Diagnostic imaging in Crohn's disease: what is the new gold standard?

Role of Endoscopic Ultrasound in the Diagnosis and Management of Complications of Inflammatory Bowel Disease

Inflammatory bowel disease-related complications are associated with a decreased quality of life, requirement for surgery, and increased morbidity. Endoscopic ultrasound (EUS) is accurate at identifying and characterizing perianal fistulae and abscesses and helps guide treatment decisions. EUS also allows us to accurately assess for mucosal and transmural inflammation and thus can help differentiate Crohn's disease from ulcerative colitis (UC). EUS use can help predict dysplasia in UC, and monitoring transmural inflammation can help assess response to treatment. In addition to diagnostic EUS, therapeutic EUS techniques have been used to endoscopically drain abscesses and bypass strictures in Crohn's disease.

Comparing the Diagnostic Value of FDG PET or PET/CT With FDG PET/MR in Inflammatory Bowel Disease-A Systematic Review and Meta-analysis

BACKGROUND

The aim of this study was to compare the diagnostic value of 18 F-FDG PET or PET/CT with FDG PET/MR in patients with inflammatory bowel disease (IBD).

METHODS

A comprehensive search was performed in PubMed for studies reporting the diagnostic performance of FDG PET (PET/CT) and FDG PET/MR in IBD from the inception of the database to March 14, 2024, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Fourteen studies were included in this systematic review and meta-analysis. Pooled estimates of segment-based sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio for FDG PET (PET/CT) and FDG PET/MR were calculated alongside 95% confidence intervals. Summary receiver operating characteristic (SROC) curves were plotted, and the area under the SROC curve was determined alongside the Q * index.

RESULTS

The segment-based pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and area under the SROC curve of FDG PET (PET/CT) for diagnosing IBD (9 studies) were 0.81, 0.86, 5.76, 0.22, 31.92, and 0.92, respectively. Those of FDG PET/MR (5 studies) were 0.78, 0.92, 10.97, 0.25, 51.79, and 0.95. There was no significant difference in the abilities of detecting or excluding IBD between FDG PET (PET/CT) and FDG PET/MR.

CONCLUSIONS

For diagnostic value in patients with IBD, there was no significant difference between FDG PET (PET/CT) and FDG PET/MR. Both FDG PET (PET/CT) and FDG PET/MR have demonstrated high diagnostic performance for accurate diagnosing in patients with IBD.

Quantitative analysis of contrast-enhanced ultrasound and superb microvascular imaging for the evaluation of disease activity in inflammatory bowel disease

OBJECTIVE

To evaluate the effectiveness of conventional US (ultrasound), SMI (superb microvascular imaging), and CEUS (contrast-enhanced ultrasound) features for the assessment of the activity of inflammatory bowel disease.

METHODS

Conventional US, CEUS and SMI features of 76 patients were retrospectively analyzed. Patients were categorized into two groups: active group (n = 57) and inactive group (n = 19), with endoscopic results as reference standard. Results in the active group and inactive group were compared using an independent t-test, Mann-Whitney U test, chi-square test, and receiver operating characteristic curve (ROC) analysis. Cut-off values were determined using ROC analysis, and sensitivity and specificity were calculated. US quantitative and TIC-based quantitative parameters were analyzed, and each patient was scored based on the parameters that are statistically significant and immediately available in the clinic to evaluate the diagnostic ability of conventional US, SMI, and CEUS features for active IBD patients.

RESULTS

Qualitative parameters such as CEUS enhancement pattern I/II, LimbergIII/IV, and lost bowel stratification were reliable indicators of active patients. Quantitative parameters such as bowel thickness and VI of mSMI were reliable indicators of active patients. Patients scored based on these statistically significant parameters with a score ≥3, were highly suspected to be active patients. For TIC-based quantitative parameters, PE, WiAUC, WoAUC, WiWoAUC, WiR, WiPI, and WoR were statistically significant in the differentiation of active IBD from inactive IBD.

CONCLUSIONS

Conventional US, SMI, and CEUS features may help in the differentiation of active IBD from inactive IBD and have potential application value in the choice of treatment options.

Assessment of Ileal Crohn's Disease Activity by Gastrointestinal Ultrasound and MR Enterography: A Pilot Study

INTRODUCTION

In some cases, there may be a discrepancy between the symptomatology alleged by Crohn's disease (CD) patients and the results of laboratory tests or imaging investigations. Ileocolonoscopy with biopsy is the primary investigation for diagnosing and monitoring CD patients. Cross-sectional imaging techniques such as CT or MR enterography (MRE) and intestinal ultrasonography (IUS) have been proposed as complementary methods to colonoscopy for a complete evaluation of this category of patients. This study aims to identify the role of IUS, contrast-enhanced ultrasound (CEUS) and MRE in evaluating ileal CD activity, using clinical severity scores (Crohn's disease activity index-CDAI, Harvey-Bradshaw index-HBI) and faecal calprotectin or C-reactive protein (CRP) levels as reference methods.

MATERIALS AND METHODS

A total of 44 adult patients with ileal CD confirmed using an ileocolonoscopy with biopsy and histopathological examination were assessed by IUS, CEUS and MRE. The evaluation of the disease activity based on the results obtained from the cross-sectional imaging tests was carried out by using some severity scores available in the literature. The sensitivity and specificity of IUS + CEUS and MRE for differentiating active from inactive forms of CD were determined using CDAI, HBI, faecal calprotectin and CRP as reference methods. The accuracy of the results was assessed by the receiver operating characteristics method. The Pearson correlation coefficient was used to determine the types of correlation. A p-value less than 0.05 suggested a statistically significant relationship.

