Oral 2.5% mannitol Small Intestine Contrast Ultrasound for small bowel inflammatory disease: A Surgical-Validated Comparative Study with Magnetic Resonance Enterography

Oral 2.5% mannitol Small Intestine Contrast Ultrasound for small bowel inflammatory disease: A Surgical-Validated Comparative Study with Magnetic Resonance Enterography | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Oral 2.5% mannitol Small Intestine Contrast Ultrasound for small bowel inflammatory disease: A Surgical-Validated Comparative Study with Magnetic Resonance Enterography Ahuang Cai, Yu Xu, Liqin Yu, Hailan Chen, Yan Chen, Shengnan Wu, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7537453/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Objective This study aimed to evaluate the diagnostic performance of Small Intestine Contrast Ultrasound (SICUS) with oral 2.5% mannitol in detecting small bowel inflammatory disease (SBID), and to compare its efficacy with that of Magnetic Resonance Enterography (MRE). Methods A retrospective analysis was conducted in 57 patients with pathologically confirmed SBID who underwent both SICUS and MRE prior to surgery. The sensitivity, specificity, and concordance with surgical findings were calculated for each modality in diagnosing SBID and its complications, including strictures, fistulas, and abscesses. Results Both SICUS and MRE achieved a detection rate of 96.5% for SBID. SICUS showed higher sensitivity than MRE for identifying strictures (87.0% vs. 83.3%) and fistulas (82.8% vs. 65.5%), with strong consistency with surgical findings (κ = 0.83 for fistulas). For detecting abscesses, the sensitivity was 81.8% for both modalities. Notably, SICUS achieved 100% specificity for all complications. Additional advantages of SICUS include real-time dynamic evaluation, high spatial resolution, reduced interference from intestinal gas, and greater accessibility in primary care settings. Conclusions SICUS is a reliable, non-invasive, and cost-effective imaging technique for evaluating SBID and its complications. It provides diagnostic performance comparable to or exceeding that of MRE, particularly for strictures and fistulas. Given its repeatability and suitability for patients unable to undergo MRE, SICUS represents a practical alternative in clinical practice. small bowel inflammatory disorders Small Intestine Contrast Ultrasound Magnetic Resonance Enterography mannitol diagnosis Figures Figure 1 Figure 2 Figure 3 1. Introduction Small bowel inflammatory disease (SBID), encompassing conditions such as Crohn’s disease (CD), nonspecific enteritis, and intestinal tuberculosis, represents a common inflammatory disorder of the small intestine 1 . Global epidemiological data indicate a rising incidence of SBID, with an increasing proportion of refractory cases 2 .Due to the unique anatomical structure of the small intestine, characterized by its tortuous shape, rapid peristalsis, long and free lumen, and numerous folds, traditional gastrointestinal endoscopy is limited in its ability to comprehensively and accurately assess small bowel lesions 3 . SBID often present with an insidious onset and nonspecific symptoms, leading to difficulties in early diagnosis and potential delays in treatment. These diseases are further associated with increased surgical complications and healthcare costs, underscoring the urgent need for timely detection and effective management 4 . With advancements in medical imaging, several modalities have been developed for the evaluation of small bowel disease, including Small Bowel Endoscopy (SBE), Computed Tomography Enterograph (CTE), and Magnetic Resonance Enterography (MRE). Each has distinct advantages and limitations. As the gold standard for SIBD diagnosis, SBE allows biopsy of diseased tissue in the small bowel mucosa. However, it is invasive and contraindicated in cases of significant luminal narrowing, where passage of the colonoscope is not feasible 5 . CTE provides clear visualization of the bowel wall and surrounding structures, but repeated follow-up examinations raise concerns about cumulative radiation exposure 6 .MRE offers excellent soft tissue contrast, multiplanar imaging, and avoids ionizing radiation, but its limitations include high cost, long examination time, limited availability in primary care settings, and the need for considerable patient cooperation 7 . These limitations highlight the need for a more accurate, efficient, and cost-effective diagnostic alternative for SBID. Ultrasound is increasingly applied as a front-line tool in SBID evaluation. The most common sonographic feature is bowel wall thickening; however, this finding is nonspecific and may also be observed in infectious, vascular, or ischemic conditions. Therefore, additional parameters—such as bowel wall stratification, vascularity, anatomical predilection sites, and lesion length—should be considered in the differential diagnosis 8 – 11 . In CD, the disease most frequently involves the terminal ileum and right colon, with segmental thickening in a characteristic skip pattern, where diseased and normal segments alternate with sharp demarcations. Mesenteric fat proliferation (“creeping fat”) is often observed adjacent to inflamed bowel loops and correlates with inflammatory severity. Marked wall thickening, loss of normal wall stratification, and increased color Doppler flow (CDFI) within the wall further suggest active inflammation 8 – 11 . Oral 2.5% mannitol Small Intestine Contrast Ultrasound (SICUS) has recently emerged as a promising diagnostic modality for SBID. By distending the small bowel with orally administered mannitol solution, SICUS effectively reduces intraluminal gas interference and enables clear visualization of intestinal morphology and pathological changes 12 . This study aims to systematically evaluate the diagnostic performance of SICUS in detecting SBID and to compare its efficacy with MRE, thereby providing evidence for a simpler and more accessible imaging modality in clinical practice. 2. Materials and Methods 2.1 Study Design and Participants This retrospective study included 82 patients with suspected small bowel disease who underwent small bowel examination and surgical treatment at the First Affiliated Hospital of Fujian Medical University between June 2019 and October 2023. Finally, a total of 57 patients with inflammatory lesions were selected and evaluated (Fig. 1 ) by two senior sonographers according to the the inclusion and exclusion criteria as follows: 2.1.1 Inclusion criteria: (1) Patients presenting with clinical manifestations suggestive of small-bowel disease, such as unexplained chronic abdominal pain, diarrhea, gastrointestinal bleeding, anemia, or weight loss, supported by at least one abnormal laboratory or imaging finding (e.g., elevated inflammatory markers, hypoalbuminemia, anemia, or positive findings on prior CT, enterography, or endoscopy); (2) All patients underwent SICUS with oral administration of 2.5% mannitol; (3) All patients underwent MRE, with the most recent preoperative scan included for patients who had multiple examinations within six months. In the majority of cases, MRE was performed prospectively within 72 hours before surgery following the standardized imaging protocol; (4) All patients underwent surgical treatment, and surgical pathology was used as the diagnostic reference standard. 2.1.2 Exclusion criteria: (1) Absence of pathological confirmation by surgical specimens; (2) Poor bowel preparation resulting in failure of SICUS to visualize the small intestine; (3) Intolerance to oral mannitol; (4) Severe cardiac, hepatic, or renal dysfunction. 2.2 Instruments and Methods Oral 2.5% mannitol SICUS Examination: All examinations were performed in the supine position using a GE Voluson E10 Color Doppler Ultrasound system (convex array: 3.5–10.0 MHz; linear array: 7.5–14 MHz) by two sonographers with intermediate or senior professional titles and more than 10 years of experience in abdominal ultrasound. Patients ingested 2.5% isotonic mannitol solution (up to 2000 mL) to achieve adequate small bowel distension. The small intestine was scanned sequentially from the duodenum to the ileocecal junction. When necessary, additional warm water was administered to ensure optimal imaging. Intestinal wall thickness, wall stratification, peristalsis, lumen narrowing, and surrounding structures (e.g., lymph nodes, fistulas, abscesses) were evaluated. CDFI was used to assess vascularity. Inflammatory activity was graded using the Limberg classification 13 . MRE Examination: MRE was performed using a Siemens Magnetom Verio 3.0T MRI scanner. Patients received 1500 mL of 2.5% mannitol solution orally 1 hour prior to scanning. Ten minutes before imaging, 20 mg of hyoscine butylbromide was intramuscularly administered. MRI sequences included axial and coronal T2-weighted imaging (T2WI), T1-weighted imaging (T1WI), and diffusion-weighted imaging (DWI). For contrast-enhanced imaging, gadopentetate dimeglumine (0.1 mmol/kg) was injected intravenously at 2 mL/s. Dynamic 3D VIBE sequences were obtained at 30, 60, and 90 seconds post-injection. Standardization and Blinding: To minimize preparation-related bias, a standardized imaging sequence was implemented prospectively. Whenever possible, SICUS was performed within 48 hours before surgery, followed by MRE within 72 hours. For patients who had previously undergone MRE within six months before surgery, their most recent preoperative scan was used for analysis. For patients who also underwent endoscopy, the interval between endoscopic procedures and imaging was maintained at ≥ 7 days to avoid residual bowel preparation or mucosal changes affecting image quality. SICUS and MRE were interpreted independently by two readers in each modality (two sonographers for SICUS and two radiologists for MRE, each with more than ten years of gastrointestinal imaging experience). Readers were blinded to each other’s results as well as to all clinical, endoscopic, and surgical findings. Discrepancies were resolved by consensus; if no consensus was reached, a third senior radiologist adjudicated. Interobserver agreement was evaluated using Cohen’s kappa statistics. 