Capsule endoscopy in patients refusing conventional endoscopy

An ingestible near-infrared fluorescence capsule endoscopy for specific gastrointestinal diagnoses

Early diagnosis of gastrointestinal (GI) diseases is important to effectively prevent carcinogenesis. Capsule endoscopy (CE) can address the pain caused by wired endoscopy in GI diagnosis. However, existing CE approaches have difficulty effectively diagnosing lesions that do not exhibit obvious morphological changes. In addition, the current CE cannot achieve wireless energy supply and attitude control at the same time. Here, we successfully developed a novel near-infrared fluorescence capsule endoscopy (NIFCE) that can stimulate and capture near-infrared (NIR) fluorescence images to specifically identify subtle mucosal microlesions and submucosal lesions while capturing conventional white light (WL) images to detect lesions with significant morphological changes. Furthermore, we constructed the first synergetic system that simultaneously enables multi-attitude control in NIFCE and supplies long-term power, thus addressing the issue of excessive power consumption caused by the NIFCE emitting near-infrared light (NIRL). We performed in vivo experiments to verify that the NIFCE can specifically "light up" tumors while sparing normal tissues by synergizing with probes actively aggregated in tumors, thus realizing specific detection and penetration. The prototype NIFCE system represents a significant step forward in the field of CE and shows great potential in efficiently achieving early targeted diagnosis of various GI diseases.

Study on the Characteristics of Traditional Chinese Medicine Syndromes in Patients with Erosive Gastritis Based on Metabolomics

According to traditional Chinese medicine theory, tongue coatings reflect changes in the body. The goal of this study was to identify a metabolite or a set of metabolites capable of classifying characteristics of traditional Chinese medicine syndromes in erosive gastritis. In this study, we collected tongue coatings of patients with erosive gastritis with damp-heat syndrome (DHS), liver depression and qi stagnation syndrome (LDQSS), and healthy volunteers. Then, we analyzed the differences in metabolic characteristics between the two groups based on metabolomics. We identified 14 potential biomarkers related to the DHS group, and six metabolic pathways were enriched. The differential pathways included pyrimidine metabolism, pantothenate and CoA biosynthesis, citrate cycle (TCA cycle), pyruvate metabolism, glycolysis/gluconeogenesis, and purine metabolism. Similarly, in the LDQSS group, we identified 25 potential biomarkers and 18 metabolic pathways were enriched. The top five pathways were the TCA cycle, sphingolipid metabolism, fatty acid biosynthesis, pantothenate and CoA biosynthesis, and the pentose phosphate pathway. In conclusion, the DHS group and the LDQSS group have different characteristics.

Psychosocial Predictors of Colorectal Cancer Screening Intention: An Experiment on the Invitation Letter

BACKGROUND

In Italy, attendance rates for colorectal cancer (CRC) screening are suboptimal. The present work analysed cognitive and emotional predictors of CRC screening intention and tested an intervention on a real invitation letter to improve CRC screening intention, both directly and in interaction with the predictors of our model.

METHODS

Our model included variables from the theory of planned behaviour and the emotional barriers to bowel screening scale. We applied six changes to an invitation letter used in Italy to avoid the repetition of words like 'faeces', 'blood', or 'occult' and reduce the prompting of disgust. The 228 participants were randomly assigned to a between-participants design (original letter vs. manipulated letter).

RESULTS

Disgust hindered CRC screening intention, while embarrassment, fear, and subjective norms (i.e., perception of the social pressures to attend CRC screening) were not associated with intention to screen. More positive attitudes towards CRC screening were associated with a higher intention to screen. The positive association between perceived behavioural control and CRC screening intention was stronger for participants who read the letter with fewer (vs. more) references to bodily waste. Letter manipulation did not affect intention to screen.

CONCLUSIONS

The disgust associated with faecal matter is a critical factor in determining CRC screening attendance, and it should be acknowledged as such in public policies. Until new screening tests avoiding the activation of this emotional reaction are concretely available, public campaigns should improve CRC screening participation by boosting both positive attitudes towards screening and patients' perceived behavioural control.

