Appendiceal intussusception due to endometriosis presenting as acute right lower quadrant pain.

Appendiceal intussusception is a rare condition characterized by the telescoping or invagination of a portion or the entire appendix into the caecum or within the appendix itself. Diagnosing appendiceal intussusception can be challenging due to its rarity, non-specific symptoms, and lack of awareness among physicians. We present a case report of appendiceal intussusception caused by endometriosis presenting with recurrent abdominal pain in a young female that was initially missed on CT scan and laparoscopy and eventually diagnosed on CT enterography.

Multiomics reveals microbial metabolites as key actors in intestinal fibrosis in Crohn's disease.

Intestinal fibrosis is the primary cause of disability in patients with Crohn's disease (CD), yet effective therapeutic strategies are currently lacking. Here, we report a multiomics analysis of gut microbiota and fecal/blood metabolites of 278 CD patients and 28 healthy controls, identifying characteristic alterations in gut microbiota (e.g., Lachnospiraceae, Ruminococcaceae, Muribaculaceae, Saccharimonadales) and metabolites (e.g., L-aspartic acid, glutamine, ethylmethylacetic acid) in moderate-severe intestinal fibrosis. By integrating multiomics data with magnetic resonance enterography features, putative links between microbial metabolites and intestinal fibrosis-associated morphological alterations were established. These potential associations were mediated by specific combinations of amino acids (e.g., L-aspartic acid), primary bile acids, and glutamine. Finally, we provided causal evidence that L-aspartic acid aggravated intestinal fibrosis both in vitro and in vivo. Overall, we offer a biologically plausible explanation for the hypothesis that gut microbiota and its metabolites promote intestinal fibrosis in CD while also identifying potential targets for therapeutic trials.

Detecting and characterizing creeping fat in Crohn's disease: agreement between intestinal ultrasound and computed tomography enterography.

OBJECTIVES: Creeping fat (CF) is associated with stricture formation in Crohn's disease (CD). This study evaluated the feasibility of intestinal ultrasound (IUS) for semiquantitative analysis of CF and compared the agreement between IUS and computed tomography enterography (CTE). METHODS: In this retrospective study, we recruited consecutive CD patients who underwent IUS and CTE. CF wrapping angle was analyzed on the most affected bowel segment and was independently evaluated by IUS and CTE. We evaluated the wrapping angle of CF in the cross- and vertical sections of the diseased bowel. CF wrapping angle was divided into < 180° and ≥ 180°. IUS performance was assessed using CTE as a reference standard, and IUS interobserver consistency was evaluated. RESULTS: We enrolled 96 patients. CTE showed that CF wrapping angle was < 180° in 35 patients and ≥ 180° in 61 patients. We excluded three cases in which the observation positions were inconsistent between the IUS and CTE. Excellent agreement was shown between US and CTE (82/93, 88.2%). The eleven remaining cases showed inconsistencies mostly in the terminal ileum (n = 5) and small intestine (n = 4). Total agreement between IUS observers was 89.6% (86/96, κ = 0.839, p = 0.000), with perfect agreement for the ileocecal and colonic segments (35/37, 94.6% and 20/21, 95.2%, respectively) and moderate agreement for small intestinal segments (16/21, 76.2%). CONCLUSIONS: IUS could be of value and complementary to CTE for assessing CF, particularly in patients with affected terminal ileum and colon. IUS is a non-invasive technique for monitoring CD patients. CRITICAL RELEVANCE STATEMENT: In our study, excellent agreement was shown between intestinal US observers as well as between US and CT enterography (CTE) for assessing creeping fat (CF), which showed that ultrasound could be of value and complementary to CTE. KEY POINTS: Creeping fat (CF) is a potential therapeutic target in Crohn's disease. Excellent agreement was shown between US and CT Enterography (CTE) for assessing CF. Ultrasound could be complementary to CTE for assessing CF.

MR enterography radiologic ulcers in newly diagnosed ileal Crohn disease in children: frequency, inter-radiologist agreement, and clinical correlation.

