Capsule endoscopy of the esophagus

Developing sensor materials for screening intestinal diseases

Intestinal diseases that have high mortality and morbidity rates and bring huge encumbrance to the public medical system and economy worldwide, have always been the focus of clinicians and scientific researchers. Early diagnosis and intervention are valuable in the progression of many intestinal diseases. Fortunately, the emergence of sensor materials can effectively assist clinical early diagnosis and health monitoring. By accurately locating the lesion and sensitively analyzing the level of disease markers, these sensor materials can help to precisely diagnose the stage and state of lesions, thereby avoiding delayed treatment. In this review, we provide comprehensive and in-depth knowledge of diagnosing and monitoring intestinal diseases with the assistance of sensor materials, particularly emphasizing their design and application in bioimaging and biodetection. This review is dedicated to conveying practical applications of sensor materials in the intestine, critical analysis of their mechanisms and applications and discussion of their future roles in medicine. We believe that this review will promote multidisciplinary communication between material science, medicine and relevant engineering fields, thus improving the clinical translation of sensor materials.

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.

Esophageal Capsule Endoscopy in Children and Young Adults With Portal Hypertension

OBJECTIVES

Variceal hemorrhage (VH) is a serious complication of portal hypertension (PH). We evaluated the feasibility, safety, and clinical impact of esophageal capsule endoscopy (ECE) in pediatric and young adult patients with known or suspected PH.

METHODS

Children and young adults with PH at Boston Children's Hospital (2005-2017) were offered ECE for variceal screening or surveillance. Patient histories, ECE findings, and clinical outcomes were reviewed retrospectively.

RESULTS

One hundred and forty-nine ECE studies were performed in 98 patients (57.1% male patients) using 3 ECE devices for variceal screening (66.5%) or surveillance (33.5%). Three readers interpreted the studies (88.3%, 10.3%, and 1.4%, respectively). Median age was 16 years (IQR 13.7-18.5). One hundred and three ECE studies involved patients <18 years (69.1%). Fifteen patients (29 ECE studies) had a gastrointestinal (GI) bleeding (GIB) history, 5 in the preceding 12 months.Sixty-two ECE studies (44.9%) detected varices: 59 esophageal (40 small, 19 medium/large), 17 gastric, 6 duodenal. Other findings included: portal gastropathy (25, 18.1%), esophagitis (20, 14.5%), ulcers (5, 3.6%), erosions (31, 22.5%), heterotopic tissue (13, 9.4%), blood flecks (23, 16.7%), and mucosal scars (17, 12.3%). There were 2 transient capsule retentions and no major adverse events.ECE led to follow-up EGD in 11 (7 variceal banding) and medication initiation in 12 (4 proton-pump inhibitor, 7 nonselective beta blocker, 2 other) cases. Four patients had GIB within 12 months of ECE.

CONCLUSION

ECE is a feasible alternative to EGD for screening and surveillance of esophageal varices in children and young adults.

Efficacy of capsule endoscopy in patients with cirrhosis for the diagnosis of upper gastrointestinal lesions and small bowel abnormalities: a study protocol for prospective interventional study

INTRODUCTION AND AIMS

The role of capsule endoscopy (CE) in patients with liver cirrhosis (LC) has yet to be established; however, it is likely that it will remain a valuable diagnostic modality in several groups of patients with LC. The primary aims of the current prospective interventional study are to examine the prevalence for small bowel lesions and transit time of CE in the gastrointestinal tract in patients with LC with oesophageal varices (EVs) requiring endoscopic therapies.

METHODS AND ANALYSIS

The current study will be a single-centre prospective interventional study. Our study participants are LC subjects with portal hypertension who were determined to be necessary for prophylactic endoscopic therapies for EVs. From the view point of safety, patients with gastrointestinal obstruction or fistula or those being suspected of having gastrointestinal obstruction or fistula will be excluded from our study. Patients with implanted medical devices will be also excluded. CE will be performed prior to prophylactic endoscopic therapies in the same hospitalisation and relevant images will be analysed after 8 hours by expert endoscopists. This study will continue to recruit until 50 participants.

ETHICS AND DISSEMINATION

This study has received approval from the Institutional Review Board at Hyogo College of Medicine (approval no. 2680). The study protocol, informed assent form and other submitted files were reviewed and acknowledged. Final data will be publicly scattered regardless of the study results. A report releasing study results will be submitted for publication in a suitable journal after being finished in data collection.

TRIAL REGISTRATION NUMBER

UMIN000028433 (https://upload.umin.ac.jp/).