A review on model-based and model-free approaches to control soft actuators and their potentials in colonoscopy

Colorectal cancer (CRC) is the third most common cancer worldwide and responsible for approximately 1 million deaths annually. Early screening is essential to increase the chances of survival, and it can also reduce the cost of treatments for healthcare centres. Colonoscopy is the gold standard for CRC screening and treatment, but it has several drawbacks, including difficulty in manoeuvring the device, patient discomfort, and high cost. Soft endorobots, small and compliant devices thatcan reduce the force exerted on the colonic wall, offer a potential solution to these issues. However, controlling these soft robots is challenging due to their deformable materials and the limitations of mathematical models. In this Review, we discuss model-free and model-based approaches for controlling soft robots that can potentially be applied to endorobots for colonoscopy. We highlight the importance of selecting appropriate control methods based on various parameters, such as sensor and actuator solutions. This review aims to contribute to the development of smart control strategies for soft endorobots that can enhance the effectiveness and safety of robotics in colonoscopy. These strategies can be defined based on the available information about the robot and surrounding environment, control demands, mechanical design impact and characterization data based on calibration.

Evaluating clinical diversity and plausibility of synthetic capsule endoscopic images

Wireless Capsule Endoscopy (WCE) is being increasingly used as an alternative imaging modality for complete and non-invasive screening of the gastrointestinal tract. Although this is advantageous in reducing unnecessary hospital admissions, it also demands that a WCE diagnostic protocol be in place so larger populations can be effectively screened. This calls for training and education protocols attuned specifically to this modality. Like training in other modalities such as traditional endoscopy, CT, MRI, etc., a WCE training protocol would require an atlas comprising of a large corpora of images that show vivid descriptions of pathologies, ideally observed over a period of time. Since such comprehensive atlases are presently lacking in WCE, in this work, we propose a deep learning method for utilizing already available studies across different institutions for the creation of a realistic WCE atlas using StyleGAN. We identify clinically relevant attributes in WCE such that synthetic images can be generated with selected attributes on cue. Beyond this, we also simulate several disease progression scenarios. The generated images are evaluated for realism and plausibility through three subjective online experiments with the participation of eight gastroenterology experts from three geographical locations and a variety of years of experience. The results from the experiments indicate that the images are highly realistic and the disease scenarios plausible. The images comprising the atlas are available publicly for use in training applications as well as supplementing real datasets for deep learning.

Bioelectronic devices for light-based diagnostics and therapies

Light has broad applications in medicine as a tool for diagnosis and therapy. Recent advances in optical technology and bioelectronics have opened opportunities for wearable, ingestible, and implantable devices that use light to continuously monitor health and precisely treat diseases. In this review, we discuss recent progress in the development and application of light-based bioelectronic devices. We summarize the key features of the technologies underlying these devices, including light sources, light detectors, energy storage and harvesting, and wireless power and communications. We investigate the current state of bioelectronic devices for the continuous measurement of health and on-demand delivery of therapy. Finally, we highlight major challenges and opportunities associated with light-based bioelectronic devices and discuss their promise for enabling digital forms of health care.

The role of disgust as an emotional barrier to colorectal cancer screening participation: a systematic review and meta-analysis

OBJECTIVE

Worldwide colorectal cancer (CRC) screening rates are suboptimal. This systematic review and meta-analysis examine the role of disgust in CRC screening avoidance.

DESIGN

A systematic literature search was conducted. In all, 46 studies were included in the review. Among these, 16 studies were compared with a meta-analytical approach in order to 1) estimate the effect size of state disgust on screening intention and attendance; 2) examine whether methodological characteristics moderate the effect of state disgust on screening behaviour; 3) estimate the effect sizes of trait disgust and type of exam kit on state disgust.

RESULTS

In the reviewed studies, state disgust was often associated with CRC screening and especially with CRC screening avoidance. The meta-analysis confirmed low-to-moderate negative effects of state disgust on screening intention and attendance. Population sampling strategy was the only significant moderator of the effect of state disgust on screening attendance, i.e. studies that used convenience (versus random/representative) samples found a significantly lower effect size. Trait disgust and type of exam kit exerted a large and a moderate-to-large positive effect, respectively, on state disgust.

CONCLUSIONS

Disgust can boost CRC screening avoidance. Further studies and interventions must be designed to help patients in overcoming this emotional barrier.

Soft hybrid intrinsically motile robot for wireless small bowel enteroscopy

BACKGROUND

Difficulties in establishing diagnosis of small bowel (SB) disorders, prevented their effective treatment. This problem was largely resolved by wireless capsule endoscopy (WCE), which has since become the first line investigation for suspected SB disorders. Several types of WCE pills are now used in clinical practice, despite their limitations and complications. WCE pills are large, rigid and immotile capsules. When swallowed, they provide SB enteroscopy downloaded to a data logger carried by the patient. Most of the complications of WCEs result from lack of intrinsic locomotion: incomplete examination, capsule retention and impaction within strictures. In addition, the rigid nature and size of current generation of WCE pills is accompanied by 0.1% inability to swallow the pill by patients with normal esophageal motility.