2.3 Ultrasound Image Analysis Lesion Location: The duodenum, jejunum, and ileum were identified based on the anatomical location and morphology of the small intestine. The upper duodenum is connected to the stomach pylorus, and it continues into the jejunum via the ascending part, wrapping around the head of the pancreas in a "C" shape. The jejunum is mostly located in the upper left abdomen, and the ileum is mostly in the lower right abdomen. The jejunum has prominent folds and active peristalsis, while the ileum’s folds gradually diminish and disappear, with slower peristalsis. The terminal ileum is the portion of the ileum located within 20 cm of the ileocecal valve. Intestinal Wall Thickening: Three measurements were taken in both longitudinal and transverse planes, with the average value > 3 mm being considered as intestinal wall thickening 14 . Abnormal Intestinal Wall Layers: The normal ultrasound image of the intestinal wall shows the following layers from the inside out: a high echogenic interface between the lumen and the mucosa, a hypoechoic mucosal layer containing the mucosal muscle, a high echogenic submucosa, a hypoechoic muscularis propria, and a high echogenic interface between the serosal layer and surrounding tissue. A loss of these layers is considered abnormal 15 . Narrowing: SICUS shows intestinal wall thickness > 3 mm and the maximum inner diameter of the lumen 25 mm), as the diagnostic criteria for narrowing 16 – 18 . Intestinal Fistula: An abnormal communication between the intestinal lumen and the mesentery, other intra-abdominal hollow organs, the peritoneal cavity, or the skin 19 . On ultrasonography, it is characterized by disruption of the continuity of the intestinal wall, accompanied by a hypoechoic tubular structure adjacent to the bowel wall. The presence of intraluminal gas results in marked echogenicity. Demonstration of communication with the peritoneal cavity or abdominal organs is suggestive of an enterocutaneous fistula. Abscess: An irregular mass with thick walls, mixed echogenicity (liquid or liquid-containing), often located around an intestinal fistula. Sometimes, gas shadows may be visible inside, and posterior acoustic enhancement is commonly seen. 2.4 Statistical Analysis All data were analyzed using the SPSS 25.0(IBM Corp., Armonk, NY, USA) statistical analysis software. For continuous variables, data that followed a normal distribution were expressed as the mean ± standard deviation \(\:\left(\overline{\text{X}}\pm\:\text{S}\right)\) , while data that did not follow a normal distribution were expressed as the median (interquartile range) (P25, P75). Categorical variables were expressed as percentages. The consistency analysis of SICUS in diagnosing small bowel inflammatory lesions, complications, and surgical outcomes was performed using the kappa coefficient. A kappa value of < 0.2 indicates poor consistency; 0.2–0.4 indicates fair consistency; 0.4–0.6 indicates moderate consistency; 0.6–0.8 indicates strong consistency; and 0.8–1.0 indicates very strong consistency. The diagnostic performance of SICUS and MRE for SBID was compared using the McNemar test (paired chi-square test), and a P value of < 0.05 was considered statistically significant. 3. Results 3.1 Patient Characteristics A total of 57 patients with pathologically confirmed inflammatory lesions were included in this study, comprising 36 males (63.2%) and 21 females (36.8%), with a mean age of 40.0 ± 13.9 years. The predominant clinical manifestation was abdominal pain, observed in 51 patients (89.5%). Other symptoms included altered bowel habits in 14 (24.6%), diarrhea in 9 (15.8%), vomiting in 5 (8.8%), abdominal distension in 3 (5.3%), perianal lesions in 2 (3.5%), hematochezia in 2 (3.5%), fever in 2 (3.5%), and melena in 1 (1.8%) (Table 1 ). Postoperative pathological diagnoses confirmed inflammatory lesions in all 57 patients, including CD in 50 cases, nonspecific enteritis in 5, intestinal tuberculosis in 1, and cryptogenic multifocal ulcerous stenosing enteritis (CMUSE) in 1. Table 1 Demographic and Clinical Characteristics of SBID (N = 57) Characteristic Number of Cases (n) Percentage (%) Sex Male 36 63.2 Female 21 36.8 Age [years, ‾x ± s] - 40.0 ± 13.9 Clinical manifestations Abdominal pain 51 85.9 Altered bowel habits 14 24.6 Diarrhea 9 15.8 Vomiting 5 8.8 Abdominal distension 3 5.3 Perianal lesions 2 3.5 Hematochezia 2 3.5 Fever 2 3.5 Melena 1 1.8 3.2 Diagnostic Consistency of SICUS With Surgical Findings in SBID Complications Among the 57 patients with surgically confirmed small bowel inflammatory lesions, 54 presented with strictures, 29 with enteric fistulas, and 11 with abscesses. For strictures, SICUS demonstrated a sensitivity of 87.0% (95% CI: 75.2–94.3) and a specificity of 100% (95% CI: 29.2–100), showing moderate agreement with surgical findings (κ = 0.41). For enteric fistulas—including 24 enteroenteric, 2 enterovesical, and 3 complex fistulas—SICUS achieved a sensitivity of 82.8% (95% CI: 68.4–97.1) and a specificity of 100% (95% CI: 88.4–100), revealing strong agreement with surgical localization (κ = 0.83). For abscesses—4 located posterior to the ileocecal region, 5 in the right lower abdominal/pelvic mesentery, and 2 pelvic abscesses associated with enterovesical fistulas—SICUS yielded a sensitivity of 81.8% (95% CI: 59.7–100) and a specificity of 100% (95% CI: 92.3–100), demonstrating excellent agreement with surgical findings (κ = 0.88).(Table 2 ) Table 2 Diagnostic performance of SICUS for SBID-related complications compared with surgical findings (N = 57) Complication Intraoperative Diagnosis (n) True Positive (n) False Positive (n) False Negative (n) True Negative (n) Sensitivity (%) (95% CI) Specificity (%) (95% CI) Accuracy (%) (95% CI) Kappa Coefficient stenosis 54 47 0 7 3 87.0(75.2,94.3) 100(29.2,100) 87.7(76.3,94.7) 0.41 fistulas 29 24 0 5 28 82.8(68.4,97.1) 100(88.4,100) 91.2(80.7,97.0) 0.83 abscesses 11 9 0 2 46 81.8(59.7,100) 100(92.3,100) 96.5(90.1,100) 0.88 3.3 Diagnostic Performance of SICUS in SBID and SBID Complications SICUS demonstrated a positive detection rate of 96.5% (55/57) for SBID, identical to that of MRE (96.5%). For complications, the sensitivity of SICUS was 87.0% (95% CI: 75.2–94.3) for strictures, 82.8% (95% CI: 68.4–97.1) for enteric fistulas, and 81.8% (95% CI: 59.7–100.0) for abscesses, with a specificity of 100% for all. Compared with MRE, SICUS showed numerically higher sensitivity for detecting strictures (87.0% vs 83.3%) and fistulas (82.8% vs 65.5%). However, McNemar’s test revealed no statistically significant differences between SICUS and MRE in the diagnosis of strictures (P = 0.803), fistulas (P = 0.301), or abscesses (P = 0.480) (Fig. 2 ) . Thus, although SICUS exhibited slightly higher sensitivity values for certain complications, these differences were attributable to random sampling variation rather than true differences in diagnostic efficacy. Overall, no significant difference was observed between the two modalities in the diagnosis of SBID (P = 1.00). (Table 3 , Fig. 3 ) Table 3 Sensitivity, specificity, and accuracy of SICUS versus MRE in detecting SBID-related complications (N = 57) Complication Intraoperative Diagnosis (n) Imaging Modality True Positive (n) False Positive (n) False Negative (n) True Negative (n) Sensitivity (%) (95% CI) Specificity (%) (95% CI) Accuracy (%) (95% CI) P value vs. MRE (McNemar’s test) stenosis 54 SICUS 47 0 7 3 87.0 (75.2,94.3) 100 (29.2,100) 87.7 (76.3,94.7) 0.803 (sensitivity difference) MRE 45 0 9 3 83.3 (71.1,91.5) 100 (29.2,100) 84.2 (72.4,92.1) - fistulas 29 SICUS 24 0 5 28 82.8 (68.4,97.1) 100 (88.4,100) 91.2 (80.7,97.0) 0.301 (sensitivity difference) MRE 19 0 10 28 65.5 (45.7,82.1) 100 (88.4,100) 82.5 (70.6,90.9) - abscesses 11 SICUS 9 0 2 46 81.8 (59.7,100) 