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

Advances of surgical robotics: image-guided classification and application

Surgical robotics application in the field of minimally invasive surgery has developed rapidly and has been attracting increasingly more research attention in recent years. A common consensus has been reached that surgical procedures are to become less traumatic and with the implementation of more intelligence and higher autonomy, which is a serious challenge faced by the environmental sensing capabilities of robotic systems. One of the main sources of environmental information for robots are images, which are the basis of robot vision. In this review article, we divide clinical image into direct and indirect based on the object of information acquisition, and into continuous, intermittent continuous, and discontinuous according to the target-tracking frequency. The characteristics and applications of the existing surgical robots in each category are introduced based on these two dimensions. Our purpose in conducting this review was to analyze, summarize, and discuss the current evidence on the general rules on the application of image technologies for medical purposes. Our analysis gives insight and provides guidance conducive to the development of more advanced surgical robotics systems in the future.

Capsule endoscopy and panendoscopy: A journey to the future of gastrointestinal endoscopy

In 2000, the small bowel capsule revolutionized the management of patients with small bowel disorders. Currently, the technological development achieved by the new models of double-headed endoscopic capsules, as miniaturized devices to evaluate the small bowel and colon [pan-intestinal capsule endoscopy (PCE)], makes this non-invasive procedure a disruptive concept for the management of patients with digestive disorders. This technology is expected to identify which patients will require conventional invasive endoscopic procedures (colonoscopy or balloon-assisted enteroscopy), based on the lesions detected by the capsule, i.e., those with an indication for biopsies or endoscopic treatment. The use of PCE in patients with inflammatory bowel diseases, namely Crohn's disease, as well as in patients with iron deficiency anaemia and/or overt gastrointestinal (GI) bleeding, after a non-diagnostic upper endoscopy (esophagogastroduodenoscopy), enables an effective, safe and comfortable way to identify patients with relevant lesions, who should undergo subsequent invasive endoscopic procedures. The recent development of magnetically controlled capsule endoscopy to evaluate the upper GI tract, is a further step towards the possibility of an entirely non-invasive assessment of all the segments of the digestive tract, from mouth-to-anus, meeting the expectations of the early developers of capsule endoscopy.

Magnetically driven capsules with multimodal response and multifunctionality for biomedical applications

Untethered capsules hold clinical potential for the diagnosis and treatment of gastrointestinal diseases. Although considerable progress has been achieved recently in this field, the constraints imposed by the narrow spatial structure of the capsule and complex gastrointestinal tract environment cause many open-ended problems, such as poor active motion and limited medical functions. In this work, we describe the development of small-scale magnetically driven capsules with a distinct magnetic soft valve made of dual-layer ferromagnetic soft composite films. A core technological advancement achieved is the flexible opening and closing of the magnetic soft valve by using the competitive interactions between magnetic gradient force and magnetic torque, laying the foundation for the functional integration of both drug release and sampling. Meanwhile, we propose a magnetic actuation strategy based on multi-frequency response control and demonstrate that it can achieve effective decoupled regulation of the capsule's global motion and local responses. Finally, through a comprehensive approach encompassing ideal models, animal ex vivo models, and in vivo assessment, we demonstrate the versatility of the developed magnetic capsules and their multiple potential applications in the biomedical field, such as targeted drug delivery and sampling, selective dual-drug release, and light/thermal-assisted therapy.

Review article: Current status and future directions of ingestible electronic devices in gastroenterology

BACKGROUND

Advances in microelectronics have greatly expanded the capabilities and clinical potential of ingestible electronic devices.

AIM

To provide an overview of the structure and potential impact of ingestible devices in development that are relevant to the gastrointestinal tract.

METHODS

We performed a detailed literature search to inform this narrative review.

