Intestinal ultrasound (IUS) is increasingly used for real-time assessment of inflammatory bowel disease (IBD) but quantitative analysis with artificial intelligence (AI) remains limited to bowel wall thickness (BWT) and single-frame segmentation, failing to exploit the temporal information in cineloops (CLs). The aim here was to evaluate the accuracy of an AI model compared to expert central readers using IUS CLs. We developed a novel model using a semi-supervised algorithm combined with a temporal module, trained on 680,000 IUS images from 1572 CLs (327 patients from multiple centres). 1205 frames from 403 CLs on 94 patients were labelled by 8 domain experts (203 validation, 1002 training images). The CLs had various segments per patient with active IBD, and included axial, longitudinal and oblique sections. An external test set (27 patients, 58 CLs) of active Crohn’s patients (ascending, transverse, descending colon), centrally read by 3 expert readers, was used for initial evaluation. The model was optimized to segment 9 categories including bowel wall (BW), psoas, iliac vessels (IV), and inflamed mesentery (IM). Each output was based on a current frame and context representations from previous frames. The model continuously segments and tracks anatomy, generating temporally coherent delineations and data that feed intra- and inter-frame measurement algorithms. On the validation set, we calculated the Dice similarity coefficient (DSC), an overlap-based metric, from the expert annotations. Intraclass correlation coefficient (ICC) scores from ground truth measurements were made for every labelled image. Qualitative evaluation by domain experts confirmed consistency and anatomical precision of the outputs across a range of bowel regions and disease activity. Quantitatively, on the validation set our model achieved DSC of 0.73 [0.70 - 0.75], 0.26 [0.23 - 0.28], 0.62 [0.55 - 0.68], 0.63 [0.53 - 0.72], 0.72 [0.64 - 0.79] and 0.41 [0.32 - 0.49] for BW, peritoneal lining, rectus, psoas, IV and IM. Based on BW segmentations, the measurement algorithm achieved an ICC of 0.83 [0.77 - 0.87] between predictions and per frame expert measurements. On the external test dataset, the ICC between an aggregated AI-driven measurement per CL and the mean of all reader measurements was 0.83 [0.73 - 0.9]. Unlike prior approaches focused on static frames or derived BWT estimation, this method preserves frame-to-frame continuity, enabling reproducible analysis of CLs with no manual pre-selection of measurement areas. Our model provides identification of many anatomical structures in addition to BWT, essential to moving AI beyond this measure and towards fully automated disease activity monitoring. Conflict of interest: Novak, Kerri L.: Research Grants: Helmsley Trust, Pfizer, Janssen Adboard, consulting fees: Abbvie, Janssen, Pfizer, Pendopharm, Takeda, Elli Lilly, Celltrion, Bristal Myers Non financial support (ultrasound machine) McKesson Pharmcy. Pfizer, Celltrion Mendel, Robert: No conflict of interest Dolinger, Michael: Personal Fees: Michael Dolinger is a consultant for Neruologica., a subsidiary of Samsung Electronics Co., Ltd. Maaser, Christian: Speaker honaria and/or Advisory honaria Abbvie, Alfasigma, Biogen, Falk Foundation, Galapagos, Gilead, J & J, MSD Sharp & Dome, Pfizer, Roche, Samsung, Takeda Gecse, Krisztina B.: Grant: Abbvie, Pfizer Inc, Celltrion and Galapagos/Alfasigma Personal Fees: Consultancy fees from AbbVie, ​Galapagos, Gilead, Immunic Therapeutics, Janssen Pharmaceuticals, Pfizer Inc., and Takeda and speaker’s honoraria from Celltrion, Eli Lilly, Janssen Pharmaceuticals, Pfizer Inc. and Takeda. Nash, Carla: No conflict of interest Smyth, Matthew: No conflict of interest Sagami, Shintaro: Shintaro Sagami has served as an advisory board member, consultant, or speaker for AbbVie, Alimentiv, Bristol Myers Squibb, Celltrion, EA Pharma, Eli Lilly, Ferring Pharmaceuticals, Gilead Sciences, Janssen Pharmaceuticals, Kyorin Pharmaceutical, Mitsubishi Tanabe Pharma, Mochida Pharmaceutical, Nippon Kayaku, Pfizer, Takeda, and Zeria Pharmaceutical, and has received research funding from Bristol Myers Squibb, EA Pharma, Gilead Sciences, Helmsley Charitable Trust, JIMRO, Kyorin Pharmaceutical, Miyarisan, Mochida Pharmaceutical, Nippon Kayaku, Pfizer, Sekisui Medical, Samsung, Takeda, and Zeria Pharmaceutical. Nylund, Kim: Other: PI in clinical trial (Takeda) Ellis, Edward: No conflict of interest Sanghera, Daljinder: No conflict of interest Dr. Flegg, Daniel: No conflict of interest Torisu, Misaki: No conflict of interest Fu, Y. Nancy: No conflict of interest Ernest-Suárez, Kenneth: Consulting/Advisory Board fees: Abbvie, AstraZeneca, Johnson & Johnson, Pfizer, Ferring, Sandoz, SatisfAI, Takeda Johannessen, Solveig: No conflict of interest Gurm, Sunny: No conflict of interest Panaccione, Remo: No conflict of interest Wilkens, Rune Levring: Personal Fees: Janssen, Takeda Denmark, AbbVie, Pfizer Denmark, Alimentiv Byrne, Michael: Founder and shareholder, Dova Health Intelligence