100 (92.3,100) 96.5 (90.1,100) 0.480 (sensitivity difference) MRE 9 1 2 45 81.8 (59.7,100) 97.8 (90.5,100) 94.7 (87.9,98.5) - 4. Discussion SIBD presents with a broad spectrum of nonspecific clinical symptoms, including abdominal pain, diarrhea, gastrointestinal bleeding, bloating, and weight loss 20 . In our study, abdominal pain was the most common manifestation (89.5%), followed by altered bowel habits (24.6%). Due to the limited visualization of the entire small intestine by conventional endoscopy, these nonspecific symptoms frequently lead to misdiagnosis or missed diagnosis. Therefore, SIBD should be considered in patients with recurrent, unexplained gastrointestinal complaints despite negative findings on routine endoscopy. In this context, oral 2.5% mannitol SICUS demonstrated substantial diagnostic value, with a positivity rate of 96.5% in identifying SIBD. By effectively distending the small intestine and minimizing gas interference, SICUS enables clear visualization of intestinal structures and lesions 21 . Moreover, it allows dynamic assessment of bowel wall morphology and peristalsis, enhancing the detection of stenotic and rigid segments—particularly during the "peak effect" phase—thus reducing false positives. In our study, SICUS showed a sensitivity of 87.0% (95% CI: 75.2–94.3) for detecting stenosis, slightly higher than that of MRE (83.3%; 95% CI: 71.1–91.5). For fistulas, its real-time scanning capability allowed direct visualization of contrast flow 22 , resulting in higher sensitivity (82.8%; 95% CI: 68.4–97.1) compared to MRE (65.5%; 95% CI: 45.7–82.1), with strong concordance with surgical findings (κ = 0.83). In detecting abscesses, SICUS provided a superior acoustic window due to improved bowel preparation and distension 23 , achieving diagnostic performance comparable to MRE, with no statistically significant difference (P > 0.05). Importantly, paired statistical analysis using the McNemar test confirmed that there were no significant differences in diagnostic efficacy between SICUS and MRE for SIBD complications (all P > 0.05). Nevertheless, SICUS demonstrated distinct clinical advantages. First, as a noninvasive and radiation-free technique, its per-examination cost is approximately one-fifth that of MRE, making it particularly suitable for patients requiring repeated follow-up, such as those undergoing remission monitoring for CD. Second, SICUS enables real-time dynamic observation of intestinal peristalsis, providing a more intuitive assessment of proximal dilatation secondary to stricture. Although this advantage did not yield a statistically significant difference (P = 0.803), it remains clinically meaningful, especially in primary care settings where MRE accessibility is limited. In this study, both SICUS and MRE demonstrated high diagnostic performance for SIBD, each achieving a positive detection rate of 96.5%. The few missed cases may be attributable to examinations conducted during remission phases. Compared with previous studies, such as Zhu et al. (88.3%) 21 , the higher diagnostic yield observed here may be explained by the use of surgical confirmation as the reference standard and by the advanced expertise of our gastrointestinal ultrasonography specialists 24 , 25 . This study has several strengths and novel aspects. Firstly, surgical pathology was used as the gold standard, providing objective validation of imaging findings. Secondly, by focusing on patients with confirmed and complicated SBID, it offered valuable insights into the performance of SICUS in severe cases. Thridly, all examinations were performed by an experienced specialist, which ensured high image quality and diagnostic accuracy. Fourthly, the study specifically evaluated the capacity of SICUS to detect complications such as strictures and fistulas, highlighting its clinical utility. Nonetheless, several limitations should be acknowledged. This was a single-center study with a relatively small sample size, which may restrict the generalizability of the findings. The use of surgical results as the gold standard may have introduced selection bias and potentially led to an overestimation of diagnostic performance. Although the SICUS examinations were conducted by two experienced physicians, inter-operator agreement was not formally assessed. Furthermore, the small subgroup sample for abscesses (n = 11) may have resulted in limited statistical power and underestimation of potential differences between modalities. Future studies should therefore include large-scale, multicenter cohorts and formal inter-operator consistency assessments to further validate the diagnostic efficacy of SICUS and clarify subtle differences compared with MRE. 5. Conclusions SICUS is a noninvasive, radiation-free, cost-effective, and well-tolerated technique for the evaluation of SBID. It demonstrates high diagnostic sensitivity and accuracy for SIBD and its complications, with particular advantages in detecting strictures and fistulas. Although its overall diagnostic performance was not statistically superior to MRE (P > 0.05), SICUS offers distinct clinical advantages, including real-time dynamic assessment, low cost, and wide accessibility. These features make SICUS a valuable alternative to MRE, particularly for patients requiring repeated follow-up or in primary healthcare settings, thereby facilitating the early diagnosis and management of SIBD. Declarations Author contributions: Ahuang Cai: Conceptualization, Formal Analysis, Investigation, Methodology, Software, Writing – original draft. Yu Xu: Formal Analysis,Data curation, Investigation, Funding acquisition, Writing – original draft. Liqin Yu:Formal Analysis, Data curation, Investigation, Writing – original draft. Hailan Chen: Acquisition, analysis, or interpretation of data. Yan Chen: Acquisition, analysis, or interpretation of data. Shengnan Wu: Acquisition, analysis, or interpretation of data. Xuan Wang: Acquisition, analysis, or interpretation of data. Linglin Wei: Methodology, Project administration, Writing – review and editing. Xinxiu Liu: Conceptualization, Project administration, Resources, Supervision, Validation, Writing – review and editing. Funding Statement: The authors declare that financial support was received for the research and/or publication of this article. This study was supported by Fujian Medical University QiHang Fund [grant no. 2022QH1093]. Data availability statement: The original contributions presented in this study are included in this article/Supplementary material, further inquiries can be directed to the corresponding author. RefeEthics statement: This study was in accordance with the Ethical Standards of the Institutional Ethics Committee of First Affiliated Hospital of Fujian Medical University and with the 1964 Helsinki declaration and its later amendments or comparable Ethical Standards. Ethics batch number: IEC-FOM-013-2.0. As a purely retrospective review of medical records that did not involve any personally identifiable information, the requirement for informed consent was waived.rences IRB approval status: This study was approved by The Ethics Committee of the First Affiliated Hospital of Fujian Medical University (IRB [2020]190). Patient Consent to Publish: The requirement for informed patient consent was waived because of the anonymous nature of the data. 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Pallotta N, Vincoli G, Montesani C, Chirletti P, Pronio A, Caronna R, Ciccantelli B, Romeo E, Marcheggiano A, Corazziari E. Small intestine contrast ultrasonography (SICUS) for the detection of small bowel complications in crohn's disease: a prospective comparative study versus intraoperative findings. Inflamm Bowel Dis. 2012;18(1):74–84. Allocca M, Fiorino G, Bonifacio C, et al. Comparative Accuracy of Bowel Ultrasound Versus Magnetic Resonance Enterography in Combination With Colonoscopy in Assessing Crohn's Disease and Guiding Clinical Decision-making. J Crohns Colitis. 2018;12(11):1280–7. