Obscure gastrointestinal bleeding

Enteroscopy versus Video Capsule Endoscopy for Automatic Diagnosis of Small Bowel Disorders-A Comparative Analysis of Artificial Intelligence Applications

BACKGROUND

Small bowel disorders present a diagnostic challenge due to the limited accessibility of the small intestine. Accurate diagnosis is made with the aid of specific procedures, like capsule endoscopy or double-ballon enteroscopy, but they are not usually solicited and not widely accessible. This study aims to assess and compare the diagnostic effectiveness of enteroscopy and video capsule endoscopy (VCE) when combined with artificial intelligence (AI) algorithms for the automatic detection of small bowel diseases.

MATERIALS AND METHODS

We performed an extensive literature search for relevant studies about AI applications capable of identifying small bowel disorders using enteroscopy and VCE, published between 2012 and 2023, employing PubMed, Cochrane Library, Google Scholar, Embase, Scopus, and ClinicalTrials.gov databases.

RESULTS

Our investigation discovered a total of 27 publications, out of which 21 studies assessed the application of VCE, while the remaining 6 articles analyzed the enteroscopy procedure. The included studies portrayed that both investigations, enhanced by AI, exhibited a high level of diagnostic accuracy. Enteroscopy demonstrated superior diagnostic capability, providing precise identification of small bowel pathologies with the added advantage of enabling immediate therapeutic intervention. The choice between these modalities should be guided by clinical context, patient preference, and resource availability. Studies with larger sample sizes and prospective designs are warranted to validate these results and optimize the integration of AI in small bowel diagnostics.

CONCLUSIONS

The current analysis demonstrates that both enteroscopy and VCE with AI augmentation exhibit comparable diagnostic performance for the automatic detection of small bowel disorders.

Efficacy and safety of double- versus single-balloon retrograde enteroscopy

INTRODUCTION

Data on the safety and efficacy of double-balloon enteroscopy (DBE) and single-balloon enteroscopy (SBE) are conflicting. We aimed to compare the efficacy and safety of retrograde DBE to SBE.

METHODS

We performed a retrospective analysis of all patients who underwent retrograde DBE or SBE at a large tertiary referral center from 2008 to December 2018. Outcomes assessed included technical success, diagnostic yield, therapeutics, depth of insertion, and procedural duration.

RESULTS

A total of 523 (403 DBE, 120 SBE) patients underwent retrograde enteroscopy during the study period. The mean age was 59.4 ± 17.24 and 59.57 ± 16.94 years in DBE and SBE groups, respectively. There was no difference in technical success (91.0% vs. 92.5%, P = 0.85), diagnostic yield (40.9% vs. 40.8%, P = 0.95), and therapeutics (17.1% vs. 19.1%, P = 0.61) between DBE and SBE. Compared to SBE, DBE had significantly shorter mean procedure time (26.5 ± 34.5 min vs. 34.8 ± 29.4 min, P = 0.01) and higher maximal depth of insertion from ileocecal valve (108.1 ± 84.1 cm vs. 73.3 ± 63.4 cm, P = 0.001). Safety events were rare and similar in both groups.

CONCLUSION

Retrograde DBE is associated with a significantly higher depth of insertion and shorter procedural duration, but similar diagnostic yield and technical success compared to SBE.

Clinical Outcomes of Negative Balloon-Assisted Enteroscopy for Obscure Gastrointestinal Bleeding: A Systematic Review and Meta-Analysis

Background

For patients with obscure gastrointestinal bleeding (OGIB), finding the bleeding site is challenging. Balloon-assisted enteroscopy (BAE) has become the preferred diagnostic modality for OGIB. The long-term outcome of patients with negative BAE remains undefined. The present study aimed to evaluate the long-term outcomes of patients with negative BAE results for OGIB and to clarify the effect of further investigations at the time of rebleeding with a systematic review and meta-analysis of the available cohort studies.

Methods

Studies were searched through the PubMed, EMBASE, and Cochrane library databases. The following indexes were analyzed: rebleeding rate after negative BAE, rebleeding rate after different follow-up periods, the proportion of patients who underwent further evaluation after rebleeding, the percentage of patients with identified rebleeding sources, and the percentage of patients with rebleeding sources in the small intestine. Heterogeneity was assessed using the I² test.

Results

Twelve studies that involved a total of 407 patients were included in the analysis. The pooled rebleeding rate after negative BAE for OGIB was 29.1% (95% CI: 17.2–42.6%). Heterogeneity was significant among the studies (I² = 88%; p < 0.0001). The Chi-squared test did not show a difference in rebleeding rates between the short and long follow-up period groups (p = 0.142). The pooled proportion of patients who underwent further evaluation after rebleeding was 86.1%. Among the patients who underwent further evaluation, rebleeding sources were identified in 73.6% of patients, and 68.8% of the identified rebleeding lesions were in the small intestine.

Conclusion

A negative result of BAE in patients with OGIB indicates a subsequently low risk of rebleeding. Further evaluation should be considered after rebleeding.

Obscure Gastrointestinal Bleeding Due to Non-steroidal Anti-inflammatory Drug-Induced Colopathy

Obscure gastrointestinal (GI) bleeding poses a diagnostic challenge and is associated with high mortality. We report a case of life-threatening obscure GI bleeding precipitated by the ingestion of a non-steroidal anti-inflammatory drug (NSAID). The source of bleeding could not be identified preoperatively, and hence exploratory laparotomy was performed. An ileocaecal resection was undertaken based on the findings of the intraoperative enteroscopy. However, the bleeding recurred and repeated endoscopy examination identified the source to be multiple NSAID-induced ulcers that were scattered in the colo-rectum. The bleeding stopped spontaneously after a period of intensive supportive therapy and sulphasalazine enemas. This case highlights the diagnostic challenge of obscure GI bleeding. It also highlights the potentially life-threatening danger of GI bleeding secondary to NSAID-induced colopathy, even after a short course of treatment.

