Diagnostic yield of magnetically assisted capsule endoscopy versus gastroscopy in recurrent and refractory iron deficiency anemia

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.

Resistance model of an active capsule endoscope in a peristaltic intestine

In the past studies, the resistance of magnetically controlled capsules running through the small intestine has been modeled assuming that the small intestine was a circular tube with a constant diameter. Peristalsis is an important character of the human gastrointestinal system, and it would result in some changes in the diameter of the intestine, meaning that the existing resistance models would no longer be applicable. In this paper, based on the assumption that intestinal peristalsis is actually a sinusoidal wave, a resistance model of the capsule running in the peristaltic intestine is established, and then it is validated experimentally. The model provides a realistic foundation for the optimization and control of the magnetically controlled endoscopy.

The use of magnet-controlled capsule endoscopy as the initial diagnostic tool in patients with acute upper gastrointestinal bleeding

BACKGROUND

The latest magnet-controlled capsule endoscopy (MCCE) system can examine the water-distended stomach, duodenum, and the small bowel. We assessed the use of MCCE as the first diagnostic tool in patients with acute upper gastrointestinal bleeding (AUGIB).

METHODS

This was a prospective cohort study that enrolled patients admitted with AUGIB from two teaching hospitals. Patients underwent MCCE as the initial diagnostic modality. Our primary endpoint was the diagnostic yield of MCCE. The subsequent care of these patients was guided by MCCE findings.

RESULTS

Of 100 enrolled patients, 99 (mean age 54 years, 70.7% men) with a median Glasgow-Blatchford score of 6 (IQR 3-9) underwent MCCE. In three patients, MCCE found active bleeding (two duodenal ulcers and Dieulafoy's lesion). The overall diagnostic yield of MCCE was 95.8% (92 lesions in 96 patients); five in the esophagus (Mallory Weiss tears 2, varices 1, and esophagitis 2), 51 in the stomach (gastric erosions 26, gastric ulcers 14, cancer 3, GIST 3, gastric polyps 3, antral vascular ectasia 1,angiodysplasia 1), 32 in the duodenum (ulcers 28, erosions 3, polyp 1), and four in the small bowel (ulcers 2, an erosion with a nonbleeding vessel 1, Meckel's diverticulum 1). Fifty-two (52.5%) patients were discharged without endoscopy. Forty-five (45.5%) patients underwent inpatient esophagogastroduodenoscopy (EGD), which found an antral ulcer and six duodenal ulcers in addition.

CONCLUSIONS

In stable patients with AUGIB, MCCE can be used as a diagnostic tool. EGD should follow in patients with an inadequate view of the duodenum.

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.

A novel intelligent chromo capsule endoscope for the diagnosis of neoplastic lesions in the gastrointestinal tract

Background

Chromoendoscopy has not been fully integrated into capsule endoscopy. This study aimded to develop and validate a novel intelligent chromo capsule endoscope (ICCE).

Methods

The ICCE has two modes: a white-light imaging (WLI) mode and an intelligent chromo imaging (ICI) mode. The performance of the ICCE in observing colors, animal tissues, and early gastrointestinal (GI) neoplastic lesions in humans was evaluated. Images captured by the ICCE were analysed using variance of Laplacian (VoL) values or image contrast evaluation.

Results

For color observation, conventional narrow-band imaging endoscopes and the ICI mode of the ICCE have similar spectral distributions. Compared with the WLI mode, the ICI mode had significantly higher VoL values for animal tissues (2.154 ± 1.044 vs 3.800 ± 1.491, P = 0.003), gastric precancerous lesions and early gastric cancers (2.242 ± 0.162 vs 6.642 ± 0.919, P < 0.001), and colon tumors (3.896 ± 1.430 vs 11.882 ± 7.663, P < 0.001), and significantly higher contrast for differentiating tumor and non-tumor areas (0.069 ± 0.046 vs 0.144 ± 0.076, P = 0.005). More importantly, the sensitivity, specificity, and accuracy of the ICI mode for early GI tumors were 95.83%, 91.67%, and 94.64%, respectively, which were significantly higher than the values of the WLI mode (78.33% [P < 0.001], 77.08% [P = 0.01], and 77.98% [P < 0.001], respectively).

