Oral contrast enhanced bowel ultrasonography in the assessment of small intestine Crohn's disease. A prospective comparison with conventional ultrasound, x ray studies, and ileocolonoscopy

How to perform gastrointestinal ultrasound: Anatomy and normal findings

Gastrointestinal ultrasound is a practical, safe, cheap and reproducible diagnostic tool in inflammatory bowel disease gaining global prominence amongst clinicians. Understanding the embryological processes of the intestinal tract assists in the interpretation of abnormal sonographic findings. In general terms, the examination principally comprises interrogation of the colon, mesentery and small intestine using both low-frequency and high-frequency probes. Interpretation of findings on GIUS includes assessment of bowel wall thickness, symmetry of this thickness, evidence of transmural changes, assessment of vascularity using Doppler imaging and assessment of other specific features including lymph nodes, mesentery and luminal motility. In addition to B-mode imaging, transperineal ultrasonography, elastography and contrast-enhanced ultrasonography are useful adjuncts. This supplement expands upon these features in more depth.

A comprehensive review and update on Crohn's disease

The term inflammatory bowel disease (IBD) refers principally to two major categories of chronic relapsing inflammatory intestinal disorders: Crohn's disease (CD) and ulcerative colitis (UC). In the United States, it is currently estimated that about 1.5 million people suffer from IBD, causing considerable suffering, mortality and economic loss every year. Yet the cause of IBD is unknown, and until we understand more, prevention or cure will not be possible. There is a lot of variation in the incidence and prevalence of CD based on geographic region, environment, immigrant population, and ethnic groups. The annual incidence of CD in North America is reported to be 3.1-20.2 per 100,000 with a prevalence of 201 per 100,000 population. Based on the epidemiological, genetic and immunological data, CD is considered to be a heterogeneous disorder with multifactorial etiology in which genetics and environment interact to manifest the disease. Several genes have been studied so for with respect to CD, but thus far the strong and replicated associations have been identified with NOD2, IL23R and ATG16L1 genes. The risk factors implicated with CD include smoking, low fiber- high carbohydrate diet, altered microbiome and medications such as non-steroidal anti-inflammatory drugs. CD is typically characterized by transmural inflammation of the intestine and could affect any part of the gastrointestinal tract from mouth to perianal area. In terms of distribution of the disease 25% of the patients have colitis only, 25% is ileitis only and 50% have ileocolitis. The Montreal classification is based on the age at diagnosis (<16, 17-40, > 40), disease location (Ileal, colonic, Ileocolonic) and the disease behavior (nonstricturing/nonpenetrating, stricturing, penetrating). The key features for diagnosing CD comprises a combination of radiographic, endoscopic and pathological findings demonstrating focal, asymmetric, transmural or granulomatous features. Abdominal Computed tomography (CT) enterography is the most preferred first-line radiologic study used in the assessment of small bowel CD. The diagnostic accuracy of magnetic resonance enterography/enteroclysis is similar to that of CT scans and also prevents exposure to ionizing radiation. Endoscopic scores are considered to be the gold standard tool to measure the activity of CD and they are used more commonly in the clinical trials to measure the efficacy of various drugs on inducing and maintaining mucosal healing. The most common scoring systems used to measure clinical disease activity include Crohn's Disease Activity Index (CDAI), HBI- Harvey-Bradshaw index (HBI), short inflammatory bowel disease questionnaire (SIBDQ) and Lehmann score. Management of Crohn's disease has been seen as an evolving challenge owing to its widely heterogeneous manifestations, overlapping characteristics with other inflammatory disorders, often elusive extraintestinal manifestations and uncertain etiology. Therapeutic interventions are tailored to address symptomatic response and subsequent tolerance of the intervention. Chronology of treatment should favor treatment dose acute disease or "induction therapy", followed by maintenance of adequate response or remission, i.e. "maintenance therapy". The medications which are highly effective in inducing remission include steroids and Tumor Necrosis Factor (TNF) inhibitors. Medications used to maintain remission include 5-aminosalicyclic acid products, immunomodulators (Azathioprine, 6-mercaptopurine, methotrexate) and TNF inhibitors (infliximab, adalimumab, certolizumab and golimumab). Surgical interventions like bowel resection, stricturoplasty or drainage of abscess is required in up to two thirds of CD patients during their lifetime. The most common indications for surgical resection are medically refractory disease, perforation, persisting or recurrent obstruction, abscess not amenable to percutaneous drainage, intractable hemorrhage, dysplasia or cancer. Endoscopic recurrence in postoperative CD patients, as defined by Rutgeers score i2-i4 occur in 30-90% of the patients at the neoterminal ileum within 12 months of surgery and almost universally by 5 years. Treating CD requires a comprehensive care team including the patient, primary care provider, and gastroenterologist. In summary CD is a chronic inflammatory condition with a remitting and relapsing course primarily affecting relatively younger population with significant socioeconomic effects.

Role of Bowel Ultrasound in the Diagnosis and Follow-up of Patients with Crohn's Disease

Crohn's disease (CD) is an inflammatory chronic bowel disorder; it can involve the whole gastrointestinal tract, but its localization in the ileum or colon is most common. The reference standard for the diagnosis of CD is ileocolonoscopy with histologic assessment. The reference standard for the detection of any complications is surgery. However, imaging techniques have an important role both in the detection/localization of CD and in the follow-up of CD patients. In the last few years, the technical development of ultrasound equipment, the advent of new technologies such as elastography and mostly the increased expertise of sonographers have boosted the role of bowel ultrasound in assessment of the gastrointestinal tract. In fact, bowel ultrasound is particularly attractive thanks to its widespread availability, non-invasiveness, low cost and good reproducibility, as it can be easily repeated during follow-up. The aim of this article is to provide an extensive overview of the actual role of bowel ultrasound in the detection and follow-up of patients with CD.

Use of Intestinal Ultrasound to Monitor Crohn's Disease Activity

BACKGROUND & AIMS

We performed a multicenter study to determine whether transabdominal bowel wall ultrasonography, a noninvasive procedure that does not require radiation, can be used to monitor progression of Crohn's disease (CD).

METHODS

We performed a 12-month prospective, noninterventional study at 47 sites in Germany, from December 2010 through September 2014. Our study included 234 adult patients with CD who experienced a flare, defined as Harvey-Bradshaw index score of ≥7. All patients received treatment intensification, most with tumor necrosis factor antagonists. Ultrasound parameters and clinical data were assessed at baseline and then after 3, 6, and 12 months. The primary endpoint was the change in ultrasound parameters within 12 months of study enrollment.

RESULTS

All patients included had bowel wall alterations either within the terminal ileum and/or segments of the colon. After 3 and 12 months, ultrasonographic examination showed significant improvements of nearly all ultrasound parameters, including reductions in bowel wall thickening or stratification, decreased fibrofatty proliferation, and increased signals in color Doppler ultrasound (P < .01 for all parameters at months 3 and 12). Median Harvey-Bradshaw index scores decreased from 10 at baseline to 2 after 12 months. Improvement in bowel wall thickness correlated with reduced levels of C-reactive protein after 3 months (P ≤ .001).

CONCLUSIONS

In a multicenter prospective study, we found that ultrasonographic examination can be used to monitor disease activity in patients with active CD. Bowel ultrasonography seems to be an ideal follow-up method to evaluate early transmural changes in disease activity, in response to medical treatment. German Clinical Trials Register: drks.de/DRKS00010805.

SICUS and CEUS imaging in Crohn's disease: an update

Endoscopy remains the main technique in the diagnosis and treatment of Crohn's disease (CD); nevertheless, the recent development of innovative and non-invasive imaging techniques has led to a new tool in the exploration of small bowel in CD patients. This paper reviews the available data on ultrasound imaging used for the evaluation of CD, highlighting the role of small intestine contrast-enhanced ultrasonography with the use of oral and intravenous contrast agents.