BACKGROUND: Radiologic ulcers are increasingly recognized as an imaging finding of bowel wall active inflammation in Crohn disease (CD). OBJECTIVE: To determine the frequency of ulcers at MR enterography (MRE) in children with newly diagnosed ileal CD, assess agreement between radiologists, and evaluate if their presence correlates with other imaging and clinical features of intestinal active inflammation. MATERIALS AND METHODS: This retrospective study included 108 consecutive pediatric patients (ages 6-18 years) with newly diagnosed ileal CD that underwent clinical MRE prior to treatment initiation between January 2021 and December 2022. MRE examinations were independently reviewed by three pediatric radiologists who indicated the presence vs. absence of ulcers, ulcer severity (categorical depth), and ulcer extent (categorical number of ulcers). Maximum bowel wall thickness and length of disease were measured and averaged across readers. Patient demographics and clinical inflammatory markers were documented from electronic health records. Inter-radiologist agreement was assessed using Fleiss' kappa (k) statistics. Student's t-test was used to compare continuous variables. RESULTS: Mean patient age was 13.9 years (67 [62%] boys). Radiologic ulcers were recorded in 64/108 (59.3%) cases by reader 1, 70/108 (64.8%) cases by reader 2, and 49/108 (45.4%) cases by reader 3 (k = 0.36). Based on majority consensus, radiologic ulcers were present in 60/108 (55.6%) participants. Inter-radiologist agreement for ulcer severity was k = 0.23, while ulcer extent was k = 0.66. There were significant differences in C-reactive protein, erythrocyte sedimentation rate, fecal calprotectin, albumin, maximum bowel wall thickness, and length of disease between patients without and with radiologic ulcers (P < 0.05). The sensitivity and specificity of MRE for detecting endoscopic ulcers were 66.7% (95% CI, 52.1-79.2%) and 69.2% (95% CI, 48.2-85.7%), respectively. CONCLUSION: Radiologic ulcers are visible in children with newly diagnosed ileal CD, although inter-radiologist agreement is only fair. The presence of ulcers is associated with clinical laboratory inflammatory markers as well as other MRE findings of disease activity and is an additional imaging finding that can be used to evaluate intestinal inflammation.

Accelerated T2-weighted MRI of the bowel at 3T using a single-shot technique with deep learning-based image reconstruction: impact on image quality and disease detection.

RATIONALE AND OBJECTIVE: A single-shot T2-weighted deep-learning-based image reconstruction (DL-HASTE) has been recently developed allowing for shorter acquisition time than conventional half-Fourier acquisition single-shot turbo-spin echo (HASTE). The purpose of this study was to compare image quality of conventional 6 mm HASTE with DL-HASTE at 4 mm and 6 mm slice thickness. MATERIALS AND METHODS: 91 patients (51 female; mean±SD age: 44±10years) who underwent 3T MR enterography from 5/15/2023-7/15/2023 including pelvic conventional HASTE and DL-HASTE were included. Patients either had 4 mm-DL-HASTE or 6 mm-DL-HASTE. Four abdominal radiologists, blinded to sequence type, independently evaluated overall image quality, artifacts over bowel, bowel wall sharpness, and confidence for the presence/absence of bowel abnormalities on 5-point Likert scales. Readers recorded the presence/absence of ileal wall thickening, ileal inflammation, stricture, and penetrating disease on each sequence. Wilcoxon signed-rank test with continuity correction was used for paired comparisons and Wilcoxon rank sum test was used for unpaired ordinal comparisons. A p < .05 indicated statistical significance. RESULTS: Acquisition times for 6 mm HASTE, 4 mm-DL-HASTE, and 6 mm-DL-HASTE were 64 s, 51 s, and 49 s, respectively. Overall image quality and bowel sharpness were significantly improved for 4 mm-DL-HASTE versus HASTE for 3/4 readers (all p < .05) and similar for the 4th reader (p > .05). Diagnostic confidence was similar for all readers (p > .05). 6 mm-DL-HASTE was similar to HASTE for bowel sharpness, image quality, and confidence for 3/4 readers (all p > .05). The presence of ileal thickening, ileal inflammation, stricture, and penetrating disease were similar for all readers for HASTE, 4 mm-DL-HASTE, and 6 mm-DL-HASTE (all p > .05). CONCLUSION: 4 mm-DL-HASTE had superior image quality than conventional HASTE at shorter acquisition time.

Quantitative MRI in children with Crohn's disease - where do we stand?

