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Example of the proposed "fast" protocol in a 40-yearold male patient with confirmed Crohn's disease. While coronal T2-weighted SSH images (a) yields in recognizing and measuring the bowel wall thickening (arrows), axial SPAIR T2-weighted (b) and DWI (c) sequences are suitable in identifying signs of active inflammation and/or intestinal complications.
Source publication
Objective
Magnetic resonance enterography has achieved an increasingly importance in the evaluation of patients with Crohn’s disease, although it is limited by high costs and prolonged scanning times. The aim of our work was to design a “fast” abbreviated MRE protocol and to compare it with the standard one.
Materials and Methods
A single-center r...
Context in source publication
Context 1
... MRE images were anonymized for patient data and all investigators were blinded to patient clinical information. Two radiologists, blinded to case review, were asked to duplicate a simulated "fast" MRE protocol by extrapolating from every MRE dataset three types of sequences: Coronal SSH T2 weighted, axial SPAIR T2 weighted, and axial DWI [ Figure 2]. As result, each patient was anonymously presented twice in two different datasets, one including the standard protocol and one including the abbreviated "fast" MRE protocol. ...
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The small intestine is a challenging organ for clinical and radiological evaluation. The introduction of radiological imaging techniques, which do not significantly disturb patients’ comfort and safety, attempts to obtain an adequate diagnosis and valuable information. The aim is to determine the capabilities and potential of ultrasound, computed t...
Citations
... Additionally, there are concerns about the long-term harmful effects of repeated gadolinium-based contrast agent (GBCA) administration, as it can deposit in the brain and bones, especially in children who may undergo surveillance screening MRE dozens of times throughout their lives [14,15]. Furthermore, the standard protocol has a long acquisition time of up to 45 min, which increases the cost and decreases compliance, particularly in younger patients [16,17]. ...
... To overcome the drawbacks stated earlier, it is recommended to use a shortened MRE protocol with an emphasis on fast T2-w sequences. Half-acquisition turbo spin-echo (HASTE) [18] and balanced steady-state free precession or true fast imaging steady-state free precession (bSSFP/trueFISP) techniques are favored due to their ability to effectively display the bowel wall while also having a shorter acquisition time, which helps to avoid temporal artifacts [16,19]. Moreover, consecutive bSSFP can form animated videos to detect diminished bowel wall motility within inflamed segments [20,21]. ...
... Relevant abbreviated MRE protocols include DWI, T2w sequences such as bSSFP/trueFISP, and any other sequence that does not necessitate the use of GBCA, which might also offer a shorter acquisition time. For instance, A previously proposed abbreviated protocol by Cicero et al. has a 35% shorter acquisition time [16]. However, the accuracy and diagnostic capabilities of alternative sequences are still debated, hindering radiologists from developing globally accepted abbreviated protocols for future recommendations. ...
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.
... Magnetic resonance imaging (MRI) is a radiation-free imaging modality that allows comprehensive evaluation of the bowel loops and the abdominal cavity at the same time. [53][54][55] Similar to CT-scan, 2 MR techniques can be distinguished according to mode of oral contrast medium administration: oral ingestion (MR-enterography) or nasojejunal intubation (MR-enteroclysis). 56 Although the latter permits an improved distention of jejunal loops, it is considered quite uncomfortable and less accepted by the patients. ...
Over recent years, inflammatory bowel diseases have become an issue of increased attention in daily clinical practice, due to both a rising incidence and improved imaging capability in detection. In particular, the diagnosis of Crohn's disease is based on clinical picture, laboratory tests and colonoscopy with biopsy. However, colonoscopic evaluation is limited to the mucosal layer. Thus, imaging modalities play a pivotal role in enriching the clinical picture, delivering information on intestinal and extraintestinal involvement. All the imaging modalities can be employed in evaluation of Crohn's disease patients, each of them with specific strengths as well as limitations. In this wide selection, the choice of a proper diagnostic framework can be challenging for the clinician. Therefore, the aim of this work is to offer an overview of the different imaging techniques, with brief technical details and diagnostic potential related to each intestinal tract.