RESULTS

Technical success of ingestible electronic devices relies on the ability to miniaturise the microelectronic circuits, sensors and components for interventional functions while being sufficiently powered to fulfil the intended function. These devices offer the advantages of being convenient and minimally invasive, with real-time assessment often possible and with minimal interference to normal physiology. Safety has not been a limitation, but defining and controlling device location in the gastrointestinal tract remains challenging. The success of capsule endoscopy has buoyed enthusiasm for the concepts, but few ingestible devices have reached clinical practice to date, partly due to the novelty of the information they provide and also due to the challenges of adding this novel technology to established clinical paradigms. Nonetheless, with ongoing technological advancement and as understanding of their potential impact emerges, acceptance of such technology will grow. These devices have the capacity to provide unique insight into gastrointestinal physiology and pathophysiology. Interventional functions, such as sampling of tissue or luminal contents and delivery of therapies, may further enhance their ability to sharpen gastroenterological diagnoses, monitoring and treatment.

CONCLUSIONS

The development of miniaturised ingestible microelectronic-based devices offers exciting prospects for enhancing gastroenterological research and the delivery of personalised, point-of-care medicine.

The Future of Minimally Invasive Capsule Panendoscopy: Robotic Precision, Wireless Imaging and AI-Driven Insights

In the early 2000s, the introduction of single-camera wireless capsule endoscopy (CE) redefined small bowel study. Progress continued with the development of double-camera devices, first for the colon and rectum, and then, for panenteric assessment. Advancements continued with magnetic capsule endoscopy (MCE), particularly when assisted by a robotic arm, designed to enhance gastric evaluation. Indeed, as CE provides full visualization of the entire gastrointestinal (GI) tract, a minimally invasive capsule panendoscopy (CPE) could be a feasible alternative, despite its time-consuming nature and learning curve, assuming appropriate bowel cleansing has been carried out. Recent progress in artificial intelligence (AI), particularly in the development of convolutional neural networks (CNN) for CE auxiliary reading (detecting and diagnosing), may provide the missing link in fulfilling the goal of establishing the use of panendoscopy, although prospective studies are still needed to validate these models in actual clinical scenarios. Recent CE advancements will be discussed, focusing on the current evidence on CNN developments, and their real-life implementation potential and associated ethical challenges.

Patients at risk for further examination with conventional gastroscopy after undergoing magnetically controlled capsule endoscopy

OBJECTIVE

In this study we aimed to compare the need for further examination with conventional gastroscopy within 1 year after magnetically assisted capsule endoscopy (MCCE) examination between patients with gastrointestinal (GI) symptoms and asymptomatic individuals.

METHODS

After propensity score matching analysis, 372 patients with GI symptoms and 372 asymptomatic individuals who had undergone MCCE at the First Affiliated Hospital of Sun Yat-sen University from January 1, 2019 to December 30, 2020 were retrospectively enrolled. Demographic and clinical characteristics of the participants and their MCCE and gastroscopic findings (performed within 1 year after MCCE) were analyzed.

RESULTS

Fifty-one (6.85%) patients underwent further examination with conventional gastroscopy within 1 year after MCCE. Those with GI symptoms were more likely to undergo conventional gastroscopy than those without (9.95% vs 3.76%, P < 0.001). Polyps were the most common finding of MCCE. The rate of conventional gastroscopy in patients with focal lesions was significantly higher than that in those without focal lesions (P < 0.05). However, such rate did not differ in the different age groups (P = 0.106).

CONCLUSIONS

MCCE is an optimal alternative for gastric examination, especially for large-scale screening of asymptomatic individuals. Patients with GI symptoms or focal lesions detected by MCCE are more likely to seek further examination with conventional gastroscopy for biopsy or endoscopic treatment than those without.

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.

