Video capsule endoscopy:Perspectives of a revolutionary technique

Video capsule endoscopy (VCE) was launched in 2000 and has revolutionized direct endoscopic imaging of the gut. VCE is now a first-line procedure for exploring the small bowel in cases of obscure digestive bleeding and is also indicated in some patients with Crohn’s disease, celiac disease, and polyposis syndrome. A video capsule has also been designed for visualizing the esophagus in order to detect Barrett’s esophagus or esophageal varices. Different capsules are now available and differ with regard to dimensions, image acquisition rate, battery life, field of view, and possible optical enhancements. More recently, the use of VCE has been extended to exploring the colon. Within the last 5 years, tremendous developments have been made toward increasing the capabilities of the colon capsule. Although colon capsule cannot be proposed as a first-line colorectal cancer screening procedure, colon capsule may be used in patients with incomplete colonoscopy or in patients who are unwilling to undergo colonoscopy. In the near future, new technological developments will improve the diagnostic yield of VCE and broaden its therapeutic capabilities.

Contraindications for video capsule endoscopy

Video capsule endoscopy(VCE) has been applied in the last 15 years in an increasing field of applications. Although many contraindications have been put into perspective, some precautions still have to be considered. Known stenosis of the gastrointestinal tract is a clear contraindication for VCE unless surgery is already scheduled or at least has been considered as an optional treatment modality. In patients with a higher incidence of stenosis, as in an established diagnosis of Crohn's disease, clinical signs of obstruction, prior radiation or surgical small bowel resection, a preceding test with the self-dissolving patency capsule can override this contraindication. Endoscopic placement of the capsule should be considered in patients with swallowing disorders to avoid aspiration. Esophageal or gastric motility disorders may require endoscopic capsule transport or application of prokinetics if the real-time viewer proofs delayed transit. In pregnant women, VCE should be restricted to urgent cases where diagnosis cannot be postponed after delivery, as data on safety are missing. There is theoretical and clinical evidence that patients with implanted cardiac devices such as a pacemaker, cardioverters or left heart assist devices, can safely undergo VCE in spite of still existing contraindication by manufacturers. Children from the age of 2 years have safely undergone VCE. Although video capsules are not proven safe with magnetic resonance imaging(MRI), first single cases of patients incidentally undergoing MRI with an incorporated capsule have been reported, showing susceptibility artifacts but no signs of clinical harm.

Video capsule endoscopy in inflammatory bowel disease

Video capsule endoscopy (VCE) has evolved to become an important tool for the non-invasive examination of the small bowel, which hitherto had been relatively inaccessible to direct visualisation. VCE has been shown to play a role in monitoring the activity of small bowel Crohn’s disease and can be used to assess the response to anti-inflammatory treatment in Crohn’s disease. For those patients with Crohn’s disease who have undergone an intestinal resection, VCE has been assessed as a tool to detect post-operative recurrence. VCE may also aid in the reclassification of patients with a diagnosis of Inflammatory Bowel Disease Unclassified to Crohn’s disease. The evolution of colon capsule endoscopy (CCE) has expanded the application of this technology further. The use of CCE to assess the activity of ulcerative colitis has been described. This advance in capsule technology has also fuelled interest in its potential role as a minimally invasive tool to assess the whole of GI tract opening the possibility of its use for the panenteric assessment of Crohn’s disease. VCE is a safe procedure. However, the risk of a retained capsule is higher in patients with suspected or confirmed Crohn’s disease compared with patients having VCE examination for other indications. A retained video capsule is rare after successful passage of a patency capsule which may be utilised to pre-screen patients undergoing VCE. This paper describes the use of VCE in the assessment of inflammatory bowel disease.

Effect of small bowel transit time on accuracy of video capsule endoscopy in evaluating suspected small bowel bleeding