Small bowel obstruction (SBO) is a common condition encountered by radiologists in the evaluation of patients with abdominal pain, and is an important diagnosis to be comfortable with given substantial associated morbidity and mortality. In this review, we summarize an imaging approach to evaluating patients with suspected SBO, discuss the role of certain imaging modalities such as radiography and small bowel follow through, CT, and MRI, as well as review some common and also less common causes of SBO such as internal hernia. We will also discuss tailoring the imaging approach to address specific clinical questions and special patient populations such as imaging the pregnant patient with suspected SBO, and the inflammatory bowel disease patient.
Intestinal assessment through magnetic resonance imaging is multifaceted and several technical variables have to be taken into account. According to the way of administration of water contrast solution for luminal dilation, two main techniques can be performed for small bowel assessment: MR-Enteroclysis requires the placement of a nasojejunal tube, while MR-Enterography needs oral assumption. Among the different enteric contrast media currently available, the choice usually falls on the biphasic ones. These agents are characterized by hyperintensity on T2-weighted scans and hypointensity on T1-weighted scans, which allow an improved assessment of intestinal walls without any risk of underestimating mural contrast enhancement. Preparation to the exam includes prior fasting and avoidance of sedation. Preference of supine or prone decubitus and administration of spasmolytics are still debated. From the technical point of view, standard protocol mainly consists of multiplanar T2-weighted scans and T1-weighted acquisition with fat saturation obtained after gadolinium injection. Nevertheless, additional acquisitions such as diffusion-weighted imaging, MR fluoroscopy, and cine-MR acquisitions can further help in disease assessment. Furthermore, increased benefits deriving from advanced technical developments, such as magnetization transfer and artificial intelligence, are expected to emerge in the next future.
Radiological assessments of the small and large bowel are essential in daily clinical practice. Over plain film X-ray and ultrasound, cross-sectional techniques are considered the most comprehensive imaging modalities. In fact, computed tomography and magnetic resonance imaging take great advantage of the three-dimensional appraisal and the extensive evaluation of the abdominal cavity, allowing intestinal evaluation as well as detection of extra-intestinal findings. In this context, the chief advantage of computed tomography is the fast scan time, which is crucial for emergency cases. Nonetheless, it is undeniably impaired using ionizing radiation. As the awareness of radiation exposure is a topic of increasing importance, magnetic resonance imaging is not only becoming a mere alternative but also a primary imaging technique used in assessing intestinal diseases. Specifically, the evaluation of the large bowel through MRI can be still considered relatively uncharted territory. Although it has demonstrated superior accuracy in the assessment of some clinical entities from inflammatory bowel disease to rectal carcinoma, its role needs to be consolidated in many other conditions. Moreover, different technical methods can be applied for colonic evaluation depending on the specific disease and segment involved. This article aims to provide a thorough overview of the techniques that can be utilized in the evaluation of the large bowel and a discussion on the major findings in different colonic pathologies of primary interest.
PurposeAbbreviated MRI offers significant advantages in terms of MRI throughput, patient tolerance and expediency, and is being utilized for a variety of abdominopelvic imaging applications. However questions abound with respect to financial and medicolegal treatment of these relatively new protocols.MethodsA review of the relevant literature was performed.ResultsThere is no Current Procedural Terminology code for a “limited” MRI study, but it may not be appropriate to bill an abbreviated study the same as a more comprehensive study. With respect to medicolegal concerns, the risk of liability when missing or misinterpreting medically significant findings due to use of an abbreviated scan will turn on whether abbreviated MRI has become the standard of care.Conclusion
In light of these ambiguities, it would behoove abdominopelvic imagers to advocate for their professional and subspecialty organizations to issue practice parameters/guidelines with respect to the utilization of abbreviated MRI protocols, and for the subspecialty to bill these abbreviated scans at objectively reasonable rates.
