Assessment of activity of Crohn's disease of the ileum and large bowel: proposal for a new multiparameter MR enterography score

Comparison of Magnetic Resonance Enterography Global Score (MEGS) with indices of Crohn's disease activity in South Asian population

PURPOSE

Assessment of disease activity in Crohn's helps predict important clinical outcomes. Among the various modalities available to assess disease activity, magnetic resonance enterography (MRE) is considered a safe and reliable imaging option. Various MRE-based scoring systems have been developed to measure disease activity, one of which being the MRE global score (MEGS). We aimed to correlate MEGS with some of the important indices of Crohn's disease activity.

METHODOLOGY

Crohn's disease patients referred for MRE were included in the study. Along with demographic profile and relevant investigations, MRE parameters related to MEGS were also assessed.

RESULT

A total of 47 patients were recruited for the study. Their median age was 34 years (range 18-68 years), and male:female ratio was 16:31. There was modest positive correlation between MEGS and faecal calprotectin (r = 0.3, p = 0.04), CRP level (r = 0.34, p = 0.02) and Harvey Bradshaw index (r = 0.3, p = 0.043), respectively. However, there was strong correlation between segmental MEGS and Simple Endoscopic Score in those with terminal ileal disease (r = 0.81, p < 0.001). Mural thickness was the only MRE parameter that correlated with active disease (OR - 1.35, 95% CI 1.01, 1.81, p = 0.041) on multivariate analysis. There was moderate inter-observer agreement (Lin's r = 0.78, p < 0.001).

CONCLUSION

MEGS showed modest correlation with indices of Crohn's disease activity which corroborates the complementary role of MRE in management of such patients.

Prevalence and clinical significance of incidental extra-intestinal findings in MR enterography: experience of a single University Centre

PURPOSE

To determine the incidence and clinical relevance of extra-intestinal incidental findings (IF) in a cohort of patients with proven or suspected Crohn disease (CD) examined with magnetic resonance enterography (MR-E) in a single University Centre.

METHODS

Between January 2018 and June 2019, 182 patients with proven or suspected CD with a planned first MR-E examination, were retrospectively included in this study. Incidental findings were considered as any abnormality identified in the absence of previous clinically suspected or known disease. IF were categorized as unremarkable, benign or potentially relevant findings requiring further imaging or specific treatment.

RESULTS

Of the 182 revised MR-E, extra-intestinal IF were recorded in 70 cases (38.5%); 35 (50%) incidental lesions were recognized as non-significant, 24 (34%) as benign and 11 (16%) as clinically relevant. Moreover, there was a positive correlation between IF and patients' age (p < 0.0001).

CONCLUSIONS

In our experience, a high number of IF (38.5%) was found, with a prevalence that increases with patients' age. Clinically relevant findings were found in 16% of MR-E. This means that MR-E is a useful tool to detect IF, therefore, the presence of a radiologist during the image acquisition is crucial in adding sequences to the examination.

Layered enhancement at magnetic resonance enterography in inflammatory bowel disease: A meta-analysis

BACKGROUND

Documentation of disease activity in patients affected by Crohn’s disease (CD) is mandatory in order to manage patients properly. Magnetic resonance imaging (MRI) is considered the reference cross-sectional technique for the assessment of CD activity. Among MRI findings, layered pattern (LP) of contrast enhancement seems to be one of the most significant signs of severe disease activity; however, it has also been associated with chronic disease and mural fibrosis.

AIM

To systematically evaluate the accuracy of LP of contrast enhancement in the diagnosis of active inflammation in patients with CD.

METHODS

In February 2019, we searched the MEDLINE and Cochrane Central Register of Controlled Trials databases for studies evaluating the diagnostic accuracy of LP of contrast enhancement on MRI for the detection of active inflammation in patients with CD. To be included, studies had to use histopathologic analysis (endoscopy or surgery) as the reference standard. Risk of bias and applicability concerns of the included studies were evaluated by using items from the Quality Assessment for Diagnostic Accuracy Studies 2 (QUADAS-2) tool. Pooled sensitivity and specificity were determined using a bivariate random-effect model. Heterogeneity was quantified by using the I² statistic. Our meta-analysis received no funding, and the review protocol was not published or registered in advance.