RESULTS

Compared to CDAI, the best correlation was identified for Limberg score (r = 0.667, 95% confidence interval (CI) [0.46, 0.8], p < 0.001), followed by MaRIAs score (r = 0.614, 95% CI [0.39, 0.77], p < 0.001). A sensitivity of 93.33% and a specificity of 71.43% (AUC = 0.98) were demonstrated in the case of Limberg score for differentiating patients with active disease from those in remission and for MaRIAs score a sensitivity of 100.00% and a specificity of 57.14% (AUC = 0.97). Regarding HBI, the best correlation was observed for MaRIAs score (r = 0.594, 95% CI [0.36, 0.76], p < 0.001). Also, faecal calprotectin showed the best correlation with MaRIAs score (r = 0.697, 95% CI [0.46, 0.84], p < 0.001), but in the case of CRP, there was only a weak correlation for all evaluated scores.

CONCLUSIONS

Although magnetic resonance imaging does not appear to be superior to ultrasonography in terms of accuracy for differentiating active forms of CD from those in remission, the results of our study suggest that MRE associates a better correlation with clinical severity scores and faecal calprotectin levels compared to ultrasonography. More studies are needed to validate these results.

Magnetic Resonance Enterography Reinvented: Exploring the Potential of a New Natural Beverage as an Alternative to Polyethylene Glycol Solution

The aim of the present study was to test a new oral contrast medium composed of natural components for the magnetic resonance (MR) imaging of small bowel diseases. Between January 2018 and June 2019, 35 patients affected by ileocolic Crohn’s disease (CD) were enrolled in the present study. Each patient underwent two sequential MR enterographies, first with the standard polyethylene glycol (PEG) water solution and, after 3 weeks, with the new natural beverage designed by our team. At the end of the administration of each oral contrast, a satisfaction survey was given to the patients to assess the palatability of both beverages. The intestinal distention and the quality of images were evaluated by two expert radiologists for both studies and the interreader agreement was calculated. According to the satisfaction questionnaire, 97.1% of patients expressed positive judgments regarding the natural beverage (71.4% very good and 25.7% good) whereas only 8.6% of them appreciated the PEG water solution (8.6% good) (p = 0.0001). The degree of intestinal distention was excellent and good in 97.1% of patients after the administration of PEG and in 94.3% of the patients after the administration of the natural beverage, without significant differences between the two products and with almost perfect (k = 0.821) and substantial (k = 0.754) inter-observer variability, respectively. No statistical differences were observed between the two expert radiologists regarding the evaluation of the imaging quality; in particular, they were considered good and excellent in 100% of patients after the administration of PEG water solution and in 97.2% of those who took the natural beverage, with substantial (k = 0.618) and almost perfect (k = 0.858) inter-observer variability, respectively. The new natural beverage demonstrated the same intestinal distension and excellent image quality compared to the synthetic standard oral contrast administered during MRE for small bowel diseases, proving to be a valid alternative with better palatability.

Aptamer-Functionalized Microbubbles Targeted to P-selectin for Ultrasound Molecular Imaging of Murine Bowel Inflammation

PURPOSE

Our objectives were to develop a targeted microbubble with an anti-P-selectin aptamer and assess its ability to detect bowel inflammation in two murine models of acute colitis.

PROCEDURES

Lipid-shelled microbubbles were prepared using mechanical agitation. A rapid copper-free click chemistry approach (azide-DBCO) was used to conjugate the fluorescent anti-P-selectin aptamer (Fluor-P-Ap) to the microbubble surface. Bowel inflammation was chemically induced using 2,4,6-trinitrobenzenesulfonic acid (TNBS) in both Balb/C and interleukin-10-deficient (IL-10 KO) mice. Mouse bowels were imaged using non-linear contrast mode following an i.v. bolus of 1 × 10⁸ microbubbles. Each mouse received a bolus of aptamer-functionalized and non-targeted microbubbles. Mouse phenotypes and the presence of P-selectin were validated using histology and immunostaining, respectively.

RESULTS

Microbubble labelling of Fluor-P-Ap was complete after 20 min at 37 ̊C. We estimate approximately 300,000 Fluor-P-Ap per microbubble and confirmed fluorescence using confocal microscopy. There was a significant increase in ultrasound molecular imaging signal from both Balb/C (p = 0.003) and IL-10 KO (p = 0.02) mice with inflamed bowels using aptamer-functionalized microbubbles in comparison to non-targeted microbubbles. There was no signal in healthy mice (p = 0.4051) using either microbubble.

CONCLUSIONS

We constructed an aptamer-functionalized microbubble specific for P-selectin using a clinically relevant azide-DBCO click reaction, which could detect bowel inflammation in vivo. Aptamers have potential as a next generation targeting agent for developing cost-efficient and clinically translatable targeted microbubbles.

The Use of Endoscopic Ultrasonography in Inflammatory Bowel Disease: A Review of the Literature

The diagnosis of inflammatory bowel disease (IBD) can sometimes be challenging. By corroborating clinical, imaging and histological data, the two main entities of IBD, ulcerative colitis and Crohn's disease (CD), can be differentiated in most cases. However, there remains 10-20% of patients where the diagnosis cannot be accurately established, in which case the term "IBD unclassified" is used. The imaging techniques most used to evaluate patients with IBD include colonoscopy, ultrasonography and magnetic resonance imaging. Endoscopic ultrasonography is mainly recommended for the evaluation of perianal CD. Through this work, we aim to identify other uses of this method in the case of patients with IBD.

Idiopathic myointimal hyperplasia of mesenteric veins depicted by barium enema examination, and conventional and magnifying colonoscopy

A 71-year-old man was admitted to our institution complaining of abdominal pain and constipation. Barium enema examination revealed narrowing, cobble stoning, and longitudinal ulcerations in the sigmoid colon and upper rectum. Conventional colonoscopy, magnifying narrow-band imaging endoscopy, and magnifying chromoendoscopy revealed edematous mucosa, longitudinal ulcerations with luminal narrowing, and multiple pseudopolyps. The histologic examination of the biopsy specimens showed thick-walled (arterialized) capillaries and subendothelial fibrin deposits in the mucosa and submucosa. Based on a preoperative diagnosis of idiopathic myointimal hyperplasia of mesenteric veins (IMHMV), he underwent a laparoscopic resection of the sigmoid colon and upper rectum. The histologic examination of the resected specimens showed marked proliferation of venous walls with marked myointimal thickening and luminal occlusion from the submucosa to the mesentery throughout the entire resected tissue section. The final diagnosis was IMHMV.