Diagnostic Yields and Clinical Impacts of Capsule Endoscopy

Observing the entire small bowel is difficult due to the presence of complex loops and a long length. Capsule endoscopy (CE) provides a noninvasive and patient-friendly method for visualizing the small bowel and colon. Small bowel capsule endoscopy (SBCE) has a critical role in the diagnosis of small bowel disorders through the direct observation of the entire small bowel mucosa and is becoming the primary diagnostic tool for small bowel diseases. Recently, colon capsule endoscopy (CCE) was also considered safe and feasible for obtaining sufficient colonic images in patients with incomplete colonoscopy, in the absence of bowel obstruction. This review article assesses the current status of CE in terms of the diagnostic yield and the clinical impact of SBCE in patients with obscure gastrointestinal bleeding, who have known or suspected Crohn's disease, small bowel tumor and inherited polyposis syndrome, celiac disease, and those who have undergone CCE.

Provocative Angiography, Followed by Therapeutic Interventions, in the Management of Hard-To-Diagnose Gastrointestinal Bleeding

BACKGROUND

Despite significant advances in imaging and endoscopic diagnostic techniques, adequate localization of gastrointestinal bleeding (GIB) can be challenging. Provocative angiography (PROVANGIO) has not been part of the standard diagnostic algorithms yet. We sought to examine the ability of PROVANGIO to identify the bleeding source when conventional radiography fails.

METHODS

Patients undergoing PROVANGIO for GIB during 2008-2014 were retrospectively included. Demographics and periprocedural patient characteristics were recorded. PROVANGIO was performed in a multidisciplinary setting, involving interventional radiology, surgery and anesthesiology teams, ready to intervene in case of uncontrolled bleeding. The procedure included conventional angiography of the celiac, superior and inferior mesenteric arteries (SMA, IMA) followed by a stepwise bleeding provocation with anticoagulating, vasodilating and/or thrombolytic agent administration, combined with angiography.

RESULTS

Twenty-three PROVANGIO were performed. Patients were predominantly male (15, 65.2%), and hematochezia was the most common presenting symptom (12, 52.2%). Patients with a positive PROVANGIO had lower Charlson comorbidity index (1 vs. 7, p = 0.009) and were less likely to have a prior history of GIB (14.3% vs. 87.5%, p = 0.001). PROVANGIO localized bleeding in 7 (30%) patients. In 6 out of 7 patients, the bleeding source was identified in the SMA and, in one case, in the IMA distribution. The bleeding was controlled angiographically in four cases, endoscopically in one case and surgically in the remaining two. No complications related to PROVANGIO were detected.

CONCLUSIONS

In our series, PROVANGIO safely identified the bleeding source, and provided that necessary safeguards are put into place, we recommend incorporating it in the diagnostic algorithms for GIB management.

Non-variceal gastrointestinal bleed in children: surgical experience with emphasis on management challenges

PURPOSE

This exclusively surgical series on pediatric non-variceal gastrointestinal bleed (NVGIB) defines three levels of bleed site and describes etiology, bleed severity, diagnostic algorithm, and surgical management for each bleed site. Management challenges are detailed.

METHODS

Patients aged ≤ 18 years treated surgically for NVGIB were analysed.

RESULTS

Bleed site (n = 87) was classified as: upper gastrointestinal bleed (UGIB; n = 11); small bowel bleed (SBB: n = 52); and lower GIB (n = 24). Four etiology-based groups were identified: lesions with ectopic gastric mucosa (EGM; n = 33), tumours (n = 23), ulcers (n = 21), and vascular pathology (n = 8). Bleed severity spectrum was: acute severe bleed (n = 12); subacute overt bleed (n = 59); and occult GIB (n = 16). Preoperative diagnosis was obtained in all UGIB and LGIB lesions. Eighty-two percent of surgical SB lesions were diagnosed preoperatively on Tc^99m pertechnetate scan, computed tomography enterography-angiography, and capsule endoscopy; remaining 18% were diagnosed at laparotomy with intra-operative enteroscopy (IOE). Surgical management was tailored to bleed site, severity, and etiology. Indications of IOE and approach to management challenges are detailed.

CONCLUSIONS

The commonest site-specific bleed etiologies were duodenal ulcers for UGIB, EGM lesions for SBB, and tumours for LGIB. SBB presented diagnostic challenge. Diagnostic algorithm was tailored to bleed site, age-specific etiology, bleed severity, and associated abdominal/systemic symptoms. Management challenges were acute severe bleed, occult GIB, SBB, obscure GIB, and rare etiologies. IOE has a useful role in SBB management.

Arterioportal fistula after partial gastrectomy treated with coil embolisation

Arterioportal fistulas are a rare complication of abdominal interventions. They can remain asymptomatic for a long time and manifest with symptoms of portal hypertension. We present the case of a 65-year-old man admitted to the emergency room with increasing fatigue and melena. He had a history of partial gastrectomy with Billroth II reconstruction 40 years earlier for peptic ulcer perforation. On physical examination, he was pale and presented a machinery-type murmur in the epigastric area. Blood tests revealed iron deficiency anaemia of 5.6 g/dL. During hospitalisation, he required several blood transfusions and maintained melenas. An abdominal CT angiography showed a fusiform aneurysm of the left gastric artery draining to the venous portal-splenic confluent. He was successfully treated with transarterial coil embolisation of the left gastric artery aneurysm. The correct diagnosis of arterioportal fistulas can be very challenging, whereas the standard treatment with coil embolisation offers a low morbidity resolution of symptoms.

Role of endoscopy in acute gastrointestinal bleeding in real clinical practice: An evidence-based review

Although upper gastrointestinal bleeding is usually segregated from lower gastrointestinal bleeding, and guidelines for gastrointestinal bleeding are divided into two separate sections, they may not be distinguished from each other in clinical practice. Most patients are first observed with signs of bleeding such as hematemesis, melena, and hematochezia. When a patient with these symptoms presents to the emergency room, endoscopic diagnosis and treatment are considered together with appropriate initial resuscitation. Especially, in cases of variceal bleeding, it is important for the prognosis that the endoscopy is performed immediately after the patient stabilizes. In cases of suspected lower gastrointestinal bleeding, full colonoscopy after bowel preparation is effective in distinguishing the cause of the bleeding and treating with hemostasis. The therapeutic aspect of endoscopy, using the mechanical method alone or injection with a certain modality rather than injection alone, can increase the success rate of bleeding control. Therefore, it is important to consider the origin of bleeding and how to approach it. In this article, we aim to review the role of endoscopy in diagnosis, treatment, and prognosis in patients with acute gastrointestinal bleeding in a real clinical setting.