RESULTS

Of the 1383 studies identified, five articles were finally selected for quantitative and qualitative synthesis (245 patients, 238 of whom had histopathologically confirmed CD, 144 with active inflammation and 94 with inactive disease). The meta-analysis showed a pooled sensitivity of 49.3% (95%CI: 41%-57.8%; I²: 90.7%) and specificity of 89.1% (95%CI: 81.3%- 94.4%; I²: 48.6%). Pooled PLR and NLR were 3.3 (95%CI: 1.9-5.7; I²: 6.1%) and 0.6 (95%CI: 0.5-0.9; I² 70.5%), respectively. SDOR was 6.8 (95%CI: 2.6-17.6; I²: 27.1%). The summary ROC curve showed an area under the curve (AUC) of 0.82 (SE 0.06; Q* 0.76). High risk of bias and applicability concerns were observed in the domains of patient selection for one included study.

CONCLUSION

LP on contrast-enhanced MRI is a specific finding to rule out active inflammation in patients with CD. Further studies using a prespecified definition of LP on contrast-enhanced MRI are needed to support our findings.

Magnetic resonance imaging and Crohn’s disease endoscopic index of severity: Correlations and concordance

AIM

To examine the correlation between magnetic resonance imaging (MRI) and endoscopic index of severity (CDEIS) in patients with Crohn’s disease (CD).

METHODS

This was a retrospective study of 104 patients with CD that were treated at the Ruijin Hospital between March 2015 and May 2016. Among them, 61 patients with active CD were evaluated before/after treatment. MRI and endoscopy were performed within 7 d. CDEIS was evaluated. MRI parameters included MaRIA scores, total relative contrast enhancement (tRCE), arterial RCE (aRCE), portal RCE (pRCE), delay phase RCE (dRCE), and apparent diffusion coefficient. The correlation and concordance between multiple MRI findings and CDEIS changes before and after CD treatment were examined.

RESULTS

Among the 104 patients, 61 patients were classified as active CD and 43 patients as inactive CD. Gender, age, disease duration, and disease location were not significantly different between the two groups (all P > 0.05). CRP levels were higher in the active group than in the inactive group (25.12 ± 4.12 vs 5.14 ± 0.98 mg/L, P < 0.001). Before treatment, the correlations between CDEIS and MaRIAs in all patients were r = 0.772 for tRCE, r = 0.754 for aRCE, r = 0.738 for pRCE, and r = 0.712 for dRCE (all MaRIAs, P < 0.001), followed by MRI single indexes. Among the active CD patients, 44 cases were remitted to inactive CD after treatment. The correlations between CDEIS and MaRIAs were r = 0.712 for aRCE, r = 0.705 for tRCE, r = 0.685 for pRCE, and r = 0.634 for dRCE (all MaRIAs, P < 0.001).

CONCLUSION

Arterial MaRIA should be an indicator for CD follow-up and dynamic assessment. CD treatment assessment was not completely concordant between CDEIS and MRI.

A review of magnetic resonance enterography-based indices for quantification of Crohn's disease inflammation

Magnetic resonance enterography (MRE) is a leading radiological modality in Crohn's disease (CD) and is used together with laboratory findings and endoscopic examinations for the evaluation of patients during initial diagnosis and follow up. Over the years, there has been great progress in the understanding of CD and there is a continuous strive to achieve better monitoring of patients and to develop new modalities which will predict disease course and thus help in clinical decisions making. An objective evaluation of CD using a quantification score is not a new concept and there are different clinical, endoscopies, radiological and combined indices which are used in clinical practice. Such scores are a necessity in clinical trials on CD for evaluation of disease response, however, there is no consensus of the preferred MRE score and they are not routinely used. This review presents MRE-based indices in use in the last decade: the Magnetic Resonance Index of Activity (MaRIA), the Clermont score, the Crohn's Disease Magnetic Resonance Imaging (MRI) Index (CDMI), the Magnetic Resonance Enterography Global Score (MEGS) and the Lemann index. We compare the different indices and evaluate the clinical research that utilized them. The aim of this review is to provide a reference guide for researchers and clinicians who incorporate MRE indices in their work. When devising future indices, accumulated data of the existing indices must be taken into account, as each of the current indices has its own strengths and weakness.