Oral Contrast-Enhanced Gastric Ultrasonography in the Assessment of Gastric Lesions: A Large-Scale Multicenter Study

OBJECTIVE

To determine the diagnostic efficiency of oral contrast-enhanced gastric ultrasonography in the evaluation of gastric lesions, based on large-scale multicenter study.

METHODS

The study enrolled 383,945 patients with suspect gastric lesions who underwent complete oral contrast-enhanced gastric ultrasonography and endoscopic evaluation. Two operators, unaware of the results of other diagnostic procedures, performed each examination independently. The accuracies of conventional ultrasonography, oral contrast-enhanced gastric ultrasonography, and upper gastrointestinal endoscopy were determined.

RESULTS

After oral contrast, the anatomy of the stomach and morphologic features of gastric lesions were clearly visualized. The sensitivities, specificities, positive predictive values, negative predictive values and accuracies of oral contrast-enhanced ultrasonography in detecting the sites, sizes, numbers, and the extent of gastric lesions,were similar to those of upper gastrointestinal endoscopy (P > .05) and far greater than those of conventional ultrasonography (P < .01). Moreover, oral contrast-enhanced ultrasonography was far better than upper gastrointestinal endoscopy (P < .01) and was better than conventional ultrasonography (P < .05) in detecting the submucosal abnormalities (<5mm) and the adjacent structures abnormalities identified in surgical pathology. However, oral contrast-enhanced ultrasonography was a bit poorer than upper gastrointestinal endoscopy (P < .05) and far better than conventional ultrasonography (P < .01) in detecting the minor mucosal abnormalities (<5mm).

CONCLUSION

Oral contrast-enhanced gastric ultrasonography is superior to conventional gastric ultrasonography in defining the anatomic location and extension of gastric lesions. Its diagnostic performance is not worse than upper gastrointestinal endoscopy and it can be used as a useful supplement to upper gastrointestinal endoscopy.

Bowel Thickening in Crohn's Disease: Fibrosis or Inflammation? Diagnostic Ultrasound Imaging Tools

The high frequency of intestinal strictures in patients with Crohn's disease and the different treatment approaches specific for each type of stenosis make the differentiation between fibrotic and inflammatory strictures crucial in management of the disease. However, there is no standardized approach to evaluate and discriminate intestinal strictures, and until now, there was no established cross-sectional imaging modality to detect fibrosis. New techniques, such as contrast-enhanced ultrasound and sonoelastography allow the assessment of vascularization and mechanical properties of stenotic bowel tissue, respectively. These techniques have shown great potential to characterize strictures in Crohn's disease. The aim of this review is to sum up the current knowledge on bowel ultrasound tools to discriminate inflammatory from fibrotic stenosis in Crohn's disease considering the most recent published studies in the field.

Utility of MR enterography and ultrasound for the investigation of small bowel Crohn's disease

Cross sectional Imaging plays an increasingly important role the diagnosis and management of Crohn's disease. Particular emphasis is placed on MRI and Ultrasound as they do not impart ionising radiation. Both modalities have reported high sensitivity for disease detection, activity assessment and evaluation of extra-luminal complications, and have positive effects on clinical decision making. International Guidelines now recommend MRI and Ultrasound in the routine management of Crohn's disease patients. This article reviews the current evidence base supporting both modalities with an emphasis on the key clinical questions. We describe current protocols, basic imaging findings and highlight areas in need of further research.

LEVEL OF EVIDENCE

5 Technical Efficacy: Stage 4 J. MAGN. RESON. IMAGING 2017;45:1573-1588.

The use of ultrasound in inflammatory bowel disease

Imaging in inflammatory bowel disease (IBD) plays a pivotal role in the primary diagnosis, as well as during the management of patients with known IBD. The evolution of ultrasound equipment and the growing expertise of examiners have both enhanced the role of intestinal ultrasound in the assessment of the gastrointestinal tract in IBD patients. Intestinal ultrasound has been shown to have high sensitivity and specificity, as well as high positive and negative predictive value, in the detection or exclusion of intestinal inflammatory activity in IBD. The obvious advantages of intestinal ultrasound over other imaging modalities include non-invasiveness, rapid availability and low costs. This review summarizes the current developments in the use of intestinal ultrasound for the detection of IBD and its complications, and discusses its use in the management of patients with IBD. Indications for the use of intestinal ultrasound in daily practice are presented, expanded by new developments such as contrast-enhanced ultrasonography and elastography.

The first joint ESGAR/ ESPR consensus statement on the technical performance of cross-sectional small bowel and colonic imaging

Objectives

To develop guidelines describing a standardised approach to patient preparation and acquisition protocols for magnetic resonance imaging (MRI), computed tomography (CT) and ultrasound (US) of the small bowel and colon, with an emphasis on imaging inflammatory bowel disease.

Methods

An expert consensus committee of 13 members from the European Society of Gastrointestinal and Abdominal Radiology (ESGAR) and European Society of Paediatric Radiology (ESPR) undertook a six-stage modified Delphi process, including a detailed literature review, to create a series of consensus statements concerning patient preparation, imaging hardware and image acquisition protocols.

Results

One hundred and fifty-seven statements were scored for agreement by the panel of which 129 statements (82 %) achieved immediate consensus with a further 19 (12 %) achieving consensus after appropriate modification. Nine (6 %) statements were rejected as consensus could not be reached.

Conclusions

These expert consensus recommendations can be used to help guide cross-sectional radiological practice for imaging the small bowel and colon.

Key points

• Cross-sectional imaging is increasingly used to evaluate the bowel

• Image quality is paramount to achieving high diagnostic accuracy

• Guidelines concerning patient preparation and image acquisition protocols are provided

Small intestine contrast ultrasonography for the detection and assessment of Crohn disease: A meta-analysis

BACKGROUND

Crohn disease (CD) is a chronic relapsing disease. Imaging modalities are essential for the diagnosis and assessment of CD. Small intestine contrast ultrasonography (SICUS) is a well-tolerated, noninvasive and radiation-free modality and has shown potential in CD assessment. We aimed at evaluating the diagnostic accuracy of SICUS in the detection and assessment of small-bowel lesions and complications in CD.

METHODS

We searched PubMed database for relevant studies published before April 24, 2016. We integrated the true positive, false positive, false negative, and true negative into the pooled estimates of sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio. Forest plots were to represent the pooled results of all studies.

RESULTS

Thirteen articles were finally considered eligible. The pooled sensitivity and specificity of SICUS in detecting small-bowel lesions were 0.883 (95% confidence interval (CI) 0.847-0.913) and 0.861 (95% CI 0.828-0.890), respectively. The pooled diagnostic odds ratio was 39.123 (95% CI 20.014-76.476) and the area under the curve of summary receiver operating characteristic was 0.9273 (standard error: 0.0152). In subgroup analyses, SICUS represented fine sensitivity and specificity in proximal and distal small intestine lesion, as well as in CD-related complications such as stricture, dilation, abscess, and fistula.

CONCLUSION

SICUS is accurate enough to make a complete assessment about the location, extent, number, and almost all kinds of complications in CD small-bowel lesions.

European Crohn's and Colitis Organisation Topical Review on Prediction, Diagnosis and Management of Fibrostenosing Crohn's Disease

This ECCO topical review of the European Crohn's and Colitis Organisation [ECCO] focused on prediction, diagnosis, and management of fibrostenosing Crohn's disease [CD]. The objective was to achieve evidence-supported, expert consensus that provides guidance for clinical practice.

Endoscopy and cross-sectional imaging for assessing Crohn׳s disease activity

Crohn's disease (CD) is principally characterized by chronic and recurrent inflammation of the gastrointestinal tract, most commonly found in the ileo-colonic region. The chronicity and severity of intestinal inflammation together contribute to progressive, cumulative, deep, transmural intestinal damage, including stricturing, obstruction, abscesses, and fistulae. Both intestinal inflammation and its chronic complications result in a range of symptoms subsequently leading to patient presentations with diarrhea, abdominal pain, and anemia related to intestinal blood loss. Measuring disease activity and severity are essential for decision of treatment intensity early in the disease course and longitudinal monitoring of therapeutic efficacy. This review will summarize the transition from subjective symptoms driving disease activity indices, into increasingly objective and quantitative measures of intestinal injury by direct mucosal assessment (endoscopy), cross-sectional imaging, and surrogate biomarkers. Specific commentary on intestinal stricture and perianal fistula assessment and management are presented in accompanying sections of this series.