According to the most recent guidelines, uncomplicated acute appendicitis could be treated conservatively using broad-spectrum antibiotics, but if radiological signs of appendix rupture are present, appendectomy should be considered as first-line treatment. There is limited evidence in literature regarding the non-operative management of complicated acute appendicitis, particularly in the subset of patients with Crohn's disease. Intestinal and contrast-enhanced ultrasound appear pivotal to both diagnosing complications and promptly identifying the non-responding patients. We describe two cases of complicated acute appendicitis, successfully treated with broad-spectrum antibiotic therapy and tight monitoring with both intestinal and contrast-enhanced ultrasound, in patients with Crohn's disease.

AIM:Patients with diarrhea-predominant irritable bowel syndrome (IBS-D) who present with symptom exacerbation [defined by a high IBS-Symptom Severity Scale (IBS-SSS)] may have increased fecal calprotectin (FC). Intestinal ultrasound (IUS) is used to measure bowel wall thickness (BWT). The aim of our study was to measure BWT in IBS-D patients, ulcerative colitis (UC) and healthy controls (HC), and compare BWT, IBS-SSS score, and FC level. MATERIAL AND METHOD:Patients with IBS-D and symptom exacerbation (n=100), active UC (n=25), and HC (n=30) were included. FC was measured in all groups. IBS-D patients with an IBS-SSS score >75 and FC level >50 µg/g underwent IUS and colonoscopy. RESULTS:Patients with IBS-D had a (mean±SEM) IBS-SSS score of 268±11, FC level of 260±46 µg/g, and a normal colonoscopy. IUS showed a significant difference (p<0.0001) between sigmoid BWT for IBS-D (3.16±0.09 mm) and HC (1.6±0.12 mm). Color Doppler signals were also absent. A significant correlation between sigmoid BWT and FC level (r=0.48, p=0.0012) was found in patients with IBS-D. CONCLUSION:Compared to HC, sigmoid BWT was significantly increased in IBS-D patients with symptom exacerbation. Sigmoid BWT correlates significantly with FC levels during IBS-D symptom exacerbation.

Purpose:Gastrointestinal ultrasound is a well-established method for diagnosing and monitoring Crohn's disease (CD). The aim of this study was to investigate whether wall layer data measured on gastrointestinal ultrasound could predict endoscopic activity in CD. Materials and Methods:64 CD patients underwent a gastrointestinal ultrasound examination and endoscopy ± 2 weeks apart in a single-center prospective study. Bowel wall thickness and the thickness of individual wall layers corresponding to the mucosa, submucosa and the proper muscle wall were measured and compared with the simple endoscopic score of Crohn's disease (SES-CD) in the most affected bowel segment where SES-CD >2 was defined as activity. Results:There was increased absolute thickness of the mucosa (1.8 versus 1.1mm, p =0.001), submucosa (2.8 versus 1.2mm, p <0.001), and proper muscle (1.6 versus 1.1mm, p =0.006) in patients with endoscopic activity. After an ROC analysis, Youden's index suggested a 1.8 mm cut-off for submucosal thickness and disease activity resulting in a sensitivity of 90%, specificity of 78.3%, and accuracy of 84.9%. In contrast, a bowel wall thickness of 3 mm had a sensitivity of 97.3%, specificity of 52.0%, and accuracy of 79.0%. The submucosa was also relatively thicker (0.45 versus 0.36, p=0.008), while the proper muscle was relatively thinner (0.25 versus 0.34, p=0.001) in endoscopic activity. Conclusion:Patients with Crohn's disease and endoscopic activity had an increased thickness of all bowel wall layers in affected areas. Measurements of the submucosa may be used to assess disease activity with results similar to bowel wall thickness.