Crohn's Disease Activity Evaluation by Transabdominal Ultrasonography: Correlation with Double-Balloon Endoscopy

OBJECTIVES

Transabdominal ultrasonography (US) has been reported as a useful tool for evaluating Crohn's disease (CD) activity. Endoscopic findings and Crohn's disease activity index (CDAI) are currently considered the gold standard for assessing CD activity. We assessed the correlation between US and double-balloon endoscopy (DBE), and CDAI for evaluating CD activity.

METHODS

We analyzed patients with CD undergoing US and DBE within 10 days between the procedures. The intestine was divided into four segments and analyzed by the US scoring system (US-CD) and the simple endoscopic score for Crohn's disease (SES-CD). CDAI was compared with US-CD and SES-CD. Spearman's rank correlation coefficient was used for statistical analysis.

RESULTS

Twenty-five patients with CD (11 women, 14 men; mean age 35.4 ± 14.9 years, range 16-65 years) were enrolled. Twenty-four patients received antitumor necrosis factor inhibitor therapy. CDAI was 128.1 (range 36-227). A significant moderate correlation was found between the US-CD and SES-CD in all segments (ρ = .64, P < .01). The US-CD showed a strong correlation with CDAI (ρ = .78, P < .01), whereas the SES-CD showed a moderate correlation (ρ = .55, P < .05).

CONCLUSIONS

US-CD and SES-CD showed a moderate correlation for assessing CD activity. US-CD showed a stronger correlation with CDAI than SES-CD, suggesting that US could more accurately evaluate the disease activity.

COMPARATIVE ANALYSIS OF TWO ORAL CONTRAST AGENT VOLUMES FOR COMPUTED TOMOGRAPHY ENTEROGRAPHY IN CROHN'S DISEASE PATIENTS

BACKGROUND

Crohn's disease (CD) is an inflammatory bowel disease characterized by a chronic and recurrent inflammation of the gastrointestinal tract caused by an interaction of genetic and environmental factors.

OBJECTIVE

To compare the quality and acceptance of two different oral contrast volumes for computed tomography enterography in Crohn's disease patients.

METHODS

A cross-sectional study was conducted in 58 consecutive Crohn's disease patients who randomly received an oral contrast agent composed of 78.75 g polyethylene glycol diluted in either 1,000 mL or 2,000 mL of water. An examination was performed to evaluate the presence of inflammation or complications in the small bowel. The variables included the quality of intestinal segment filling and luminal distension, and oral contrast agent acceptance and tolerance in the patients. Statistical analysis included descriptive statistics and association tests.

RESULTS

A total of 58 patients were assessed, in which 58.6% were female, 34.5% exhibited clinically-active disease, and 63.8% were receiving biologic therapy. As for comparative analysis between the two different volumes of oral contrast, no statistically significant difference was found regarding bowel loop filling (P=0.58) and adequate luminal distension (P=0.45). Patients who received a larger volume (2,000 mL) exhibited side-effects more frequently (51.7% vs 31.0%; P=0.06) and had greater difficulty ingesting the agent (65.5% vs 37.9%; P=0.07) compared with a volume of 1,000 mL.

CONCLUSION

The quality of computed tomography enterography was not influenced by the contrast volume. However, acceptance and tolerance were better in the 1,000 mL group.

Utilization of Diagnostic Imaging and Ionizing Radiation Exposure-Has the Tide Already Turned?

Inflammatory bowel diseases require repetitive abdominal imaging for diagnosis, follow-up, or management of complications. This editorial comments on the large incident-based case-control study on utilization of diagnostic imaging and ionizing radiation exposure by Nguyen and colleagues published in this issue.

Crohn’s disease with isolated gastric involvement as an example of a rare disease phenotype: a clinical case

Crohn's disease (CD), along with ulcerative colitis, is one of the predominant nosological forms of inflammatory bowel diseases. In CD, any part of the gastrointestinal tract can be affected; however, the process is commonly associated with terminal ileum or colon involvement. CD cases with isolated or mixed involvement of upper gastrointestinal tract (esophagus, stomach, and duodenum) are rare and least studied types of the disease. In isolated stomach involvement, the complaints are non-specific and include epigastric pain, gastric dyspepsia, early satiety, decreased appetite, and nausea. Isolated CD of upper gastrointestinal tract can be diagnosed after comprehensive work-up and always requires a high diagnostic level, including clinical, endoscopic and morphological one. We present a clinical case of CD with isolated stomach involvement in a 62-year-old woman. The diagnosis was confirmed by the histopathological findings of an epithelioid cell granuloma in the gastric antrum. Treatment with systemic corticosteroids reduced the disease clinical activity and improved the histological characteristics of the gastric biopsy sampled obtained by endoscopy. In this clinical case, there were specific macroscopic gastric lesions found at endoscopy in CD patients with upper gastrointestinal tract involvement, which is characterized by thickened longitudinal folding and linear grooves. This type of lesion has been described in the literature as “bamboo joint-like appearance”.

Conclusion: Comprehensive assessment of clinical manifestations, endoscopic and histopathological specific features is crucial for the timely diagnosis and treatment of inflammatory bowel diseases.