Crohn's disease (CD) is a chronic inflammatory condition that affects the gastrointestinal tract, particularly the ileum and colon. This disease is characterized by recurrent bouts of intestinal inflammation with subsequent bowel wall damage, including scarring (i.e., fibrosis) and abnormal smooth muscle proliferation. MR enterography, an MRI examination tailored to assess the small bowel, is a first-line diagnostic tool for diagnosing CD in children, characterization and monitoring of disease severity and extent, and assessment of disease-related complications. To date, such MRI evaluations have been mostly qualitative, which can adversely impact diagnostic performance and inter-radiologist agreement. Quantitative MRI methods have been shown to aid in the evaluation of a variety of medical conditions and have been increasingly investigated in children and adults with CD. In CD, such objective techniques have been used to assist with diagnosis, assess treatment response, and characterize bowel wall histologic abnormalities. In the current work, we will review quantitative MRI methods for detecting and measuring intestinal active inflammation (MRI-based scoring systems, T1 relaxation mapping, diffusion-weighted imaging, intra-voxel incoherent motion, mesenteric phase contrast), bowel wall damage (magnetization transfer), and motility (quantitative cine imaging) in small bowel CD, with an emphasis on the pediatric population.

Early Biological Therapy Within 12 Months of Diagnosis Leads to Higher Transmural Healing Rates in Crohn's Disease.

BACKGROUND & AIMS: Transmural healing (TH) is emerging as a potential Crohn's disease (CD) treatment target. Early biological treatment seems to be associated with improved disease outcomes, but its impact on TH remains unclear. We aimed to assess the impact of early biological treatment initiation on TH and its influence on CD prognosis. METHODS: This multicenter retrospective study included adult patients with CD starting biological therapy. TH was assessed using magnetic resonance enterography (MRE) at 12 ± 6 months post-therapy initiation, with radiological examinations reviewed by blinded expert radiologists. TH was defined as complete normalization of all MRE parameters. Timing of biological therapy initiation was analyzed as a continuous variable, with optimal cutoff determined using the Youden index and clinical relevance. Logistic regression with propensity score-adjusted analysis was used to assess the association between early biological therapy initiation and TH. Long-term outcomes (bowel damage progression, CD-related surgery, CD-flare hospitalization, and therapy escalation) were evaluated. RESULTS: Among 154 patients with CD, early biological therapy initiation within 12 months of diagnosis was associated with significantly higher TH rates (adjusted odds ratio [aOR], 3.23; 95% confidence interval [CI], 1.36-7.70; P < .01), which persisted after adjusting for previous biological therapy use (aOR, 2.82; 95% CI, 1.13-7.06; P = .03). Time-to-event analysis demonstrated that TH was significantly associated with reduced time until bowel damage progression (adjusted hazard ratio [aHR], 0.28; 95% CI, 0.10-0.79; P = .02), CD-related surgery (aHR, 0.21; 95% CI, 0.05-0.88; P = .03) and therapy escalation (aHR, 0.35; 95% CI, 0.14-0.88; P = .02), independently of early biological therapy. CONCLUSIONS: Early initiation of biological therapy within 12 months of diagnosis significantly increases TH rates, leading to improved long-term outcomes in patients with CD.

Effects of oral contrast agent on the viscoelastic properties of the terminal ileum investigated using magnetic resonance elastography.

Background: While standard clinical magnetic resonance (MR) enterography can detect inflammatory bowel disease, it is of limited value in deciding between medical versus surgical treatment. Alternatively, intestinal MR elastography has the potential to contribute additional information to therapeutic decision-making; however, the influence of bowel distension by oral contrast agent on viscoelastic tissue properties remains elusive. Therefore, we aimed to investigate the influence of oral contrast agent-induced bowel distension on the viscoelastic properties of the terminal ileum in healthy volunteers. Methods: In this prospective pilot study, 20 healthy volunteers (33.2±8.2 years; 10 men, 10 women) underwent multifrequency MR elastography using a single-shot spin-echo echo planar imaging sequence at 1.5 Tesla and drive frequencies of 40, 50, 60 and 70 Hz. Maps of shear wave speed (c in ms-1) and loss angle (φ in rad), representing stiffness and viscous properties, respectively, were generated using tomoelastography data processing. The volunteers were scanned before and after ingestion of 1,000 mL of 2% mannitol solution as oral contrast agent. Results: There was no significant difference in terminal ileum biomechanical properties before vs. after ingestion of an oral contrast agent (mean c: 1.47±0.24 vs. 1.40±0.25 ms-1 with P=0.37; mean φ: 0.70±0.12 rad vs. 0.68±0.12 rad with P=0.61). Moreover, there was no statistically significant correlation between MR elastography parameters before and after the ingestion of oral contrast (c: r=0.22, P=0.36; φ: r=0.24, P=0.30). Conclusions: The results of this study suggest that bowel distension for intestinal MR elastography has no systematic effect on the biomechanical tissue properties of the terminal ileum determined by MR elastography. Therefore, future study protocols appear feasible with or without oral contrast agents.