METHODS

The aim of this communication is to describe the initial prototype, P1, which is thinner and slightly longer than the current generation of WCEs. In addition, it exhibits intrinsic active locomotion, produced by vibrating silicon legs. These generate a controlled-skid locomotion on the small bowel mucosal surface, rendered slippery by surface mucus and intraluminal surfactant bile salts. We demonstrate the mechanism responsible for the active locomotion of P1, which we consider translatable into a working prototype, suitable for further R&D for eventual clinical translation.

RESULTS

The shape and attachment of the rubber vibrating legs to vibrating actuators, have been designed specifically to produce a tight clockwise circular motion. When inserted inside a circular tube in vitro of equivalent diameter to human small intestine, the intrinsic circular clockwise motion of P1 translates into a linear locomotion by the constraints imposed by the surrounding circular walls of SB and rest of the gastrointestinal tract. This design ensures device stability during transit, essential for imaging and targeting lesions encountered during the enteroscopy. We preformed two experiments: (i) transit of P1 through a phantom consisting of a segment of PVC tube placed on a horizontal surface and (ii) transit through a transparent slippery nylon sleeve insufflated with air. In the PVC tube, its transit rate averages 15.6 mm/s, which is too fast for endoscopy: whereas inside the very slippery nylon sleeve insufflated with air, the average transit rate of P1 is reduced to 5.9 mm/s, i.e., ideal for inspection endoscopy.

CONCLUSIONS

These in-vitro experiments indicate that the P1 hybrid soft robot prototype has the potential specifically for clinical translation for SB enteroscopy.

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.

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.

Colon capsule endoscopy

There are multiple indications for luminal imaging of the colon. From assessment of known disease, to diagnosing new pathology; intra-luminal visualisation is the mainstay of gastrointestinal diagnosis. Colonoscopy and radiological imaging are currently the most frequently deployed diagnostic methods. However, both have an associated risk profile, have significant resource pressures and are not universally tolerated. Colon capsule endoscopy (CCE) offers an adjunct to these diagnostic options. In this narrative review the utility of CCE is described. Its current uses, potential benefits and future developments are also discussed.

Gastrointestinal diagnosis using non-white light imaging capsule endoscopy

Capsule endoscopy (CE) has proved to be a powerful tool in the diagnosis and management of small bowel disorders since its introduction in 2001. However, white light imaging (WLI) is the principal technology used in clinical CE at present, and therefore, CE is limited to mucosal inspection, with diagnosis remaining reliant on visible manifestations of disease. The introduction of WLI CE has motivated a wide range of research to improve its diagnostic capabilities through integration with other sensing modalities. These developments have the potential to overcome the limitations of WLI through enhanced detection of subtle mucosal microlesions and submucosal and/or transmural pathology, providing novel diagnostic avenues. Other research aims to utilize a range of sensors to measure physiological parameters or to discover new biomarkers to improve the sensitivity, specificity and thus the clinical utility of CE. This multidisciplinary Review summarizes research into non-WLI CE devices by organizing them into a taxonomic structure on the basis of their sensing modality. The potential of these capsules to realize clinically useful virtual biopsy and computer-aided diagnosis (CADx) is also reported.

Animal experimental studies using small intestine endoscope

AIM

To assess the feasibility and safety of a novel enteroscope, negative-pressure suction endoscope in examining the small intestine of a porcine model.

METHODS

In vitro experiments in small intestinal loops from 20 pigs and in vivo experiments in 20 living pigs were conducted.

RESULTS

In in vitro experiments, a negative pressure of > 0.06 MPa was necessary for optimal visualization of the intestine, and this pressure did not cause gross or histological damage to the mucosa. For satisfactory examination of the small intestine in vivo, higher negative pressure (> 1.00 MPa) was required. Despite this higher pressure, the small intestine did not show any gross or microscopic damage in the suctioned areas. The average time of examination in the living animals was 60 ± 7.67 min. The animals did not experience any apparent ill effects from the procedure.

CONCLUSION

Small intestine endoscope was safely performed within a reasonable time period and enabled complete visualization of the intestine in most cases.

A Predictive Model to Estimate Cost Savings of a Novel Diagnostic Blood Panel for Diagnosis of Diarrhea-predominant Irritable Bowel Syndrome

PURPOSE

A high incidence of irritable bowel syndrome (IBS) is associated with significant medical costs. Diarrhea-predominant IBS (IBS-D) is diagnosed on the basis of clinical presentation and diagnostic test results and procedures that exclude other conditions. This study was conducted to estimate the potential cost savings of a novel IBS diagnostic blood panel that tests for the presence of antibodies to cytolethal distending toxin B and anti-vinculin associated with IBS-D.