Particularities of Crohn's disease in pediatric patients: current status and perspectives regarding imaging modalities

A consensus on the best imaging modality evaluating inflammatory bowel disease in the pediatric population is lacking and it is often unclear which modality to choose in specific clinical circumstances. Children with inflammatory bowel disease are exposed to ionizing radiation from multiple imaging studies performed at initial diagnosis, throughout treatment and during the follow-up period. This paper discusses the value of different imaging techniques in pediatric patients with inflammatory bowel disease and gives a review of the literature. In addition, particular features of inflammatory bowel disease in children including the predilection of affected segments in the gastrointestinal tract are highlighted. Based on current literature knowledge, we encourage an integrative approach to the interpretation of clinical and imaging data for diagnosis and follow-up in daily clinical settings.

Medical Imaging in Small Bowel Crohn's Disease-Computer Tomography Enterography, Magnetic Resonance Enterography, and Ultrasound: "Which One Is the Best for What?"

BACKGROUND

Small bowel imaging in Crohn's disease (CD) is an important adjunct to endoscopy for the diagnosis, assessment of postoperative recurrence, and detection of complications. The best imaging modality for such indications though remains unclear. This systematic review aims to identify the imaging modality of choice considering the use of ultrasound (US), computed tomography enterography (CTE), and magnetic resonance enterography (MRE).

METHODS

Databases were systematically searched for studies pertaining to the performance of US, CTE, and MRE, as compared with a predefined reference standard in the assessment of small bowel CD.

RESULTS

Thirty-three studies, from a total of 1427 studies, were included in the final analysis. A comparable performance was demonstrated for MRE, CTE, and US for the diagnosis of small CD. Ultrasound was found to have the highest accuracy in the differentiation of inflammation and fibrosis. Postoperative recurrence detection was feasible with the use of MRE and US. All 3 modalities were shown to have a role in the detection of small bowel CD complications. The radiation exposure associated with CTE can be minimized by using lower radiation protocols.

CONCLUSIONS

Ultrasound, CTE, and MRE all play an important role in the diagnosis and management of small bowel CD, with preference for a particular modality being influenced by specific indication, institution resources, and patient preference.

Bowel Ultrasonography in the Management of Crohn's Disease. A Review with Recommendations of an International Panel of Experts

BACKGROUND

Bowel ultrasonography (US) is considered a useful technique for assessing mural inflammation and complications in Crohn's disease (CD). The aim of this review is to appraise the evidence on the accuracy of bowel US for CD. In addition, we aim to provide recommendations for its optimal use.

METHODS

Publications were identified by literature search from 1992 to 2014 and selected based on predefined criteria: 15 or more patients; bowel US for diagnosing CD, complications, postoperative recurrence, activity; adequate reference standards; prospective study design; data reported to allow calculation of sensitivity, specificity, agreement, or correlation values; articles published in English.

RESULTS

The search yielded 655 articles, of which 63 were found to be eligible and retrieved as full-text articles for analysis. Bowel US showed 79.7% sensitivity and 96.7% specificity for the diagnosis of suspected CD, and 89% sensitivity and 94.3% specificity for initial assessment in established patients with CD. Bowel US identified ileal CD with 92.7% sensitivity, 88.2% specificity, and colon CD with 81.8% sensitivity, 95.3% specificity, with lower accuracy for detecting proximal lesions. The oral contrast agent improves the sensitivity and specificity in determining CD lesions and in assessing sites and extent.

CONCLUSIONS

Bowel US is a tool for evaluation of CD lesions in terms of complications, postoperative recurrence, and monitoring response to medical therapy; it reliably detects postoperative recurrence and complications, as well as offers the possibility of monitoring disease progression.

Current Role of Ultrasound in Small Bowel Imaging

Bowel ultrasound is cheap, relatively quick, allows dynamic evaluation of the bowel, has no radiation burden, is well tolerated by patients, and allows repeat imaging. Bowel ultrasound requires a systematic assessment of the entire bowel using high-frequency probes. In addition, hydrosonography and contrast-enhanced ultrasound may be performed. We present the normal sonographic appearances of large and small bowel and the sonographic appearances of acute appendicitis, Crohn's disease, celiac disease, intussusception, infectious enteritis, intestinal tuberculosis, small bowel ileus and obstruction, small bowel ischemia, and malignant tumors.

Diagnostic imaging and radiation exposure in inflammatory bowel disease

Diagnostic imaging plays a key role in the diagnosis and management of inflammatory bowel disease (IBD). However due to the relapsing nature of IBD, there is growing concern that IBD patients may be exposed to potentially harmful cumulative levels of ionising radiation in their lifetime, increasing malignant potential in a population already at risk. In this review we explore the proportion of IBD patients exposed to high cumulative radiation doses, the risk factors associated with higher radiation exposures, and we compare conventional diagnostic imaging with newer radiation-free imaging techniques used in the evaluation of patients with IBD. While computed tomography (CT) performs well as an imaging modality for IBD, the effective radiation dose is considerably higher than other abdominal imaging modalities. It is increasingly recognised that CT imaging remains responsible for the majority of diagnostic medical radiation to which IBD patients are exposed. Magnetic resonance imaging (MRI) and small intestine contrast enhanced ultrasonography (SICUS) have now emerged as suitable radiation-free alternatives to CT imaging, with comparable diagnostic accuracy. The routine use of MRI and SICUS for the clinical evaluation of patients with known or suspected small bowel Crohn’s disease is to be encouraged wherever possible. More provision is needed for out-of-hours radiation-free imaging modalities to reduce the need for CT.

Bowel Ultrasonography in Inflammatory Bowel Disease

BACKGROUND

The diagnosis of inflammatory bowel disease (IBD) is based on a combination of endoscopic, clinical and biochemical investigations as well as cross-sectional imaging. The applications of cross-sectional imaging in IBD are manifold. Ultrasonography has emerged as an important imaging modality in the diagnosis of Crohn's disease (CD) as well as for monitoring disease progression and in the therapeutic response to CD and ulcerative colitis (UC). Key Messages: Ultrasonography is non-invasive, radiation free, cheap, easy to use and well tolerated and accepted by patients. Bowel ultrasonography can be used for the primary diagnosis of CD as it has a similar sensitivity and specificity like that of MRI and CT, particularly in the case of CD. Ultrasonography can also be used to monitor treatment response to therapy and to detect disease recurrence of CD as well as UC. In CD, ultrasonography can also be used to detect complications such as strictures as well as extramural complications, including abscesses and fistulas. Contrast-enhanced ultrasonography is a useful tool that might be helpful to detect certain indications in CD, in particular the differentiation between abscesses and inflammation.

CONCLUSION

A variety of advantages of bowel ultrasonography over other imaging modalities suggest the more frequent use of this method to manage IBD patients in daily practice. Bowel ultrasonography should be a standard tool in IBD centers.

Diagnostic accuracy of three different MRI protocols in patients with inflammatory bowel disease

BACKGROUND

Magnetic resonance imaging (MRI) is used for workup and control of inflammatory bowel disease (IBD); however, disagreement remains as to how the MRI should be performed.

PURPOSE

To compare prospectively the diagnostic accuracy of MRI with neither oral nor intravenous contrast medium (plain MRI), magnetic resonance follow-through (MRFT) and MR enteroclysis (MRE) using MRE as the reference standard in patients with inflammatory bowel disease.

MATERIAL AND METHODS

Plain MRI and MRE were carried out in addition to MRFT. All patients underwent both plain MR and MRFT on the same day and MRE within seven days. For the evaluation, the bowel was divided into nine segments. One radiologist, blinded to clinical findings, evaluated bowel wall thickness, diffusion weighted imaging (DWI), mural hyperenhancement, and other inflammatory changes in each bowel segment.

