Obscure gastrointestinal bleeding: preliminary comparison of 64-section CT enteroclysis with video capsule endoscopy. Eur Radiol. 2011;21:79-86. [PMID: 20652705 DOI: 10.1007/s00330-010-1896-2]

Video capsule endoscopy versus computed tomography enterography in assessing suspected small bowel bleeding: a systematic review and diagnostic test accuracy meta-analysis

Both computed tomography enterography (CTE) and video capsule endoscopy (VCE) are used in identifying small intestinal pathology in patients with suspected small bowel bleeding (SSBB) following normal upper gastrointestinal endoscopy and colonoscopy. Evidence of the comparative accuracy of these two modalities is crucial for clinical and healthcare decision-making. Comprehensive electronic searches were performed for studies on CTE and/or VCE with reference standard(s). Study selection, data extraction and quality assessment were completed by two authors independently. The QUADAS-2 and QUADAS-C tools were used to assess risk of bias, and applicability. Meta-analysis was performed using a bivariate model to obtain summary estimates of sensitivity, specificity, positive and negative likelihood ratios. Twenty-five studies involving 1986 patients with SSBB were included. Four of these were head-to-head comparison of CTE and VCE. Overall, VCE provided significantly higher sensitivity of 0.74 (95% CI: 0.61-0.83) versus 0.47 (95% CI: 0.32-0.62) for CTE, while CTE showed significantly higher specificity of 0.94 (95% CI: 0.64-0.99) versus 0.53 (95% CI: .36-0.69) for VCE. The positive likelihood ratio of CTE was 7.36 (95% CI: 0.97-56.01) versus 1.58 (95% CI: 1.15-2.15) for VCE and the negative likelihood ratio was 0.49 (95% CI: 0.33-0.72) for VCE versus 0.56 (0.40-0.79) for CTE. A secondary analysis of only head-to-head comparative studies gave results that were similar to the main analysis. Certainty of evidence was moderate. Neither VCE nor CTE is a perfect test for identifying etiology of SSBB in small intestine. VCE was more sensitive while CTE was more specific. Clinicians should choose the appropriate modality depending on whether better sensitivity or specificity is required in each clinical scenario.

"MURAL" model to predict bleeding from mural-based lesions in potential small bowel bleeding may improve diagnostic capability and decrease cost

In potential small bowel bleeding, video capsule endoscopy (VCE) is excellent to detect mucosal lesions, while mural-based lesions are better detected by computed tomography enterography (CTE). A predictive tool to identify mural-based lesions should guide selecting investigations. In this retrospective study, we developed and validated the "MURAL" model based on logistic regression to predicts bleeding from mural-based lesions. Cost-effectiveness analysis comparing diagnostic strategy among VCE, CTE, and MURAL model was performed. Of 296 patients, 196 and 100 patients were randomly included in the derivative and validation cohorts, respectively. The MURAL model comprises 5 parameters: age, presence of atherosclerosis, chronic kidney disease, antiplatelet use, and serum albumin level. The area under the receiver operating characteristic curve was 0.778 and 0.821 for the derivative and validation cohorts, respectively. At a cutoff value of 24.2%, the model identified mural-based lesions with 70% sensitivity and 83% specificity in the validation cohort. Cost-effectiveness analysis revealed that application of the MURAL model demonstrated a comparable missed lesion rate but had a lower missed tumor rate, and lower cost compared to VCE strategy. The model for predicting mural-based lesions provide some guidance in investigative decision-making, which may improve diagnostic efficiency and reduce costs.

Clinical impact of wireless capsule endoscopy for small bowel investigation (Review)

Wireless capsule endoscopy is currently considered the gold standard in the investigation of the small bowel. It is both practical for physicians and easily accepted by patients. Prior to its development, two types of imaging investigations of the small bowel were available: radiologic and endoscopic. The first category is less invasive and comfortable for patients; it presents the ensemble of the small bowel, but it may imply radiation exposure. Images are constructed based on signals emitted by various equipment and require special interpretation. Endoscopic techniques provide real-time colored images acquired by miniature cameras from inside the small bowel, require interpretation only from a medical point of view, may allow the possibility to perform biopsies, but the investigation only covers a part of the small bowel and are more difficult to accept by patients. Wireless capsule endoscopy is the current solution that overcomes a part of the previous drawbacks: it covers the entire small bowel, it provides real-time images acquired by cameras, it is painless for patients, and it represents an abundant source of information for physicians. Yet, it lacks motion control and the possibility to perform biopsies or administer drugs. However, significant effort has been oriented in these directions by technical and medical teams, and more advanced capsules will surely be available in the following years.

Contrast extravasation on computed tomography angiography in patients with hematochezia or melena: Predictive factors and associated outcomes

PURPOSE

The purpose of this study was to identify variables associated with extravasation on computed tomography angiography (CTA) in patients with hematochezia/melena and compare the outcome of patients with extravasation on CTA to those without extravasation.

MATERIAL AND METHODS

Ninety-four patients (51 men, 38 women; mean age, 69 ± 16 [SD] years) who underwent CTA within 30 days of hematochezia/melena were included. Variables associated with extravasation on CTA were searched using univariable and multivariable analyses. Outcomes of patients with visible extravasation on CTA were compared with those without visible extravasation.

RESULTS

One hundred and one CTA examinations were included. Extravasation was observed on 26/101 CTA examinations (26%). At multivariable analysis the need for vasopressor drugs (odds ratio [OR], 7.6; P = 0.040), high transfusion requirements (> 2 blood units) (OR, 7.1; P = 0.014), CTA performed on the day of a hemorrhagic event (OR, 46.2; P = 0.005) and repeat CTA (OR, 27.8; P = 0.011) were independently associated with extravasation on CTA. Extravasation on CTA was followed by a therapeutic procedure in 25/26 CTAs (96%; 26 patients) compared to 13/75 CTAs (17%; 68 patients) on which no extravasation was present (P < 0.001). No patients (0/26; 0%) with contrast extravasation on CTA died while 8 patients (8/61; 13%) without contrast extravasation died, although the difference was not significant (P = 0.099).

CONCLUSION

Extravasation on CTA in the setting of hematochezia or melena is especially seen in clinically unstable patients who receive more than two blood units. Presence of active extravasation on CTA leads to more frequent application of a therapeutic procedure; however, this does not significantly affect patient outcome.

Negative Video Capsule Endoscopy Had a High Negative Predictive Value for Small Bowel Lesions, but Diagnostic Capability May Be Lower in Young Patients with Overt Bleeding

BACKGROUND

Patients with potential small bowel bleeding (PSBB) who have negative results of video capsule endoscopy (VCE), clinical course, rate of rebleeding, and missed lesions with their predictors are essential for further management decision.

METHODS

This retrospective study included patients presenting with PSBB who had negative VCE findings between January 2008 and December 2016. All patients had to have at least two years of follow-up data to be included. Patients with <2 years of follow-up in their medical record were interviewed by telephone to determine if any unrecorded rebleeding episodes occurred.