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7537453","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":519923124,"identity":"613cf039-e573-423f-a7e1-a88e05e33250","order_by":0,"name":"Ahuang Cai","email":"","orcid":"","institution":"the First Affiliated Hospital of Fujian Medical University","correspondingAuthor":false,"prefix":"","firstName":"Ahuang","middleName":"","lastName":"Cai","suffix":""},{"id":519923125,"identity":"2493afb2-40a6-4d97-83c1-1b53559ae575","order_by":1,"name":"Yu Xu","email":"","orcid":"","institution":"the First Affiliated Hospital of Fujian Medical University","correspondingAuthor":false,"prefix":"","firstName":"Yu","middleName":"","lastName":"Xu","suffix":""},{"id":519923126,"identity":"a2ee7bc0-83ff-4c7f-bed3-6c9d91d9e156","order_by":2,"name":"Liqin Yu","email":"","orcid":"","institution":"the First Affiliated Hospital of Fujian Medical University","correspondingAuthor":false,"prefix":"","firstName":"Liqin","middleName":"","lastName":"Yu","suffix":""},{"id":519923127,"identity":"2f397073-d534-4e4e-9b8e-8b3744674083","order_by":3,"name":"Hailan Chen","email":"","orcid":"","institution":"the First Affiliated Hospital of Fujian Medical University","correspondingAuthor":false,"prefix":"","firstName":"Hailan","middleName":"","lastName":"Chen","suffix":""},{"id":519923128,"identity":"06255139-f1d5-4fbf-b80a-e0901dfa26a8","order_by":4,"name":"Yan Chen","email":"","orcid":"","institution":"the First Affiliated Hospital of Fujian Medical University","correspondingAuthor":false,"prefix":"","firstName":"Yan","middleName":"","lastName":"Chen","suffix":""},{"id":519923129,"identity":"0cb692c2-115c-410c-ae80-7896d601ab0b","order_by":5,"name":"Shengnan Wu","email":"","orcid":"","institution":"the First Affiliated Hospital of Fujian Medical University","correspondingAuthor":false,"prefix":"","firstName":"Shengnan","middleName":"","lastName":"Wu","suffix":""},{"id":519923132,"identity":"2ec61e1d-5a79-4eac-bfa0-b0ea4f0e1db4","order_by":6,"name":"Xuan Wang","email":"","orcid":"","institution":"the First Affiliated Hospital of Fujian Medical University","correspondingAuthor":false,"prefix":"","firstName":"Xuan","middleName":"","lastName":"Wang","suffix":""},{"id":519923133,"identity":"91eed08b-d6e2-4cb4-b8f6-c91c62283700","order_by":7,"name":"Linglin Wei","email":"","orcid":"","institution":"the First Affiliated Hospital of Fujian Medical University","correspondingAuthor":false,"prefix":"","firstName":"Linglin","middleName":"","lastName":"Wei","suffix":""},{"id":519923135,"identity":"3cc4c241-b4e5-4b4e-8970-8adf7771390f","order_by":8,"name":"Xinxiu Liu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAu0lEQVRIiWNgGAWjYBACPhCRwMDAw8De2PjwAzFa2OBaeA43G0sQrQUMJNLbBHiI0sJ+xkzi4Y7DMgY3H7YxSDDYyek2ENLCk2NskHgmjcfgdmLbgwKGZGOzAwQdlmP4ILHNBqSl3UCC4UDiNoJa+N8YHEhsk+AxuHkQSBKlRQJmyw1GorU8KzZIbEvjkTyTCAxkAyL8ws+fvE3yZ9the77jxx8+/FBhJ0dQCxowIE35KBgFo2AUjAIcAACuiDyR7kxNTAAAAABJRU5ErkJggg==","orcid":"","institution":"the First Affiliated Hospital of Fujian Medical University","correspondingAuthor":true,"prefix":"","firstName":"Xinxiu","middleName":"","lastName":"Liu","suffix":""}],"badges":[],"createdAt":"2025-09-04 15:08:19","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7537453/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7537453/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":92274672,"identity":"473e1c5c-0752-4874-9f94-b13375c94fa5","added_by":"auto","created_at":"2025-09-26 15:27:31","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":497045,"visible":true,"origin":"","legend":"","description":"","filename":"Manuscript9.41.docx","url":"https://assets-eu.researchsquare.com/files/rs-7537453/v1/d79998f08112064b945f7388.docx"},{"id":92274650,"identity":"49caa705-1343-46b7-bf5f-bf992a89e278","added_by":"auto","created_at":"2025-09-26 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15:27:36","extension":"png","order_by":6,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":59443,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-7537453/v1/57e2df24f5063e72ec485582.png"},{"id":92274723,"identity":"5a9037f1-57b3-4212-b29f-ce21ec337aa7","added_by":"auto","created_at":"2025-09-26 15:27:34","extension":"png","order_by":7,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":244206,"visible":true,"origin":"","legend":"","description":"","filename":"Onlinefloatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-7537453/v1/edd45ec4e9f195f7fe239adf.png"},{"id":92274667,"identity":"fb6d3261-110f-42a4-ad7d-42bed74d2886","added_by":"auto","created_at":"2025-09-26 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15:27:36","extension":"html","order_by":10,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":96451,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7537453/v1/82069a78d7a5e5f4109656e1.html"},{"id":92274807,"identity":"79fbe738-2525-4304-b850-ace5c3beabff","added_by":"auto","created_at":"2025-09-26 15:27:39","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":144247,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ePatient selection flowchart for small bowel inflammatory lesion analysis.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-7537453/v1/36c16fc0a1c4a0377923aec0.png"},{"id":92274685,"identity":"38ee9d01-33fe-4b85-b317-6e940c53a916","added_by":"auto","created_at":"2025-09-26 15:27:31","extension":"jpeg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":177557,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eImaging Features of Small Bowel Inflammatory Complications Detected by SICUS and MRE\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"floatimage2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7537453/v1/b247a9b382d067bbcea4d235.jpeg"},{"id":92274636,"identity":"1b9508c9-ae0c-42a4-b347-3f433575be81","added_by":"auto","created_at":"2025-09-26 15:27:29","extension":"jpeg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":130470,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eComparison of SICUS and MRE in diagnosing stenosis, fistulas, and abscesses.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"floatimage3.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7537453/v1/fb7a67b4cceeaeaf5eef9f95.jpeg"},{"id":101184038,"identity":"421af123-df20-4558-9d4b-839ca492c432","added_by":"auto","created_at":"2026-01-27 05:25:49","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1407263,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7537453/v1/11d0fa0f-0f21-4e9b-a75d-a199b62d2db8.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Oral 2.5% mannitol Small Intestine Contrast Ultrasound for small bowel inflammatory disease: A Surgical-Validated Comparative Study with Magnetic Resonance Enterography","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eSmall bowel inflammatory disease (SBID), encompassing conditions such as Crohn\u0026rsquo;s disease (CD), nonspecific enteritis, and intestinal tuberculosis, represents a common inflammatory disorder of the small intestine\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e. Global epidemiological data indicate a rising incidence of SBID, with an increasing proportion of refractory cases\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e.Due to the unique anatomical structure of the small intestine, characterized by its tortuous shape, rapid peristalsis, long and free lumen, and numerous folds, traditional gastrointestinal endoscopy is limited in its ability to comprehensively and accurately assess small bowel lesions\u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e. SBID often present with an insidious onset and nonspecific symptoms, leading to difficulties in early diagnosis and potential delays in treatment. These diseases are further associated with increased surgical complications and healthcare costs, underscoring the urgent need for timely detection and effective management\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eWith advancements in medical imaging, several modalities have been developed for the evaluation of small bowel disease, including Small Bowel Endoscopy (SBE), Computed Tomography Enterograph (CTE), and Magnetic Resonance Enterography (MRE). Each has distinct advantages and limitations. As the gold standard for SIBD diagnosis, SBE allows biopsy of diseased tissue in the small bowel mucosa. However, it is invasive and contraindicated in cases of significant luminal narrowing, where passage of the colonoscope is not feasible\u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e. CTE provides clear visualization of the bowel wall and surrounding structures, but repeated follow-up examinations raise concerns about cumulative radiation exposure\u003csup\u003e\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e.MRE offers excellent soft tissue contrast, multiplanar imaging, and avoids ionizing radiation, but its limitations include high cost, long examination time, limited availability in primary care settings, and the need for considerable patient cooperation\u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e. These limitations highlight the need for a more accurate, efficient, and cost-effective diagnostic alternative for SBID.