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Objective: MRI is increasingly used to evaluate small bowel contractility. The objective of this study was to validate a clinically practical stimulation test (300‐kcal meal) for small bowel motility. Methods: Thirty‐one healthy subjects underwent dynamic MRI to capture global small bowel motility after ±10h fasting, of which 15 underwent bowel preparation consisting of 1 L 2.5% mannitol solution and 16 did not. Each subject underwent (1) a baseline motility scan (2) a food challenge (3) a post‐challenge scan, and (4) second post‐challenge scan (after ±20 minutes). This protocol was repeated within 2 weeks. Motility was quantified using a validated motility assessment technique. Key Results: Motility in prepared subjects at baseline was significantly higher than motility in unprepared subjects (0.36 AU vs 0.18 AU, P < 0.001). In the prepared group, the food challenge produced an 8% increase in motility (P = 0.33) while in the unprepared subjects a significant increase of 30% was observed (P < 0.001). Responses to food remained insignificant (P = 0.21) and significant (P = 0.003), for the prepared and unprepared subjects, respectively, ±20 minutes post food challenge. These results were confirmed in the repeated scan session. Conclusion & Inferences: A significant response to a 300‐kcal meal was measured within 10 minutes in unprepared bowel, supporting the clinical use of this challenge to provoke and assess motility changes. A caloric challenge did not produce an observable increase in motility in mannitol prepared subjects. In this article, we present a practical MRI stimulation test and validate it in both mannitol prepared and unprepared healthy subjects to evaluate the stimulation test and provide guidance on MRI preparation for future MRI motility studies. [ABSTRACT FROM AUTHOR]

Background and Aims: Characteristic magnetic resonance imaging [MRI] features associated with long-term perianal fistula closure are still being discussed. This study evaluated the predictive value of degree of fibrosis and disease activity (MAGNIFI-CD index) at MRI for long-term clinical closure of Crohn's perianal fistulas., Methods: Crohn's disease [CD] patients treated with surgical closure following anti-tumour necrosis factor [anti-TNF] induction or anti-TNF alone for high perianal fistulas as part of a patient preference randomized controlled trial [PISA-II] between 2013 and 2020 with a post-treatment MRI and long-term clinical follow-up data were retrospectively included. Two radiologists scored the degree of fibrosis and MAGNIFI-CD index at pre- and post-treatment MRI. The accuracy of post-treatment MRI findings in predicting long-term clinical closure [12 months after the MRI] was evaluated using receiver operating characteristics [ROC] analysis., Results: Fifty patients were included: 31 female, median age 33 years (interquartile range [IQR] 26-45). Fourteen patients showed a 100% fibrotic fistula at post-treatment MRI, all of which had long-term clinical closure. Median MAGNIFI-CD index at post-treatment MRI was 0 [IQR 0-5] in 25 patients with long-term clinical closure and 16 [IQR 10-20] in 25 patients without. ROC analysis showed an area under the curve of 0.90 (95% confidence interval [CI] 0.82-0.99) for degree of fibrosis and 0.95 [95% CI 0.89-1.00] for the MAGNIFI-CD index, with a Youden cut-off point of 6 [91% specificity, 87% sensitivity]., Conclusions: Degree of fibrosis and MAGNIFI-CD index at post-treatment MRI are accurate in predicting long-term clinical closure and seem valuable in follow-up of perianal CD. A completely fibrotic tract at MRI is a robust indicator for long-term fistula closure., Eudract: 2013-002932-25 and 2018-002064-15., (© The Author(s) 2021. Published by Oxford University Press on behalf of European Crohn’s and Colitis Organisation.)

