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

Ultrasound of the small bowel in Crohn's disease

Several radiological and endoscopic techniques are now available for the study of inflammatory bowel diseases. In everyday practice, the choice of the technique to be used depends upon its availability and a careful evaluation of diagnostic accuracy, clinical usefulness, safety, and cost. The recent development of innovative and noninvasive imaging techniques has led to a new and exciting area in the exploration of the gastrointestinal tract, especially in Crohn's disease patients by using ultrasound with oral or intravenous contrast.

Crohn's disease imaging: a review

Crohn's disease is a chronic granulomatous inflammatory disease of the gastrointestinal tract, which can involve almost any segment from the mouth to the anus. Typically, Crohn's lesions attain segmental and asynchronous distribution with varying levels of seriousness, although the sites most frequently involved are the terminal ileum and the proximal colon. A single gold standard for the diagnosis of CD is not available and the diagnosis of CD is confirmed by clinical evaluation and a combination of endoscopic, histological, radiological, and/or biochemical investigations. In recent years, many studies have been performed to investigate the diagnostic potential of less invasive and more patient-friendly imaging modalities in the evaluation of Crohn's disease including conventional enteroclysis, ultrasonography, color-power Doppler, contrast-enhanced ultrasonography, multidetector CT enteroclysis, MRI enteroclysis, and 99mTc-HMPAO-labeled leukocyte scintigraphy. The potential diagnostic role of each imaging modality has to be considered in different clinical degrees of the disease, because there is no single imaging technique that allows a correct diagnosis and may be performed with similar results in every institution. The aim of this paper is to point out the advantages and limitations of the various imaging techniques in patients with suspected or proven Crohn's disease.

Small intestine contrast ultrasonography (SICUS) for the detection of small bowel complications in crohn's disease: a prospective comparative study versus intraoperative findings

BACKGROUND

In Crohn's disease (CD) patients, small intestine contrast ultrasonography (SICUS) accurately assesses small bowel lesions. Its diagnostic role is not known in the assessment of intraabdominal CD complications. The aim was to assess the value of SICUS to detect intestinal complications in patients with CD.

METHODS

Forty-nine CD patients (21 female, mean age 37.7 years; range 12-78 years) underwent resective bowel surgery and were included in this study. The accuracy of SICUS to preoperatively detect number, site, and length of strictures, fistulas, and abscesses was compared with surgical and pathological findings by kappa statistics.

RESULTS

SICUS identified at least one stricture in 39/40 and excluded it in 9/9 (97.5% sensitivity, 100% specificity, k = 0.93); two or more strictures in 9/12 (75% sensitivity, 100% specificity, k = 0.78). The agreement by k-statistics between SICUS and surgery in identifying proximal and distal small intestine site of stricture was 1 and 0.92, respectively. The extension of strictures was 6.8 ± 5.4 cm at surgery, 6.6 ± 5.4 cm at SICUS (NS). Fistulas were correctly identified in 27/28 patients and excluded in 19/21 patients (96% sensitivity, 90.5% specificity, k = 0.88). Intraabdominal abscesses were correctly detected in 10/10 patients and excluded in 37/39 patients (100% sensitivity, 95% specificity, k = 0.89).

CONCLUSIONS

SICUS is an accurate method for the detection of small intestinal complications in CD. Noninvasive SICUS is valuable as a primary investigative method for evaluating and planning proper treatment in patients with severe CD of the small bowel.

Diagnostic accuracy of small intestine ultrasonography using an oral contrast agent in Crohn's disease: comparative study from the UK

AIM

To evaluate the usefulness of small intestine contrast-enhanced ultrasonography (SICUS) using an oral contrast agent in routine clinical practice by assessing the level of agreement with the established techniques, small bowel follow-through (SBFT) and computed tomography (CT), and diagnostic accuracy compared with the final diagnosis in the detection of small bowel Crohn's disease (CD) and luminal complications in a regional centre.

MATERIALS AND METHODS

All symptomatic known or suspected cases of CD who underwent SICUS were retrospectively reviewed. The level of agreement between SICUS and SBFT, CT, histological findings, and C-reactive protein (CRP) level was assessed using kappa (κ) coefficient. Sensitivity was demonstrated using the final diagnosis as the reference standard defined by the outcome of clinical assessment, follow-up, and results of investigations other than SICUS.

RESULTS

One hundred and forty-three patients underwent SICUS of these 79 (55%) were female. Eighty-six (60%) were known to have CD and 57 (40%) had symptoms suggestive of intestinal disease with no previous diagnosis. Forty-six (55%) of the known CD patients had had at least one previous surgical resection. The sensitivity of SICUS in detecting active small bowel CD in known CD and undiagnosed cases was 93%. The kappa coefficient was 0.88 and 0.91 with SBFT and CT, respectively. SICUS detected nine patients who had one or more small bowel strictures and six patients with a fistula all detected by SBFT or CT.

CONCLUSION

SICUS is not only comparable to SBFT and CT but avoids radiation exposure and should be more widely adopted in the UK as a primary diagnostic procedure and to monitor disease complications in patients with CD.

Sonography of the small bowel after oral administration of fluid: an assessment of the diagnostic value of the technique

PURPOSE

This study was performed to assess the feasibility and possible advantages of bowel sonography after fluid filling of intestinal loops compared with conventional sonography.

MATERIALS AND METHODS

Forty-five consecutive patients with known or suspected coeliac disease (35 females, ten males; age range 11-65 years) prospectively underwent sonography before and after ingestion of 750 ml of an aqueous solution of polyethylene glycol. Results before and after fluid distension were compared to assess whether luminal filling improved small-bowel visualisation.

RESULTS

Luminal filling improved visualisation of intestinal features (luminal diameter, mucosal folds, parietal layers) in 77.6% of cases (marked, moderate or mild improvement in 2, 16 and 17 patients; 4.4%, 35.5% and 37.7%), respectively, and showed no change or worsening in 20% and 2.2% nine and one patient), respectively. Baseline examination showed abnormal features in 13/25 celiac patients (dilated fluid-filled loops, increased peristalsis, transient intussusception, mesenteric lymph nodes, intraperitoneal fluid). Reexamination after luminal filling showed additional abnormalities in six of the previous 13 and in three further coeliac patients. There were no false positive signs due to fluid administration.