Crohn’s disease is a chronic inflammatory condition characterized by a transmural involvement of intestinal walls. Its diagnosis comes from a combination of clinical data, imaging findings and, above all, endoscopy with biopsy results, which are mandatory for achieving a definitive diagnosis. Even so, endoscopy information may be unavailable, for instance due to technical impairments or patient intolerance. On the radiological side, Magnetic Resonance Enterography is currently considered the imaging technique of choice for Crohn’s disease assessment, either at first diagnosis or follow-up. Nevertheless, the lack of radiation exposure as well as invasiveness has made this imaging approach suitable also for the evaluation of a number of small and large bowel diseases over recent years. However, it is important to remember that Magnetic Resonance Imaging findings are non-specific and that a wide overlap exists among Crohn’s disease and other intestinal conditions. The aim of this work was to provide a series of intestinal affections evaluated through Magnetic Resonance Enterography that resemble Crohn’s disease and that can be helpful in avoiding misinterpretation, especially when endoscopy data are missing.
Purpose:
To evaluate the frequency and significance of incidental liver lesions identified on MR enterography (MRE) examinations to determine if dedicated sequences for liver evaluation are necessary in the routine MRE protocol.
Methods:
A retrospective departmental database search identified 353 adult (212 women and 141 men; mean [±SD] age, 41.4 [17.0] years; range 18.1-91.9 years) MRE examinations performed in 2017. Radiology reports were reviewed for the presence and characterization of liver lesions, follow-up recommendation, and known malignancy. Follow-up cross-sectional imaging reports were reviewed for liver lesion stability. A senior abdominal radiologist with expertise in liver imaging categorized liver lesions as benign, indeterminate, or malignant and re-characterized indeterminate lesions using follow-up imaging as benign or malignant.
Results:
Seventy-nine MRE (22.4%) described liver lesions and follow-up imaging was recommended in 4/79 (5.1%). Seventy-six liver lesions (96.2%) were characterized as benign (cysts/hemangiomas) on routine interpretation and expert review. One of these was recommended for follow-up imaging on initial report, which was characterized as hemangioma by expert review. The remaining 3 lesions (3.8%) were characterized as indeterminate both by initial report and expert radiologist review but re-characterized as benign after reviewing follow-up examinations.
Conclusion:
All incidental liver lesions identified on MRE in our cohort were benign. Therefore, additional sequences evaluating the liver are unnecessary for routine MRE.
Absract
Introduction
Crohn’s disease (CD) is a major concern due to relatively high incidence and major complications like stricture or fistulas, often requiring surgical treatment.
In recent years, magnetic resonance enterography (MRE) became a popular method of diagnosis and disease surveillance.
The purpose of this review is to summarize and discuss the major and most recent advances in various aspects of MRE usage in diagnosong Crohn’s disease, and to discuss advances in technique, disease activity monitoring and response to treatment.
Methods
A literature search was performed and relevant publications were included, with emphasis on articles from the past decade.
Areas covered
In this review we have presented articles with major advances in the field of MRE of CD patients such as proper sequence selection, recent advances in scoring of disease activity, differentiation between inflammation and fibrosis, response to treatment and technological advances such as the use of AI.
Expert opinion
The main goal in improving MRE performance will be sequence selection aimed at differenting between inflammation and stricture while shortening the study length adjusted to patient compliance, and developing a standardized scoring system for MRE reporting assisted by artificial intelligence.
Inflammatory bowel diseases include pathologic intestinal conditions of unknown etiology, such as Crohn’s disease and ulcerative colitis. Crohn’s disease consists in a chronic transmural inflammation that can affect any part of the gastrointestinal tract and whose clinical course is characterized by a fluctuation of remission and recurrences, while inflammation in ulcerative colitis involves the solely layer of colonic mucosa. Cross-sectional imaging, and especially magnetic resonance enterography, is able to provide useful information about small bowel lesions as well as intestinal and extra-intestinal complications. However, morphological changes due to surgery can significantly impair the evaluation of small and large bowel, especially considering that the majority of CD patients undergo one or more surgical operations during their lifetime. Therefore, the aim of this work is to summarize the main surgical approaches in inflammatory bowel disease patients and the consequent findings on magnetic resonance enterography.