Small-sized versus standard magnetic capsule endoscopy in adults: a two-center, double-blinded randomized controlled trial

BACKGROUND : Certain patients experience difficulty swallowing a video capsule endoscopy (VCE) device owing to its relatively large size. The newly developed small-sized magnetically controlled capsule endoscopy (MCE) device is the smallest VCE device ever reported. We aimed to evaluate the performance of the small-sized MCE device in terms of ingestion and examination efficacy. METHODS : Patients in two centers were prospectively enrolled and randomized to the small-sized or standard MCE groups. Differences in capsule ingestion difficulties, visualization of the gastrointestinal tract, and capsule transit times were compared. RESULTS : 96 patients were enrolled (48 in each group). In the small-sized MCE group, the mean (SD) difficulty score and time to swallow the capsule, and success rate for swallowing the capsule at the first attempt were 0.6 (1.0), 3.4 (1.3) seconds, and 89.6 %, which was significant better compared with the standard MCE group with 3.1 (1.7), 12.0 (14.3) seconds and 60.4 %, respectively (all P < 0.001). Visualization of the esophagus, stomach, and small bowel were comparable between the two groups. The small-sized MCE group had a significantly shorter gastric transit time (49.4 minutes vs. 66.2 minutes; P = 0.04) and longer small-bowel transit time (5.8 hours vs. 5.0 hours; P = 0.045). CONCLUSIONS : The small-sized MCE device is feasible and safe for gastrointestinal examination, alleviating difficulties in capsule ingestion, improving gastric emptying under magnetic control, and prolonging the small-bowel transit time.

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.

In vitro and in vivo evaluation of a novel wired transmission magnetically controlled capsule endoscopy system for upper gastrointestinal examination

BACKGROUND

Magnetically controlled capsule endoscopy (MCCE) has recently increasingly been used for gastric examination. However, the image quality and esophageal observation is suboptimal. We developed a novel wired transmission magnetically controlled capsule endoscopy (WT-MCCE) system and evaluated its feasibility through in vitro and in vivo experiments.

METHODS

A plastic stomach model and a pathological upper gastrointestinal model were used to evaluate the performance of WT-MCCE in vitro experiments. Twice of examination in the two in vitro models by WT-MCCE were performed by 5 endoscopists who were experienced in performing wireless capsule endoscopy. The examination of traditional gastroscopy (Olympus, GIF-HQ290) in the pathological upper gastrointestinal model was set as the control. In vivo experiments were performed in a live canine model by 3 endoscopists, in which WT-MCCE was inserted with the assistance of gastroscopy. Measurements included maneuverability, examination time, visualization of gastric mucosa, image quality and diagnostic accuracy.

RESULTS

WT-MCCE showed good performance in both in vitro and in vivo experiments with excellent visualization of mucosa (75-100%). The mean operation time is 17.6 ± 2.7 min, 22.3 ± 1.9 min and 29.3 ± 3.4 min in three models, respectively. In pathological upper gastrointestinal model, all lesions, including esophageal varices, one polyp, one foreign body, two gastric ulcers and one duodenal ulcer, were detected by both WT-MCCE and traditional gastroscopy by all endoscopists. For the observation of esophagus and stomach in the canine model, WT-MCCE also showed excellent maneuverability and good image quality.

CONCLUSIONS

The novel WT-MCCE system performed well in evaluating upper gastrointestinal landmarks and lesions in two in vitro models, and showed good performance in a canine model. WT-MCCE may be potentially useful for diagnosis of esophageal and gastric diseases.

Feasibility of Novel Magnetically Controlled Cable Capsule Endoscopy System In Vitro Experiments for Gastric Examination

Background

Magnetically controlled capsule endoscopy has been shown to be feasible for the examination of gastric diseases. However, there may be problems, such as low image quality, incomplete esophageal observation, and capsule retention. We developed a novel magnetically controlled cable capsule endoscopy (MCCCE) system and evaluated its feasibility through in vitro experiments.

Methods

Three experienced endoscopists performed MCCCE on the plastic stomach model and the excised porcine stomach model 5 times, respectively. Outcomes included handle ability, examination time, examination completion, and image quality. The examination completion was accessed by other two blinded endoscopists, and the image quality was compared with conventional gastroscopy (Olympus, GIF-290).

Results

The performance of MCCCE in vitro experiments is excellent, with a mean operation time of 18.5 minutes in the plastic stomach model and 17.3 minutes in the excised porcine stomach model. The visualization rate of the gastric mucosa is >90% in the plastic stomach model and 75–90% in the excised porcine stomach model. The images of MCCCE are very clear, with good color resolution and no image distortion, which seem to be comparable to conventional gastroscopy.

