampling in multiple directions without internal power sources, paving the way towards precision sampling techniques for GI diseases in clinical procedures.

Upper gastrointestinal video capsule endoscopy: The state of the art

BACKGROUND

Video capsule can illuminate the entire gastrointestinal mucosa. Upper gastrointestinal capsule endoscopy (UGICE) has the potential to survey for oesophageal, gastric and duodenal pathology and determine whether biopsy or intervention is indicated.

AIMS

This review traces the evolution of foregut video capsule endoscopy.

METHODS

A broad literature research was performed independently by two investigators. Extracted articles were organized and evaluated to interpret all current data.

RESULTS

In contrast to small bowel capsule, UGICE required sequential innovations to deal with rapid oesophageal transit, the irregular shape of the stomach and unpredictable gastric peristalsis. Oesophageal capsule endoscopy required the development of a two-camera device operating at a high frame rate, and postural change was developed to improve image capture, especially at the level of the Z-line, thus providing good imaging of Barrett's oesophagus, erosive oesophagitis and oesophageal varices, with optimal patients' tolerance. UGICE in patients presenting to the emergency room with acute bleeding has demonstrated accuracy when deciding on the need for emergency intervention. The latest development of a high frame rate UGICE, designed to image the oesophagus, stomach and duodenum has overtaken dedicated oesophageal capsule development. Capsule control is possible by exposing a magnetised capsule to an external magnetic field, and early reports indicate high accuracy in the oesophagus and stomach with high levels of patient acceptability. There is little information on cost-benefit.

CONCLUSIONS

Capsule endoscopy offers gastroenterologists a new device to investigate the upper gastrointestinal tract with promising future potential.

Development and Application of Magnetically Controlled Capsule Endoscopy in Detecting Gastric Lesions

In the past 20 years, several magnetically controlled capsule endoscopes (MCCE) have been developed for the evaluation of gastric lesions, including NaviCam (ANKON), MiroCam-Navi (Intromedic), Endocapsule MGCE (Olympus and Siemens), SMCE (JIFU), and FAMCE (Jinshan). Although limited to observing esophageal and duodenal lesions and lacking the ability of biopsy, MCCE has the advantages of comfort, safety, no anesthesia, no risk of cross-infection, and high acceptability. Several high-quality RCTs showed that the diagnostic accuracy of MCCE is comparable to the traditional gastroscopy. Due to the nonnecessity of anesthesia, MCCE may be more suitable for the elderly with obvious comorbidities as well as children. With more evidences accumulated and more innovative technologies developed, MCCE is expected to be an important tool for screening of early gastric cancer or the diagnosis of gastric diseases.

Video Capsule Endoscopy and Device-Assisted Enteroscopy

Mark Hanscom Courtney Stead Harris Feldman Neil B. Marya David Cave.

Gastric examination using a novel three-dimensional magnetically assisted capsule endoscope and a hand-held magnetic controller: A porcine model study

Magnetically assisted capsule endoscopy (MACE) is a noninvasive procedure and can overcome passive capsule movement that limits gastric examination. MACE has been studied in many trials as an alternative to upper endoscopy. However, to increase diagnostic accuracy of various gastric lesions, MACE should be able to provide stereoscopic, clear images and to measure the size of a lesion. So, we conducted the animal experiment using a novel three-dimensional (3D) MACE and a new hand-held magnetic controller for gastric examination. The purpose of this study is to assess the performance and safety of 3D MACE and hand-held magnetic controller through the animal experiment. Subsequently, via the dedicated viewer, we evaluate whether 3D reconstruction images and clear images can be obtained and accurate lesion size can be measured. During real-time gastric examination, the maneuverability and visualization of 3D MACE were adequate. A polypoid mass lesion was incidentally observed at the lesser curvature side of the prepyloric antrum. The mass lesion was estimated to be 10.9 x 11.5 mm in the dedicated viewer, nearly the same size and shape as confirmed by upper endoscopy and postmortem examination. Also, 3D and clear images of the lesion were successfully reconstructed. This animal experiment demonstrates the accuracy and safety of 3D MACE. Further clinical studies are warranted to confirm the feasibility of 3D MACE for human gastric examination.

Capsule Endoscopy for Gastric Evaluation

Wireless capsule endoscopy was first developed to observe the small intestine. A small capsule can be swallowed and images of gastrointestinal tract are taken with natural movement of peristalsis. Application of capsule endoscopy for observing the stomach has also received much attention as a useful alternative to esophagogastroduodenoscopy, but anatomical characteristics of the stomach have demanded technical obstacles that need to be tackled: clear visualization and active movements that could be controlled. Different methods of controlling the capsule within stomach have been studied and magnetic manipulation is the only system that is currently used in clinical settings. Magnets within the capsule can be controlled with a hand-held magnet paddle, robotic arm, and electromagnetic coil system. Studies on healthy volunteers and patients with upper gastrointestinal symptoms have shown that it is a safe and effective alternative method of observing the stomach. This work reviews different magnetic locomotion systems that have been used for observation of the stomach as an emerging new application of wireless capsule endoscopy.

