Double-balloon endoscopy: past, present, and future

Classification Predictive Model for Air Leak Detection in Endoworm Enteroscopy System

Current enteroscopy techniques present complications that are intended to be improved with the development of a new semi-automatic device called Endoworm. It consists of two different types of inflatable cavities. For its correct operation, it is essential to detect in real time if the inflatable cavities are malfunctioning (presence of air leakage). Two classification predictive models were obtained, one for each cavity typology, which must discern between the "Right" or "Leak" states. The cavity pressure signals were digitally processed, from which a set of features were extracted and selected. The predictive models were obtained from the features, and a prior classification of the signals between the two possible states was used as input to different supervised machine learning algorithms. The accuracy obtained from the classification predictive model for cavities of the balloon-type was 99.62%, while that of the bellows-type was 100%, representing an encouraging result. Once the models are validated with data generated in animal model tests and subsequently in exploratory clinical tests, their incorporation in the software device will ensure patient safety during small bowel exploration.

Single-centre empirical analysis of double-balloon enteroscopy in the diagnosis and treatment of small bowel diseases: A retrospective study of 466 cases

BACKGROUND AND OBJECTIVE

The diagnosis and treatment of small bowel diseases (SBDs) has always been a challenge. The purpose of this study was to evaluate the value of double-balloon enteroscopy (DBE) in the diagnosis and treatment of small bowel diseases.

METHOD

The clinical data of 466 patients who underwent double-balloon enteroscopy (DBE) in the Endoscope Center of Gastroenterology Department of the First People's Hospital of Yunnan Province from Jan. 2015 to Dec. 2020 were analysed retrospectively. The factors included age, sex, indications, endoscopic treatment results, pathological results, discharge diagnosis and so on.

RESULTS

A total of 370 patients underwent 466 double-balloon enteroscopies, among whom 274 underwent one examination and 96 received two-way examinations (oral and transanal approaches). Abnormalities were detected in 299 cases, with a detection rate of 80.81% (299/370). The common indications were occult gastrointestinal bleeding (OGIB) (30.8%, 114/370) and abdominal pain (28.3%, 105/370). The diagnosis rates were 64.9% and 77.1%, respectively. The common positive findings included nonspecific inflammation/erosion (60 cases), ulcers (34 cases), diverticulum (32 cases), polyps (26 cases) and Crohn's disease (CD) (24 cases). The common tumours were lymphoma(12 cases), adenocarcinoma(11 cases) and stromal tumour(8 cases). Lymphoma was mostly located in the ileum, while stromal tumours and adenocarcinoma were mostly located in the duodenum and jejunum. The main endoscopic intervention measures were haemostasis and polypectomy, including haemostatic clip, argon plasma coagulation (APC), endoscopic mucosal resection (EMR), endoscopic trap resection, endoscopic foreign body extraction and other operations, without serious complications.

CONCLUSION

DBE has a high success rate in the diagnosis and treatment of some SBDs, and it is a safe and effective management method.

Novel ultrathin double-balloon endoscopy for the diagnosis of small-bowel diseases: a multicenter nonrandomized study

BACKGROUND

This study aimed to compare the markers of potential pancreatic injury during antegrade double-balloon endoscopy (DBE) using the newly developed ultrathin EN-580XP system and the conventional EN-580T system.

METHODS

Patients who were scheduled for antegrade DBE during daily clinical practice were enrolled. Clinical background, adverse events, and laboratory data of patients were compared between those who underwent endoscopy using the EN-580XP system and those in whom the EN-580T system was used. The primary end points were pancreatic hyperamylasemia and hyperlipasemia after DBE.

RESULTS

A total of 295 cases were registered. Pancreatic hyperamylasemia occurred in 2 of 92 patients (2.2 %) in the EN-580XP group and in 28 of 147 patients (19.1 %) in the EN-580 T diagnosis group (P < 0.001). Hyperlipasemia was significantly different between the two groups (1.1 % [EN-580XP] vs. 13.6 % [EN-580 T diagnosis]; P < 0.001). Acute pancreatitis occurred in four patients (7.1 %) in the EN-580 T therapy group. Multiple logistic regression analyses revealed that the endoscope type EN-580 T was significantly associated with pancreatic hyperamylasemia (adjusted odds ratio [OR] 8.63, 95 % confidence interval [CI] 1.97 - 37.70; P < 0.01) and hyperlipasemia (adjusted OR 13.10, 95 %CI 1.70 - 100.70; P = 0.01).

CONCLUSIONS

The EN-580XP system seemed less harmful to the pancreas during antegrade DBE.

Diagnosis and therapy using double-balloon endoscopy for small bowel disease: experience from a Chinese tertiary hospital

Objective

To evaluate the clinical efficacy of double-balloon endoscopy (DBE) for small bowel disease (SBD).

Methods

The clinical and endoscopic data of patients who underwent DBE in a Chinese tertiary hospital from January 2006 to December 2019 were retrospectively reviewed. The patients were divided into three groups by age: the young group (<45 years), middle-aged group (45–65 years), and older group (>65 years).

Results

In total, 1177 patients who underwent 2134 DBE procedures were included. The anterograde and retrograde route was used in 1111 and 1023 procedures, respectively. The most common reason for performing DBE was suspected small bowel bleeding (SSBB) (53.1%), and the most common SBD was Crohn's disease (CD) (18.1%). Hemostasis was the predominant endoscopic therapy (54.3%). The total complication rate was 0.8%. The incidence of CD was highest in the young group, and the incidence of tumors was highest in the older group; these findings were consistent both among the overall patient population and among patients with SSBB.

Conclusions

DBE is effective and safe for the diagnosis and treatment of SBD and is considered to have great potential as a first-line method for diagnosing SBD.

Diaphragm disease associated with nonsteroidal anti-inflammatory drugs mimicking intestinal tumor: A case report

INTRODUCTION

Diaphragm disease is rare and caused by intestinal obstruction due to nonsteroidal anti-inflammatory drugs (NSAIDs). Given the availability of video capsule endoscopy (VCE) and balloon enteroscopy (BE) this disease will be diagnosed more often.

PRESENTATION OF CASE

A 73-year-old man was presented to our hospital for persistent nausea and vomiting. Abdominal ultrasound and computed tomography revealed small-bowel thickening, stricture in the terminal ileum, and dilation of the proximal small intestine. Differential diagnosis included ileal lymphoma and multiple ileal adenocarcinomas, and a diagnostic laparoscopy was performed. Twenty-centimeter of ileum was resected by primary ileo-ileal anastomosis. On pathological examination, fibrosis of the submucosa was identified, and erosions and numerous inflammatory cells reaching the submucosa were also identified from the specimen.