Conclusions

We successfully integrated ICI into the capsule endoscope. The ICCE is an innovative and useful tool for differential diagnosis based on contrast-enhanced images and thus has great potential as a superior diagnostic tool for early GI tumor detection.

Cost comparison of oral, transnasal and magnet assisted capsule endoscopy in the examination of the upper gastrointestinal tract in patients with dyspepsia

Introduction

Conventional oral upper gastrointestinal (GI) endoscopy can obe uncomfortable. By comparison, transnasal endoscopy (TNE) and magnet assisted capsule endoscopy (MACE) have superior tolerability. A cost comparison of competing upper GI endoscopic modalities have yet to be performed.

Methods

We performed a cost comparison study of oral, TNE and MACE by a combination of activity-based costing and averaging of fixed costs over 24 481 upper GI endoscopies performed for dyspepsia over a 10-year period.

Results

On average, 9.4 procedures were performed daily. TNE was cheapest at €125.90 per procedure, costing 30% less than oral endoscopy at €184.10 and threefold cheaper than MACE at €407.10. Flexible endoscope reprocessing cost €53.80. TNE was cheaper than oral endoscopy as sedation was not required. Oral endoscopies have a further rate of infectious complications, estimated to cost €16.20 per oral procedure in inpatient admissions. Oral and TNE equipment are more expensive to purchase and maintain than MACE costing €79 330 and €81 819, respectively compared with MACE at €15 420 per annum. However, capsule endoscopes cost significantly more per procedure at €369.00 than the consumables for flexible endoscopy (per oral €12.30, TNE €5.30).

Conclusions

TNE cost less to perform than conventional per oral endoscopy. The cost of capsule endoscopes will need to be reduced significantly if routine use is to be expected.

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.

First prospective European study for the feasibility and safety of magnetically controlled capsule endoscopy in gastric mucosal abnormalities

BACKGROUND

While capsule endoscopy (CE) is the gold standard diagnostic method of detecting small bowel (SB) diseases and disorders, a novel magnetically controlled capsule endoscopy (MCCE) system provides non-invasive evaluation of the gastric mucosal surface, which can be performed without sedation or discomfort. During standard SBCE, passive movement of the CE may cause areas of the complex anatomy of the gastric mucosa to remain unexplored, whereas the precision of MCCE capsule movements inside the stomach promises better visualization of the entire mucosa.

AIM

To evaluate the Ankon MCCE system’s feasibility, safety, and diagnostic yield in patients with gastric or SB disorders.

METHODS

Of outpatients who were referred for SBCE, 284 (male/female: 149/135) were prospectively enrolled and evaluated by MCCE. The stomach was examined in the supine, left, and right lateral decubitus positions without sedation. Next, all patients underwent a complete SBCE study protocol. The gastric mucosa was explored with the Ankon MCCE system with active magnetic control of the capsule endoscope in the stomach, applying three standardized pre-programmed computerized algorithms in combination with manual control of the magnetic movements.

RESULTS

The urea breath test revealed Helicobacter pylori positivity in 32.7% of patients. The mean gastric and SB transit times with MCCE were 0 h 47 min 40 s and 3 h 46 min 22 s, respectively. The average total time of upper gastrointestinal MCCE examination was 5 h 48 min 35 s. Active magnetic movement of the Ankon capsule through the pylorus was successful in 41.9% of patients. Overall diagnostic yield for detecting abnormalities in the stomach and SB was 81.9% (68.6% minor; 13.3% major pathologies); 25.8% of abnormalities were in the SB; 74.2% were in the stomach. The diagnostic yield for stomach/SB was 55.9%/12.7% for minor and 4.9%/8.4% for major pathologies.

CONCLUSION

MCCE is a feasible, safe diagnostic method for evaluating gastric mucosal lesions and is a promising non-invasive screening tool to decrease morbidity and mortality in upper gastro-intestinal diseases.

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.

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.

The Application of Magnetic-Controlled Capsule Gastroscopy in Patients Refusing C-EGD: A Single-Center 5-Year Observational Study

Background and Aims

Screening for gastric diseases in symptomatic outpatients with conventional esophagogastroduodenoscopy (C-EGD) is expensive and has poor compliance. We aimed to explore the efficiency and safety of magnetic-controlled capsule gastroscopy (MCCG) in symptomatic outpatients who refused C-EGD.