Conclusions

MCCCE system is feasible for gastric examination in vitro experiments, living animal experiments and human trials need to be further conducted.

Endoscopic methods for the detection and treatment of gastric cancer

PURPOSE OF REVIEW

The intent of this review is to describe new advances in endoscopic approaches to surveillance and management of gastric cancer.

RECENT FINDINGS

There are new endoscopic techniques and approaches that have improved the detection of gastric cancer, including narrow band imaging, confocal laser endocytomicroscopy and magnetically controlled capsule endoscopy. This article highlights the role of endoscopic submucosal dissection in the treatment of focal and diffuse gastric dysplasia and early gastric cancer with a discussion of indications, complications and outcomes. We review several recent guidelines addressing the surveillance strategies for individuals at high-risk for developing gastric cancer, such as those with atrophic gastritis and intestinal metaplasia, how gastric dysplasia and early gastric cancer can be endoscopically managed, and recommended surveillance after endoscopic intervention.

SUMMARY

Endoscopic approaches are evolving rapidly that will improve detection of dysplasia and early gastric cancer in high-risk individuals. Surveillance guidelines from various international societies reflect differences in local experience and prevalence of gastric cancer. Endoscopic submucosal dissection is now widely accepted as a first-line approach to early gastric cancers that can be resected en-bloc .

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.

Risk stratification with video capsule endoscopy leads to fewer hospital admissions in emergency department patients with low-risk to moderate-risk upper gastrointestinal bleed: A multicenter clinical trial

OBJECTIVE

In US emergency departments (EDs), the physician has limited ability to evaluate for common and serious conditions of the gastrointestinal (GI) mucosa such as a bleeding peptic ulcer. Although many bleeding lesions are self-limited, the majority of these patients require emergency hospitalization for upper endoscopy (EGD). We conducted a clinical trial to determine if ED risk stratification with video capsule endoscopy (VCE) reduces hospitalization rates for low-risk to moderate-risk patients with suspected upper GI bleeding.

METHODS

We conducted a randomized controlled trial at 3 urban academic EDs. Inclusion criteria included signs of upper GI bleeding and a Glasgow Blatchford score <6. Patients were randomly assigned to 1 of the following 2 treatment arms: (1) an experimental arm that included VCE risk stratification and brief ED observation versus (2) a standard care arm that included admission for inpatient EGD. The primary outcome was hospital admission. Patients were followed for 7 and 30 days to assess for rebleeding events and revisits to the hospital.

RESULTS

The trial was terminated early as a result of low accrual. The trial was also terminated early because of a need to repurpose all staff to respond to the coronavirus disease 2019 pandemic. A total of 24 patients were enrolled in the study. In the experimental group, 2/11 (18.2%) patients were admitted to the hospital, and in the standard of care group, 10/13 (76.9%) patients were admitted to the hospital (P = 0.012). There was no difference in safety on day 7 and day 30 after the index ED visit.

CONCLUSIONS

VCE is a potential strategy to decrease admissions for upper GI bleeding, though further study with a larger cohort is required before this approach can be recommended.

Fully automated magnetically controlled capsule endoscopy for examination of the stomach and small bowel: a prospective, feasibility, two-centre study

BACKGROUND

The use of magnetically controlled capsules for gastroscopy is in the early stages of clinical adoption. We aimed to evaluate the safety and efficacy of a fully automated magnetically controlled capsule endoscopy (FAMCE) system in clinical practice for gastroscopy and small bowel examination.