DISCUSSION

The preoperative diagnosis of diaphragm disease is sometimes challenging due to its uncharacteristic symptoms; moreover, radiological findings are usually indefinite and distinctive. Currently, the main treatment for diaphragm disease is surgery.

CONCLUSION

We have documented a case of intestinal obstruction by NSAIDs. However, it is desirable to determine the course of treatment based on small bowel endoscopic dilatation cases in the future.

The role of double-balloon enteroscopy in reducing the maximum size of polyps in patients with Peutz-Jeghers syndrome: 12-year experience

OBJECTIVE

This study aimed to evaluate the role of double-balloon enteroscopy (DBE) in treating intestinal polyps in patients with Peutz-Jeghers syndrome (PJS).

METHODS

All patients diagnosed with PJS who underwent a polypectomy under DBE from October 2006 to December 2018 were enrolled. Their clinical records, including surgical history, the method of DBE insertion, the number of DBE procedures, and the maximum size and number of the resected polyps, were retrospectively reviewed.

RESULTS

Altogether 97 patients were enrolled. For both antegrade and retrograde DBE the maximum size of the resected polyps during the second hospitalization was significantly smaller than that during the first hospitalization (antegrade DBE: [2.13 ± 1.51] cm vs [3.63 ± 0.92] cm, P = 0.012; retrograde DBE: [1.20 ± 1.10] cm vs [2.95 ± 1.95] cm, P = 0.03), but was significantly larger than that during the third hospitalization (antegrade DBE: [2.13 ± 1.51] cm vs [0.88 ± 0.70] cm, P = 0.012; retrograde DBE: [1.20 ± 1.10] cm vs [0.46 ± 0.40] cm, P = 0.048). The interval between the second and third hospitalizations was significantly longer than that between the first and second hospitalizations ([899.00 ± 382.12] days vs [537.27 ± 326.28] days, P = 0.027). The success rate of total enteroscopy was 58.3% (28/48), which was not affected by a history of laparotomy (61.5% vs 52.4%, P = 0.528). The complication rate was 4.4%.

CONCLUSION

DBE is clinically safe and effective for the diagnosis and treatment of intestinal polyps in patients with PJS.

Enteroscopy in the Elderly: Review of Procedural Aspects, Indications, Yield, and Safety

Background

As human longevity continues to increase, age-related diseases are more common, which leads to a higher use of gastroenterology services. Endoscopic procedures are generally considered to be of higher risk in the elderly with multiple comorbidities. However, some endoscopic techniques have already been proved to be well tolerated in the elderly.

Summary

<underline></underline>Enteroscopy enables the nonsurgical diagnosis and therapeutic management of a wide variety of small bowel diseases. Although it has been shown to be safe and effective, with high diagnostic yield and therapeutic success rate in the general population, its safety and efficacy in the elderly is largely unknown, and there are still some concerns about its use in these patients.

Key Messages

This review will focus on enteroscopy in elderly people, taking into account patient and procedure characteristics, indications, findings, yield, and complication rate.

Failure Factors to Reach the Blind End Using a Short-Type Single-Balloon Enteroscope for ERCP with Roux-en-Y Reconstruction: A Multicenter Retrospective Study

Background

Failure factors in reaching the blind end (papillae of Vater, bilioenteric anastomosis) during short-type single-balloon enteroscope-assisted endoscopic retrograde cholangiopancreatography (sSBE-assisted ERCP) in patients with Roux-en-Y (R-Y) reconstruction remain to be evaluated.

Aims

We investigated the failure factors in such patients.

Methods

We retrospectively studied 253 initial sessions of sSBE-assisted ERCP at three endoscopy centers from April 2008 through September 2017, examining failure factors and complications associated with scope insertion in patients with R-Y reconstruction.

Results

R-Y reconstruction was performed in 157 patients (with gastrectomy: 122 patients; without gastrectomy plus bilioenteric anastomosis: 35 patients). R-Y without gastrectomy (p = 0.001; odds ratio (OR), 5.73; 95% confidence interval (CI), 2.07 to 16.01) and the presence of peritoneal dissemination (p = 0.021; OR, 4.71; 95% CI, 1.27 to 17.54) were significant failure factors. Insufficient sSBE length was the cause of failure in 17 (11%) of the 157 patients, and 13 (76%) of the 17 patients were with R-Y without gastrectomy. In cases of insufficient short-type length, using a long-type SBE significantly increased the success rate (p = 0.002). Gastrointestinal stenosis was a significant failure factor (p = 0.011) in patients with peritoneal dissemination. Perforation occurred in 2 patients who responded to conservative treatment.

Conclusions

Failure factors during sSBE-assisted ERCP were R-Y without gastrectomy and the presence of peritoneal dissemination.

Endoworm: A new semi-autonomous enteroscopy device

Using enteroscopes with therapeutic capacity to explore the small intestine entails certain limitations, including long exploration times, patient discomfort, the need for sedation, a high percentage of incomplete explorations and a long learning curve. This article describes the advances and setbacks encountered in designing the new Endoworm enteroscopy system, a semi-autonomous device consisting of a control unit and three cavities that inflate and deflate in such a way that the bowel retracts over the endoscope. The system can be adapted to any commercial enteroscope. Endoworm was tested in different intestine models: a polymethyl methacrylate rigid tube, an in vitro polyester urethane model, an ex vivo pig model and an in vivo animal model. The general behavior of the prototype was evaluated by experienced medical personnel. The mean distance covered through the lumen was measured in each cycle. The system was found to have excellent performance in the rigid tube and in the in vitro model. The ex vivo tests showed that the behavior depended largely on the mechanical properties of the lumen, while the in vivo experiments suggest that the device will require further modifications to improve its performance.

Safety and efficacy of small bowel polypectomy using a balloon-assisted enteroscope in pediatric patients with Peutz-Jeghers syndrome

INTRODUCTION AND AIMS

Peutz-Jeghers syndrome is an autosomal dominant inherited pathology characterized by gastrointestinal hamartomatous polyps, predominantly in the small bowel, and pigmented mucocutaneous lesions. Guidelines suggest polypectomy with a balloon-assisted enteroscope when polyps are larger than 10mm. Complications in adults can be as high as 6.8%, but there is little information on pediatric populations. Our aim was to describe the safety and efficacy of polypectomy in a group of pediatric patients with Peutz-Jeghers syndrome using balloon-assisted enteroscopy.