CONCLUSIONS

Luminal filling can improve visualisation of bowel walls and fold pattern and may be helpful in selected cases.

Gastroenterology review and perspective: the role of cross-sectional imaging in evaluating bowel damage in Crohn disease

OBJECTIVE

This article will review the performance and limitations of cross-sectional imaging methods to detect and display critical features of Crohn disease (CD)-related bowel damage, including stenosis and penetrating complications (i.e., fistula, abscess). International efforts to incorporate cross-sectional imaging findings along with endoscopic and surgical findings to create a global bowel damage score over the length of the gastrointestinal tract are summarized along with the rationale for these efforts.

CONCLUSION

The first digestive damage score, the Lémann score, will incorporate surgical history, endoscopic findings, and imaging findings of stenosis and penetrating complications to provide a global assessment of CD-related destruction of the gastrointestinal tract. It is anticipated that the score will permit better understanding of the impact of modern therapeutics on the natural history of CD. Because CT is a technique that involves ionizing radiation and accuracy of ultrasound is highly related to CD location, MRI is proposed as first choice for nonemergent follow-up of CD patients.

Noninvasive imaging of the small bowel in Crohn's disease: the final frontier

The substantial morbidity and mortality associated with Crohn's disease underlines the importance of accurate assessment at presentation, during follow-up, when investigating complications, and when evaluating the response to therapeutic interventions. Accurate methods are required to quantify the severity and extent of disease.

Diagnostics in inflammatory bowel disease: Ultrasound

Diagnosis of chronic inflammatory bowel diseases (IBD) is based on a combination of clinical symptoms, laboratory tests and imaging data. Imaging of the morphological characteristics of IBD includes the assessment of mucosal alterations, transmural involvement and extraintestinal manifestations. No single imaging technique serves as a diagnostic gold standard to encompass all disease manifestations. Ultrasound, computed tomography (CT) or magnetic resonance imaging (MRI) allow cross-sectional imaging of the transmural alterations and extraintestinal manifestations. While in the USA the technique of choice is CT, in Europe the focus is more on MRI and ultrasound (US). Most patients with chronic IBD are diagnosed at a young age. After baseline diagnosis many of these young patients have to undergo repetitive imaging procedures during the variable clinical course of the disease, characterized by alternate periods of remission and active disease, and in monitoring the response to treatment. US has the advantage of being noninvasive, less costly, and easily repeatable, and thus can be very useful in following up patients with IBD. In addition, rising concern about radiation exposure in young adults indicates the demand for radiation-sparing techniques like US and MRI. This article focuses on the current clinical practice of US in IBD, describing the current technologies used in transabdominal intestinal US and the characteristic sonographic findings in Crohn´s disease and ulcerative colitis.

Systematic review: the use of ultrasonography, computed tomography and magnetic resonance imaging for the diagnosis, assessment of activity and abdominal complications of Crohn's disease

BACKGROUND

Cross-sectional imaging techniques, including ultrasonography (US), computed tomography (CT) and magnetic resonance imaging (MRI), are increasingly used for evaluation of Crohn's disease (CD). Aim  To perform an assessment of the diagnostic accuracy of cross-sectional imaging techniques for diagnosis of CD, evaluation of disease extension and activity and diagnosis of complications, and to provide recommendations for their optimal use.

METHODS

Relevant publications were identified by literature search and selected based on predefined quality parameters, including a prospective design, sample size and reference standard. A total of 68 publications were chosen.

RESULTS

Ultrasonography is an accurate technique for diagnosis of suspected CD and for evaluation of disease activity (sensitivity 0.84, specificity 0.92), is widely available and non-invasive, but its accuracy is lower for disease proximal to the terminal ileum. MRI has a high diagnostic accuracy for the diagnosis of suspected CD and for evaluation of disease extension and activity (sensitivity 0.93, specificity 0.90), and is less dependent on the examiner and disease location compared with US. CT has a similar accuracy to MRI for assessment of disease extension and activity. The three techniques have a high accuracy for identification of fistulas, abscesses and stenosis (sensitivities and specificities >0.80), although US has false positive results for abscesses. As a result of the lack of radiation, US or MRI should be preferred over CT, particularly in young patients.

CONCLUSIONS

Cross-sectional imaging techniques have a high accuracy for evaluation of suspected and established CD, reliably measure disease severity and complications; they may offer the possibility to monitor disease progression.

Development of the Crohn's disease digestive damage score, the Lémann score

Crohn's disease (CD) is a chronic progressive destructive disease. Currently available instruments measure disease activity at a specific point in time. An instrument to measure cumulative structural damage to the bowel, which may predict long-term disability, is needed. The aim of this article is to outline the methods to develop an instrument that can measure cumulative bowel damage. The project is being conducted by the International Program to develop New Indexes in Crohn's disease (IPNIC) group. This instrument, called the Crohn's Disease Digestive Damage Score (the Lémann score), should take into account damage location, severity, extent, progression, and reversibility, as measured by diagnostic imaging modalities and the history of surgical resection. It should not be "diagnostic modality driven": for each lesion and location, a modality appropriate for the anatomic site (for example: computed tomography or magnetic resonance imaging enterography, and colonoscopy) will be used. A total of 24 centers from 15 countries will be involved in a cross-sectional study, which will include up to 240 patients with stratification according to disease location and duration. At least 120 additional patients will be included in the study to validate the score. The Lémann score is expected to be able to portray a patient's disease course on a double-axis graph, with time as the x-axis, bowel damage severity as the y-axis, and the slope of the line connecting data points as a measure of disease progression. This instrument could be used to assess the effect of various medical therapies on the progression of bowel damage.

