Computed Tomography Scan Predictors of Intestinal Necrosis in Strangulated Small-Bowel Obstruction: A Retrospective Cohort Study

Computed Tomography Scan Predictors of Intestinal Necrosis in Strangulated Small-Bowel Obstruction: A Retrospective Cohort Study | 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 Article Computed Tomography Scan Predictors of Intestinal Necrosis in Strangulated Small-Bowel Obstruction: A Retrospective Cohort Study Toshiyuki Suzuki, Akiyo Matsumoto, Daisuke Sugiki, Takahiko Akao, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6302611/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 24 Jul, 2025 Read the published version in Scientific Reports → Version 1 posted 10 You are reading this latest preprint version Abstract The preoperative diagnosis of intestinal necrosis in strangulated small - bowel obstruction (SBO) is clinically important because it is prognostically relevant. The current study assessed the predictors of preoperative intestinal necrosis in strangulated SBO. This retrospective single-center study included 75 consecutive patients undergoing surgery for strangulated SBO. Patients with inguinal, femoral, and obturator hernia were excluded from the analysis. The computed tomography (CT) scan value of the strangulated bowel was calculated as the average of the CT scan values ​​of the bowel contents measured at three different random points. The patients were divided into the intestinal necrosis and without necrosis groups. Clinical and CT scan findings were retrospectively analyzed, and univariate and multivariate analyses were performed. The cutoff CT scan value was the mean value. In total, 37 patients presented with intestinal necrosis in the strangulated SBO and 38 did not. In the univariate analysis, a CT scan value ≥ 20 HU for strangulated SBO, massive ascites, and mesenteric fluid were significant predictors of preoperative bowel necrosis in strangulated SBO. These factors were also independent predictors of preoperative intestinal necrosis in strangulated SBO in the multivariate analysis. Thus, these factors may help in predicting and managing necrosis in strangulated SBO. Health sciences/Diseases Health sciences/Medical research CT value ascites mesenteric fluid strangulated small-bowel obstruction CT findings Figures Figure 1 Figure 2 Introduction Strangulated small-bowel obstruction (SBO) is a type of bowel obstruction associated with ischemia of the intestinal tract. SBO requires timely treatment as it can cause intestinal necrosis if left untreated and can be fatal if it progresses to peritonitis from perforation [ 1 – 3 ]. Strangulated SBO can be classified into two: with and without intestinal necrosis. This was believed to be attributed to the degree of strangulation. Strangulated SBO is caused by decreased blood supply to the digestive tract. Based on the severity and duration of ischemia, lesions can range from patchy mucosal necrosis to transmural intestinal necrosis [ 4 ]. Therefore, if a patient is diagnosed with bowel necrosis and surgery is performed before intestinal necrosis occurs, bowel resection can be avoided by simply releasing strangulation. However, over time, bowel necrosis may lead to unavoidable bowel resection, which can result in complications such as anastomotic leakage and stenosis. Therefore, the preoperative diagnosis of bowel necrosis in strangulated SBO is clinically important because of its prognostic relevance. Strangulated SBO is often diagnosed via computed tomography (CT) scan, a key diagnostic tool. The findings include closed loop, ascites, mesenteric fluid, and small-bowel wall thickening [5 6]. Regarding the early diagnosis of strangulated SBO, several reports have shown that CT scan is useful [ 7 – 15 ]. However, only a few studies have discussed the differences in the preoperative CT scan findings of necrosis in strangulated SBO. Patients do not always visit a hospital before necrosis develops, and there have been cases in which the diagnosis was not made immediately. However, the patient was monitored and then underwent surgery, which lead to necrosis. Therefore, the prediction of bowel necrosis in strangulated SBO can be challenging. Identifying patients at risk for bowel necrosis in strangulated SBO prior to surgery can lead to the case-by-case modification of surgical technique and postoperative management. Moreover, it may lead to improved postoperative outcomes. Therefore, the current study aimed to assess the predictors of preoperative bowel necrosis in strangulated SBO. Methods Patients and data collection In total, 75 consecutive patients underwent surgery for strangulated SBO between January 1, 2012, and March 31, 2024. The diagnosis of SBO can be easily based on physical and CT findings. Thus, patients diagnosed with inguinal, femoral, and obturator hernia and those who only presented with large-bowel strangulation, which was caused by tumors or torsion and colon resection, were excluded from the analysis. The patients were divided into two groups: those with bowel necrosis who underwent bowel resection and those with strangulation release only, not bowel necrosis. Intestinal necrosis was determined based on intraoperative dark-red or black coloration of the strangulated intestine and cessation of peristalsis and blood flow in the strangulated intestine. A gastrointestinal surgeon determined the presence of intestinal necrosis, and intestinal resection was performed. Histopathological analysis of the resected specimens revealed necrotic tissues in all cases. In addition, the without necrosis group did not present with postoperative complications such as perforation and stenosis. This study was performed in accordance with the principles of the Declaration of Helsinki and was approved by the Joint Ethics Review Committee of the Tokushukai Group (TGE01762-011). The need for informed consent was waived due to the retrospective nature of the study. CT scan findings Figure 1 shows an image of the strangulated SBO. Closed loop was defined as the intestinal tract strangulated by the band. The CT scan value in the strangulated intestinal tract was defined as the average CT scan values of the intestinal contents (closed loop) measured at three random points on simple abdominal CT scan (Figs. 2 a, 2 b, 2 c, and 2 d). The CT scan image was magnified, and caution was taken not to include the intestinal wall. A CT scan value ≥ 20 should specify Hounsfield Units (HU) consistently. Massive ascites was defined as ascites in two or more sites (the pelvis and around the liver and spleen) on simple CT scan (Figs. 2 e, 2 f). Patients with a strangulated intestine with mesenteric fluid were diagnosed with mesenteric fluid (+) (Figs. 2 g, 2 h). One investigator (T.S.) performed all CT scan finding analyses under the supervision of an experienced radiologist. The CT scan examinations were performed using one of the hospital’s two multidetector CT scanners (Siemens Definition AS 64-channel and Siemens Definition Flash 128-channel). The scanning parameter was 120 kVp, and the dose was automatic. An 2-mm axial-slice thickness was acquired from the hepatic dome to the pubic symphysis. Images were sent to the Picture