Clinical value of technetium-99m-HMPAO-labeled leukocyte scintigraphy and spiral computed tomography in active Crohn's disease

Imaging of Gastrointestinal Tract Ailments

Gastrointestinal (GI) disorders comprise a diverse range of conditions that can significantly reduce the quality of life and can even be life-threatening in serious cases. The development of accurate and rapid detection approaches is of essential importance for early diagnosis and timely management of GI diseases. This review mainly focuses on the imaging of several representative gastrointestinal ailments, such as inflammatory bowel disease, tumors, appendicitis, Meckel's diverticulum, and others. Various imaging modalities commonly used for the gastrointestinal tract, including magnetic resonance imaging (MRI), positron emission tomography (PET) and single photon emission computed tomography (SPECT), and photoacoustic tomography (PAT) and multimodal imaging with mode overlap are summarized. These achievements in single and multimodal imaging provide useful guidance for improved diagnosis, staging, and treatment of the corresponding gastrointestinal diseases. The review evaluates the strengths and weaknesses of different imaging techniques and summarizes the development of imaging techniques used for diagnosing gastrointestinal ailments.

Diagnostic performance of 18F-FDG-PET versus scintigraphy in patients with inflammatory bowel disease: a meta-analysis of prospective literature

OBJECTIVE

The aim of this study was to evaluate the diagnostic performance of fluorine-18 fluorodeoxyglucose-PET (F-FDG-PET), leukocyte scintigraphy (LS), and monoclonal antigranulocyte antibody scintigraphy (MAAS) in patients with inflammatory bowel disease (IBD) and perform pairwise comparisons of the diagnostic accuracy between these different imaging modalities.

METHODS

Through a search of PubMed, EMBASE, and the Cochrane Library (January 1993-May 2013), we performed a random effects meta-analysis and constructed summary receiver operating characteristic curves on per-bowel-segment or per-patient basis. Two-sample Z-tests were performed to evaluate differences in sensitivity, specificity, area under the curve (AUC), and the Q* index between any two diagnostic modalities on per-bowel-segment basis.

RESULTS

Twenty prospective studies were reviewed. On per-bowel-segment basis, the F-FDG-PET had a pooled sensitivity of 0.84, specificity of 0.86, AUC of 0.913, and Q* index of 0.845, whereas for LS, the corresponding values were 0.79, 0.86, 0.877, and 0.808, respectively, and for MAAS they were 0.45, 0.94, 0.524, and 0.518, respectively. On per-patient basis, the corresponding values of LS were 0.91, 0.85, 0.937, and 0.874, respectively. Statistically significant differences were not found in the sensitivity, specificity, AUC, and Q* index between F-FDG-PET and LS on per-bowel-segment basis.

CONCLUSION

F-FDG-PET has a high degree of diagnostic performance compared with LS and MAAS on per-bowel-segment basis in patients with IBD. LS may be used with satisfactory diagnostic accuracy in detecting active IBD when PET systems are unavailable. A larger prospective validation of these findings would be valuable.

Detection of DSS-induced gastrointestinal mucositis in mice by non-invasive optical near-infrared (NIR) imaging of cathepsin activity

Approximately 1.4 million people of the US population suffer from Inflammatory Bowel Disease (IBD) of which the most common conditions are ulcerative colitis (UC) and Crohn disease (CD). Colonoscopy and small bowel follow through are considered the current gold standard in diagnosing IBD. However, improved imaging and increased diagnostic sensitivity could be beneficial. Optical molecular imaging has the potential to become a powerful and practical tool for early detection, image-guided biopsy, and surgery in diagnosing and treating patients with IBD. Here we used a well characterized chemical model to initiate experimental IBD in mice by feeding with dextran sulfate sodium (DSS) containing drinking water in an attempt to investigate the utility of non-invasive infrared (NIR) optical imaging in the detection gastrointestinal (GI) injury. We employed a "smart probe" (ProSense680) cleaved and fluorescently activated in the NIR-spectrum by various forms of secreted cathepsins. This probe has previously been shown to serve as a biomarker for the homing of inflammatory cells to injury. Our investigation suggests that NIR optical imaging can detect cathepsin-dependent probe cleavage non-invasively in animals with DSS-induced IBD. Increased tissue probe-retention and fluorescence was associated with increased infiltration of inflammatory cells, epithelial atrophy and sterilization of the mucosa. Furthermore, using NIR-imaging ex vivo we were able to document regional "hot spots" of inflammatory damage to the large intestine suggesting this method potentially could be coupled with colonoscopy investigation to aid in the sampling and the diagnostics of IBD.