RESULTS

One hundred forty-two patients were included. The mean age was 60.9 years, and 52.8% were male. Eighty-one patients presented with overt bleeding. The median duration of follow-up was 5.08 years. During the follow-up period, 30 patients experienced rebleeding. The cumulative rate of rebleeding at 1, 2, and 5 years was 10.0%, 14.3%, and 22.4%, respectively. Multivariate analysis showed nonsteroidal anti-inflammatory drugs (NSAIDs) and presentation of overt bleeding to be independent predictors of rebleeding. There were only nine small bowel lesions (6.3%) missed by VCE. These nine patients, compared with others, were significantly younger and tended to present with overt bleeding.

CONCLUSION

Rebleeding was not uncommon in PSBB after negative VCE; however, the rate of missing small bowel lesions was low. Nonetheless, further investigations may be considered in young patients who present with overt bleeding.

CT, MRI and PET/CT features of abdominal manifestations of cutaneous melanoma: a review of current concepts in the era of tumor-specific therapies

Abdominal manifestations in patients with cutaneous melanoma include involvement due to metastatic spread and immune checkpoint inhibitor induced adverse events. The purpose of this review is to provide a critical overview of abdominal manifestations in patients with cutaneous melanoma and highlight the current imaging challenges in the era of tumor-specific therapies. Immune checkpoint inhibitors represent a treatment with demonstrated efficacy in the treatment of advanced cutaneous melanoma but are associated with several abdominal adverse events that must be recognized. CT has a role in the identification of colitis, enteritis and pancreatitis, whereas MRI has an important role in the diagnosis of autoimmune pancreatitis. Current evidence demonstrates that MRI should be the preferred imaging technique for the detection and characterization of hepatic and splenic metastases from cutaneous melanoma. The role of ¹⁸F-FDG-PET/CT should be further evaluated but current literature suggests an efficacy in the detection of pancreatic metastases not seen on CT and MRI.

Combined Use of Computed Tomography Enterography/Enteroclysis and Capsule Endoscopy Improves the Accuracy of Diagnosis of Small Bowel Bleeding

Objective CT enterography/enteroclysis (CTE) is listed in the clinical practice guidelines as a method for diagnosing small bowel bleeding, as is capsule endoscopy (CE), but there are no real-world data yet available on CTE in Japan. This study aimed to investigate the diagnostic ability of CTE and long-term prognosis after CTE in Japan. Patients We conducted a retrospective cohort study of patients suspected of having small bowel bleeding who underwent both CTE and CE within 30 days between April 2008 and March 2019. The number of patients free from rebleeding for up to 24 months was thus determined. Results Seventy-one patients were extracted from the database. The 43 patients (60.6%) with a definite and suspicious source of bleeding in the small bowel were detected by CTE. When the 31 patients with a definite source of bleeding in the small bowel were analyzed, the sensitivity of CTE was 19/31 (61.3%) and that of CE was 24/31 (77.4%), thus indicating no significant difference (p=0.332). However, the sensitivity when CTE and CE were used in combination was 30/31 (96.8%), which was significantly higher than that of CE alone (p=0.0412). No rebleeding was observed in the CTE and CE negative group (p=0.0965). Conclusion The combined use of CTE and CE increased the detection rate of small bowel bleeding. Therefore, in patients with suspected tumor/polyp lesions, not only CE, but also CTE should be performed. This study provides the first real-world data on the diagnostic accuracy of CTE for small bowel bleeding in Japan.

Management of obscure gastrointestinal bleeding: Comparison of guidelines between Japan and other countries

Small-bowel bleeding accounts for the majority of obscure gastrointestinal bleeding, but it is caused by various types of small bowel disease, upper gastrointestinal disease, and colorectal disease. For the diagnosis, history taking and physical examination are required, leading to a determination of what diseases are involved. Next, cross-sectional imaging, such as computed tomography, should be carried out, followed by the latest enteroscopy such as small bowel capsule endoscopy and deep enteroscopy according to the severity of hemorrhage and patient condition. After a comprehensive diagnosis, medical, enteroscopic, or surgical treatment should be selected. This article reviews recent advances in the endoscopic diagnosis of obscure gastrointestinal bleeding and compares perspectives of the management of obscure gastrointestinal bleeding in Japan with that in other countries.

Diagnosis of chronic anaemia in gastrointestinal disorders: A guideline by the Italian Association of Hospital Gastroenterologists and Endoscopists (AIGO) and the Italian Society of Paediatric Gastroenterology Hepatology and Nutrition (SIGENP)

Anaemia is a common pathologic condition, present in almost 5% of the adult population. Iron deficiency is the most common cause; other mechanisms can be involved, making anaemia a multi-factorial disorder in most cases. Anaemia being a frequent manifestation in the diseases of the gastrointestinal tract, patients are often referred to gastroenterologists. Furthermore, upper and lower endoscopy and enteroscopy are pivotal to the diagnostic roadmap of anaemia. In spite of its relevance in the daily clinical practice, there is a limited number of gastroenterological guidelines dedicated to the diagnosis of anaemia. For this reason, the Italian Association of Hospital Gastroenterologists and Endoscopists and the Italian Society of Paediatric Gastroenterology, Hepatology and Nutrition commissioned a panel of experts to prepare a specific guideline on anaemia and its diagnostic roadmap in the gastroenterological scenario. The panel also discussed about the potential involvement of gastroenterologists and endoscopists in the management of patients with anaemia, with particular attention to the correct use of investigations. The panel paid particular attention to practical issues with the aim to support gastroenterologists in their clinical practice when dealing with patients with anaemia.

Diagnostic and therapeutic considerations for obscure gastrointestinal bleeding in patients with chronic kidney disease

Recurrent obscure gastrointestinal bleeding amongst patients with chronic kidney disease is a challenging problem gastroenterologists are facing and is associated with an extensive diagnostic workup, limited therapeutic options, and high healthcare costs. Small-bowel angiodysplasia is the most common etiology of obscure and recurrent gastrointestinal bleeding in the general population. Chronic kidney disease is associated with a higher risk of gastrointestinal bleeding and of developing angiodysplasia compared with the general population. As a result, recurrent bleeding in this subgroup of patients is more prevalent and is associated with an increased number of endoscopic and radiographic procedures with uncertain benefit. Alternative medical therapies can reduce re-bleeding; however, more studies are needed to confirm their efficacy in this subgroup of patients.

The diagnostic ability of SPECT/CT fusion imaging for gastrointestinal bleeding: a retrospective study

Background

Blood loss from the gastrointestinal tract can be an acute and life-threatening event. For the treatment of gastrointestinal bleeding, it is important to accurately detect gastrointestinal bleeding and to localize the sites of bleeding. The purpose of this study was to retrospectively assess the capabilities of SPECT/CT in the diagnosis of gastrointestinal bleeding by a comparison with planar imaging alone as well as planar and SPECT.

Methods

We conducted a retrospective analysis of 20 patients (21 examinations) who underwent gastrointestinal bleeding scintigraphy in the past 7 years and in whom the bleeding site was identified by endoscopy or capsule endoscopy, or in whom no evidence of gastrointestinal bleeding was identified during the clinical course. Five patients (5 examinations) were diagnosed by planar imaging (planar group). Eight patients (9 examinations) were diagnosed by planar imaging and SPECT (planar + SPECT group). Seven patients (7 examinations) were diagnosed by planar imaging and SPECT/CT (planar + SPECT/CT group). We calculated the diagnostic ability of each method in detecting the presence of bleeding, as well as the ability of each method to identify the sites of bleeding. The sensitivity, specificity, and accuracy of the methods were compared.