Archiving and Communication System (YOKOGAWA, FujiFilm Corporation). Statistical analysis The demographic characteristics and preoperative CT scan findings of the necrosis and without necrosis groups were compared. Categorical variables were presented as numbers with percentages and compared using the chi-square test. Continuous variables were expressed as medians with ranges and compared using the Mann–Whitney U test. Univariate and multivariate analyses of the predictive factors of bowel necrosis were performed via a logistic regression analysis. Variables that were significant in the univariate analysis were included in the multivariate analysis. To confirm multicollinearity, the variance inflation factor (VIF) of these factors was calculated. If the VIF was close to 1, there was no multicollinearity issue. If there was a term with a large VIF (use of ≥ 5 as a criterion), then the multicollinearity was strong. The cutoff value for intestinal CT scan values was 20 HU. This was because the mean CT scan value in the necrotic group was 19.5. The cutoff values for other continuous variables were also determined using the mean values of the factors. A two-sided P value of < 0.05 indicated statistically significant differences. All statistical analyses were performed using JMP version 12 (SAS Institute, Cary, NC, the USA). Results Clinical characteristics of the participants Of the 75 patients, 37 (49%) had intestinal necrosis. Table 1 shows the differences in the clinical characteristics between patients with necrosis and those without. Patients with necrosis had a higher white blood cell (WBC) count (12610/µL vs. 10540/µL, P = 0.031) than those without necrosis. There were no differences in the proportion of patients who underwent abdominal surgery between the necrosis and without necrosis groups. Regarding the CT scan findings, patients with necrosis had a higher CT scan value for strangulated SBO (17.2 vs. 8.1 HU, P < 0.001), a higher massive ascites ratio (84% vs. 42%, P < 0.001), and a greater mesenteric fluid ratio (65% vs. 13%, P < 0.001) than those without necrosis. Table 1 Clinical characteristics between patients with necrosis and those without. Variables Necrosis group (n = 37) Non-necrosis group (n = 38) P value Characteristics of the patients Sex, male/female 15 (41%)/22 (59%) 15 (39%)/23 (61%) 0.924 Age, years 80 [26 − 92] 71 [30 − 96] 0.120 Abdominal surgery 21/37 (57%) 28/38 (74%) 0.123 WBC count, µL 12.6 × 10³ [3.5 × 10³−31.4 × 10³] 10.5 × 10³ [3.5 × 10³−21.6 × 10³] 0.031 CRP level, mg/dL 0.99 [0.01 − 26.9] 0.24 [0.02 − 28.4] 0.109 CT scan findings CT scan value for strangulated SBO, HU 17.2 [5.1 − 62.1] 8.1 [2 − 27.3] < 0.001 Massive ascites 32/37 (84%) 16/38 (42%) < 0.001 Mesenteric fluid 24/37 (65%) 5/38 (13%) < 0.001 CRP, C-reactive protein; CT, computed tomography; SBO, small-bowel obstruction; WBC, white blood cell Univariate and Multivariate Risk Analysis of the Strangulated SBO with Necrosis The cutoff CT scan values for continuous variables were set at 20 HU in patients with strangulated SBO, and the cutoff WBC count was 13300 µL. As shown in Table 2 , the significant risk factors of strangulated SBO with necrosis in the univariate analysis were WBC count ≥ 13300 µL (odds ratio [OR]: 2.45, P = 0.07), CT scan value ≥ 20 HU for strangulated SBO (OR: 17.76, P < 0.001), massive ascites (OR: 8.8, P < 0.001), and mesenteric fluid (OR: 12.18, P < 0.001). In the multivariate analysis, the risk factors of strangulated SBO with necrosis were a CT value of ≥ 20 HU for strangulated SBO (OR: 73.51, 95% confidence interval [95% CI]: 9.35–1696.11, P < 0.001), massive ascites (OR: 4.76, 95% CI: 1.00–27.21, P = 0.049), and mesenteric fluid (OR: 21.99, 95% CI: 5.49–109.41, P < 0.001) (Table 3 ). The VIFs were 1.06 for a CT scan value ≥ 20 HU for strangulated SBO, 1.27 for massive ascites, and 1.28 for mesenteric fluid. There were no multicollinearity issues. Table 2 Strangulated small-bowel obstruction with necrosis based on the univariate predictive analysis Variables OR 95% CI P value Characteristics of the patients Sex (male) 1.04 0.41–2.64 0.92 Age 1.02 0.99–1.05 0.07 Abdominal surgery 0.46 0.17–1.22 0.12 WBC count ≥ 13,300 µL 2.45 0.92–6.82 0.70 CRP level 1.05 0.96–1.19 0.24 CT scan findings CT scan value ≥ 20 HU for strangulated SBO 17.76 3.19–333.78 < 0.001 Massive ascites 8.8 2.99–30.33 < 0.001 Mesenteric fluid 12.18 4.09–42.73 < 0.001 CI, confidence interval; CRP, C-reactive protein; CT, computed tomography; OR, odds ratio; SBO, small-bowel obstruction; WBC, white blood cell Table 3 Strangulated small-bowel obstruction with necrosis based on the multivariate predictive analysis Variables OR 95% CI P value CT scan value ≥ 20 HU for strangulated SBO 73.51 9.35–1696.11 < 0.001 Massive ascites 4.76 1.00–27.21 0.049 Mesenteric fluid 21.99 5.49–109.41 < 0.001 CI, confidence interval; CT, computed tomography; OR, odds ratio; SBO, small-bowel obstruction Discussion A CT scan value ≥ 20 HU for strangulated SBO, massive ascites, and mesenteric fluid were the independent predictive factors of strangulated SBO with necrosis. These findings are strongly suggestive of intestinal necrosis in strangulated bowel obstruction and are indicative of immediate treatment, (i.e., emergency surgery). In addition, the possibility of intestinal resection can be identified before surgery. For example, the use of appropriate surgical technique, blood transfusion preparation, and intensive care unit management can be discussed. Therefore, the bowel may have confirmed laparoscopically and resected. If a massive bowel resection is anticipated, the need for the blood transfusion preparation central venous catheter management may also be determined. Postoperative intensive care unit management is essential in cases requiring bowel resection, and it may be possible to prepare for it. Anticipating bowel resection preoperatively may improve prognosis by preparing for and promptly responding to postoperative management. Therefore, the CT scan values in the intestinal tract of patients with strangulated bowel obstruction should be measured, and massive ascites or mesenteric fluid must be identified. However, the decision to perform surgery must also be based on other clinical factors such as patient stability, comorbidities, and surgical risk assessments results, which may be helpful in the management of strangulated SBO when combined with CT scan findings. In addition, gastrointestinal surgeons must be trained to interpret the CT scan findings of strangulated SBO. We are training to identify the small intestine and closed loops of the intestine on CT scan images. At our hospital, we regularly hold study sessions for surgeons and radiologists on CT scan image interpretation to improve their reading skills. Moreover, the preoperative diagnoses and intraoperative findings are compared, and feedback is provided. Hence, the small intestines with strangulated ileus, massive ascites, and mesenteric fluid are easy to identify [ 16 ]. To the best of our knowledge, the current study first showed that a CT scan value ≥ 20 HU is an independent risk factor of strangulated SBO with necrosis. The CT scan values were ≥ 20 HU on a blood basis, which