Double-balloon enteroscopy (DBE) in patients presenting with obscure gastrointestinal bleeding (OGIB)

BACKGROUND AND STUDY AIMS

Obscure gastrointestinal bleeding (OGIB) is defined as bleeding of unknown origin that persists or recurs after an initial negative investigation. Identifying the source of OGIB represents a diagnostic challenge that is frequently focused on visualizing the small intestine. Conventional diagnostic methods, such as push enteroscopy, small-bowel follow-through, radionuclide scanning, and angiography, each exhibit inherent limitations. Double balloon enteroscopy (DBE) was designed specifically to evaluate the entire small bowel. DBE allows for better visualization, biopsy of the identified lesions and application of therapeutic techniques. This study sought to assess the role of DBE in the diagnosis and management of patients with OGIB.

PATIENTS AND METHODS

This prospective study was conducted to analyse data from 31 patients presenting with OGIB referred for DBE in the Endoscopy Unit at the Internal Medicine Department of the Faculty of Medicine, Cairo University.

RESULTS

Five patients had lesions in locations other than the small intestine that accounted for GI bleeding. Thus, the potential source of OGIB was defined as the small intestine in 18 of 26 patients (69.2%), and negative DBE findings were noted in eight patients (30.8%). Major findings included small intestinal tumours in eight patients, vascular bleeding lesions in 8 patients and ulcerations in 2 patients. Endoscopic haemostasis was performed in eight patients with vascular lesions. The three patients with Petuz-Jegher syndrome underwent polypectomy of their major polyps. Patients with gastrointestinal tumours were referred for surgery.

CONCLUSION

DBE is an excellent endoscopic procedure that has a relatively high diagnostic and therapeutic yield. The procedure is feasible and exhibits a high safety profile with a low complication rate when performed by an experienced endoscopist.

Optimal Diagnostic Approaches for Patients with Suspected Small Bowel Disease

While the domain of gastrointestinal endoscopy has made great strides over the last several decades, endoscopic assessment of the small bowel continues to be challenging. Recently, with the development of new technology including video capsule endoscopy, device-assisted enteroscopy, and computed tomography/magnetic resonance enterography, a more thorough investigation of the small bowel is possible. In this article, we review the systematic approach for patients with suspected small bowel disease based on these advanced endoscopic and imaging systems.

Gastrointestinal hemorrhage: evaluation with MDCT

Gastrointestinal (GI) bleeding is a common medical problem, with high associated morbidity and mortality. The clinical presentation of gastrointestinal hemorrhage varies with the location of the bleeding source, the intensity of the bleed, and the presence of comorbidities that affect the ability to tolerate blood loss. Conventional endoscopic examinations are usually the initial diagnostic tests in patients presenting with overt gastrointestinal hemorrhage. However, implementation of upper tract endoscopy and colonoscopy in the emergency setting can be challenging due to inconsistent availability of the service and difficulties in achieving adequate colonic cleansing in emergent situations. Thus, imaging tests are often relied upon to establish the location and the cause of bleeding, either for initial diagnosis or after non-revealing upper and lower tract endoscopies ("obscure" bleeding). This article discusses the imaging evaluation of patients with gastrointestinal bleeding and reviews the imaging appearance of the most common causes, taking into account the two most relevant clinical presentations: overt bleeding and obscure bleeding.

The Role of Capsule Endoscopy in Patients with Obscure Gastrointestinal Bleeding

Obscure gastrointestinal bleeding (OGIB) accounts for 5% of all gastrointestinal (GI) bleeding cases and is often caused by small bowel lesions. Capsule endoscopy (CE), which allows non-invasive visualization of the small bowel mucosa, has revolutionized the evaluation of OGIB. CE is preferred by both patients and physicians mainly because of its non-invasiveness, and is widely used as the first-line diagnostic modality for OGIB. The diagnostic yield of CE in OGIB has been reported to be in the range of 32% to 83%. Although no direct comparison has been made, a meta-analysis showed similar diagnostic yields between CE and double-balloon enteroscopy (DBE) for OGIB. However, CE could enhance the yield of subsequent DBE and serve as a guide for optimizing the insertion route for DBE. Even after negative CE, selected patients could benefit from second-look CE for OGIB. In terms of outcomes, a favorable clinical impact after CE has been reported in several studies. However, observations indicate that CE might not influence clinical outcomes directly, but rather play a role in selecting patients with OGIB who are likely to benefit from subsequent evaluation and intervention.

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.

Evaluation and outcomes of patients with obscure gastrointestinal bleeding

Obscure gastrointestinal bleeding (OGIB) is defined as recurrent or persistent bleeding or presence of iron deficiency anaemia after evaluation with a negative bidirectional endoscopy. OGIB accounts for 5% of gastrointestinal bleeding and presents a diagnostic challenge. Current modalities available for the investigation of OGIB include capsule endoscopy, balloon assisted enteroscopy, spiral enteroscopy and computed tomography enterography. These modalities overcome the limitations of previous techniques. Following a negative bidirectional endoscopy, capsule endoscopy and double balloon enteroscopy remain the cornerstone of investigation in OGIB given their high diagnostic yield. Long-term outcome data in patients with OGIB is limited, but is most promising for capsule endoscopy. This article reviews the current literature and provides an overview of the clinical evaluation of patients with OGIB, available diagnostic and therapeutic modalities and long-term clinical outcomes.

Obscure gastrointestinal bleeding: single centre experience of capsule endoscopy

The advent of capsule endoscopy (CE) has resulted in a paradigm shift in the approach to the diagnosis and management of patients with obscure gastrointestinal bleeding (OGIB). With increasing global availability of this diagnostic tool, it has now become an integral part of the diagnostic algorithm for OGIB in most parts of the world. However, there is scant data on optimum timing of CE for maximizing diagnostic yield. OGIB continues to be a challenge because of delay in diagnosis and consequent morbidity and mortality. We evaluated the diagnostic yield of CE in identifying the source of bleeding in patients with OGIB. We identified patients who underwent CE at our institution from May 2006 to May 2011. The patients' medical records were reviewed to determine the type of OGIB (occult, overt), CE results and complications, and timing of CE with respect to onset of bleeding. Out of 346 patients investigated for OGIB, 246 (71.1%) had some lesion detected by CE. In 206 patients (59.5%), definite lesions were detected that could unequivocally explain the OGIB. Small bowel angiodysplasia, ulcer/erosions secondary to Crohn's disease, non-steroidal anti-inflammatory agent use, and neoplasms were the commonest lesions detected. Visualization of the entire small bowel was achieved in 311 (89.9%) of cases. Capsule retention was noted in five patients (1.4%). In this study, CE was proven to be a safe, comfortable, and effective, with a high rate of accuracy for diagnosing OGIB.