BACKGROUND AND AIMS:At Haukeland University Hospital, the Mobile Health Index for Ulcerative Colitis (MHI-UC), a patient-reported outcome measure (PROM), is used in the outpatient clinic to detect disease activity in patients. The primary objective of the study was to compare the MHI-UC with the endoscopic Mayo score (e-MAYO) in a Norwegian cohort, and to investigate the impact on treatment decisions and response. MATERIALS AND METHODS:The study is single-center and retrospective. Patients were identified by searching patient journals and screened for participation. Patients who had answered the MHI-UC within ±4 weeks of endoscopy, with no change in treatment, were eligible. Clinical intervention involved treatment changes or referrals to endoscopy or cross-sectional imaging. For those with multiple endoscopies, data from all were collected. Response was defined as a change in e-MAYO score of 1 or more. RESULTS:The MHI-UC correlated with endoscopic activity scored by e-MAYO (r = 0.64, p < 0.001). The AUROC for detecting endoscopic disease activity was 0.92 for e-MAYO > 1 and 0.78 for e-MAYO > 0. Patients receiving a clinical intervention (4.3 ± 3.5 vs 2.3 ± 2.7, p = 0.001) or with a change in e-MAYO (3.9 ± 2.7 points vs 0.7 ± 2.8 points) had a significantly higher MHI-UC compared to those without need for intervention. CONCLUSIONS:The MHI-UC corresponds well with the endoscopic evaluation in patients with UC. The MHI-UC can be used to detect moderate to severe disease activity in UC with high accuracy and to detect changes in endoscopic activity.

Purpose This study aimed to assess the feasibility of dynamic contrast-enhanced ultrasound with Sonazoid, its correlation with disease activity, its ability to differentiate between remission/mild activity and moderate/severe activity, and if a region of interest including the mucosa and submucosa was different compared to one encompassing the entire wall. Materials and methods We prospectively studied 48 patients with Crohn's disease who underwent colonoscopy and dynamic contrast-enhanced ultrasound with Sonazoid from 2015 to 2019. We compared the local simple endoscopic score for Crohn's disease in the most affected area with parameters from Vuebox, including peak enhancement, wash-in and wash-out area under the curves, wash-in and wash-out rates, and wash-in perfusion index. Region of interest-1 (ROI-1) included all wall layers, and region of interest-2 (ROI-2) included the mucosa and submucosa. Linear data and normalised data were used. Technical failure or a quality of fit value of<80% was considered a failed examination. Results The feasibility of the dynamic contrast-enhanced ultrasound examination was 73%. No significant findings were noted in the linear data ( p >0.05). In the normalised data in both ROI-1 and ROI-2, the local simple endoscopic score for Crohn's disease correlated significantly with peak enhancement ( r =0.38 and r =0.35), wash-in rate ( r =0.34 and r =0.34), and wash-in perfusion index ( r =0.40 and r =0.37) and with wash-in area under the curve ( r =0.36) in ROI-2. In patients with moderate/severe disease peak enhancement, wash-in area under the curve, wash-out area under the curve, wash-in rate, and wash-in perfusion index were significantly higher in both region of interests ( p <0.05). All parameters were significantly different in ROI-1 and ROI-2 ( p <0.05). Conclusions Dynamic contrast-enhanced ultrasound parameters can differentiate between remission/mild and moderate/severe activity in Crohn's disease, but the method has relatively low feasibility.