The Diagnostic Accuracy of Sonography, With Graded Compression to Image Acute Appendicitis Compared to Histopathologic Results

Acute appendicitis is the most common surgical abdominal emergency. Its clinical diagnosis remains a challenge to surgeons, so different imaging options were introduced to improve diagnostic accuracy. Among these imaging modality choices, diagnostic medical sonography (DMS) is a simple, easily available, and cost effective clinical tool. The purpose of this study was to assess the accuracy of DMS, in the diagnosis of acute appendicitis compared to the histopathology report, as a gold standard. Between May 2015 and May 2016, 215 patients with suspected appendicitis were examined with DMS. The DMS findings were recorded as positive and negative for acute appendicitis and compared with the histopathological results, as a gold standard. In all, 173 patients were correctly diagnosed as having acute appendicitis by DMS out of 200 cases, with a final histopathologic result. Similarly, DMS revealed 13 normal appendices out of 15 nonappendicitis patients. This demonstrated that DMS has a sensitivity of 86.5%, specificity of 86.6%, positive predictive value of 99.8%, negative predictive value of 32.5%, and overall accuracy of 86.5%. These results suggest that DMS may be an accurate, sensitive, and specific tool for diagnosing acute appendicitis and reducing unnecessary appendectomies. DMS should be considered as a credible imaging modality for diagnosing acute appendicitis.

Diffusion-weighted MRI Enables to Accurately Grade Inflammatory Activity in Patients of Ileocolonic Crohn's Disease: Results from an Observational Study

BACKGROUND

Diffusion-weighted imaging (DWI) is a novel technique to evaluate bowel inflammation in Crohn's disease (CD). It remains unclear whether DWI could differentiate grades of inflammation activity and add to the accuracy of conventional magnetic resonance enterography (MRE) in defining disease activity. We aimed to assess the accuracy of DWI for evaluating ileocolonic CD inflammation compared with conventional MRE, using ileocolonoscopy as reference standard.

METHODS

This was an observational study of CD patients who underwent both ileocolonoscopy and MRE with DWI. The conventional MRE and DWI findings of the ileocolon were scored from 0 to 3. The respective segment endoscopic disease activity was scored by simplified endoscopic score for Crohn's disease (SES-CD) and was graded as inactive (0-2), mild (3-6) or moderate-severe (≥7).

RESULTS

One hundred eighty-five bowel segments from 43 consecutive CD patients were evaluated and included inactive (n = 86), mild (n = 72), and moderate-severe (n = 27) ileo-colonic segments. The area under the receiver operating characteristics curve (AUC) of 0.973 for apparent diffusion coefficient (ADC) to differentiate active from inactive CD was significantly higher than those of conventional MRE parameters (AUC between 0.840 and 0.940). Higher accuracy of ADC (AUC = 0.919) for differentiating inactive-mild from moderate-severe CD was also shown compared with that of conventional MRE parameters (AUC between 0.868 and 0.915). ADC values demonstrated strongest correlation with SES-CD (r = -0.880) comparing to DWI SI and conventional MRE parameters (r between 0.787 and 0.867).

CONCLUSIONS

DWI enables to accurately grade inflammatory activity in patients of ileocolonic CD and may be better suited than conventional MRE for monitoring the activity of CD.

E3 Ubiquitin ligase RNF183 Is a Novel Regulator in Inflammatory Bowel Disease

BACKGROUND AND AIMS

Specific members of the RING finger [RNF] protein family serve as E3 ubiquitin ligases and play important roles in the regulation of inflammation. However, their roles in the pathogenesis of inflammatory bowel disease [IBD] have not been explored.

