Clinical utility of small bowel ultrasound assessment of Crohn's disease in adults: a systematic scoping review

Substantial cost savings of ultrasound-based management over magnetic resonance imaging-based management in an inflammatory bowel disease service

BACKGROUND

Imaging is used to monitor disease activity in small bowel Crohn's disease (CD). Magnetic Resonance Enterography is often employed as a first modality in the United Kingdom for assessment and monitoring; however, waiting times, cost, patient burden and limited access are significant. It is as yet uncertain if small bowel intestinal ultrasound (IUS) may be a quicker, more acceptable, and cheaper alternative for monitoring patients with CD.

METHODS

A clinical service evaluation of imaging pathways was undertaken at a single NHS site in England, United Kingdom. Data were collected about patients who were referred and underwent an imaging analysis for their IBD. Only patients who underwent a therapy change were included in the analysis. Data were collected from care episodes between 01 January 2021-30 March 2022.

RESULTS

A combined total of 193 patient care episodes were reviewed, 107 from the IUS pathway and 86 from the MRE pathway. Estimated costs per patient in the IUS pathway was £78.86, and £375.35 per patient in the MRE pathway. The MRE pathway had an average time from referral to treatment initiation of 91 days (SD= ±61) with patients in the IUS pathway waiting an average of 46 days (SD= ±17).

CONCLUSIONS

Findings from this work indicate that IUS is a potential cost-saving option when compared to MRE when used in the management of CD. This is in addition to the cost difference of the radiological modalities. A large, multicentre, prospective study is needed to validate these initial findings.

Inflammatory bowel disease: recent developments

Paediatric-onset inflammatory bowel disease (IBD) is a complex and heterogenous condition. Incidence of disease in those aged <18 years has doubled over the last 25 years, with concurrent increased prevalence and no decrease in disease severity. The tools available at diagnosis for investigation have developed over the last 10 years, including better utilisation of faecal calprotectin, improved small bowel imaging and video capsule endoscopy. Alongside this, management options have increased and include biological and small molecule therapies targeting alternative pathways (such as interleukin 12/23, integrins and Janus kinase/signal transducers and activators of transcription, JAK-STAT pathways) and better understanding of therapeutic drug monitoring for more established agents, such as infliximab. Dietary manipulation remains an interesting but contentious topic.This review summarises some of the recent developments in the diagnosis, investigation and management of IBD in children and young people. IBD is increasingly recognised as a continuum of disease, with a proportion of patients presenting with classical Crohn's disease or ulcerative colitis phenotypes. Future implementation of personalisation and stratification strategies, including clinical and molecular biomarkers, implementation of predictors of response and outcome and use of additional therapies, will continue to require working within clinical networks and multiprofessional teams.

Stakeholder-identified barriers and enablers to ultrasound implementation in inflammatory bowel disease services in the UK: a qualitative interview study

OBJECTIVES

The study sought to explore and better understand the perceptions and experiences of stakeholders in relation to the use of ultrasound for the assessment of inflammatory bowel disease (IBD) in adults in the UK.

DESIGN

A qualitative semistructured interview study, using template analysis and normalisation process theory, was undertaken.

SETTING

Interviews were conducted using virtual meeting software.

RESULTS

Fourteen participants were enrolled between 2nd of June 2021 and 6th of September 2021. Participants were from the following roles: medical gastroenterology and radiology doctors, IBD nurse specialists, patients living with IBD, healthcare service managers. Participants reported that perceived barriers included reliance on established imaging and care pathways, reluctance to change, lack of trust in ultrasound in relation to perceived lack of precision and the initial financial and time outlay in establishing an ultrasound service. Participants were enthusiastic for the uptake of ultrasound and discussed enablers to ultrasound uptake including the benefits to patients in terms of reduction in waiting times and earlier diagnosis and treatment allocation, reduced number of hospital appointments and patients having better understanding of their health.

CONCLUSION

There are perceived barriers to achieving implementation of ultrasound. There is scant literature to effectively assess these reported barriers. Therefore, there is further research required in the areas of the impact of the use of ultrasound for the assessment of IBD in the UK.

Role of abbreviated non-contrast-enhanced MR-enterography in the evaluation of Crohn's disease activity and complications as an alternative for full protocol contrast-enhanced study: A systematic review and meta-analysis

Background

Crohn's disease (CD) is a chronic disorder that often starts at a young age and involves periods of remission and relapse. Prompt diagnosis of relapses through screening is crucial due to the potential morbid complications of untreated active inflammation. Magnetic resonance enterography (MRE) is a noninvasive technique to screen for active inflammation. The standard protocol involves intravenous injection of contrast agents with potential side effects. Some abbreviated non-contrast-enhanced MRE protocols are proposed as alternatives for conventional MRE to identify active inflammation. Currently, there is controversy regarding the applicability and accuracy of these protocols. This study aims to describe and compare these protocols and evaluate their accuracy in detecting active inflammation and CD complications.