Abstract Background Gastrointestinal ultrasound (GIUS) is a method with both high sensitivity and specificity for evaluating disease activity in patients with Crohn’s disease. However, detecting and classifying stenosis and ulcerations can be challenging with GIUS. Developing an ultrasound method for detecting and categorising these findings would be of significant benefit to these patients. GIUS using an oral ultrasound contrast agent containing microbubbles is a new method with the potential to improve the intestinal ultrasound examination in patients with Crohn’s disease. The goal of this study is to investigate if intestinal ultrasound with oral contrast containing Sonazoid microbubbles in a PEG solution is a feasible and safe method in patients with Crohn’s disease. Methods 24 patients with Crohn’s disease in the terminal ileum (TI) was examined with ileocolonoscopy and intestinal ultrasound with oral contrast in a phase 2, single centre prospective cross-sectional drug trial. The ultrasound examination was done using Logiq E10 in contrast hybrid mode after ingestion of 1ml Sonazoid mixed with 500ml of PEG. The quality of the examination was graded 0-3 based on the amount of contrast in the lumen. In grade 3 the terminal ileum filled completely with contrast, and this was considered a successful examination. The contrast grade and transit time to TI after ingestion was documented along with symptoms, side effects and disease activity using "Mobile Health Index for Crohn’s Disease" before and after the study visit (1). Results All the included patients completed the ultrasound examination. The examination had a feasibility of 96 % as 23/24 patients achieved contrast effect grade 3 in TI with a clear separation of the intestinal wall and lumen. Average time from ingestion to grade 3 contrast effect in the TI was 20.8 min. Average duration of contrast effect grade 3 in the TI was 50.4 min. 50% of the patients had self-limiting diarrhea after the examination, however using paired samples T test there was no significant difference in average disease activity measured by MHICD before and after the examination (p=0.685). 96% of the patients agreed or completely agreed to undergo the examination again. Conclusion All except one patient achieved successful grade 3 contrast effect in the terminal ileum with a clear separation of the lumen and intestinal wall. Half of the patients had self-limiting diarrhea, but there was no increase in Crohn’s disease activity after the contrast examination. According to our study, ultrasound with oral contrast consisting of 1ml Sonazoid and 500ml PEG is a feasible and safe method to examine patients with Crohn’s disease. References 1. Van Deen WK et. Al. Development and Validation of an Inflammatory Bowel Diseases Monitoring Index for Use With Mobile Health Technologies. Clin Gastroenterol Hepatol. 2016 Dec;14(12):1742-1750.e7. doi: 10.1016/j.cgh.2015.10.035.

Abstract Background First line medical treatment in acute severe ulcerative colitis (ASUC) is intravenous corticosteroids. Patients with insufficient response receives rescue treatment. The decision is made by the treating physician and is based on disease severity and improvement in stool frequency, rectal bleeding, biochemical parameters, and general well-being. Gastrointestinal ultrasound (GIUS) can be used to find the degree of inflammation in ulcerative colitis, but can it be used to detect the lack of treatment response in ASUC? Methods Patients with ASUC were included from June 2020 to Nov 2024 at two hospitals in Bergen, Norway. They were examined with GIUS prior to treatment with iv corticosteroids and after 2-3 days of treatment. Patients with a normal GIUS, endoscopic MAYO<2 or isolated proctitis were excluded. Bowel wall thickness, bowel wall vessel density with colour Doppler, loss of haustration and fatty tissue reaction was registered for every segment of the colon as well as an activity score based on these parameters1. The two main outcomes of the study were the clinical decision to give rescue with infliximab and Lindgren’s criteria for the risk of colectomy2. Results In total 33/64 patients received rescue treatment. In the sigmoid colon the wall was 4.3±1,3 mm in patients receiving rescue treatment and 2.5±1mm in the others (p<0.001). There was also a significant difference in vessel density, haustrations, and fatty tissue reaction. Furthermore, there were significant differences for wall thickness in all the other colon segments including the sum of these measurements. The full score based on all parameters was 15.2±5,2 vs 8.3±5,3 (p<0.001). The areas under the receiver operating curve (AUROC) for wall thickness in the sigmoid colon, total bowel wall thickness and the activity score were 0.87 (0.79-0.96), 0.84 (0.75-0.94) and 0.84 (0.74-0.94), respectively. According to Lindgren’s Criteria 23/64 had a high risk for colectomy. AUROCs for the same parameters were 0.86(0.75-0.96), 0.88(0.80-0.97) and 0.85 (0.76-0.94), respectively. If a low risk of colectomy is required a total bowel wall thickness ≥ 9mm at day 2-3 predicts the risk of colectomy with 100% sensitivity and 50% specificity. For the single measurement in the sigmoid colon and a corresponding sensitivity of 96% (cut off 2.4 mm) the specificity will wall fall to 32.5%. Conclusion GIUS can be used to detect insufficient treatment response in ASUC already after 2-3 days of intravenous corticosteroids which confirms previous findings3. A single measurement in the sigmoid colon could be sufficient, but the combined sum of bowel wall thickness in all colon segments could be better for selecting patients that should get rescue treatment. References 1.Bots S, Nylund K, Lowenberg M, Gecse K, D'Haens G. Intestinal Ultrasound to Assess Disease Activity in Ulcerative Colitis: Development of a novel UC-Ultrasound Index. J Crohns Colitis. Aug 2 2021;15(8):1264-1271. doi:10.1093/ecco-jcc/jjab002 2.Lindgren SC, Flood LM, Kilander AF, Lofberg R, Persson TB, Sjodahl RI. Early predictors of glucocorticosteroid treatment failure in severe and moderately severe attacks of ulcerative colitis. Eur J Gastroenterol Hepatol. Oct 1998;10(10):831-5. doi:10.1097/00042737-199810000-00003 3.Ilvemark J, Wilkens R, Thielsen P, et al. Early Intestinal Ultrasound Predicts Intravenous Corticosteroid Response in Hospitalised Patients With Severe Ulcerative Colitis. J Crohns Colitis. Nov 23 2022;16(11):1725-1734. doi:10.1093/ecco-jcc/jjac083