METHODS

We did a prospective, comparative study to evaluate the safety and efficacy of FAMCE. Patients from two hospitals in Chongqing, China were consecutively enrolled. Eligible participants were aged 18-80 years with suspected gastric pathology and no previous surgery. Participants underwent FAMCE for screening of gastric lesions, then conventional transoral gastroscopy 2 h later, and stomach examination results were compared. The primary outcome was the rate of complete detection of gastric anatomy landmarks (cardia, fundus, body, angulus, antrum, and pylorus) by FAMCE. Secondary outcomes were the time required for gastric completion by FAMCE, the rate of detection of gastric lesions by FAMCE compared with conventional transoral gastroscopy, and the rate of complete small bowel examination. Adverse events were also evaluated. The study was registered in the Chinese Clinical Trial Registry, ChiCTR2000040507.

FINDINGS

Between May 12 and Aug 17, 2020, 114 patients (mean age 44·0 years [IQR 34·0-55·0]; 63 [55%] female) were enrolled. The rate of complete detection of gastric anatomical structures by FAMCE was 100% (95% CI 99·3-100·0). The concordance between FAMCE and conventional transoral gastroscopy was 99·61% (99·45-99·78). The mean completion time of a gastroscopy with FAMCE was 19·17 min (SD 1·43; median 19·00, IQR 19·00-20·00), compared with 5·21 min (2·00; 5·18, 3·68-6·45) for conventional transoral gastroscopy. In 114 enrolled patients, 214 lesions were detected by FAMCE and conventional transoral gastroscopy. Of those, 193 were detected by both modalities. FAMCE missed five pathologies (four cases of gastritis and one polyp), whereas conventional transoral gastroscopy missed 16 pathologies (12 cases of gastritis, one polyp, one fundal xanthoma, and two antral erosions). FAMCE was able to provide a complete small bowel examination for all 114 patients and detected intestinal lesions in 50 (44%) patients. During the study, two (2%) patients experienced adverse events. No serious adverse events were recorded, and there was no evidence of capsule retention.

INTERPRETATION

The performance of FAMCE is similar to conventional transoral gastroscopy in completion of gastric examination and lesion detection. Furthermore, it can provide a complete small bowel examination. Therefore, FAMCE could be effective method for examination of the gastrointestinal tract.

FUNDING

Chinese National Key Research and Development Program.

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.

Autophagy in Gastric Mucosa: The Dual Role and Potential Therapeutic Target

The incidence of stomach diseases is very high, which has a significant impact on human health. Damaged gastric mucosa is more vulnerable to injury, leading to bleeding and perforation, which eventually aggravates the primary disease. Therefore, the protection of gastric mucosa is crucial. However, existing drugs that protect gastric mucosa can cause nonnegligible side effects, such as hepatic inflammation, nephritis, hypoacidity, impotence, osteoporotic bone fracture, and hypergastrinemia. Autophagy, as a major intracellular lysosome-dependent degradation process, plays a key role in maintaining intracellular homeostasis and resisting environmental pressure, which may be a potential therapeutic target for protecting gastric mucosa. Recent studies have demonstrated that autophagy played a dual role when gastric mucosa exposed to biological and chemical factors. More indepth studies are needed on the protective effect of autophagy in gastric mucosa. In this review, we focus on the mechanisms and the dual role of various biological and chemical factors regulating autophagy, such as Helicobacter pylori, virus, and nonsteroidal anti-inflammatory drugs. And we summarize the pathophysiological properties and pharmacological strategies for the protection of gastric mucosa through autophagy.

Screening value for gastrointestinal lesions of magnetic-controlled capsule endoscopy in asymptomatic individuals

BACKGROUND AND AIM

Most patients with gastric tumors and precancerous lesions are asymptomatic, which often results in delayed diagnosis and treatment. Compared with conventional gastroscopy and capsule endoscopy, magnetic-controlled capsule endoscopy is a non-invasive, effective, and cost-efficient diagnostic modality for gastric examination. We retrospectively investigated magnetic-controlled capsule endoscopy as a screening tool for gastrointestinal lesions (particularly gastric tumors and precancerous lesions) in asymptomatic individuals.

METHODS

In this retrospective study, 1757 patients who voluntarily underwent magnetic-controlled capsule endoscopy between January and December 2019 at nine medical centers across Shaanxi province based on strict inclusion and exclusion criteria were enrolled. The primary outcomes were gastric tumor and precancerous lesion detection rates and procedural safety.