In vivo evaluation of targeted delivery of biological agents using barium sulfate

This study was aimed to monitor the transit through the intestine by X-ray imaging using barium sulfate (BS) as tracer. The in vitro features of monolithic tablets were correlated with their in vivo behavior in order to provide a tool for the development of targeted formulations containing macromolecular bioactive agents. The impact of BS on various matrices (neutral, ionic) was studied in simulated fluids using the disintegration time (DT) as main parameter. Dry tablets were characterized by spectroscopic methods (X-ray diffraction and Infra-Red) and scanning electron microscopy (SEM). The selected formulations were followed in a beagle dog model. The in vivo and in vitro DT of tablets formulated with BS were compared. Results: anionic excipients carboxymethylcellulose (CMC) and carboxymethylstarch (CMS) protected the active ingredient from the gastric acidity, ensuring its targeted delivery in the intestine. The SEM analysis, before and after transit in simulated fluids, showed that BS remained in the tablets allowing their good follow-up in vivo. The incorporation of 30% protein in tablets with 40% BS had no impact on their behavior. In conclusion, BS and X-ray imagery could be a good alternative to scintigraphy for development of targeted formulations containing high molecular weight bioactive agents.

Upper Gastrointestinal Crohn's Disease: Literature Review and Case Presentation

Upper gastrointestinal tract predominant Crohn's Disease (CD) remains an elusive clinical entity, manifesting limited or vague symptomatology, eluding clinical suspicion, and delaying subsequent diagnostic evaluation. As a result, it has not been widely described and there is a lack of clear recommendations for diagnosis or management. Standard IBD evaluation including serologic testing, imaging, and endoscopy may initially not be fruitful. Furthermore, endoscopic evaluation may be grossly normal in patients without long standing-disease. We describe an 18-year-old male who presented with only unexplained, persistent iron-deficiency anemia. Extensive outpatient testing including multiple endoscopic evaluations with standard biopsies was unfruitful. Ultimately, a positive fecal calprotectin prompted enteroscopy with endoscopic mucosal resection (EMR) in an effort to obtain a larger, deeper tissue specimen. Grossly cobblestoned mucosa along with histopathology revealing focal crypt abscesses, chronic inflammation in the lamina propria, and superficial foveolar epithelial regenerative changes were consistent with CD. This patient's case illustrates the need for a high degree of suspicion for CD in patients with unexplained or persistent iron deficiency anemias. Persistent investigation yielded an elevation in fecal calprotectin suggesting underlying gastrointestinal inflammation and prompted advanced endoscopic evaluation with EMR. Waxing and waning tissue findings are characteristic of CD and pose a unique challenge in patients with upper gastrointestinal predominant pathology. As such, diligent workup including laboratory evaluation, imaging, and serial endoscopy is critical to establish pathology and dictate subsequent management in IBD, especially upper gastrointestinal tract predominant CD.

Crohn's disease in a developing African mission hospital: a case report

Background

A case is reported of innocuous intestinal obstruction requiring surgical intervention that was confirmed to be Crohn’s disease histopathologically in a resource-constrained rural mission hospital in Cameroon.

Case presentation

A 70-year man of Kumbo origin from Northwest region of Cameroon with a history of crampy right lower-quadrant abdominal pain, non-bloody, non-mucoid diarrhea alternating with constipation presented to my institution. Abdominal examination of the patient revealed an ill-defined mass in the right iliac fossa and visible peristalsis. An abdominal computed tomographic scan and barium enema study confirmed a complex ascending colonic and cecal tumor. The patient underwent exploratory laparotomy. The intraoperative finding was a huge complex inflammatory mass involving the cecum, terminal ileum, and sigmoid colon. He subsequently had sigmoidectomy with end–to-end sigmoidorectal anastomosis and a cecal resection, and the proximal ascending colon was exteriorized because end mucoid fistula and terminal ileostomy were performed. The histopathological diagnosis confirmed Crohn’s disease. The patient subsequently received five courses of adjuvant chemotherapy consisting of azathioprine, methotrexate, mesalamine, and methylprednisolone. He had complete disease remission and subsequently had closure of ileostomy with satisfactory postoperative status. The most recent follow-up abdominal computed tomographic scan and colonoscopy revealed disease-free status. The patient is also currently receiving a maintenance dose of rectal mesalamine and oral omeprazole treatment. He has been followed every 2 months in the surgical outpatient clinic over the last 16 months with satisfactory clinical outcome.

Conclusions

Crohn’s disease is uncommon in Africa, and this entity is encountered sparingly. The signs and symptoms of Crohn’s disease overlap with many other abdominal disorders, such as tuberculosis, ulcerative colitis, irritable bowel syndrome, and others. Several publications in the literature describe that it is difficult to make an accurate diagnosis of this disease, despite the fact that many diagnostic armamentaria are available to suggest its presence. Most of the patients with Crohn’s disease are treated conservatively, and a few may require surgical intervention, especially those presenting with complications such as intestinal obstruction, perforations, and abscess as well as fistula formations, as seen in this index patient. Crohn’s disease is considered by many to be a very rare disease in Africa. It is interesting to know that Crohn’s disease, which affects mainly young adults, may debut at any age. The rarity and clinical curiosity of this entity suggested reporting of my patient’s case. Evidence-based up-to-date information on Crohn’s disease is also documented.

Ingestible Contrast Agents for Gastrointestinal Imaging

Gastrointestinal (GI) ailments cover a wide variety of diseases involving the esophagus, stomach, small intestine, large intestine, and rectum. They bring about many inconveniences in daily life in chronic diseases and can even be life threatening in acute cases. Rapid and safe detection approaches are essential for early diagnosis and timely management. Contrast agents for GI imaging can enhance contrast to distinguish abnormal lesions from normal structures. Computed tomography and magnetic resonance imaging are two important diagnostic tools for the evaluation of GI conditions. This review mainly involves several common GI diseases, including inflammatory diseases, intestinal tumors, diarrhea, constipation, and gastroesophageal reflux diseases. Selected contrast agents, such as barium sulfate, iodine-based agents, gadolinium-based agents, and others, are summarized. Going forward, continued endeavors are being made to develop more emerging contrast agents for other imaging modalities.