Abstract Background Crohn's disease (CD) often leads to the development of intestinal strictures, requiring effective differentiation between inflammatory and fibrotic for the optimal treatment strategies. Despite recent advances in drug development targeting fibrosis, current evaluation methods remain insufficient. Contrast-enhanced ultrasound (CEUS) is a promising modality for assessing vascularity and inflammation, yet its accuracy in fibrosis detection needs more validation. Methods A systematic review and meta-analysis were conducted using IPD to determine the diagnostic accuracy of CEUS in identifying intestinal fibrosis in CD. Our search included databases such as MEDLINE, EMBASE, and Web of Science up until March 23, 2023. Inclusion criteria required a confirmed diagnosis of CD and studies that evaluated the accuracy of CEUS parameters, including total area under the curve (AUC), wash-in AUC, wash-out AUC, peak enhancement, wash-in perfusion index, wash-in rate, wash-out rate, rise time, fall time, and mean transit time related to fibrosis in CD (Figure 1 (A)). The quality of included studies was assessed using the QUADAS-2 tool, with each study mandatorily using surgical specimen pathology as a reference standard in at least one instance. Results Our qualitative synthesis included eight studies encompassing 306 patients. These studies were generally assessed to have a high risk of bias. It is important to note that while peak enhancement and AUC were frequently examined across studies, neither parameter had established absolute cutoff values for the diagnosis of fibrosis. From the three studies where IPD was available, detailed data from 80 patients were included in the meta-analysis (colon n=11 and small bowel n= 69). Among them, 54 underwent surgical intervention with fibrosis being confirmed in 31. The highest diagnostic accuracy was observed for total AUC and wash-in AUC, with pooled sensitivity and specificity for predicting fibrosis at 0.86 (95% CI, 0.59–0.97) and 0.25 (95% CI, 0.03–0.76), respectively (Figure 1 (B)). Conclusion This meta-analysis with IPD pioneers the exclusive evaluation of CEUS for fibrotic strictures in CD. It reveals a significant risk of bias in the primary research and a notable absence of consensus on the CEUS parameters' threshold values for distinguishing fibrosis from inflammation. The observed low specificity highlights the need for innovative strategies in future research, such as integrating CEUS with techniques like elastography, to enhance the precision of fibrosis detection in CD. PROSPERO 2020 CRD42020214472. https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020214472

The widespread use of portable ultrasound scanners has promoted the concept of point of care ultrasound (POCUS), namely “ultrasound performed bedside and interpreted directly by the clinician.” The purpose of this short review is to outline how POCUS can be used in patients with diseases of the gastrointestinal (GI) tract. POCUS is not a replacement for comprehensive ultrasound, but rather allows physicians immediate access to clinical imaging for rapid diagnosis and efficient work-up and treatment of the patients. There are many indications for doing POCUS of the GI tract, including abdominal pain, diarrhea, palpable masses, and to detect fluid or free air in the abdominal cavity. To improve the visibility of deeper parts of the abdomen, the graded compression technique with the scan head is useful. During POCUS, the operator should look for signs of severe pathology including target lesions, the pseudo-kidney sign, the onion sign, dilated bowel loops, gastric retention, free fluid, and free air, depending on the actual clinical problem. We conclude that POCUS of the GI tract is very useful to provide a rapid diagnosis in many clinical scenarios.

Purpose Gastrointestinal ultrasound (GIUS) is a noninvasive imaging technique that may be used to study physiological changes in the small bowel. The aim of the study was to investigate the feasibility of measuring blood flow (BF) in the superior mesenteric artery (SMA) and regional motility in the small bowel with GIUS before and after a test meal and to compare ultrasound parameters to demographic factors such as age, sex, height, weight, and smoking habits. Materials and Methods 122 healthy volunteers aged 20 to 80 were examined after an overnight fast. Small bowel motility was registered in the upper left and lower right quadrants (ULQ and LRQ) with TUS and BF in the SMA with pulsed wave Doppler. The first 23 volunteers also received a 300 Kcal test meal and were re-examined 30 min postprandial. Results The feasibility of measuring BF was 97% in fasting patients while motility could be detected in 52% and 62% in the ULQ and LRQ, respectively. Females had a lower resistive index (RI) and a higher mean velocity than males, while the overall BF correlated with height. The RI had a negative correlation with age. Healthy volunteers with motility in the ileum were on average younger than those without motility. After the test meal, motility could be detected in the ULQ and LRQ in 95% and 90%, respectively, and the mean number of contractions in the ULQ increased significantly. As expected, there was a clear increase in all BF-parameters postprandially. Conclusion Regional motility in the small bowel was easier to detect after a test meal. There were some associations between demographic parameters and ultrasound parameters but overall the effects were relatively small.