Small bowel capsule endoscopy vs conventional techniques in patients with symptoms highly compatible with Crohn's disease

BACKGROUND & AIMS

The diagnostic role of Small Bowel Capsule Endoscopy (SBCE) in Crohn's Disease (CD) is under investigation. In a prospective study we investigated the diagnostic role of SBCE in patients with symptoms highly compatible with CD and undefined diagnosis after conventional techniques.

METHODS

From September 2005 to May 2009, all patients with clinically suspected CD and not conclusive diagnosis after Ileocolonoscopy (IC), Small Bowel Follow Through (SBFT) and Small Intestine Contrast Ultrasonography (SICUS) were enrolled. Findings compatible with CD included: bowel wall thickness (BWT) >3mm (for SICUS), ulcers, stenosis/strictures, fistulae (for SICUS, SBFT); >5 aphtoid ulcers, deep ulcers and/or strictures (for SBCE).

RESULTS

Conventional techniques did not lead to a conclusive diagnosis in 30 patients (19 F, median age 31 years, range 8-57), showing chronic diarrhoea (n=27), abdominal pain (n=23), weight loss (n=5), fever (n=5), Iron Deficiency Anaemia (IDA)(n=5) and/or perianal disease (n=4). Findings compatible but not diagnostic for small bowel CD were detected in 19 (63%) by IC in 12 (40%) by SICUS and in 15 (50%) by SBFT. SBCE showed ileal lesions in 15 (50%) patients, including findings compatible with CD in 12 (40%). SBCE retention requiring surgery was observed in 1 patient. A significant concordance was observed between SBCE and IC k=0.33 C(k)=[0.25;0.42], but not between SBCE and SICUS k=0.13 IC(k)=[0.045;0.22] and between SBCE and SBFT k=0 IC(k)=[-0.089;0.089].

CONCLUSIONS

SBCE may detect lesions compatible with small bowel CD in almost one third of patients with symptoms highly compatible with CD and not conclusive diagnosis by using conventional techniques.

[Imaging of the small intestine: current knowledge]

Imaging of the small intestine is most challenging in daily routine. With endoscopy (including balloon enteroscopy) and modern high resolution imaging methods, e.g., ultrasound (US), magnetic resonance imaging (MRI) and computed tomography (CT), the gastroenterologist has ideal complementary methods available. Radiation exposure has to be kept in mind using CT and conventional X-ray-techniques. Therefore, most importantly ultrasound and MRI have changed the routine diagnostics of intestinal diseases. The three methods are not only assessing the lumen but similarly important also the wall and the surrounding structures of the small intestine. Furthermore functional processes can be visualized and provide important information about passage and perfusion which is mainly true for the real-time technique ultrasound. Balloon enteroscopy is the method of choice to examine the mucosa and luminal aspects and to achieve histological proven diagnosis by biopsy. The future role of capsule techniques has not yet been determined. This article addresses the endoscopist, radiologists and ultrasonographer interested in small intestinal disease. The authors give an overview of the actual significance of each method imaging the small intestine. After comments on the methods the typical indications are discussed.

Endoscopic vs ultrasonographic findings related to Crohn's disease recurrence: a prospective longitudinal study at 3 years

BACKGROUND AND AIMS

Ileocolonoscopy (IC) is the gold standard for assessing Crohn's Disease (CD) recurrence after ileo-colonic resection. In a prospective longitudinal study we compared findings related to CD recurrence when using techniques visualizing either the luminal or the extraluminal surface (IC and small bowel follow through, SBFT vs Small Intestine Contrast Ultrasonography, SICUS).

METHODS

From 2003 to 2008, 25 CD patients undergoing ileo-colonic resection were enrolled. Clinical assessment (CDAI) was performed at 1, 2 and 3 years. IC was performed at 1 (n=25) and 3 years (n=15), SBFT at 2 years (n=21) and SICUS at 1 (n=25), 2 (n=21) and 3 years (n=15). Recurrence was assessed by SBFT and SICUS (bowel wall thickness, BWT) when using IC as gold standard.

RESULTS

At 1 year, all patients were inactive and recurrence was detected by IC in 24/25 (96%) and by SICUS in 25/25 patients. At 2 years, 6/21 patients (29%) were active and recurrence was detected by SBFT in 12/21 (57%) and by SICUS in 21/21 patients. At 3 years, 5/15 patients (33%) were active, IC showed recurrence in 14/15 (93%), and SICUS in 15/15 patients. The endoscopic score at 1 year was higher in patients developing relapse at 2 years (n=5) than in patients maintaining remission (n=10) (median: 4, range 3-4 vs 2, range 0-3; p=0.003). The same finding was not observed by using SICUS (median BWT at 1 year: 5, range 4-7 vs 3.7, range 3.5-6; p=0.19).

CONCLUSIONS

Although IC and SICUS provide a different view of the bowel wall, in experienced hands SICUS provides findings compatible with endoscopic recurrence after ileo-colonic resection for CD. Discrepant findings may be observed in a low proportion of patients with minor lesions related to CD recurrence.

Wireless capsule endoscopy and proximal small bowel lesions in Crohn’s disease

AIM: To investigate the prevalence of proximal small bowel (SB) lesions detected by wireless capsule endoscopy (WCE) in Crohn’s disease (CD).

METHODS: WCE was performed in 64 patients: 32 with CD of the distal ileum, and 32 controls with iron-deficiency anemia (IDA) or diarrhea. WCE was performed using the Given SB-WCE, followed by small intestine contrast ultrasonography (SICUS). Findings compatible with CD by using WCE included erosions, aphthoid or deep ulcers, and strictures/stenosis.

RESULTS: WCE detected proximal SB lesions in 16/32 (50%) patients (14 aphthoid ulcers, 2 deep ulcers, one stricture), which appeared not to be related to clinical parameters [epigastric pain, age, smoking, non-steroidal anti-inflammatory drugs (NSAIDs), IDA]. Among patients with proximal SB lesions, 6 (37%) were smokers, 3 (19%) NSAID users, 3 (19%) had epigastric pain and 4 (25%) had IDA. SICUS detected proximal SB lesions in 3/32 patients (19%) also showing lesions with WCE. No correlations were observed between proximal SB lesions assessed by WCE or by SICUS (χ² = 1.5, P = 0.2).