METHODS

Genomic microarray of inflamed colon samples from Crohn's disease [CD] patients was performed to identify potential up-regulated genes. Expression of the identified highly up-regulated RNF183 gene was subsequently examined by quantitative reverse transcription polymerase chain reaction [qRT-PCR], western blotting and immunohistochemistry of the intestinal tissues of IBD patients and the colons of trinitrobenzene sulphonic acid [TNBS]-induced colitic mice. RNF183-mediated interaction with the NF-κB pathway and ubiquitination of IκBα were examined by siRNA, plasmid transfection, and immunoprecipitation. The miRNA predicted to target RNF183 was explored and its role in the RNF183/ NF-κB pathway was investigated.

RESULTS

RNF183 was up-regulated in intestinal epithelial cells in IBD patients and in colitic mice. RNF183 promoted intestinal inflammation via the activation of the NF-κB pathway by increasing the ubiquitination and degradation of IκBα. Computational analysis identified putative binding of miR-7 to RNF183. Transfection of intestinal cells with a miR-7 mimic or inhibitor confirmed its negative regulatory effect on RNF183 expression and ubiquitination of IκBα. miR-7 was down-regulated in inflamed colon tissues of IBD patients and colitic mice.

CONCLUSIONS

RNF183, which is negatively regulated by miR-7, is a novel regulator promoting intestinal inflammation by increasing the ubiquitination and degradation of IκBα, thereby inducing NF-κB activation. The interaction between RNF183-mediated ubiquitination and miRNA may be an important novel epigenetic mechanism in the pathogenesis of IBD.

Magnetic resonance enterography changes after antibody to tumor necrosis factor (anti-TNF) alpha therapy in Crohn's disease: correlation with SES-CD and clinical-biological markers

Background

In recent years, the use of MRI in patients with Crohn’s disease (CD) has increased. However, few data are available on how MRI parameters of active disease change during treatment with anti-TNF and whether these changes correspond to symptoms, serum biomarkers, or endoscopic appearance. The aim of this study was to determine the changes over time in MRI parameters during treatment with anti-TNF in patients with CD, and to verify the correlation between MRI score, endoscopic appearance and clinical-biological markers.

Methods

We performed a prospective single centre study of 27 patients with active CD (18 males and 9 females; median age of 27,4 ys; age range, 19–49). All patients underwent ileocolonoscopy and MRI at baseline and 26 weeks after anti-TNF therapy. Endoscopic severity was graded according to the Simple Endoscopic Score for Crohn’s Disease (SES-CD) and Magnetic Resonance Index of Activity (MaRIA) was calculated. Patients underwent clinical evaluation (CDAI) and the C-reactive protein (CRP) level was measured. The associations between variables were assessed with Pearson’s bivariate correlation analysis.

Results

A total of 135 intestinal segments were studied. The median patient age was 27,4 years, 67 % were male and the mean disease duration was 6,1 years. For induction of remission, 18 patients were treated with infliximab and 9 with adalimumab. The mean SES-CD and MaRIA scores significantly changed at week 26 (SES-CD: 14,7 ± 8,9 at baseline vs. 4,4 ± 4,6 at 26 weeks - p < 0.001; MaRIA: 41,1 ± 14,8 at baseline vs. 32,8 ± 11,7 at 26 weeks - p < 0.001). Also the CDAI and serum levels of CRP decreased significantly following treatment (p < 0.001). The overall MaRIA correlated with endoscopic score and with clinical activity (CDAI) both at baseline and at week 26 (p < 0.05). The correlation between overall MaRIA and CRP was significant only at week 26 (p < 0.001).

Conclusions

The MaRIA has a good correlation with SES-CD, a high accuracy for prediction of endoscopic mucosal healing and is a reliable indicator to monitor the use of TNF antagonists in patients with CD.

Magnetic resonance enterography in Crohn's disease: new simple proposal to assess disease activity

PURPOSE

The aim is to determine the accuracy of magnetic resonance enterography (MRE) in evaluating Crohn's disease (CD) activity.