METHODS

A cost-minimization (CM) decision tree model was used to compare the costs of a novel IBS diagnostic blood panel pathway versus an exclusionary diagnostic pathway (ie, standard of care). The probability that patients proceed to treatment was modeled as a function of sensitivity, specificity, and likelihood ratios of the individual biomarker tests. One-way sensitivity analyses were performed for key variables, and a break-even analysis was performed for the pretest probability of IBS-D. Budget impact analysis of the CM model was extrapolated to a health plan with 1 million covered lives.

FINDINGS

The CM model (base-case) predicted $509 cost savings for the novel IBS diagnostic blood panel versus the exclusionary diagnostic pathway because of the avoidance of downstream testing (eg, colonoscopy, computed tomography scans). Sensitivity analysis indicated that an increase in both positive likelihood ratios modestly increased cost savings. Break-even analysis estimated that the pretest probability of disease would be 0.451 to attain cost neutrality. The budget impact analysis predicted a cost savings of $3,634,006 ($0.30 per member per month).

IMPLICATIONS

The novel IBS diagnostic blood panel may yield significant cost savings by allowing patients to proceed to treatment earlier, thereby avoiding unnecessary testing.

Capsule endoscopy: The road ahead

Since its introduction into clinical practice 15 years ago, capsule endoscopy (CE) has become the first-line investigation procedure in some small bowel pathologies, and more recently, dedicated esophageal and colon CE have expanded the fields of application to include the upper and lower gastrointestinal disorders. During this time, CE has become increasingly popular among gastroenterologists, with more than 2 million capsule examinations performed worldwide, and nearly 3000 PubMed-listed studies on its different aspects published. This huge interest in CE may be explained by its non-invasive nature, patient comfort, safety, and access to anatomical regions unattainable via conventional endoscopy. However, CE has several limitations which impede its wider clinical applications, including the lack of therapeutic capabilities, inability to obtain biopsies and control its locomotion. Several research groups are currently working to overcome these limitations, while novel devices able to control capsule movement, obtain high quality images, insufflate the gut lumen, perform chromoendoscopy, biopsy of suspect lesions, or even deliver targeted drugs directly to specific sites are under development. Overlooking current limitations, especially as some of them have already been successfully surmounted, and based on the tremendous progress in technology, it is expected that, by the end of next 15 years, CE able to perform both diagnostic and therapeutic procedures will remain the major form of digestive endoscopy. This review summarizes the literature that prognosticates about the future developments of CE.

PillCam COLON 2© in Crohn’s disease: A new concept of pan-enteric mucosal healing assessment

AIM: To evaluate mucosal healing in patients with small bowel plus colonic Crohn’s disease (CD) with a single non-invasive examination, by using PillCam COLON 2^© (PCC2).

METHODS: Patients with non-stricturing nonpenetrating small bowel plus colonic CD in sustained corticosteroid-free remission were included. At diagnosis, patients had undergone ileocolonoscopy to identify active CD lesions, such as ulcers and erosions, and small bowel capsule endoscopy to assess the Lewis Score (LS). After ≥ 1 year of follow-up, patients underwent entire gastrointestinal tract evaluation with PCC2. The primary endpoint was assessment of CD mucosal healing, defined as no active colonic CD lesions and LS < 135.

RESULTS: Twelve patients were included (7 male; mean age: 32 years), and mean follow-up was 38 mo. The majority of patients (83.3%) received immunosuppressive therapy. Three patients (25%) achieved mucosal healing in both the small bowel and the colon, while disease activity was limited to either the small bowel or the colon in 5 patients (42%). It was possible to observe the entire gastrointestinal tract in 10 of the 12 patients (83%) who underwent PCC2.

CONCLUSION: Only three patients in sustained corticosteroid-free clinical remission achieved mucosal healing in both the small bowel and the colon, highlighting the limitations of clinical assessment when stratifying disease activity, and the need for pan-enteric endoscopy to guide therapeutic modification.

Wireless endoscopy in 2020: Will it still be a capsule?

Currently, the major problem of all existing commercial capsule devices is the lack of control of movement. In the future, with an interface application, the clinician will be able to stop and direct the device into points of interest for detailed inspection/diagnosis, and therapy delivery. This editorial presents current commercially-available new designs, European projects and delivery capsule and gives an overview of the progress required and progress that will be achieved -according to the opinion of the authors- in the next 5 year leading to 2020.