RESULTS

The upper and lower gastrointestinal lesion detection rates were 98.35% (1728/1757) and 21.61% (78/361), respectively; 2.28% of patients were diagnosed with gastric tumors including gastric cancer (4/1757) and submucosal tumors (36/1757). Three types of precancerous lesions were found in 591 patients (33.64%), including chronic atrophic gastritis (23.16%), gastric polyp (10.98%), and gastric ulcer (2.96%). For patients aged over 40 years, the detection rate of precancerous lesions was higher (14.36% vs 42.58%, P < 0.001). No patient was diagnosed with small intestinal cancer. No adverse events occurred.

CONCLUSIONS

Magnetic-controlled capsule endoscopy could be used as a promising novel screening modality for diagnosis of gastrointestinal lesions in asymptomatic individuals, specifically gastric tumors and precancerous lesions, with the advantages of safety, non-invasiveness, effectiveness, and cost-efficiency.

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.

Screening for gastric cancer in China: Advances, challenges and visions

Gastric cancer (GC) is one of the major cancers in China and all over the world. Most GCs are diagnosed at an advanced stage with unfavorable prognosis. Along with some other countries, China has developed the government-funded national screening programs for GC and other major cancers. GC screening has been shown to effectively decrease the incidence of and mortality from GC in countries adopting nationwide screening programs (Japan and Korea) and in studies based on selected Chinese populations. The screening of GC relies mostly on gastroendoscopy, the accuracy, reliability and safety of which have been indicated by previous studies. However, considering its invasive screening approach, requirements on skilled endoscopists and pathologists, and a high cost, developing noninvasive methods to amend endoscopic screening would be highly needed. Numerous studies have examined biomarkers for GC screening and the combination of biomarkers involving pepsinogen, gastrin, and Helicobacter pylori antibodies has been proposed for risk stratification, seeking to narrow down the high-risk populations for further endoscopy. Despite all the achievements of endoscopic screening, evidence on appropriate screening age, intervals for repeated screening, novel biomarkers promoting precision prevention, and health economics need to be accumulated to inform policymakers on endoscopic screening in China. With the guide of Health China 2030 Planning Outline, we have golden opportunities to promote prevention and control of GC. In this review, we summarize the characteristics of screening programs in China and other East Asian countries and introduce the past and current approaches and strategies for GC screening, aiming for featuring the latest advances and key challenges, and illustrating future visions of GC screening.

Elevated Levels of Oxidative Nucleic Acid Modification Markers in Urine From Gastric Cancer Patients: Quantitative Analysis by Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry

Oxidative nucleic acid modifications have attracted increasing attention in recent years since they have been found to be related to a number of diseases including cancer. 8-Hydroxy-2'-deoxyguanosine (8-OHdG) and 8-hydroxyguanosine (8-OHG) are the typical markers of oxidative modification of DNA and RNA, respectively, and they are emerging biomarkers for the early detection of diseases. Urine is a favored biofluid for biomarker discovery due to its noninvasiveness to patients. Accurate quantification of these oxidative nucleic acid modifications still has challenges because their amounts in urine are very low and the interferences in urine samples are complicated. Herein, we developed and validated an accurate and robust solid-phase extraction (SPE) coupled with ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the simultaneous quantification of these oxidative nucleic acid modifications in human urine. Stable isotope dilution strategy was utilized and the method shows good precision on intraday and interday measurements. Meanwhile, recovery was satisfactory by utilizing the Oasis hydrophilic-lipophilic balance (HLB) cartridge for sample pretreatment at three spiked levels. We successfully quantified urinary 8-OHdG and 8-OHG from 60 gastric cancer patients and 70 healthy controls by using this method. The measured contents of 8-OHdG and 8-OHG in urine from gastric cancer patients are both increased, compared with those in urine from healthy controls, indicating these oxidative nucleic acid modifications could act as potential non-invasive markers for early diagnosis of gastric cancer. Moreover, the present study will stimulate investigations of the effects of oxidative stress and nucleic acid modifications on the initiation and progression of gastric cancer.