is in close agreement with our previous study results on CT values ≥ 24 HU in the appendiceal lumen in gangrenous appendicitis [ 17 ]. In strangulated SBO with necrosis, an increased intestinal tract pressure attributed to obstruction caused changes such as impaired blood flow in the intestinal tract, insufficient blood supply to the intestinal mucosa, and thrombus formation. This phenomenon results in mucosal necrosis and bleeding in the lumen. Further, in cases of strangulated SBO with necrosis, blood pools may be observed in some cavities of the resected specimens, which can cause high CT scan values in strangulated SBO with necrosis. Whether the observed CT scan values ​​are attributed solely to these mechanisms remains unclear. Therefore, further research should be performed. The CT scan values in strangulated SBO with necrosis are easy to obtain and should be measured aggressively. Previous studies have confirmed the discriminatory effect of CT scan findings, particularly massive ascites and the presence of mesenteric fluid, the diagnosis of SBO [ 14 , 18 – 21 ]. Our study had a similar result. In terms of mechanism, ascites and mesenteric fluid can be caused by the development of edematous thickening of the intestinal wall and mesentery owing to progressive congestion of the intestinal tract and mesentery with inadequate mesenteric circulation, leading to the leakage of large amounts of effluent and blood. Therefore, if the degree of strangulation is greater, the likelihood of finding large amounts of ascites or mesenteric fluid is higher, Therefore, the patient exhibited findings secondary to strangulation. CT angiography (CTA) is the gold standard for predicting bowel ischemia, with a sensitivity of 83–100% and specificity of 61–93% [ 12 ]. Further, decreased small-bowel wall contrast on CTA indicates intestinal ischemia [ 19 , 22 ]. However, in some patients with asthma, renal impairment, and hyperthyroidism, these tests cannot be performed because contrast agents are contraindicated [ 23 , 24 ]. In addition, CTA cannot be conducted due to the potential risk of iodine-induced nephropathy, high cost, and the unavailability of most primary health care providers [ 25 ]. The strength of this study is that it presented data that can help resolve all the above mentioned issues, which makes clinical sense. A simple CT scan is essential when diagnosing strangulated bowel obstruction, and there are cases in which contrast agents cannot be used because of the risks involved. However, based on the study results, the use of contrast agents might be reduced if strangulated bowel obstruction with necrosis is suspected based on simple CT scan findings alone. It is also useful from a health care economic point of view. This study did not compare CTA with simple CT. Thus, the findings may be speculative. However, we hope to include them in future studies. The current study had several limitations that should be acknowledged. First, this was a retrospective, single-center study with a small sample size. Therefore, patient bias might have existed. To address this, further prospective multicenter studies must be conducted by dedicated associations and rigorous and high-volume tertiary centers to establish reliable evidence-based medicine guidelines. Therefore, it must be recognized that this study was strongly exploratory in nature. Second, there were no clear criteria for determining bowel necrosis. The judgment of intraoperative surgeons was used to determine bowel necrosis. Intestinal necrosis was identified based on the color of the intestine and the cessation of intestinal peristalsis, but it was challenging to establish objective criteria. Nevertheless, there were no complications associated with postoperative bowel necrosis in the without necrosis group. Further, all pathology results of the necrosis group showed necrosis. Conclusion CT scan value ​​≥20 HU, high-volume ascites, and mesenteric fluid can be independent predictors of intestinal necrosis in strangulated SBO. However, it must be recognized that these findings are based on single-center retrospective studies with small sample sizes. Therefore, the additional application of CT scan findings may be useful in predicting and managing of necrosis in strangulated SBO. Declarations Acknowledgments The authors want to thank Saki Kasuya (Medical Affairs Division Medical Information Management Office, Hanyu General Hospital Medical History Department) and Minami Kawakita (Medical Affairs Division Medical Information Management Office, Hanyu General Hospital Medical History Department) for their assistance in collecting the medical data. Author contributions Toshiyuki Suzuki: Conceptualization, Methodology, Software, Validation, Formal analysis, Investigation, Resources, Writing–Original draft, Visualization, Project administration, Funding acquisition. Akiyo Matsumoto: Data curation, Supervision. Daisuke Sugiki: Data curation, Supervision. Takahiko Akao: Data curation. Hiroshi Matsumoto: Writing–Review & editing. All authors approved the final version of the manuscript and agree to be held accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. Competing Interest Statement The authors have no competing interests to declare that are relevant to the content of this article. Data availability statement The datasets used and/or analyzed in the current study are available from the corresponding author upon reasonable request. Funding This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. Ethics approval This study was performed in accordance with the principles of the Declaration of Helsinki and was approved by the Joint Ethics Review Committee of the Tokushukai Group (TGE01762-011). The need for informed consent was waived due to the retrospective nature of this study. Consent to participate The need for informed consent was waived due to the retrospective nature of the study. Consent to publish The authors confirm that the participants provided informed consent for the publication of the images in Figure 2. References Megibow, A. J. Bowel obstruction. Evaluation with CT. Radiol. Clin. North. Am. 32 , 861–870 (1994). Bass, K. N., Jones, B. & Bulkley, G. B. Current management of small-bowel obstruction. Adv. Surg. 31 , 1–34 (1997). Bizer, L. S., Liebling, R. W., Delany, H. M. & Gliedman, M. L. Small bowel obstruction: the role of nonoperative treatment in simple intestinal obstruction and predictive criteria for strangulation obstruction. Surgery 89 , 407–413 (1981). Mitsudo, S. & Brandt, L. J. Pathology of intestinal ischemia. Surg. Clin. North. Am. 72 , 43–63 (1992). Rha, S. E. et al. CT and MR imaging findings of bowel ischemia from various primary causes. Radiographics 20 , 29–42 (2000 Jan). Taourel, P. et al. 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Tsushima, Y. et al. Safe use of iodinated and gadolinium-based contrast media in current practice in Japan: a questionnaire survey. Jpn J. Radiol. 34 , 130–139 (2016). Nijssen, E. C. et al. Prophylactic hydration to protect renal function from intravascular iodinated contrast material in patients at high risk of contrast-induced nephropathy (AMACING): a prospective, randomised, phase 3, controlled, open-label, non-inferiority trial. Lancet 389 , 1312–1322 (2017). Additional Declarations No competing interests reported. 