Meckel’s diverticulum bleeding diagnosed with magnetic resonance enterography: A case report

Although the introduction of double-balloon enteroscopy has greatly improved the diagnostic rate, definite diagnosis of Meckel’s diverticulum far from the ileocecal valve is still impossible in most cases. We explored the role of magnetic resonance (MR) enterography in detecting bleeding from Meckel’s diverticulum that can not be confirmed via double-balloon enteroscopy. This study describes a case of male patient with bleeding from Meckel’s diverticulum diagnosed with MR enterography of the small intestine. No bleeding lesion was found via colonoscopy, anal enteroscopy, or oral colonoscopy. MR enterography of the small intestine revealed an occupying lesion of 3.0 cm in the lower segment of the ileum. The patient was transferred to the Department of Abdominal Surgery of our hospital for surgical treatment. During surgery, a mass of 3 cm × 2 cm was found 150 cm from the ileocecal valve, in conjunction with congestion and edema of the corresponding mesangium. Intraoperative diagnosis was small bowel diverticulum with bleeding. The patient underwent partial resection of the small intestine. Postoperative pathology showed Meckel’s diverticulum containing pancreatic tissues. He was cured and discharged 7 d after operation. We conclude that MR enterography of the small intestine has greatly improved the diagnosis rate of Meckel’s diverticulum, particularly in those patients with the disease which can not be confirmed via double-balloon enteroscopy.

The American Society for Gastrointestinal Endoscopy (ASGE) diagnostic algorithm for obscure gastrointestinal bleeding: eight burning questions from everyday clinical practice

The diagnosis and management of patients with obscure gastrointestinal bleeding are often long and challenging processes. Over the last 10 years the introduction in clinical practice of new diagnostic and therapeutic procedures (i.e. Capsule Endoscopy, Computed Tomographic Enterography, Magnetic Resonance Enterography, and Device Assisted Enteroscopy) has revolutionized the diagnostic/therapeutic work-up of these patients. Based on evidence published in the last 10 years, international scientific societies have proposed new practice guidelines for the management of obscure gastrointestinal bleeding, which include these techniques. However, although these algorithms (the most recent ones are endorsed by the American Society for Gastrointestinal Endoscopy - ASGE) allow the management of the large majority of patients, some issues still remain unsolved. The present paper reports the results of the discussion, based on the literature published up to September 2011, among a panel of experts and gastroenterologists, working with Capsule Endoscopy and with Device Assisted Enteroscopy, attending the 6th annual meeting of the Italian Club for Capsule Endoscopy and Enteroscopy. Eight unresolved issues were selected: each of them is presented as a "Burning question" and the "Answer" is the strategy proposed to manage it, according to both the available evidence and the discussion among participants.

CT enterography in obscure gastrointestinal bleeding: a systematic review and meta-analysis

The objective of this article is to provide a comprehensive and update overview of clinical application of CT enterography (CTE) in the evaluation of obscure gastrointestinal bleeding (OGIB). We performed a systematic review of relevant literatures in PubMed, EMBASE and The Cochrane Library and pooled the yield of CTE and the incremental yield (IY) of CTE over an alternate modality. A total of 18 studies (n = 660) reported the yield of CTE in evaluating OGIB and the pooled yield was 40% (95% confidence interval (CI): 33-49%). Seven studies (n = 279) compared the yield of CTE with capsule endoscopy (CE). The yield for CTE and CE for all findings was 34% and 53%, respectively (IY = -19%, 95% CI = -34% to -4%). When considering the types of identified lesions, the yield was significantly different for vascular and inflammatory lesions but not significantly different for neoplastic or other lesions. Two studies (n = 63) compared the yield of CTE with double-balloon enteroscopy (DBE). The yield for CTE and DBE was 38% and 78%, respectively (IY = -40%, 95% CI = -55% to -25%). Three studies (n = 49) compared the yield of CTE with digital subtraction angiography. The yield for CTE and digital subtraction angiography was 64% and 60%, respectively (IY = 4%, 95% CI = -40% to 47%). CTE is an excellent diagnostic tool in patients with OGIB. It may play a complementary role to CE and can be used as a triage tool prior to DBE in evaluating OGIB.

Endoscopic and radiographic evaluation of the small bowel in 2012

Traditionally, the diagnosis of small bowel disorders has been challenging secondary to the small intestine's length, tortuosity, and anatomic location. Recent technologic advancements in the field of enteroscopy and radiographic imaging have facilitated a more thorough endoscopic evaluation of patients with small bowel disease ranging from obscure gastrointestinal bleeding to inflammatory bowel disease and small bowel tumors. Such developments have made it possible to avoid invasive surgical procedures in certain clinical scenarios where they were previously the gold standard. In this review, we report an update on the diagnostic and management approach to patients with small bowel disease, emphasizing the advantages and limitations of the latest modalities now available to primary care physicians and gastroenterologists for evaluating patients with presumed disease of the small intestine.

Obscure and occult gastrointestinal bleeding: comparison of different imaging modalities

Patients with persistent, recurrent, or intermittent bleeding from the gastrointestinal (GI) tract for which no definite cause has been identified by initial esophagogastroduodenoscopy, colonoscopy, or conventional radiologic evaluation are considered to have an obscure GI bleeding (OGIB). The diagnosis and management of patients with OGIB is challenging, often requiring extensive and expensive workups. The main objective is the identification of the etiology and site of bleeding, which should be as rapidly accomplished as possible, in order to establish the most appropriate therapy. The introduction of capsule endoscopy and double balloon enteroscopy and the recent improvements in CT and MRI techniques have revolutionized the approach to patients with OGIB, allowing the visualization of the entire GI tract, particularly the small bowel, until now considered as the "dark continent" . In this article we review and compare the radiologic and endoscopic examinations currently used in occult and OGIB, focusing on diagnostic patterns, pitfalls, strengths, weaknesses, and value in patients' management.