CONCLUSION: The use of WCE allows the detection of previously unknown upper SB lesions in a high proportion of patients with a previous diagnosis of CD involving the distal ileum.

New pathophysiological insights and modern treatment of IBD

Inflammatory bowel disease (IBD), which comprises two main types, namely, Crohn's disease and ulcerative colitis, affects approximately 3.6 million people in the USA and Europe, and an alarming rise in low-incidence areas, such as Asia, is currently being observed. In the last decade, spontaneous mutations in a diversity of genes have been identified, and these have helped to elucidate pathways that can lead to IBD. Animal studies have also increased our knowledge of the pathological dialogue between the intestinal microbiota and components of the innate and adaptive immune systems misdirecting the immune system to attack the colon. Present-day medical therapy of IBD consists of salicylates, corticosteroids, immunosuppressants and immunomodulators. However, their use may result in severe side effects and complications, such as an increased rate of malignancies or infectious diseases. In clinical practice, there is still a high frequency of incomplete or absent response to medical therapy, indicating a compelling need for new therapeutic strategies. This review summarizes current epidemiology, pathogenesis and diagnostic strategies in IBD. It also provides insight in today's differentiated clinical therapy and describes mechanisms of promising future medicinal approaches.

Ultrasound and inflammatory bowel disease

Transabdominal bowel sonography is a fast, efficient, and cheap way of examining the intestines. It is also virtually hazard-free and well accepted by patients. During the last 20 years, it has been established as a procedure for detecting bowel disease early in the diagnostic workup. Although rather unspecific, the method is sensitive for detection of bowel disease and can be applied to find the extent and location of inflammatory bowel disease. In patients with known ulcerative colitis and Crohn disease, it can also be used for follow-up because it is easily repeatable and radiation-free. Because it can be applied to find both intraluminal and peri-intestinal pathological features, it is a particularly valuable tool for the detection of complications of Crohn disease as stenosis, fistulas, and abscesses. Neither B-mode nor Doppler techniques have been proven obviously useful in categorizing disease activity, but new techniques using intravenous contrast might come closer to solving this question. Finally, recent longitudinal studies using transabdominal bowel sonography show that it can also give important prognostic information and be used for monitoring the effect of therapy.

Magnetic resonance enterography in Crohn’s disease: Standard and advanced techniques

Crohn’s disease (CD) is a chronic autoimmune disorder that affects mainly young people. The clinical management is based on the Crohn’s Disease Activity Index and especially on biologic parameters with or without additional endoscopic and imaging procedures, such as barium and computed tomography examinations. Recently, magnetic resonance (MR) imaging has been a promising diagnostic radiologic technique with lack of ionizing radiation, enabling superior tissue contrast resolution due to new pulse-sequence developments. Therefore, MR enterography has the potential to become the modality of choice for imaging the small bowel in CD patients.

Severity of postoperative recurrence in Crohn's disease: correlation between endoscopic and sonographic findings

BACKGROUND

Crohn's disease (CD) recurrence is currently assessed by ileocolonoscopy. Small intestine contrast ultrasonography (SICUS) visualizes the small bowel lesions in CD, although its role after curative resection is undefined. We aimed to investigate the accuracy of SICUS in assessing CD recurrence after ileocolonic resection when using ileocolonoscopy as a gold standard. The correlation between the bowel wall thickness (BWT) measured by SICUS and the endoscopic score of recurrence was also assessed.

METHODS

The analysis included 72 CD patients with ileocolonic resection requiring ileocolonoscopy, undergoing SICUS within 6 months. Recurrence was assessed by ileocolonoscopy using the Rutgeerts' score. SICUS was performed after PEG ingestion and findings compatible with recurrence included: increased BWT (>3 mm), bowel dilation (>25 mm) or stricture (<10 mm).

RESULTS

Ileocolonoscopy detected recurrence in 67/72 (93%) patients. SICUS detected findings compatible with recurrence in 62/72 (86%) patients (5 false negative (FN), 4 false positive (FP), 1 true negative (TN), 62 true positive (TP)), showing a 92.5% sensitivity, 20% specificity, and 87.5% accuracy for detecting CD recurrence. The BWT detected by SICUS was correlated with the Rutgeerts' score (P = 0.0001; r = 0.67). The median BWT, the extent of the ileal lesions, and the prestenotic dilation were higher in patients with an endoscopic degree of recurrence >or=3 versus <or=2 (P < 0.001) and the lumen diameter was lower in patients with a Rutgeerts' score >or=3 versus <or=2 (P < 0.0001).

CONCLUSIONS

: Although SICUS and ileocolonoscopy provide different views of the small bowel, SICUS shows a significant correlation with the endoscopic findings. SICUS may represent an alternative noninvasive technique for assessing CD recurrence after ileocolonic resection.

Hydrosonography of the gastrointestinal tract

OBJECTIVE

Bowel sonography has become accepted as a useful tool in several gastrointestinal disorders. Filling of the gut with echo-poor liquids has been proposed to achieve a detailed evaluation of the bowel. This article refers to a review made concerning the benefits and limits of hydrosonography of the gastrointestinal tract.

CONCLUSION

The use of a luminal contrast agent in bowel sonography may improve results but should be adopted on a case-by-case basis, according to the clinical context and the experience of the sonologist.

Sonographic assessments of gastrointestinal and biliary functions

Ultrasound has been established as a routine work-up imaging method in abdominal diseases. It assesses the morphology of intra-abdominal organs and depicts the normal and pathological anatomy of the gastrointestinal tract as well as of the biliopancreatic system. Ultrasound is the method of choice for visualisation of motion sequences since it is, in contrast to other imaging methods, a real-time method. The non-invasiveness and the repeatability of the method are important advantages when performing investigations of functional processes. Therefore, ultrasound is most suited for functional studies. Up to now, functional ultrasound and its potential have been undervalued. Functional ultrasound provides a widely available method to increase our understanding of functional processes and motility. The authors review the options of functional ultrasound and discuss its practical relevance.