Methods

Results from a systematic search of three databases in August 2022 were queried and screened by abstract and full text. Eligible studies were qualitatively and quantitatively analyzed by diagnostic test accuracy meta-analysis.

Results

59 studies entered the systematic review, and 37 were eligible for meta-analysis. Diffusion-weighted imaging (DWI) and fast T2-weighted (T2w) sequences were most frequently used in abbreviated protocols and showed non-inferior accuracy compared to the full protocol in detecting active inflammation. ADC and qualitative DWI had pooled sensitivity of 90% (CI: 82-95%) and 89% (CI:82-93%) and pooled specificity of 94% (CI: 88-97%) and 89% (CI: 79-94%), respectively for detecting active inflammation. Moreover, T2w and combined T2w+DWI sequences had pooled sensitivity of 80% (CI: 64-90%) and 76% (CI: 61-86%) and pooled specificity of 90% (CI: 80-95%) and 87% (CI: 74 - 94%), respectively. Unenhanced protocols show relatively poor diagnostic accuracy in detecting penetrating complications of CD. Magnetization transfer imaging (MTI) has demonstrated excellent accuracy in detecting fibrosis. High heterogeneity was observed in all subgroups, and accuracy was reported to be highly operator dependent in most studies.

Conclusion

An abbreviated protocol consisting of DWI and fast T2w imaging can potentially replace the full protocol MRE. Full protocol MRE will still have its role in identifying penetrating complications. MTI should be indicated in case of suspected fibrostenotic disease.

The Role of Endoscopy in the Diagnosis and Management of Small Bowel Pathology in Children

Small bowel evaluation has been transformed by capsule endoscopy and advances in small bowel imaging, which provide reliable and noninvasive means for assessing the mucosal surface. Device-assisted enteroscopy has been critical for histopathological confirmation and endoscopic therapy for a wide range of small bowel pathology that conventional endoscopy cannot reach. The purpose of this review is to provide a comprehensive overview of the indications, techniques, and clinical applications of capsule endoscopy; device-assisted enteroscopy; and imaging studies for small bowel evaluation in children.

Positioning intestinal ultrasound in a UK tertiary centre: significant estimated clinical role and cost savings

OBJECTIVE

Intestinal ultrasound (IUS) is an inexpensive, non-invasive method of diagnosing and monitoring inflammatory bowel disease (IBD). We aimed to establish the proportion of lower gastrointestinal endoscopies (LGIEs) and magnetic resonance enterographies (MREs) that could have been performed as IUS, the potential pathology miss-rates if IUS was used and the associated cost savings.

METHODS

All MREs and LGIEs performed for either assessment of IBD activity or investigation of possible IBD, performed at a single UK tertiary centre in January 2018, were retrospectively reviewed against predetermined criteria for IUS suitability. Case outcomes were recorded and cost of investigation if IUS was performed instead was calculated.

RESULTS

73 of 260 LGIEs (28.1%) and 58 of 105 MREs (55.2%) met the criteria for IUS suitability. Among potential IUS-suitable endoscopy patients, one case each of a <5 mm adenoma and sessile serrated lesion were found; no other significant pathology that would be expected to be missed with IUS was encountered. Among IUS-suitable MRE patients, no cases of isolated upper gastrointestinal inflammation likely to be missed by IUS were found, and extraintestinal findings not expected to be seen on IUS were of limited clinical significance. The predicted cost saving over 1 month if IUS was used instead was £8642, £25 866 and £5437 for MRE, colonoscopy and flexible sigmoidoscopy patients, respectively.

CONCLUSION

There is a significant role for IUS, with annual projected cost savings of up to almost £500 000 at our centre. Non-inflammatory or non-gastrointestinal pathology predicted to be missed in this cohort was of limited clinical significance.

Imaging in inflammatory bowel disease: current and future perspectives

The use of cross-sectional imaging and ultrasonography has long complemented endoscopic assessment of inflammatory bowel disease (IBD). Clinical symptoms alone are often not enough to assess disease activity, so a reliance on non-invasive techniques is essential. In this paper, we aim to examine the current use of radiological modalities in aiding the management of patients with IBD. We focus on the various sections of the gastrointestinal tract and how different modalities can aid in assessing current disease state and response to treatments. We also have a look at how newer sequences in cross-sectional imaging and ultrasonography can allow for better differentiation of disease activity (ie, fibrotic vs inflammatory) as well improve evaluation of small bowel, colonic and perianal disease. Furthermore, we examine how advanced image processing has the potential to allow radiology to be a surrogate for biomarkers. An example of this is explored when reviewing the ability of MR sequences to quantify visceral fat, which potentially plays a role in determining disease activity in Crohn's disease. Lastly, we look into the expected role for artificial intelligence to be used as an adjunct to radiology to better improve IBD evaluation.