Methods

We performed a retrospective study of 76794 consecutive symptomatic outpatients from January 2014 to October 2019. A total of 2318 adults (F/M = 1064/1254) in the MCCG group who refused C-EGD were matched with adults in the C-EGD group using propensity-score matching (PSM). The detection rates of abnormalities were analyzed to explore the application of MCCG in symptomatic patients.

Results

Our study demonstrated a prevalence of gastric ulcers (GUs) in patients with functional dyspepsia- (FD-) like symptoms of 8.14%. The detection rate of esophagitis and Barrett's esophagus was higher in patients with typical gastroesophageal reflux disease (GERD) symptoms than in patients in the other four groups (P < 0.01). The detection rates of gastric ulcers in the five groups (abdominal pain, bloating, heartburn, follow-up, and bleeding) were significantly different (P = 0.015). The total detection rate of gastric ulcers in symptomatic patients was 9.7%. A total of 7 advanced carcinomas were detected by MCCG and confirmed by endoscopic or surgical biopsy. The advanced gastric cancer detection rate was not significantly different between the MCCG group and the C-EGD matched group in terms of nonhematemesis GI bleeding (2 vs. 2, P = 1.00). In addition, the overall focal lesion detection rate in the MCCG group was superior to that in the C-EGD matched group (224 vs. 184, P = 0.038). MCCG gained a clinically meaningful small bowel diagnostic yield of 54.8% (17/31) out of 31 cases of suspected small bowel bleeding. No patient reported capsule retention at the two-week follow-up.

Conclusion

MCCG is well tolerated, safe, and technically feasible and has a considerable diagnostic yield. The overall gastric diagnostic yield of gastric focal lesions with MCCG was comparable to that with C-EGD. MCCG offered a supplementary diagnosis in patients who had a previously undiagnostic C-EGD, indicating that MCCG could play an important role in the routine monitoring and follow-up of outpatient. MCCG shows its safety and efficiency in symptomatic outpatient applications.

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.

Screening for upper gastrointestinal cancers with magnetically controlled capsule gastroscopy: a feasibility study

BACKGROUND

The medical consortium is an intensive and disease-specific association that integrates tertiary public hospitals and medical examination centers in China. We aimed to evaluate the feasibility of the medical consortium for screening upper gastrointestinal (GI) cancers (MCSC) by magnetically controlled capsule gastroscopy (MCCG).

METHODS

6627 asymptomatic subjects underwent MCCG as part of health check-ups in the MCSC between March and November 2018. Relevant clinical data were collected and analyzed.

RESULTS

The MCSC detected 32 patients with upper GI cancer (0.48 %) confirmed by pathology. The detection rate of early gastric cancer was 16.67 % (4 /24). Gastric polyps, ulcers, and submucosal tumors were found in 15.54 %, 3.76 %, and 3.17 % of subjects, respectively. The whole GI preparation and operation process were well tolerated.

CONCLUSIONS

The MCSC was a feasible model for upper GI cancer screening, especially for asymptomatic subjects. Further prospective studies with better operational quality control are warranted.

Role of capsule endoscopy in inflammatory bowel disease: Anything new?

Capsule endoscopy (CE) is a recently developed diagnostic method for diseases of the small bowel that is non-invasive, safe, and highly tolerable. Its role in patients with inflammatory bowel disease has been widely validated in suspected and established Crohn’s disease (CD) due to its ability to assess superficial lesions not detected by cross-sectional imaging and proximal lesions of the small bowel not evaluable by ileocolonoscopy. Because CE is a highly sensitive but less specific technique, differential diagnoses that can simulate CD must be considered, and its interpretation should be supported by other clinical and laboratory indicators. The use of validated scoring systems to characterize and estimate lesion severity (Lewis score, Capsule Endoscopy Crohn’s Disease Activity Index), as well as the standardization of the language used to define the lesions (Delphi Consensus), have reduced the interobserver variability in CE reading observed in clinical practice, allowing for the optimization of diagnoses and clinical management strategies. The appearance of the panenteric CE, the incorporation of artificial intelligence, magnetically-guided capsules, and tissue biopsies are elements that contribute to CE being a promising, unique diagnostic tool in digestive tract diseases.