Diagnostic accuracies of MR enterography and CT enterography in symptomatic Crohn's disease

OBJECTIVE

In patients, with symptomatic Crohn's disease (CD), valid information about the presence or absence of small bowel disease activity and stenosis is clinically important. Such information supports decisions about medical or surgical therapy and can be obtained with MR enterography (MRE) or CT enterography (CTE).

MATERIALS AND METHODS

A total of 50 patients with symptomatic pre-existing CD and a demand for small bowel imaging to support changes in treatment strategy were included in this prospective and blinded study. MRE and CTE were performed on the same day in alternating order and subsequently compared with the gold standard: pre-defined lesions at ileoscopy (n = 30) or surgery with (n = 12) or without (n = 3) intra-operative enteroscopy.

RESULTS

A total of 35 patients had active small bowel CD (jejunum 0, ileum 1, (neo)-terminal ileum 34) and 20 had small bowel stenosis. The sensitivity and specificity of MRE for detection of small bowel CD was 74% and 80% compared to 83% and 70% with CTE (p ≥ 0.5). MRE and CTE detected small bowel stenosis with 55% and 70% sensitivities, respectively (p = 0.3) and 92% specificities.

CONCLUSIONS

MRE and CTE have comparable diagnostic accuracies for detection of small bowel CD and stenosis. In symptomatic patients with CD and high disease prevalence, positive predictive values are favorable but negative predictive values are low. Consequently, MRE and CTE can be relied upon, if a positive result is obtained whereas a negative enterography should be interpreted with caution.

The labeled-leukocyte scan in the study of abdominal abscesses

AIM

The purpose of the present paper was to review the literature over the last 30 years to assess the value of radionuclide imaging, particularly labeled leukocyte scan, as compared to other imaging modalities in the management of abdominal abscesses.

METHODS

A systematic review of the published studies in humans cited in PubMed written in English, French, German, Italian, and Spanish was made.

RESULTS

Ultrasound (US) has lower sensitivity than leukocyte scan (LS), particularly in patients without localizing signs, while CT has higher sensitivity than US, but less than LS. On the other hand, CT had higher specificity than both LS and US.

DISCUSSION

LS is the more sensitive method to localize abdominal abscesses and may guide dedicated US and CT investigations to improve their diagnostic potential. Further diagnostic evolution is expected from the routine use of hybrid SPECT/CT systems.

Nuclear imaging of autoimmunity: focus on IBD and RA

There is a need for methods to improve the diagnosis, patient staging and evaluation of therapeutic response in patients with autoimmune conditions to improve patient care. Inflammatory bowel disease (IBD) and rheumatoid arthritis (RA) are two inflammatory diseases characterized by involvement of innate and adaptive immune components that change the metabolic state of their respective target tissues, thus providing an opportunity for molecular imaging probes to detect such changes. Optimally, such probes and the imaging methods employed would be non-invasive, robust and reproducible, give a quantitative result, report on the status of the affected tissue(s) and respond to the effects of a therapeutic molecule. Positron emission tomography (PET) and single photon emission computed tomography (SPECT) are nuclear imaging approaches that have the potential to satisfy such requirements. In this review, the work to date and the potential of PET and SPECT imaging probes in these two inflammatory conditions, IBD and RA, are discussed.

Imaging of inflammation by PET, conventional scintigraphy, and other imaging techniques

Nuclear medicine imaging procedures play an important role in the assessment of inflammatory diseases. With the advent of 3-dimensional anatomic imaging, there has been a tendency to replace traditional planar scintigraphy by CT or MRI. Furthermore, scintigraphic techniques may have to be combined with other imaging modalities to achieve high sensitivity and specificity, and some may require time-consuming labeling procedures. On the other hand, new developments such as combined SPECT/CT increase the diagnostic power of scintigraphy. Also, the advent of PET had a considerable impact on the use of nuclear medicine imaging techniques. In this review, we aim to provide nuclear medicine specialists and clinicians with the relevant information on rational and efficient use of nuclear medicine imaging techniques in the assessment of patients with osteomyelitis, infected vascular prostheses, metastatic infectious disease, rheumatoid arthritis, vasculitis, inflammatory bowel disease, sarcoidosis, and fever of unknown origin.