MATERIALS AND METHODS

A retrospective study was conducted at the Hospital de Especialidades del Centro Médico Nacional Siglo XXI on pediatric patients with Peutz-Jeghers syndrome that required balloon-assisted enteroscopy and polypectomy within the time frame of January 2010 and December 2015. Patients that underwent polypectomy with a push enteroscope were excluded from the study.

RESULTS

A total of 35 polypectomies were performed on 4 patients (female/male: 3/1). The mean age of the patients was 13.7 years (range:11-16). Twelve enteroscopies were carried out, 8 of which were anterograde. A single-balloon enteroscope was used in 7 procedures and a double-balloon enteroscope in 5. The mean size of the polyps was 1.6cm (range: 1-4cm). A major complication (acute pancreatitis) presented in only one case (8.3%). No other major complications associated with the procedures were observed.

CONCLUSION

Balloon-assisted enteroscopy with polypectomy in children is a safe and effective procedure, with complications similar to those reported in adults.

Non-steroidal anti-inflammatory drug-induced enteropathy

Non-steroidal anti-inflammatory drugs (NSAIDs) are well known to be associated with serious upper gastrointestinal complications, such as peptic ulcer, bleeding, perforation, and obstruction. Recently, attention has been mainly focused on the small bowel injuries caused by NSAIDs, and new endoscopic techniques such as capsule endoscopy and double balloon endoscopy can help in detecting such injuries. This article reviewed the epidemiology, pathogenesis, clinical manifestations, diagnosis, and treatment of small bowel injuries caused by NSAIDs. Small bowel injures by NSAIDs might occur with a similar frequency and extent as those observed in the upper gastrointestinal tract. The pathogenesis of NSAID-induced enteropathy is complex and not clearly understood. The various lesions observed in the small bowel, including petechiae, reddened folds, loss of villi, erosions, and ulcers can be detected by capsule endoscopy. A drug that could prevent or treat NSAID-induced enteropathy has not yet been developed. Therefore, further investigations should be performed to elucidate the pathogenesis of such enteropathy and develop suitable preventive and treatment strategies.

Evidences supporting the vascular etiology of post-double balloon enteroscopy pancreatitis: Study in porcine model

Double balloon enteroscopy (DBE) is an endoscopic technique broadly used to diagnose and treat small bowel diseases. Among the associated complications of the oral DBE, post-procedure pancreatitis has taken the most attention due to its gravity and the thought that it might be associated to the technique itself and anatomical features of the pancreas. However, as the etiology has not been clarified yet, this paper aims to review the published literature and adds new results from a porcine animal model. Biochemical markers, histological sections and the vascular perfusion of the pancreas were monitored in the pig during DBE practice. A reduced perfusion of the pancreas and bowel, the presence of defined hypoxic areas and disseminated necrotic zones were found in the pancreatic tissue of pigs. All these evidences contribute to support a vascular distress as the most likely etiology of the post-DBE pancreatitis.

Double-balloon enteroscopy in small bowel diseases: Eight years single-center experience in China

The aim of the study was to evaluate the diagnostic and therapeutic value of double-balloon entoroscopy (DBE) in small bowel diseases (SBDs) in China.A retrospective review of 674 consecutive patients who underwent DBE between January 2007 and November 2015 was conducted. Patients were divided into 3 groups by age, young group (<45 years), middle-aged group (45-65 years), and elderly group (>65 years). Data were collected with regard to demographics, clinical, endoscopic findings, complications, diagnostic yield, and management.A total of 729 DBE procedures were performed successfully in our series. More than 20 types of SBDs were found with the detection rate of 70.9%(517/729). The majority of patients were Crohn's disease (33.4%,225/674), followed by tumor (18.8%,127/674) and angioectasia (7.9%, 53/674). Endoscopic treatment was performed in 60 patients in which hemostasis (17,28.3%) and polypectomy (15,25%) were the predominant form of intervention used. Adverse events occurred in 6 patients (0.96%,6/729) including perforation, hemorrhage, aspiration pneumonia. No acute pancreatitis or other major complications occurred. Adenocarcinoma, GIST, and lymphoma were the most common tumor detected, the majority of tumors located in the jejunum (56.7%), The detection rate of angioectasia was also higher in the jejunum (54.7%),77.8% of Crohn's disease was located in the ileum. The positive rate of DBE in small bowel tumor and Crohn's disease were significantly higher than that of angioectasia (P<0.05). In young cohort, Crohn's disease (48.1%) was the most commonly diseases followed by tumor (10.4%) and nonspecific enteritis (7.1%). Yet in the elderly group, the majority of patients were tumor (27.6%); angioectasia (21.3%) was also detected frequently. The positive rate of capsule endoscopy was 75.44 %(202/268) which was a little high than DBE (67.9%, 182/268) (P > 0.05). The obscure gastrointestinal bleeding (OGIB) was the most common indication, and the diagnostic yield was 71.8%.DBE is a useful diagnostic and therapeutic tool with high clinical practice value for the investigation of SBDs. With growing experience of endoscopist, we believe that DBE must be kept in mind as the first-line modality for suspected SBDs.

Risk Factors of Acute Pancreatitis in Oral Double Balloon Enteroscopy

Double balloon enteroscopy (DBE) was introduced 15 years ago. The complications of diagnostic DBE are rare, acute pancreatitis is most redoubtable one (incidence about 0.3%). Hyperamylasemia after DBE seems to be a rather common condition respectively. The most probable cause seems to be a mechanical straining of the pancreas. We tried to identify patients in a higher risk of acute pancreatitis after DBE. We investigated several laboratory markers before and after DBE (serum cathepsin B, lactoferrin, E-selectin, SPINK 1, procalcitonin, S100 proteins, alfa-1-antitrypsin, hs-CRP, malondialdehyde, serum and urine amylase and serum lipase). Serum amylase and lipase rose significantly with the maximum 4 hours after DBE. Serum cathepsin and procalcitonin decreased significantly 4 hours after DBE compared to healthy controls and patients values before DBE. Either serum amylase or lipase 4 hours after DBE did not correlate with any markers before DBE. There was a trend for an association between the number of push-and-pull cycles and procalcitonin and urine amylase 4 hours after DBE; between procalcitonin and alfa-1-antitrypsin, cathepsin and hs-CRP; and between E-selectin and malondialdehyde 4 hours after DBE. We found no laboratory markers determinative in advance those patients in a higher risk of acute pancreatitis after DBE.