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.

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.

Capsule endoscopy - Recent developments and future directions

INTRODUCTION

Capsule endoscopy (CE) is an established modality in the diagnostic algorithm of small bowel (SB) pathology. Its use has expanded for investigation of upper and lower gastrointestinal diseases with similar prototypes.

AREAS COVERED

This review covers the role and recent advances of CE, as a non-invasive investigative tool.

EXPERT OPINION

The use of upper gastrointestinal CE is useful in patients who require surveillance for varices particularly in the current era of the COVID-19 pandemic. It has also shown high accuracy in the detection of upper gastrointestinal hemorrhage in patients presenting with a suspicion of hemorrhage. Findings on CE help to guide further management by device-assisted enteroscopy. The data on colon CE suggest comparable diagnostic accuracy to colonoscopy for polyp detection; however, more evidence is required in the high-risk group. Crohn's CE has become an integral part of the management of patients with Crohn's disease offering a comparative assessment tool post escalation of therapy. Artificial intelligence within CE has demonstrated similar if not better diagnostic yield compared to the human with a significantly shorter reading time. Artificial intelligence is likely to be in-built within CE reading platforms over the next few years minimizing reporting time and human error.

Neuroendocrine neoplasia of the gastrointestinal tract revisited: towards precision medicine

Over the past 5 years, a number of notable research advances have been made in the field of neuroendocrine cancer, specifically with regard to neuroendocrine cancer of the gastrointestinal tract. The aim of this Review is to provide an update on current knowledge that has proven effective for the clinical management of patients with these tumours. For example, for the first time in the tubular gastrointestinal tract, well-differentiated high-grade (grade 3) tumours and mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs) are defined in the WHO classification. This novel classification enables efficient identification of the most aggressive well-differentiated neuroendocrine tumours and helps in defining the degree of aggressiveness of MiNENs. The Review also discusses updates to epidemiology, cell biology (including vesicle-specific components) and the as-yet-unresolved complex genetic background that varies according to site and differentiation status. The Review summarizes novel diagnostic instruments, including molecules associated with the secretory machinery, novel radiological approaches (including pattern recognition techniques), novel PET tracers and liquid biopsy combined with DNA or RNA assays. Surgery remains the treatment mainstay; however, peptide receptor radionuclide therapy with novel radioligands and new emerging medical therapies (including vaccination and immunotherapy) are evolving and being tested in clinical trials, which are summarized and critically reviewed here.

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.

The Future of Capsule Endoscopy: The Role of Artificial Intelligence and Other Technical Advancements

Capsule endoscopy has revolutionized the management of small-bowel diseases owing to its convenience and noninvasiveness. Capsule endoscopy is a common method for the evaluation of obscure gastrointestinal bleeding, Crohn’s disease, small-bowel tumors, and polyposis syndrome. However, the laborious reading process, oversight of small-bowel lesions, and lack of locomotion are major obstacles to expanding its application. Along with recent advances in artificial intelligence, several studies have reported the promising performance of convolutional neural network systems for the diagnosis of various small-bowel lesions including erosion/ulcers, angioectasias, polyps, and bleeding lesions, which have reduced the time needed for capsule endoscopy interpretation. Furthermore, colon capsule endoscopy and capsule endoscopy locomotion driven by magnetic force have been investigated for clinical application, and various capsule endoscopy prototypes for active locomotion, biopsy, or therapeutic approaches have been introduced. In this review, we will discuss the recent advancements in artificial intelligence in the field of capsule endoscopy, as well as studies on other technological improvements in capsule endoscopy.

Prevalence of Gastric and Small-Intestinal Mucosal Injury in Elderly Patients Taking Enteric-Coated Aspirin by Magnetically Controlled Capsule Endoscopy

Objective

To investigate aspirin-related gastric and small-intestinal mucosal injury in elderly patients by magnetically controlled capsule endoscopy (MCCE).

Methods

Patients taking enteric-coated aspirin attending the outpatient department of Beijing Anzhen Hospital, Capital Medical University, from September 2017 to July 2019 underwent MCCE to assess injury to the gastric and small-intestinal mucosa. The patients were divided into the elderly group (age ≥ 60 years) and middle-aged group (45 years ≤ age < 60 years), and their clinical data were evaluated.