Capsule Endoscopy: Pitfalls and Approaches to Overcome

Capsule endoscopy of the gastrointestinal tract is an innovative technology that serves to replace conventional endoscopy. Wireless capsule endoscopy, which is mainly used for small bowel examination, has recently been used to examine the entire gastrointestinal tract. This method is promising for its usefulness and development potential and enhances convenience by reducing the side effects and discomfort that may occur during conventional endoscopy. However, capsule endoscopy has fundamental limitations, including passive movement via bowel peristalsis and space restriction. This article reviews the current scientific aspects of capsule endoscopy and discusses the pitfalls and approaches to overcome its limitations. This review includes the latest research results on the role and potential of capsule endoscopy as a non-invasive diagnostic and therapeutic device.

Current status and future developments of upper gastrointestinal tract capsule endoscopy

Capsule endoscopy has been widely used for the diagnosis of small bowel diseases due to its safety, noninvasiveness, and acceptability. Despite the potential benefits of capsule endoscopy, there are obvious challenges to capsule endoscopy application in the upper gastrointestinal tract, due to the fast transit speed in the esophagus and large space of the gastric cavity. With the development of innovative technologies, such as magnetic navigation and tethered capsule endoscopy, the indications for capsule endoscopy have recently been expanded. Various capsule endoscopes have been applied to clinical practice, and several state-of-the-art research-oriented designs and devices provide hope for further use in the diagnosis of upper gastrointestinal diseases. In this review, we will summarize the current status and future developments of upper gastrointestinal tract capsule endoscopy.

Magnetically Controlled Capsule Endoscopy Versus Conventional Gastroscopy: A Systematic Review and Meta-Analysis

BACKGROUND

The introduction of magnetically controlled capsule endoscopy overcame the restriction of passive capsule endoscopy movement, thus allowing an improved visualization of the gastrointestinal lumen, where other imaging studies seem to be unhelpful. The aim of this study is to systematically review the performance of magnetically controlled capsule endoscopy and evaluate its potential as a less invasive diagnostic method in the detection of gastric lesions.

METHODS

A systematic search was performed in PubMed (Medline), EMBASE, Google Scholar, Scopus, Who Global Health Library (GHL), Virtual Health Library (VHL), Clinicaltrials.gov, Cochrane Library, and ISI Web of Science databases. Proportion meta-analyses were performed to estimate the pooled sensitivity of magnetically controlled capsuled endoscopy in the detection of gastrointestinal lesions.

RESULTS

Among the 3026 studies that were initially assessed, 7 studies were finally included, with a total of 916 patients and 745 gastric lesions. The mean capsule endoscopy examination time was 21.92±8.87 minutes. The pooled overall sensitivity of magnetically controlled capsule endoscopy was 87% [95% confidence interval (CI), 84%-89%]. Subgroup analysis showed that the sensitivity of identifying gastric ulcers was 82% (95% CI: 71%-89%), gastric polyps was 82% (95% CI: 76%-87%), and gastric erosions was 95% (95% CI: 86%-98%). In general, magnetically controlled capsule endoscopy was well tolerated by the participants with minimal adverse events.

CONCLUSION

The magnetically controlled capsule endoscopy demonstrated an acceptable sensitivity of identifying gastric lesions. Further prospective comparative studies are needed to identify the risks and benefits of this new technique, as well as to determine its role as a replacement for conventional gastroscopy.

Examination of Entire Gastrointestinal Tract: A Perspective of Mouth to Anus (M2A) Capsule Endoscopy

Capsule endoscopy (CE) is the only non-invasive diagnostic tool that enables the direct visualization of the gastrointestinal (GI) tract. Even though CE was initially developed for small-bowel investigation, its clinical application is expanding, and technological advances continue. The final iteration of CE will be a mouth to anus (M2A) capsule that investigates the entire GI tract by the ingestion of a single capsule. This narrative review describes the current developmental status of CE and discusses the possibility of realizing an M2A capsule and what needs to be overcome in the future.

Orthogonal Optimal Design of Multiple Parameters of a Magnetically Controlled Capsule Robot

Magnetically controlled capsule robots are predominantly used in the diagnosis and treatment of the human gastrointestinal tract. In this study, based on the permanent magnet method, magnetic driving and fluid measurement systems for in-pipe capsule robots were established. Using computational fluid dynamics (CFD) and particle image velocimetry (PIV), the fluid velocity and vorticity in the pipe of the capsule robot were calculated and measured. The running characteristics of the capsule robot were numerically analyzed in the curved pipe and the peristaltic flow. Furthermore, the range and variance method of orthogonal design was used to analyze the influence of four typical parameters (namely, pipe diameter, robotic translational speed, robotic rotational speed, and fluid viscosity) on the three operating performance indicators of the capsule robot (namely, the forward resistance of the robot, fluid turbulent intensity near the robot, and maximum fluid pressure to the pipe wall). In this paper, the relative magnitude and significance of the influence of each typical parameter on different performance indicators of the robot are presented. According to the different performance requirements of the robot, the different four parameter combinations are optimized. It is hoped that this work provides a reference for the selection of the appropriate mucus, translational speed, and rotational speed of the robot when it is working in pipes with different diameters.