Long-Term Outcomes of NSAID-Induced Small Intestinal Injury Assessed by Capsule Endoscopy in Korea: A Nationwide Multicenter Retrospective Study

BACKGROUND/AIMS

We evaluated the long-term outcome and clinical course of patients of nonsteroidal anti-inflammatory drug (NSAID)-induced small intestinal injury by performing capsule endoscopy (CE).

METHODS

A multicenter retrospective study was conducted using data collected from the CE nationwide database registry, which has been established since 2002.

RESULTS

A total of 140 patients (87 males; mean age, 60.6±14.8 years) from the CE nationwide database registry (n=2,885) were diagnosed with NSAID-induced small intestinal injury and enrolled in our study. Forty-nine patients (35.0%) presented with a history of aspirin use and an additional 49 (35.0%) were taking NSAIDs without aspirin. The most prominent findings after performing CE were multiple ulcerations (n=82, 58.6%) and erosions or aphthae (n=32, 22.9%). During the follow-up period (mean, 15.9±19.0 months; range, 0 to 106 months), NSAID-induced small intestinal injury only recurred in six patients (4.3%). Older age and hypertension were positive predictive factors for recurrence.

CONCLUSIONS

These results suggest that the recurrence of NSAID-induced small bowel injury was not frequent in the presence of conservative treatment. Therefore, the initial diagnosis using CE and the medication history are important.

[Peutz-Jeghers syndrome manifested as massive melæna at CHU-JRA Madagascar hospital: a case report]

Le syndrome de Peutz-Jeghers (SPJ) est caractérisé par l'association d'une polypose digestive hamartomateuse et d'une lentiginose cutanéo-muqueuse. Les malades sont exposés à des complications mécaniques et hémorragiques. Il s'agit d'un syndrome de prédisposition au cancer. Notre étude a pour objectif de rappeler les diagnostiques d'un syndrome de Peutz-Jeghers, de connaitre les complications ainsi que les progrès thérapeutiques dans la prise en charge. Nous avons rapporté le cas d'un homme de 32 ans présentant un melaena massif. Il a été hospitalisé en service de réanimation chirurgicale pour état de choc hypovolémique difficile à contrôler. Il a nécessité une intervention chirurgicale pour arrêter l'hémorragie. Nous avons trouvé un polype hamartomateux dans le grêle qui a causé le saignement. Le diagnostic d'un Syndrome de Peutz-Jeghers a été posé devant la notion de lentiginose labiale pendant l'enfance. Lors de l'exploration clinique et paraclinique, il ne présente pas encore de cancer. A Madagascar, cette pathologie est encore mal connue. Dans la littérature, le syndrome de Peutz-Jeghers peut être révélé cliniquement ou au stade de complication comme l'hémorragie, l'invagination ou l'occlusion intestinale. Dans notre cas, la maladie est compliquée d'une hémorragie digestive avec état de choc hypovolémique. La polypectomie endoscopique par entéroscopie à double ballonnet permet de diminuer le recours à la chirurgie grêlique d'urgence. Le syndrome de Peutz-Jeghers est une affection rare. Mais il est important aux cliniciens de le connaitre et de penser à sa possibilité en cas d'hémorragie digestive.

Colorectal endoscopic submucosal dissection: Recent technical advances for safe and successful procedures

Endoscopic submucosal dissection (ESD) is very useful in en bloc resection of large superficial colorectal tumors but is a technically difficult procedure because the colonic wall is thin and endoscopic maneuverability is poor because of colonic flexure and extensibility. A high risk of perforation has been reported in colorectal ESD. To prevent complications such as perforation and unexpected bleeding, it is crucial to ensure good visualization of the submucosal layer by creating a mucosal flap, which is an exfoliated mucosa for inserting the tip of the endoscope under it. The creation of a mucosal flap is often technically difficult; however, various types of equipment, appropriate strategy, and novel procedures including our clip-flap method, appear to facilitate mucosal flap creation, improving the safety and success rate of ESD. Favorable treatment outcomes with colorectal ESD have already been reported in many advanced institutions, and appropriate understanding of techniques and development of training systems are required for world-wide standardization of colorectal ESD. Here, we describe recent technical advances for safe and successful colorectal ESD.

Clinical utility of a new endoscopic scoring system for Crohn’s disease

AIM: To evaluate the clinical value of the newly modified Simple Endoscopic Score for Crohn’s disease (mSES-CD).

METHODS: Seventy-six Crohn’s disease (CD) patients who underwent transanal double balloon endoscopy (DBE) in our hospital between 2003 and 2012 were retrospectively reviewed. DBE is defined as small intestinal endoscopy using two attached balloons. We included patients with stenosis which hampered passage of the scope and those who underwent DBE with observation for at least 80 cm from the ileocecal valve. Our new mSES-CD assesses the endoscopic activity of two consecutive small intestinal segments located 0-40 cm and 40-80 cm from the ileocecal valve by DBE, in addition to the activity of four colorectal segments. To compare the usefulness of mSES-CD with SES-CD, we similarly divided the patients into two groups according to total mSES-CD score (low disease activity group, < 4; high disease activity group, ≥ 4). The clinical value of mSES-CD in predicting clinical outcome in patients with CD was evaluated using the occurrence of surgery after DBE as an endpoint.

RESULTS: Median age of the 76 CD patients was 36 years (range, 16-71). Thirty-nine patients had stenosis which hampered passage of the DBE to 80 cm on the proximal side from the ileocecal valve. Median evaluable length of small intestine by DBE was 80 cm (range, 3-200). A total of 74 patients had one or more small intestinal lesions detected by DBE, of which 62 (83.8%) were within 80 cm of the ileocecal valve on the proximal side. Only two patients (2.7%) with proximal-side lesions more than 80 cm from the ileocecal valve did not have lesions within 80 cm. Patients with high mSES-CD scores showed significantly shorter surgery-free survival than those with low scores (P < 0.05). In contrast, surgery-free survival did not significantly differ between the low and high SES-CD groups (P > 0.05). Multivariate analysis by a Cox proportional hazards model identified mSES-CD as an independent factor for surgery-free survival.

CONCLUSION: mSES-CD is useful in evaluating the risk of surgery-free survival in patients with CD.