Abstract Background In the assessment of treatment response in Crohn’s Disease (CD) objective measures are superior to clinical improvement. Intestinal ultrasound (IUS) is an emerging modality with high accuracy to detect CD disease activity. Less is known about early transmural changes at IUS in treatment follow-up. Therefore, we aimed to investigate conventional IUS and contrast-enhanced ultrasound (CEUS) parameters and how they are associated with endoscopic treatment response. Methods In this longitudinal prospective cohort study, consecutive patients with active CD according to the simplified endoscopic score (SES-CD≥3) starting anti-TNF-α treatment were included. We recorded clinical, biochemical, IUS and CEUS parameters at baseline (T0), after 4–8 weeks (T1) and at 12–34 weeks (T2). IUS parameters were scored as previously established1. The SES-CD was scored per segment by a gastroenterologist immediately after endoscopy. The bowel segment with highest SES-CD score and thickest wall on IUS was identified. At T2, endoscopic response (decrease SES-CD≥50%) and endoscopic remission (SES-CD=0) were scored per segment. IUS and CEUS were scored blindly by two readers using recorded videos. Results 40 patients were included (Table 1) with 23 completing follow-up. The other 17 patients had side-effects and stopped treatment (n=9), underwent bowel surgery (n=5) or were lost to follow-up (n=3). At T2, 14 reached endoscopic remission, 17 had endoscopic response. The absolute decrease in BWT at T1 and T2 paralleled endoscopic response (Figure 1). Decrease in BWT of 18% at T1 (Fig 2) predicted endoscopic response accurately (OR: 10.8, 95%CI: 1.7–69.0, p=0.012). For T2, 29% decrease in BWT (Fig 2) was most accurate to determine endoscopic response (OR: 37.5, 95%CI: 2.8–507.5, p=0.006). At T2, a BWT of 3.2 mm was most accurate (AUROC: 0.940, 95%CI: 0.862–1.000, p<0.0001, sensitivity: 92%, specificity: 85%) to determine endoscopic remission (OR: 39.4, 95%CI: 7.7–202.6, p<0.0001). Normalization of Colour Doppler Signal (CDS) (no signal or single vessel) (OR: 13.8, 95%CI: 1.3–147.8, p=0.03) or Wash-out Rate (WoR) at CEUS (1 dB increase: OR: 0.8, 95%CI: 0.60–0.96, p=0.019) added significantly to BWT to determine endoscopic remission at T2. Conclusion Decrease of BWT 4–8 weeks after treatment initiation predicted endoscopic response later during follow-up. In addition, we have provided accurate cut-off values for (Δ)BWT associated with endoscopic response and remission at different time-points. CDS or WoR were both of additional value to determine endoscopic remission after 12–34 weeks. As CEUS is time consuming, CDS might be sufficient in the close follow-up of CD patients. Reference 1. Novak et al, JCC 2021

BACKGROUND AND AIMS:No consensus exists on defining intestinal ultrasound response, transmural healing, or transmural remission in inflammatory bowel disease, nor clear guidance for optimal timing of assessment during treatment. This systematic review and expert consensus study aimed to define such recommendations, along with key parameters included in response reporting. METHODS:Electronic databases were searched from inception to July 26, 2021, using pre-defined terms. Studies were eligible if at least two intestinal ultrasound [IUS] assessments at different time points during treatment were reported, along with an appropriate reference standard. The QUADAS-2 tool was used to examine study-level risk of bias. An international panel of experts [n = 18] rated an initial 196 statements [RAND/UCLA process, scale 1-9]. Two videoconferences were conducted, resulting in additional ratings of 149 and 13 statements, respectively. RESULTS:Out of 5826 records, 31 full-text articles, 16 abstracts, and one research letter were included; 83% [40/48] of included studies showed a low concern of applicability, and 96% [46/48] had a high risk of bias. A consensus was reached on 41 statements, with clear definitions of IUS treatment response, transmural healing, transmural remission, timing of assessment, and general considerations when using intestinal ultrasound in inflammatory bowel disease. CONCLUSIONS:Response criteria and time points of response assessment varied between studies, complicating direct comparison of parameter changes and their relation to treatment outcomes. To ensure a unified approach in routine care and clinical trials, we provide recommendations and definitions for key parameters for intestinal ultrasound response, to incorporate into future prospective studies.