Ultrasound examination with contrast in the diagnosis of inflammatory bowel disease. The results of the pilot study

Aim. Assessment of diagnostic significance of informativeness and security of ultrasonography with contrast enhancement drug SonoVue in the diagnosis of Crohn's disease (CD) and ulcerative colitis (UC). Materials and methods. The pilot conducted a prospective study which involved 15 patients with inflammatory bowel disease (IBD). All patients gave written consent to participate in the study and processing of personal data. The study included adult patients with an established diagnosis of UC and CD, with proven clinical activity of the disease. Activity was evaluated based on clinical and laboratory data on the scale of best (CDAI >150) for patients with CD and on a scale of Trulove-Witts (2-3 stage) and the Mayo index (DAI) for patients with UC. All the patients underwent colonoscopy with biopsy, ultrasound examination of abdominal cavity organs with the study of the vascularization of the intestinal wall (color Doppler, power Doppler, contrast study). Results. The use of contrast showed additional features in the instrumental evaluation of activity of inflammatory process, identification of complications and assessment of prognosis. Conclusion. The results of ultrasound of the bowel with contrast can be used to assess the activity and stage of disease in patients with UC or CD.

Crohn Disease: Epidemiology, Diagnosis, and Management

Crohn disease is a chronic idiopathic inflammatory bowel disease condition characterized by skip lesions and transmural inflammation that can affect the entire gastrointestinal tract from the mouth to the anus. For this review article, we performed a review of articles in PubMed through February 1, 2017, by using the following Medical Subject Heading terms: crohns disease, crohn's disease, crohn disease, inflammatory bowel disease, and inflammatory bowel diseases. Presenting symptoms are often variable and may include diarrhea, abdominal pain, weight loss, nausea, vomiting, and in certain cases fevers or chills. There are 3 main disease phenotypes: inflammatory, structuring, and penetrating. In addition to the underlying disease phenotype, up to a third of patients will develop perianal involvement of their disease. In addition, in some cases, extraintestinal manifestations may develop. The diagnosis is typically made with endoscopic and/or radiologic findings. Disease management is usually with pharmacologic therapy, which is determined on the basis of disease severity and underlying disease phenotype. Although the goal of management is to control the inflammation and induce a clinical remission with pharmacologic therapy, most patients will eventually require surgery for their disease. Unfortunately, surgery is not curative and patients still require ongoing therapy even after surgery for disease recurrence. Importantly, given the risks of complications from both Crohn disease and the medications used to treat the disease process, primary care physicians play an important role in optimizing the preventative care management to reduce the risk of complications.

Anoperineal disease in Hidradenitis Suppurativa : MR imaging distinction from perianal Crohn's disease

OBJECTIVE

To determine whether Hidradenitis suppurativa (HS)-related anoperineal disease can be distinguished from Crohn's disease (CD) using MRI.

METHODS

Pelvic MRI of 23 HS and 46 CD patients with anoperineal disease between 2007 and 2014 were independently analysed by two radiologists. For diagnosis of HS, sensitivity, specificity and positive likelihood ratios (LRs) of inflammatory features and of their anatomical distribution were calculated and compared to those of CD.

RESULTS

In HS, fistulae were less present (P = .033) and less frequently involved the sphincters (P = .001) than in CD. Granulomas were more frequent (P = .0005). For anterior/inguinal and posterior localizations, sensitivity, specificity and LR for diagnosis of HS were 70% (49.1, 84.4), 87% (74.3, 93.9), 5.3 (2.41, 11.79) and 57% (36.8, 74.4), 93% (82.5, 97.8), 8.67 (2.74, 27.41), respectively. Combination of signs including posterior involvement, absence of rectal wall thickening and bilaterality of features yielded specificity of 100% (95% CI: 92.3-100) for HS.

CONCLUSION

Although MRI presentations of anoperineal disease may overlap between CD and HS, specific diagnosis of HS is possible with a combination of three features: absence of features' predominance in perianal area, absence of rectal wall thickening and bilaterality of features.

KEY POINTS

• Spectrum of MRI features of HS-related anoperineal disease is wide. • Specific diagnosis of HS-related anoperineal disease is possible using MR imaging. • A combination of three MR signs allows distinction between HS and CD.

Using computed tomography enterography to evaluate patients with Crohn's disease: what impact does examiner experience have on the reproducibility of the method?

Objective

To assess the impact that examiner experience has on the reproducibility and accuracy of computed tomography (CT) enterography in the detection of radiological signs in patients with Crohn's disease.

Materials and Methods

This was a retrospective, cross-sectional observational study involving the analysis of CT enterography scans of 20 patients with Crohn's disease. The exams were analyzed independently by two radiologists in their last year of residence (duo I) and by two abdominal imaging specialists (duo II). The interobserver agreement of each pair of examiners in identifying the main radiological signs was calculated with the kappa test. The accuracy of the examiners with less experience was quantified by using the consensus among three experienced examiners as a reference.

Results

Duo I and duo II obtained a similar interobserver agreement, with a moderate to good correlation, for mural hyperenhancement, parietal thickening, mural stratification, fat densification, and comb sign (kappa: 0.45-0.64). The less experienced examiners showed an accuracy > 80% for all signs, except for lymph nodes and fistula, for which it ranged from 60% to 75%.

Conclusion

Less experienced examiners have a tendency to present a level of interobserver agreement similar to that of experienced examiners in evaluating Crohn's disease through CT enterography, as well as showing satisfactory accuracy in identifying most radiological signs of the disease.