Sonography of the small intestine

In the last two decades, there has been substantial development in the diagnostic possibilities for examining the small intestine. Compared with computerized tomography, magnetic resonance imaging, capsule endoscopy and double-balloon endoscopy, ultrasonography has the advantage of being cheap, portable, flexible and user- and patient-friendly, while at the same time providing the clinician with image data of high temporal and spatial resolution. The method has limitations with penetration in obesity and with intestinal air impairing image quality. The flexibility ultrasonography offers the examiner also implies that a systematic approach during scanning is needed. This paper reviews the basic scanning techniques and new modalities such as contrast-enhanced ultrasound, elastography, strain rate imaging, hydrosonography, allergosonography, endoscopic sonography and nutritional imaging, and the literature on disease-specific findings in the small intestine. Some of these methods have shown clinical benefit, while others are under research and development to establish their role in the diagnostic repertoire. However, along with improved overall image quality of new ultrasound scanners, these methods have enabled more anatomical and physiological changes in the small intestine to be observed. Accordingly, ultrasound of the small intestine is an attractive clinical tool to study patients with a range of diseases.

Oral contrast-enhanced sonography for the diagnosis and grading of postsurgical recurrence of Crohn's disease

BACKGROUND

Postsurgical recurrence (PSR) is very common in patients with Crohn's disease (CD) and previous surgery. Endoscopy is crucial for the diagnosis of PSR, also showing high prognostic value. Bowel sonography (BS) with or without oral contrast enhancement (OCBS) is accurate for CD diagnosis but its role in PSR detection and grading is poorly investigated. The aim was to evaluate the diagnostic accuracy of BS and OCBS for PSR compared to the endoscopical Rutgeerts's grading system.

METHODS

We prospectively performed endoscopy, BS, and OCBS in 40 CD patients with previous bowel resection to provide evidence of possible PSR. Endoscopy, BS, and OCBS were executed 1 year after surgery, with PSR diagnosis and grading made in accordance with Rutgeerts. BS and OCBS were considered suggestive for PSR in the presence of bowel wall thickness (BWT) >3 mm. OCBS was performed after ingestion of 750 mL of polyethylene glycol (PEG). Also, a receiver operating characteristic (ROC) curve was constructed in order to define the best cutoff of BWT to discriminate mild from severe PSR (grade 0-2 versus 3-4 of Rutgeerts) for both BS and OCBS.

RESULTS

In all, 22 out of the 40 CD showed an endoscopic evidence of PSR (55%). A severe PSR was present in 14 patients (64%). Sensitivity, specificity, and positive and negative predictive values were 77%, 94%, 93%, and 80% for BS, and 82%, 94%, 93%, and 84% for OCBS. On the ROC curve a BWT >5 mm showed sensitivity, specificity, and positive and negative predictive values of 93%, 96%, 88%, and 97% for the diagnosis of severe PSR at BS, while a BWT >4 mm was the best cutoff differentiating the mild from the severe CD recurrence for OCBS, with a sensitivity, specificity, and positive and negative predictive values of 86%, 96%, 97%, and 79%, respectively.

CONCLUSIONS

Both BS and OCBS show good sensitivity and high specificity for the diagnosis of PSR in CD, with a BWT >5 mm for BS and BWT >4 mm for OCBS strongly indicative of severe endoscopic PSR. Accordingly, these techniques could replace endoscopy for the diagnosis and grading of PSR in many cases.

Non-invasive techniques for assessing postoperative recurrence in Crohn's disease

Postoperative recurrence after ileo-colonic resection is a feature of Crohn's Disease (CD), almost 73% of patients show endoscopic recurrence at 1 year and 90% at 3 years. After surgical resection for CD, symptoms may be related to the surgical resection itself. Moreover, the development of an early severe endoscopic recurrence within 1 year represents a risk factor for early clinical recurrence. On the basis of these observations, the early detection and assessment of asymptomatic endoscopic recurrence may allow a timely and appropriate treatment of CD patients after ileo-colonic resection. At this purpose, conventional colonoscopy with ileoscopy currently represents the gold standard for assessing CD recurrence, graded according to the Rutgeerts' score. Lesions compatible with CD recurrence can be also detected by conventional radiology, including small bowel follow through and enema, both associated with a high radiation exposure. Due to the ineluctable course of CD after resection, and to the need of a proper follow up for assessing CD recurrence, several alternative, non invasive techniques have been searched in order to assess the post-operative recurrence, including: faecal alpha 1-antitrypsin clearance, faecal calprotectin, 99Tc-HMPAO scintigraphy, virtual colonoscopy, ultrasonography and, more recently, wireless capsule endoscopy (WCE) and Small Intestine Contrast Ultrasonography (SICUS). Among these, current evidences suggest that in experienced hands, ultrasound examination by SICUS represents a non-invasive technique useful for assessing recurrence in CD patients under regular follow up after surgery. The same findings are suggested for WCE, although the impact risk related to the recurrence or to the surgical anastomosis itself limits the use of this non-invasive technique for assessing CD recurrence after surgery.

Detection of inflammatory bowel disease: diagnostic performance of cross-sectional imaging modalities

Different cross-sectional imaging techniques can be used as a diagnostic tool for the evaluation of inflammatory bowel disease (IBD). In this report the diagnostic performances of ultrasonography, magnetic resonance imaging and computed tomography in the detection of IBD and the evaluation of known IBD are described, together with a short update on patient preparation and imaging technique of the respective modalities discussed.