Volumetric measurement of terminal ileal Crohn's disease by magnetic resonance enterography: a feasibility study.

OBJECTIVES: Magnetic resonance enterography (MRE) interpretation of Crohn's disease (CD) is subjective and uses 2D analysis. We evaluated the feasibility of volumetric measurement of terminal ileal CD on MRE compared to endoscopy and sMARIA, and the responsiveness of volumetric changes to biologics. METHODS: CD patients with MRE and contemporaneous CD endoscopic index of severity-scored ileocolonoscopy were included. A centreline was placed through the terminal ileum (TI) lumen defining the diseased bowel length on the T2-weighted non-fat saturated sequence, used by two radiologists to independently segment the bowel wall to measure volume (phase 1). In phase 2, we measured disease volume in patients treated with biologics, who had undergone pre- and post-treatment MRE, with treatment response classified via global physician assessment. RESULTS: Phase 1 comprised 30 patients (median age 29 (IQR 24, 34) years). Phase 2 included 12 patients (25 years (22, 38)). In phase 1, the mean of the radiologist-measured volumes was used for analysis. The median disease volume in those with endoscopically active CD was 20.9 cm3 (IQR 11.3, 44.0) compared to 5.7 cm3 (2.9, 9.8) with normal endoscopy. The mean difference in disease volume between the radiologists was 3.0 cm3 (limits of agreement -21.8, 15.9). The median disease volume of patients with active CD by sMARIA was 15.0 cm3 (8.7, 44.0) compared to 2.85 cm3 (2.6, 3.1) for those with inactive CD. Pre- and post-treatment median disease volumes were 28.5 cm3 (26.4, 31.2), 11 cm3 (4.8, 16.6), respectively in biological responders, vs 26.8 cm3 (12.3, 48.7), 40.1 cm3 (10, 56.7) in non-responders. CONCLUSION: Volumetric measurement of terminal ileal CD by MRE is feasible, related to endoscopy and sMARIA activity, and responsive to biologics. CLINICAL RELEVANCE STATEMENT: Measuring the whole volume of diseased bowel on MRE in CD is feasible, related to how biologically active the disease is when assessed by endoscopy and by existing MRE activity scores, and is sensitive to treatment response. KEY POINTS: MRE reporting for CD is subjective and uses 2D images rather than assessing the full disease volume. Volumetric measurement of CD relates to endoscopic activity and shows reduced disease volumes in treatment responders. This technique is an objective biomarker that can assess disease activity and treatment response, warranting validation.

A Fork in the Road: An Unusual Case of Duodenal-Cecal Fistula Due to a Chronic Foreign Body.

A duodenal-cecal fistula is characterized as an unnatural connection between the duodenum and cecum. Here, we present the case of a 40-year-old male with unintentional weight loss and a history of foreign body ingestion a few years prior. Computerized tomography (CT) small bowel enterography showed a linear soft tissue tract extending from the inferior aspect of the distal duodenum to the cecum. Ultimately, a diagnosis of duodenal-cecal fistula was made following esophagogastroduodenoscopy (EGD) revealing a fistula in the third part of the duodenum. A duodenal-cecal fistula secondary to foreign body ingestion is rare, with surgical intervention or endoscopic fibrin glue closure being potential treatment modalities if the fistula fails to close spontaneously. Duodenal-cecal fistulas are generally seen secondary to malignancies of the duodenum or colon, peptic ulcers, or inflammatory bowel disease. However, a duodenal-cecal fistula due to a foreign body is rare, thus highlighting the importance of keeping a broad differential, as appropriate in the clinical context.