MATERIALS AND METHODS

Seventy-seven patients with CD underwent MRE. The primary analysis was to determine associations between MRE findings, Harvey-Bradshaw Index, and C-reactive protein (CRP), then we have created a new MRE score that it was also correlated with clinical and laboratory data.

RESULTS

MRE score for CD significantly correlates with CRP (P=.003). Significant associations were found between degree of contrast enhancement and CRP (P=.002) and between comb sign and CRP (P=.001).

CONCLUSIONS

These results make MRE an important instrument for evaluation of CD activity.

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.

Assessment of Activity of Crohn Disease by Diffusion-Weighted Magnetic Resonance Imaging

To assess the diagnostic efficacy of diffusion-weighted MR imaging (DWI) for evaluating inflammatory activity in patients with Crohn's disease (CD). A total of 47 CD patients underwent MR enterography (MRE) and DWI using 3 b values of 50, 400, and 800 s/mm. Apparent diffusion coefficients (ADCs) of inflamed and normal bowel wall were calculated. The conventional MRE findings and DWI signal intensities were qualitatively scored from 0 to 3. The correlation between Crohn disease activity index (CDAI) and both ADCs and magnetic resonance imaging scores was analyzed. Receiver-operating characteristic curve analysis was used to determine the diagnostic accuracy of CD activity. Of the 47 patients, 25 were active CD (CDAI≥150) and 22 were inactive (CDAI<150). Diffusion-weighted MR imaging and MRE + DWI scores of active CD were significantly higher than that of inactive CD (both P < 0.001). Apparent diffusion coefficients in inflamed segments of active CD were lower than that of inactive CD (P < 0.001). The DWI scores (r = 0.74, P < 0.001), ADCs (r = -0.71, P < 0.001), MRE scores (r = 0.54, P < 0.001), and MRE + DWI scores (r = 0.66, P < 0.001) were all correlated with CDAI. The areas under the receiver-operating characteristics curves for ADCs, DWI scores, MRE scores, and MRE + DWI scores ranged from 0.83 to 0.98. The threshold ADC value of 1.17 × 10 mm/s allowed differentiation of active from inactive CD with 100% sensitivity and 88% specificity. Diffusion-weighted MR imaging and ADC correlated with CD activity, and had excellent diagnostic accuracy for differentiating active from inactive CD.

Impact of Small Bowel MRI in Routine Clinical Practice on Staging of Crohn's Disease

BACKGROUND AND AIMS

Small bowel visualisation is a complex diagnostic approach, but mandatory for risk stratification and stage-adjusted therapy in Crohn's disease. Current guidelines favour transabdominal ultrasound and small bowel MRI as methods of choice, although their clinical impact in daily practice remains controversial. The aim of this study was to evaluate the diagnostic benefit of small bowel MRI in Crohn's disease according to Montreal Classification, in routine practice.

METHODS

Patients who underwent MR-enterography [MRE] or MR-enteroclysis [MRY] were included in a retrospective single-centre study. MRI findings were correlated with results from clinical work-up and evaluated in terms of [1] diagnostic yield, [2] significant additional information, and [3] alterations in the assessment of disease behaviour and location according to Montreal Classification.

RESULTS

A total of 347 small bowel MRI examinations were analysed [MRE: 49 / MRY: 298]. MRI had an average sensitivity/specificity of 82.5% and 99.9% [positive predictive value: 99.8% / negative predictive value: 91.1%] respectively. In every second patient, new relevant diagnostic information was provided. Incorporation of the MRI results caused significant shifts in Montreal Classification, specifically higher L-levels [+21.2%; p < 0.05] and higher B-levels: [+24.6%; p < 0.05].

CONCLUSIONS

Even in routine practice, small bowel MRI is a powerful and reliable technique in small bowel work-up. Since MRE and MRY presented high diagnostic yields, often detected significant additional information, and significantly caused shifts in Montreal Classification, both techniques are confirmed to be excellent tools in diagnosing and monitoring Crohn's disease in its daily course.