64-section multiphase CT enterography as a diagnostic tool in the evaluation of obscure gastrointestinal bleeding

BACKGROUND AND AIM

Small bowel follow through (SBFT) and enteroclysis have low sensitivity in picking up lesions in obscure gastrointestinal bleed (OGIB). Computed tomographic enterography (CT-EG), performed with 64-slice multiphase CT system by using large volumes of ingested neutral enteric contrast material, has high spatial and temporal resolution in visualization of the small bowel wall and lumen. The role of 64-slice multiphase CT-EG in the evaluation of OGIB is still evolving, and data on this role are scarce. We evaluated the efficacy of 64-slice multiphase CT-EG using polyethylene glycol (PEG) electrolyte solution as neutral contrast in patients of OGIB.

METHODS

CT-EG was performed with 64-slice multiphase CT system using large volume (2,000 mL) of PEG electrolyte solution as oral contrast in patients of OGIB.

RESULTS

Thirty-five patients (21 men, age 41.4 [13.5] y, range 19-70 year) with OGIB underwent CT-EG; 20 patients had overt OGIB whereas 15 patients had occult OGIB. Among 15 patients with occult OGIB, 10 patients had iron deficiency anemia (IDA) with fecal occult blood test (FOBT) positive and 5 had IDA with FOBT negative. Thirty-two patients (92 %) completed the procedure successfully. The total time taken for the ingestion of 2,000 mL of PEG electrolyte solution was median 64 (range 60-78) minutes. Adequate luminal distension of small bowel was seen in 29 (90.6 %) patients for successful interpretation of radiological images. Fifteen of 32 (46.9 %) patients had positive findings on CT-EG; 12 of them underwent exploratory laparotomy. The surgical findings were in conformity with CT-EG findings in all patients, which included gastrointestinal stromal tumors (GIST; n = 6), carcinoid (1), Meckel's diverticulum (1), small bowel adenocarcinoma (2) and jejunal vascular malformation (2).

CONCLUSION

64-slice multiphase CT-EG is a useful investigation in the evaluation of both occult and overt OGIB.

Roux-en-Y loop varices in children with portal hypertension after liver transplantation: an unusual cause of "obscure" gastrointestinal bleeding

PHALT may result from graft dysfunction, portal vein thrombosis, arterio-venous fistulas and can lead to GIB, commonly from bleeding esophageal varices. We present three children with GIB requiring multiple blood transfusions that were diagnosed with RY Loop bleeding. Routine EGD, colonoscopy, and CE failed to reveal the bleeding source. However, enteroscopy revealed large varices at the site of hepaticojejunostomy anastomosis in all. Our experience demonstrates that RY loop varices in children with PHALT are a rare and treatable cause of obscure GI bleeding.

Bleeding lesions within reach of conventional endoscopy in capsule endoscopy examinations for obscure gastrointestinal bleeding: is repeating endoscopy economically feasible?

BACKGROUND

Most tertiary gastroenterology centers currently offer an open-access capsule endoscopy (CE) service, including patients with obscure gastrointestinal bleeding. However, CE may identify lesions missed by conventional endoscopy.

AIMS

To determine the incidence of bleeding lesions missed by the preceding gastroscopy/colonoscopy that were revealed by CE and compare potential differences in the rate of identifying such lesions in patients that we investigated as opposed to those investigated elsewhere.

METHODS

We prospectively reviewed data from patients subjected to CE for obscure bleeding. We analyzed all cases where a source of bleeding was located in the stomach, duodenum, or colon.

RESULTS

A total of 317 consecutive patients were subjected to CE for obscure gastrointestinal bleeding within 28 months. Prior to CE examination, 174 patients had gastroscopy and colonoscopy in our institutions and 143 were referrals, all with negative endoscopic investigation. We identified 11 (3.5%) cases where the source of bleeding was found in the stomach (n = 4) or the cecum (n = 7). There was a significant difference of extra small intestinal lesions diagnosed by CE between referrals (9/143, 6.3%) and endoscopic investigation performed in our institutions (2/174, 1.15%), (p = 0.026). The estimated cost of re-endoscoping in our institution all CE referrals would be 50,050 euro (143 patients × 350 euro), to avoid unnecessary CE examinations (9 patients × 600 euro = 5,400 euro).

CONCLUSIONS

Reading the whole CE video is important, because small-bowel CE may identify lesions responsible for obscure bleeding missed by the preceding gastroscopy and colonoscopy. Repeating conventional endoscopy by experts before CE is not a cost-effective approach.

Obscure gastrointestinal bleeding: diagnostic performance of multidetector CT enterography

PURPOSE

To evaluate the diagnostic performance of computed tomographic (CT) enterography in identifying the source of obscure gastrointestinal bleeding and to determine clinical features associated with a higher diagnostic yield of CT enterography.

MATERIALS AND METHODS

The institutional review board approved this study, with waiver of informed consent. CT enterographic images in 65 patients (46 men [mean age, 54 years; range, 18-85 years] and 19 women [mean age, 62.1 years; range, 33-79 years]) who presented with obscure gastrointestinal bleeding between August 2005 and July 2007 were reviewed retrospectively and independently by two radiologists. The diagnostic performance of CT enterography was assessed by using the results of endoscopic and other imaging examinations, surgery, and clinical follow-up as the reference standard. Differences in the diagnostic yield of CT enterography according to patient demographic and clinical features, including age, sex, type and episode of bleeding (occult, initial overt, and recurrent overt), occurrence of recent bleeding, and history of massive bleeding, were evaluated by using univariate and multivariate logistic regression analyses.

RESULTS

CT enterography helped identify the source of obscure gastrointestinal bleeding in 16 (24.6%) of 65 patients. The sensitivity, specificity, positive predictive value, and negative predictive value of CT enterography were 55.2% (16 of 29), 100% (32 of 32), 100% (16 of 16), and 71.1% (32 of 45), respectively. Among patients' clinical features, a history of massive bleeding (diagnostic yield, 58.3% [seven of 12]; adjusted odds ratio, 7.2; P = .01) was independently associated with a higher diagnostic yield for CT enterography.