The Spectrum of Magnetic Resonance Enterography Findings and the Role of Diffusion-Weighted Imaging in Patients with Active Crohn's Disease.

Background: The goal of this study was to evaluate magnetic resonance enterography (MRE) findings and assess the role of diffusion-weighted imaging (DWI) in patients suffering from active Crohn's disease. Methods: This retrospective study included a total number of 76 patients diagnosed with active Crohn's disease, as established by the Crohn's Disease Activity Index (CDAI). The study consisted of 30 women and 46 men, ranging in age from 13 to 72 years. All participants underwent MRE with DWI sequences. The study was conducted at Imam Khomeini hospital in Tehran between 2013 and 2018. The imaging modality utilized for the study included a 3-T SIGNA Excite MRE machine and a Siemens Magnetom 3-T magnetic resonance imaging (MRI) machine. Results: Bowel wall restriction was observed in less than half of the patients, and no significant correlation was found with extramural findings such as mesenteric edema. The study did not reveal any meaningful association between diffusion restriction and specific mural enhancement patterns, mesenteric lymphadenopathy with or without enhancement, or the length of the affected segments (P>0.05). The most common findings observed in MRI were ileum thickness in 72.4% of patients, mesenteric lymphadenopathy without enhancement in 46.1%, ileocecal thickness in 42.1%, DWI findings in 42.1%, the presence of a comb sign in 36.8%, and jejunum thickness in 30.3% of patients. Conclusion: MRE findings are useful in the evaluation of Crohn's disease activity.

Long-term outcomes and associated factors of Crohn's disease patients achieving transmural healing based on magnetic resonance enterography: a Chinese retrospective cohort study.

Background: Transmural healing (TH) has emerged as a potential treatment goal for Crohn's disease (CD). However, further research is needed to confirm its benefits and risk factors associated with TH remain unclear. Objectives: We aimed to assess the value of TH based on magnetic resonance enterography (MRE) in Chinese CD patients regarding the long-term outcomes and its associated factors. Design: Retrospective, observational cohort study. Methods: Patients with CD diagnosed by colonoscopy and MRE examination between 2015 and 2022 were included. All patients were evaluated with endoscopy together with MRE within 6-12 months after baseline and followed up for at least 6 months after evaluation. The primary endpoint was the occurrence of major outcomes during the follow-up, including drug escalation, hospitalization, and surgery. The cumulative probabilities of major outcomes were calculated using Kaplan-Meier survival curves. Logistic regression analyses were used to predict TH within 6-12 months after baseline. Results: A total of 175 patients were included in the study. Of these, 69 (39.4%) patients achieved mucosal healing (MH), but only 34 (19.4%) of them achieved TH. The median follow-up duration was 17.4 months (interquartile range, 11.6-25.5), and major outcomes occurred in 58.3% of patients. A lower occurrence rate of major outcomes was noted in patients who achieved TH than in those who achieved MH only (p = 0.012). The baseline lymphocyte/C-reactive protein ratio (LCR) [odds ratio (OR), 1.60; 95% confidence interval (CI), 1.02-2.50; p = 0.039] and bowel wall thickness (BWT) (OR, 0.72; 95% CI, 0.59-0.90; p = 0.003) were independent predictors associated with TH. According to multivariate Cox regression analysis, low LCR [hazard ratio (HR), 2.34; 95% CI, 1.51-3.64; p < 0.001], and no healing (HR, 5.45; 95% CI, 2.28-13.00; p < 0.001) were associated with an increased risk of major outcomes. Conclusion: Patients with CD who achieved TH showed improved prognosis compared to those who achieved MH only. Baseline LCR and BWT might predict TH.

Prevalence of stricturing, penetrating complications and extraintestinal manifestations in inflammatory bowel disease detected on cross-sectional imaging in a tertiary care setting.