High Spatiotemporal Resolution Dynamic Contrast-Enhanced MR Enterography in Crohn Disease Terminal Ileitis Using Continuous Golden-Angle Radial Sampling, Compressed Sensing, and Parallel Imaging

OBJECTIVE

The purpose of this article was to assess the feasibility of golden-angle radial acquisition with compress sensing reconstruction (Golden-angle RAdial Sparse Parallel [GRASP]) for acquiring high temporal resolution data for pharmacokinetic modeling while maintaining high image quality in patients with Crohn disease terminal ileitis.

MATERIALS AND METHODS

Fourteen patients with biopsy-proven Crohn terminal ileitis were scanned using both contrast-enhanced GRASP and Cartesian breath-hold (volume-interpolated breath-hold examination [VIBE]) acquisitions. GRASP data were reconstructed with 2.4-second temporal resolution and fitted to the generalized kinetic model using an individualized arterial input function to derive the volume transfer coefficient (K(trans)) and interstitial volume (v(e)). Reconstructions, including data from the entire GRASP acquisition and Cartesian VIBE acquisitions, were rated for image quality, artifact, and detection of typical Crohn ileitis features.

RESULTS

Inflamed loops of ileum had significantly higher K(trans) (3.36 ± 2.49 vs 0.86 ± 0.49 min(-1), p < 0.005) and v(e) (0.53 ± 0.15 vs 0.20 ± 0.11, p < 0.005) compared with normal bowel loops. There were no significant differences between GRASP and Cartesian VIBE for overall image quality (p = 0.180) or detection of Crohn ileitis features, although streak artifact was worse with the GRASP acquisition (p = 0.001).

CONCLUSION

High temporal resolution data for pharmacokinetic modeling and high spatial resolution data for morphologic image analysis can be achieved in the same acquisition using GRASP.

Magnetic resonance enterography of Crohn's disease

Magnetic resonance enterography (MRE) has been reported to be a useful modality for the evaluation of luminal inflammation and extraintestinal complications in Crohn's disease (CD). A recent study indicated that the diagnostic ability of MRE was comparable to the diagnostic ability of other devices, such as ileocolonoscopy. MRE can be performed repeatedly because there is no radiation exposure. Therefore, MRE is useful as a method of follow-up for younger patients with established CD. It is useful for evaluating the efficacy of medical treatments, such as biologics. MRE can detect small intestinal lesions even if the endoscope does not pass through the stenosis. The concerns of availability of expertise and the costs associated with MRE should be addressed so MRE can be widely used for CD patients in the near future.

Magnetic resonance enterography in the evaluation of Crohn's disease: a primer for the gastroenterologist

The assessment of disease location, severity, and complications is critical in guiding the choice of Crohn's disease therapy. Cross-sectional imaging studies have therefore had a paramount role in accurately staging Crohn's disease. Traditionally, computed tomography was the test of choice in confirming/excluding strictures, fistulae, and abscesses. Magnetic resonance imaging is now replacing computed tomography because it eliminates radiation risks. This review provides a primer for the gastroenterologist on magnetic resonance enterography in Crohn's disease.

Comprehensive magnetic resonance enterography of Crohn's disease in the pediatric population: technique, interpretation, and management

Magnetic resonance enterography (MRE) plays a critical role in the management of Crohn's disease in the pediatric population. The ability to provide dynamic assessment of disease burden, complications, and therapeutic response without ionizing radiation makes it an ideal tool for younger patients requiring frequent follow-up. With a growing array of available treatment options, a sound understanding of MRE is critical in directing management aimed at curbing the physical and emotional morbidity associated with the lifelong condition. The goal of this article is to provide a practical overview of MRE in the pediatric population. This includes a review of our technique, approach to interpretation, pictorial collection of findings, and discussion of the role MRE plays in management.

Magnetic resonance imaging for follow-up of Crohn's disease

AIM: To investigate the value of magnetic resonance imaging (MRI) in the follow-up of Crohn's disease.