Results

The diagnostic ability of the three imaging methods in detecting the presence of gastrointestinal bleeding was as follows. Planar imaging showed 100% sensitivity (3/3), 100% specificity (2/2), and 100% accuracy (5/5). Planar + SPECT imaging showed 85.7% sensitivity (6/7), 100% specificity (2/2), and 88.9% accuracy (8/9). Planar + SPECT/CT imaging showed 100% sensitivity (6/6), 100% specificity (1/1), and 100% accuracy (7/7). The diagnostic ability of the three modalities in detecting the site of bleeding was as follows: planar, 33.3% (1/3); planar + SPECT, 71.4% (5/7); and planar + SPECT/CT, 100% (6/6).

Conclusions

All 3 imaging methods showed good accuracy in detecting the presence of gastrointestinal bleeding. The addition of SPECT or SPECT/CT made the anatomical position of the uptake clear and contributed to the localization of the site of gastrointestinal bleeding. Planar + SPECT/CT imaging therefore showed the highest diagnostic ability for detecting the site of gastrointestinal bleeding.

Accuracy of Computed Tomographic Enterography for Obscure Gastrointestinal Bleeding: A Diagnostic Meta-analysis

RATIONALE AND OBJECTIVES

Obscure gastrointestinal bleeding (OGIB) is the bleeding from the gastrointestinal tract without definite source that persists and recurs after a negative endoscopic evaluation. The study aimed to systematically evaluate the diagnostic accuracy of computed tomography enterography on OGIB detection by meta-analysis.

MATERIALS AND METHODS

Studies were searched in relevant databases. With predefined inclusion criteria, eligible studies were included, followed by quality assessment using the Quality Assessment of Diagnostic Accuracy Studies scoring system. The Meta-DiSc software was used to implement the meta-analysis, and sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio with their 95% confidence intervals (CIs) were used as the effect size. Publication bias was determined by Egger test.

RESULTS

A set of nine studies was included in this meta-analysis, having a relatively high quality. Under the random effects model, the pooled sensitivity and specificity were 0.724 (95% CI: 0.651-0.789) and 0.752 (95% CI: 0.691-0.807), respectively. Under the fixed effects model, the pooled positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were 2.949 (95% CI: 2.259-3.850), 0.393 (95% CI: 0.310-0.497), and 9.452 (95% CI: 5.693-15.692), respectively. The area under curve of the summary receiver operating characteristic curve was 0.7916 (95% CI: 0.723-0.860). No obvious publication bias was detected (t = 1.62, P = .181).

CONCLUSIONS

Computed tomography enterography might be used as a complementary to video capsule endoscopy instead of an alternative for the detection of OGIB.

Primary small bowel adenocarcinoma: current view on clinical features, risk and prognostic factors, treatment and outcome

Small bowel adenocarcinoma (SBA) is a rare but increasing cause of gastrointestinal malignancy, being both a diagnostic and therapeutic challenge. The goal of treatment is margin negative resection of a lesion and local lymphadenectomy, followed by modern adjuvant chemotherapy combinations in selected cases. Improved outcomes in patients with SBA are encouraging, but elucidation of mechanisms of carcinogenesis and risk factors as well as improved treatment for this malignancy is very needed.

Mass-forming lesions of the duodenum: A pictorial review

Recent advances in imaging have resulted in marked changes in the investigation of the duodenum, which still remains primarily evaluated with videoendoscopy. However, improvements in computed tomography (CT) and magnetic resonance (MR) imaging have made detection and characterization of duodenal mass-forming abnormalities easier. The goal of this pictorial review was to illustrate the most common conditions of the duodenum that present as mass-forming lesions with a specific emphasis on CT and MR imaging. MR imaging used in conjunction with duodenal distension appears as a second line imaging modality for the characterization of duodenal mass-forming lesions. CT remains the first line imaging modality for the detection and characterization of a wide range of duodenal mass-forming lesions.

A Prospective Blinded Comparison of Video Capsule Endoscopy Versus Computed Tomography Enterography in Potential Small Bowel Bleeding: Clinical Utility of Computed Tomography Enterography

GOALS

To compare the efficacy of video capsule endoscopy (VCE) with computed tomography enterography (CTE) in potential small bowel (SB) bleeding, and to identify factors predictive of a high diagnostic yield for CTE.

BACKGROUND

In potential SB bleeding, CTE potentially detects some lesions missed by VCE, but few data have determined its clinical utility.

STUDY

Consecutive patients with potential SB bleeding were prospectively enrolled. All underwent VCE and CTE within a 1-week interval. Definitive diagnoses were made by surgery or enteroscopy, except when a strategy of VCE and conservative management was suitable. The diagnostic yields and sensitivities of each investigation were measured.

RESULTS

Fifty-two patients were recruited (41 with overt and 11 with occult bleeding); 36 received a definitive diagnosis. The diagnostic yields and sensitivities of VCE and CTE were 59.6% and 30.8% (P=0.004), and 72.2% and 44.4% (P=0.052), respectively. The combined sensitivity of VCE and CTE (88.9%) was significantly greater than VCE (P=0.03) or CTE (P<0.01) alone. VCE was better for ulcers, enteritis, and angiodysplasia, whereas CTE was better for tumors and Meckel diverticula. Age below 40 years and severe bleeding were associated with a higher diagnostic yield for CTE [odds ratios (95% confidence interval)=7.3 (1.04-51.4), P=0.046 and 6.1 (1.4-25.5), P=0.014, respectively].

CONCLUSIONS

Both investigations complement each other in the diagnosis of potential SB bleeding. CTE should be considered when VCE is negative. Age below 40 years and severe bleeding were independent predictors of a higher diagnostic yield for CTE.

Detection of small-bowel tumours with CT enteroclysis using carbon dioxide and virtual enteroscopy: A preliminary study

PURPOSE

The aim of this prospective study was to evaluate the feasibility, tolerance and performance of virtual enteroscopy (VE) using carbon dioxide for small-bowel distension in patients with suspected small-bowel tumours (SBTs).

PATIENTS AND METHODS

After IRB approval, 17 patients with suspected SBTs were prospectively included. Radiation dose was compared to 34 matched patients (2 for 1) for age, gender and body weight, who had undergone CT-enteroclysis with neutral contrast (CTE). Performance of VE was evaluated through comparison with the current standard of reference, including surgery and/or enteroscopy and/or follow-up.

RESULTS

Tolerance was excellent in 16/17 patients (94%). The radiation dose was lower for VE than for CTE (533 ± 282 vs. 974 ± 505 mGy.cm; p = 0.002). With VE, a total of 25 polyps >5 mm in size were depicted in 12/17 patients. On a per-lesion analysis, sensitivity and positive predictive value of VE were 92.0% and 92.0%, respectively. On a per-segment analysis VE had a sensitivity and specificity of 95.0% and 87.0%, respectively.