Factors affecting pancreatic hyperamylasemia in patients undergoing peroral single-balloon enteroscopy

BACKGROUND AND AIM

Acute pancreatitis following balloon-assisted enteroscopy is a rare but serious complication. The causative mechanism is uncertain and prevention strategies are not established. We conducted a retrospective study to clarify the risk factors for pancreatic hyperamylasemia.

METHODS

Eighty-four patients undergoing peroral single-balloon enteroscopy (SBE) were enrolled in this study. Serum pancreatic and salivary amylase levels were measured 2 h after endoscopic examination.

RESULTS

We experienced three patients with post-SBE pancreatitis. Factors predicting pancreatic hyperamylasemia were: (i) elderly patients; (ii) deeper insertion; and (iii) clockwise insertion. In contrast, younger age at examination was a significant factor observed in salivary hyperamylasemia.

CONCLUSIONS

It is important to measure pancreatic amylase and not total amylase after SBE. When carrying out peroral SBE, the distance of insertion should be reduced especially if the scope traces a clockwise loop or the subject is elderly.

Advances in balloon endoscopes

In September 2003, a double-balloon endoscope (DBE) composed of balloons attached to a scope and an overtube was released in Japan prior to becoming available in other parts of the world. The DBE was developed by Dr. Yamamoto (1), and 5 different types of scopes with different uses have already been marketed. In April 2007, a single-balloon small intestinal endoscope was released with a balloon attached only to the overtube as a subsequent model. This article presents a detailed account of the development of these scopes up to the present time.

Enteroscopy in small bowel Crohn’s disease: A review

Crohn’s disease (CD) is a chronic inflammatory condition of the gastrointestinal tract resulting in inflammation, stricturing and fistulae secondary to transmural inflammation. Diagnosis relies on clinical history, abnormal laboratory parameters, characteristic radiologic and endoscopic changes within the gastrointestinal tract and most importantly a supportive histology. The article is intended mainly for the general gastroenterologist and for other interested physicians. Management of small bowel CD has been suboptimal and limited due to the inaccessibility of the small bowel. Enteroscopy has had a significant renaissance recently, thereby extending the reach of the endoscopist, aiding diagnosis and enabling therapeutic interventions in the small bowel. Radiologic imaging is used as the first line modality to visualise the small bowel. If the clinical suspicion is high, wireless capsule endoscopy (WCE) is used to rule out superficial and early disease, despite the above investigations being normal. This is followed by push enteroscopy or device assisted enteroscopy (DAE) as is appropriate. This approach has been found to be the most cost effective and least invasive. DAE includes balloon-assisted enteroscopy, [double balloon enteroscopy (DBE), single balloon enteroscopy (SBE) and more recently spiral enteroscopy (SE)]. This review is not going to cover the various other indications of enteroscopy, radiological small bowel investigations nor WCE and limited only to enteroscopy in small bowel Crohn’s. These excluded topics already have comprehensive reviews. Evidence available from randomized controlled trials comparing the various modalities is limited and at best regarded as Grade C or D (based on expert opinion). The evidence suggests that all three DAE modalities have comparable insertion depths, diagnostic and therapeutic efficacies and complication rates, though most favour DBE due to higher rates of total enteroscopy. SE is quicker than DBE, but lower complete enteroscopy rates. SBE has quicker procedural times and is evolving but the least available DAE today. Larger prospective randomised controlled trial’s in the future could help us understand some unanswered areas including the role of BAE in small bowel screening and comparative studies between the main types of enteroscopy in small bowel CD.

Small bowel endoscopy in inflammatory bowel disease

Crohn disease (CD) is a chronic inflammatory bowel disease that affects the entire gastrointestinal tract but is most frequently localized to the large and small bowel. Small bowel endoscopy helps with the differential diagnosis of CD in suspected CD patients. Early diagnosis of CD is preferable for suspected CD conditions to improve chronic inflammatory infiltrates, fibrosis. Small bowel endoscopy can help with the early detection of active disease, thus leading to early therapy before the onset of clinical symptoms of established CD. Some patients with CD have mucosal inflammatory changes not in the terminal ileum but in the proximal small bowel. Conventional ileocolonoscopy cannot detect ileal involvement proximal to the terminal ileum. Small bowel endoscopy, however, can be useful for evaluating these small bowel involvements in patients with CD. Small bowel endoscopy by endoscopic balloon dilation (EBD) enables the treatment of small bowel strictures in patients with CD. However, many practical issues still need to be addressed, such as endoscopic findings for early detection of CD, application compared with other imaging modalities, determination of the appropriate interval for endoscopic surveillance of small bowel lesions in patients with CD, and long-term prognosis after EBD.

Consensus of the present and prospects on endoscopic diagnosis and treatment in East asian countries

Background and Aim. New diagnostic or therapeutic methods in endoscopy have been used. Current clinical application of these procedures is not well known. The aim of this study is to investigate the present situation on endoscopic diagnosis and treatment of gastrointestinal disorders in East Asian countries. Method. A representative member from the International Gastrointestinal Consensus Symposium Committee provided a questionnaire to physicians in China, Indonesia, Japan, Korea, the Philippines, and Thailand. Results. In total, 514 physicians including gastroenterologists, surgeons, and general practitioners enrolled. The most frequently occurring disorder as the origin of upper gastrointestinal bleeding is gastric ulcer. Capsule endoscopy is selected as the first choice for the diagnosis of small intestine bleeding. The second choice was double-balloon endoscopy or angiography. For patients with gastric adenoma, the number of physicians who choose endoscopic mucosal resection is larger than those selecting endoscopic submucosal dissection (ESD) in China, Indonesia, the Philippines, and Thailand. ESD is chosen first in Japan and Korea. Conclusion. New instruments or techniques on endoscopy have not come into wide use yet, and there is diversity in the situation on it in Asian countries. We should unify the endoscopic diagnostic criteria or treated strategy in patients with GI disease.

Effect of double-balloon enteroscopy on pancreas: an experimental porcine model

AIM

To evaluate the effect of double-balloon enteroscopy (DBE) on pancreas histology and levels of pancreatic enzymes.