Laparoscopic versus open ileo-colonic resection in Crohn's disease: short- and long-term results from a prospective longitudinal study

Possible relations between surgical approaches, frequency, and severity of Crohn's disease recurrence after ileo-colonic resection is unknown. We aimed to assess perioperative outcomes and postsurgical complications of laparoscopic versus standard open surgery and to detect differences between the two groups in endoscopical recurrence and patients' satisfaction. Twenty-eight consecutive patients undergoing elective ileo-colonic resection by either laparoscopic approach (n = 15) or conventional open surgery (n = 13) were prospectively enrolled. No mortality or major intraoperative complications were observed in both groups. Significant differences between groups were the median operating time found shorter in the open group than in the laparoscopic group (p = 0.003), the higher dosage of pain killers needed in the open group (p = 0.05), the passage of flatus and\or stool after surgery found faster in group A (p = 0.004) and the shorter recovery period in the laparoscopic group (p = 0.007). Colonoscopy was performed in 27 patients. The frequency and pattern of recurrence did not differ between the two groups (p = 0.63). Patients' satisfaction was significantly in favor of laparoscopy. Present findings support the feasibility and advantages in the short-term of laparoscopic ileo-colonic resection in patients with Crohn's disease. No differences were observed in terms of frequency, time of onset, and severity of recurrence in a 1-year follow-up.

Laparoscopic versus open ileo-colonic resection in Crohn's disease: short- and long-term results from a prospective longitudinal study

Possible relations between surgical approaches, frequency, and severity of Crohn's disease recurrence after ileo-colonic resection is unknown. We aimed to assess perioperative outcomes and postsurgical complications of laparoscopic versus standard open surgery and to detect differences between the two groups in endoscopical recurrence and patients' satisfaction. Twenty-eight consecutive patients undergoing elective ileo-colonic resection by either laparoscopic approach (n = 15) or conventional open surgery (n = 13) were prospectively enrolled. No mortality or major intraoperative complications were observed in both groups. Significant differences between groups were the median operating time found shorter in the open group than in the laparoscopic group (p = 0.003), the higher dosage of pain killers needed in the open group (p = 0.05), the passage of flatus and\or stool after surgery found faster in group A (p = 0.004) and the shorter recovery period in the laparoscopic group (p = 0.007). Colonoscopy was performed in 27 patients. The frequency and pattern of recurrence did not differ between the two groups (p = 0.63). Patients' satisfaction was significantly in favor of laparoscopy. Present findings support the feasibility and advantages in the short-term of laparoscopic ileo-colonic resection in patients with Crohn's disease. No differences were observed in terms of frequency, time of onset, and severity of recurrence in a 1-year follow-up.

Bowel ultrasound in Crohn's disease: surgical perspective

BACKGROUND

Bowel ultrasound has been proven to be a useful tool in the management of Crohn's disease, particularly in the assessment of intra-abdominal complications, most of which require surgery.

MATERIALS AND METHODS

The National Library of Medicine has been searched for articles on the use of bowel ultrasound in Crohn's disease focusing on aspects of interest to the surgeon.

RESULTS AND CONCLUSIONS

Several studies have demonstrated that bowel ultrasound may be useful to reduce the risk of unnecessary laparotomy in patients presenting acute abdomen with suspected chronic inflammatory bowel disease. Bowel ultrasound has been proven to be of value in the follow-up of Crohn's disease patients since allowing early diagnosis of intra-abdominal complications and, therefore, optimising the diagnostic and surgical approach. At followup, bowel ultrasound may accurately diagnose early postoperative complications and long-term disease recurrence. In patients submitted to conservative surgery, ultrasonography reveals changes in diseased bowel walls that may be predictive of recurrence of the disease, and hence determinant in the choice of medical treatment.

Diagnostics of inflammatory bowel disease

The diagnosis of inflammatory bowel disease (IBD) with its 2 main subforms, Crohn's disease and ulcerative colitis, is based on clinical, endoscopic, radiologic, and histologic criteria. This paradigm remains unchanged despite the advent of new molecular technologies for the examination of serum proteins and genetic sequences, respectively. The main innovations in diagnostic technologies include the development of more sophisticated endoscopic and noninvasive imaging techniques with the aim of improving the identification of complications, in particular malignant diseases associated with IBD. The future will see further progress in the identification of genetic susceptibility factors and of protein biomarkers and their use to describe the molecular epidemiology of IBD. It can be expected that future diagnostic algorithms will include molecular parameters to detect early disease or guide therapies by predicting the individual course of disease.

Ultrasonography of Crohn disease in children

US is increasingly performed in Crohn disease (CD) in children as a first line imaging modality. It reduces the use of other more invasive examinations such as endoscopy, CT or contrast enema. We describe bowel ultrasonography technique, normal bowel appearances on US and pathological patterns in CD. We discuss the current role and limitations of bowel US in CD in children including diagnosis, extent of disease, assessment of disease activity, follow-up and detection of complications. The diagnostic accuracy of US is discussed according to the literature and compared to other imaging modalities. US is currently used for screening in children with the suspicion of inflammatory bowel disease (IBD) with a good negative predictive value. In follow-up, US has a role in monitoring medical treatment by evaluating disease activity, extent of disease and for detecting complications.

Wireless capsule endoscopy and small intestine contrast ultrasonography in recurrence of Crohn's disease

BACKGROUND

The best available tool to assess recurrence of Crohn's disease (CD) is ileocolonoscopy (CC). Small intestine contrast ultrasonography (SICUS) and wireless capsule endoscopy (WCE) are noninvasive techniques able to detect small bowel lesions. In a prospective longitudinal study, we aimed to investigate the usefulness of SICUS and WCE for assessing postoperative recurrence of CD 1 year after surgery, using CC as the gold standard.

METHODS

Twenty-two patients (11 men, median age 33 years, range 22-67 years) undergoing ileocolonic resection for CD were prospectively followed from July 2003 to May 2006, with the Crohn's Disease Activity Index (CDAI) used for clinical assessment every 3 months for 1 year. At 1 year, recurrence was assessed by SICUS and CC, followed by WCE. CD recurrence was assessed by CC (Rutgeerts score). SICUS was performed after ingestion of polyethylene glycol, and WCE was performed with Given M2A equipment.