Diagnostic yield of esophagogastroduodenoscopy in France

BACKGROUND AND STUDY AIMS

Large scale data on esophagogastroduodenoscopy (EGD) in Western countries are scarce. We conducted a prospective study on the diagnostic yield of upper gastrointestinal endoscopy in France.

PATIENTS AND METHODS

An online questionnaire was sent to all French gastroenterologists practicing endoscopy. Data from EGDs performed during one week were collected. A statistical extrapolation of the results to a whole year was performed.

RESULTS

342 gastrointestinal endoscopists, representative of the population of French gastroenterologists, provided data on 2735 EGDs, corresponding to 1 006 316 (95%CI=937 080-1 075 552) procedures for the entire year. 1770 (64.7%) EGDs were performed under sedation or general anesthesia, and 930 (34%) were associated with a colonoscopy. 896 (32.8%) EGDs were normal. Hiatal hernia and esophagitis were the most frequent esophageal diagnoses, in 496 (18.1%) and 374 (13.7%) cases, respectively. Barrett's esophagus was diagnosed in 109 (4%) patients. Among gastric lesions, endoscopic gastritis was reported in 572 (20.9%) patients; ulcer, polyps, and suspected malignancy in 78 (2.9%), 62 (2.3%), and 19 (0.7%), respectively. 1597 (58.4%) EGDs included mucosal biopsies, and 141 (5.1%) were associated with a therapeutic procedure.

CONCLUSIONS

We report nationwide prospective data on upper gastrointestinal endoscopy practice in France. Our data suggest that about 300 000 normal EGDs each year in France could potentially be avoided by a diagnostic strategy relying on upper GI capsule endoscopy, providing significant relief on healthcare practitioners.

Novel Clinical Applications and Technical Developments in Video Capsule Endoscopy

Video capsule endoscopy is entering its third decade. After slow acceptance, it has become the gold standard in diagnosing small intestinal disorders. This article summarizes new practical applications for capsule endoscopy outside the small intestine. From 2 randomized controlled trials, it is becoming clear that it has a role in the management of patients with hematemesis and nonhematemesis bleeding. Under active investigation are novel applications of capsule technology, including the potential ability to sample luminal contents or tissue, self-propelled capsules, incorporation of other imaging techniques beyond white light, such as ultrasound and fluorescents, and the possibility of drug delivery.

Role of Video Capsule in Small Bowel Bleeding

Video capsule endoscopy has an essential role in the diagnosis and management of small bowel bleeding and is the first-line study recommended for this purpose. This article reviews the risk factors for small bowel bleeding, optimal timing for video capsule endoscopy testing, and algorithms recommended for evaluation. Used primarily for the assessment of nonacute gastrointestinal blood loss, video capsule endoscopy has an emerging role for more urgent use in emergency settings and in special populations. Future software incorporation of neural networks to enhance lesion detection will likely result in an augmented role of video capsule endoscopy in small bowel bleeding.

Detachable string magnetically controlled capsule endoscopy for complete observation of the upper gastrointestinal tract

BACKGROUND

Wireless magnetically controlled capsule endoscopy (WMCCE) was feasible, well tolerated, highly acceptable, and had high consistency in diagnosis of gastric diseases with esophagogastroduodenoscopy (EGD). But WMCCE is not suitable for inspection of the esophagus. We developed detachable string magnetically controlled capsule endoscopy (DS-MCCE) to observe gastroesophageal diseases.

METHODS

A total of 60 volunteers were enrolled. Thirty participants underwent DS-MCCE, and the other 30 underwent WMCCE. The primary outcome measures included swallowing time, esophageal transit time, the whole examination time, grade of air-bubble interference on esophageal, gastric preparation, visualization of Z-line and gastric mucosa, and discomfort scores.

RESULTS

The esophageal time (222.53 ± 107.53 s vs. 49.50 ± 34.90 s, P < 0.001) and the whole examination time (26.53 ± 6.33 min vs. 15.97±4.90 min, P < 0.001) in DS-MCCE group were longer than in WMCCE group. DS-MCCE had a significantly better visualization of Z-line visualization. Visualization of the gastric mucosa was assessed as good in 24 (80%) participants for DS-MCCE and 26 (86.6%) for WMCCE, moderate in 6 (20%) with DS-MCCE as compared with 4 (13.3%) with WMCCE. The visualization of gastric cardia for DS-MCCE was better than for WMCCE (100 vs 80%, P = 0.024). The visualization of gastric angle, antrum, and pylorus in DS-MCCE group was not as good as in WMCCE group (80 vs. 100%, 80 vs. 100%, 83.3 vs. 100%, P = 0.024).

CONCLUSIONS

DS-MCCE is feasible and well tolerated in the diagnosis of gastroesophageal diseases. For people who cannot stand conventional EGD or with contraindication of EGD, DS-MCCE may be an excellent alternative screening modality.