METHODS

Conventional upper gastrointestinal endoscopy was performed on five control pigs. Oral DBE was performed with an EN-450T5 enteroscope on 20 pigs. Two experimental groups (10 pigs each) were defined according to DBE duration: 90 min for Group 1 and 140 min for group 2. During oral insertion, the balloons were not inflated in the descending part of the duodenum to avoid the minor duodenal papilla. Serum amylase, lipase and C-reactive protein (CRP) levels were monitored before the procedure and repeated every 30 min until the exploration was finished, as well as 24 h and 7 d after. After the procedure and for a total of 7 d, the pigs were observed twice a day for signs of decreased activity, irritability, vomiting or anorexia. Gross and microscopic examination of the pancreas was performed on day 7.

RESULTS

All animals tolerated DBE without clinical manifestations of acute pancreatitis. Experimental groups had higher levels of enzymes than the control group at 24 h. Throughout the exploration, the amylase levels increased significantly above the baseline 24 h after DBE, although the increase was not statistically significant and did not reach 20% of the baseline. An increase in lipase and CRP was observed at 24 h after the procedure, although by day 7, all enzymatic levels had returned to baseline. No differences between groups 1 and 2 were found for any enzyme and sampling site during and after the procedure. Similarly, no correlation between insertion depth and enzyme levels was observed. Direct in situ and post-removal inspection of the pancreas did not show any evidence of fluid collection, abscesses or hemorrhage. Histological examination of the pancreas from groups 1 and 2 revealed the existence of focal areas (0.14-0.26 mm2) of ischemic necrosis in 47.4% of the animals. In the pigs with damaged pancreas, the left lobe (tail) was always affected. However, this only happened in 83.3% of the samples from the right lobe (head) and in 33.3% of the samples from the body of the pancreas. Significant differences were found between the left lobe (tail) and the body for the percentage of affected pancreas. Both the size of the lesions and the percentage of affected pancreas were higher in the left pancreatic lobe (tail). The presence of the lesions was not related to the exploration length.

CONCLUSION

The increase in pancreatic enzymes after DBE could be related to focal points of pancreatic ischemic necrosis due to mechanical stress.

Endoscopic submucosal dissection--current success and future directions

More than 10 years have passed since endoscopic submucosal dissection (ESD) was first developed in Japan. ESD enables en bloc complete resection of superficial gastrointestinal neoplasms regardless of the size and location of the lesions. With improvements in techniques and devices, excellent therapeutic results have been achieved despite the inherent technical difficulties of this procedure. ESD aiming for curative treatment can be performed for gastrointestinal neoplasms without risk of lymph node metastasis. Accurate histopathologic examination of the resected specimen is required to determine the risk of lymph node metastasis, for which en bloc resection is beneficial. Owing to the high success rate of en bloc complete resection and accurate histopathologic examination, tumour recurrence rates after ESD are reported to be very low in Japan. Excellent results of ESD in a large number of cases have also been reported from other Asian countries such as South Korea, Taiwan and China. Although scepticism exists among Western clinicians regarding the application of ESD, it is developing slowly and reports indicate promising results in some European countries. With further development of technologies, such as endoscopic robotics, ESD could become the worldwide treatment of choice for early gastrointestinal neoplasms.

Recent advances in small bowel diseases: Part II

As is the case in all areas of gastroenterology and hepatology, in 2009 and 2010 there were many advances in our knowledge and understanding of small intestinal diseases. Over 1000 publications were reviewed, and the important advances in basic science as well as clinical applications were considered. In Part II we review six topics: absorption, short bowel syndrome, smooth muscle function and intestinal motility, tumors, diagnostic imaging, and cystic fibrosis.

Double-balloon endoscopy in clinical practice: where are we now?

Double-balloon endoscopy (DBE) was developed in 2000 for the diagnosis and treatment of small bowel diseases. Although use rates still differ between Eastern and Western countries, DBE quickly reached a broad global diffusion. Together with capsule endoscopy (CE), DBE represented 'a revolution' for the management of small bowel diseases because of its therapeutic capabilities. At present, the main indications for DBE in clinical practice are obscure gastrointestinal bleeding, Crohn's disease and familial polyposis. In the setting of obscure gastrointestinal bleeding, DBE seems to have similar diagnostic performances as capsule endoscopy, but it allows for a more definitive diagnosis and the treatment of identified lesions. The main contribution of DBE in the management of Crohn's disease patients is its therapeutic capabilities. Indeed, several recently published studies have suggested that endoscopic dilation of small bowel strictures can delay or, in the near future, could even replace surgical interventions. Also, for patients with familial polyposis syndromes, DBE can represent a viable alternative to small bowel surgery. The complication rate of DBE appears to be low; major complications, such as pancreatitis, bleeding and perforation, have been reported in approximately 1% of all diagnostic DBE whereas the complication rate for therapeutic procedures is about 5%.

Non-steroidal anti-inflammatory drug-induced enteropathy

Non-steroidal anti-inflammatory drugs (NSAIDs) are one of the most commonly prescribed drugs in the world. NSAID-induced lower gastrointestinal (GI) complications are increasing while upper GI complications are decreasing. Lower GI events accounted for 40% of all serious GI events in patients on NSAIDs. Capsule endoscopy and device assisted enteroscopy are available for detection of small intestinal lesions. Capsule endoscopy studies have demonstrated that NSAIDs use in healthy volunteers raised the incidence (55% to 75%) of intestinal damage. It appears that selective cyclooxygenase-2 inhibitors (coxibs) improved upper and lower GI safety based on results of clinical trials. Selective coxibs are still capable of triggering GI adverse events and cardiovascular toxicity issues were the main focus of concerns. Unfortunately, definite strategies are not available to prevent or heal NSAID-induced intestinal injuries. Thus, there is still a strong clinical need for effective drugs with improved safety profiles than the existing NSAIDs.

Nonsurgical management of small-bowel polyps in Peutz-Jeghers syndrome with extensive polypectomy by using double-balloon endoscopy

BACKGROUND

The major problem in the management of Peutz-Jeghers syndrome (PJS) is small-bowel polyps, which can cause intussusception and bleeding. Double-balloon endoscopy (DBE) enables endoscopic resection of small-bowel polyps.

OBJECTIVE

The aim of this study was to determine the efficacy and safety of endoscopic management of small-bowel polyps in PJS patients by using DBE.

DESIGN

Retrospective chart review.

SETTING

Single university hospital.

PATIENTS

Consecutive patients with PJS who underwent multiple sessions of DBE for evaluation or treatment of small-bowel polyps between September 2000 and April 2009.

INTERVENTIONS

Endoscopic resection of small-bowel polyps in PJS patients was performed by using DBE.

MAIN OUTCOME MEASUREMENTS

Efficacy, safety, and long-term laparotomy rate after the procedures were evaluated.