Purpose To explore the ability of gastrointestinal ultrasound (GIUS) to separate patients in endoscopic remission from patients with active disease in a heterogeneous hospital cohort with Crohn's disease (CD). Materials and Methods 145 CD patients scheduled for ileocolonoscopy were prospectively included. The endoscopic disease activity was quantified using the Simple Endoscopic Score for Crohn's disease (SES-CD), and mucosal healing was strictly defined as SES-CD = 0. Ultrasound remission was defined as wall thickness < 3 mm (< 4 mm in the rectum). Additionally, SES-CD was compared to color Doppler, Harvey Bradshaw's index (HBI), C-reactive protein (CRP) and calprotectin. 23 patients were examined by two investigators for interobserver assessment. Results 102 had active disease and 43 patients were in remission. GIUS yielded a sensitivity of 92.2 % and a specificity of 86 % for wall thickness and a sensitivity of 66.7 % and a specificity of 97.7 % for color Doppler. The sensitivity and specificity were 34.3 % and 88.4 %, respectively, for HBI, 35.7 % and 82.9 %, respectively, for CRP and 55.9 % and 82.1 %, respectively, for calprotectin. The interobserver analysis revealed excellent agreement for wall thickness (k = 0.90) and color Doppler (k = 0.91) measurements. Conclusion GIUS has a high sensitivity for detecting endoscopic activity. Accordingly, bowel ultrasound has the potential to reduce the number of routine ileocolonoscopies in patients with CD.

Abstract Background Gastrointestinal ultrasound (GIUS) can be used to measure bowel wall thickness (BWT). If the bowel wall is less than 3 mm in all bowel segments in a patient with Crohn’s disease(CD) this predicts endoscopic remission with a high degree of accuracy, but still some CD patients with disease located to the terminal ileum and colon will have a thickened bowel wall even if they are in endoscopic remission. Could BWT be an independent predictor of disease activity in CD? The aim of the study was to investigate if a normalisation of bowel wall thickness in CD patients affects risk for important negative clinical endpoints such as need for corticosteroids, failure in maintenance treatment, hospital admissions and surgery. Methods Patients with CD referred to the Haukeland University Hospital for ileocolonoscopy were examined with GIUS and followed for at least 12 months. The clinical endpoints examined were defined as the need for short- or long-time treatment with corticosteroids, changes in the maintenance treatment including drug switch and dose adjustments, hospital admissions and any surgical procedure that could be related to Crohn’s disease. Patients were categorized into 3 groups according to their findings on endoscopy and GIUS: The activity group (1) consisted of patients with activity on GIUS defined as any bowel wall segment ≥3mm and Simple Endoscopic score of Crohn’s disease (SES-CD) >2. The group in transmural remission (2) was defined as all patients with BWT <3mm independent of findings on endoscopy. The final group (3) consisted of the patients with isolated endoscopic remission defined as SES-CD ≤2 and BWT ≥3mm in one or more bowel segment. Results 155 CD patients were included in the study. In total 61/155 patients experienced one or more negative, clinical endpoint during the one year follow up period. 9/155 received treatment with corticosteroids, 50/155 had adjustments in their medical therapy, 32/155 were admitted to the hospital at least once and 18/155 had surgery. In group 1, 44/92 experienced one or more endpoints while the corresponding numbers were 9/40 in group 2 and 8/23 in group 3. The frequency of clinical endpoints were significantly different between the different groups (p=0,020, Fischer’s exact test). Only patients in group 1 were operated. Conclusion The group with transmural remission had fewer patients with negative, clinical endpoints which suggests that GIUS is well suited for distinguishing between CD patients with high or low risk for negative clinical endpoints.