Medical capsule robots: A renaissance for diagnostics, drug delivery and surgical treatment

The advancements in electronics and the progress in nanotechnology have resulted in path breaking development that will transform the way diagnosis and treatment are carried out currently. This development is Medical Capsule Robots, which has emerged from the science fiction idea of robots travelling inside the body to diagnose and cure disorders. The first marketed capsule robot was a capsule endoscope developed to capture images of the gastrointestinal tract. Today, varieties of capsule endoscopes are available in the market. They are slightly larger than regular oral capsules, made up of a biocompatible case and have electronic circuitry and mechanisms to capture and transmit images. In addition, robots with diagnostic features such as in vivo body temperature detection and pH monitoring have also been launched in the market. However, a multi-functional unit that will diagnose and cure diseases inside the body has not yet been realized. A remote controlled capsule that will undertake drug delivery and surgical treatment has not been successfully launched in the market. High cost, inadequate power supply, lack of control over drug release, limited space for drug storage on the capsule, inadequate safety and no mechanisms for active locomotion and anchoring have prevented their entry in the market. The capsule robots can revolutionize the current way of diagnosis and treatment. This paper discusses in detail the applications of medical capsule robots in diagnostics, drug delivery and surgical treatment. In diagnostics, detailed analysis has been presented on wireless capsule endoscopes, issues associated with the marketed versions and their corresponding solutions in literature. Moreover, an assessment has been made of the existing state of remote controlled capsules for targeted drug delivery and surgical treatment and their future impact is predicted. Besides the need for multi-functional capsule robots and the areas for further research have also been highlighted.

Recent Advances in Non-invasive Esophageal Tissue Sampling

PURPOSE OF REVIEW

The costs to society and accuracy of screening for esophageal cancer and other esophageal diseases with standard endoscopy are formidable. As a result, the applicability of endoscopy as a general screening tool has been challenged.

RECENT FINDINGS

To maintain accuracy but reduce the price of endoscopy on society, multiple adjunct or replacement technologies are being developed that are less expensive and more easily applied. These devices include image-enhancing techniques that more reliably identify dysplasia and cancer reducing the need for extensive biopsy sampling during standard endoscopy. They also include ambulatory forms for procuring esophageal imaging including smaller endoscopes and capsule endoscopy. Finally, some of the newer methods either obtain samples of esophageal tissue through bedside maneuvers not requiring endoscopy or retrieve information about mucosal inflammation and function without the need to procure esophageal tissue. There is an exciting future for esophageal diagnosis with tools that will save cost and/or provide greater accuracy and safety for some of the most common esophageal disorders.

Emerging endoscopic techniques for the identification of esophageal disease

Esophageal diseases, both benign and malignant, impose an increasing burden to global health. In the West, gastroesophageal reflux disease (GERD) and Barrett's esophagus are increasing in prevalence and impact. In the East, squamous esophageal cancer remains a large burden, but increasingly, precancerous lesions related to GERD are recognized. We review the various advanced endoscopic techniques that have been developed to improve the accuracy of endoscopic identification of esophageal disease. These techniques are designed to increase the sensitivity of detecting disease and high-risk lesions, enable targeted biopsies, decrease total number of biopsies and costs for surveillance, but also guide therapy in real-time. After proper clinical validation, the widespread use of these technologies will lead to improved outcomes, mostly in cancer prevention.

Evaluation of performance of the Omni mode for detecting video capsule endoscopy images: A multicenter randomized controlled trial

BACKGROUND AND STUDY AIMS

Olympus recently developed a new algorithm called Omni mode that discards redundant video capsule endoscopy (VCE) images. The current study aimed to demonstrate the non-inferiority of the Omni mode in terms of true positives (TPs) and the superiority of the Omni mode with regard to reading time against a control (ordinary ES-10 system).

PATIENTS AND METHODS

This multicenter prospective study included 40 patients with various small bowel diseases. VCE images were evaluated by 7 readers and 3 judging committee members. Two randomly allocated readers assessed the VCE images obtained using the 2 modalities for each patient. The order of the modalities was switched between the 2 readers and the interval between readings by the same reader was 2 weeks. The judging committee predefined clinically relevant lesions as major lesions and irrelevant lesions as minor lesions. The number of TPs for major and minor lesions and the reading times were compared between the modalities. The predefined non-inferiority margin for the TP ratio of the Omni mode compared with the control was 0.9.

RESULTS

The estimated TP ratios and 95 % confidence intervals for total, major, and minor lesions were 0.87 (0.80 - 0.95), 0.93 (0.83 - 1.04), and 0.83 (0.74 - 0.94), respectively. Although non-inferiority was not demonstrated, the rate of detection of major lesions was not significantly different between the modalities. The reading time was significantly lower when using the Omni mode than when using the control.

CONCLUSIONS

The Omni mode may be only appropriate for the assessment of major lesions.