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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-6302611","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":436294942,"identity":"164b383c-19ab-4b1e-8195-02026d83716b","order_by":0,"name":"Toshiyuki Suzuki","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABA0lEQVRIie2RMUsDMRTH3xG4Wx5kfQf9EJFAtCDtV8lx0Kl0KYiDSKd0Ubtev4Xg6pCjkMnqqpO63HwuUkHECHZrOLqJ5Df9CfmR938BiET+Lho5sz+B9PaIhe7iVsmN3lMB4fRv6mIIWZN/mFFPOlRte3Y04Xxt4e0WssPgK6goN2NUDuWycjTNq4lOqgZYfxZUUjowp6ieLyTzubh+RMHQAhM2pGQNFV6RBiX7/PLKw12XAopqP5hIvZIYr9hxh7JC2Z/dj5BcOk0ur6hY+i51ZSnYJZvPX582J+WQG3YDm/fzYsHX9Utrj8vQxnb9GIIfiUoRUnb38wz2USKRSORf8w19fE4WIXjOSQAAAABJRU5ErkJggg==","orcid":"","institution":"Hanyu General Hospital","correspondingAuthor":true,"prefix":"","firstName":"Toshiyuki","middleName":"","lastName":"Suzuki","suffix":""},{"id":436294943,"identity":"7b1e7775-9ad9-470d-b52d-7d4c488548a5","order_by":1,"name":"Akiyo Matsumoto","email":"","orcid":"","institution":"Hanyu General Hospital","correspondingAuthor":false,"prefix":"","firstName":"Akiyo","middleName":"","lastName":"Matsumoto","suffix":""},{"id":436294944,"identity":"c30f609e-1028-46b5-b0ec-fa8c6f38282a","order_by":2,"name":"Daisuke Sugiki","email":"","orcid":"","institution":"Dokkyo Medical University Saitama Medical Center","correspondingAuthor":false,"prefix":"","firstName":"Daisuke","middleName":"","lastName":"Sugiki","suffix":""},{"id":436294945,"identity":"d6a757ff-70be-451a-9340-f7188df6224d","order_by":3,"name":"Takahiko Akao","email":"","orcid":"","institution":"Hanyu General Hospital","correspondingAuthor":false,"prefix":"","firstName":"Takahiko","middleName":"","lastName":"Akao","suffix":""},{"id":436294946,"identity":"9dd06b49-2488-4f0b-8238-8aaa9131f8fb","order_by":4,"name":"Hiroshi Matsumoto","email":"","orcid":"","institution":"Hanyu General Hospital","correspondingAuthor":false,"prefix":"","firstName":"Hiroshi","middleName":"","lastName":"Matsumoto","suffix":""}],"badges":[],"createdAt":"2025-03-25 10:08:18","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6302611/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6302611/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1038/s41598-025-13186-x","type":"published","date":"2025-07-24T15:58:08+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":79830895,"identity":"7e3fda04-7f05-40e4-893e-06c6476567ae","added_by":"auto","created_at":"2025-04-03 10:29:14","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":639339,"visible":true,"origin":"","legend":"\u003cp\u003eImage of the strangulated small-bowel obstruction\u003c/p\u003e\n\u003cp\u003eClosed loop was defined as an intestinal loop constricted at two adjacent points with two\u003c/p\u003e\n\u003cp\u003ecollapsed small intestines nearby or one collapsed small intestine and the starting point\u003c/p\u003e\n\u003cp\u003eof a simple obstruction.\u003c/p\u003e","description":"","filename":"Fig.1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6302611/v1/73df0761448b472203113f97.jpg"},{"id":79830898,"identity":"35f0a0cf-e405-47eb-a0a1-29c662381fa4","added_by":"auto","created_at":"2025-04-03 10:29:14","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":729791,"visible":true,"origin":"","legend":"\u003cp\u003eComputed tomography scan findings\u003c/p\u003e\n\u003cp\u003e(a), (b) Strangulated small-bowel obstruction (SBO) without necrosis. The CT scan value for the strangulated intestinal tract was defined as the average of the CT scan values of the intestinal contents (closed loop) measured at three different points on simple abdominal CT scan. The CT scan value = 5.0 HU (5.3 + 6.0 + 3.8/3).\u003c/p\u003e\n\u003cp\u003e(c), (d) SBO with necrosis. The CT scan value = 26.6 HU (28.5 + 23.4 + 27.8/3).\u003c/p\u003e\n\u003cp\u003e(e) SBOwith necrosis. Ascites around the liver (white arrow) and spleen (yellow arrow).\u003c/p\u003e\n\u003cp\u003e(f) SBOwith necrosis. Ascites in the pelvis (yellow-green arrow).\u003c/p\u003e\n\u003cp\u003e(g) SBOwith necrosis. Mesenteric fluid (+) (yellow circle).\u003c/p\u003e\n\u003cp\u003e(h) SBO without necrosis. Mesenteric fluid (–) (blue circle).\u003c/p\u003e","description":"","filename":"Fig.2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6302611/v1/f8b520eae4ba5939b9732279.jpg"},{"id":87756873,"identity":"4fd9e065-5c81-4377-a3a2-91765b994e66","added_by":"auto","created_at":"2025-07-28 16:10:01","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2066096,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6302611/v1/1215b82c-d577-44bd-9bbd-1c2785d76427.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Computed Tomography Scan Predictors of Intestinal Necrosis in Strangulated Small-Bowel Obstruction: A Retrospective Cohort Study","fulltext":[{"header":"Introduction","content":"\u003cp\u003eStrangulated small-bowel obstruction (SBO) is a type of bowel obstruction associated with ischemia of the intestinal tract. SBO requires timely treatment as it can cause intestinal necrosis if left untreated and can be fatal if it progresses to peritonitis from perforation [\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Strangulated SBO can be classified into two: with and without intestinal necrosis. This was believed to be attributed to the degree of strangulation. Strangulated SBO is caused by decreased blood supply to the digestive tract. Based on the severity and duration of ischemia, lesions can range from patchy mucosal necrosis to transmural intestinal necrosis [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Therefore, if a patient is diagnosed with bowel necrosis and surgery is performed before intestinal necrosis occurs, bowel resection can be avoided by simply releasing strangulation. However, over time, bowel necrosis may lead to unavoidable bowel resection, which can result in complications such as anastomotic leakage and stenosis. Therefore, the preoperative diagnosis of bowel necrosis in strangulated SBO is clinically important because of its prognostic relevance.\u003c/p\u003e \u003cp\u003eStrangulated SBO is often diagnosed via computed tomography (CT) scan, a key diagnostic tool. The findings include closed loop, ascites, mesenteric fluid, and small-bowel wall thickening [5 6]. Regarding the early diagnosis of strangulated SBO, several reports have shown that CT scan is useful [\u003cspan additionalcitationids=\"CR8 CR9 CR10 CR11 CR12 CR13 CR14\" citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. However, only a few studies have discussed the differences in the preoperative CT scan findings of necrosis in strangulated SBO. Patients do not always visit a hospital before necrosis develops, and there have been cases in which the diagnosis was not made immediately. However, the patient was monitored and then underwent surgery, which lead to necrosis. Therefore, the prediction of bowel necrosis in strangulated SBO can be challenging.