Feasibility of a second-generation colon capsule in visualization of the upper gastrointestinal tract

Background

Capsule endoscopy for visualization of the entire gastrointestinal tract is a challenge. A second-generation colon capsule endoscopy system (CCE-2) performed well in the colon and small intestine, but its utility in the upper gastrointestinal duct is not clear. We evaluated the use of the CCE-2 in the visualization of the upper gastrointestinal tract.

Methods

We performed a retrospective study and further evaluated CCE-2 images using the typical landmarks of esophagus and stomach. The two imagers located at each end of the CCE-2 system were defined as imager1 (green) and imager2 (yellow). Two endoscopists read the images, and they were blinded to the other reader’s results. All of the images from the two imagers were separately reviewed.

Results

Images from 127 subjects were analyzed. This study demonstrated the comprehensive visualization of 71.7% of esophageal landmarks and 89.8% of gastric landmarks using the CCE-2. The two CCE-2 imagers were not identical, and the lighter imager (imager2, yellow) was superior to the heavier imager (imager1, green) (78% vs. 33.1%) in the stomach. Compared with the use of one imager, the use of two imagers was superior (two-imager vs. imager1, 89.8% vs. 33.1%; two-imager vs. imager2, 89.8% vs. 78%) in the stomach. Two-imager combination analysis detected a total of 160 positive findings. In contrast, single-imager analysis with imager1 and imager2 detected 133 and 137 findings, respectively. Two-imager combination analysis provided 20.3% and 16.8% more findings than imager1 and imager2, respectively. The two imagers complemented each other to detect more lesions.

Conclusions

The CCE-2 system is feasible for use in the upper gastrointestinal tract and may be considered an optional tool for upper gastrointestinal imaging. This system may represent a good choice for complete gastrointestinal duct screening. Compared with the use of one imager, the two-imager combination provided improved upper gastrointestinal tract mucosal visualization.

Posture Dynamic Modeling and Stability Analysis of a Magnetic Driven Dual-Spin Spherical Capsule Robot

In order to realize the intervention operation in the unstructured and ample environments such as stomach and colon, a dual-spin spherical capsule robot (DSCR) driven by pure magnetic torque generated by the universal rotating magnetic field (URMF) is proposed. The coupled magnetic torque, the viscoelastic friction torque, and the gravity torque were analyzed. Furthermore, the posture dynamic model describing the electric-magnetic-mechanical-liquid coupling dynamic behavior of the DSCR in the gastrointestinal (GI) tract was established. This model is a second-order periodic variable coefficient dynamics equation, which should be regarded as an extension of the Lagrange case for the dual-spin body system under the fixed-point motion, since the external torques were applied. Based on the Floquet-Lyapunov theory, the stability domain of the DSCR for the asymptotically stable motion and periodic motion were obtained by investigating the influence of the angular velocity of the URMF, the magnetic induction intensity, and the centroid deviation. Research results show that the DSCR can realize three kinds of motion, which are asymptotically stable motion, periodic motion, and chaotic motion, according to the distribution of the system characteristic multipliers. Moreover, the posture stability of the DSCR can be improved by increasing the angular velocity of the URMF and reducing the magnetic induction intensity.

Frontiers of Robotic Gastroscopy: A Comprehensive Review of Robotic Gastroscopes and Technologies

Simple Summary

With the rapid advancements of medical technologies and patients’ higher expectations for precision diagnostic and surgical outcomes, gastroscopy has been increasingly adopted for the detection and treatment of pathologies in the upper digestive tract. Correspondingly, robotic gastroscopes with advanced functionalities, e.g., disposable, dextrous and not invasive solutions, have been developed in the last years. This article extensively reviews these novel devices and describes their functionalities and performance. In addition, the implementation of artificial intelligence technology into robotic gastroscopes, combined with remote telehealth endoscopy services, are discussed. The aim of this paper is to provide a clear and comprehensive view of contemporary robotic gastroscopes and ancillary technologies to support medical practitioners in their future clinical practice but also to inspire and drive new engineering developments.

Abstract

Upper gastrointestinal (UGI) tract pathology is common worldwide. With recent advancements in robotics, innovative diagnostic and treatment devices have been developed and several translational attempts made. This review paper aims to provide a highly pictorial critical review of robotic gastroscopes, so that clinicians and researchers can obtain a swift and comprehensive overview of key technologies and challenges. Therefore, the paper presents robotic gastroscopes, either commercial or at a progressed technology readiness level. Among them, we show tethered and wireless gastroscopes, as well as devices aimed for UGI surgery. The technological features of these instruments, as well as their clinical adoption and performance, are described and compared. Although the existing endoscopic devices have thus far provided substantial improvements in the effectiveness of diagnosis and treatment, there are certain aspects that represent unwavering predicaments of the current gastroenterology practice. A detailed list includes difficulties and risks, such as transmission of communicable diseases (e.g., COVID-19) due to the doctor–patient proximity, unchanged learning curves, variable detection rates, procedure-related adverse events, endoscopists’ and nurses’ burnouts, limited human and/or material resources, and patients’ preferences to choose non-invasive options that further interfere with the successful implementation and adoption of routine screening. The combination of robotics and artificial intelligence, as well as remote telehealth endoscopy services, are also discussed, as viable solutions to improve existing platforms for diagnosis and treatment are emerging.