Screening for Barrett's Esophagus

There is substantial interest in identifying patients with premalignant conditions such as Barrett's esophagus (BE), to improve outcomes of subjects with esophageal adenocarcinoma. However, there is limited consensus on the rationale for screening, the appropriate target population, and optimal screening modality. Recent progress in the development and validation of minimally invasive tools for BE screening has reinvigorated interest in BE screening. BE risk scores combining clinical, anthropometric, and laboratory variables are being developed that may allow more precise targeting of screening to high-risk individuals. This article reviews and summarizes data on recent progress and challenges in screening for BE.

Screening for Barrett's Esophagus

The large increase in the incidence of esophageal adenocarcinoma in the West during the past 30 years has stimulated interest in screening for Barrett's esophagus (BE), a precursor to esophageal cancer. Effective endoscopic treatments for dysplasia and intramucosal cancer, coupled with screening programs to detect BE, could help reverse the increase in the incidence of esophageal cancer. However, there are no accurate, cost-effective, minimally invasive techniques available to screen for BE, reducing the enthusiasm of gastroenterologists. Over the past 5 years, there has been significant progress in the development of screening technologies. We review existing and developing technologies, new minimally invasive imaging techniques, nonendoscopic devices for cell collection, and biomarkers that can be measured in blood or stool samples. We discuss the status of these approaches, data from clinical studies of their effects, and their anticipated strengths and weaknesses in screening. The area is rapidly evolving, and new tools will soon be ready for prime time.

Magnetically guided capsule versus conventional gastroscopy for upper abdominal complaints: a prospective blinded study

OBJECTIVES

Upper gastrointestinal endoscopy is mostly performed under sedation and has a low yield of relevant gastric lesions in patients without alarm symptoms. Simpler screening tests such as capsule endoscopy could be helpful, but gastric visualization is insufficient with the current passive capsules. A magnetically guided gastric capsule was prospectively evaluated in patients with routine indications for gastroscopy.

METHODS

A total of 189 symptomatic patients (105 male; mean age 53 y) from 2 French centers subsequently and blindly underwent capsule and conventional gastroscopy by 9 and 6 examiners, respectively. The final gold standard was unblinded conventional gastroscopy with biopsy under propofol sedation. Main outcome was accuracy (sensitivity/specificity) of capsule gastroscopy for diagnosis of major gastric lesions, defined as those lesions requiring conventional gastroscopy for biopsy or removal.

RESULTS

Twenty-three major lesions were found in 21 patients. Capsule accuracy was 90.5% [95% confidence interval (CI), 85.4%-94.3%] with a specificity of 94.1% (95% CI, 89.3%-97.1%) and a sensitivity of 61.9% (95% CI, 38%-82%). Accuracy did not correlate with lesion location, gastric luminal visibility, examiner case volume, or examination time. Of the remaining 168 patients, 94% had minor and mostly multiple lesions; the capsule made a correct diagnosis in 88.1% (95% CI, 82.2%-92.6%), with gastric visibility and lesion location in the proximal stomach having significant influence. All patients preferred capsule gastroscopy.

CONCLUSIONS

In a prospective and strictly blinded study, magnetically guided capsule gastroscopy was shown to be feasible in clinical practice and was clearly preferred by patients. Improvements in capsule technology may render this technique a future alternative to gastroscopy.

Comparative acceptability of transnasal esophagoscopy and esophageal capsule esophagoscopy: a randomized, controlled trial in veterans

BACKGROUND

EGD screening for Barrett's esophagus (BE) is costly, with insufficient evidence to support its effectiveness.

OBJECTIVE

To compare acceptance and tolerability of 2 novel, office-based, endoscopic screening techniques done on nonsedated patients.

DESIGN

Randomized block study design with allocation concealment.

SETTING

Outpatient clinic setting at a Veterans Affairs medical center.

PATIENTS

A total of 184 veterans with or without GERD symptoms.

INTERVENTIONS

Transnasal esophagoscopy (TNE) or esophageal capsule esophagoscopy (ECE).

MAIN OUTCOME MEASUREMENTS

Acceptance and tolerability of TNE and ECE and effectiveness of BE screening.

RESULTS

Esophageal screening was accepted by 184 of 1210 (15.2%) veterans. The majority were men (96%) and African American (58%), with a mean (± standard deviation) age of 58.9 (± 8.1) years. Five TNE participants (5%) and 2 ECE participants (2%) refused the assigned procedure after randomization (P = .25). Eleven patients (12.6%) randomized to TNE crossed the minimal clinically important threshold for overall procedure tolerability, as opposed to no patients randomized to ECE (P = .001). Effectiveness of BE screening was not significantly different in both procedures (TNE vs ECE = 3.2% vs 5.4%; P = .47). Overall, BE was present in 8 of 75 white participants (10.6%) and in 0 of 107 African American participants (P < .001).

