From Intraoperative Visual Inspection to Postoperative Quantification: ICG Fluorescence Angiography for Acute Mesenteric Ischemia Validated by Histopathology

From Intraoperative Visual Inspection to Postoperative Quantification: ICG Fluorescence Angiography for Acute Mesenteric Ischemia Validated by Histopathology | 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 Case Report From Intraoperative Visual Inspection to Postoperative Quantification: ICG Fluorescence Angiography for Acute Mesenteric Ischemia Validated by Histopathology Zhi Fan, Shuang Guo, Peng Zhang, Tianyi Ma, Ying Xiao, Rongrong Zhu, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8460839/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 14 You are reading this latest preprint version Abstract Introduction: Acute mesenteric ischemia (AMI) is a rare and life-threatening condition that leads to intestinal necrosis. Accurate assessment of intestinal viability and perfusion is crucial for reducing its high mortality rate. Case Presentation: A 65-year-old female patient diagnosed with acute mesenteric ischemia complicated by intestinal necrosis underwent exploratory laparotomy. Under indocyanine green (ICG) imaging guidance, the necrotic bowel segments were resected. Postoperative quantitative analysis and histopathology confirmed intestinal necrosis. Discussion: Due to the lack of specific appearance in the early stages of intestinal wall necrosis caused by acute mesenteric ischemia, relying solely on white light or subjective qualitative ICG fluorescence imaging makes it difficult to precisely define the resection margin. This case innovatively applied quantitative ICG fluorescence analysis, revealing a correspondence between specific perfusion parameters, including T 0 and slope, and the histopathological grading of intestinal necrosis. This demonstrates that quantitative ICG may provide surgeons with an objective intraoperative decision-making tool. Conclusion: This case demonstrates that ICG fluorescence imaging combined with quantitative analysis has the potential to serve as an effective method for objectively assessing intestinal viability. Acute mesenteric ischemia Indocyanine green Fluorescent angiography Quantitative analysis Intestinal perfusion Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Acute mesenteric ischemia is a condition characterized by reduced or interrupted blood flow to the intestines, leading to ischemic necrosis of the intestinal mucosa and potentially full-thickness necrosis of the intestinal wall( 1 ). From an epidemiological perspective, the incidence of AMI is relatively low, but it increases significantly with age. Among individuals over 75 years old presenting with abdominal pain, AMI has become one of the primary causes, surpassing appendicitis( 2 ). Etiologically, AMI is primarily categorized into arterial, non-occlusive, and venous types, with the arterial form being the most prevalent( 3 ). The prognosis is extremely poor, with a medium-to-long-term mortality rate approaching 70%( 3 ). Without timely intervention, prolonged ischemia leads to full-thickness necrosis of the bowel, resulting in suppurative infection and potentially fatal shock( 4 ). The current mainstream treatment strategy holds that early revascularization should be performed for most AMI patients. If preoperative assessment suggests intestinal necrosis, exploratory laparotomy is required to resect the necrotic bowel segments. However, during exploration, it is sometimes difficult to clearly distinguish between necrotic and non-necrotic tissue( 5 ). ICG imaging is currently a widely used method in clinical practice, but it primarily relies on subjective qualitative analysis( 6 ). Notably, qualitative ICG alone does not significantly improve outcomes. A clinical trial primarily involving AMI cases demonstrated that qualitative ICG did not alter rates of progressive intestinal necrosis, reoperation, or mortality among patients undergoing surgery( 7 ). Consequently, quantitative