\u003c/p\u003e\u003cp\u003eUltrasound is increasingly applied as a front-line tool in SBID evaluation. The most common sonographic feature is bowel wall thickening; however, this finding is nonspecific and may also be observed in infectious, vascular, or ischemic conditions. Therefore, additional parameters\u0026mdash;such as bowel wall stratification, vascularity, anatomical predilection sites, and lesion length\u0026mdash;should be considered in the differential diagnosis\u003csup\u003e\u003cspan additionalcitationids=\"CR9 CR10\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e. In CD, the disease most frequently involves the terminal ileum and right colon, with segmental thickening in a characteristic skip pattern, where diseased and normal segments alternate with sharp demarcations. Mesenteric fat proliferation (\u0026ldquo;creeping fat\u0026rdquo;) is often observed adjacent to inflamed bowel loops and correlates with inflammatory severity. Marked wall thickening, loss of normal wall stratification, and increased color Doppler flow (CDFI) within the wall further suggest active inflammation\u003csup\u003e\u003cspan additionalcitationids=\"CR9 CR10\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eOral 2.5% mannitol Small Intestine Contrast Ultrasound (SICUS) has recently emerged as a promising diagnostic modality for SBID. By distending the small bowel with orally administered mannitol solution, SICUS effectively reduces intraluminal gas interference and enables clear visualization of intestinal morphology and pathological changes\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eThis study aims to systematically evaluate the diagnostic performance of SICUS in detecting SBID and to compare its efficacy with MRE, thereby providing evidence for a simpler and more accessible imaging modality in clinical practice.\u003c/p\u003e"},{"header":"2. Materials and Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003e2.1 Study Design and Participants\u003c/h2\u003e\u003cp\u003eThis retrospective study included 82 patients with suspected small bowel disease who underwent small bowel examination and surgical treatment at the First Affiliated Hospital of Fujian Medical University between June 2019 and October 2023. Finally, a total of 57 patients with inflammatory lesions were selected and evaluated (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e1\u003c/span\u003e) by two senior sonographers according to the the inclusion and exclusion criteria as follows:\u003c/p\u003e\u003cdiv id=\"Sec4\" class=\"Section3\"\u003e\u003ch2\u003e2.1.1 Inclusion criteria:\u003c/h2\u003e\u003cp\u003e(1) Patients presenting with clinical manifestations suggestive of small-bowel disease, such as unexplained chronic abdominal pain, diarrhea, gastrointestinal bleeding, anemia, or weight loss, supported by at least one abnormal laboratory or imaging finding (e.g., elevated inflammatory markers, hypoalbuminemia, anemia, or positive findings on prior CT, enterography, or endoscopy); (2) All patients underwent SICUS with oral administration of 2.5% mannitol; (3) All patients underwent MRE, with the most recent preoperative scan included for patients who had multiple examinations within six months. In the majority of cases, MRE was performed prospectively within 72 hours before surgery following the standardized imaging protocol; (4) All patients underwent surgical treatment, and surgical pathology was used as the diagnostic reference standard.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec5\" class=\"Section3\"\u003e\u003ch2\u003e2.1.2 Exclusion criteria:\u003c/h2\u003e\u003cp\u003e(1) Absence of pathological confirmation by surgical specimens; (2) Poor bowel preparation resulting in failure of SICUS to visualize the small intestine; (3) Intolerance to oral mannitol; (4) Severe cardiac, hepatic, or renal dysfunction.\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv id=\"Sec6\" class=\"Section2\"\u003e\u003ch2\u003e2.2 Instruments and Methods\u003c/h2\u003e\u003cp\u003eOral 2.5% mannitol SICUS Examination: All examinations were performed in the supine position using a GE Voluson E10 Color Doppler Ultrasound system (convex array: 3.5\u0026ndash;10.0 MHz; linear array: 7.5\u0026ndash;14 MHz) by two sonographers with intermediate or senior professional titles and more than 10 years of experience in abdominal ultrasound. Patients ingested 2.5% isotonic mannitol solution (up to 2000 mL) to achieve adequate small bowel distension. The small intestine was scanned sequentially from the duodenum to the ileocecal junction. When necessary, additional warm water was administered to ensure optimal imaging. Intestinal wall thickness, wall stratification, peristalsis, lumen narrowing, and surrounding structures (e.g., lymph nodes, fistulas, abscesses) were evaluated. CDFI was used to assess vascularity. Inflammatory activity was graded using the Limberg classification\u003csup\u003e\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eMRE Examination: MRE was performed using a Siemens Magnetom Verio 3.0T MRI scanner. Patients received 1500 mL of 2.5% mannitol solution orally 1 hour prior to scanning. Ten minutes before imaging, 20 mg of hyoscine butylbromide was intramuscularly administered. MRI sequences included axial and coronal T2-weighted imaging (T2WI), T1-weighted imaging (T1WI), and diffusion-weighted imaging (DWI). For contrast-enhanced imaging, gadopentetate dimeglumine (0.1 mmol/kg) was injected intravenously at 2 mL/s. Dynamic 3D VIBE sequences were obtained at 30, 60, and 90 seconds post-injection.\u003c/p\u003e\u003cp\u003eStandardization and Blinding: To minimize preparation-related bias, a standardized imaging sequence was implemented prospectively. Whenever possible, SICUS was performed within 48 hours before surgery, followed by MRE within 72 hours. For patients who had previously undergone MRE within six months before surgery, their most recent preoperative scan was used for analysis. For patients who also underwent endoscopy, the interval between endoscopic procedures and imaging was maintained at \u0026ge;\u0026thinsp;7 days to avoid residual bowel preparation or mucosal changes affecting image quality.\u003c/p\u003e\u003cp\u003eSICUS and MRE were interpreted independently by two readers in each modality (two sonographers for SICUS and two radiologists for MRE, each with more than ten years of gastrointestinal imaging experience). Readers were blinded to each other\u0026rsquo;s results as well as to all clinical, endoscopic, and surgical findings. Discrepancies were resolved by consensus; if no consensus was reached, a third senior radiologist adjudicated. Interobserver agreement was evaluated using Cohen\u0026rsquo;s kappa statistics.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\u003ch2\u003e2.3 Ultrasound Image Analysis\u003c/h2\u003e\u003cp\u003e\u003col\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eLesion Location: The duodenum, jejunum, and ileum were identified based on the anatomical location and morphology of the small intestine. The upper duodenum is connected to the stomach pylorus, and it continues into the jejunum via the ascending part, wrapping around the head of the pancreas in a \"C\" shape. The jejunum is mostly located in the upper left abdomen, and the ileum is mostly in the lower right abdomen. The jejunum has prominent folds and active peristalsis, while the ileum\u0026rsquo;s folds gradually diminish and disappear, with slower peristalsis. The terminal ileum is the portion of the ileum located within 20 cm of the ileocecal valve.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eIntestinal Wall Thickening: Three measurements were taken in both longitudinal and transverse planes, with the average value\u0026thinsp;\u0026gt;\u0026thinsp;3 mm being considered as intestinal wall thickening\u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eAbnormal Intestinal Wall Layers: The normal ultrasound image of the intestinal wall shows the following layers from the inside out: a high echogenic interface between the lumen and the mucosa, a hypoechoic mucosal layer containing the mucosal muscle, a high echogenic submucosa, a hypoechoic muscularis propria, and a high echogenic interface between the serosal layer and surrounding tissue. A loss of these layers is considered abnormal\u003csup\u003e\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eNarrowing: SICUS shows intestinal wall thickness\u0026thinsp;\u0026gt;\u0026thinsp;3 mm and the maximum inner diameter of the lumen\u0026thinsp;\u0026lt;\u0026thinsp;10 mm, with or without proximal intestinal dilation (\u0026gt;\u0026thinsp;25 mm), as the diagnostic criteria for narrowing\u003csup\u003e\u003cspan additionalcitationids=\"CR17\" citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eIntestinal Fistula: An abnormal communication between the intestinal lumen and the mesentery, other intra-abdominal hollow organs, the peritoneal cavity, or the skin\u003csup\u003e\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u003c/sup\u003e. On ultrasonography, it is characterized by disruption of the continuity of the intestinal wall, accompanied by a hypoechoic tubular structure adjacent to the bowel wall. The presence of intraluminal gas results in marked echogenicity. Demonstration of communication with the peritoneal cavity or abdominal organs is suggestive of an enterocutaneous fistula.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eAbscess: An irregular mass with thick walls, mixed echogenicity (liquid or liquid-containing), often located around an intestinal fistula. Sometimes, gas shadows may be visible inside, and posterior acoustic enhancement is commonly seen.