CONCLUSION

Our preliminary study suggests that VE is a feasible and well-tolerated technique with high sensitivity and specificity for the diagnosis of SBT.

KEY POINTS

• Virtual enteroscopy is feasible and well tolerated. • Virtual enteroscopy appears to be accurate for detection of small-bowel tumours. • Sensitivity and PPV of virtual enteroscopy is 92.0% and 92.0%. • Radiation dose is lower with virtual enteroscopy compared to MDCT-enteroclysis.

Neoplastic Diseases of the Small Bowel

The incidence of small bowel tumors is increasing over time. Until recently, their diagnosis was delayed and it was often reached only at the time of surgery. New diagnostic tools, such as capsule endoscopy, device-assisted enteroscopy, and dedicated small bowel cross-sectional imaging techniques, have been introduced recently in clinical practice. The combination of these tools allows medical practitioners to detect small bowel tumors at an early stage and to reach a definite diagnosis before surgery, thus enabling minimally invasive treatments.

Diagnostic value of capsule endoscopy and CT enteroclysis in obscure gastrointestinal bleeding

AIM

To assess the diagnostic value of capsule endoscopy (CE) and computed tomography (CT) enteroclysis in obscure gastrointestinal bleeding (OGIB).

METHODS

We retrospectively analyzed the clinical data for 70 patients with OGIB who underwent capsule endoscopy and CT enteroclysis between January 2011 and June 2016 at Jiangsu People's Hospital. The detection rates, disease diagnosis rates and diagnostic coincidence between the two modalities were analyzed.

RESULTS

The overall detection rate of OGIB by capsule endoscopy was much higher than that by CT enteroclysis [90.00% (63/70) vs 22.86% (16/70), P = 0.000]. Further study showed that the etiological diagnosis rate of OGIB by capsule endoscopy was higher than that by CT enteroclysis (61.43% vs 10.00%, P = 0.000). The diagnosis coincidence between these two was only 27.14%. The overall detection rate and etiological diagnosis rate of OGIB by combination capsule endoscopy with CT enteroclysis were slightly superior to capsule endoscopy, but there was no significance (P > 0.05). The overall detection rate by capsule endoscopy in patients with overt bleeding was higher than that in patients with occult bleeding (94.83% vs 66.67%, P = 0.015). The diagnosis of vascular lesions, erosion/ulcer and diverticulum by capsule endoscopy was superior to that of CT enteroclysis. It was worth mentioning that the diagnosis of intestinal tumor by CT enteroclysis was higher than that by capsule endoscopy (4 cases found by CT enteroclysis were confirmed by surgery. Only 2 of them were also found by capsule endoscopy).

CONCLUSION

Both capsule endoscopy and CT enteroclysis are safe and effective in diagnosing OGIB. The diagnostic rate of OGIB by capsule endoscopy is significantly higher than that by CT enteroclysis. Although the value of capsule endoscopy combined with CT enteroclysis is not superior to capsule endoscopy alone, it may be complimentary in some cases when there is no finding checked by capsule endoscopy in OGIB patients, especially in the diagnosis of small intestinal tumors.

[Clinical Efficacy of Dynamic Contrast-enhanced Multidetector-row Computed Tomography in Patients with Obscure Gastrointestinal Bleeding]

BACKGROUND/AIMS

Obscure gastrointestinal bleeding (OGIB) accounts for 5% of all gastrointestinal (GI) bleeding cases. Dynamic contrast-enhanced multidetector-row CT (DCE-MDCT) is not generally recommended in OGIB patients due to its low sensitivity. However, it can be used to quickly and simply diagnose OGIB according to some guidelines. The aim of this study was to evaluate the clinical efficacy of DCE-MDCT in OGIB patients.

METHODS

We retrospectively analyzed the medical records of 362 patients who underwent DCE-MDCT between March 2009 and January 2014. A total of 45 patients diagnosed with OGIB were included in this study. Their baseline characteristics and treatment procedure were analyzed retrospectively. The positive rates of DCE-MDCT for the detection of bleeding and associated factors were assessed.

RESULTS

The mean age of the patients was 59 years, and males represented 51.1%. Melena was the most common symptom (44.4%). Positive rate of DCE-MDCT findings was 20.0% (9/45). Among these patients, intraluminal contrast extravasation was found in 5 patients (55.6%) and intraluminal hematoma or mass lesions were found in 2 patients each (22.2%). Thirty nine patients (86.7%) underwent conservative management, and 6 patients (13.3%) underwent specific treatment, such as endoscopic treatment, embolization, or surgery. Patients who showed positivity in DCE-MDCT more frequently received specific treatment compared with those who were negative (44.4% vs. 5.6%, p=0.010).

CONCLUSIONS

Although DCE-MDCT showed a low positive rate (20.0%), positive findings of DCE-MDCT could lead to specific treatment. Positive DCE-MDCT findings play a useful role in the management of patients with OGIB.

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.

ACG Clinical Guideline: Diagnosis and Management of Small Bowel Bleeding

Bleeding from the small intestine remains a relatively uncommon event, accounting for ~5-10% of all patients presenting with gastrointestinal (GI) bleeding. Given advances in small bowel imaging with video capsule endoscopy (VCE), deep enteroscopy, and radiographic imaging, the cause of bleeding in the small bowel can now be identified in most patients. The term small bowel bleeding is therefore proposed as a replacement for the previous classification of obscure GI bleeding (OGIB). We recommend that the term OGIB should be reserved for patients in whom a source of bleeding cannot be identified anywhere in the GI tract. A source of small bowel bleeding should be considered in patients with GI bleeding after performance of a normal upper and lower endoscopic examination. Second-look examinations using upper endoscopy, push enteroscopy, and/or colonoscopy can be performed if indicated before small bowel evaluation. VCE should be considered a first-line procedure for small bowel investigation. Any method of deep enteroscopy can be used when endoscopic evaluation and therapy are required. VCE should be performed before deep enteroscopy if there is no contraindication. Computed tomographic enterography should be performed in patients with suspected obstruction before VCE or after negative VCE examinations. When there is acute overt hemorrhage in the unstable patient, angiography should be performed emergently. In patients with occult hemorrhage or stable patients with active overt bleeding, multiphasic computed tomography should be performed after VCE or CTE to identify the source of bleeding and to guide further management. If a source of bleeding is identified in the small bowel that is associated with significant ongoing anemia and/or active bleeding, the patient should be managed with endoscopic therapy. Conservative management is recommended for patients without a source found after small bowel investigation, whereas repeat diagnostic investigations are recommended for patients with initial negative small bowel evaluations and ongoing overt or occult bleeding.