Results

Sixty-eight patients (34 per group) taking enteric-coated aspirin were recruited, and the elderly and middle-aged groups did not differ significantly in sex, history of smoking, history of alcohol consumption, body mass index, or accompanying diseases. In the elderly and middle-aged groups, the gastric Lanza scores were 2.0 (2.0, 3.0) and 2.0 (1.0, 3.0; P = 0.192), the numbers of patients with small-intestinal mucosal injuries (at least one erosion and/or ulcer) were 30 (88.2%) and 15 (44.1%; P < 0.001), the numbers of patients with more severe small-intestinal mucosal injuries (larger erosion and/or ulcer) were 11 (32.4%) and 3 (8.8%; P = 0.033), the numbers of patients with ileal erosion were 22 (64.7%) and 8 (23.5%; P = 0.001), and the durations of aspirin use were 30.0 (12.0, 120.0) and 10.5 (2.0–48.0) months (P = 0.007), respectively.

Conclusions

The rate of small-intestinal mucosal injury was significantly higher in elderly than in middle-aged patients taking enteric-coated aspirin, especially the rate of ileal erosion. MCCE enables the monitoring of aspirin-related gastric and small-intestinal mucosal injury in elderly patients, which can guide treatment decision making.

Magnetically assisted capsule endoscopy in suspected acute upper GI bleeding versus esophagogastroduodenoscopy in detecting focal lesions

BACKGROUND AND AIMS

Acute upper GI bleeding is common and requires investigation with EGD, but endotherapy is not always necessary. Magnetically assisted capsule endoscopy (MACE) uses a capsule steerable by an external magnet and allows examination of the upper GI tract and small bowel, but its role in acute upper GI bleeding has not been assessed.

METHODS

We conducted a prospective cohort study comparing the diagnostic yield of MACE and EGD in patients with suspected acute upper GI bleeding. Patient tolerance, mucosal visibility by MACE, and frequency of small-bowel bleeding were assessed. Whether or not MACE could safely predict discharge of patients was also determined.

RESULTS

Thirty-three patients were included for analysis (median age, 60 years; 75.8% male). MACE detected more focal lesions (peptic, vascular, and fresh/altered blood without a clear source) than EGD (40 versus 25, respectively, P = .02) but statistical significance was not reached for significant lesions (considered to be the bleeding source; 14 vs 13, respectively, P = 1). Capsule endoscopy identified an additional cause for bleeding in the small bowel in 18%. Visualization by MACE was excellent in most areas; views of the esophagus, gastroesophageal junction, fundus, and duodenal bulb were suboptimal. MACE was better tolerated than unsedated EGD and correctly identified patients who were safe for discharge.

CONCLUSIONS

MACE had higher diagnostic yield for focal lesions and was better tolerated than EGD. It also correctly predicted safe discharge for patients with acute upper GI bleeding. (Clinical trials registration number: NCT02690376.).

Miniature gastrointestinal endoscopy: Now and the future

Since its original application, gastrointestinal (GI) endoscopy has undergone many innovative transformations aimed at expanding the scope, safety, accuracy, acceptability and cost-effectiveness of this area of clinical practice. One method of achieving this has been to reduce the caliber of endoscopic devices. We propose the collective term “Miniature GI Endoscopy”. In this Opinion Review, the innovations in this field are explored and discussed. The progress and clinical use of the three main areas of miniature GI endoscopy (ultrathin endoscopy, wireless endoscopy and scanning fiber endoscopy) are described. The opportunities presented by these technologies are set out in a clinical context, as are their current limitations. Many of the positive aspects of miniature endoscopy are clear, in that smaller devices provide access to potentially all of the alimentary canal, while conferring high patient acceptability. This must be balanced with the costs of new technologies and recognition of device specific challenges. Perspectives on future application are also considered and the efforts being made to bring new innovations to a clinical platform are outlined. Current devices demonstrate that miniature GI endoscopy has a valuable place in investigation of symptoms, therapeutic intervention and screening. Newer technologies give promise that the potential for enhancing the investigation and management of GI complaints is significant.