\u003c/p\u003e \u003cp\u003eIdentifying patients at risk for bowel necrosis in strangulated SBO prior to surgery can lead to the case-by-case modification of surgical technique and postoperative management. Moreover, it may lead to improved postoperative outcomes. Therefore, the current study aimed to assess the predictors of preoperative bowel necrosis in strangulated SBO.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003ePatients and data collection\u003c/h2\u003e \u003cp\u003eIn total, 75 consecutive patients underwent surgery for strangulated SBO between January 1, 2012, and March 31, 2024. The diagnosis of SBO can be easily based on physical and CT findings. Thus, patients diagnosed with inguinal, femoral, and obturator hernia and those who only presented with large-bowel strangulation, which was caused by tumors or torsion and colon resection, were excluded from the analysis. The patients were divided into two groups: those with bowel necrosis who underwent bowel resection and those with strangulation release only, not bowel necrosis. Intestinal necrosis was determined based on intraoperative dark-red or black coloration of the strangulated intestine and cessation of peristalsis and blood flow in the strangulated intestine. A gastrointestinal surgeon determined the presence of intestinal necrosis, and intestinal resection was performed. Histopathological analysis of the resected specimens revealed necrotic tissues in all cases. In addition, the without necrosis group did not present with postoperative complications such as perforation and stenosis. This study was performed in accordance with the principles of the Declaration of Helsinki and was approved by the Joint Ethics Review Committee of the Tokushukai Group (TGE01762-011). The need for informed consent was waived due to the retrospective nature of the study.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eCT scan findings\u003c/h3\u003e\n\u003cp\u003eFigure \u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e shows an image of the strangulated SBO. Closed loop was defined as the intestinal tract strangulated by the band. The CT scan value in the strangulated intestinal tract was defined as the average CT scan values of the intestinal contents (closed loop) measured at three random points on simple abdominal CT scan (Figs.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ea, \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eb, \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ec, and \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ed). The CT scan image was magnified, and caution was taken not to include the intestinal wall. A CT scan value\u0026thinsp;\u0026ge;\u0026thinsp;20 should specify Hounsfield Units (HU) consistently. Massive ascites was defined as ascites in two or more sites (the pelvis and around the liver and spleen) on simple CT scan (Figs.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ee, \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ef). Patients with a strangulated intestine with mesenteric fluid were diagnosed with mesenteric fluid (+) (Figs.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eg, \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eh). One investigator (T.S.) performed all CT scan finding analyses under the supervision of an experienced radiologist. The CT scan examinations were performed using one of the hospital\u0026rsquo;s two multidetector CT scanners (Siemens Definition AS 64-channel and Siemens Definition Flash 128-channel). The scanning parameter was 120 kVp, and the dose was automatic. An 2-mm axial-slice thickness was acquired from the hepatic dome to the pubic symphysis. Images were sent to the Picture Archiving and Communication System (YOKOGAWA, FujiFilm Corporation).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eThe demographic characteristics and preoperative CT scan findings of the necrosis and without necrosis groups were compared. Categorical variables were presented as numbers with percentages and compared using the chi-square test. Continuous variables were expressed as medians with ranges and compared using the Mann\u0026ndash;Whitney U test. Univariate and multivariate analyses of the predictive factors of bowel necrosis were performed via a logistic regression analysis. Variables that were significant in the univariate analysis were included in the multivariate analysis. To confirm multicollinearity, the variance inflation factor (VIF) of these factors was calculated. If the VIF was close to 1, there was no multicollinearity issue. If there was a term with a large VIF (use of \u0026ge;\u0026thinsp;5 as a criterion), then the multicollinearity was strong. The cutoff value for intestinal CT scan values was 20 HU. This was because the mean CT scan value in the necrotic group was 19.5. The cutoff values for other continuous variables were also determined using the mean values of the factors. A two-sided P value of \u0026lt;\u0026thinsp;0.05 indicated statistically significant differences. All statistical analyses were performed using JMP version 12 (SAS Institute, Cary, NC, the USA).\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eClinical characteristics of the participants\u003c/h2\u003e \u003cp\u003eOf the 75 patients, 37 (49%) had intestinal necrosis. Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e shows the differences in the clinical characteristics between patients with necrosis and those without. Patients with necrosis had a higher white blood cell (WBC) count (12610/\u0026micro;L vs. 10540/\u0026micro;L, P\u0026thinsp;=\u0026thinsp;0.031) than those without necrosis. There were no differences in the proportion of patients who underwent abdominal surgery between the necrosis and without necrosis groups. Regarding the CT scan findings, patients with necrosis had a higher CT scan value for strangulated SBO (17.2 vs. 8.1 HU, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), a higher massive ascites ratio (84% vs. 42%, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), and a greater mesenteric fluid ratio (65% vs. 13%, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001) than those without necrosis.\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\u003eClinical characteristics between patients with necrosis and those without.