Multidisciplinary management of gastrointestinal fibrotic stenosis in Crohn's disease

Crohn's disease (CD) is a chronic inflammatory bowel disease that can involve virtually any part of the gastrointestinal tract. CD complications are the main indications for surgery. A large proportion of these interventions are due to stricturing disease. Although immunosuppressive treatments have been used more frequently during the last 25 years, there is no significant decrease in the need for surgery in patients with CD. Unfortunately, surgery is not curative, as the disease ultimately reoccurs in a substantial subset of patients. To best identify the patients who will require a specific treatment and to plane the most appropriate therapeutic approach, it is important to precisely define the type, the size, and the location of CD stenosis. Diagnostic approaches aim to distinguish fibrotic from inflammatory strictures. Medical therapy is required for inflammatory stenosis. Mechanical treatments are required when fibrotic CD strictures are symptomatic. The choice between endoscopic balloon dilation, stricturoplasty, and laparoscopic or open surgery is based on the presence of perforating complications, the remaining length of small bowel, and the number and length of strictures. The non-hierarchical decision-making process for the treatment of fibrotic CD therefore requires multidisciplinary clinical rounds with radiologists, gastroenterologists, interventional endoscopists, and surgeons.

Beneficial effects of combining computed tomography enteroclysis/enterography with capsule endoscopy for screening tumor lesions in the small intestine

Aim. To compare the efficacy of using computed tomography enteroclysis/enterography (CTE), capsule endoscopy (CE), and CTE with CE for diagnosing tumor lesions in the small intestine. Materials and Methods. We included 98 patients who underwent CE during the observation period and were subjected to CTE at our hospital from April 2008 to May 2014. Results. CTE had a significantly higher sensitivity than CE (84.6% versus 46.2%, P = 0.039), but there were no significant differences in specificity, positive or negative predictive values, or diagnostic accuracy rates. The sensitivity of CTE/CE was 100%, again significantly higher than that of CE (P = 0.002). The difference in specificity between CTE/CE and CE was not significant, but there were significant differences in positive predictive values (100% for CTE/CE versus 66.7% for CE, P = 0.012), negative predictive values (100% versus 92.1%, P = 0.008), and diagnostic accuracy rate (100% versus 89.8%, P = 0.001). The diagnostic accuracy rate was also significantly higher in CTE/CE versus CTE (100% versus 95.9%, P = 0.043). Conclusion. Our findings suggested that a combination of CTE and CE was useful for screening tumor lesions in the small intestine. This trial is registered with number UMIN000016154.

Obscure gastrointestinal bleeding: diagnosis and treatment

Small-bowel bleeding comprises a majority of obscure gastrointestinal bleeding, but is caused by various kinds of diseases. For its diagnosis, history-taking and physical examination is requisite, leading to a suspicion of what diseases are involved. Next, cross-sectional imaging such as computed tomography should be done, followed by the latest enteroscopy, videocapsule endoscopy and deep enteroscopy according to the severity of hemorrhage and patient conditions. After comprehensive diagnosis, medical, enteroscopic, or surgical treatment should be selected.

CT enteroclysis/enterography findings in drug-induced small-bowel damage

OBJECTIVE

To evaluate the CT enteroclysis (CTE)/enterography findings of patients with small-bowel mucosal damage induced by aspirin or non-steroidal anti-inflammatory drugs (NSAIDs) and to compare these findings with the duration of drug use and endoscopic findings.

METHODS

CTE findings of 11 patients (22 lesions) with drug-induced small-bowel damage were reviewed, including 8 NSAID users and 3 aspirin users. Three patients were short-term users (6 months or shorter) and eight were long-term users (3 years or longer). Nine patients also underwent videocapsule endoscopy (VCE) or double-balloon enteroscopy (DBE).

RESULTS

Small-bowel abnormalities were visible in 8 of 11 patients (73%) on CTE. Multiple lesions were seen in five patients, including all short-term users. Lesions were classified into three types. Type 1 (mucosal patchy enhancement) was found in four of eight patients (50%, 12 lesions) all were short-term users. Small erosions with mild oedema/redness were shown by DBE. Type 2 (homogeneous hyperenhancement) was found in two of eight patients (25%, four lesions) who were long-term users. Large ulcers with marked oedema/redness were shown by DBE. Type 3 (stratification enhancement) was found in four of eight patients (50%, six lesions), both short-term and long-term users. Annular or large ulcers with strictures were shown by VCE or DBE.

CONCLUSION

On CTE, Type 1 lesions in patients with mostly short-term aspirin or NSAID use, Type 2 lesions in patients with long-term use and Type 3 lesions in both types of patients were detected. CTE may have usefulness for the detection of mild damage.

ADVANCES IN KNOWLEDGE

Small-bowel abnormalities owing to aspirin or NSAID present with three different patterns on CTE.

Obscure gastrointestinal bleeding: diagnostic performance of 64-section multiphase CT enterography and CT angiography compared with capsule endoscopy

OBJECTIVE

To compare the diagnostic capabilities between capsule endoscopy (CE) and multislice CT (MSCT) enterography in combination with MSCT angiography for assessment of obscure gastrointestinal bleeding (OGIB).

METHODS

A total of 127 patients with OGIB were looked at in this study. 82 patients (aged 42.7 ± 19.1 years; 34 males) were assigned to receive MSCT diagnosis and 67 patients to (aged 53.9 ± 16.2 years; 28 males) receive CE diagnosis. Among them, 22 patients (aged 54.1 ± 19.1 years; 12 males) received both examinations. Oral isotonic mannitol and intramuscular injection of anisodamine were performed; non-ionic contrast (iopromide, 370 mg I ml(-1)) was intravenously administered; and then multiphase scanning was conducted at arterial, small intestinal and portal venous phases in MSCT. The results were compared with findings of reference standards including double balloon enteroscopy, digital subtraction angiography, intraoperative pathological examination and/or clinical diagnosis.

RESULTS

Administration of anisodamine markedly increased the satisfaction rate of bowel filling (94.67% vs 28.57%; p < 0.001) but not the diagnostic yield (p = 0.293) of MSCT. Compared with MSCT, CE showed an improved overall diagnostic yield (68.66% vs 47.56%; p = 0.010), which was also observed in overt bleeding patients (i.e. patients with continued passage of visible blood) (76.19% vs 51.02%; p = 0.013) and in patients aged younger than 40 years of age (85% vs 51.28%; p = 0.024). However, CE had similar positive rates to MSCT (p > 0.05). Among the 22 cases in whom both examinations were conducted, CE showed no significantly different diagnostic capability compared with MSCT (p = 0.4597).

CONCLUSION

Both CE and MSCT are safe and effective diagnostic methods for OGIB.

ADVANCES IN KNOWLEDGE

CE is preferred for overt bleeding or patients aged younger than 40 years. The combined use of CE and MSCT is recommended in OGIB diagnosis.

Update on imaging of Peutz-Jeghers syndrome

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

Enteroscopy for the early detection of small bowel tumours in at-risk celiac patients

BACKGROUND

A subset of celiac patients shows a high risk for small bowel malignancies.

AIMS

To select celiac patients considered at risk and evaluate the diagnostic yield of enteroscopy in this context.

METHODS

Celiac patients were enrolled from a tertiary referral centre during the period June 2011-June 2013, based on the following criteria: (i) patients diagnosed when aged 50+ and with poor response to gluten-free dieting; (ii) low dietary compliance; (iii) alarm symptoms. The patients underwent small bowel capsule endoscopy and/or double-balloon enteroscopy. Control populations were represented by the 165 non-celiac patients undergoing capsule endoscopy for obscure gastrointestinal bleeding, and the 815,362-strong population of the Italian province of Varese as a registered cohort.