Feasibility of CEUS and strain elastography in one case of ileum Crohn stricture and literature review

Contrast-enhanced ultrasonography (CEUS) and strain elastography (SE) are diagnostic imaging methods, which are still not routinely used in the clinical management of inflammatory bowel diseases. However, there are studies in the literature reporting on the use of both CEUS and SE in patients with bowel obstruction due to Crohn's disease, documenting the usefulness of these two methods in the differentiation between inflammation and fibrosis affecting the bowel wall. The aim of this case report is to evaluate the usefulness of CEUS and SE performed in a patient with Crohn's disease, who was admitted to hospital with bowel obstruction due to terminal ileal stricture and submitted to ileocecal resection. CEUS and SE identified and to some extent also characterized the inflammatory and fibrotic processes affecting the bowel wall. Macroscopic and microscopic examinations of the surgical specimen confirmed the presence of inflammatory phenomena (exudates, ulcers, and fistulas) and fibrosis as suggested by ultrasound (US) imaging methods.

Quantitative Contrast-Enhanced Ultrasound Parameters in Crohn Disease: Their Role in Disease Activity Determination With Ultrasound

OBJECTIVE

The primary objective of our study was to examine the association between contrast-enhanced ultrasound (CEUS) parameters and established gray-scale ultrasound with color Doppler imaging (CDI) for the determination of disease activity in patients with Crohn disease. Our secondary objective was to develop quantitative time-signal intensity curve thresholds for disease activity.

MATERIALS AND METHODS

One hundred twenty-seven patients with Crohn disease underwent ultrasound with CDI and CEUS. Reviewers graded wall thickness, inflammatory fat, and mural blood flow as showing remission or inflammation (mild, moderate, or severe). If both gray-scale ultrasound and CDI predicted equal levels of disease activity, the studies were considered concordant. If ultrasound images suggested active disease not supported by CDI findings, the ultrasound results for disease activity were indeterminate. Time-signal intensity curves from CEUS were acquired with calculation of peak enhancement (PE), and AUCs. Interobserver variation and associations between PE and ultrasound parameters were examined. Multiclass ROC analysis was used to develop CEUS thresholds for activity.

RESULTS

Ninety-six (76%) studies were concordant, 19 of which showed severe disease, and 31 (24%) studies were indeterminate. Kappa analyses revealed good interobserver agreement on grades for CDI (κ = 0.76) and ultrasound (κ = 0.80) assessments. PE values on CEUS and wall thickness showed good association with the Spearman rank correlation coefficient for the entire population (ρ = 0.62, p < 0.01) and for the concordant group (ρ = 0.70, p < 0.01). Multiclass ROC analyses of the concordant group using wall thickness alone as the reference standard showed cutoff points of 18.2 dB for differentiating mild versus moderate activity (sensitivity, 89.0% and specificity, 87.0%) and 23.0 dB for differentiating moderate versus severe (sensitivity, 90% and specificity, 86.8%). Almost identical cutoff points were observed when using ultrasound global assessment as the reference standard: using 18.2 dB to differentiate mild versus moderate activity yielded sensitivity of 89.2% and specificity of 90.9% and using 22.9 dB to differentiate moderate versus severe activity yielded sensitivity of 89.5% and specificity of 83.1%.

CONCLUSION

Quantitative CEUS parameters integrated into inflammatory assessments with ultrasound reduce indeterminate results and improve disease activity level determinations.

Crohn's disease Activity: Abdominal Computed Tomography Histopathology Correlation

Purpose

Crohn’s disease is a type of inflammatory bowel disease affecting estimated 4 million people worldwide. Therapy stratification of Crohn’s disease (CD) is mainly based on the inflammatory activity being assessed by endoscopic biopsy and clinical criteria. Cross-sectional imaging allows for the assessment of structural characteristics of the entire gastrointestinal tract including small bowel loops and may provide potential non-invasive image-based biomarkers for the inflammatory activity of CD. The aim of this study was to explore the predictive value of Computed Tomography-based morphologic patterns for inflammatory activity in CD.

Material and methods

42 patients diagnosed with CD were included in a retrospective study (13 male, 29 female, median age 32 years). Abdominal CT imaging was carried out on symptomatic patients at a single institution 0–10 days prior to endoscopic biopsy or surgery using a protocol optimized for the characterization of structural bowel alterations. Image data were initially reviewed independently by three radiologists and discrepancies were settled in consensus with a focus on mesenteric fat stranding and combing, mesenteric adenopathy, mesenteric abscess, intraperitoneal free fluid, fistula, skip lesions, highest wall thickness and the localization of the affected bowel. The extent of inflammatory activity in the bowel wall was determined subsequently by histological analysis.

Results

All intestinal and extraintestinal CT findings except the mesenteric comb sign showed a tendency towards higher extent or prevalence in patients with high histological inflammatory activity score, especially median bowel wall thickness (6.0 mm vs. 3.5 mm), mesenteric abscesses (32% vs. 0%) and mesenteric adenopathy (94% vs. 45%). Spearman rank order correlation coefficient indicated a significant correlation of bowel wall thickness (r = 0.40, p < 0.05), mesenteric adenopathy (r = 0.54, p < 0.05), mesenteric abscess (r = 0.33, p < 0.05) and mesenteric fat stranding (r = 0.33, p < 0.05) with the histological inflammatory activity score.

Conclusion

CT-based biomarkers including wall thickness, mesenteric fat stranding, mesenteric lymphadenopathy and mesenteric abscess positively correlated with the histological inflammatory activity score and therefore provided additional information for therapy stratification in symptomatic patients with CD, particularly as most of these biomarkers are hidden from endoscopy.

Quality assurance methodology and applications to abdominal imaging PQI

Quality assurance has increasingly become an integral part of medicine, with tandem goals of increasing patient safety and procedural quality, improving efficiency, lowering cost, and ultimately improving patient outcomes. This article reviews quality assurance methodology, ranging from the PDSA cycle to the application of lean techniques, aimed at operational efficiency, to continually evaluate and revise the health care environment. Alignment of goals for practices, hospitals, and healthcare organizations is critical, requiring clear objectives, adequate resources, and transparent reporting. In addition, there is a significant role played by regulatory bodies and oversight organizations in determining external benchmarks of quality, practice, and individual certification and reimbursement. Finally, practical application of quality principles to practice improvement projects in abdominal imaging will be presented.