BACKGROUND Obscure small bowel bleeding is defined as gastrointestinal bleeding(GIB)that is unidentifiable with esophagogastroduodenoscopy and a colonoscopy with video capsule endoscopy(VCE)being the next gold standard step for evaluation.Small bowel transit time(SBTT)is a metric of a VCE study that is defined as the time the capsule takes to travel through the small intestine.AIM To determine if SBTT within the VCE study,correlates to overall detection of obscure small bowel bleeds.Furthermore,we attempted to identify any existing correlation between SBTT and re-bleeding after a negative VCE study.METHODS This is a single center retrospective analysis of VCE studies performed for overt and occult GIB at Einstein Medical Center,Philadelphia,between 2015 and 2019.Inclusion criteria primarily consisted of patients 18 years or older who had a VCE study done as part of the workup for a GIB.Patients with incomplete VCEs,poor preparation,or with less than 6 mo of follow up were excluded.A re-bleeding event was defined either as overt or occult within a 6-mo timeframe.Overt rebleeding was defined as Visible melena or hematochezia with>2 gm/dL drop in hemoglobin defined an overt re-bleeding event;whereas an unexplained>2 gm/dL drop in hemoglobin with no visible bleeding defined an occult re-bleed.RESULTS Results indicated that there was a significant and positive point biserial correlation between SBTT of 220 min and detection of a bleeding focus with a statistically significant p value of 0.008.However,the area under the curve was negligible when trying to identify a threshold time for SBTT to discriminate between risk of re-bleeding events after a negative VCE.CONCLUSION In terms of SBTT and association with accuracy of VCE finding a bleeding focus,220 min was found to be adequate transit time to accurately find a bleeding focus,when present.It was found that no threshold SBTT could be identified to help predict re-bleeding after a negative VCE.

Meckel's diverticulum diagnosis by video capsule endoscopy: A case report and review of literature

BACKGROUND Meckel’s diverticulum （MD） occurs predominantly in chil-dren and adolescents. It is rarely diagnosed in adults. Preoperative diagnosis is diffcult due to low sensitivity of the radiological imaging studies. The role of video capsule endoscopy （VCE） in the diagnosis of MD is unknown, and the endoscopic patterns are not defned. We will describe four of our cases of MD evaluated with VCE and make a review of the literature focusing on the endoscopic characteristics.CASE SUMMARYWe present four cases of MD confirmed by surgery. They were all adult males with ages going from 18 to 50 years, referred to our service from 2004 to 2018, due to obscure gastrointestinal bleeding （OGIB）. TheyGarcía-Compeán D et al . Merckel’s diverticulum diagnosis by VCEhad a history of 1 mo to 10 years of overt and occult bleeding episodes. Laboratory blood test showed an iron-deficiency anemia from 4 to 9 g/dL of hemoglo-bin that required multiple hospitalizations and blood transfusions in all cases. Repeated upper digestive endoscopies and colonoscopies were negative. Small bowel was examined with VCE, which revealed double lumen images in all cases, one with polyps and three with circumferential ulcers in the diverticulum. However, based on VCE findings, preoperative diagnosis of MD was suggested only in two patients. Capsule was retain-ed in one patient, which was recovered with surgery. The anatomopathological report revealed ulcerated ectopic gastric mucosa in all cases.CONCLUSIONVCE is useful for the diagnosis of MD. However, endo-scopic characteristics must be recognized in order to establish preoperative diagnosis.

Artificial intelligence as a means to improve recognition of gastrointestinal angiodysplasia in video capsule endoscopy

Gastrointestinal angiodysplasia(GIAD)is defined as the pathological process where blood vessels,typically venules and capillaries,become engorged,tortuous and thin walled–which then form arteriovenous connections within the mucosal and submucosal layers of the gastrointestinal tract.GIADs are a significant cause of gastrointestinal bleeding and are the main cause for suspected small bowel bleeding.To make the diagnosis,gastroenterologists rely on the use of video capsule endoscopy(VCE)to“target”GIAD.However,the use of VCE can be cumbersome secondary to reader fatigue,suboptimal preparation,and difficulty in distinguishing images.The human eye is imperfect.The same capsule study read by two different readers are noted to have miss rates like other forms of endoscopy.Artificial intelligence(AI)has been a means to bridge the gap between human imperfection and recognition of GIAD.The use of AI in VCE have shown that detection has improved,however the other burdens and limitations still need to be addressed.The use of AI for the diagnosis of GIAD shows promise and the changes needed to enhance the current practice of VCE are near.

A Wireless Video Capsule Endoscopy System: Design and Realization

Wireless capsule endoscopy(CE), an image inspection technique, has been an important advancement in the diagnosis of gastrointestinal(GI) tract diseases. A video capsule endoscopy(VCE) system is analyzed in this study. A complementary metal oxide semiconductor(CMOS) analog image sensor is adopted, and other illumination, communication and energy modules are designed for functional realization. Measuring only φ11 mm ×25 mm, the VCE has a total power consumption of 52.5 m W, which enables it to work continuously for 8 h. The in vivo experiment on a living pig indicates that a clear video with high frame rate of 30 f/s can be obtained.