BACKGROUND: Stricturing, penetrating complications and extraintestinal manifestations (EIMs) are frequent in patients with inflammatory bowel disease (IBD). There is limited data on the prevalence of these complications in patients with IBD. Therefore, we aimed to assess the burden of these complications detected incidentally on cross-sectional imaging. METHODS: A retrospective study conducted at two tertiary care centers in London, Ontario. Patients (≥18 years) with a confirmed diagnosis of IBD who underwent CT enterography (CTE) or MR enterography (MRE) between 1 Jan 2010 and 31 Dec 2018 were included. Categorical variables were reported as proportions and the mean and standard deviations were reported for continuous variables. RESULTS: A total of 615 imaging tests (MRE: 67.3% [414/615]) were performed in 557 IBD patients (CD: 91.4% [509/557], UC: 8.6% [48/557]). 38.2% (213/557) of patients were male, with mean age of 45.6 years (±15.8), and median disease duration of 11.0 years (±12.5). Among patients with CD, 33.2% (169/509) had strictures, with 7.8% having two or more strictures and 66.3% considered inflammatory. A fistula was reported in 10.6% (54/509), the most common being perianal fistula (27.8% [15/54]), followed by enterocutaneous fistula (16.8% [9/54]), and enteroenteric fistula (16.8% [9/54]). Additionally, 7.4% (41/557) of patients with IBD were found to have an EIM on cross-sectional imaging, with the most prevalent EIM being cholelithiasis (63.4% [26/41]), followed by sacroiliitis (24.4% [10/41]), primary sclerosing cholangitis (4.8% [2/41]) and nephrolithiasis (4.8% [2/41]). CONCLUSIONS: Approximately 40% of patients with CD undergoing cross-sectional imaging had evidence of a stricture or fistulizing disease, with 7% of patients with IBD having a detectable EIM. These results highlight the burden of disease and the need for specific therapies for these disease phenotypes.

Reporting of Magnetic Resonance Enterography in Inflammatory Bowel Disease: Results of an Italian Survey.

Background/Objectives: Inflammatory bowel diseases (IBDs) are chronic disorders that require close monitoring with imaging techniques such as magnetic resonance enterography (MRE). Standardization of radiological reports is crucial for the optimal management of IBD. We surveyed Italian radiologists regarding their experiences with MRE examinations and reporting for IBD. Methods: All members of the Italian Society of Medical and Interventional Radiology (SIRM) were invited to complete an anonymous questionnaire in April 2023. Comparison tests between variables were assessed using the χ2 test or Fisher exact test according to the least frequency group. Significance level was set for p-value < 0.05. Results: A total of 253 radiologists responded to the survey. Around 70% of the respondents declared personal clinical experience with IBD. Great agreement with the items included and described for both disease activity (i.e., intestinal wall thickness, presence of mucosal ulcers, presence of edema, mucous enhancement) and complications was reported. One-third of the respondents regularly used a structured MRE report. Centers with a high number of IBD patients per year (>1000) mostly used 3 T scanners or both 1.5 T and 3 T scanners (p < 0.001). The incorporation of scores of disease activity was associated with university and high-volume hospitals (p < 0.001). Conclusions: This survey highlighted the current routine practice and experience of MRE reports of IBD patients among Italian radiologists. We found deficiencies in the use of radiological scores in MRE reports and attendance at IBD multidisciplinary meetings.

Machine learning methods in automated detection of CT enterography findings in Crohn's disease: A feasibility study.

PURPOSE: Qualitative findings in Crohn's disease (CD) can be challenging to reliably report and quantify. We evaluated machine learning methodologies to both standardize the detection of common qualitative findings of ileal CD and determine finding spatial localization on CT enterography (CTE). MATERIALS AND METHODS: Subjects with ileal CD and a CTE from a single center retrospective study between 2016 and 2021 were included. 165 CTEs were reviewed by two fellowship-trained abdominal radiologists for the presence and spatial distribution of five qualitative CD findings: mural enhancement, mural stratification, stenosis, wall thickening, and mesenteric fat stranding. A Random Forest (RF) ensemble model using automatically extracted specialist-directed bowel features and an unbiased convolutional neural network (CNN) were developed to predict the presence of qualitative findings. Model performance was assessed using area under the curve (AUC), sensitivity, specificity, accuracy, and kappa agreement statistics. RESULTS: In 165 subjects with 29,895 individual qualitative finding assessments, agreement between radiologists for localization was good to very good (κ = 0.66 to 0.73), except for mesenteric fat stranding (κ = 0.47). RF prediction models had excellent performance, with an overall AUC, sensitivity, specificity of 0.91, 0.81 and 0.85, respectively. RF model and radiologist agreement for localization of CD findings approximated agreement between radiologists (κ = 0.67 to 0.76). Unbiased CNN models without benefit of disease knowledge had very similar performance to RF models which used specialist-defined imaging features. CONCLUSION: Machine learning techniques for CTE image analysis can identify the presence, location, and distribution of qualitative CD findings with similar performance to experienced radiologists.