Contrast-Enhanced Cross Sectional Imaging and Capsule Endoscopy: New Perspectives for a Whole Picture of the Small Bowel

Small bowel evaluation is a challenging task and has been revolutionized by high-quality contrasted sectional imaging (CT enterography - CTE) and magnetic resonance enterography (MRE) as well as by small bowel capsule endoscopy (SBCE). The decision of which technique to employ during the investigation of small bowel diseases is not always simple or straightforward. Moreover, contraindications may preclude the use of these techniques in some patients, and although they are noninvasive procedures, may present with various complications. SBCE plays a crucial role in the investigation of both obscure gastrointestinal bleeding and Crohn's disease, but it is also useful for surveillance of patients with Peutz-Jeghers syndrome, while CTE is very accurate in small bowel tumours and in established Crohn's Disease, and its use in patients presenting with gastrointestinal bleeding is increasing. MRE, an expensive and not widely available technique, is essential for the study of patients with Crohn's Disease, and presents an attractive alternative to SBCE in Peutz-Jeghers syndrome surveillance. These diagnostic modalities are often not competitive but synergistic techniques. Knowing their characteristics, strengths and limitations, indications, contraindications and potential complications, as well as the adaptation to local availability and expertise, is essential to better select which procedures to perform in each patient, both safely and effectively, in order to optimize management and improve patient outcomes.

Magnetic Resonance Imaging of the Small Bowel in Crohn's Disease: A Systematic Review and Meta-Analysis

Introduction. Crohn's disease is most commonly found in the terminal ileum and colonic region. Magnetic resonance has become a useful modality for assessing small bowel activity. In this study, we performed a systematic review and meta-analysis on the use of MR in detecting small bowel activity as well as extramural complications in Crohn's patients. Methods. Two independent reviewers sorted through articles until October 2, 2014. We included both studies providing raw data for pooling and studies without raw data. Sensitivity, specificity, likelihood ratios, and 95% confidence intervals were calculated for each study. Results. There were 27 included studies, of which 19 were included in the pooled analysis. Pooled analysis of the 19 studies (1020 patients) with raw data revealed a sensitivity of 0.88 (95% CI 0.86 to 0.91) and specificity was 0.88 (95% CI 0.84 to 0.91). In regard to detecting stenosis, pooled sensitivity was 0.65 (95% CI 0.53 to 0.76) and specificity was 0.93 (95% CI 0.89 to 0.96). Conclusion. MR imaging provides a reliable alternative in detecting small bowel activity in patients with Crohn's disease. Its advantages include high diagnostic accuracy and no radiation exposure while its disadvantages include high cost and limited availability.

Prediction of patency capsule retention in known Crohn's disease patients by using magnetic resonance imaging

BACKGROUND AND AIMS

Evaluation of small-bowel patency is recommended before swallowing video capsule endoscopy to prevent capsule retention. This study aimed to evaluate the ability of magnetic resonance enterography (MRE) to predict patency capsule (PC) retention in patients with Crohn's disease and to identify the most predictive imaging features for retention.

METHODS

Fifty-seven patients prospectively underwent MRE and PC. Two radiologists predicted PC retention. Interrater reliability was determined by using Cohen's κ coefficient. The sensitivity, specificity, and positive and negative predictive values were calculated for the predictions. Evaluation of the imaging features was done using the t test and receiver-operating characteristics; t-tests were also performed on the clinical parameters.

RESULTS

The κ value for interrater reliability was 0.58. The sensitivity, specificity, PPV, and NPV for the predictions by the 2 radiologists were 92.3%, 59%, 40%, 96.3%, and 100%, 52.3%, 38.2%, 100%, respectively. The maximal stricture length (9.7 ± 3.66 cm vs 7.0 ± 3.08 cm, P = .04) and the number of prestenotic dilations (1.9 ± 1.07 vs 1.0 ± 1.38, P = .03) were associated with PC retention. The area under the receiver-operating characteristic curves was 0.69 for the maximal stricture length and 0.751 for the number of prestenotic dilations. The phenotype of the disease was the only clinical parameter significantly correlated with PC retention.

CONCLUSIONS

MRE has a high NPV and sensitivity for PC retention. When capsule retention is suggested by MRE, PC should be performed before the video capsule endoscopy examination. The maximal stricture length and the number of prestenotic dilations were found to be the most predictive imaging features for PC retention.

Utility of Emergency Department Use of Abdominal Pelvic Computed Tomography in the Management of Crohn's Disease

GOAL

The primary aim of this study was to determine predictors of clinically significant computed tomography (CT) scans, paying particular attention to findings of previous CT scans.

BACKGROUND

Use of CT to assess patients with Crohn's disease (CD) in the Emergency Department (ED) is both costly and exposes patients to high levels of ionizing radiation while not clearly improving outcomes.

STUDY

Patients with CD who underwent CT scan in the Emergency Department from 2008 to 2011 at a tertiary referral center were assessed for clinically significant findings. A multivariable generalized estimating equation model with logit link and exchangeable working correlation structure was constructed to assess for independent predictors of CT scans with clinically significant findings.

RESULTS

A total of 118 patients with CD underwent 194 CT scans. Ninety-two of 194 (47%) CT scans demonstrated clinically significant findings. Predictors of clinically significant CT scans included ileal disease involvement [odds ratios (OR) 3.47, P=0.01] and white blood cell count >12 (OR 2.1, P=0.03). Most notably, patients with a CT scan without clinically significant findings performed in the preceding month were significantly less likely to have a clinically significant CT scan (OR 0.23, P=0.005).

CONCLUSIONS

Patients with CD who had a CT scan without significant findings the month prior are unlikely to have clinically significant CT findings. Ileal disease and an elevated white blood cell are predictive of clinically significant CT scans.