RESULTS

Twenty patients (6 men, 14 women; median age, 43.5 years; age range, 26-76 years) underwent all three examinations; 10 with Crohn's disease (CD), three with ulcerative colitis (UC), and seven with IBD unclassified (IBD-U). Sensitivity, specificity, and accuracy were in the range of 0-75%, 81-96%, and 75-95% for wall thickening, and 0-37%, 59-89%, and 50-86% for DWI in plain MRI, respectively. Sensitivity, specificity, and accuracy were in the range of 0-50%, 96-100%, and 90-100% for wall thickening, 0-50%, 84-97%, and 82-95% for DWI, and 0-71%, 94-100%, and 85-100% for mural hyperenhancement in MRFT, respectively.

CONCLUSION

The use of oral and intravenous contrast agent improves detection of bowel lesions resulting in MRFT remaining the superior choice over plain MRI for diagnostic workup in patients with IBD.

Positioning Ultrasonography Into Clinical Practice for the Management of Crohn's Disease

Over the past few years, the technical evolution of ultrasound equipment, the use of oral and intravenous contrast agents, and an increase in the expertise of operators have enhanced the role that ultrasonography plays in the assessment of the gastrointestinal tract. For patients with chronic inflammatory conditions, particularly Crohn's disease, it has been suggested that ultrasonography can be used not only for diagnostic purposes but also in disease management. These developments are reviewed in this article.

Prediction of T stage in gastric carcinoma by enhanced CT and oral contrast-enhanced ultrasonography

Background

The aim of this study is to explore the values of enhanced CT and oral contrast-enhanced ultrasonography on preoperative T stage in gastric carcinoma.

Methods

Forty patients with gastric carcinoma, including 27 males and 13 females, were confirmed by endoscopy, operation, and pathology. The median age of these patients was 49 years old (25 to 73 years). There were 19 cases of well-differentiated adenocarcinoma, 13 cases of poorly differentiated adenocarcinoma, 5 cases of signet ring cell carcinoma, and 4 cases of mucinous adenocarcinoma by pathology. All these patients were examined by both enhanced CT and ultrasound examination simultaneously 1 week before surgery. T staging in all these gastric carcinomas was carried out by enhanced CT or oral contrast-enhanced ultrasonography, respectively, or by both of them. The statistical difference between T stage by imaging and pathological T stage was analyzed.

Results

In this study, there were 5 cases with T1 stage, 9 cases with T2 stage, 20 cases with T3 stage, and 6 cases with T4 stage by pathology; 5 cases with T1 stage, 7 cases with T2 stage, 22 cases with T3 stage, and 6 cases with T4 stage by enhanced CT imaging with an accuracy of 75.00%; 6 cases with T1 stage, 7 cases with T2 stage, 22 cases with T3 stage, and 5 cases with T4 stage by ultrasonography examination, with an accuracy of 77.50%; and 4 cases with T1 stage, 10 cases with T2 stage, 19 cases with T3 stage, and 7 cases with T4 stage by both enhanced CT imaging and ultrasonography examination, with an accuracy of 85.00%. The accuracy of T staging in gastric carcinoma by both enhanced CT and ultrasound was higher than that either by enhanced CT or by ultrasound, respectively (P < 0.05). The anastomosis degree of the gastric carcinoma between enhanced CT and ultrasonography was κ = 0.404.

Conclusions

Combination diagnosis of enhanced CT and oral contrast-enhanced ultrasonography is helpful to improve the accuracy of T staging of gastric carcinoma before operations.

Ultrasonographic imaging of inflammatory bowel disease in pediatric patients

Inflammatory bowel disease (IBD) is one of the most common chronic gastrointestinal diseases in pediatric patients. Choosing the optimal imaging modality for the assessment of gastrointestinal disease in pediatric patients can be challenging. The invasiveness and patient acceptance, the radiation exposure and the quality performance of the diagnostic test need to be considered. By reviewing the literature regarding imaging in inflammatory bowel disease the value of ultrasound in the clinical management of pediatric patients is highlighted. Transabdominal ultrasound is a useful, noninvasive method for the initial diagnosis of IBD in children; it also provides guidance for therapeutic decisions and helps to characterize and predict the course of the disease in individual patients. Ultrasound techniques including color Doppler imaging and contrast-enhanced ultrasound are promising imaging tools to determine disease activity and complications. Comparative studies between different imaging methods are needed.

Failure of gastroenterologists to apply intestinal ultrasound in inflammatory bowel disease in the Asia-Pacific: a need for action

Intestinal ultrasound (IUS) is a cheap, noninvasive, risk-free procedure that is significantly underutilized in the diagnosis and management of patients with inflammatory bowel disease (IBD) in the Asia-Pacific region. More cost-effective methods of monitoring disease activity are required in light of the increasing global burden of IBD (especially in Asia), the advent of personalized medicine, and the rising cost of healthcare. IUS is a prime example of a technique that meets these needs. Its common clinical applications include assessing the activity and complications of IBD. In continental Europe, countries such as Germany and Italy use this imaging tool as the standard of care and have integrated it into management protocols. There are formal training programs in these countries to train gastroenterologists in IUS, and it is used in an outpatient setting during patient consultations. Barriers to its use in the Asia-Pacific region include lack of experience and research data, and there are few established centers with active training programs. These concerns can be addressed by investing more in IUS service provision and by increasing allocation of resources toward local research and training. Increased uptake of IUS will ultimately benefit patients with IBD.

Contrast-enhanced ultrasound in the diagnosis of patients suspected of having active Crohn's disease: meta-analysis

This meta-analysis was aimed at assessing the performance of oral/microbubble contrast-enhanced ultrasound (CEUS) in the detection of active Crohn's disease (CD). A literature search of PubMed, Medline, the China National Knowledge Infrastructure and the Cochrane Library was conducted. Published articles that evaluated the diagnostic potency of CEUS in CD were included in the study. A total of eight articles, which included 428 patients, were finally analyzed. Sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and area under the curve were calculated to examine the diagnostic accuracy of CEUS. The pooled sensitivity and specificity of CEUS for active CD were 93% (95% confidence interval: 89%-95%) and 87% (81%-91%), respectively. The summary diagnostic odds ratio was 80.35 (30.93-208.73), and the area under the curve was 0.9633. In conclusion, this meta-analysis pooled results from previous studies to evaluate the accuracy of CEUS in the detection of CD. We found that CEUS has high accuracy in the detection of active CD using endoscopy/biopsy or clinical index as the reference standard. In the future, CEUS may also be widely used in other diseases, reducing the necessity for invasive diagnostic procedure.

Small intestinal contrast ultrasonography for the detection of small bowel complications in Crohn's disease: correlation with intraoperative findings and magnetic resonance enterography

BACKGROUND AND AIMS

In evaluating small bowel Crohn's disease (CD), small intestine contrast-enhanced ultrasonography (SICUS) is emerging as an alternative to magnetic resonance enterography (MRE). This retrospective study compared the diagnostic accuracy of SICUS and MRE with surgical findings, and their level of agreement.

METHODS

We identified a cohort of CD patients investigated by either SICUS and/or MRE that subsequently required resective bowel surgery within 6 months. The accuracy and agreement of SICUS and MRE to detect small bowel complications were compared with intraoperative findings using kappa coefficient (κ). Agreement between SICUS and MRE in those undergoing both modalities was also assessed.

RESULTS

A total of 67 patients were evaluated; 25 underwent SICUS and 17 underwent MRE prior to surgery. Another 25 patients underwent both SICUS and MRE. When compared with intraoperative findings, the sensitivity of SICUS and MRE was 87.5% and 100%, respectively, in detecting strictures, 87.7% and 66.7% for fistulae, 100% for both in identifying abscesses, 100% and 66.7% for bowel dilatation, and 94.7% and 81.8% in defining bowel wall thickening. When correlating SICUS and MRE with surgery, there was a high level of agreement in localizing strictures (κ = 0.75, 0.88, respectively), fistulae (κ = 0.82, 0.79) and abscesses (κ = 0.87, 0.77). Concordance between SICUS and MRE was substantial or almost complete in identifying stricturing disease (κ = 0.84), their number and location (κ = 0.85), fistulae (κ = 0.65), and mucosal thickening (κ = 0.61).