RESULTS

Fifteen patients (10 men, mean age 34.0 ± 15.8 years) underwent DBE for a mean 3.0 ± 1.0 sessions. The mean numbers of resected polyps larger than 20 mm significantly decreased as sessions advanced (first, 3.6; second, 1.3; third, 0.7; fourth, 0.4; and fifth, 1.0; P = .02). The mean maximum sizes of resected polyps also significantly decreased at each session: 33, 19, 12, 17, and 30 mm (P = .01). One patient had a perforation, but was managed conservatively. Other complications were pancreatitis (n = 2) and bleeding (n = 2). Only 1 patient underwent surgery for intussusception during the study period.

LIMITATIONS

This was a small single-center retrospective study of short duration.

CONCLUSIONS

Endoscopic management of small-bowel polyps in PJS patients by using DBE is safe and effective and avoids urgent laparotomy.

Comparison between double-balloon and single-balloon enteroscopy in therapeutic ERC after Roux-en-Y entero-enteric anastomosis

AIM: To compare the efficacy of double-balloon enteroscopy (DBE) and single-balloon enteroscopy (SBE) in therapeutic endoscopic retrograde cholangiography (ERC) in patients with Roux-en-Y entero-enteric anastomosis.

METHODS: Retrospective analysis of our patient cohort revealed 4 patients with enterobiliary anastomosis and Roux-en-Y entero-enteric anastomosis who underwent repeated ERC with DBE and SBE because of recurrent cholangitis.

RESULTS: A total of 38 endoscopic retrograde cholangiopancreatography procedures were performed in 25 patients with Roux-en-Y entero-enteric anastomosis. DBE was used in 29 procedures and SBE in 9. The 4 patients who underwent repeated ERC with DBE and SBE suffered from recurrent cholangitis due to stenosis of the enterobiliary anastomosis. ERC was performed repeatedly to achieve balloon dilation with/without biliary stone extraction and multiple stent placement at the level of the enterobiliary anastomosis. In all 4 patients DBE and SBE were equally successful. Compared to DBE, SBE was equally effective in passing the Roux-en-Y entero-enteric anastomosis, reaching the enterobiliary anastomosis and performing therapeutic ERC.

CONCLUSION: This retrospective comparison shows that DBE and SBE are equally successful in the performance of therapeutic ERC at the level of the enterobiliary anastomosis after Roux-en-Y entero-enteric anastomosis.

A single-institution experience with 491 cases of small bowel adenocarcinoma

BACKGROUND

The optimal treatment of small bowel adenocarcinoma is unknown.

METHODS

The records of 491 patients with small bowel adenocarcinoma diagnosis between 1970 and 2005 were reviewed for patient and tumor characteristics, treatment effects, and survival.

RESULTS

The median age at diagnosis was 62 years. The most common tumor locations were the duodenum (57%), jejunum (29%), and ileum (10%). The median overall survival was 20.1 months, with a 5-year overall survival of 26%. Greater age, male sex, higher stage and grade, residual disease after resection, and a lymph node ratio of 50% or greater predicted decreased overall survival in univariate analysis. Age and stage were predictive of survival in multivariate analysis. The overall survival with metastatic disease was poor. Adjuvant therapy was not associated with longer overall survival (P = .44).

CONCLUSIONS

The prognosis of patients with small bowel adenocarcinoma is poor. Complete resection provides the only means of cure, and the role for adjuvant therapy remains uncertain.

Exacerbation of indomethacin-induced small intestinal injuries in Reg I-knockout mice

Nonsteroidal anti-inflammatory drug (NSAID)-induced small intestinal injuries are serious clinical events and a successful therapeutic strategy is difficult. Regenerating gene (Reg) I protein functions as a regulator of cell proliferation and maintains intercellular integrity in the small intestine. The aim of this study was to evaluate the role of Reg I in NSAID-induced small intestinal injuries. First, to examine the effect of Reg I deficiency on such injuries, indomethacin, a widely used NSAID, was injected subcutaneously into 10-wk-old male Reg I-knockout (Reg I(-/-)) and wild-type (Reg I(+/+)) mice twice with an interval of 24 h, after which the mice were euthanized. Small intestinal injuries were assessed by gross findings, histopathology, and contents of IL-1beta and MPO in the experimental tissues. Next, we investigated the therapeutic potential of Reg I in indomethacin-induced small intestinal injuries. Recombinant Reg I protein (rReg I) was administered to 10-wk-old male ICR mice, then indomethacin was administered 6 h using the same protocol as noted above, after which small intestinal injuries were assessed after euthanasia. Our results showed that Reg I(-/-) mice had a greater number of severe small intestinal lesions after indomethacin administration. Histological examinations of the small intestines from those mice revealed deep ulcers with prominent inflammatory cell infiltration, whereas the mucosal content of proinflammatory agents was also significantly increased. In addition, rReg I administration inhibited indomethacin-induced small intestinal injuries in ICR mice. In conclusion, Reg I may be useful as a therapeutic agent in NSAID-induced small intestinal injuries.

Endoscopic management of biliary ductal stones

Bile duct stone management has greatly changed in the past 2 decades. Open surgical techniques have mostly been replaced by transoral endoscopic techniques. Routine common bile duct stones can be managed by standard biliary endoscopic sphincterotomy and extraction. Various advanced transoral techniques can also manage most difficult ductal stones. In skilled centers, laparoscopic ductal stone management has assumed a back-up role.

Double balloon enteroscopy and acute pancreatitis

Double balloon enteroscopy (DBE) is a new technique, first published and introduced into clinical practice in 2001 by Yamamoto, the inventor of this outstanding method. DBE allows complete visualization, biopsy and treatment of the small bowel. Nowadays, we have some experience of this method for evaluation of the complication rate. Severe complications are described in 1%-1.7% of patients. Acute pancreatitis is a rare complication of the investigation. The incidence of acute pancreatitis after diagnostic DBE is 0.3% in most studies. More than 50 cases of acute pancreatitis have been described in the literature so far. On the contrary, hyperamylasemia after DBE seems to be a rather common condition. Association with acute pancreatitis is supposed to be possible, but not obligatory. The causal mechanism of post-DBE acute pancreatitis is uncertain, and there are several theories in the literature. The most probable cause seems to be a mechanical straining of the endoscope with over-tube on the pancreas or in the papillary area.