ICG assessment has become an urgent clinical priority requiring breakthroughs. Its application may assist surgeons in accurately determining whether intestinal necrosis has occurred during surgery and in defining the resection margin. However, existing research lacks detailed reports on quantitative ICG during surgery for AMI patients. In this case, we first employed ICG technology during surgery to qualitatively analyze intestinal necrosis. Postoperatively, we retrospectively conducted a quantitative analysis of ICG perfusion patterns. The results supported the initial assessment and were ultimately compared with pathological findings of necrotic bowel segments, revealing a relationship between quantitative ICG parameters and the extent of necrosis. This paper reports a case of acute myocardial infarction caused by SMA embolism in a 65-year-old female patient. The case report adheres to the SCARE 2020 Guidelines for Surgical Case Reports( 8 ). Case Presentation A 65-year-old female patient was admitted for “mid-upper abdominal pain for 4 days, worsening for 1 day.” The patient initially presented with mid-upper abdominal pain, which subsequently intensified and spread diffusely throughout the abdomen. Abdominal computed tomography angiography (CTA) revealed thromboembolism at the distal origin of the superior mesenteric artery (SMA) (Fig. 1 ), confirming a diagnosis of AMI. On admission physical examination, tenderness and rebound tenderness were noted in the right upper quadrant and bilateral lower abdomen, without muscle guarding. Laboratory tests showed marked inflammation: C-reactive protein (CRP) was elevated at 152.73 mg/L, white blood cell count was 24.24 × 10⁹/L, D-dimer 0.89 mg/L FEU. Emergency blood gas analysis showed pH 7.44 with mildly elevated lactate at 1.4 mmol/L. Comprehensive assessment of symptoms, signs, and imaging findings indicated risk of intestinal necrosis. Emergency interventional thrombectomy and exploratory laparotomy were performed. Immediately following endovascular thrombectomy, laparoscopic exploration was performed. Under white light illumination, a segment of small intestine approximately 5 cm in length appeared grayish-white, raising suspicion of necrosis (Fig. 2 ). The demarcation between this affected area and the adjacent intestinal tracts on both sides was relatively distinct. To assess intestinal blood supply and define resection margins, intraoperative intravenous injection of ICG was administered. Crucially, the fluorescence imaging lens was fixed to focus on the suspected necrotic area and its margins, capturing the entire perfusion process from ICG injection to tissue visualization. Based on macroscopic findings combined with qualitative fluorescence imaging results (quantitative data supported resection margins), the necrotic intestinal segment was resected and anastomosed. Postoperatively, we imported the intraoperative ICG imaging video into analysis software for retrospective fluorescence-time intensity quantitative analysis (Fig. 2 ). Three regions of interest (ROIs) were selected on the images: the necrotic core, the necrotic margin, and the normally perfused area. We evaluated the perfusion kinetics using the following parameters derived from the fluorescence-time curve (FTC). The time to first fluorescence signal (T 0 ) was defined as the delay from ICG administration to the first significant increase in fluorescence intensity. Following T 0 , the intensity increased until reaching the maximum fluorescence intensity (Fmax); this duration is termed time-to-peak (TTP). Finally, the mean ascending slope (Slope) was calculated as the differential of the FTC during the TTP interval (Fig. 3 ). We performed point-to-point comparisons of these parameters with pathological findings from resected specimens. Referencing the standard histological grading for intestinal necrosis( 9 ), pathological results showed Grade 8 necrosis in the central necrosis zone (Fig. 4 a), Grade 7 necrosis in the marginal necrosis zone (Fig. 4 b), and Grade 2–3 perfusion in the normal perfusion zone (Fig. 4 c). Data analysis revealed a clear correlation between higher pathological necrosis grades and larger T 0 values or smaller Slope values. In contrast, Fmax and TTP showed no significant correlation in this case(Table 1 ). Table 1 Comparison of Quantitative ICG Fluorescence Parameters Across Different Intestinal Regions and Pathological Grading. Normal blood supply area Right border area Necrotic central area T0 5.55 6.83 7.38 Slope 62.4 46.2 5.4 F max 582 594 18 TTP 3.62 2.92 2.39 Pathological Grading Grade2-3 Grade7 Grade8 The patient recovered well after surgery and was transferred back to the general ward after two days of observation in the intensive care unit (ICU). The patient was subsequently discharged without complications. The patient has been discharged for four months and is currently tolerating a normal diet. Discussion Patients with acute myocardial infarction who are suspected of having intestinal necrosis should undergo exploratory laparotomy as soon as possible to resect necrotic bowel segments( 4 ). During operation, the most challenging aspect lies in distinguishing viable from necrotic bowel segments to ensure optimal surgical outcomes( 10 ). The degree of ischemia, its etiology, and duration vary among patients. Moreover, necrotic segments may not initially exhibit characteristic signs of necrosis( 11 ). Therefore, objective tools are essential during surgical exploration to assess intestinal perfusion and viability( 5 ). Regarding the application and current research status of quantitative ICG in gastrointestinal diseases, limited exploratory studies have been conducted. in the field of colorectal surgery, quantitative ICG has been extensively studied for predicting anastomotic leaks. A study involving 70 patients who underwent anastomosis demonstrated that when the fluorescence intensity at the anastomotic site was below 169 U or the slope was less than 14.4 U/s, the incidence of postoperative anastomotic leaks significantly increased( 12 ). Furthermore, one study demonstrated differences in fluorescence dynamic patterns between ischemic intestinal segments and normoperfused control segments in four patients with compromised mesenteric blood supply through postoperative quantitative analysis of fluorescence dynamics( 13 ). However, quantitative intraoperative assessment criteria for AMI remain largely unexplored in this critical care setting. In this case, a standardized ICG quantification fluorescence imaging protocol was applied. During the procedure, ICG was administered at a dose of 0.25 mg/kg based on the patient's weight. A stable camera position was maintained over the suspected necrotic area. Following ICG injection, the endoscopic camera's recording function was activated and maintained for a continuous 1-minute recording. Postoperatively, we correlated intestinal pathological tissue findings with ICG quantitative parameters, revealing significant correlations: higher Slope values indicated better blood perfusion and lower tissue necrosis severity; while a longer T 0 indicated delayed blood flow arrival and more severe tissue necrosis. Although fluorescence intensity also showed a decreasing trend with increasing necrosis severity, its correlation was less pronounced than that of Slope and T 0 in this case. These findings constitute the primary discoveries of this study. This study first proposes the potential of using quantitative ICG in AMI surgery to aid in the diagnosis of intestinal necrosis. Moving forward, we need to conduct postoperative ICG imaging analysis on a larger number of cases to progressively establish a standardized mathematical model correlating ICG quantitative parameters with the extent of intestinal necrosis. This will provide surgeons with new objective indicators to guide precise resection during future surgeries, ensuring the removal of necrotic tissue while maximizing the preservation of functional bowel segments. Conclusion