CONCLUSION

SICUS accurately identified small bowel complications and correlated well with MRE and intraoperative findings. SICUS offers an alternative in the preoperative assessment of CD.

Imaging techniques in IBD and their role in follow-up and surveillance

The assessment of extent and severity of IBD is crucial for directing treatment decisions. Clinical symptoms alone are neither sensitive nor specific for the assessment of lesion severity in IBD. Cross-sectional imaging techniques, as well as small-bowel capsule endoscopy (SBCE) and device-assisted enteroscopy, have a high accuracy for assessing the extent of mucosal lesions, and are reliable alternatives to ileocolonoscopy. New endoscopic techniques and devices are emerging for improved follow-up and surveillance. In this Review, we discuss different imaging techniques that are used to assess IBD activity and to survey patients with IBD, and highlight the latest developments in each area. Moreover, technical improvements and new tools that aim to measure intestinal fibrosis, postoperative recurrence, activity indices and endoscopic features are analysed. All of these imaging techniques are aimed at changing the paradigm from symptom-driven to lesion-driven treatment of IBD.

Review article: optimal preparation for surgery in Crohn's disease

BACKGROUND

One-third of Crohn's disease (CD) patients will undergo abdominal surgery within the first 5 years of diagnosis.

AIM

To review the available evidence on pre-operative optimisation of CD patients.

METHODS

The literature regarding psychological support, radiological imaging, abdominal abscess management, nutritional support, thromboembolic prophylaxis and immunosuppression in the perioperative setting was reviewed.

RESULTS

For diagnosis of fistulas, abscesses and stenosis, ultrasonography (US), computed tomography (CT) and magnetic resonance imaging (MRI) have a high diagnostic accuracy. Under either CT or US guidance, it is possible to perform abscess percutaneous drainage (PD), which, with systemic antibiotic therapy, should be the first-line approach to intra-abdominal abscesses. CD patients with weight loss <10% within the last 3-6 months, body mass index < 18.5 kg/m(2) and/or albumin levels <30 g/L, are at an increased risk of post-operative complications. Pre-operative nutritional support should be used in these patients. IBD patients undergoing surgery have a higher risk of venous thromboembolic disease than patients with colorectal cancer, and current guidelines recommend that they should receive prophylaxis with heparin. Whether the use of anti-TNF agents before surgery increases the likelihood of post-operative complications, is the subject of much debate. To date, cumulative evidence from most studies (all retrospective) suggests that there is no such risk increment. Prospective studies are necessary to firmly establish this conclusion.

CONCLUSIONS

Preparation for surgery requires close interaction between surgeons, gastroenterologist, radiologists, psychologists and the patient. Correct pre-operative planning of surgical treatment has a major impact on the outcome of such treatment.

Ultrasonographic findings in Crohn's disease

In recent years transabdominal bowel sonography has become a first-line modality both in the diagnosis and in the follow-up of inflammatory bowel diseases, especially Crohn's disease, reaching values of sensitivity ranging from 84 to 93 %. In particular, its role is very useful in the early diagnosis of complications such as stenosis, phlegmons, abscesses and fistulae. According to the available literature the ability of US to provide information about disease activity is still under debate and further studies are necessary. In this regard, of fundamental importance is the use of additional techniques such as color- and power-Doppler and contrast-enhanced ultrasound. The purpose of this paper is to report the main sonographic intestinal and extraintestinal findings detectable in Crohn's disease.

Measuring disease activity in Crohn's disease: what is currently available to the clinician

Crohn’s disease (CD) is a chronic inflammatory bowel disease characterized by a relapsing-remitting clinical behavior and dominated by intestinal inflammation. Being a chronic disorder that with time develops into a disabling disease, it is important to monitor the severity of inflammation to assess the efficacy of medication, rule out complications, and prevent progression. This is particularly true now that the goals of treatment are mucosal healing and deep remission. Endoscopy has always been the gold standard for assessing mucosal activity in CD, but its use is limited by its invasiveness and its inability to examine the small intestine, proximal to the terminal ileum. Enteroscopy and the less invasive small bowel capsule endoscopy enable the small bowel to be thoroughly explored and scores are emerging for classifying small bowel disease activity. Cross-sectional imaging techniques (ultrasound, magnetic resonance, computed tomography) are emerging as valid tools for monitoring CD patients, assessing inflammatory activity in the mucosa and the transmucosal extent of the disease, and for excluding extra-intestinal complications. Neither endoscopy nor imaging are suitable for assessing patients frequently, however. Noninvasive markers such as C-reactive protein, and fecal biomarkers such as calprotectin and lactoferrin, are therefore useful to confirm the inflammatory burden of the disease and to identify patients requiring further investigations.

[Diagnostic options. Indications and validity]

BACKGROUND

A variety of diagnostic methods provide the necessary rational basis for diagnosis, assessment of disease activity and exclusion of possible complications for patients with inflammatory bowel disease (IBD).

AIM

Currently, a wide range of diagnostic methods is available and easily accessible. The clinical use of all these different methods is inherently possible. As there is no reference test for either diagnosis or monitoring of IBD, diagnostic techniques must be selected, applied and interpreted in an appropriate clinical context. The objective is to evaluate the clinical, laboratory and imaging techniques including ultrasound and endoscopy in different clinical situations.

RESULTS

In addition to clinical parameters, fecal calprotectin and abdominal ultrasound are helpful tools to assess the inflammatory activity. In patients with high inflammatory activity, a routine endoscopy is not beneficial. At best, endoscopy can be performed to document the extent of mucosal inflammation before initiating an intensified immunosuppressive therapy. Knowledge and experience in the management and treatment of IBD complications are critical in providing a rational use of specific diagnostic methods.

CONCLUSION

As a basic principle, the critical evaluation of diagnostic methods in patients with IBD is of great importance. Specific clinical situations require specific diagnostic techniques. Every diagnostic method performed should have a purpose.

Gastrointestinal ultrasound in neonates, infants and children

Today US plays an important and increasing role in the assessment of many, partially age-specific conditions in the GI tract in neonates, infants and children. Knowledge of the potential capabilities of US and its restrictions together with a skillful performance of GI US examination can provide essential anatomic and functional diagnostic information in many pediatric GI disorders. The aim of this review is to highlight the potential of ultrasound (US) in the evaluation of the gastrointestinal (GI) tract in neonates, infants and children. Basic and potential applications of modern US tools in pediatric GI tract are addressed, the GI US examination technique is discussed - including some common and/or typical clinical applications of and indications for US.

Temporal trends in imaging and associated radiation exposure in inflammatory bowel disease

OBJECTIVES

Increasing use of diagnostic imaging in inflammatory bowel disease (IBD) has led to concerns about the malignant potential of ionising radiation in a cohort that have an increased lifetime risk of gastrointestinal malignancy. The aim was to quantify radiation exposure in IBD patients referred from primary care, determine predictors of high exposure and evaluate temporal trends in diagnostic imaging over a 20-year period.

METHODS

This was a retrospective cohort study whereby IBD patients were recruited from the outpatient clinic and evaluated retrospectively. The total cumulative effective dose (CED) received from tests was calculated for each subject. Cox regression was performed to assess factors associated with potentially harmful levels of ionising radiation defined as total CED > 50 milli-sieverts (mSv; equivalent to five CT abdomen scans).

RESULTS

The cohort included 415 patients. Median total CED was 7.2 mSv (IQR: 3.0-22.7) in Crohn's disease and 2.8 mSv (IQR: 0.8-8.9) in ulcerative colitis patients, respectively. A total of 32 patients (8%) received a CED > 50 mSv. A history of IBD-related surgery was associated with high exposure (HR 7.7). During the study period, usage of abdominal CT increased by 310%.