AbstractBackgroundTo assess treatment response, objective measures are superior to clinical improvement in Crohn’s disease [CD]. Intestinal ultrasound [IUS] is an attractive, non-invasive alternative to endoscopy, demonstrating early transmural changes after treatment initiation. Therefore, we investigated IUS and contrast-enhanced ultrasound [CEUS] to predict [early] endoscopic treatment response.MethodsConsecutive patients with endoscopically active CD, starting anti-TNFα therapy, were included. Clinical, biochemical, IUS, and CEUS parameters at baseline [T0], after 4–8 weeks [T1] and 12–34 weeks [T2] were collected. The most severely inflamed segment at endoscopy (highest segmental Simplified Endoscopic Score for Crohn’s Disease [SES-CD]) and IUS (highest segmental bowel wall thickness [BWT]) was identified. At T2, endoscopic response [decrease in SES-CD ≥ 50%] and remission [SES-CD = 0] were scored.ResultsA total of 40 patients were included: 14 reached endoscopic remission and 17 endoscopic response. At T1 (3.1 mm [1.9–4.2] vs 5.3 mm [3.8–6.9], p = 0.005) and T2 (2.0 mm [1.8–3.1] vs 5.1 [3.0–6.3] mm, p = 0.002) BWT was lower in patients with endoscopic remission. At T1 and T2, 18% (area under the receiver operating curve [AUROC]: 0.77; odds ratio [OR]: 10.80, p = 0.012) and 29% [AUROC: 0.833; OR: 37.50, p = 0.006] BWT decrease predicted endoscopic response, respectively. To determine endoscopic remission, BWT 3.2 mm was most accurate [AUROC: 0.94; OR: 39.42, p < 0.0001] at T2. In addition, absence of colour Doppler signal [OR: 13.76, p = 0.03] and the CEUS parameter wash-out rate [OR: 0.76, p = 0.019] improved the prediction model.ConclusionsReduction in BWT, already after 4–8 weeks of follow-up, predicted endoscopic response and remission. CEUS parameters were of limited value. Furthermore, we have provided accurate cut-offs for BWT reflecting endoscopic response and remission at different time points.

Unilateral cortical necrosis is a rare condition, and only described in a few case reports. We present a case of a previously healthy 24-year-old male with acute unilateral cortical necrosis, where contrast-enhanced ultrasound (CEUS) became a valuable diagnostic tool. Antiphospholipid syndrome was subsequently diagnosed. Primary antiphospholipid syndrome is a well-known, but rare cause of cortical necrosis. It promotes thrombosis in renal arteries, capillaries and veins, and usually affects both kidneys. Unilateral cortical necrosis due to antiphospholipid syndrome has, to our knowledge, not been previously described.

Objective. In the following review we outline how ultrasound can be used to measure physiological processes in the gastrointestinal tract. Approach. We have investigated the potential of ultrasound in assessing gastrointestinal physiology including original research regarding both basic methodology and clinical applications. Main results. Our main findings show the use of ultrasound to study esophageal motility, measure volume and contractility of the stomach, assess motility, wall thickness, and perfusion of the small bowel, and evaluate wall vascularization and diameters of the large bowel. Significance. Ultrasound is a widely accessible technology that can be used for both scientific and clinical purposes. Being radiation-free and user friendly, the examination can be frequently repeated enabling longitudinal studies. Furthermore, it does not influence normal GI physiology, thus being useful to estimate motility and subtle changes in physiology. Accordingly, ultrasound scanning and physiological measurements may make a big difference for the scientist and the doctor; and for the patients who receive an efficient work-up.

Introduction: Intestinal ultrasound [IUS] is useful to assess inflammation in ulcerative colitis [UC] patients. We aimed to develop an ultrasonographic activity index using endoscopy as the reference standard. Methods: Patients were included consecutively. IUS was performed within 3 weeks from endoscopy. IUS parameters and endoscopy were compared for each colonic segment [except the rectum]. The best parameters were used to construct a UC-IUS index, which was correlated with endoscopic disease activity using the Spearman's rank test. Results: In 60 patients, 207 colonic segments were evaluated endoscopically. Bowel wall thickness [BWT] > 2.1 mm was optimal to discriminate between Mayo 0 and Mayo 1-3 (sensitivity 82.6%; specificity 93.0%; area under the curve [AUC] 0.910), a cut-off of 3.2 mm was optimal to discriminate between Mayo 0-1 and Mayo 2-3 [sensitivity 89.1%; specificity 92.3%; AUC 0.946] and BWT > 3.9 mm was optimal for detection of Mayo 3 [sensitivity 80.6%; specificity 84.1%; AUC 0.909]. The presence of colour Doppler signal [CDS] predicted active disease, stretches of CDS were associated with Mayo 2-3, lack of haustrations predicted active disease and fat wrapping was associated with severe disease. Inter- and intra-rater intraclass correlation for BWT was substantial. Inter-rater agreement for CDS was substantial and ranged from slight to substantial for haustrations. Intra-rater agreement for CDS was substantial and ranged from moderate to almost perfect for haustrations. The index showed strong correlation with endoscopic disease activity [Mayo: rho 0.830; p < 0.001, UCEIS: rho 0.759; p< 0.001]. Conclusion: We developed an UC-IUS index which showed strong correlation with endoscopic disease activity using internal validation. It is currently being validated in prospective studies.