RESULTS

Fifty-three patients (19% males, mean age 43.6±17.4 years) were evaluated. Two jejunal adenocarcinomas and one ileal neuro-endocrine tumour were diagnosed by enteroscopy (the diagnostic yield for malignancies in the selected population being 5.7%). In the non-celiac controls the detection rate of small bowel tumours by capsule endoscopy was 0.6% (P=0.04). When compared to the registered population, the relative risk for intestinal malignancy was 1282 (95% CI, 407-4033; P<0.0001).

CONCLUSIONS

Capsule endoscopy and double-balloon enteroscopy can be considered for early disease management of a subset of celiac patients.

Small bowel tumors detected and missed during capsule endoscopy: Single center experience

AIM: To characterize small bowel (SB) tumors detected by capsule endoscopy (CE), and identify missed tumors.

METHODS: The study included 145 consecutive patients in whom 150 CEs were performed. Following CE, the medical records of the study population were reviewed. Results of double- or single-balloon enteroscopy performed after CE and the results of surgery in all patients operated on were retrieved. The patients were contacted through telephone interviews or postal mail. In addition, the national cancer registry and the polish clinical gastrointestinal stromal tumor (GIST) Registry were searched to identify missed neoplasms.

RESULTS: Indications for CE included overt and occult obscure gastrointestinal bleeding (n = 81, 53.7%), anemia (n = 19, 12.7%), malabsorption (n = 18, 12%), abnormal CB follow through (n = 9, 6%), abdominal pain (n = 7, 5%), celiac disease (n = 5, 3%), neuroendocrine tumor (n = 3, 2%), Crohn’s disease (n = 2, < 2%), Peutz-Jeghers syndrome (n = 2, < 2%), other polyposes (n = 2, < 2%), and diarrhea (n = 2, < 2%). The capsule reached the colon in 115 (76.6%) examinations. In 150 investigations, CE identified 15 SB tumors (10%), 14 of which were operated on or treated endoscopically. Malignancies included metastatic melanoma (n = 1), adenocarcinoma (n = 2), and GIST (n = 3). Benign neoplasms included dysplastic Peutz-Jeghers polyps (n = 4). Non-neoplastic masses included venous malformation (n = 1), inflammatory tumors (n = 2), and a mass of unknown histology (n = 1). During the follow-up period, three additional SB tumors were found (2 GISTs and one mesenteric tumor of undefined nature). The National Cancer Registry and Polish Clinical GIST Registry revealed no additional SB neoplasms in the post-examination period (follow-up: range 4.2-102.5 mo, median 39 mo). The sensitivity of CE for tumor detection was 83.3%, and the negative predictive value was 97.6%. The specificity and positive predictive value were both 100%.

CONCLUSION: Neoplasms may be missed by CE, especially in the proximal SB. In overt obscure gastrointestinal bleeding, complementary endoscopic and/or radiologic diagnostic tests are indicated.

Comparison of MR enteroclysis with video capsule endoscopy in the investigation of small-intestinal disease

Purpose

To evaluate the diagnostic accuracy of MR enteroclysis and to compare it to video capsule endoscopy (VCE) in the analysis of suspected small-bowel disease.

Methods

We performed a retrospective analysis of 77 patients who underwent both MR enteroclysis and VCE and compared the findings of these studies with the findings of enteroscopy, surgery, or with the results of clinical follow-up lasting ≥2 years.

Results

Findings included malignant neoplasms (n = 13), benign neoplasms (n = 10), refractory celiac disease (n = 4), Crohn’s disease (n = 2) and miscellaneous conditions (n = 10). Specificity of MR enteroclysis was higher than that of VCE (0.97 vs. 0.84, P = 0.047), whereas sensitivity was similar (0.79 vs. 0.74, P = 0.591). In 2/32 (6.3%) patients with both negative VCE and negative MR enteroclysis a positive diagnosis was established, compared to 5/11 (45.5%) patients in whom VCE was positive and MR enteroclysis was negative (likelihood ratio 8.1; P = 0.004), 9/11 (81.8%) patients in whom MR enteroclysis was positive and VCE was negative (likelihood ratio 23.5; P < 0.0001), and all 23 patients in whom both VCE and MR enteroclysis showed abnormalities (likelihood ratio 60.8; P < 0.0001).

Conclusions

VCE and MR enteroclysis are complementary modalities. In our study-population, MR enteroclysis was more specific than VCE, while both produced the same sensitivity.

Small-bowel capsule endoscopy: a ten-point contemporary review

The introduction of capsule endoscopy (CE) in clinical practice increased the interest for the study of the small-bowel. Consequently, in about 10 years, an impressive quantity of literature on indications, diagnostic yield (DY), safety profile and technical evolution of CE has been published as well as several reviews. At present time, there are 5 small-bowel capsule enteroscopy (SBCE) models in the worldwide market. Head-to-head trials have showed in the great majority of studies comparable results in terms of DY, image quality and completion rate. CE meta-analyses formed the basis of national/international guidelines; these guidelines place CE in a prime position for the diagnostic work-up of patients with obscure gastrointestinal bleeding, known and/or suspected Crohn's disease and possible small-bowel neoplasia. A 2-L polyethylene glycol-based purge, administered the day before the procedure, is the most widely practiced preparation regimen. Whether this regimen can be further improved (i.e., by further decreasing its volume, changing the timing of administration, coupling it with prokinetics and/or other factors) or if it can really affect the DY, is still under discussion. Faecal calprotectin has been used in SBCE studies in two settings: in patients taking non-steroidal anti-inflammatory drugs, to evaluate the type and extent of mucosal damage and, more importantly from a clinical point of view, in patients with known or suspected Crohn's disease for assessment of inflammation activity. Although there is still a lot of debate around the exact reasons of SBCE poor performance in various small-bowel segments, it is worth to remember that the capsule progress is non-steerable, hence more rapid in the proximal than in lower segments of the small-bowel. Capsule aspiration, a relatively unexpected complication, has been reported with increasing frequency. This is probably related with the increase in the mean age of patients undergoing CE. CE video review is a time-consuming procedure. Therefore, several attempts have been made to develop technical software features, in order to make CE video analysis easier and shorter (without jeopardizing its accuracy). Suspected Blood Indicator, QuickView and Fujinon Intelligent Chromo Endoscopy are some of the software tools that have been checked in various clinical studies to date.

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.

Prospective evaluation of magnetic resonance enterography for the detection of mesenteric small bowel tumours

PURPOSE

To prospectively evaluate magnetic resonance (MR) enterography for detecting mesenteric small-bowel tumours (MSBTs) and assess the added value of gadolinium-chelate injection.

MATERIAL AND METHODS

Over a 2-year period MR enterography examinations of 75 patients (33 men, 42 women; mean age, 53.8 years; range, 19-85) with suspected MSBT were blindly analysed by two readers for the presence of MSBT. Sensitivities, specificities, predictive positive values (PPVs), negative predictive values (NPVs) and accuracies of MR enterography for the detection of MSBT were calculated on per-patient and per-lesion bases. The McNemar test was used to compare sensitivities and specificities of the unenhanced and gadolinium-enhanced sets of MR enterographies.