CONCLUSION

Approximately 1 in 13 patients in the study cohort were exposed to potentially harmful levels of ionising radiation. Strategies to minimise exposure to diagnostic medical radiation in IBD patients are required.

Cross-sectional imaging modalities in Crohn's disease

The standard tools assessing the activity of Crohn's disease (CD) measure the severity of symptoms (the Crohn's Disease Activity Index) or the degree of endoscopic lesions (the Crohn's Disease Endoscopic Index of Severity, the Simplified Endoscopy Score), not the global bowel damage. It is necessary to find new instruments able to assess the structural and functional damage to the intestine and the progression over time. We reviewed recent publications on the accuracy of abdominal ultrasound (US), computed tomography enterography (CTE), and magnetic resonance imaging enterography (MRE) for the assessment of CD. US, CTE and MRE have been shown to have a high and comparable diagnostic accuracy for both the diagnosis and complications of CD, but US and MRE have the major advantage of not imparting ionizing radiation. In summary, findings from these imaging modalities with endoscopic lesions and surgical history incorporating into the Lémann score will allow measuring the global bowel damage at specific time and the progression of disease over time and assessing the impact of different strategies.

Small intestine contrast ultrasonography in pediatric Crohn's disease

OBJECTIVE

To evaluate the diagnostic accuracy of small intestine contrast ultrasonography (SICUS) in pediatric Crohn's disease (CD).

STUDY DESIGN

A total of 51 consecutive patients (median age 15 years; range 3-20, 31 male patients), 21 with suspected and 30 with proven CD, were studied. All patients underwent standard ultrasonography (ie, transabdominal ultrasonography [TUS]), SICUS, small bowel follow-through, and upper and lower endoscopy. SICUS was performed in patients after they ingested an oral contrast solution. TUS and SICUS were compared with small bowel follow-through and endoscopy via use of the final diagnosis as reference standard.

RESULTS

In undiagnosed patients, the sensitivity and specificity of TUS and SICUS in detecting CD small bowel lesions were 75% and 100% and 100% and 100%, respectively. In patients with proven CD, the sensitivity and specificity of TUS and SICUS were 76% and 100% and 96% and 100%, respectively. The agreement (k) with radiology for site of lesions was almost perfect for SICUS (0.93), both for jejunal and ileal lesions, and it was fair (0.40) for jejunal and substantial (0.68) for ileal lesions for TUS. Compared with radiology SICUS correctly assessed the length of lesions, whereas TUS underestimated it (P = .0001).

CONCLUSIONS

The radiation-free technique SICUS is comparable with radiology and more accurate than TUS in assessing small bowel lesions in pediatric CD, mainly in the detection of proximal small bowel disease.

Accuracy of small-intestine contrast ultrasonography, compared with computed tomography enteroclysis, in characterizing lesions in patients with Crohn's disease

BACKGROUND & AIMS

Small-intestine contrast ultrasonography (SICUS) is a radiation-free technique that can detect intestinal damage in patients with Crohn's disease (CD). We evaluated the diagnostic accuracy of SICUS in determining the site, extent, and complications of CD, compared with computed tomography (CT) enteroclysis as the standard.

METHODS

We performed a retrospective analysis of data from 59 patients with CD evaluated by SICUS and CT enteroclysis 3 months apart, between January 2007 and April 2012. We evaluated disease site (based on bowel wall thickness), extent of lesions, and presence of complications (stenosis, prestenotic dilation, abscess, or fistulas) using CT enteroclysis as the standard. Sensitivity, specificity, and diagnostic accuracy were calculated. We determined the correlations in maximum wall thickness and disease extent in the small bowel between results from SICUS and CT enteroclysis.

RESULTS

SICUS identified the site of small bowel CD with 98% sensitivity, 67% specificity, and 95% diagnostic accuracy; it identified the site of colon CD with 83% sensitivity, 97.5% specificity, and 93% diagnostic accuracy. Results from SICUS and CT enteroclysis correlated in determination of bowel wall thickness (rho, 0.79) and disease extent (rho, 0.89; P < .0001 for both). SICUS detected ileal stenosis with 95.5% sensitivity, 80% specificity, and 91.5% diagnostic accuracy, and prestenotic dilation with 87% sensitivity, 67% specificity, and 75% diagnostic accuracy. SICUS detected abscesses with 78% sensitivity, 100% specificity, and 97% diagnostic accuracy, and fistulas with 78.5% sensitivity, 95.5% specificity, and 91.5% diagnostic accuracy.

CONCLUSIONS

SICUS identified lesions and complications in patients with CD with high levels of sensitivity, specificity, and accuracy compared with CT enteroclysis. SICUS might be used as an imaging tool as part of a focused diagnostic examination of patients with CD.

Imaging techniques for assessment of inflammatory bowel disease: joint ECCO and ESGAR evidence-based consensus guidelines

The management of patients with IBD requires evaluation with objective tools, both at the time of diagnosis and throughout the course of the disease, to determine the location, extension, activity and severity of inflammatory lesions, as well as, the potential existence of complications. Whereas endoscopy is a well-established and uniformly performed diagnostic examination, the implementation of radiologic techniques for assessment of IBD is still heterogeneous; variations in technical aspects and the degrees of experience and preferences exist across countries in Europe. ECCO and ESGAR scientific societies jointly elaborated a consensus to establish standards for imaging in IBD using magnetic resonance imaging, computed tomography, ultrasonography, and including also other radiologic procedures such as conventional radiology or nuclear medicine examinations for different clinical situations that include general principles, upper GI tract, colon and rectum, perineum, liver and biliary tract, emergency situation, and the postoperative setting. The statements and general recommendations of this consensus are based on the highest level of evidence available, but significant gaps remain in certain areas such as the comparison of diagnostic accuracy between different techniques, the value for therapeutic monitoring, and the prognostic implications of particular findings.

Systematic review: MRI enterography for assessment of small bowel involvement in paediatric Crohn's disease

BACKGROUND

Barium meal enteroclysis (BM) is the recommended imaging technique for small bowel inaccessible by ileo-colonoscopy when diagnosing paediatric-onset inflammatory bowel disease, but it has poor sensitivity and involves ionising radiation. MRI enterography (MRE) is an alternative methodology.

AIMS

To critically appraise the published evidence on MRE in the assessment of Paediatric inflammatory bowel disease by systematic review.

METHODS

Review of all English language data reporting MRE for the investigation of patients <18 years with known or suspected IBD. Primary searches of Medline (Jan 1950-April 2012), Cinahl (1966-April 2012) and Pubmed (Jan 1950-April 2012) were performed using keyword and MeSH terms; IBD; Magnetic resonance imaging; small bowel imaging; EMBASE was then searched. Two authors independently assessed the quality of studies using the quality assessment of diagnostic accuracy studies tool.

RESULTS

Searches yielded 930 035 hits, combination word searches limited to 1983 titles. Fifty-two studies were fully reviewed, 41 were excluded due to lack of paediatric data. Eleven studies of 496 children were included. All studies used endoscopy as the reference test. 10/496 patients required jejunal intubation for bowel preparation. Meta-analysis of six comparable studies gave a pooled sensitivity and specificity for MRE detection of active terminal ileal Crohn's disease of 84% and 97% respectively. Studies displayed heterogeneity in bowel preparation, scanning technique, reporting methodology and timing of ileo-colonoscopy in relation to MRE. In three studies comparing BM, MRE had greater sensitivity and specificity.

CONCLUSIONS

MRE is a sensitive and specific tool for diagnosis in paediatric inflammatory bowel disease. Technical considerations require refinement and standardisation; however, MRE has no radiation. Current data suggest that MRE should supersede BM as the SB imaging technique in centres with appropriate expertise.