Imaging of cell trafficking in Crohn's disease

Inflammatory bowel diseases are represented by ulcerative colitis and Crohn's disease, both consisting of a chronic, uncontrolled inflammation of the intestinal mucosa of any part of the gastrointestinal tract with patchy or continuous inflammation. Ileo-colonoscopy is considered the current gold standard imaging technique for the diagnosis. However, as the majority of patients need a long-term follow-up it would be ideal to rely on a non-invasive technique with good compliance. This review focuses on nuclear medicine imaging techniques in Crohn's disease. Different scintigraphic methods of imaging cells involved in the pathogenesis are described. The radiopharmaceuticals can be divided into non-specific radiopharmaceuticals for inflammation and specific radiopharmaceuticals that directly image lymphocytes involved in the process. This non-invasive molecular imaging approach can be useful also because it images the small bowel or other areas--where colonoscopy is not useful-and that it may play a role for constant follow-up, because relapses are frequent. Finally, an update on other imaging modalities, and particularly MRI, in the evaluation of Crohn's disease activity, is provided. Although MRI cannot directly detect inflammatory cells, it has shown a high sensitivity in detecting the macroscopic signs of inflammation at the level of the intestinal wall affected by Crohn's disease and Ulcerative colitis. The current diagnostic value of MRI in the detection of inflamed bowel segment and in the assessment of CD activity, as well the potentials MR spectroscopy, MR diffusion imaging and MR molecular imaging, is briefly discussed.

Role of scintigraphy in inflammatory bowel disease

The diagnosis of inflammatory bowel disease (IBD) depends on direct endoscopic visualization of the colonic and ileal mucosa and the histological study of the obtained samples. Radiological and scintigraphic methods are mainly used as an adjunct to endoscopy. In this review, we focus on the diagnostic potential of nuclear medicine procedures. The value of all radiotracers is described with special reference to those with greater experience and more satisfactory results. Tc-99m hexamethylpropylene amine oxime white blood cells remain a widely acceptable scintigraphic method for the diagnosis of IBD, as well as for the evaluation of disease extension and severity. Recently, pentavalent Tc-99m dimercaptosuccinic acid has been recommended as an accurate variant and a complementary technique to endoscopy for the follow-up and assessment of disease activity. Positron emission tomography alone or with computed tomography using fluorine-18 fluorodeoxyglucose appears to be a promising method of measuring inflammation in IBD patients.

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.

Inflammatory bowel disease diagnosed with US, MR, scintigraphy, and CT: meta-analysis of prospective studies

PURPOSE

To compare, by performing a meta-analysis, the accuracies of ultrasonography (US), magnetic resonance (MR) imaging, scintigraphy, computed tomography (CT), and positron emission tomography (PET) in the diagnosis of inflammatory bowel disease (IBD).

MATERIALS AND METHODS

MEDLINE, EMBASE, CINAHL, and Cochrane databases were searched for studies on the accuracy of US, MR imaging, scintigraphy, CT, and PET, as compared with a predefined reference standard, in the diagnosis of IBD. Sensitivity and specificity estimates were calculated on per-patient and per-bowel-segment bases by using a bivariate random-effects model.

RESULTS

Thirty-three studies, from a search that yielded 1406 articles, were included in the final analysis. Mean sensitivity estimates for the diagnosis of IBD on a per-patient basis were high and not significantly different among the imaging modalities (89.7%, 93.0%, 87.8%, and 84.3% for US, MR imaging, scintigraphy, and CT, respectively). Mean per-patient specificity estimates were 95.6% for US, 92.8% for MR imaging, 84.5% for scintigraphy, and 95.1% for CT; the only significant difference in values was that between scintigraphy and US (P = .009). Mean per-bowel-segment sensitivity estimates were lower: 73.5% for US, 70.4% for MR imaging, 77.3% for scintigraphy, and 67.4% for CT. Mean per-bowel-segment specificity estimates were 92.9% for US, 94.0% for MR imaging, 90.3% for scintigraphy, and 90.2% for CT. CT proved to be significantly less sensitive and specific compared with scintigraphy (P = .006) and MR imaging (P = .037)

CONCLUSION

No significant differences in diagnostic accuracy among the imaging techniques were observed. Because patients with IBD often need frequent reevaluation of disease status, use of a diagnostic modality that does not involve the use of ionizing radiation is preferable.