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\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=\"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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNecrosis group (n\u0026thinsp;=\u0026thinsp;37)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eNon-necrosis group (n\u0026thinsp;=\u0026thinsp;38)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCharacteristics of the patients\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 \u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSex, male/female\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e15 (41%)/22 (59%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e15 (39%)/23 (61%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.924\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge, years\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e80 [26\u0026thinsp;\u0026minus;\u0026thinsp;92]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e71 [30\u0026thinsp;\u0026minus;\u0026thinsp;96]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.120\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAbdominal surgery\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e21/37 (57%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e28/38 (74%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.123\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWBC count, \u0026micro;L\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12.6 \u0026times; 10\u0026sup3; [3.5 \u0026times; 10\u0026sup3;\u0026minus;31.4 \u0026times; 10\u0026sup3;]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10.5 \u0026times; 10\u0026sup3; [3.5 \u0026times; 10\u0026sup3;\u0026minus;21.6 \u0026times; 10\u0026sup3;]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.031\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCRP level, mg/dL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.99 [0.01\u0026thinsp;\u0026minus;\u0026thinsp;26.9]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.24 [0.02\u0026thinsp;\u0026minus;\u0026thinsp;28.4]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.109\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eCT scan findings\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 \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCT scan value for strangulated SBO, HU\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e17.2 [5.1\u0026thinsp;\u0026minus;\u0026thinsp;62.1]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8.1 [2\u0026thinsp;\u0026minus;\u0026thinsp;27.3]\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMassive ascites\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e32/37 (84%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e16/38 (42%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMesenteric fluid\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e24/37 (65%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5/38 (13%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eCRP, C-reactive protein; CT, computed tomography; SBO, small-bowel obstruction; WBC, white blood cell\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eUnivariate and Multivariate Risk Analysis of the Strangulated SBO with Necrosis\u003c/h2\u003e \u003cp\u003eThe cutoff CT scan values for continuous variables were set at 20 HU in patients with strangulated SBO, and the cutoff WBC count was 13300 \u0026micro;L. As shown in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, the significant risk factors of strangulated SBO with necrosis in the univariate analysis were WBC count\u0026thinsp;\u0026ge;\u0026thinsp;13300 \u0026micro;L (odds ratio [OR]: 2.45, P\u0026thinsp;=\u0026thinsp;0.07), CT scan value\u0026thinsp;\u0026ge;\u0026thinsp;20 HU for strangulated SBO (OR: 17.76, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), massive ascites (OR: 8.8, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), and mesenteric fluid (OR: 12.18, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001). In the multivariate analysis, the risk factors of strangulated SBO with necrosis were a CT value of \u0026ge;\u0026thinsp;20 HU for strangulated SBO (OR: 73.51, 95% confidence interval [95% CI]: 9.35\u0026ndash;1696.11, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), massive ascites (OR: 4.76, 95% CI: 1.00\u0026ndash;27.21, P\u0026thinsp;=\u0026thinsp;0.049), and mesenteric fluid (OR: 21.99, 95% CI: 5.49\u0026ndash;109.41, P\u0026thinsp;\u0026lt;\u0026thinsp;0.001) (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). The VIFs were 1.06 for a CT scan value\u0026thinsp;\u0026ge;\u0026thinsp;20 HU for strangulated SBO, 1.27 for massive ascites, and 1.28 for mesenteric fluid. There were no multicollinearity issues.\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\u003eStrangulated small-bowel obstruction with necrosis based on the univariate predictive analysis\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOR\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e95% CI\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCharacteristics of the patients\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 \u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSex (male)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.41\u0026ndash;2.64\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.92\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.99\u0026ndash;1.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.07\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAbdominal surgery\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.17\u0026ndash;1.22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.12\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWBC count\u0026thinsp;\u0026ge;\u0026thinsp;13,300 \u0026micro;L\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e2.45\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.92\u0026ndash;6.82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.70\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCRP level\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0.96\u0026ndash;1.19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.24\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eCT scan findings\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 \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCT scan value\u0026thinsp;\u0026ge;\u0026thinsp;20 HU for strangulated SBO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e17.76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e3.19\u0026ndash;333.78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMassive ascites\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e8.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e2.99\u0026ndash;30.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMesenteric fluid\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e12.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4.09\u0026ndash;42.73\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eCI, confidence interval; CRP, C-reactive protein; CT, computed tomography; OR, odds ratio; SBO, small-bowel obstruction; WBC, white blood cell\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\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\u003eStrangulated small-bowel obstruction with necrosis based on the multivariate predictive analysis\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariables\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOR\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e95% CI\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eP value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCT scan value\u0026thinsp;\u0026ge;\u0026thinsp;20 HU for strangulated SBO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e73.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e9.35\u0026ndash;1696.