Understanding deep learning in capsule endoscopy: Can artificial intelligence enhance clinical practice?

Wireless capsule endoscopy(WCE)enables physicians to examine the gastrointestinal tract by transmitting images wirelessly from a disposable capsule to a data recorder.Although WCE is the least invasive endoscopy technique for diagnosing gastrointestinal disorders,interpreting a WCE study requires significant time effort and training.Analysis of images by artificial intelligence,through advances such as machine or deep learning,has been increasingly applied to medical imaging.There has been substantial interest in using deep learning to detect various gastrointestinal disorders based on WCE images.This article discusses basic knowledge of deep learning,applications of deep learning in WCE,and the implementation of deep learning model in a clinical setting.We anticipate continued research investigating the use of deep learning in interpreting WCE studies to generate predictive algorithms and aid in the diagnosis of gastrointestinal disorders.

Prediction models for recurrence in patients with small bowel bleeding

Obscure gastrointestinal bleeding(OGIB)has traditionally been defined as gastrointestinal bleeding whose source remains unidentified after bidirectional endoscopy.OGIB can present as overt bleeding or occult bleeding,and small bowel lesions are the most common causes.The small bowel can be evaluated using capsule endoscopy,device-assisted enteroscopy,computed tomography enterography,or magnetic resonance enterography.Once the cause of smallbowel bleeding is identified and targeted therapeutic intervention is completed,the patient can be managed with routine visits.However,diagnostic tests may produce negative results,and some patients with small bowel bleeding,regardless of diagnostic findings,may experience rebleeding.Predicting those at risk of rebleeding can help clinicians form individualized surveillance plans.Several studies have identified different factors associated with rebleeding,and a limited number of studies have attempted to create prediction models for recurrence.This article describes prediction models developed so far for identifying patients with OGIB who are at greater risk of rebleeding.These models may aid clinicians in forming tailored patient management and surveillance.

Double balloon enteroscopy in children:Diagnosis,treatment,and safety

AIM:To assess the feasibility and utility of double balloon enteroscopy(DBE)in the management of small bowel diseases in children. METHODS:Fourteen patients(10 males)with a median age of 12.9 years(range 8.1-16.7)underwent DBE; 5 for Peutz-Jeghers syndrome(PJ syndrome),2 for chronic abdominal pain,4 for obscure gastrointestinal (GI)bleeding,2 with angiomatous malformations(1 blue rubber bleb nevus syndrome)having persistent GI bleeding,and 1 with Cowden's syndrome with multiple polyps and previous intussusception.Eleven procedures were performed under general anesthesia and 3 with deep sedation. RESULTS:The entire small bowel was examined in 6 patients,and a length between 200 cm and 320 cm distal to pylorus in the remaining 8.Seven patients had both antegrade(trans-oral)and retrograde(transanal and via ileostomy)examinations.One patient underwent DBE with planned laparoscopic assistance.The remaining 6 had trans-oral examination only.The median examination time was 118 min(range 95-195). No complications were encountered.Polyps were detected and successfully removed in all 5 patients with PJ syndrome,in a patient with tubulo-villous adenoma of the duodenum,in a patient with significant anemia and occult bleeding,and in a patient with Cowden's syndrome.A diagnosis was made in a patient with multiple angiomata not amenable to endotherapy,and in 1 with a discrete angioma which was treated with argon plasma coagulation.The source of bleeding was identified in a further patient with varices.DBE was normal or revealed minor mucosal friability in the remaining 3 patients.Hence a diagnostic yield of 11/14 with therapeutic success in 9/14 was achieved. CONCLUSION:Double balloon enteroscopy can be a useful diagnostic and therapeutic tool for small bowel disease in children,allowing endo-therapeutic intervention beyond the reach of the conventional endoscope.