Imaging of the small bowel in Crohn's disease: A review of old and new techniques

The investigation of small bowel morphology is often mandatory in many patients with Crohn’s disease. Traditional radiological techniques (small bowel enteroclysis and small bowel follow-through) have long been the only suitable methods for this purpose. In recent years, several alternative imaging techniques have been proposed. To review the most recent advances in imaging studies of the small bowel, with particular reference to their possible application in Crohn’s disease, we conducted a complete review of the most important studies in which traditional and newer imaging methods were performed and compared in patients with Crohn’s disease. Several radiological and endoscopic techniques are now available for the study of the small bowel; each of them is characterized by a distinct profile of favourable and unfavourable features. In some cases, they may also be used as complementary rather than alternative techniques. In everyday practice, the choice of the technique to be used stands upon its availability and a careful evaluation of diagnostic accuracy, clinical usefulness, safety and cost. The recent development of innovative imaging techniques has opened a new and exciting area in the exploration of the small bowel in Crohn’s disease patients.

Management of inflammatory bowel diseases in Eastern Europe

Limited data are available on the management of inflammatory bowel diseases (IBD) in East European countries. The diagnostic tools and most treatment options are also available in Eastern Europe. The diagnostic procedures commonly used became more sophisticated in the past few years, with a greater use of computed tomography/magnetic resonance imaging and serology testing; however, double contrast barium enema, enteroclysis, and endoscopy remained standard. The medical therapy and surgical strategies are also somewhat different from those applied in Western countries. In ulcerative colitis, besides mesalazine, the use of sulphasalazine is still frequent, while azathioprine is only used in a minority of patients. The use of conventional corticosteroids is common and the rate of non-colorectal cancer associated colectomies is low. In contrast, 5-aminosalicylates are still used for maintenance in Crohn's disease and azathioprine is generally less frequently given compared with Western Europe. Biological agents have also become available about five years ago, yet their use is restricted mainly to specialised centres.

Nuclear medicine imaging of inflammatory/infective disorders of the abdomen

Different nuclear medicine modalities are currently used to study inflammatory and infective disorders of the abdomen. They are usually complementary to radiology and endoscopy, but they play a pivotal role in particular clinical situations. Several radiopharmaceuticals (e.g., 111In or 99mTc labelled white blood cells, monoclonal antibodies, human polyclonal immunoglobulins, 75Ga citrate) are commercially available, but they can not be used indifferently to study abdominal inflammatory disorders. The lack of comparative studies showing the accuracy of each radiopharmaceutical for the study of inflammatory/infective abdominal diseases does not allow the best nuclear medicine technique(s) to be chosen in an evidence-based manner. To this end we performed a meta-analysis of peer reviewed articles published between 1984 and 2004 describing the use of nuclear medicine imaging for the study of inflammatory bowel disorders, appendicitis and vascular graft infections. A guideline for the optimal radiopharmaceutical(s) to be used in each clinical condition and for different aims is provided.

Clinical significance of granuloma in Crohn’s disease

AIM: Granuloma is considered the hallmark of microscopic diagnosis in Crohn’s disease (CD), but granulomas can be detected in only 21-60% of CD patients. The aim of this study was to evaluate the frequency of granulomas by multiple endoscopic biopsies in patients with CD and to examine whether group of patients with or without granuloma exhibit a different clinical course.

METHODS: Fifty-six patients with newly diagnosed CD were included in the study. Jejunoscopy, enteroclysis and ileo-colonoscopy were performed in all patients. At least two biopsy specimens from each examined gastrointestinal segment were examined microscopically searching granuloma. The clinical course was followed in all patients, and extraintestinal manifestations as well as details of any immunosuppressive therapy and surgical intervention were noted.

RESULTS: Granuloma was found in 44.6% of the cases (25 patients). Patients with granuloma had higher activity parameters at the time of the biopsies. Extraintestinal manifestations were observed and surgical interventions were performed more often in the granuloma group. The need of immunosuppressive therapy was significantly more frequent in the patients with granuloma. Granuloma formation is more often seen in younger patients, and mainly in the severe, active penetrating disease.