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMassive ascites\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e4.76\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1.00\u0026ndash;27.21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.049\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMesenteric fluid\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e21.99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e5.49\u0026ndash;109.41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eCI, confidence interval; CT, computed tomography; OR, odds ratio; SBO, small-bowel obstruction\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eA CT scan value\u0026thinsp;\u0026ge;\u0026thinsp;20 HU for strangulated SBO, massive ascites, and mesenteric fluid were the independent predictive factors of strangulated SBO with necrosis. These findings are strongly suggestive of intestinal necrosis in strangulated bowel obstruction and are indicative of immediate treatment, (i.e., emergency surgery). In addition, the possibility of intestinal resection can be identified before surgery. For example, the use of appropriate surgical technique, blood transfusion preparation, and intensive care unit management can be discussed. Therefore, the bowel may have confirmed laparoscopically and resected. If a massive bowel resection is anticipated, the need for the blood transfusion preparation central venous catheter management may also be determined. Postoperative intensive care unit management is essential in cases requiring bowel resection, and it may be possible to prepare for it. Anticipating bowel resection preoperatively may improve prognosis by preparing for and promptly responding to postoperative management. Therefore, the CT scan values in the intestinal tract of patients with strangulated bowel obstruction should be measured, and massive ascites or mesenteric fluid must be identified. However, the decision to perform surgery must also be based on other clinical factors such as patient stability, comorbidities, and surgical risk assessments results, which may be helpful in the management of strangulated SBO when combined with CT scan findings.\u003c/p\u003e \u003cp\u003eIn addition, gastrointestinal surgeons must be trained to interpret the CT scan findings of strangulated SBO. We are training to identify the small intestine and closed loops of the intestine on CT scan images. At our hospital, we regularly hold study sessions for surgeons and radiologists on CT scan image interpretation to improve their reading skills. Moreover, the preoperative diagnoses and intraoperative findings are compared, and feedback is provided. Hence, the small intestines with strangulated ileus, massive ascites, and mesenteric fluid are easy to identify [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eTo the best of our knowledge, the current study first showed that a CT scan value\u0026thinsp;\u0026ge;\u0026thinsp;20 HU is an independent risk factor of strangulated SBO with necrosis. The CT scan values were \u0026ge;\u0026thinsp;20 HU on a blood basis, which is in close agreement with our previous study results on CT values\u0026thinsp;\u0026ge;\u0026thinsp;24 HU in the appendiceal lumen in gangrenous appendicitis [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. In strangulated SBO with necrosis, an increased intestinal tract pressure attributed to obstruction caused changes such as impaired blood flow in the intestinal tract, insufficient blood supply to the intestinal mucosa, and thrombus formation. This phenomenon results in mucosal necrosis and bleeding in the lumen. Further, in cases of strangulated SBO with necrosis, blood pools may be observed in some cavities of the resected specimens, which can cause high CT scan values in strangulated SBO with necrosis. Whether the observed CT scan values ​​are attributed solely to these mechanisms remains unclear. Therefore, further research should be performed. The CT scan values in strangulated SBO with necrosis are easy to obtain and should be measured aggressively.\u003c/p\u003e \u003cp\u003ePrevious studies have confirmed the discriminatory effect of CT scan findings, particularly massive ascites and the presence of mesenteric fluid, the diagnosis of SBO [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan additionalcitationids=\"CR19 CR20\" citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Our study had a similar result. In terms of mechanism, ascites and mesenteric fluid can be caused by the development of edematous thickening of the intestinal wall and mesentery owing to progressive congestion of the intestinal tract and mesentery with inadequate mesenteric circulation, leading to the leakage of large amounts of effluent and blood. Therefore, if the degree of strangulation is greater, the likelihood of finding large amounts of ascites or mesenteric fluid is higher, Therefore, the patient exhibited findings secondary to strangulation.\u003c/p\u003e \u003cp\u003eCT angiography (CTA) is the gold standard for predicting bowel ischemia, with a sensitivity of 83\u0026ndash;100% and specificity of 61\u0026ndash;93% [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Further, decreased small-bowel wall contrast on CTA indicates intestinal ischemia [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. However, in some patients with asthma, renal impairment, and hyperthyroidism, these tests cannot be performed because contrast agents are contraindicated [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. In addition, CTA cannot be conducted due to the potential risk of iodine-induced nephropathy, high cost, and the unavailability of most primary health care providers [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. The strength of this study is that it presented data that can help resolve all the above mentioned issues, which makes clinical sense. A simple CT scan is essential when diagnosing strangulated bowel obstruction, and there are cases in which contrast agents cannot be used because of the risks involved. However, based on the study results, the use of contrast agents might be reduced if strangulated bowel obstruction with necrosis is suspected based on simple CT scan findings alone. It is also useful from a health care economic point of view. This study did not compare CTA with simple CT. Thus, the findings may be speculative. However, we hope to include them in future studies.\u003c/p\u003e \u003cp\u003eThe current study had several limitations that should be acknowledged. First, this was a retrospective, single-center study with a small sample size. Therefore, patient bias might have existed. To address this, further prospective multicenter studies must be conducted by dedicated associations and rigorous and high-volume tertiary centers to establish reliable evidence-based medicine guidelines. Therefore, it must be recognized that this study was strongly exploratory in nature. Second, there were no clear criteria for determining bowel necrosis. The judgment of intraoperative surgeons was used to determine bowel necrosis. Intestinal necrosis was identified based on the color of the intestine and the cessation of intestinal peristalsis, but it was challenging to establish objective criteria. Nevertheless, there were no complications associated with postoperative bowel necrosis in the without necrosis group. Further, all pathology results of the necrosis group showed necrosis.