A New Active Locomotion Capsule Endoscopy under Magnetic Control and Automated Reading Program

Capsule endoscopy (CE) is the first-line diagnostic modality for detecting small bowel lesions. CE is non-invasive and does not require sedation, but its movements cannot be controlled, it requires a long time for interpretation, and it has lower image quality compared to wired endoscopy. With the rapid advancement of technology, several methods to solve these problems have been developed. This article describes the ongoing developments regarding external CE locomotion using magnetic force, artificial intelligence-based interpretation, and image-enhancing technologies with the CE system.

Second-generation magnetically controlled capsule gastroscopy with improved image resolution and frame rate: a randomized controlled clinical trial (with video)

BACKGROUND AND AIMS

Compared with conventional endoscopy, magnetically controlled capsule gastroscopy (MCCG) can be further optimized in gastric examination time and complete visualization of upper GI (UGI) mucosa. The second-generation MCCG (MCCG-2) was developed with higher image resolution and adaptive frame rate, and we aimed to evaluate its clinical availability for UGI examination in this study.

METHODS

Consecutive patients undergoing MCCG examination between May to June 2019 were prospectively enrolled and randomized to swallow the first-generation MCCG (MCCG-1) or MCCG-2 in a 1:1 ratio. The main outcomes included visualization of the esophagus and duodenum, operation-related parameters, image quality, maneuverability, detection of lesions, and safety evaluation.

RESULTS

Eighty patients were enrolled. In the MCCG-2 group, frames captured for esophageal mucosa and Z-line were 171.00 and 2.00, significantly increased from those in the MCCG-1 group (97.00 [P = .002] and .00 [P = .028], respectively). The gastric examination time was shortened from 7.78 ± .97 minutes to 5.27 ± .74 minutes (P < .001), with the total running time of the capsule extended from 702.83 minutes to 1001.99 minutes (P < .001). MCCG-2 also greatly improved the image quality (P < .001) and maneuverability (P < .01). No statistical difference existed in the detection of lesions between the 2 groups, and no adverse events occurred.

CONCLUSIONS

MCCG-2 showed better performance in mucosal visualization, examination duration, and maneuverability, making better diagnosis of UGI diseases a possibility. (Clinical trial registration number: NCT03977935.).

Standing-type magnetically guided capsule endoscopy versus gastroscopy for gastric examination: multicenter blinded comparative trial

AIM

To compare feasibility and safety after gastrointestinal checkup by standing-type magnetically controlled capsule endoscopy (SMCE) and conventional gastroscopy.

METHODS

This was a prospective multicenter, blinded study that compared SMCE with gastroscopy in patients from April 2018 to July 2018. All patients first underwent SMCE and then subsequently had gastroscopy with i.v. anesthesia. We calculated the compliance rates of gastric lesion detection by SMCE using gastroscopy as the standard. Capsule retention rate, incidence of adverse events, and patient satisfaction were documented throughout the study.

RESULTS

One hundred and sixty-one patients who completed SMCE and gastroscopy were included in the analysis. Positive compliance rate among SMCE and gastroscopy was 92.0% (95% CI: 80.77%-97.78%). Negative compliance rate was 95.5% (89.80%, 98.52%). Moreover, overall compliance rate was 94.41% (89.65%, 97.41%). Sixty-four pathological outcomes were identified. Of these 64 outcomes, 50 were detected by both procedures. The gastroscopy method neglected seven findings (such as five erosions, one polyp, and one ulcer). Furthermore, SMCE also overlooked seven lesions (i.e. one erosion, two polyps, one atrophy, and three submucosal tumors). Capsule retention or related adverse events were not reported.

CONCLUSION

Standing-type magnetically controlled capsule endoscopy provides equivalent agreement with gastroscopy and may be useful for screening of gastric illnesses without any anesthesia.

Diagnosis of Barrett's esophagus and esophageal varices using a magnetically assisted capsule endoscopy system

BACKGROUND AND AIMS

Magnetically assisted capsule endoscopy (MACE) potentially offers a comfortable, patient friendly, and community-based alternative to gastroscopy (EGD). This pilot study aims to explore whether this approach can be used to accurately diagnose Barrett's esophagus (BE) and esophageal varices.

METHOD

The MiroCam Navi capsule system was used to examine the upper GI tract in patients due to undergo a clinically indicated EGD. A total of 50 participants were enrolled: 34 had known pathology (17 BE, 17 esophageal varices [EV]) and 16 controls. Patients underwent the MACE procedure with the operator blinded to the indication and any previous endoscopic diagnoses. The subsequent EGD was performed by an endoscopist blinded to the MACE findings. Diagnostic yield, comfort, and patient preference between the 2 modalities were compared.