CONCLUSION: The significantly higher frequency of surgical interventions and immunosuppressive therapy suggests that granuloma formation is associated with a more severe disease course during the first years of CD.

Clinical relevance of transabdominal ultrasonography and magnetic resonance imaging in patients with inflammatory bowel disease of the terminal ileum and large bowel

BACKGROUND

Ileocolonoscopy represents the diagnostic standard in the work-up of patients with inflammatory bowel diseases (IBD). Patients are often reluctant to be colonoscoped because of the invasiveness and pain sensation during colonoscopy.

AIMS

To compare the usefulness oftransabdominal ultrasound (US) and magnetic resonance imaging (MRI) in assessing disease extension and activity in patients with IBD restricted to the terminal ileum and large bowel.

PATIENTS AND METHODS

61 patients with IBD [37 Crohn's disease (CD) and 24 ulcerative colitis (UC)] were prospectively studied. All patients underwent clinical and laboratory assessment, ileocolonoscopy, transabdominal sonography, and MRI within 5 days. Involved bowel segments were defined as those with bowel wall thickness >3 mm and increased Doppler signal on US or contrast enhancement of the bowel wall on MRI. To compare disease activity endoscopic, MRI and US findings were graded with newly developed scores.

RESULTS

The segment-by-segment analysis revealed an overall accuracy of 89% for US and 73% for MRI in identifying active IBD. The accuracy was better in patients with UC than in patients with CD for both US and MRI. The endoscopic activity index (EAI) correlated stronger with the US activity index (r = 0.884) than with the MRI activity index (r = 0.344). The correlation of US and MRI activity indices with EAI was better in patients with UC compared with patients with CD. All three imaging methods showed a significant correlation with clinical disease activity in patients with UC but not in patients with CD.

CONCLUSION

This study provides strong evidence that US should be considered as a first-choice method for follow-up of patients with IBD of the terminal ileum and large bowel.

Modern imaging using computer tomography and magnetic resonance imaging for inflammatory bowel disease (IBD) AU1

Radiologic imaging--especially of the small bowel--plays an important role in the diagnosis and management of patients with inflammatory bowel disease. The radiographic examination of the small intestine with barium either as enteroclysis or as small bowel follow through are still the mainstays in small bowel imaging. However, abdominal CT or MRI, which has the advantage of not utilizing ionizing radiation, or the techniques of CT- or MR-enteroclysis, are overall comparable with regard to the sensitivity and specificity in detecting intestinal pathologies and have already replaced the conventional techniques in centers dedicated to the management of inflammatory bowel disease. Additionally, these cross-sectional imaging techniques provide, in a sense, a "one stop abdominal imaging workup," the diagnosis of extraluminal disease manifestations or complications. Future developments of CT- or MR-based virtual colonography and endoscopy in patients with inflammatory bowel disease are currently being investigated, but should momentarily be considered as purely experimental approaches.

Use of nuclear scintigraphy with 99m Tc- HMPAO-labelled leucocytes to assess small intestinal malabsorption in 17 horses

The diagnostic and prognostic value of nuclear scintigraphy with technetium-99m-labelled hexamethyl-propyleneamine oxime-labelled leucocytes was assessed in 17 horses with weight loss due to gastrointestinal malabsorption by comparing the results with the results obtained from 13 normal control horses. Intestinal uptake of activity was detected in 12 of the 17 cases but none of the control horses. The technique was therefore specific for intestinal pathology, but failed to detect some horses that might have had intestinal pathology. No indications of the horses' specific pathology were obtained, and their prognosis or response to treatment could not be predicted.

Active inflammatory bowel disease: evaluation with 99mTc (V) DMSA scintigraphy

PURPOSE

To evaluate the use of pentavalent (V) technetium 99m (99mTc) dimercaptosuccinic acid (DMSA) scintigraphy for the assessment of disease activity in patients with inflammatory bowel disease (IBD).