RESULTS

Thirty-seven MSBTs were pathologically confirmed in 26 patients. The mean tolerance score of the examinations was 0.7. On a per-patient basis, sensitivity, specificity, PPV, NPV and accuracy for detection of MSBT were 96 % [95 % CI, 89-100 %], 96 % [90-100 %], 93 % [83-100 %], 98 % [94-100 %] and 96 % [92-100 %], respectively. On a per-lesion basis, sensitivity and PPV were 70 % [56-85 %] and 93 % [83-100 %], respectively. Gadolinium injection yielded higher sensitivities on both bases (P = 0.008).

CONCLUSION

MR enterography is an accurate and well-tolerated imaging modality for detecting MSBT. Intravenous administration of gadolinium-chelate improves sensitivity for MSBT detection.

KEY POINTS

• MR enterography accurately detects mesenteric small bowel tumours. • MR enterography is a well-tolerated imaging technique. • Intravenous administration of gadolinium chelate improves sensitivity for detecting small-bowel tumours.

Carcinoid tumors of the small-bowel: evaluation with 64-section CT-enteroclysis

PURPOSE

To describe the imaging presentation of carcinoid tumors of the small-bowel at 64-section CT-enteroclysis and determine the sensitivity of this technique for tumor detection.

PATIENTS AND METHODS

The 64-section CT-enteroclysis examinations of 22 patients with histopathologically proven small-bowel carcinoid tumors and those of 6 patients with suspected recurrence after small-bowel resection for carcinoid tumor were reviewed. Images were analyzed with respect to imaging presentation. Sensitivity, specificity, and accuracy, of 64-section CT-enteroclysis for the diagnosis of carcinoid tumor of the small-bowel were estimated with 95% confidence intervals (CIs).

RESULTS

Twenty-five carcinoid tumors were confirmed in 22 patients (prevalence, 22/28; 79%). Overall sensitivity for carcinoid tumor detection was 76% (19/25; 95%CI: 55-91%) on a per-lesion basis. On a per-patient basis, 64-section CT-enteroclysis had a sensitivity of 86% (19/22; 95%CI: 65-97%), a specificity of 100% (6/6; 95%CI: 54-100%) and an accuracy of 89% (25/28; 95%CI: 72-98%) for the diagnosis of carcinoid tumor. Focal small-bowel wall thickening, mesenteric stranding, and mesenteric mass were found in 20/22 (91%), 18/22 (82%) and 15/22 (68%) patients with pathologically confirmed tumors.

CONCLUSION

64-Section CT-enteroclysis shows highly suggestive features for the diagnosis of carcinoid tumor of the small-bowel and achieves high degrees of sensitivity for tumor detection.

Guideline for capsule endoscopy: obscure gastrointestinal bleeding

Capsule endoscopy (CE) is considered as a noninvasive and reliable diagnostic tool of examining the entire small bowel. CE has been performed frequently at many medical centers in South Korea; however, there is no evidence-based CE guideline for adequate diagnostic approaches. To provide accurate information and suggest correct testing approaches for small bowel disease, the guideline on CE was developed by the Korean Gut Image Study Group, a part of the Korean Society of Gastrointestinal Endoscopy. Operation teams for developing the guideline were organized into four areas: obscure gastrointestinal bleeding, small bowel preparation, Crohn's disease, and small bowel tumor. A total of 20 key questions were selected. In preparing this guideline, MEDLINE, Cochrane library, KMbase, KISS, and KoreaMed literature searches were performed. After writing a draft of the guideline, opinions from various experts were reflected before approving the final document. The guideline should be regarded as recommendations only to gastroenterologists in providing care to their patients. These are not absolute rules and should not be construed as establishing a legal standard of care. Although further revision may be necessary as new data appear, this guideline is expected to play a role for adequate diagnostic approaches of various small bowel diseases.

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.

Helical CT-enteroclysis in the detection of small-bowel tumours: a meta-analysis

OBJECTIVE

To perform a meta-analysis to determine sensitivity and specificity estimates of helical CT-enteroclysis in the detection of small-bowel tumours.

METHODS

A search for relevant articles published from January 1992 to November 2010 was performed. Study design, patient characteristics and 2 × 2 contingency tables were recorded for eligible studies. Heterogeneity was assessed with the I (2) statistic. A bivariate generalised linear random-effects model was used to summarise sensitivity and specificity estimates for small-bowel tumour detection on a per-patient basis. Sensitivity and specificity estimates were compared in different subgroups.

RESULTS

Twelve studies (696 patients) were eligible. The mean small-bowel tumour prevalence was 22.6 % (range 7.7-45.8 %). Inter-study heterogeneity was substantial for sensitivity (I (2) = 66.9 %; 95 % CI 28.7-88.5 %) and low for specificity (I (2) = 10.6 %; 95 % CI 0.0-55.0 %). On a per-patient basis, pooled sensitivity was 92.8 % (95 % CI 71.3-98.5 %) and pooled specificity 99.2 % (95 % CI 94.2-99.9 %) for the diagnosis of small-bowel tumour. Subgroup analysis revealed that small-bowel preparation, more than one imaging pass and large volumes (≥2 L) of enteral contrast agent did not improve tumour detection.

CONCLUSION

Our meta-analysis confirms that helical CT-enteroclysis has high degrees of sensitivity and specificity for small-bowel tumour detection. However, our findings reinforce the need for more standardised individual studies.

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.

Obscure gastrointestinal bleeding: difficulties in comparing CT enterography and video capsule endoscopy

A paper reports the results of a retrospective study that was designed to evaluate the potential role of video capsule endoscopy (VCE) in elucidating the cause of bleeding in patients with obscure gastrointestinal bleeding (OGIB) for whom CT enterography was negative. The authors highlight the limitations of dual-phase CT enterography for the detection of flat lesions of the small bowel such as ulcers, angiodysplasias or arteriovenous malformations, and confirm the superiority of VCE for the detection of this category of lesions. This commentary discusses some of the issues raised.

KEY POINTS

• Video capsule endoscopy surpasses CT enterography in detecting flat small bowel lesions. • Retrospective VCE and CT enterography findings in obscure bleeding need further evaluation. • A fair and unbiased comparison of the two investigations is still needed.

The role of capsule endoscopy after negative CT enterography in patients with obscure gastrointestinal bleeding

OBJECTIVES

The aim of the present study was to evaluate the role of capsule endoscopy in patients with obscure gastrointestinal bleeding (OGIB) after negative computed tomographic (CT) enterography.

METHODS

We retrospectively included 30 patients with OGIB who received capsule endoscopy after negative CT enterography. The median age of the patients was 60 years, and 60% of patients were male. The median follow-up duration was 8 months. Overt bleeding was 60%, and occult bleeding was 40%.

RESULTS

Based on capsule endoscopy results, a definitive diagnosis was made for 17 patients (57%): ulcer in nine patients (30%), active bleeding with no identifiable cause in five (17%), angiodysplasia in two (7%) and Dieulafoy's lesion in one (3%). Two patients with jejunal ulcers were diagnosed with Crohn's disease. Seven patients (41%) with positive capsule endoscopy received double balloon enteroscopy and two patients (12%) received steroid treatment for Crohn's disease. Patients with overt bleeding, a previous history of bleeding, or who received large amounts of blood transfusions were more likely to show positive capsule endoscopy.