RESULTS

The mean age of the participants was 61 years, the male/female ratio was 2.1:1, the mean body mass index was 29.5 kg/m², and the average chest measurement was 105.3 cm. Forty-seven patients underwent both procedures; 3 patients were unable to swallow the capsule. With the use of the magnet, it was possible to hold the capsule within the esophagus for a mean duration of 190 seconds and up to a maximum of 634 seconds. A correct real-time MACE diagnosis was made in 11 of 15 patients with EV (sensitivity 73.3% [95% confidence interval (CI), 44.9%-92.2%] and specificity 100% [95% CI, 89.1%-100%]) and 15 of 16 patients with BE (sensitivity 93.8% [95% CI, 69.8%-99.8%] and specificity of 100% [95% CI, 88.8%-100%]). MACE was considered more comfortable than conventional endoscopy (P < .0001); the mean score was 9.2 for MACE compared with 6.7 for EGD when assessed on a 10-point scale. No MACE- or EGD-related adverse events occurred.

CONCLUSION

This pilot study demonstrates that MACE is both safe and well tolerated by patients. Accuracy for the diagnosis of BE was high, and therefore MACE may have a role in screening for this condition. (Clinical trial registration number: NCT02852161.).

Optimizing the performance of magnet-controlled capsule endoscopy based on radiological and gastroscopic modeling

Routine use of magnet-controlled capsule endoscopy of the stomach has been limited by the inadequate views of specific stomach regions. In the present study, radiology and upper gastrointestinal endoscopy (UGIE) were used to determine optimal subject body positioning and suitable external control magnet placement for capsule endoscopy. Healthy adult volunteers were subjected to upper gastrointestinal X-ray radiography (n=5), spiral computed tomography with volume reconstruction (n=4) or UGIE (n=1). Stomach fundus-to-body (FB) and body-to-antrum (BA) angles were compared when subjects were supine, prone, lying on their left side and on their right side, and when they were standing upright. Vertical distances from the surface of the body to the distal points of the fundus and antrum were also compared in this range of subject positions. Obtuse angles were considered the most beneficial for capsule movement and short vertical distances were considered desirable for optimizing magnetic force. The FB angle was sharply acute in the supine position, relatively open where subjects were on their side, and almost 180° in the standing position. The BA angle was obtuse in the standing position but acute in all other positions. With the subject in any position, the left lower lateral chest had the shortest distance to the fundus, while the ventral wall was closest to the antrum. The present modeling analysis indicates that standing is superior to all decubitus positions for magnetic-capsule endoscopy, including the commonly used supine position. Both the abdominal anterior wall and left lateral lower chest appeared to be advantageous locations for external control magnet placement.

Human gastric magnet-controlled capsule endoscopy conducted in a standing position: the phase 1 study

Background

Current magnet-controlled capsule endoscopy (MCE) for the stomach is not yet satisfactory with respect to navigation control, especially in the gastric fundus and cardia. A newly developed MCE system conducted in a standing rather than supine position may improve capsule maneuverability within the stomach. The aim of this phase 1 study was to assess the feasibility and safety of this system for examining the human stomach in healthy volunteers.

Methods

A cohort of 31 healthy volunteers were enrolled. Each swallowed a capsule after drinking water and gas producing agents intended to produce distention. Under the newly developed standing MCE system, subjects were examined endoscopically while standing with external guide magnets placed on the abdominal wall and left lower chest. Safety, gastric preparation, maneuverability, visualization of anatomical landmarks and the gastric mucosa, and examination time were the primary parameters assessed. The gastric preparation and examination procedures were well accepted by the subjects and there were no adverse events.

Results

Gastric examination took 27.8 ± 8.3 min (12–45 min). Gastric cleanliness was good in 24 participants (77.4%) and moderate in 7 participants (22.6%). Gastric distention was good in all of 31 participants (100%). Capsule maneuverability was also graded as good in all 31 subjects (100%), and manipulation in the fundus and cardia regions was as easy as that in the antrum and body. Visualization of the gastric cardia, fundus, body, angulus, antrum and pylorus was assessed subjectively as complete in all 31 subjects (100%). Visualization of the gastric mucosa was also good (> 75%) in all 31 subjects (100%). In areas where the mucosa could not be visualized, the low visibility was due to opaque fluid or foam. Polyps and erosive lesions were found in 25 subjects.

Conclusion

MCE of the stomach conducted in a standing position is feasible and safe with satisfactory maneuverability.

Clinical Efficiency and Safety of Magnetic-Controlled Capsule Endoscopy for Gastric Diseases in Aging Patients: Our Preliminary Experience

BACKGROUND

The elderly assess higher incidence of gastric diseases and may meet challenges and contraindications when flexible esophagogastroduodenoscopy intubating. Magnetic-controlled capsule endoscopy (MCE) is declared as a promising alternative, but its applications in elderly population do not attach enough importance.

AIMS

To explore MCE's efficiency and safety in the elderly.