Objectives: To evaluate the effect of bowel dilation on cine-MRI small bowel motility measurements, by comparing a conventional motility score (including bowel wall and lumen) with a bowel wall-specific motility score in healthy and diseased populations., Methods: Four populations were included: 10 Crohn's patients with a stricture and prestricture dilation for segmental motility analysis, and 14 mannitol-prepared healthy subjects, 15 fasted healthy subjects and eight chronic intestinal pseudo-obstruction (CIPO) patients (characterized by dilated bowel loops) for global small bowel motility analysis. All subjects underwent a cine-MRI scan from which two motility scores were calculated: a conventional score (including bowel wall and lumen) and a bowel wall-specific score. The difference between the two scores was calculated per population and compared between groups with a one-way ANOVA and Tukey-Kramer analysis., Results: In Crohn's patients, the median (IQR) change between the conventional and wall-specific motility score was 0% (-2 to +4%) within the stricture and 0% (-1 to +7%) in the prestricture dilation. For the global small bowel, this was -1% (-5 to 0%) in mannitol-prepared healthy subjects, -2% (-6 to +2%) in fasted healthy subjects and +14% (+6 to+20%) in CIPO patients. The difference between the two motility scores in CIPO patients differed significantly from the four other groups ( p = 0.002 to p < 0.001)., Conclusions: The conventional small bowel motility score seems robust in Crohn's disease patients and healthy subjects. In patients with globally and grossly dilated bowel loops, a bowel-wall specific motility score may give a better representation of small bowel motility., Advances in Knowledge: These findings support researchers and clinicians with making informed choices for using cine-MRI motility analysis in different populations., (© 2022 The Authors. Published by the British Institute of Radiology.)

Background: Chronic intestinal pseudo-obstruction (CIPO) is a severe intestinal motility disorder of which the pathophysiology is largely unknown. This study aimed at gaining insight in fasted and fed small bowel motility in CIPO patients using cine-MRI with caloric stimulation., Methods: Eight adult patients with manometrically confirmed CIPO were prospectively included. Patients underwent a cine-MRI protocol after an overnight fast, comprising fasting-state scans and scans after ingestion of a meal (Nutridrink, 300 kcal). Small bowel motility was quantified resulting in a motility score in arbitrary units (AU) and visually assessed by three radiologists. Findings were compared with those in 16 healthy volunteers., Key Results: Motility scores (median, IQR) in CIPO patients were 0.21 (0.15-0.30) in the fasting state and 0.23 (0.15-0.27) directly postprandially. In healthy volunteers, corresponding motility scores were 0.15 (0.13-0.18) and 0.22 (0.19-0.25), respectively. The postprandial change in motility score was +1% (-19 to +21%) in CIPO and +39% (+23 to +50%) in healthy volunteers (p = 0.001*). Visual analysis revealed increased small bowel contractility in four, normal in two, and decreased in two CIPO patients., Conclusions & Inferences: Surprisingly, we found hyperactive small bowel motility in half of the CIPO patients, suggestive of uncoordinated motility. A wide variation in motility patterns was observed, both higher, lower, and comparable contractility compared with healthy subjects. No clear postprandial activation was seen in patients. Cine-MRI helps to gain insight in this complex disease and can potentially impact treatment decisions in the future., (© The Authors. Neurogastroenterology & Motility published by John Wiley & Sons Ltd.)

Background: Continuously tagged MRI during free breathing can assess bowel motility at frequencies as low as the slow wave, motility pattern range. This study aimed to evaluate noninvasive gastrointestinal-tagged MRI for small bowel motility assessment and to observe the physiological response to a 300-kcal meal challenge in healthy, overnight-fasted volunteers., Methods: After overnight fasting, 16 healthy subjects (7 women, mean age 25.5, range 19-37 years) underwent a free breathing, tagged MRI scan to capture small bowel motility. Each subject underwent a (a) baseline motility scan, (b) food challenge, (c) postchallenge scan, and (d) second postchallenge scan (after 20 minutes). Motility was quantified using a frequency analysis technique for measuring the spectral power of the strain, referred to as motility score. Motility score was assessed in 20 frequency intervals between 1 and 20 contractions per minute (cpm), and the data were analyzed with linear mixed-effect models., Key Result: The stimulation protocol demonstrated an immediate, food-induced, motility response in the low-frequency range (2-10 cpm), which is consistent with the stomach and small bowel frequency range (3-12 cpm)., Conclusions and Inferences: This study shows that this MRI tagging technique is able to quantify the fasted-to-fed response to a 300-kcal meal challenge within the specific small bowel motility frequency range in healthy subjects. The food provocation MRI protocol provides a tool to explore the gut's response to a stimulus in specific motility frequency ranges in patients with gastrointestinal dysmotility and functional disorders., (© 2019 The Authors. Neurogastroenterology & Motility published by John Wiley & Sons, Ltd.)