Improving diagnostic confidence in low-dose dual-energy CTE with low energy level and deep learning reconstruction.

OBJECTIVE: To demonstrate the value of using 50 keV virtual monochromatic images with deep learning image reconstruction (DLIR) in low-dose dual-energy CT enterography (CTE). METHODS: In this prospective study, 114 participants (62 % M; 41.9 ± 16 years) underwent dual-energy CTE. The early-enteric phase was performed using standard-dose (noise index (NI): 8) and images were reconstructed at 70 keV and 50 keV with 40 % strength ASIR-V (ASIR-V40%). The late-enteric phase used low-dose (NI: 12) and images were reconstructed at 50 keV with ASIR-V40%, and DLIR at medium (DLIR-M) and high strength (DLIR-H). Image standard deviation (SD), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), edge-rise-slope (ERS) were computed. The quantitative comb sign score was calculated for the 27 patients with Crohn's disease. The subjective noise, image contrast, display of rectus artery were scored using a 5-point scale by two radiologists blindly. RESULTS: Effective dose was reduced by 50 % (P < 0.001) in the late-enteric phase to 3.26 mSv. The lower-dose 50 keV-DLIR-H images (SD:17.7 ± 0.5HU) had similar image noise (P = 0.97) as the standard-dose 70 keV-ASIR-V40% images (SD:17.7 ± 0.73HU), but with higher (P < 0.001) SNR, CNR, ERS and quantitative comb sign score (5.7 ± 0.17, 1.8 ± 0.12, 156.04 ± 5.21 and 5.05 ± 0.73, respectively). Furthermore, the lower-dose 50 keV-DLIR-H images obtained the highest score in the rectus artery visibility (4.27 ± 0.6). CONCLUSIONS: The 50 keV images in dual-energy CTE with DLIR provides high-quality images, with a 50 % reduction in radiation dose. Images with high contrast and density resolutions significantly enhance the diagnostic confidence of Crohn's disease and are essential for the clinical development of individualized treatment plans.

Comparative Assessment of Crohn's Disease Activity Using Magnetic Resonance Enterography and Endoscopy.

Introduction Magnetic resonance enterography (MRE) has emerged as a promising technique for evaluating the extent and severity of Crohn's disease activity. To compare how we measure Crohn's disease activity with MRE and endoscopy. Material and methods We retrospectively reviewed MRE studies of 60 patients with suspicious Crohn's disease who underwent 1.5-T MRI examinations (T1-weighted images pre- and post-IV contrast medium administration and T2-weighted images) and endoscopy within one month, and they were evaluated by one radiology consultant with experience of 17 years. Endoscopy was used as the reference standard for diagnosing active Crohn's disease cases. Data analysis was performed using the websites (www.graphpad.com and www.medcalc.org) and Microsoft Excel (Microsoft® Corp., Redmond, USA). Results A total of 35 patients were included in the study. The remaining 25 patients were excluded either due to non-available data in the endoscopy report or cases of non-Crohn's disease. The MRI examinations were reviewed by one radiology consultant and revealed 27 active and eight non-active Crohn's disease cases compared to 30 active and five non-active Crohn's disease cases in endoscopy. The sensitivity of MRI in detecting active cases of Crohn's disease compared to endoscopy was 83.3% and the specificity of 60%. The strength of agreement between both methods was fair to good (Kappa = 0.347, p-value = 0.4497, Chi-squared = 0.571 with one degree of freedom). Conclusion MRE statistically has a good impact on the assessment of Crohn's disease as well as endoscopy with the parameters used in this study. Non-invasiveness and the changes of activity seen in the bowel proximal to the ileocecal junction undetectable by endoscopy make MRE more practically applicable in this aspect.

MRI radiomics enhances radiologists' ability for characterizing intestinal fibrosis in patients with Crohn's disease.