METHODS

A single-center retrospective study has been conducted. Data from the elderly group (>65 year-old) who underwent MCE examination, including indications, MCE outcomes, gastric conditions, evaluations from MCE manipulators and endoscopists, subjective discomforts, adverse events, etc., had been collected, then analyzed, and compared with the ones from the middle-aged group (>40, ≤ 65 year-old).

RESULTS

During April 2015 and September 2018, 98 elderly patients and 72 middle-aged patients underwent MCE examination. In the elderly, the indications included poor physical condition (28.6%), severe angiocardiopathy (39.8%), EGD rejection (13.3%), severe respiratory disorder (8.2%), craniocerebral injury (8.2%), and allergy to anesthetics (2.0%). Rate of complete gastric observation and positive finding were 98.0% and 72.4% (vs. middle-aged group, 94.4%, 56.9%, P = 0.220, 0.035), and gastric conditions showed relatively inferior. Gastric preparation and MCE procedure were generally tolerated, but three elderly patients (3.1%) experienced capsule blockage in stomach.

CONCLUSIONS

Our preliminary data support that MCE offers considerable benefit and is general safe for the elderly. We hope such data promote greater awareness of innovative attempts for the specific elderly, and expect multi-center, large-scale trials with randomized controlled design bring optimized strategies for better gastric visibility, efficacy and lower potential risk.

Magnetically Guided Capsule Endoscopy in Pediatric Patients with Abdominal Pain

Background and Aims

Magnetically guided capsule endoscopy (MGCE) offers a noninvasive method of evaluating both the gastric cavity and small intestine; however, few studies have evaluated MGCE in pediatric patients. We investigated the diagnostic efficacy of MGCE in pediatric patients with abdominal pain.

Patients and Methods

We enrolled 48 patients with abdominal pain aged 6–18 years. All patients underwent MGCE to evaluate the gastric cavity and small intestine.

Results

The cleanliness of the gastric cardia, fundus, body, angle, antrum, and pylorus was assessed satisfactorily in 100%, 85.4%, 89.6%, 100%, 97.9%, and 100% of patients, respectively. The subjective percentage visualization of the gastric cardia, fundus, body, angle, antrum, and pylorus was 84.8%, 83.8%, 88.5%, 87.7%, 95.2%, and 99.6%, respectively. Eighteen (37.5%) patients had 19 gastrointestinal tract lesions: one esophageal, three in the gastric cavity, and 15 in the small intestine. No adverse events occurred during follow-up.

Conclusions

MGCE is safe, convenient, and tolerable for evaluating the gastric cavity and small intestine in pediatric patients. MGCE can effectively diagnose pediatric patients with abdominal pain.

Repetitive Position Change Improves Gastric Cleanliness for Magnetically Controlled Capsule Gastroscopy

BACKGROUND AND AIMS

Good gastric preparation is essential for magnetically controlled capsule gastroscopy (MCCG) examination. This study aims to determine if repetitive position change after dimethicone premedication could further improve gastric cleanliness for MCCG.

METHODS

Consecutive patients referred for MCCG in our center from May 7 to May 31, 2018 were prospectively enrolled and randomized to undergo repetitive position change for 15 min (position change group) or not (conventional group) after ingesting dimethicone. Primary outcome was gastric cleanliness score and secondary outcomes were detection rate of positive findings, number of lesions per patient, gastric examination time, and safety of MCCG.

RESULTS

Totals of 43 and 40 were included in the position change and conventional groups, respectively. Gastric cleanliness score in the position change group was significantly higher than in the conventional group (21.2 ± 1.0 vs. 18.6 ± 2.0, P  < 0.001), as was the proportion of acceptable gastric cleanliness (gastric cleanliness score ≥ 18) (100% vs. 72.5%, P  < 0.001). There was no statistical difference in detection rate of positive findings between the two groups (27.9% vs. 27.5%, P  = 0.97). In the position change group, the gastric examination time was significantly reduced (13.2 ± 4.0 vs. 15.3 ± 5.1, P = 0.043). No adverse events were observed.

CONCLUSIONS

Repetitive position change after dimethicone premedication significantly improves gastric cleanliness for MCCG examination. Clinical Trial Registration ClinicalTrials.gov, ID: NCT03514966.

Clinical application of magnetically controlled capsule gastroscopy in gastric disease diagnosis: recent advances

Magnetically controlled capsule gastroscopy (MCCG) is a novel system primarily used for the diagnosis of gastric disease. It consists of an endoscopic capsule with magnetic material inside, external guidance magnet equipment, data recorder and computer workstation. Several clinical trials have demonstrated that MCCG is comparable in accuracy in diagnosing gastric focal disease when compared to conventional gastroscopy. Further clinical studies are needed to test the diagnostic accuracy and improve the functioning of MCCG. This novel MCCG system could be a promising alternative for screening for gastric diseases, with the advantages of no anesthesia required, comfort and high acceptance across populations.

Preliminary study of magnetically controlled capsule gastroscopy for diagnosing superficial gastric neoplasia

BACKGROUND

Magnetically controlled capsule gastroscopy (MCCG) is a newly developed non-invasive method designed for gastric examination. Although favorable diagnostic accuracy has been reported, there is little if any data about its ability to diagnose gastric cancer.