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eCT scan value ​​\u0026ge;20 HU, high-volume ascites, and mesenteric fluid can be independent predictors of intestinal necrosis in strangulated SBO. However, it must be recognized that these findings are based on single-center retrospective studies with small sample sizes. Therefore, the additional application of CT scan findings may be useful in predicting and managing of necrosis in strangulated SBO.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors want to thank Saki Kasuya (Medical Affairs Division Medical Information\u003c/p\u003e\n\u003cp\u003eManagement Office, Hanyu General Hospital Medical History Department) and\u003c/p\u003e\n\u003cp\u003eMinami Kawakita (Medical Affairs Division Medical Information Management Office,\u003c/p\u003e\n\u003cp\u003eHanyu General Hospital Medical History Department) for their assistance in collecting\u003c/p\u003e\n\u003cp\u003ethe medical data.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eToshiyuki Suzuki: Conceptualization, Methodology, Software, Validation, Formal analysis, Investigation, Resources, Writing–Original draft, Visualization, Project administration, Funding acquisition.\u003c/p\u003e\n\u003cp\u003eAkiyo Matsumoto: Data curation, Supervision.\u003c/p\u003e\n\u003cp\u003eDaisuke Sugiki: Data curation, Supervision.\u003c/p\u003e\n\u003cp\u003eTakahiko Akao: Data curation.\u003c/p\u003e\n\u003cp\u003eHiroshi Matsumoto: Writing–Review \u0026amp; editing.\u003c/p\u003e\n\u003cp\u003eAll authors approved the final version of the manuscript and agree to be held\u003c/p\u003e\n\u003cp\u003eaccountable for all aspects of the work in ensuring that questions related to the accuracy\u003c/p\u003e\n\u003cp\u003eor integrity of any part of the work are appropriately investigated and resolved.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting Interest Statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors have no competing interests to declare that are relevant to the content of this article.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and/or analyzed in the current study are available from the corresponding author upon reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was performed in accordance with the principles of the Declaration of Helsinki and was approved by the Joint Ethics Review Committee of the Tokushukai Group (TGE01762-011). The need for informed consent was waived due to the retrospective nature of this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe need for informed consent was waived due to the retrospective nature of the study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to publish\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors confirm that the participants provided informed consent for the publication of the images in Figure 2.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eMegibow, A. J. Bowel obstruction. Evaluation with CT. \u003cem\u003eRadiol. Clin. North. Am.\u003c/em\u003e \u003cb\u003e32\u003c/b\u003e, 861\u0026ndash;870 (1994).\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBass, K. N., Jones, B. \u0026amp; Bulkley, G. B. Current management of small-bowel obstruction. \u003cem\u003eAdv. 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Prophylactic hydration to protect renal function from intravascular iodinated contrast material in patients at high risk of contrast-induced nephropathy (AMACING): a prospective, randomised, phase 3, controlled, open-label, non-inferiority trial. \u003cem\u003eLancet\u003c/em\u003e \u003cb\u003e389\u003c/b\u003e, 1312\u0026ndash;1322 (2017).\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"CT value, ascites, mesenteric fluid, strangulated small-bowel obstruction, CT findings","lastPublishedDoi":"10.21203/rs.3.rs-6302611/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6302611/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe preoperative diagnosis of intestinal necrosis in strangulated small\u003cb\u003e-\u003c/b\u003ebowel obstruction (SBO) is clinically important because it is prognostically relevant. The current study assessed the predictors of preoperative intestinal necrosis in strangulated SBO. This retrospective single-center study included 75 consecutive patients undergoing surgery for strangulated SBO. Patients with inguinal, femoral, and obturator hernia were excluded from the analysis. The computed tomography (CT) scan value of the strangulated bowel was calculated as the average of the CT scan values ​​of the bowel contents measured at three different random points. The patients were divided into the intestinal necrosis and without necrosis groups. Clinical and CT scan findings were retrospectively analyzed, and univariate and multivariate analyses were performed. The cutoff CT scan value was the mean value. In total, 37 patients presented with intestinal necrosis in the strangulated SBO and 38 did not. In the univariate analysis, a CT scan value\u0026thinsp;\u0026ge;\u0026thinsp;20 HU for strangulated SBO, massive ascites, and mesenteric fluid were significant predictors of preoperative bowel necrosis in strangulated SBO. These factors were also independent predictors of preoperative intestinal necrosis in strangulated SBO in the multivariate analysis. Thus, these factors may help in predicting and managing necrosis in strangulated SBO.\u003c/p\u003e","manuscriptTitle":"Computed Tomography Scan Predictors of Intestinal Necrosis in Strangulated Small-Bowel Obstruction: A Retrospective Cohort Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-04-03 10:29:09","doi":"10.21203/rs.3.rs-6302611/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-04-09T06:07:45+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-04-08T07:05:18+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"182011507525883548173104230954754823074","date":"2025-03-28T07:31:20+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-03-28T07:15:41+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"108088064992007301674850671341693404047","date":"2025-03-28T07:08:50+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-03-28T06:53:57+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-03-28T06:48:47+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-03-28T06:41:43+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-03-26T07:08:38+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2025-03-25T10:01:21+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"ab18fdac-246f-4d94-9279-3df22f7a31e9","owner":[],"postedDate":"April 3rd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[{"id":46452063,"name":"Health sciences/Diseases"},{"id":46452064,"name":"Health sciences/Medical research"}],"tags":[],"updatedAt":"2025-07-28T16:06:47+00:00","versionOfRecord":{"articleIdentity":"rs-6302611","link":"https://doi.org/10.1038/s41598-025-13186-x","journal":{"identity":"scientific-reports","isVorOnly":false,"title":"Scientific Reports"},"publishedOn":"2025-07-24 15:58:08","publishedOnDateReadable":"July 24th, 2025"},"versionCreatedAt":"2025-04-03 10:29:09","video":"","vorDoi":"10.1038/s41598-025-13186-x","vorDoiUrl":"https://doi.org/10.1038/s41598-025-13186-x","workflowStages":[]},"version":"v1","identity":"rs-6302611","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6302611","identity":"rs-6302611","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}