MATERIALS AND METHODS

99mTc (V) DMSA scintigraphy was performed in 76 patients. There were 36 patients with active IBD (11 with ulcerative colitis, 25 with Crohn disease), 28 patients with inactive disease (eight with ulcerative colitis, 20 with Crohn disease), and 12 patients with miscellaneous bowel disease. Sensitivity and specificity of 99mTc (V) DMSA scintigraphy in the diagnosis of IBD were calculated. In the group with active IBD, the disease activity and laboratory indices, as well as the endoscopic and histologic activity, were compared with the scanning activity index. Correlation coefficients between them were calculated with the Spearman rank test.

RESULTS

99mTc (V) DMSA scintigraphy had a 92% (33 of 36) sensitivity and an 86% (24 of 28) specificity in the detection of active IBD. A significant correlation between disease activity indices and scintigraphy score was demonstrated. Endoscopic and histologic activity was significantly correlated (P =.005 and.02, respectively, overall disease activity) with the scanning activity score. Of the group of patients with miscellaneous bowel disease, three with ischemic colitis had negative findings at scintigraphy.

CONCLUSION

99mTc (V) DMSA scintigraphy provides a noninvasive, practical, and accurate assessment of IBD activity.

Bowel wall thickening in patients with Crohn's disease: CT patterns and correlation with inflammatory activity

AIM

To assess CT patterns of bowel wall thickening in patients with Crohn's disease and to correlate these patterns with inflammatory activity.

MATERIALS AND METHODS

We conducted a retrospective review of 58 helical abdominal CT scans of 53 patients with pathologically proven Crohn's disease. CT patterns of thickened bowel wall were divided into four types based on patterns of mural stratification and enhancement: type A, multilayered mural stratification; type B, two layers with strong mucosal enhancement and prominent low-density submucosa; type C, two layers without strong mucosal enhancement; and type D, homogeneous enhancement. We evaluated CT findings of the bowel and adjacent structures. We also reviewed pathologic features and clinical data to determine inflammatory activity.

RESULTS

Fifty-five (95%) of 58 CT examinations showed bowel wall thickening. Of these 55 CT scans, type A pattern was found in 33 (60%), type B in 10 (18%), type C in five (9%), and type D in seven (13%). CT scans with type A showed significantly more wall thickening than those with either type C or type D. Histology revealed 43 cases with active disease and 12 with quiescent appearance. Thirty of 33 CT scans with type A and all 10 with type B were classified as acute disease, and three of five with type C and six of seven with type D as quiescent.

CONCLUSION

In patients with Crohn's disease, CT patterns of bowel wall thickening correlated with inflammatory activity. Thickened bowel wall with layering enhancement is predictive of acute disease, and that of homogeneous enhancement suggests quiescence.

Enteroclysis and computed tomography enteroclysis

Enteroclysis, the most detailed radiologic examination of the small bowel, can be a challenge for both patient and radiologist. This article broadly outlines the principal technical features of the standard enteroclysis procedure and discusses its diagnostic advantages and indications, as well as its limitations and difficulties. A comparative assessment of computed tomography-enteroclysis and the emerging magnetic resonance adaptation complements the survey of current approaches to radiologic small bowel diagnostics.

Diagnostic methodologies: serology, endoscopy, and radiology

The two major inflammatory bowel diseases, Crohn's disease (CD) and ulcerative colitis (UC), represent clinicopathologic entities that traditionally have been diagnosed on the basis of a combination of clinical, radiologic, endoscopic, and histologic features. Serum perinuclear antineutrophil cytoplasmic antibodies (pANCA) and anti-Saccharomyces cerevisiae antibodies (ASCA) have recently been added to our diagnostic armamentarium. Several studies have demonstrated that UC-associated pANCAs recognize nuclear antigens. Additional studies have demonstrated that the pANCA human monoclonal antibody (mAb) Fab 5-3 reacts with histone H1 and with bacterial and mycobacterial antigens. Several reports have suggested that, in CD, pANCA and ASCA are correlated with colonic and small bowel disease respectively. One study found that higher ASCA levels were correlated with more aggressive CD. Serology may prove to be useful in predicting the evolution of indeterminate colitis. Magnetic resonance imaging (MRI) and leukocyte scintigraphy hold promise in identifying inflammatory CD. MRI enteroclysis is useful in identifying both luminal small bowel disease and extraluminal complications. A recent study of surveillance colonoscopy in extensive Crohn's colitis showed a high risk of dysplasia and cancer.