AIMS

To compare the detectability of superficial gastric neoplasia by MCCG and gastroscopy.

METHODS

This study was a self-controlled comparison study. Ten subjects diagnosed with superficial gastric neoplasia and scheduled to undergo endoscopic submucosal dissection (ESD) at a tertiary hospital were prospectively invited for an MCCG examination. The diagnostic agreement of MCCG, ESD and pathology were compared, including location, size and endoscopic appearance of the lesions.

RESULTS

Of the 10 enrolled patients, 6 were confirmed as having early gastric cancer/high-grade intraepithelial neoplasia, 2 gastric low-grade intraepithelial neoplasia (LGIN), 1 tubular adenoma with LGIN and 1 neuroendocrine tumor. The per-patient and per-lesion sensitivities of MCCG for superficial gastric neoplasia detection were 100% and 91.7%. Location and size of the lesions were compared favorably to gastroscopy whilst one cardiac lesion was missed. Endoscopic appearances of these lesions observed on MCCG and EGD demonstrated good consistency. No adverse events were observed.

CONCLUSION

With good gastric preparation and careful examination of stomach, MCCG is able to detect superficial gastric neoplasms.

Optimising the performance and interpretation of small bowel capsule endoscopy

Small bowel capsule endoscopy has become a commonly used tool in the investigation of gastrointestinal symptoms and is now widely available in clinical practice. In contrast to conventional endoscopy, there is a lack of clear consensus on when competency is achieved or the way in which capsule endoscopy should be performed in order to maintain quality and clinical accuracy. Here we explore the evidence on the key factors that influence the quality of small bowel capsule endoscopy services.

Screening for gastric cancer with magnetically controlled capsule gastroscopy in asymptomatic individuals

BACKGROUND AND AIMS

Gastric cancer (GC) is the fourth most common cancer and the fourth leading cause of cancer death worldwide. In some Asian countries, screening EGD has greatly improved the survival rate. However, patients' discomfort and the need for sedation may limit adherence to screening programs. Previous studies have shown good tolerance and good agreement of magnetically controlled capsule gastroscopy (MCCG) with EGD. This study was designed to assess the application of MCCG in GC detection in an asymptomatic population.

METHODS

In this observational cohort study, 3182 asymptomatic individuals undergoing MCCG in 99 participating medical examination centers from April to December 2016 were enrolled. Patients with ulcers and suspected malignancies were referred for gastroscopy and biopsy. The detection rate of GC and focal lesions were used to explore the application of MCCG in asymptomatic individuals.

RESULTS

Seven patients (0.22%) were diagnosed with GC among the enrolled 3182 individuals, accounting for 0.74% (7/948) in patients over 50 years. No gender disparity was observed. EGD and biopsy confirmed adenocarcinoma in all cases of suspected malignancy. Benign polyps, gastric ulcers, and submucosal tumors were found in 10.4%, 4.9%, and 3.6% of patients, respectively. There was a trend for the prevalence of focal lesions to increase with age. MCCG examination proved to be safe.

CONCLUSIONS

MCCG can detect cancer and benign lesions and is safe and clinically feasible in a large population. Studies of its role in a screening program should be considered.

Upper gastrointestinal tract capsule endoscopy using a nurse-led protocol: First reported experience

AIM

To test the feasibility and performance of a novel upper gastrointestinal (GI) capsule endoscope using a nurse-led protocol.

METHODS

We conducted a prospective cohort analysis of patients who declined gastroscopy (oesophagogastroduodenoscopy, OGD) but who consented to upper GI capsule endoscopy. Patients swallowed the upper GI capsule following ingestion of 1 liter of water (containing simethicone). A series of positional changes were used to exploit the effects of water flow and move the upper GI capsule from one gravity-dependent area to another using a nurse-led protocol. Capsule transit time, video reading time, mucosal visualisation, pathology detection and patient tolerance was evaluated.

RESULTS

Fifty patients were included in the study. The mean capsule transit times in the oesophagus and stomach were 28 s and 68 min respectively. Visualisation of the following major anatomical landmarks was achieved (graded 1-5: Poor to excellent): Oesophagus, 4.8 (± 0.5); gastro-oesophageal junction (GOJ), 4.8 (± 0.8); cardia, 4.8 (± 0.8); fundus, 3.8 (± 1.2); body, 4.5 (± 1); antrum, 4.5 (± 1); pylorus, 4.7 (± 0.8); duodenal bulb, 4.7 (± 0.7); second part of the duodenum (D2), 4.7 (± 1). The upper GI capsule reached D2 in 64% of patients. The mean video reading time was 48 min with standard playback mode and 20 min using Quickview (P = 0.0001). No pathology was missed using Quickview. Procedural tolerance was excellent. No complications were seen with the upper GI capsule.

CONCLUSION

The upper GI capsule achieved excellent views of the upper GI tract. Future studies should compare the diagnostic accuracy between upper GI capsule and OGD.