Imaging of pediatric patients with inflammatory bowel disease

OBJECTIVE

The goal of this review is to examine the current imaging literature and develop basic imaging guidelines for evaluation of children with inflammatory bowel disease (IBD). The three following typical clinical scenarios in the imaging evaluation of IBD are considered: patient with an initial diagnosis of suspected IBD, the goals being to determine disease extent and severity and to differentiate Crohn disease from ulcerative colitis; patient with known IBD presenting with new acute symptoms (fever, peritonitis, leukocytosis) requiring urgent evaluation; and patient with known IBD presenting with nonacute symptomatic recurrence (abdominal pain, diarrhea), the goals being to assess the efficacy of the current treatment and to evaluate the possible need for additional medical or surgical intervention.

CONCLUSION

Imaging of pediatric patients with IBD must balance considerations of diagnostic accuracy against concerns about patient exposure to ionizing radiation and tolerance of the imaging technique. The imaging modality chosen depends on the clinical presentation and expected pathologic finding.

Small intestine contrast ultrasonography vs computed tomography enteroclysis for assessing ileal Crohn's disease

AIM: To compare computed tomography enteroclysis (CTE) vs small intestine contrast ultrasonography (SICUS) for assessing small bowel lesions in Crohn's disease (CD), when using surgical pathology as gold standard.

METHODS: From January 2007 to July 2008, 15 eligible patients undergoing elective resection of the distal ileum and coecum (or right colon) were prospectively enrolled. All patients were under follow-up. The study population included 6 males and 9 females, with a median age of 44 years (range: 18-80 years). Inclusion criteria: (1) certain diagnosis of small bowel requiring elective ileo-colonic resection; (2) age between 18-80 years; (3) elective surgery in our Surgical Unit; and (4) written informed consent. SICUS and CTE were performed ≤ 3 mo before surgery, followed by surgical pathology. The following small bowel lesions were blindly reported by one sonologist, radiologist, surgeon and histolopathologist: disease site, extent, strictures, abscesses, fistulae, small bowel dilation. Comparison between findings at SICUS, CTE, surgical specimens and histological examination was made by assessing the specificity, sensitivity and accuracy of each technique, when using surgical findings as gold standard.

RESULTS: Among the 15 patients enrolled, CTE was not feasible in 2 patients, due to urgent surgery in one patients and to low compliance in the second patient, refusing to perform CTE due to the discomfort related to the naso-jejunal tube. The analysis for comparing CTE vs SICUS findings was therefore performed in 13 out of the 15 CD patients enrolled. Differently from CTE, SICUS was feasible in all the 15 patients enrolled. No complications were observed when using SICUS or CTE. Surgical pathology findings in the tested population included: small bowel stricture in 13 patients, small bowel dilation above ileal stricture in 10 patients, abdominal abscesses in 2 patients, enteric fistulae in 5 patients, lymphnodes enlargement (> 1 cm) in 7 patients and mesenteric enlargement in 9 patients. In order to compare findings by using SICUS, CTE, histology and surgery, characteristics of the small bowel lesions observed in CD each patient were blindly reported in the same form by one gastroenterologist-sonologist, radiologist, surgeon and anatomopathologist. At surgery, lesions related to CD were detected in the distal ileum in all 13 patients, also visualized by both SICUS and CTE in all 13 patients. Ileal lesions > 10 cm length were detected at surgery in all the 13 CD patients, confirmed by SICUS and CTE in the same 12 out of the 13 patients. When using surgical findings as a gold standard, SICUS and CTE showed the exactly same sensitivity, specificity and accuracy for detecting the presence of small bowel fistulae (accuracy 77% for both) and abscesses (accuracy 85% for both). In the tested CD population, SICUS and CTE were also quite comparable in terms of accuracy for detecting the presence of small bowel strictures (92% vs 100%), small bowel fistulae (77% for both) and small bowel dilation (85% vs 82%).

CONCLUSION: In our study population, CTE and the non-invasive and radiation-free SICUS showed a comparable high accuracy for assessing small bowel lesions in CD.

A phase 1 open-label trial shows that smad7 antisense oligonucleotide (GED0301) does not increase the risk of small bowel strictures in Crohn’s disease

BACKGROUND

In Crohn's disease (CD), knockdown of Smad7, an inhibitor of Transforming Growth Factor (TGF)-β1 activity, with a specific antisense oligonucleotide (GED0301) seems to be safe and tolerable and associates with TGF-β1-mediated suppression of inflammatory pathways.

AIM

Since TGF-β1 has pro-fibrogenic effects in many organs, we evaluated whether GED0301 treatment associates with the formation of small bowel strictures.

METHODS

Fifteen patients with active, inflammatory CD, receiving oral GED0301 once daily for 7 days, were monitored for the formation of small bowel strictures by Small Intestine Contrast Ultrasonography (SICUS). Serum basic fibroblast growth factor (bFGF) and human chitinase 3-like 1 (also known as YKL-40), two markers of CD-related intestinal strictures, and matrix metalloproteinases (MMP) and tissue inhibitor 1 of MMPs (TIMP1) were analysed at day 0 and day 180 by ELISA. Crohn's disease activity index (CDAI) changes were also monitored.

RESULTS

Fourteen patients completed the 6-month study; the remaining underwent intestinal resection for a severe relapse not responsive to medical treatment. No patient developed small bowel stricture and none experienced obstructive symptoms during the study period. GED0301 treatment induced no significant change in the circulating levels of bFGF, YKL-40, MMPs and TIMP1. Seven of 12 patients who reached clinical remission following GED0301 treatment maintained a CDAI < 150 at day 180.

CONCLUSION

Short-term treatment of patients with Crohn's disease using GED0301 is not associated with the development of small bowel stricture, thus reinforcing the concept that this drug is safe at least at early time points.

Crohn's disease: prevalence of intestinal and extraintestinal manifestations detected by computed tomography enterography with water enema

BACKGROUND

Computed tomography enterography (CTE) may detect the presence, severity, and extent of bowel inflammation in patients with Crohn's disease (CD). The aim of our study was to assess, among a cohort of 22 histologically proven CD patients, the prevalence of disease distribution, behavior, anastomotic recurrence and extraintestinal manifestations detected by an original CTE technique.

METHODS

Two radiologists reviewed 221 CTEs performed providing both small and large bowel distension by oral administration of neutral contrast material and trans-rectal introduction of a water enema (CTE-WE).

RESULTS

Ileal CD was detected in 116 CTE-WEs (52.4%), including 71/116 (61.2%) non-stricturing/non-penetrating, 17/116 (14.6%) stricturing, and 28/116 (24.1%) penetrating forms. Colonic CD was appreciable in 35 (15.8%) patients, including 18/35 (51.4%) non-stricturing/non-penetrating, 6/35 (17.1%) stricturing, and 11/35 (31.4%) penetrating forms. Ileocolic CD was present in 52 (23.5%) CTE-WEs, including 30/52 (57.7%) non-stricturing/ non-penetrating; 3/52 (5.7%) stricturing, and 19/52 (36.5%) penetrating forms. In 10/221 patients (4.5%), upper gastrointestinal involvement (UGI) was present. Perianal disease was observed in 17/221 patients (7.7%). Fistulas were present in 52 (23.5%) and abscesses in 24 (10.8%) CTE-WEs, respectively. Among 57/221 (25.8%) patients who had undergone a disease-related intestinal resection, in 30/57 cases (52.6%) CD recurrence at the anastomosis was present. 4/221 patients (1.8%) with a histologically confirmed intestinal neoplastic stenosis were observed. Sacroiliitis (24%) was found to be prevalent over hepatic steatosis (10.8%), cholelithiasis (8.6%), and nephrolithiasis (4%).

CONCLUSIONS

CTE-WE represents a comprehensive imaging technique which may demonstrate bowel inflammation and CD extraintestinal manifestations. A peculiar prevalence of UGI involvement and neoplastic strictures were observed. In our study the prevalence of sacroiliitis resulted higher than previously reported.

Radiation exposure in patients with inflammatory bowel disease--primum non nocere?