LIMITATIONS

The general veteran population may not reflect the screening population for BE.

CONCLUSION

Despite a small proportion of veterans expressing interest in esophageal screening, both TNE and ECE were feasible in the outpatient clinic setting and were accepted by >95% of participants who did express an interest. Screening was effective only in white participants. Moderate differences in tolerability between TNE and ECE notwithstanding, cost considerations along with availability of equipment and trained personnel should guide the modality to be used for BE screening.

Detection of neoplastic gastric lesions using capsule endoscopy: pilot study

Objectives. Capsule endoscopy is relatively noninvasive method and its use extends from the small bowel to the esophagus and colon. The aim of this study was to evaluate the feasibility and acceptability of capsule endoscopy for neoplastic gastric lesions. Methods. Capsule endoscopy (Pillcam ESO) was performed within 48 hours of esophagogastroduodenoscopy for eight patients who were diagnosed with gastric cancers, the size of which were less than 4 cm and who presented written consent. Patients changed position in a specified designed sequence every 30 seconds after capsule ingestion. Position change was repeated with ingestion of an effervescent agent. The rate of detection of intragastric lesions, observation of normal gastric anatomy and patient satisfaction between capsule endoscopy and esophagogastroduodenoscopy were compared. Results. Capsule endoscopy found four out of eight gastric lesions. The gastroesophageal junction was observed in seven of the eight cases, pyloric ring in five of the eight cases, and gastric angle in four of the eight cases. The patient satisfaction assessment questionnaire rated capsule endoscopy significantly higher than upper endoscopy in all categories. Conclusions. Capsule endoscopy was less effective than esophagogastroduodenoscopy and showed limited value in this feasibility study.

Diagnosis and management of Barrett's esophagus: What's next?

The past decade has led to marked improvements in our understanding regarding the pathogenesis and risk of progression of Barrett's esophagus (BE), enhanced imaging technology to improve dysplasia detection, and the development and refinement of endoscopic techniques, such as mucosal ablation and endoscopic mucosal resection(EMR), to eradicate BE. However, many questions remain including identifying which, if any, candidates are most appropriate for screening for BE; how to improve current surveillance protocols; predicting which patients with BE will develop neoplastic progression; identifying the most appropriate candidates for endoscopic eradication therapy; developing algorithms for appropriate management posteradication; and understanding the potential role of chemoprophylaxis. This article describes potential future advances regarding screening, surveillance, risk stratification, endoscopic eradication therapies, and chemoprevention and provides a potential future management strategy for patients with BE.

Remote magnetic control of a wireless capsule endoscope in the esophagus is safe and feasible: results of a randomized, clinical trial in healthy volunteers

BACKGROUND

Remote control of esophageal capsule endoscopes could enhance diagnostic accuracy.

OBJECTIVE

To assess the safety and efficacy of remote magnetic manipulation of a modified capsule endoscope (magnetic maneuverable capsule [MMC]; Given Imaging Ltd, Yoqneam, Israel) in the esophagus of healthy humans.

DESIGN

Randomized, controlled trial.

SETTING

Academic hospital.

PATIENTS

This study involved 10 healthy volunteers.

INTERVENTION

All participants swallowed a conventional capsule (ESO2; Given Imaging) and a capsule endoscope with magnetic material, the MMC, which is activated by a thermal switch, in random order (1 week apart). An external magnetic paddle (EMP; Given Imaging) was used to manipulate the MMC within the esophageal lumen. MMC responsiveness was evaluated on a screen showing the MMC film in real time.

MAIN OUTCOME MEASUREMENTS

Safety and tolerability of the procedure (questionnaire), responsiveness of the MMC to the EMP, esophageal transit time, and visualization of the Z-line.

RESULTS

No adverse events occurred apart from mild retrosternal pressure (n = 5). The ability to rotate the MMC around its longitudinal axis and to tilt it by defined movements of the EMP was clearly demonstrated in 9 volunteers. Esophageal transit time was highly variable for both capsules (MMC, 111-1514 seconds; ESO2, 47-1474 seconds), but the MMC stayed longer in the esophagus in 8 participants (P < .01). Visualization of the Z-line was more efficient with the ESO2 (inspection of 73% ± 18% of the circumference vs 33% ± 27%, P = .01).

LIMITATIONS

Magnetic forces were not strong enough to hold the MMC against peristalsis when the capsule approached the gastroesophageal junction.

CONCLUSION

Remote control of the MMC in the esophagus of healthy volunteers is safe and feasible, but higher magnetic forces may be needed.