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003c/ol\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\u003ch2\u003e2.4 Statistical Analysis\u003c/h2\u003e\u003cp\u003eAll data were analyzed using the SPSS 25.0(IBM Corp., Armonk, NY, USA) statistical analysis software. For continuous variables, data that followed a normal distribution were expressed as the mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\left(\\overline{\\text{X}}\\pm\\:\\text{S}\\right)\\)\u003c/span\u003e\u003c/span\u003e, while data that did not follow a normal distribution were expressed as the median (interquartile range) (P25, P75). Categorical variables were expressed as percentages. The consistency analysis of SICUS in diagnosing small bowel inflammatory lesions, complications, and surgical outcomes was performed using the kappa coefficient. A kappa value of \u0026lt;\u0026thinsp;0.2 indicates poor consistency; 0.2\u0026ndash;0.4 indicates fair consistency; 0.4\u0026ndash;0.6 indicates moderate consistency; 0.6\u0026ndash;0.8 indicates strong consistency; and 0.8\u0026ndash;1.0 indicates very strong consistency. The diagnostic performance of SICUS and MRE for SBID was compared using the McNemar test (paired chi-square test), and a P value of \u0026lt;\u0026thinsp;0.05 was considered statistically significant.\u003c/p\u003e\u003c/div\u003e"},{"header":"3. Results","content":"\u003cdiv id=\"Sec10\" class=\"Section2\"\u003e\u003ch2\u003e3.1 Patient Characteristics\u003c/h2\u003e\u003cp\u003eA total of 57 patients with pathologically confirmed inflammatory lesions were included in this study, comprising 36 males (63.2%) and 21 females (36.8%), with a mean age of 40.0\u0026thinsp;\u0026plusmn;\u0026thinsp;13.9 years. The predominant clinical manifestation was abdominal pain, observed in 51 patients (89.5%). Other symptoms included altered bowel habits in 14 (24.6%), diarrhea in 9 (15.8%), vomiting in 5 (8.8%), abdominal distension in 3 (5.3%), perianal lesions in 2 (3.5%), hematochezia in 2 (3.5%), fever in 2 (3.5%), and melena in 1 (1.8%) (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Postoperative pathological diagnoses confirmed inflammatory lesions in all 57 patients, including CD in 50 cases, nonspecific enteritis in 5, intestinal tuberculosis in 1, and cryptogenic multifocal ulcerous stenosing enteritis (CMUSE) in 1.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eDemographic and Clinical Characteristics of SBID (N\u0026thinsp;=\u0026thinsp;57)\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"3\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCharacteristic\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNumber of Cases (n)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003ePercentage (%)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSex\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMale\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e36\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e63.2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFemale\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e21\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e36.8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAge [years, \u0026oline;x\u0026thinsp;\u0026plusmn;\u0026thinsp;s]\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e40.0\u0026thinsp;\u0026plusmn;\u0026thinsp;13.9\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eClinical manifestations\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAbdominal pain\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e51\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e85.9\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAltered bowel habits\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e24.6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDiarrhea\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e15.8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVomiting\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e8.8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAbdominal distension\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e5.3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePerianal lesions\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e3.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHematochezia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e3.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFever\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e3.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMelena\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e1.8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\u003ch2\u003e3.2 Diagnostic Consistency of SICUS With Surgical Findings in SBID Complications\u003c/h2\u003e\u003cp\u003eAmong the 57 patients with surgically confirmed small bowel inflammatory lesions, 54 presented with strictures, 29 with enteric fistulas, and 11 with abscesses. For strictures, SICUS demonstrated a sensitivity of 87.0% (95% CI: 75.2\u0026ndash;94.3) and a specificity of 100% (95% CI: 29.2\u0026ndash;100), showing moderate agreement with surgical findings (κ\u0026thinsp;=\u0026thinsp;0.41). For enteric fistulas\u0026mdash;including 24 enteroenteric, 2 enterovesical, and 3 complex fistulas\u0026mdash;SICUS achieved a sensitivity of 82.8% (95% CI: 68.4\u0026ndash;97.1) and a specificity of 100% (95% CI: 88.4\u0026ndash;100), revealing strong agreement with surgical localization (κ\u0026thinsp;=\u0026thinsp;0.83). For abscesses\u0026mdash;4 located posterior to the ileocecal region, 5 in the right lower abdominal/pelvic mesentery, and 2 pelvic abscesses associated with enterovesical fistulas\u0026mdash;SICUS yielded a sensitivity of 81.8% (95% CI: 59.7\u0026ndash;100) and a specificity of 100% (95% CI: 92.3\u0026ndash;100), demonstrating excellent agreement with surgical findings (κ\u0026thinsp;=\u0026thinsp;0.88).(Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e\u003cb\u003e)\u003c/b\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eDiagnostic performance of SICUS for SBID-related complications compared with surgical findings (N\u0026thinsp;=\u0026thinsp;57)\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"10\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eComplication\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eIntraoperative Diagnosis\u003c/p\u003e\u003cp\u003e(n)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eTrue\u003c/p\u003e\u003cp\u003ePositive\u003c/p\u003e\u003cp\u003e(n)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eFalse\u003c/p\u003e\u003cp\u003ePositive\u003c/p\u003e\u003cp\u003e(n)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eFalse\u003c/p\u003e\u003cp\u003eNegative\u003c/p\u003e\u003cp\u003e(n)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eTrue\u003c/p\u003e\u003cp\u003eNegative\u003c/p\u003e\u003cp\u003e(n)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eSensitivity\u003c/p\u003e\u003cp\u003e(%)\u003c/p\u003e\u003cp\u003e(95% CI)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e\u003cp\u003eSpecificity\u003c/p\u003e\u003cp\u003e(%)\u003c/p\u003e\u003cp\u003e(95% CI)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c9\"\u003e\u003cp\u003eAccuracy\u003c/p\u003e\u003cp\u003e(%)\u003c/p\u003e\u003cp\u003e(95% CI)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c10\"\u003e\u003cp\u003eKappa Coefficient\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003estenosis\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e54\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e47\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e87.0(75.2,94.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e100(29.2,100)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e87.7(76.3,94.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e\u003cp\u003e0.41\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003efistulas\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e24\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e82.8(68.4,97.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e100(88.4,100)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e91.2(80.7,97.