CONCLUSION

CT enterography has a potential role in the evaluation of obscure gastrointestinal bleeding. Despite the limited sensitivity of CT enterography, positive CT enterographic findings can reliably indicate the true source of obscure gastrointestinal bleeding. CT enterography is particularly effective in helping identify the source of bleeding in patients with a history of massive bleeding.

SUPPLEMENTAL MATERIAL

http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.11101936/-/DC1.

The role of endoscopic imaging of the small bowel in clinical practice

Enteroscopy, defined as direct visualization of the small bowel (SB) with the use of a fiberoptic or wireless endoscope, has progressed considerably over the past several years. Technological advancements in the field have facilitated endoscopic evaluation of the SB. This comprehensive clinical review summarizes the latest modalities available to aid gastroenterologists in exploring the SB for evaluation of obscure gastrointestinal bleeding, tumors, inflammatory bowel disease, and celiac disease. Previous physical limitations in equipment that made a complete evaluation of the SB difficult have all but disappeared with the advent of capsule endoscopy, balloon-assisted enteroscopy, and spiral enteroscopy.

Duodenal and jejunal varices due to superior mesenteric vein thrombosis presenting as a massive gastrointestinal tract bleeding: a case report

Duodenal and jejunal varices usually occur due to portal hypertension and are rare causes of gastrointestinal tract bleeding. We report the case of a patient with no clinically significant history of a coagulopathy disorder, cirrhosis, or portal hypertension who presented with duodenal and jejunal varices that resulted in lower gastrointestinal bleeding with superior mesenteric vein thrombosis. Mesenteric angiography revealed superior mesenteric vein thrombosis and varices at the fourth part of the duodenum and the proximal jejunum draining into the main portal vein, but no active bleeding source was recognized. The patient was hemodynamically unstable. Emergency laparotomy was performed and revealed duodenal and jejunal varices, with occlusion of the superior mesenteric vein. Partial resection of the duodenum and jejunum and end-to-end anastomosis were performed. After surgery, the patient was hemodynamically stable with no recurrence of bleeding.

Usefulness of CT angiography in diagnosing acute gastrointestinal bleeding: A meta-analysis

AIM: To analyze the accuracy of computed tomography (CT) angiography in the diagnosis of acute gastrointestinal (GI) bleeding.

METHODS: The MEDLINE, EMBASE, Cancerlit, Cochrane Library database, Sciencedirect, Springerlink and Scopus, from January 1995 to December 2009, were searched for studies evaluating the accuracy of CT angiography in diagnosing acute GI bleeding. Studies were included if they compared CT angiography to a reference standard of upper GI endoscopy, colonoscopy, angiography or surgery in the diagnosis of acute GI bleeding. Meta-analysis methods were used to pool sensitivity and specificity and to construct summary receiver-operating characteristic.

RESULTS: A total of 9 studies with 198 patients were included in this meta-analysis. Data were used to form 2 × 2 tables. CT angiography showed pooled sensitivity of 89% (95% CI: 82%-94%) and specificity of 85% (95% CI: 74%-92%), without showing significant heterogeneity (χ² = 12.5, P = 0.13) and (χ² = 22.95, P = 0.003), respectively. Summary receiver operating characteristic analysis showed an area under the curve of 0.9297.

CONCLUSION: CT angiography is an accurate, cost-effective tool in the diagnosis of acute GI bleeding and can show the precise location of bleeding, thereby directing further management.

The clinical utility of single-balloon enteroscopy: a single-center experience of 172 procedures

BACKGROUND

Single-balloon enteroscopy (SBE) is a novel endoscopic technique designed to evaluate and treat small-bowel disease. Although there is substantial literature addressing double-balloon enteroscopy and its impact on the diagnosis and management of small-bowel disease, there are limited data available on the clinical utility of SBE.

OBJECTIVES

To evaluate the clinical utility and diagnostic impact of SBE in a large cohort of patients at a single tertiary center.

DESIGN

Single-center, retrospective study.

SETTING

Digestive Disease Institute, Cleveland Clinic, Cleveland, Ohio.

PATIENTS

A total of 161 patients were referred for SBE from January 2006 to August 2008.

MAIN OUTCOME MEASUREMENTS

Demographic, clinical, procedural, and outcome data were collected and analyzed.

RESULTS

A total of 161 patients underwent a total of 172 procedures. Antegrade and retrograde approaches were used in 83% and 17% of subjects, respectively. The average insertion depth using the antegrade approach was 132 cm beyond the ligament of Treitz (range 20-400 cm). The average insertion depth using the retrograde approach was 73 cm above the ileocecal valve (range 10-160 cm). The average procedure time was 40 minutes overall, 38 minutes (range 12-90) antegrade and 48 minutes (range 28-89) retrograde. Fluoroscopy was used in 20 cases (12%). Diagnostic yield was 58% (99/172); 42% (72/172) were therapeutic cases. There were no significant complications.

LIMITATIONS

Single-center, retrospective study.

CONCLUSIONS

SBE demonstrated a high diagnostic yield and frequently provided useful therapeutic intervention. It seems to be a safe and effective method for performing deep enteroscopy.

Occult and obscure gastrointestinal bleeding: causes and clinical management

Occult gastrointestinal bleeding, defined as bleeding that is unknown to the patient, is the most common form of gastrointestinal bleeding and can be caused by virtually any lesion in the gastrointestinal tract. Patients with occult gastrointestinal bleeding include those with fecal occult blood and iron-deficiency anemia (IDA). In men and postmenopausal women, IDA should be considered to be the result of gastrointestinal bleeding until proven otherwise. Indeed, the possibility of gastrointestinal tract malignancy in these patients means that gastrointestinal evaluation is nearly always indicated. Obscure gastrointestinal bleeding is defined as obvious bleeding from a difficult to identify source and is always recurrent. This form of bleeding accounts for approximately 5% of all cases of clinically evident gastrointestinal bleeding and is most commonly caused by bleeding from the small intestine. Capsule endoscopy and deep enteroscopy have had a major impact on the way that patients with occult and, in particular, obscure bleeding are managed. In this Review the causes, diagnostic evaluation and treatment of occult and obscure gastrointestinal bleeding are discussed.