Assessment of Disease Activity in Small Bowel Crohn's Disease: Comparison between Endoscopy and Magnetic Resonance Enterography Using MRIA and Modified MRIA Score

Objectives. To retrospectively compare the results of the MRIA (magnetic resonance index of activity) with a modified MRIA (mMRIA), which was calculated excluding from MRIA formula the data of relative contrast enhancement (RCE). Materials and Methods. MR-E and corresponding endoscopic records of 100 patients were reviewed. MRIA, mMRIA, and SES endoscopic index were calculated for all the patients. Namely, MRIA was calculated as follows: (1.5 × wall thickening + 0.02 × RCE + 5 × intramural edema + 10 × ulcers), while mMRIA was calculated with the modified formula (1.5 × wall thickening + 5 × intramural edema + 10 × ulcers). Results. Mean MRIA and mMRIA values were 19.3 and 17.68, respectively (p < 0.0001). A significant correlation (p < 0.0001) was observed between MRIA and mMRIA scores and between both MR indexes and SES (p < 0.0001). Conclusions. mMRIA was comparable to MRIA in the evaluation of disease activity in Crohn's disease.

In vivo evaluation of inflammatory bowel disease with the aid of μPET and the translocator protein 18 kDa radioligand [18F]DPA-714

Purpose

The purpose of the study was to validate [¹⁸F]DPA-714, a translocator protein (TSPO) 18 kDa radioligand, as a probe to non-invasively quantify the inflammatory state in inflammatory bowel disease (IBD) animal models.

Procedures

Quantitative positron emission tomography (PET) imaging of intestinal inflammation was conducted with 2-deoxy-2-[¹⁸F]fluoro-D-glucose ([¹⁸F]FDG) a glucose metabolism surrogate marker and [¹⁸F]DPA-714 a ligand of the 18 kDa TSPO, on two IBD models. The first model was induced using dextran sodium sulfate (DSS), creating global inflammation in the colon. The second model was induced by rectally administering trinitrobenzenesulfonic acid (TNBS), creating local and acute inflammation.

Results

The level of inflammation was analyzed using PET imaging on days 7 and 8. The analysis obtained with [¹⁸F]DPA-714, yielded a significant difference between the DSS treated (0.50 ± 0.17%ID/cc) and non-treated rats (0.35 ± 0.15%ID/cc). [¹⁸F]FDG on the other hand did not yield a significant difference. We did observe a mean glucose consumption in the colon increase from 0.40 ± 0.11 %ID/cc to 0.54 ± 0.17 %ID/cc. In the TNBS model, the uptake level of [¹⁸ F]DPA-714 increased significantly from 0.46 ± 0.23%ID/cc for the non-treated group, to 1.30 ± 0.62%ID/cc for those treated. PET signal was correlated with increased TSPO expression at cellular level.

Conclusions

Results indicate that [¹⁸F]DPA-714 is suitable for studying inflammation in IBD models. [¹⁸F]DPA-714 could be a good molecular probe to non-invasively evaluate the level and localization of inflammation. Moreover, in vivo imaging using this TSPO ligand is potentially a powerful tool to stage and certainly to follow the evolution and therapeutic efficiency at molecular level within this disease family.

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.

Assessment of Inflammation in an Acute on Chronic Model of Inflammatory Bowel Disease with Ultrasound Molecular Imaging

BACKGROUND

Ultrasound (US) molecular imaging has shown promise in assessing inflammation in preclinical, murine models of inflammatory bowel disease. These models, however, initiated acute inflammation on previously normal colons, in contrast to patients where acute exacerbations are often in chronically inflamed regions. In this study, we explored the potential of dual P- and E-selectin targeted US imaging for assessing acute inflammation on a murine quiescent chronic inflammatory background.

METHODS

Chronic colitis was induced using three cycles of 4% DSS in male FVB mice. Acute inflammation was initiated 2 weeks after the final DSS cycle through rectal administration of 1% TNBS. Mice at different stages of inflammation were imaged using a small animal ultrasound system following i.v. injection of microbubbles targeted to P- and E-selectin. In vivo imaging results were correlated with ex vivo immunofluorescence and histology.

RESULTS

Induction of acute inflammation resulted in an increase in the targeted US signal from 5.5 ± 5.1 arbitrary units (a.u.) at day 0 to 61.0 ± 45.2 a.u. (P < 0.0001) at day 1, 36.3 ± 33.1 a.u. at day 3, returning to levels similar to control at day 5. Immunofluorescence showed significant increase in the percentage of P- and E-selectin positive vessels at day 1 (P-selectin: 21.0 ± 7.1% of vessels; P < 0.05; E-selectin: 16.4 ±3.7%; P < 0.05) compared to day 0 (P-selectin: 10.3 ± 5.7%; E-selectin: 7.3 ± 7.0%).

CONCLUSIONS

Acute inflammation can be accurately measured in a clinically relevant murine model of chronic IBD using ultrasound molecular imaging with a dual P- and E- selectin-targeted contrast agent.

Advances in imaging to allow personalized medicine in Crohn's disease

Crohn's disease is a destructive inflammatory bowel disease of unknown origin that may lead to various complications such as strictures, stenosis, fistulas and colitis-associated neoplasias. However, the course of the disease varies substantially among patients and disease behaviour may also change with time. At diagnosis behaviour is inflammatory in the majority of patients, while penetrating or structuring behaviour become more prominent at later time points. Thus, medication in Crohn's disease needs frequent optimization over time. Therefore, new strategies for prediction of response to therapy are urgently needed. Here, recent advantages in imaging techniques for personalized medicine in Crohn's disease are reviewed. Such advantages include ultrasonography, computed tomography, magnetic resonance imaging and new endoscopic approaches such as molecular endoscopy. It is expected that these novel techniques will lead to marked improvements in the assessment of disease behaviour and the prediction of response to clinical therapy with biologicals.