Clinical outcome in patients with small-intestinal non-Hodgkin lymphoma

The clinical features and outcome of small intestinal lymphoma remain unclear. We retrospectively analyzed 23 patients who had non-Hodgkin lymphoma with a small intestinal lesion. With a median follow-up of 37 months, the 5-year overall survival and failure-free survival (FFS) were 64% and 60%, respectively. In a univariate analysis, a worse performance status at the start of treatment and the occurrence of abdominal symptoms or perforation during treatment were associated with poor survival. Perforation often resulted in a dismal prognosis in patients with uncontrollable lymphoma, but not in patients with lymphoma in remission. The role of surgery in small intestinal lymphoma remains equivocal. In the current study, surgery before other therapies favorably influenced FFS, and all patients who underwent complete resection of the small intestinal lesion had extremely favorable results. Further studies are warranted to establish optimal therapeutic strategies.

Present status and strategy of NSAIDs-induced small bowel injury

Non-steroidal anti-inflammatory drugs (NSAIDs) are well known to cause gastroduodenal mucosal lesions as an adverse effect. Recently, the serious problem of NSAID-induced small intestinal damage has become a topic of great interest to gastroenterologists, since capsule endoscopy and balloon enteroscopy are available for the detection of small intestinal lesions. Such lesions have been of great concern in clinical settings, and their treatment and prevention must be devised as soon as possible. The prevalence of NSAIDs-induced small intestinal injury is higher than had been expected. Recent studies show that more than 50% of patients taking NSAIDs have some mucosal damage in the small intestine. The gross appearance of NSAID-induced enteropathy varies, appearing variously as diaphragm-like strictures, ulcers, erosions, and mucosal redness. To investigate NSAID-induced enteropathy, and to rule out other specific enteropathies, other useful methods (in addition to capsule endoscopy and balloon enteroscopy) include such modalities as radiological examination of the small intestine, the permeability test, scintigraphy or the fecal excretion test using (111)Indium-labeled white blood cells, and measurement of the fecal calprotectin concentration. Diaphragm-like strictures and bleeding from mucosal breaks may be treatable with interventional enteroscopy. Misoprostol, metronidazole, and sulfasalazine are frequently used to treat NSAID-induced enteropathy, but have undesirable effects in some cases. In the experimental model, we confirmed that several existing drugs for gastroduodenal ulcers prevented indomethacin-induced small intestinal injury. Such drugs may be useful for preventing the adverse effects of NSAIDs not only in the stomach but also in the small intestine. We hope to examine these drugs in future clinical studies.

Balloon overtube-guided colorectal endoscopic submucosal dissection

AIM: To evaluate the usefulness of a balloon overtube to assist colorectal endoscopic submucosal dissection (ESD) using a gastroscope.

METHODS: The results of 45 consecutive patients who underwent colorectal ESD were analyzed in a single tertiary endoscopy center. In preoperative evaluation of access to the lesion, difficulties were experienced in the positioning and stabilization of a gastroscope in 15 patients who were thus assigned to the balloon-guided ESD group. A balloon overtube was placed with a gastroscope to provide an endoscopic channel to the lesion in cases with preoperatively identified difficulties related to accessibility. Colorectal ESD was performed following standard procedures. A submucosal fluid bleb was created with hyaluronic acid solution. A circumferential mucosal incision was made to marginate the lesion. The isolated lesion was finally excised from the deeper layers with repetitive electrosurgical dissections with needle knives. The success of colorectal ESD, procedural feasibility, and procedure-related complications were the main outcomes and measurements.

RESULTS: The overall en bloc excision rate of colorectal ESD during this study at our institution was 95.6%. En bloc excision of the lesion was successfully achieved in 13 of the 15 patients (86.7%) in the balloon overtube-guided colorectal ESD group, which was comparable to the results of the standard ESD group with better accessibility to the lesion (30/30, 100%, not statistically significant).

CONCLUSION: Use of a balloon overtube can improve access to the lesion and facilitate scope manipulation for colorectal ESD.

Peutz-Jeghers syndrome: Diagnostic and therapeutic approach

Peutz-Jeghers syndrome (PJS) is an inherited, autosomal dominant disorder distinguished by hamartomatous polyps in the gastrointestinal tract and pigmented mucocutaneous lesions. Prevalence of PJS is estimated from 1 in 8300 to 1 in 280 000 individuals. PJS predisposes sufferers to various malignancies (gastrointestinal, pancreatic, lung, breast, uterine, ovarian and testicular tumors). Bleeding, obstruction and intussusception are common complications in patients with PJS. Double balloon enteroscopy (DBE) allows examination and treatment of the small bowel. Polypectomy using DBE may obviate the need for repeated urgent operations and small bowel resection that leads to short bowel syndrome. Prophylaxis and polypectomy of the entire small bowel is the gold standard in PJS patients. Intraoperative enteroscopy (IOE) was the only possibility for endoscopic treatment of patients with PJS before the DBE era. Both DBE and IOE facilitate exploration and treatment of the small intestine. DBE is less invasive and more convenient for the patient. Both procedures are generally safe and useful. An overall recommendation for PJS patients includes not only gastrointestinal multiple polyp resolution, but also regular lifelong cancer screening (colonoscopy, upper endoscopy, computed tomography, magnetic resonance imaging or ultrasound of the pancreas, chest X-ray, mammography and pelvic examination with ultrasound in women, and testicular examination in men). Although the incidence of PJS is low, it is important for clinicians to recognize these disorders to prevent morbidity and mortality in these patients, and to perform presymptomatic testing in the first-degree relatives of PJS patients.

Technology and indications

Double-balloon endoscopy (DBE) was developed based on the principle of preventing stretching of the intestinal tract by anchoring the convoluted intestinal tract with an endoscope and overtube fitted with inflatable balloons. The DBE system includes the main body of the endoscope with a built-in air channel, a balloon attached to the tip of the endoscope, an overtube with a hydrophilic coating equipped with an inflatable balloon, and a balloon controller that safely inflates/deflates the two balloons. At present, there are three different types of endoscopes for DBE. The indications for DBE include the diagnosis or treatment of various small intestinal conditions such as obscure gastrointestinal bleeding, Crohn's disease, and benign and malignant tumors. In addition, DBE can be used to approach the surgically modified intestinal tract; conventional endoscopes have difficulty in that situation. DBE can be used for colonoscopy in cases in which it is difficult to insert a conventional colonoscope. In the future, DBE will have the potential for wider use in routine colonoscopy because the insertion technique is easy and reliable.