Update on imaging of Peutz-Jeghers syndrome

Peutz-Jeghers syndrome(PJS) is a rare, autosomal dominant disease linked to a mutation of the STK 11 gene and is characterized by the development of benign hamartomatous polyps in the gastrointestinal tract in association with a hyperpigmentation on the lips and oral mucosa. Patients affected by PJS have an increased risk of developing gastrointestinal and extra-digestive cancer. Malignancy most commonly occurs in the smallbowel. Extra-intestinal malignancies are mostly breast cancer and gynecological tumors or, to a lesser extent, pancreatic cancer. These polyps are also at risk of acute gastrointestinal bleeding, intussusception and bowel obstruction. Recent guidelines recommend regular smallbowel surveillance to reduce these risks associated with PJS. Small-bowel surveillance allows for the detection of large polyps and the further referral of selected PJS patients for endoscopic enteroscopy or surgery. Video capsule endoscopy, double balloon pushed enteroscopy,multidetector computed tomography and magnetic resonance enteroclysis or enterography, all of which are relatively new techniques, have an important role in the management of patients suffering from PJS. This review illustrates the pathological, clinical and imaging features of small-bowel abnormalities as well as the role and performance of the most recent imaging modalities for the detection and follow-up of PJS patients.

Treatment of gastrointestinal bleeding in left ventricular assist devices:A comprehensive review

Left ventricular assist devices(LVAD)are increasingly become common as life prolonging therapy in patients with advanced heart failure.Current devices are now used as definitive treatment in some patients given the improved durability of continuous flow pumps.Unfortunately,continuous flow LVADs are fraught with complications such as gastrointestinal(GI)bleeding that are primarily attributed to the formation of arteriovenous malformations.With frequent GI bleeding,antiplatelet and anticoagulation therapies are usually discontinued increasing the risk of life-threatening events.Small bowel bleeds account for 15%as the source and patients often undergo multiple endoscopic procedures.Treatment strategies include resuscitative measures and endoscopic therapies.Medical treatment is with octreotide.Novel treatment options include thalidomide,angiotensin converting enzyme inhibitors/angiotensinⅡreceptor blockers,estrogen-based hormonal therapies,doxycycline,desmopressin and bevacizumab.Current research has explored the mechanism of frequent GI bleeds in this population,including destruction of von Willebrand factor,upregulation of tissue factor,vascular endothelial growth factor,tumor necrosis factor-α,tumor growth factor-β,and angiopoetin-2,and downregulation of angiopoetin-1.In addition,healthcare resource utilization is only increasing in this patient population with higher admissions,readmissions,blood product utilization,and endoscopy.While some of the novel endoscopic and medical therapies for LVAD bleeds are still in their development stages,these tools will yet be crucial as the number of LVAD placements will likely only increase in the coming years.

Muscovite is protective against non-steroidal anti-inflammatory drug-induced small bowel injury

AIM: To evaluate the effect of muscovite in preventing small bowel injury induced by nonsteroidal anti-inflammatory drugs (NSAIDs).

Comment on “Artificial intelligence in gastroenterology: A state-ofthe- art review”

Colon capsule endoscopy(CCE)was introduced nearly two decades ago.Initially,it was limited by poor image quality and short battery time,but due to technical improvements,it has become an equal diagnostic alternative to optical colonoscopy(OC).Hastened by the coronavirus disease 2019 pandemic,CCE has been introduced in clinical practice to relieve overburdened endoscopy units and move investigations to out-patient clinics.A wider adoption of CCE would be bolstered by positive patient experience,as it offers a diagnostic investigation that is not inferior to other modalities.The shortcomings of CCE include its inability to differentiate adenomatous polyps from hyperplastic polyps.Solving this issue would improve the stratification of patients for polyp removal.Artificial intelligence(AI)has shown promising results in polyp detection and characterization to minimize incomplete CCEs and avoid needless examinations.Onboard AI appears to be a needed application to enable near-real-time decision-making in order to diminish patient waiting times and avoid superfluous subsequent OCs.With this letter,we discuss the potential and role of AI in CCE as a diagnostic tool for the large bowel.

Optimization Design and Experiment of the Radio Frequency Transmission Utilized in Video Capsule Endoscope

In view of fuzzy and unstable images received in video capsule endoscopy, and the poor communication effect, an improved radio frequency(RF) transmission circuit module with low power consumption and helix antenna is designed to improve the performance of video transmission and to extend the working time of the capsule. Simulation and analysis of the circuits and antenna with HFSS12 and ADS2011 software are highlighted.Video capsule endoscope prototypes are made and evaluated to verify the feasibility of the proposed design. In vitro tests and animal experiments show that the results of the antenna tests basically meet the simulation, and the power consumption of RF circuit is 15.9 mV. The video capsule endoscope works well with the receiver with multiple receiving antennas, and the working time is more than 9 h. It can realize the wireless transmission of the video data, and images received are clear and stable in comparison with the previous designs.