RESULTS

At 1 year, all 22 patients had inactive CD (CDAI < 150). In 5 patients, WCE was not performed because of luminal narrowing or stenosis. Seventeen of the 22 patients had all 3 techniques performed. CC detected recurrence in 21 of 22 patients. Lesions compatible with recurrence were detected by SICUS in all 22 patients (1 false positive). When considering only the 17 patients studied by all 3 techniques, recurrence was detected by CC in 16 of 17 patients, whereas lesions compatible with recurrence were detected by SICUS in all 17 patients (16 true positives [TPs], 1 FP) and by WCE in 16 of 17 patients (16 TPs, 1 true negative).

CONCLUSIONS

The present findings suggest that SICUS and WCE may be used as noninvasive techniques for the assessment of recurrence of CD in patients being regularly followed up after ileocolonic resection.

Forty-slice MDCT enteroclysis: evaluation after oral administration of isotonic solution in Crohn's disease

OBJECTIVE

The aim of this study was to evaluate the accuracy of multidetector computed tomography (MDCT) enteroclysis after oral hyperhydration with isotonic solution in detecting bowel wall alterations in patients with Crohn's disease.

MATERIALS AND METHODS

Twenty-eight patients with a diagnosis of Crohn's disease established by ileocolonoscopy and histology were enrolled in the study; 15 patients with negative ileocolonoscopy served as controls. In all cases, MDCT enteroclysis was performed after oral administration of 2,000 ml of isotonic solution and intravenous administration of N-butylscopolamine. Axial, isotropic multiplanar and volume-rendered reconstructions were used to evaluate bowel wall thickness, ulceration, contrast enhancement, extraparietal involvement and possible complications.

RESULTS

MDCT enteroclysis identified the typical signs of Crohn's disease in 26 patients (92.8%), with sensitivity of 92.8%, specificity of 100%, positive predictive value 100% and negative predictive value 75%.

CONCLUSIONS

MDCT enteroclysis after oral hyperhydration with isotonic solution showed a high level of accuracy in detecting small bowel changes in patients with Crohn's disease. It can be considered a safe and effective alternative to conventional radiography and small-bowel spiral computed tomography enema, especially in patients who refuse nasojejunal intubation.

The patient with recurrent (sub) obstruction due to Crohn's disease

Stricturing Crohn's disease (CD) occurs in 12-54% of the CD patient population and is associated with significant morbidity and impaired quality of life. The detailed pathophysiology of stricture formation has not been fully elucidated, but is primarily associated with luminal narrowing secondary to inflammation and the fibrosis that ensues during mucosal healing. The diagnosis of stricturing disease is based on clinical signs and symptoms along with imaging modalities. The advantages and shortcomings of each imaging modality are discussed. Treatment options are based on the differentiation between inflammatory versus fibrous-predominant strictures; whereas the former can potentially be managed with conservative medical treatment, the latter necessitates a mechanical solution through endoscopy or surgery. Indications, contra-indications and success rates of the different therapeutic approaches are discussed.

Técnicas seccionales de imagen en la enfermedad de Crohn: ecografía, tomografía computarizada y resonancia magnética

Colonoscopy and Barium contrast studies continue to be the techniques of choice for the evaluation of mucosal lesions in Crohn's disease. However, these techniques have limited capacity for demonstrating the transmural and extramural extension of the disease. Although ultrasound, CT, and MRI cannot detect early lesions, these techniques satisfactorily show parietal and extraparietal changes caused by the disease, thus complementing the information provided in conventional studies. These three techniques enable the evaluation of the pathological segments, the presence of stenosis and dilatation, and extramural disease (fibrofatty proliferation, fistulae, phlegmons, and abscesses). This information is essential for classifying each patient into one of the three subtypes of Crohn's disease (inflammatory, stenotic, or fistulating). These techniques also enable the evaluation of signs that indicate inflammatory activity (hyperemia, wall enhancement, and increased mesenteric vascularization), and this information, together with the subtype, will determine the treatment. Ultrasound, CT, and MRI should be included in the complete evaluation of the patient with Crohn's disease, together with clinical examination, laboratory tests, and conventional imaging studies. We review the role of ultrasound, CT, and MRI in the diagnosis and evaluation of Crohn's disease, describing patient preparation and examination protocols, as well as the findings in these three techniques. We also discuss the advantages and limitations of each of these techniques and their current clinical roles in this context.

Leukocyte scintigraphy compared to intraoperative small bowel enteroscopy and laparotomy findings in Crohn's disease

BACKGROUND

Leukocyte scintigraphy is a noninvasive investigation to assess inflammation. We evaluated the utility of labeled leukocytes to detect small bowel inflammation and disease complications in Crohn's disease and compared it to whole small bowel enteroscopy and laparotomy findings.

METHODS

Scintigraphy with technetium-99m exametazime-labeled leukocytes was prospectively performed in 48 patients with Crohn's disease a few days before laparotomy; 41 also had an intraoperative small bowel enteroscopy. The same procedures were performed in 8 control patients. Independent grading of scans was compared with the results of enteroscopy and with surgical, histopathologic, and clinical data.

RESULTS

In the 8 control patients leukocyte scan, endoscopy, and histopathology were all negative for the small bowel. In patients with Crohn's disease and small bowel inflammation seen at enteroscopy and/or laparotomy (n = 39) the scan was positive in 33. In 8 patients without macroscopic small bowel inflammation, the scan was positive for the small bowel in 3 patients; at histology, 2 of 3 had inflammation. When combining results for patients and controls, the sensitivity of leukocyte scan for macroscopically evident small bowel inflammation was 0.85, specificity 0.81, accuracy 0.84, positive predictive value 0.92, and negative predictive value 0.68. Scintigraphy detected inflammatory lesions not known before laparotomy in 16 of 47 (34%) Crohn's disease patients and showed uptake in 25 of 35 (71%) bowel strictures. It was diagnostic regarding 4 of 8 abscesses and 9 of 15 fistulas. In 6 patients (13%) lesions first demonstrated by leukocyte scintigraphy were treated during the surgery performed.