CONCLUSIONS

Capsule endoscopy showed high diagnostic yields in patients with OGIB after negative CT enterography and may help to provide further therapeutic plans for patients with OGIB and negative CT enterography.

KEY POINTS

• CT enterography has been widely used in evaluating obscure gastrointestinal bleeding (OGIB). • Capsule endoscopy showed high diagnostic yield for OGIB after negative CT enterography. • Negative CT enterography does not exclude important causes of small bowel bleeding. • Most lesions missed at CT-enterography are flat and can be detected by capsule endoscopy.

Detection and localization of active gastrointestinal bleeding with multidetector row computed tomography angiography: a 5-year prospective study in one medical center

GOAL

To prospectively assess the utility of multidetector row computed tomography angiography (MDCTA) in the diagnosis of active gastrointestinal bleeding (GIB).

BACKGROUND

MDCTA is a relatively recent advance in CT scanning technology enabling excellent vascular visualization and detection of various vascular abnormalities. However, there is no prospective study with a large population evaluating the role of MDCTA in the diagnosis of active GIB.

STUDY

From January 2006 to January 2011, 113 consecutive patients with clinical signs of active GIB underwent MDCTA (16-slice, 64-slice, or dual-source). The criteria for positive CT findings included active extravasation of contrast material within bowel lumen, abnormal bowel mucosal enhancement, vascular malformation, abnormally enhancing polyp or diverticulum, or tumor. Two radiologists reviewed the images and assessed CT findings in consensus. The standards of reference included digital subtraction angiography, endoscopy, surgery, or final pathology reports. Sensitivity, specificity, positive and negative predictive values, and accuracy of MDCTA for detection of active GIB were evaluated.

RESULTS

Positive CT findings for active GIB were identified in 80 of 113 patients (70.8%), all of which were confirmed by 1 or more reference standard. Negative MDCTA results were obtained in 33 patients (29.2%). Of these, 27 patients did not require any further intervention and were discharged without incident. The overall sensitivity, specificity, positive and negative predictive values, and accuracy of MDCTA was 86.0%, 100%, 100%, 60.6%, and 88.5%, respectively.

CONCLUSIONS

MDCTA is an accurate first-line screening method for detection and localization of GIB and can guide triage in patients with active GIB.

Computed tomography enteroclysis: a review

Computed tomography (CT) enteroclysis is being performed routinely for evaluation of suspected small bowel diseases. The availability of multidetector CT scanners has further increased the diagnostic yield of enteroclysis. There is excellent depiction of small bowel wall pathology on CT enteroclysis especially with use of negative enteric contrast. We discuss the CT enteroclysis technique and procedure along with the imaging spectrum of some common small bowel pathologies.

CT-enterography may identify small bowel tumors not detected by capsule endoscopy: eight years experience at Mayo Clinic Rochester

BACKGROUND

Capsule endoscopy (CE) is widely accepted as the preferred diagnostic test in the evaluation of small bowel diseases. However, small bowel tumors (SBT) are sometimes missed by CE. Preliminary studies suggest that CT-enterography (CTE) may play a role in detecting SBT.

AIMS

The purpose of this study was to compare the performance of CE and CTE in detecting SBT METHODS: This was a single center, retrospective study. Patients treated at the Mayo Clinic Rochester between January 2000 and December 2008 with a discharge diagnosis of SBT and negative initial esophagogastroduodenoscopy (EGD) and colonoscopy were identified through a search of the electronic medical records. Among 103 identified patients, 41 had undergone CE, CTE or both, and comprised our study group. The exact binomial sensitivity of CE and CTE in detecting SBT was calculated. Demographic characteristics, clinical presentation, results of diagnostic tests, and tumor characteristics were recorded for each patient.

RESULTS

CTE and CE detected 38/41 (sensitivity 92.7%; 95% CI 80.1-98.5) and 8/27 (sensitivity 29.6%; 95% CI 13.8-50.2) of the SBT identified at Mayo Clinic Rochester, respectively. Seventeen patients had both CTE and CE. In this subgroup of patients, CTE detected SBT in 16/17 (sensitivity 94.1; 95% CI 72.7-99.9) and CE in 6/17 (sensitivity 35.3%; 95% CI 13.3-59). The matched paired difference in the sensitivity of two techniques in detecting SBT was statistically significant (P = 0.004).

CONCLUSION

CTE may identify SBT not diagnosed by CE.

[Gastrointestinal bleeding: the role of radiology]

Gastrointestinal bleeding represents a diagnostic challenge both in its acute presentation, which requires the point of bleeding to be located quickly, and in its chronic presentation, which requires repeated examinations to determine its etiology. Although the diagnosis and treatment of gastrointestinal bleeding is based on endoscopic examinations, radiological studies like computed tomography (CT) angiography for acute bleeding or CT enterography for chronic bleeding are becoming more and more common in clinical practice, even though they have not yet been included in the clinical guidelines for gastrointestinal bleeding. CT can replace angiography as the diagnostic test of choice in acute massive gastrointestinal bleeding, and CT can complement the endoscopic capsule and scintigraphy in chronic or recurrent bleeding suspected to originate in the small bowel. Angiography is currently used to complement endoscopy for the treatment of gastrointestinal bleeding.

A prospective evaluation of iron deficiency anemia in the GI endoscopy setting: role of standard endoscopy, videocapsule endoscopy, and CT-enteroclysis

BACKGROUND

Iron deficiency anemia (IDA) is a frequently encountered condition in clinical practice. After conventional endoscopy, the cause of anemia remains unknown in up to 40% of patients.

OBJECTIVE

To evaluate prospectively the diagnostic efficacy of a systematic endoscopic approach to IDA and to compare the diagnostic yield of videocapsule endoscopy (VCE) and CT-enteroclysis in endoscopy-negative patients.

DESIGN

Consecutive patients with IDA were enrolled prospectively.

SETTING

Open-access endoscopy within an academic hospital.

PATIENTS

This study involved 189 patients with IDA, including 98 women and 91 men; mean (±standard deviation) age 68 years±16.6 years.

INTERVENTION

Patients with IDA underwent gastroscopy and colonoscopy plus ileoscopy. Endoscopy-negative patients were further blindly evaluated by both CT-enteroclysis and VCE.

MAIN OUTCOME MEASUREMENTS

Diagnostic yield of conventional endoscopy; diagnostic yield of VCE versus CT-enteroclysis.

RESULTS

Endoscopy results were positive in 144 of 189 patients (76.2%). CT-enteroclysis and VCE allowed a diagnosis in 37 of 45 endoscopy-negative patients (82.2%). Overall, VCE was superior to CT-enteroclysis (77.8% vs 22.2%; P<.001), in particular when flat lesions were found.

LIMITATIONS

Single-center study.

CONCLUSION

A systematic approach to IDA, which includes standard endoscopy, VCE, and CT-enteroclysis allows an overall diagnostic rate of 95.7%; however, CT-enteroclysis should be limited to cases of nondiagnostic VCE.