Preliminary estimate of triphasic CT enterography performance in hemodynamically stable patients with suspected gastrointestinal bleeding

OBJECTIVE

The objective of our study was to retrospectively evaluate the performance of triphasic CT enterography and identify causes of false-negative CT results in hemodynamically stable patients with suspected gastrointestinal bleeding.

MATERIALS AND METHODS

A retrospective review of 48 patients (male-female ratio, 22:26) with suspected gastrointestinal bleeding (first-episode gastrointestinal bleed, n = 19; obscure gastrointestinal bleed, n = 29) who underwent triphasic CT enterography was performed. All patients had endoscopic, pathologic, or other imaging confirmation within 3 months of triphasic CT enterography. The sensitivity and specificity of triphasic CT enterography were calculated using pathology, endoscopy, or other imaging confirmation as the reference standard. Results were retrospectively reviewed to determine the cause of missed findings at triphasic CT enterography.

RESULTS

The overall sensitivity and specificity of triphasic CT enterography for detecting gastrointestinal bleeding was 33% (7/21) and 89% (24/27), respectively. Sensitivity and specificity were higher in first-episode gastrointestinal bleed cases (42% and 100%, respectively) than in obscure gastrointestinal bleed cases (22% and 85%). In the subset of patients undergoing capsule endoscopy (n = 17), only triphasic CT enterography identified two of three bleeding sources. Triphasic CT enterography did not identify six ulcers, four vascular malformations, two hemorrhoids, a duodenal mass, and a bleeding colonic diverticulum. The missed findings at triphasic CT enterography were attributed to being CT occult (n = 9), perception errors (n = 4), and technical errors (n = 1). If perception errors are excluded, the sensitivity of triphasic CT enterography increases to 52% (11/21).

CONCLUSION

Triphasic CT enterography can be a useful and complementary test in the evaluation of clinically stable patients with suspected gastrointestinal bleeding by identifying the bleeding source in one third to one half of patients. Because of the potential for perception errors, radiologists should familiarize themselves with the appearance of bleeding sources at CT enterography.

Occult and obscure gastrointestinal bleeding: Causes and diagnostic approach in 2009

Gastrointestinal bleeding can be obscure or occult (OGIB), the causes and diagnostic approach will be discussed in this editorial. The evaluation of OGIB consists on a judicious search of the cause of bleeding, which should be guided by the clinical history and physical findings. The standard approach to patients with OGIB is to directly evaluate the gastrointestinal tract by endoscopy, abdominal computed tomography, angiography, radionuclide scanning, capsule endoscopy. The source of OGIB can be identified in 85%-90%, no bleeding sites will be found in about 5%-10% of cases. Even if the bleedings originating from the small bowel are not frequent in clinical practice (7.6% of all digestive haemorrhages, in our casuistry), they are notoriously difficult to diagnose. In spite of progress, however, a number of OGIB still remain problematic to deal with at present in the clinical context due to both the difficulty in exactly identifying the site and nature of the underlying source and the difficulty in applying affective and durable diagnostic approaches so no single technique has emerged as the most efficient way to evaluate OGIB.

The evaluation and management of obscure and occult gastrointestinal bleeding

Gastrointestinal (GI) bleeding is a common clinical presentation increasing in an aging population, frequently requiring hospitalization and emergent intervention, with significant morbidity, mortality, and costs. It may manifest overtly as hematemesis, melena, or hematochezia, or as an asymptomatic occult bleed. Management typically involves an esophagogastroduodenoscopy or a colonoscopy; these in combination sometimes do not identify a source of bleeding, with the source remaining obscure. Further work up to identify an obscure source frequently requires radiologically detecting the leakage of an intravascular tracer (using tagged red blood cells or angiography) with brisk bleeding or in other cases CT enterography (CTE) to detect bowel wall changes consistent with a bleeding source. Recent advances including capsule endoscopy, CTE, and double-balloon endoscopy have helped to identify bleeding sources beyond the reach of conventional endoscopy. Clinical decision-making about their use is complex and evolving. Knowing their relative merits and weaknesses including yield, contraindications, complications, and cost is essential in coming up with an appropriate management plan. This review covers the rationale for clinical management of obscure sources of GI bleeding, mentioning the approach to and the yield of conventional methods, with an emphasis on the recent advances mentioned above.

CT enterography: concept, technique, and interpretation

CT enterography is a new imaging modality that has distinct advantages over conventional CT, wireless capsule endoscopy, and barium examination. CT enterography is noninvasive and allows rapid mapping of disease activity before endoscopy and in cases where the endoscope cannot reach the diseased segment. CT enterography is readily available, is operator independent, and allows evaluation of extraenteric complications of small bowel disease. This article describes the latest techniques and applications of CT enterography.

Clinical features predicting the detection of abnormalities by double balloon endoscopy in patients with suspected small bowel bleeding

BACKGROUND AND AIM

Although double balloon endoscopy (DBE) has demonstrated a high diagnostic yield in suspected small bowel bleeding, it is not known whether DBE is of equal value to all patients with suspected small bowel bleeding or of greater benefit in selected subgroups. We aimed to determine whether any clinical features predict an increased likelihood of finding a lesion in patients with suspected small bowel bleeding.

METHODS

We retrospectively analyzed clinical features of 43 consecutive patients (M : F = 26:17, age 13-82 years) who underwent DBE because of suspected small bowel bleeding. Data associated with DBE procedure were collected prospectively. Predictive factors for the detection of a lesion were determined by comparison of clinical features between patients with positive DBE findings and those with negative findings.

RESULTS

Potential bleeding sources were discovered in 30 patients (69.8%) out of 43. Duration of bleeding was longer in patients with positive DBE findings than in those with negative findings (195 +/- 311 vs 18 +/- 17 days, P = 0.015). Number of bleeding episodes was higher in patients with positive DBE findings (2.2 +/- 1.2 vs 1.3 +/- 0.5, P = 0.011). The odds ratio for the detection of bleeding focus on DBE for patients with two or more bleeding episodes, relative to those with only one current bleeding episode was 5.67 (95% CI: 1.12-28.81, P = 0.036) in multivariate analysis.