This case study confirms that quantitative ICG fluorescence analysis parameters—particularly T0 and Slope—exhibit a correspondence with the extent of histopathological necrosis in intestinal wall tissue during acute mesenteric ischemia surgery. As an objective assessment tool, quantitative ICG shows potential to surpass traditional macroscopic and qualitative judgments, offering promise for more precise decisions regarding intestinal resection. Abbreviations AMI acute mesenteric ischemia ICG indocyanine green CTA tomography angiography SMA superior mesenteric artery CRP c-reactive protein ROIs regions of interest FTC fluorescence-time curve TTP termed time-to-peak ICU intensive care unit Declarations Acknowledgements Not applicable. Authors’contributions Z.F., S.G., P.Z., T.Y.M., W.W.W.: study concept and data collection; Z.F., S.G.: writing the manuscript; R.R.Z., W.W.W.: review & editing the manuscript; Y.X.: histopathology analysis. All authors read and approved the final manuscript. Funding This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors Data availability All data generated or analyzed during this case report are included in this published article and its supplementary information files. Ethics approval and consent to participate Not applicable. Consent for publication Written informed consent was obtained from the patient for publication and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal on request Competing interests The authors declare no competing interests. References Patel A, Kaleya RN, Sammartano RJ. Pathophysiology of mesenteric ischemia. Surg Clin North Am. 1992;72(1):31–41. Kärkkäinen JM, Lehtimäki TT, Manninen H, Paajanen H. Acute Mesenteric Ischemia Is a More Common Cause than Expected of Acute Abdomen in the Elderly. J Gastrointest surgery: official J Soc Surg Aliment Tract. 2015;19(8):1407–14. Tamme K, Reintam Blaser A, Laisaar KT, Mändul M, Kals J, Forbes A, et al. Incidence and outcomes of acute mesenteric ischaemia: a systematic review and meta-analysis. BMJ open. 2022;12(10):e062846. Koelemay MJ, Geelkerken RH, Kärkkäinen J, Leone N, Antoniou GA, de Bruin JL, et al. editors. 's Choice - European Society for Vascular Surgery (ESVS) 2025 Clinical Practice Guidelines on the Management of Diseases of the Mesenteric and Renal Arteries and Veins. European journal of vascular and endovascular surgery: the official journal of the European Society for Vascular Surgery. 2025;70(2):153–218. Mehdorn M, Ebel S, Köhler H, Gockel I, Jansen-Winkeln B. Hyperspectral imaging and indocyanine green fluorescence angiography in acute mesenteric ischemia: A case report on how to visualize intestinal perfusion. Int J Surg case Rep. 2021;82:105853. Bryski MG, Frenzel Sulyok LG, Kaplan L, Singhal S, Keating JJ. Techniques for intraoperative evaluation of bowel viability in mesenteric ischemia: A review. Am J Surg. 2020;220(2):309–15. Joosten JJ, Longchamp G, Khan MF, Lameris W, van Berge Henegouwen MI, Bemelman WA, et al. The use of fluorescence angiography to assess bowel viability in the acute setting: an international, multi-centre case series. Surg Endosc. 2022;36(10):7369–75. Agha RA, Franchi T, Sohrabi C, Mathew G, Kerwan A. The SCARE 2020 Guideline: Updating Consensus Surgical CAse REport (SCARE) Guidelines. International journal of surgery (London, England). 2020;84:226 – 30. Park PO, Haglund U, Bulkley GB, Fält K. The sequence of development of intestinal tissue injury after strangulation ischemia and reperfusion. Surgery. 1990;107(5):574–80. Аlexander K, Ismail M, Alexander M, Ivan T, Olga V, Dmitry S, et al. Use of ICG imaging to confirm bowel viability after upper mesenteric stenting in patient with acute mesenteric ischemia: Case report. Int J Surg case Rep. 2019;61:322–6. Szoka N, Kahn M. Acute-On-Chronic Mesenteric Ischemia: The Use of Fluorescence Guidance to Diagnose a Nonsurvivable Injury. Case Rep Surg. 2022;2022:5459774. Gomez-Rosado JC, Valdes-Hernandez J, Cintas-Catena J, Cano-Matias A, Perez-Sanchez A, Del Rio-Lafuente FJ, et al. Feasibility of quantitative analysis of colonic perfusion using indocyanine green to prevent anastomotic leak in colorectal surgery. Surg Endosc. 