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e\u003cp\u003e0.83\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eabscesses\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e46\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e81.8(59.7,100)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e100(92.3,100)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e96.5(90.1,100)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e\u003cp\u003e0.88\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec12\" class=\"Section2\"\u003e\u003ch2\u003e3.3 Diagnostic Performance of SICUS in SBID and SBID Complications\u003c/h2\u003e\u003cp\u003eSICUS demonstrated a positive detection rate of 96.5% (55/57) for SBID, identical to that of MRE (96.5%). For complications, the sensitivity of SICUS was 87.0% (95% CI: 75.2\u0026ndash;94.3) for strictures, 82.8% (95% CI: 68.4\u0026ndash;97.1) for enteric fistulas, and 81.8% (95% CI: 59.7\u0026ndash;100.0) for abscesses, with a specificity of 100% for all. Compared with MRE, SICUS showed numerically higher sensitivity for detecting strictures (87.0% vs 83.3%) and fistulas (82.8% vs 65.5%). However, McNemar\u0026rsquo;s test revealed no statistically significant differences between SICUS and MRE in the diagnosis of strictures (P\u0026thinsp;=\u0026thinsp;0.803), fistulas (P\u0026thinsp;=\u0026thinsp;0.301), or abscesses (P\u0026thinsp;=\u0026thinsp;0.480) (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e2\u003c/span\u003e\u003cb\u003e)\u003c/b\u003e. Thus, although SICUS exhibited slightly higher sensitivity values for certain complications, these differences were attributable to random sampling variation rather than true differences in diagnostic efficacy. Overall, no significant difference was observed between the two modalities in the diagnosis of SBID (P\u0026thinsp;=\u0026thinsp;1.00). (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e3\u003c/span\u003e\u003cb\u003e)\u003c/b\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eSensitivity, specificity, and accuracy of SICUS versus MRE in detecting SBID-related complications (N\u0026thinsp;=\u0026thinsp;57)\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"11\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eComplication\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eIntraoperative Diagnosis\u003c/p\u003e\u003cp\u003e(n)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eImaging\u003c/p\u003e\u003cp\u003eModality\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eTrue\u003c/p\u003e\u003cp\u003ePositive\u003c/p\u003e\u003cp\u003e(n)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eFalse\u003c/p\u003e\u003cp\u003ePositive\u003c/p\u003e\u003cp\u003e(n)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eFalse\u003c/p\u003e\u003cp\u003eNegative\u003c/p\u003e\u003cp\u003e(n)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eTrue\u003c/p\u003e\u003cp\u003eNegative\u003c/p\u003e\u003cp\u003e(n)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e\u003cp\u003eSensitivity\u003c/p\u003e\u003cp\u003e(%)\u003c/p\u003e\u003cp\u003e(95% CI)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c9\"\u003e\u003cp\u003eSpecificity\u003c/p\u003e\u003cp\u003e(%)\u003c/p\u003e\u003cp\u003e(95% CI)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c10\"\u003e\u003cp\u003eAccuracy\u003c/p\u003e\u003cp\u003e(%)\u003c/p\u003e\u003cp\u003e(95% CI)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c11\"\u003e\u003cp\u003eP value vs. MRE (McNemar\u0026rsquo;s test)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003estenosis\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e54\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eSICUS\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e47\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e87.0\u003c/p\u003e\u003cp\u003e(75.2,94.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e100\u003c/p\u003e\u003cp\u003e(29.2,100)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e87.7\u003c/p\u003e\u003cp\u003e(76.3,94.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e0.803 (sensitivity difference)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMRE\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e83.3\u003c/p\u003e\u003cp\u003e(71.1,91.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e100\u003c/p\u003e\u003cp\u003e(29.2,100)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e84.2\u003c/p\u003e\u003cp\u003e(72.4,92.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003efistulas\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eSICUS\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e24\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e82.8\u003c/p\u003e\u003cp\u003e(68.4,97.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e100\u003c/p\u003e\u003cp\u003e(88.4,100)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e91.2\u003c/p\u003e\u003cp\u003e(80.7,97.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e0.301\u003c/p\u003e\u003cp\u003e(sensitivity difference)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMRE\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e19\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e65.5\u003c/p\u003e\u003cp\u003e(45.7,82.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e100\u003c/p\u003e\u003cp\u003e(88.4,100)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e82.5\u003c/p\u003e\u003cp\u003e(70.6,90.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eabscesses\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eSICUS\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e46\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e81.8\u003c/p\u003e\u003cp\u003e(59.7,100)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e100\u003c/p\u003e\u003cp\u003e(92.3,100)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e96.5\u003c/p\u003e\u003cp\u003e(90.1,100)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e0.480\u003c/p\u003e\u003cp\u003e(sensitivity difference)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMRE\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e81.8\u003c/p\u003e\u003cp\u003e(59.7,100)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e97.8\u003c/p\u003e\u003cp\u003e(90.5,100)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e94.7\u003c/p\u003e\u003cp\u003e(87.9,98.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e"},{"header":"4. Discussion","content":"\u003cp\u003eSIBD presents with a broad spectrum of nonspecific clinical symptoms, including abdominal pain, diarrhea, gastrointestinal bleeding, bloating, and weight loss\u003csup\u003e\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u003c/sup\u003e. In our study, abdominal pain was the most common manifestation (89.5%), followed by altered bowel habits (24.6%). Due to the limited visualization of the entire small intestine by conventional endoscopy, these nonspecific symptoms frequently lead to misdiagnosis or missed diagnosis. Therefore, SIBD should be considered in patients with recurrent, unexplained gastrointestinal complaints despite negative findings on routine endoscopy.\u003c/p\u003e\u003cp\u003eIn this context, oral 2.5% mannitol SICUS demonstrated substantial diagnostic value, with a positivity rate of 96.5% in identifying SIBD. By effectively distending the small intestine and minimizing gas interference, SICUS enables clear visualization of intestinal structures and lesions\u003csup\u003e\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u003c/sup\u003e. Moreover, it allows dynamic assessment of bowel wall morphology and peristalsis, enhancing the detection of stenotic and rigid segments\u0026mdash;particularly during the \"peak effect\" phase\u0026mdash;thus reducing false positives. In our study, SICUS showed a sensitivity of 87.0% (95% CI: 75.2\u0026ndash;94.3) for detecting stenosis, slightly higher than that of MRE (83.3%; 95% CI: 71.1\u0026ndash;91.5). For fistulas, its real-time scanning capability allowed direct visualization of contrast flow\u003csup\u003e\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u003c/sup\u003e, resulting in higher sensitivity (82.8%; 95% CI: 68.4\u0026ndash;97.1) compared to MRE (65.5%; 95% CI: 45.7\u0026ndash;82.1), with strong concordance with surgical findings (κ\u0026thinsp;=\u0026thinsp;0.83). In detecting abscesses, SICUS provided a superior acoustic window due to improved bowel preparation and distension\u003csup\u003e\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e\u003c/sup\u003e, achieving diagnostic performance comparable to MRE, with no statistically significant difference (P\u0026thinsp;\u0026gt;\u0026thinsp;0.05).\u003c/p\u003e\u003cp\u003eImportantly, paired statistical analysis using the McNemar test confirmed that there were no significant differences in diagnostic efficacy between SICUS and MRE for SIBD complications (all P\u0026thinsp;\u0026gt;\u0026thinsp;0.05). Nevertheless, SICUS demonstrated distinct clinical advantages. First, as a noninvasive and radiation-free technique, its per-examination cost is approximately one-fifth that of MRE, making it particularly suitable for patients requiring repeated follow-up, such as those undergoing remission monitoring for CD. Second, SICUS enables real-time dynamic observation of intestinal peristalsis, providing a more intuitive assessment of proximal dilatation secondary to stricture. Although this advantage did not yield a statistically significant difference (P\u0026thinsp;=\u0026thinsp;0.803), it remains clinically meaningful, especially in primary care settings where MRE accessibility is limited.