CONCLUSION

DBE may be the most useful in patients with suspected small bowel bleeding if they have a history of frequent bleeding episodes over a long period.

Wireless capsule endoscopy indication as a predictor of study quality

PURPOSE

The aim of the study was to assess whether specific indications are associated with poor visualization during wireless capsule endoscopy (WCE) studies . Four hundred consecutive WCE studies performed at our institute were analyzed retrospectively.

RESULTS

Data was available on cases involving 176 males and 224 females. About 23 capsules failed to exit the stomach (excluded from the study). Poor visualization was reported in 66 (17%) WCE studies. The most common indications were gastrointestinal (GI) blood loss (271 cases; 72%), abdominal pain and/or diarrhea (73 cases; 19%), and suspected inflammatory bowel disease (46 cases; 12%). Of the 271 patients suffering GI bleeding, visualization was reported to be poor in 53 (19%) patients; among those showing other indications, visualization was poor in 13 (11%) patients (P = 0.02). After controlling for secondary indications and age, GI bleeding was associated with a higher rate of poor visualization compared to all other indications (odds ratio 2.6; 95% confidence interval 1.4-6.8).

CONCLUSIONS

Gastrointestinal bleeding as study indication for WCE is associated with a higher rate of poor visualization.

Management of obscure occult gastrointestinal bleeding: a cost-minimization analysis

BACKGROUND & AIMS

Capsule endoscopy (CE) and double-balloon enteroscopy (DBE) allow complete small-bowel examination but consume additional health care resources. A cost-minimization analysis determined the optimal initial management strategy for obscure occult gastrointestinal bleeding (OGIB).

METHODS

We compared 5 strategies: initial small-bowel follow-through, enteroclysis, push enteroscopy (PE), CE, or DBE. Incorporation of multiple tests was allowed with costs taken from a third-party payer perspective. We modeled medically refractory disease with 2 separate model end points in which treatment or definitive diagnosis was necessary and in which visual diagnosis was sufficient to suspend testing. Sensitivity analyses included variations in parameter estimates, Monte Carlo simulation, and structural variations in the model in which DBE was not available as an initial strategy.

RESULTS

When treatment or definitive diagnosis was necessary, the optimal strategy was initial DBE at a cost of $3824. An initial CE strategy costs an incremental $440. CE was preferred when DBE exceeded $1849 or when the sensitivity of DBE decreased to less than 68%. If DBE was unavailable as an initial test then CE was preferred to PE unless CE exceeded $1190, capsule retention was greater than 3%, or 64% of lesions were within reach of PE. When visual diagnosis was sufficient, initial CE was preferred.

CONCLUSIONS

For OGIB, initial DBE may be the least expensive strategy when treatment or definitive diagnosis is necessary and initial CE may be preferred when visual identification is sufficient. In settings where DBE is not available as an initial test, initial CE may be the preferred strategy.

Possible Role of Meckel's Scan Fused with SPECT CT Imaging: Unraveling the Cause of Abdominal Pain and Obscure-Overt Gastrointestinal Bleeding

A 27-year-old male presented with recurrent abdominal pain and high volume hematochezia despite undergoing extensive testing and a right hemicolectomy 3 years prior for a linear bleeding ulceration in the ascending colon. Studies at the University of Michigan included esophagogastroduodenoscopy (EGD), colonoscopy and video capsule endoscopy (VCE), revealing an arteriovenous malformation (AVM) in the terminal ileum. He was hospitalized for recurrent symptoms. His presentation suggested a small bowel source of obscure-overt GI bleeding based on prior non-diagnostic colonoscopy and EGD and a bilious nasogastric lavage. Tagged red blood cell scan localized bleeding to the right lower quadrant. Colonoscopy showed fresh blood in the terminal ileum without a clear source. Angiography showed no evidence of bleeding or terminal ileal AVM. A novel Meckel's scan fused with SPECT imaging showed focal uptake in the terminal ileum. The patient underwent Meckel's diverticulectomy with sparing of adjacent bowel and has remained asymptomatic for 19 months. This case illustrates that patients with obscure-overt GI bleeding require a step-wise multi-modality diagnostic work-up. Because Meckel's scans are false-positive in 28% of adults, Meckel's scan fused with SPECT imaging may offer an approach to refine diagnostic accuracy of either scan alone, but requires further investigation. Exploratory laparotomy should be reserved as a last option and is best performed with intraoperative endoscopy.

Obscure gastrointestinal bleeding: evaluation with 64-section multiphase CT enterography--initial experience

This retrospective HIPAA-compliant study was approved by the institutional review board and institutional conflict of interest committee. Patients gave informed consent for use of medical records. The purpose of the study was to retrospectively evaluate the findings depicted at computed tomographic (CT) enterography performed with a 64-section CT system and by using neutral enteric contrast material and a three-phase acquisition in patients with obscure gastrointestinal bleeding (OGIB). Twenty-two outpatients (11 men, 11 women; age range, 37-83 years) with OGIB underwent CT enterography. Findings were compared with capsule and traditional endoscopic, surgical, and angiographic findings. CT enterographic findings were positive for a bleeding source in 10 (45%) of 22 patients. Eight of 10 positive findings at CT enterography were also positive at capsule endoscopy or subsequent clinical diagnosis. CT enterography helped correctly identify three lesions undetected at capsule endoscopy. Study results suggest that multiphase, multiplanar CT enterography may have a role in the evaluation of OGIB.

Minimally Invasive Treatment of Obscure Gastrointestinal Bleeding Using Laparoscopic Ultrasonography

The management of patients with small bowel bleeding remains a diagnostic and therapeutic challenge because sensitive methods are lack and identifying the etiology and site of hemorrhage is essential in determining appropriate therapies. Accurate localization of small bowel lesions causing obscure bleeding is essential for the successful surgical treatment. However, if the lesions are small and intraluminal nature, it is impossible to identify the lesions by laparoscopy alone. We report a novel approach using the combination of laparoscopic surgery with laparoscopic ultrasonography, which enables successful minimally invasive treatment of obscure gastrointestinal bleeding caused by a submucosal tumor in proximal ileum.