OBJECTIVES: We aimed to develop MRI-based radiomic models (RMs) to improve the diagnostic accuracy of radiologists in characterizing intestinal fibrosis in patients with Crohn's disease (CD). METHODS: This retrospective study included patients with refractory CD who underwent MR before surgery from November 2013 to September 2021. Resected bowel segments were histologically classified as none-mild or moderate-severe fibrosis. RMs based on different MR sequence combinations (RM1: T2WI and enhanced-T1WI; RM2: T2WI, enhanced-T1WI, diffusion-weighted imaging [DWI], and apparent diffusion coefficient [ADC]); RM3: T2WI, enhanced-T1WI, DWI, ADC, and magnetization transfer MRI [MTI]), were developed and validated in an independent test cohort. The RMs' diagnostic performance was compared to that of visual interpretation using identical sequences and a clinical model. RESULTS: The final population included 123 patients (81 men, 42 women; mean age: 30.26 ± 7.98 years; training cohort, n = 93; test cohort, n = 30). The area under the receiver operating characteristic curve (AUC) of RM1, RM2, and RM3 was 0.86 (p = 0.001), 0.88 (p = 0.001), and 0.93 (p = 0.02), respectively. The decision curve analysis confirmed a progressive improvement in the diagnostic performance of three RMs with the addition of more specific sequences. All RMs performance surpassed the visual interpretation based on the same MR sequences (visual model 1, AUC = 0.65, p = 0.56; visual model 2, AUC = 0.63, p = 0.04; visual model 3, AUC = 0.77, p = 0.002), as well as the clinical model composed of C-reactive protein and erythrocyte sedimentation rate (AUC = 0.60, p = 0.13). CONCLUSIONS: The RMs, utilizing various combinations of conventional, DWI and MTI sequences, significantly enhance radiologists' ability to accurately characterize intestinal fibrosis in patients with CD. CRITICAL RELEVANCE STATEMENT: The utilization of MRI-based RMs significantly enhances the diagnostic accuracy of radiologists in characterizing intestinal fibrosis. KEY POINTS: MRI-based RMs can characterize CD intestinal fibrosis using conventional, diffusion, and MTI sequences. The RMs achieved AUCs of 0.86-0.93 for assessing fibrosis grade. MRI-radiomics outperformed visual interpretation for grading CD intestinal fibrosis.

Diagnostic value of MR and CT enterography in post-operative recurrence of Crohn's disease: a systematic review and meta-analysis.

Post-operative recurrence is a critical issue in the surveillance of Crohn's disease after ileocecal resection. This meta-analysis aims to assess the diagnostic yield of enterography techniques in post-operative recurrence of Crohn's disease. A systematic electronic bibliographic databases search was conducted. The inclusion criteria of original articles were: Utilized MR enterography or CT enterography after ileocolonic resection; Documented recurrence by ileo-colonoscopy (Rutgeerts' score ≥ i2); Provided crude data of diagnostic performance. A random-effect method was used for analysis. Relative risk and diagnostic value of each imaging feature were calculated. Eleven studies (11 populations and 589 patients) were included (4 CTE and 7 MRE with 248 and 341 patients, respectively). The pooled sensitivity and specificity of the enterography were 91% (95% CI: 0.85-0.95) and 75% (95% CI: 0.56-0.87), respectively. The pooled sensitivity and specificity of CTE were 93% (95% CI: 0.87-0.96) and 67% (95% CI: 0.35-0.90), respectively. MRE revealed pooled sensitivity and specificity of 90% (95% CI: 0.78-0.96) and 78% (95% CI: 0.57-0.90), respectively. The inter-study heterogeneity was low for sensitivity (I2 = 29%, p-value = 0.17) and high for specificity (I2 = 85%, p-value < 0.01). Wall enhancement, anastomosis wall thickening, anastomosis stenosis, pre-anastomotic dilatation, penetrating lesion, comb sign, and perivisceral edema were significantly higher in POR patients. Wall thickening and penetrating lesion were the most sensitive (81%) and specific (97%) findings, respectively. MRE and CTE exhibit high sensitivity and acceptable specificity (especially MRE) for detection of recurrence in Crohn's disease which makes them an effective initial screening tool and reserves ileo-colonoscopy for those patients with inconclusive enterography results.