\u003c/p\u003e\u003cp\u003eIn this study, both SICUS and MRE demonstrated high diagnostic performance for SIBD, each achieving a positive detection rate of 96.5%. The few missed cases may be attributable to examinations conducted during remission phases. Compared with previous studies, such as Zhu et al. (88.3%)\u003csup\u003e21\u003c/sup\u003e, the higher diagnostic yield observed here may be explained by the use of surgical confirmation as the reference standard and by the advanced expertise of our gastrointestinal ultrasonography specialists \u003csup\u003e\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e,\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eThis study has several strengths and novel aspects. Firstly, surgical pathology was used as the gold standard, providing objective validation of imaging findings. Secondly, by focusing on patients with confirmed and complicated SBID, it offered valuable insights into the performance of SICUS in severe cases. Thridly, all examinations were performed by an experienced specialist, which ensured high image quality and diagnostic accuracy. Fourthly, the study specifically evaluated the capacity of SICUS to detect complications such as strictures and fistulas, highlighting its clinical utility.\u003c/p\u003e\u003cp\u003eNonetheless, several limitations should be acknowledged. This was a single-center study with a relatively small sample size, which may restrict the generalizability of the findings. The use of surgical results as the gold standard may have introduced selection bias and potentially led to an overestimation of diagnostic performance. Although the SICUS examinations were conducted by two experienced physicians, inter-operator agreement was not formally assessed. Furthermore, the small subgroup sample for abscesses (n\u0026thinsp;=\u0026thinsp;11) may have resulted in limited statistical power and underestimation of potential differences between modalities. Future studies should therefore include large-scale, multicenter cohorts and formal inter-operator consistency assessments to further validate the diagnostic efficacy of SICUS and clarify subtle differences compared with MRE.\u003c/p\u003e"},{"header":"5. Conclusions","content":"\u003cp\u003eSICUS is a noninvasive, radiation-free, cost-effective, and well-tolerated technique for the evaluation of SBID. It demonstrates high diagnostic sensitivity and accuracy for SIBD and its complications, with particular advantages in detecting strictures and fistulas. Although its overall diagnostic performance was not statistically superior to MRE (P\u0026thinsp;\u0026gt;\u0026thinsp;0.05), SICUS offers distinct clinical advantages, including real-time dynamic assessment, low cost, and wide accessibility. These features make SICUS a valuable alternative to MRE, particularly for patients requiring repeated follow-up or in primary healthcare settings, thereby facilitating the early diagnosis and management of SIBD.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAuthor contributions:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAhuang Cai: Conceptualization, Formal Analysis, Investigation, Methodology, Software, Writing – original draft. Yu Xu: Formal Analysis,Data curation, Investigation, Funding acquisition, Writing – original draft. Liqin Yu:Formal Analysis, Data curation, Investigation, Writing – original draft. Hailan Chen: Acquisition, analysis, or interpretation of data. Yan Chen: Acquisition, analysis, or interpretation of data. Shengnan Wu: Acquisition, analysis, or interpretation of data. Xuan Wang: Acquisition, analysis, or interpretation of data. Linglin Wei: Methodology, Project administration, Writing – review and editing. Xinxiu Liu: Conceptualization, Project administration, Resources, Supervision, Validation, Writing – review and editing.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding Statement:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that financial support was received for the research and/or publication of this article. This study was supported by Fujian Medical University QiHang Fund [grant no. 2022QH1093].\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability statement:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe original contributions presented in this study are included in this article/Supplementary material, further inquiries can be directed to the corresponding author.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eRefeEthics statement:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was in accordance with the Ethical Standards of the Institutional Ethics Committee of First Affiliated Hospital of Fujian Medical University and with the 1964 Helsinki declaration and its later amendments or comparable Ethical Standards. Ethics batch number: IEC-FOM-013-2.0. As a purely retrospective review of medical records that did not involve any personally identifiable information, the requirement for informed consent was waived.rences\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eIRB approval status:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was approved by The Ethics Committee of the First Affiliated Hospital of Fujian Medical University (IRB [2020]190).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePatient Consent to Publish:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe requirement for informed patient consent was waived because of the anonymous nature of the data.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll authors have no conflicts of interest that are directly relevant to the content of this article.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eDanese S, Fiocchi C. Ulcerative colitis. 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J Ultrasound. 2017;20(1):1\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePallotta N, Vincoli G, Montesani C, Chirletti P, Pronio A, Caronna R, Ciccantelli B, Romeo E, Marcheggiano A, Corazziari E. Small intestine contrast ultrasonography (SICUS) for the detection of small bowel complications in crohn's disease: a prospective comparative study versus intraoperative findings. Inflamm Bowel Dis. 2012;18(1):74\u0026ndash;84.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eAllocca M, Fiorino G, Bonifacio C, et al. Comparative Accuracy of Bowel Ultrasound Versus Magnetic Resonance Enterography in Combination With Colonoscopy in Assessing Crohn's Disease and Guiding Clinical Decision-making. J Crohns Colitis. 2018;12(11):1280\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"small bowel inflammatory disorders, Small Intestine Contrast Ultrasound, Magnetic Resonance Enterography, mannitol, diagnosis","lastPublishedDoi":"10.21203/rs.3.rs-7537453/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7537453/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eObjective\u003c/h2\u003e\u003cp\u003eThis study aimed to evaluate the diagnostic performance of Small Intestine Contrast Ultrasound (SICUS) with oral 2.5% mannitol in detecting small bowel inflammatory disease (SBID), and to compare its efficacy with that of Magnetic Resonance Enterography (MRE).\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e\u003cp\u003eA retrospective analysis was conducted in 57 patients with pathologically confirmed SBID who underwent both SICUS and MRE prior to surgery. The sensitivity, specificity, and concordance with surgical findings were calculated for each modality in diagnosing SBID and its complications, including strictures, fistulas, and abscesses.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eBoth SICUS and MRE achieved a detection rate of 96.5% for SBID. SICUS showed higher sensitivity than MRE for identifying strictures (87.0% vs. 83.3%) and fistulas (82.8% vs. 65.5%), with strong consistency with surgical findings (κ\u0026thinsp;=\u0026thinsp;0.83 for fistulas). For detecting abscesses, the sensitivity was 81.8% for both modalities. Notably, SICUS achieved 100% specificity for all complications. Additional advantages of SICUS include real-time dynamic evaluation, high spatial resolution, reduced interference from intestinal gas, and greater accessibility in primary care settings.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e\u003cp\u003eSICUS is a reliable, non-invasive, and cost-effective imaging technique for evaluating SBID and its complications. It provides diagnostic performance comparable to or exceeding that of MRE, particularly for strictures and fistulas. Given its repeatability and suitability for patients unable to undergo MRE, SICUS represents a practical alternative in clinical practice.\u003c/p\u003e","manuscriptTitle":"Oral 2.5% mannitol Small Intestine Contrast Ultrasound for small bowel inflammatory disease: A Surgical-Validated Comparative Study with Magnetic Resonance Enterography","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-09-26 15:05:05","doi":"10.21203/rs.3.rs-7537453/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"0d2f374d-78b5-4242-966f-b28b4d840b12","owner":[],"postedDate":"September 26th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-01-27T05:24:35+00:00","versionOfRecord":[],"versionCreatedAt":"2025-09-26 15:05:05","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7537453","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7537453","identity":"rs-7537453","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}