CONCLUSIONS

Leukocyte scintigraphy reliably detects small bowel inflammation in Crohn's disease. It gives additional information on the presence of inflammatory lesions in a fraction of patients planned for surgery.

Bowel sonography for the diagnosis and grading of postsurgical recurrence of Crohn's disease

BACKGROUND AND AIMS

Postsurgical recurrence (PSR) is common in patients with Crohn's disease (CD) who have undergone surgery. Endoscopy is crucial for the diagnosis of PSR, showing also high prognostic value. Bowel sonography (BS) is accurate for CD diagnosis, but its role in PSR detection and grading has been poorly investigated. The aim of this study was to evaluate the diagnostic accuracy of BS compared to endoscopy in the detection of PSR.

MATERIALS AND METHODS

Between March 2002 and October 2005, to gain evidence of possible PSR, we prospectively performed endoscopy and BS in 45 CD patients who had undergone previous bowel resection. Endoscopy and BS were carried out 1 year after surgery, with diagnosis and grading of PSR made in accordance with Rutgeerts. BS was considered suggestive for PSR in the presence of bowel wall thickness (BWT)>3 mm. Also, an ROC curve was constructed to define the best cutoff value for BWT to differentiate mild from severe PSR (grade 1-2 vs 3-4 of Rutgeerts).

RESULTS

Of the 45 patients with CD, 24 showed endoscopic evidence of PSR (53%). Severe endoscopic PSR was present in 16 patients (66%). Sensitivity, specificity, and positive and negative predictive values of BS were 79%, 95%, 95%, and 80%, respectively, with a sensitivity of 93% for severe PSR. On the ROC curve, a BWT>5 mm showed sensitivity, specificity, and positive and negative predictive values of 94%, 100%, 100%, and 96%, respectively, in differentiating mild from severe PSR, in remarkable agreement with endoscopy (kappa=0.90).

CONCLUSIONS

BS shows good sensitivity and high specificity for the diagnosis of PSR in CD, with a BWT>5 mm being strongly indicative of severe endoscopic PSR. Hence, BS could replace endoscopy for the diagnosis and grading of PSR in patients who comply poorly with the endoscopic examination.

Bowel ultrasound in Crohn's disease

Most published studies have found bowel ultrasound to be a useful tool in the management of Crohn's disease. Indeed, it has been successfully used as the imaging technique of choice in screening patients with clinically suspected Crohn's disease. In these patients, bowel ultrasound, which is well accepted by patients, non-invasive and of low cost, may be the first diagnostic tool employed for young patients and can be used in the preliminary diagnostic work-up prior to further invasive tests. The most important application of bowel ultrasound is, however, in the follow-up of patients already diagnosed with Crohn's disease, in whom it may be useful to assess the site and extent of the lesions and to ensure the early detection of intra-abdominal complications, particularly abscesses and strictures. In this regard, improving the ultrasound assessment of intramural blood flow by means of colour power-Doppler ultrasonography and intravenous contrast agents may help to differentiate fibrotic and inflammatory strictures, and to discriminate inflammatory masses from intra-abdominal abscesses. Despite several attempts to correlate ultrasound findings with clinical and biochemical activity, there are as yet no convincing data on the usefulness of ultrasound in assessing the activity of Crohn's disease. In contrast, preliminary results are in agreement regarding the usefulness of ultrasound in the assessment of postoperative recurrence and in monitoring the outcome of the disease following surgery. In fact, the persistence of a thickened bowel wall or increased high bowel wall thickening at ultrasound following surgery has been identified as an index of early surgical recurrence. How these data may be usefully employed in the management of individuals with Crohn's disease needs to be investigated in further studies.

Sonoenteroclysis: a new technique for the diagnosis of small bowel diseases

BACKGROUND

Radiologic evaluation of small bowel is usually done by barium examination, which involves considerable radiation exposure. A new sonographic method, sonoenteroclysis, is a promising technique for diagnosing small intestinal disorders. In this study the applicability, performance, and diagnostic yield of sonoenteroclysis were assessed and the results of this novel method were compared with those of barium enteroclysis.

METHODS

Forty-five consecutive patients with suspected small bowel disorder were studied. All patients underwent abdominal ultrasound before and after infusion of an isotonic nonabsorbable electrolyte solution containing polyethylene glycol through a nasojejunal tube (modified Billbao Dotter tube), and images at various levels were obtained. Small bowel wall thickness, luminal narrowing, intestinal dilatation, peristalsis, and extraintestinal complications were noted. It was followed by barium enteroclysis and findings were recorded. Findings of sonoenteroclysis were compared with those of barium enteroclysis.

RESULTS

Satisfactory distention of the intestinal lumen was obtained with sequential visualization of jejunoileal loops in 34.4 +/- 18.4 min. Of 45 patients, 10 showed normal small bowel on sonoenteroclysis and barium enteroclysis. These 10 patients served as controls. Sonoenteroclysis displayed normal diameters smaller than 3.0 and 2.0 cm for the jejunum and ileum, respectively. Bowel wall thickness was 1.7 to 3.0 mm and all five layers of bowel wall could be well appreciated. Valvulae conniventes were clearly visualized with a fold thickness between 1.4 and 2.0 mm. The remaining 35 patients showed abnormalities in the form of strictures, matted bowel loops, dilated loops, thickened folds, deformed ileocecal junction, mass lesions, etc., on sonoenteroclysis and barium enteroclysis. In addition, sonoenteroclysis showed thickened bowel wall with loss of stratification. Extraintestinal findings such as enlarged lymph nodes and ascites were also disclosed at the time of sonography. These were diagnosed subsequently as cases of tuberculosis (n = 23), celiac disease (n = 6), adenocarcinoma (n = 2), leiomyoma (n = 2), Immunoproliferative small intestinal disease (n = 1), and segmental enteritis (n = 1).

CONCLUSIONS

The diagnostic accuracy of sonoenteroclysis for detecting small bowel lesions is comparable to that of barium enteroclysis. This new, widely available, inexpensive, and undemanding technique can be used as an initial investigation in the evaluation of patients with small bowel disorders.