METHODS: Thirty three patients (including 24 men and 9 women) with Crohn's disease diagnosed from June 2007 to August 2013 were analyzed retrospectively. According to the clinical data, the patients were divided into either an active phase group or a chronic phase group. All the patients underwent MRI, and the images were reviewed for the mural thickness, the degree of stenosis of diseased bowel segments, mesenteric lymph nodes, and complications (abscess, inflammatory mass, and fistula). Disease activity was assessed according to a multi-parameter score, and MR findings were compared with clinical data.

RESULTS: Of all patients, 24 were clinically identified to have active disease and 9 to have chronic disease, and MR-E identified active disease in 21 cases and chronic disease in the remaining 12. Using clinical diagnosis as the "gold standard", the sensitivity, specificity, positive predictive value and negative predictive value of MR for the depiction of disease activity of CD were 79.2%, 77.8%, 90.5% and 58.3%, respectively. The diagnostic performance of MRI was well matched with that of clinical diagnosis (Kappa = 0.857, P < 0.05). In all the patients, 26 had two or more than 2 segments of the small bowl involved, 29 had the ileocecal area involved, 8 had enlarged mesareic lymph nodes, 17 had "comb sign", and 12 had fistula. There were significant differences in mural thickness, the degree of stenosis of diseased bowel segments, lymph nodes, "comb sign" and fistula between the active disease group and chronic disease group (P < 0.05 for all).

CONCLUSION: The diagnostic performance of MRE is well matched with clinical diagnosis. MRI is more effective in differentiating fistula and abscess, and more suitable for long-term follow-up.

Accuracy of ultrasonography in the diagnosis of acute appendicitis in adult patients: review of the literature

Background

Ultrasound is a widely used technique in the diagnosis of acute appendicitis; nevertheless, its utilization still remains controversial.

Methods

The accuracy of the Ultrasound technique in the diagnosis of acute appendicitis in the adult patient, as shown in the literature, was searched for.

Results

The gold standard for the diagnosis of appendicitis still remains pathologic confirmation after appendectomy. In the published literature, graded-compression Ultrasound has shown an extremely variable diagnostic accuracy in the diagnosis of acute appendicitis (sensitivity range from 44% to 100%; specificity range from 47% to 99% ). This is due to many reasons, including lack of operator skill, increased bowel gas content, obesity, anatomic variants, and limitations to explore patients with previuos laparotomies.

Conclusions

Graded-compression Ultrasound still remains our first-line method in patients referred with clinically suspected acute appendicitis: nevertheless, due to variable diagnostic accuracy, individual skill is requested not only to perform a successful exam, but also in order to triage those equivocal cases that, subsequently, will have to undergo assessment by means of Computed Tomography.

The role of US examination in the management of acute abdomen

Acute abdomen is a medical emergency, in which there is sudden and severe pain in abdomen of recent onset with accompanying signs and symptoms that focus on an abdominal involvement. It can represent a wide spectrum of conditions, ranging from a benign and self-limiting disease to a surgical emergency. Nevertheless, only one quarter of patients who have previously been classified with an acute abdomen actually receive surgical treatment, so the clinical dilemma is if the patients need surgical treatment or not and, furthermore, in which cases the surgical option needs to be urgently adopted. Due to this reason a thorough and logical approach to the diagnosis of abdominal pain is necessary. Some Authors assert that the location of pain is a useful starting point and will guide a further evaluation. However some causes are more frequent in the paediatric population (like appendicitis or adenomesenteritis) or are strictly related to the gender (i.e. gynaechologic causes). It is also important to consider special populations such as the elderly or oncologic patients, who may present with atypical symptoms of a disease. These considerations also reflect a different diagnostic approach. Today, surely the integrated imaging, and in particular the use of multidetector Computed Tomography (MDCT) has revolutionised the clinical approach to this condition, simplyfing the diagnosis but burdening the radiologists with the problems related to the clinical management. However although CT emerging as a modality of choice for evaluation of the acute abdomen, ultrasonography (US) remains the primary imaging technique in the majority of cases, especially in young and female patients, when the limitation of the radiation exposure should be mandatory, limiting the use of CT in cases of nondiagnostic US and in all cases where there is a discrepancy between the clinical symptoms and negative imaging at US.