Optimized multidetector computed tomographic protocol for the diagnosis of active obscure gastrointestinal bleeding: a feasibility study. J Comput Assist Tomogr. 2009;33:698-704. [PMID: 19820495 DOI: 10.1097/rct.0b013e3181937f1b]

The Role of Transcatheter Arterial Embolization in the Management of Nonvariceal Upper Gastrointestinal Bleeding

Nearly 50 years ago, catheter angiography was introduced as a means of both diagnosing and treating nonvariceal upper gastrointestinal bleeding. Technological advances and innovations have resulted in the introduction of microcatheters that, using a coaxial technique, are capable of selecting third-order arterial branches and of delivering a wide array of embolic agents. This article reviews the imaging diagnosis of nonvariceal upper gastrointestinal bleeding, the techniques of diagnostic and therapeutic angiography, the angiographic appearance of the various etiologies of nonvariceal upper gastrointestinal bleeding, the rationale behind case-specific selection of embolic agents as well as the anticipated outcome of transcatheter arterial embolization.

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.

Computed tomography angiography in patients with active gastrointestinal bleeding

Gastrointestinal bleeding represents a common medical emergency, with considerable morbidity and mortality rates, and a prompt diagnosis is essential for a better prognosis. In such a context, endoscopy is the main diagnostic tool; however, in cases where the gastrointestinal hemorrhage is massive, the exact bleeding site might go undetected. In addition, a trained professional is not always present to perform the procedure. In an emergency setting, optical colonoscopy presents limitations connected with the absence of bowel preparation, so most of the small bowel cannot be assessed. Scintigraphy cannot accurately demonstrate the anatomic location of the bleeding and is not available at emergency settings. The use of capsule endoscopy is inappropriate in the acute setting, particularly in the emergency department at night, and is a highly expensive method. Digital angiography, despite its high sensitivity, is invasive, presents catheterization-related risks, in addition to its low availability at emergency settings. On the other hand, computed tomography angiography is fast, widely available and minimally invasive, emerging as a promising method in the diagnostic algorithm of these patients, being capable of determining the location and cause of bleeding with high accuracy. Based on a critical literature review and on their own experience, the authors propose a computed tomography angiography protocol to assess the patient with gastrointestinal bleeding.

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.

Accuracy of CT angiography in the diagnosis of acute gastrointestinal bleeding: systematic review and meta-analysis

OBJECTIVE

To assess the diagnostic accuracy of computed tomography (CT) angiography in the evaluation of patients with an episode of acute gastrointestinal haemorrhage.

METHODS

Systematic review and meta-analysis to estimate pooled accuracy indices. A bivariate random effects model was adjusted to obtain a summary receiver-operating characteristic (sROC) curve and the corresponding area under the curve (AUC).

RESULTS

Twenty-two studies were included and provided data on 672 patients (range of age 5-74) with a mean age of 65 years. The overall sensitivity of CT angiography for detecting active acute GI haemorrhage was 85.2 % (95 % CI 75.5 % to 91.5 %). The overall specificity of CT angiography was 92.1 % (95 % CI 76.7 % to 97.7 %). The likelihood ratios for positive and negative test results were 10.8 (95 % CI 3.4 to 34.4) and 0.16 (95 % CI 0.1 to 0.27) respectively, with an AUC of 0.935 (95 % CI 0.693 to 0.989). The sources of heterogeneity explored had no significant impact on diagnostic performance.

CONCLUSIONS

CT shows high diagnostic accuracy and is an excellent diagnostic tool for detection and localising of intestinal bleeding sites. It is highly available, provides fast detection and localisation of the bleeding site, and is minimally invasive.

KEY POINTS

• CT angiography is increasingly used for investigating severe gastrointestinal bleeding. • This systematic review and meta-analysis updates previous ones. • In patients with massive gastrointestinal bleeding, CT angiography/MDCT detects bleeding accurately. • CT angiography is useful in locating the bleeding site and determining appropriate treatment.

[Biliodigestive anastomosis: indications, complications and interdisciplinary management]

Techniques for biliodigestive anastomoses are a frequent indication in primary surgical interventions. Moreover, they are required to manage secondary complications of hepatobiliary surgery. Evidence for the management of complications following biliodigestive anastomoses is low. Biliodigestive anastomoses can be performed as hepaticojejunostomy, hepatojejunostomy/portoenterostomy and hepaticoduodenostomy using running or single stitch suture techniques. Complication management in the hands of experienced hepatopancreatobiliary surgeons should consider a time delay to the primary operation and an interdisciplinary surgical and/or endoscopic or radiologic interventional approach. The therapy may be protracted and requires repeated critical reflection of the particular complication.

Clinical impact of multidetector computed tomography before double-balloon enteroscopy for obscure gastrointestinal bleeding

AIM: To evaluate the clinical impact of multidetector computed tomography (MDCT) before double-balloon endoscopy (DBE) for patients with obscure gastrointestinal bleeding (OGIB).

METHODS: A retrospective analysis of prospectively collected cases with DBE and MDCT for overt OGIB was conducted from April 2004 to April 2010 at Changhua Christian Hospital. We evaluated the clinical impact of MDCT on the subsequent DBE examinations and the diagnostic yields of both MDCT and DBE respectively.

RESULTS: From April 2004 to April 2010, a total of 75 patients underwent DBE for overt OGIB. Thirty one cases received MDCT followed by DBE for OGIB. The overall diagnostic yields of DBE and MDCT was 93.5% and 45.2%. The MDCT had a high diagnostic yield of tumor vs non-tumor etiology of OGIB (85.7% vs 33.3%, P = 0.014). Additionally, the choice of initial route of DBE was correct in those with a positive MDCT vs negative MDCT (100% vs 52.9%, P = 0.003).

CONCLUSION: This study suggests MDCT as a triage tool may identify patients who will benefit from DBE and aid the endoscopist in choosing the most efficient route.

3D relations between right colon arteries and the superior mesenteric vein: a preliminary study with multidetector computed tomography

BACKGROUND

3-D relations between the ileocolic (ICA), right colic artery (RCA) with the superior mesenteric vein (SMV) have been described in cadavers. However, no data exists on preoperative evaluation of these relations.

AIM

To define the length of crossing and 3-D position of the ICA and RCA to the SMV in patients undergoing multidetector computerized tomography (MDCT) angiography.

METHODS

MDCT angiographies were analyzed with the aid of Osirix v.3.0.2. image processing application. All the datasets included arterial and venous phase, undergoing multimodal visualization: 2D multiplanar reconstruction with maximum intensity projection and 3D Volume rendering. The anatomical relations were analyzed in various planes (orthogonal and oblique), depending upon their particular course. When a clear spatial reference was achieved, the distance of the colic artery from their origin on the aorta to the right border of the SMV was measured, and its position noted.

RESULTS

50 MDCT were analyzed (29 male). RCA occurred in 27 patients (54.0%), 25 (92.6%) passed anterior to the SMV. Length of crossing was 22.7±8.1 (8.3-41.3) mm. The ICA occurred in 48 (96%) passing under the SMV in 38 (79.2%). Length of crossing 15.4±5.8 (14.0-26.6) mm.

CONCLUSIONS

RCA occurs in 54% patients, passes over the SMV in 92.6% specimens and leaves a 22.7 mm stump. ICA passes under the SMV in most cases, leaving a 15.4 mm stump. These data could be of crucial importance to the surgeon facing laparoscopic right colectomy for cancer.