BACKGROUND

Patients with Inflammatory Bowel disease (IBD) are frequently exposed to diagnostic medical radiation for the diagnosis and evaluation of their disease. Despite increasing awareness of the potentially serious downstream effects, few studies have quantified radiation exposure in IBD patients.

METHODS

We conducted a retrospective review of 280 consecutive patients attending IBD clinics at our hospital. All incidences of diagnostic medical radiation from initial diagnosis until 30 June 2010 inclusive were recorded. The radiation dose for each procedure was obtained from standardized tables and the effective dose for each procedure calculated by multiplying this value by the number of procedures during the study period. The sum of doses received was the cumulative effective dose.

RESULTS

The mean and median cumulative effective radiation doses were 10.17 mSv and 4.12 mSv respectively. Crohn's disease patients had significantly higher cumulative effective radiation exposure than UC patients (p < 0.001) with exposure exceeding 10 mSv in 58.3%, 25 mSv in 18.1% and 50 mSv in 6.3%, respectively. Smoking status, disease duration, and previous surgery were significant predictors for increased radiation exposure even after adjusting for other predictors. 47 small bowel magnetic resonance (MR) studies were undertaken as an alternative to ionising radiation in the last 3 years.

CONCLUSIONS

Patients with IBD, particularly those with Crohn's disease, are exposed to significant amounts of diagnostic medical radiation in their lifetime. Clinicians must remain vigilant to the risk of cumulative radiation when evaluating these patients and consider non-ionizing alternatives such as intestinal ultrasound and MR imaging where clinically appropriate.

Development of a numerical index quantitating small bowel damage as detected by ultrasonography in Crohn's disease

Small intestine contrast ultrasonography (SICUS) has emerged as a valuable tool in the detection of intestinal damage in Crohn's disease (CD). Our aim was to develop a numerical index quantitating small bowel damage as detected by SICUS in patients with an established diagnosis of CD. One hundred and ten patients with ileal or ileocolonic CD were prospectively enrolled and followed up for one year. Disease activity was assessed by CDAI and CRP levels. Study variables included bowel wall thickness, lumen diameter, lesion length and number of lesion site. Fistula, mesenteric adipose tissue alteration, abscess and lymphnodes were also considered. Bowel segments were considered as a hollow cylinder. Standardized variations of variables were combined into a statistical and mathematical model to create an algorithm scoring an index value ranging from 0 to 200. Index was subdivided into a severity scale with 5 classes from the lower (A) to the higher score (E). Median lesion index value was significantly higher (p<0.005) in patients with a CDAI>150 and in patients with CRP>5 mg/l (p=0.003). Patients classified in class E and D at SICUS underwent surgery within one year follow up more frequently than those in class C, B and A (p<0.0001). We propose a new index for assessment of small bowel lesions in CD (SLIC: sonographic lesion index for CD) developed by using SICUS. This index may turn ultrasonography in CD from a descriptive qualitative assessment to a quantitative numerical index suitable for comparison studies.

Investigation of small bowel in pediatric Crohn's disease

Investigation of the small bowel has been traditionally a challenge for pediatric gastroenterologists due to its location, anatomical tortuosity, and invasiveness of the available techniques. Recently, there has been a remarkable improvement in imaging and endoscopic tools aimed at exploring successfully the small intestine in inflammatory bowel disease. The former are represented by ultrasonography (either alone or with administration of oral contrast agents) and by magnetic resonance: both have provided accurate methods to detect structural bowel changes, diminishing patient discomfort and precluding radiation hazard. The use of traditional radiologic techniques such as fluoroscopy have been markedly reduced due to radiation exposure and inability to depict transmural inflammation or extraluminal complications. Among the novel endoscopic tools, capsule endoscopy and balloon-assisted enteroscopy have tremendously opened new diagnostic and therapeutic perspectives, by allowing the direct visualization of small intestinal mucosa and, through enteroscopy, histological diagnosis as well as therapeutic interventions such as stricture dilation and bleeding treatment. These endoscopic techniques should always be preceded by imaging of the intestine in order to identify strictures. This review describes the most recent progress with the employment of novel imaging and endoscopic methodologies for investigating the small bowel in children with suspected or established Crohn's disease.

Optimal assessment of paediatric IBD with MRI and barium follow-through

OBJECTIVES

The present UK criterion standard for assessing children with suspected inflammatory bowel disease (IBD) is upper endoscopy, ileocolonoscopy, and barium follow-through (BaFT). Significant doses of radiation, unpalatable contrast, and volume intolerance are involved with BaFT. Practice in investigating Crohn disease (CD) is changing with the increasing use of magnetic resonance imaging (MRI). The aim of the present study was to compare BaFT and a new abdominal MRI protocol in a paediatric IBD population.

METHODS

All consecutive patients with a new diagnosis of IBD or requiring reassessment from September 2008 to December 2010 were investigated with both abdominal MRI and BaFT in accordance with a specific local paediatric IBD protocol. The studies were reported by nonblinded radiologists with an interest in gastrointestinal imaging. The reports were compared in conjunction with case note review.

RESULTS

Eighty-seven patients underwent both BaFT and MRI abdomen. Thirty-one percent of patients had additional pathology on MRI, not seen on the BaFT. Sixty-seven percent of patients (n=59) had an MRI finding equivalent to BaFT. Using histology as a criterion standard for detecting terminal ileal disease, BaFT had a sensitivity and specificity of 76% and 67%, and MRI had a sensitivity and specificity of 83% and 95%, respectively.

CONCLUSIONS

This is the largest series of small bowel MRI in a paediatric population. MRI reports were at least equivalent to BaFT. MRI had higher sensitivity and, particularly, specificity in detecting terminal ileal pathology. These findings suggest that MRI should become the criterion standard investigation in children with IBD in centres with appropriate expertise, with zero radiation exposure being highly advantageous.

Imaging modalities for the noninvasive assessment of fibrosis in Crohn's disease

The development of strictures in Crohn's disease is a main cause of hospitalization and often represent an indication for surgery. The differentiation between inflammatory and fibrotic strictures is useful to determine the optimal treatment. Today, the availability of noninvasive methods to assess the presence and extension of strictures offers new tools for the diagnosis and follow-up of the disease. Bowel ultrasound, power doppler ultrasound, contrast-enhanced ultrasound, magnetic resonance imaging offer the additional advantage that they do not expose patients to ionizing radiation. In this paper we provide an update on the accuracy of these noninvasive methods for the diagnosis of Crohn's disease.

Meta-analysis: diagnostic medical radiation exposure in inflammatory bowel disease

BACKGROUND

Diagnostic imaging plays a pivotal role in the diagnosis and management of inflammatory bowel disease (IBD); however, increasing use has led to concerns about the malignant potential of ionising radiation. Several studies have demonstrated that diagnostic imaging can result in exposure to potentially harmful levels of ionising radiation in IBD patients.

AIM

To determine the pooled prevalence of increased exposure and pooled odds ratio of risk factors associated with exposure to potentially harmful levels of diagnostic medical radiation.

METHODS

We searched Medline, EMBASE, CINHAL and reference lists of identified articles, without language restrictions in October 2011.

RESULTS

Six studies with 1704 participants provided data on the proportion of patients receiving potentially harmful levels of radiation defined as ≥50 milli-sieverts (mSv)-equivalent to 5 CT abdomen scans. The pooled prevalence was 8.8% (95% CI 4.4-16.8) for IBD patients and 11.1% (95% CI 5.7-20.5%) and 2% (95% CI 0.8-4.9%) for Crohn's disease and ulcerative colitis patients respectively. Five studies involving 2627 participants provided data for risk factors. IBD-related surgery and corticosteroid use were significant with pooled adjusted odds ratio of 5.4 (95% CI 2.6-11.2) and 2.4 (95% CI 1.7-3.4) respectively.

CONCLUSIONS

About 1 in 10 patients may be exposed to potentially harmful levels of diagnostic medical radiation. Corticosteroid use and IBD related surgery increased this risk. Strategies to reduce radiation exposure while assessing disease activity need to be considered.