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.).

Video capsule endoscopy for upper gastrointestinal hemorrhage in the emergency department: A systematic review and meta-analysis

OBJECTIVE

The assessment of the severity of upper gastrointestinal hemorrhage in emergency department (ED) patients is difficult to assess with commonly available diagnostic tools. Small studies have shown that video capsule endoscopy (VCE) is a promising risk-stratification method and may be better than current clinical decision rules such as the Rockall score and the Glasgow Blatchford score. This review aims to assess the accuracy of VCE to detect active upper gastrointestinal hemorrhage compared to a reference standard.

METHODS

The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) methodology was used to perform a review of studies that have measured the diagnostic accuracy of VCE. Studies were included if they measured ED use of VCE for upper GI hemorrhage as compared to a reference standard of an esophagogastroduodenoscopy (EGD). A meta-analysis was performed on select patients using a fixed effects and random-effects model to determine the primary outcome of diagnostic test accuracy.

RESULTS

40 studies were screened for eligibility and five studies representing 193 patients met the inclusion and exclusion criteria. All patients received both a VCE and an EGD. The sensitivity and specificity of VCE were 0.724 and 0.748, respectively. The diagnostic odds ratio was 6.29 (95% CI: 3.23-12.25) and the summary receiver operating characteristic curve was 0.782.

CONCLUSIONS

VCE demonstrated high accuracy for detecting upper GI hemorrhage in this meta-analysis of existing studies. In light of the potential advantages of VCE in the ED, further research is warranted to further establish its role.

Comprehensive analysis of miRNA-gene regulatory network with clinical significance in human cancers

microRNAs (miRNAs), particularly the exosomal miRNAs have been widely used as biomarkers and promising therapeutic targets in cancer. However, a comprehensive analysis of miRNA-gene regulatory network with clinical significance remains scarce. The emergence of high-throughput multi-omics data over large, well-characterized patient cohorts provides an unprecedented opportunity to address this problem. Herein, we performed a clinic-centered analysis to identify cancer-associated miRNAs, miRNA-target axis. We first calculated the correlation among miRNA, mRNA and 75 unique clinico-pathological characteristics (CPCs) in 26 cancer types, and established an online resource (4CR). Interestingly, we found that the high expression of several DNA methylation-related enzymes was associated with adverse outcomes of cancer patients, and these genes were regulated by a cluster of miRNAs. Furthermore, by integrating exosomal miRNA and mRNA databases, we identified exosomal miRNA biomarkers for non-invasive cancer surveillance and therapy monitoring. Finally, we explored the role of CPC-related miRNAs for therapeutic effect prediction of drugs based on their shared targets. Our analysis pipeline illustrated the significance of clinic-centered analysis in miRNA-gene pair identification and provided helpful clues for future cancer studies.

Development of a Capsule Robot for Exploring the Colon

A tether-less inchworm-like capsule robot (ILCR) is promising to enable a non-invasive exploration of the colon, while existing ILCRs show barely satisfactory movement performance because the colon environment is nonstructural. In this current study, we develop an enhanced ILCR based on a design rule of maximizing the achievable periodic stroke and minimizing the body length, with the aim of improving movement performance. By designing an axial compact expanding mechanism (EM), employing a novel linear mechanism (LM), and integrating a hollow-cylinder-like power source based on wireless power transmission (WPT), the enhanced ILCR achieves a periodic stroke of 38 mm within a small body length of 33 mm. Our experiments show that the EM and LM can work reliably in an ex-vivo colon with a lot of intestinal mucus, and the power source can safely supply a stable working voltage of 3.3 V even in the worst case. Being wirelessly controlled and powered, the enhanced ILCR shows satisfactory movement performance, with velocities of 15.8 cm/min, 12.1 cm/min, and 7.4 cm/min in a transparent tube, a tiled colon, and a suspended colon, respectively, promising to accomplish an exploration for the 1.5-m long colon within 30 min.