2022;36(2):1688–95. Meijer RPJ, van Manen L, Hartgrink HH, Burggraaf J, Gioux S, Vahrmeijer AL et al. Quantitative dynamic near-infrared fluorescence imaging using indocyanine green for analysis of bowel perfusion after mesenteric resection. J Biomed Opt. 2021;26(6). 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-8460839","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":583759477,"identity":"9112d2ba-79dc-48ed-99a3-65a16b09a3b5","order_by":0,"name":"Zhi Fan","email":"","orcid":"","institution":"Department of Vascular Surgery, Beijing Tsinghua Changgung Hospital, School of Medicine, Tsinghua University","correspondingAuthor":false,"prefix":"","firstName":"Zhi","middleName":"","lastName":"Fan","suffix":""},{"id":583759481,"identity":"5015b9ec-1197-400c-bf16-749375ef09ad","order_by":1,"name":"Shuang Guo","email":"","orcid":"","institution":"Department of Vascular Surgery, Beijing Tsinghua Changgung Hospital, School of Medicine, Tsinghua University","correspondingAuthor":false,"prefix":"","firstName":"Shuang","middleName":"","lastName":"Guo","suffix":""},{"id":583759487,"identity":"acdaa17d-7d50-4d91-a208-d907778c1551","order_by":2,"name":"Peng Zhang","email":"","orcid":"","institution":"Department of Gastroenterology Surgery, Beijing Tsinghua Changgung Hospital, School of Medicine, Tsinghua University","correspondingAuthor":false,"prefix":"","firstName":"Peng","middleName":"","lastName":"Zhang","suffix":""},{"id":583759490,"identity":"5f0c5cd9-71af-4eda-a159-e9f0ba46c37c","order_by":3,"name":"Tianyi Ma","email":"","orcid":"","institution":"Department of Gastroenterology Surgery, Beijing Tsinghua Changgung Hospital, School of Medicine, Tsinghua University","correspondingAuthor":false,"prefix":"","firstName":"Tianyi","middleName":"","lastName":"Ma","suffix":""},{"id":583759492,"identity":"fcaff545-1190-470a-b7c9-0bdb9f2d80b2","order_by":4,"name":"Ying Xiao","email":"","orcid":"","institution":"Department of Pathology, Beijing Tsinghua Changgung Hospital, School of Medicine, Tsinghua University","correspondingAuthor":false,"prefix":"","firstName":"Ying","middleName":"","lastName":"Xiao","suffix":""},{"id":583759495,"identity":"639d85c0-f298-44f1-a5f7-a346a6e5ae7b","order_by":5,"name":"Rongrong Zhu","email":"","orcid":"","institution":"Department of Vascular Surgery, Beijing Tsinghua Changgung Hospital, School of Medicine, Tsinghua University","correspondingAuthor":false,"prefix":"","firstName":"Rongrong","middleName":"","lastName":"Zhu","suffix":""},{"id":583759497,"identity":"9a84bc55-7931-4c12-9b22-63f0c4ee1e27","order_by":6,"name":"Weiwei Wu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA30lEQVRIiWNgGAWjYLCCBAMbHn72HgYGxgYg7wAxWj5UpMlJ9pxhbCBaC+OMM4eNDWbkEKnF4EaO4WfetsOJGyTfHn/wcweDHN+NBMbPBfi1GEvztqUnbpfOS2zsPcNgLHkjgVl6Bh4tZrdzNwC1WCfunJ1j2MzYxpC44UYCGzMPfi2bf/O2MSduuHkGrKWeGC3bJGeccTY2uMED1pJgQEiL/f333ywggZyXOLO3TcJw5pmHzdL4tEj2HEu+AYnKswc+/Gyzkec7nnzwMz4t6ECCAZoGRsEoGAWjYBRQAgBVolRySPh4KAAAAABJRU5ErkJggg==","orcid":"","institution":"Department of Vascular Surgery, Beijing Tsinghua Changgung Hospital, School of Medicine, Tsinghua University","correspondingAuthor":true,"prefix":"","firstName":"Weiwei","middleName":"","lastName":"Wu","suffix":""}],"badges":[],"createdAt":"2025-12-27 11:53:11","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8460839/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8460839/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":101880957,"identity":"042c8708-3db9-4db5-88e3-19c9e15d57d5","added_by":"auto","created_at":"2026-02-04 15:08:20","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":56211,"visible":true,"origin":"","legend":"\u003cp\u003ePreoperative abdominal computed tomography angiography (CTA). Coronary images reveal a filling defect (indicated by arrows) distal to the origin of the superior mesenteric artery (SMA), suggesting thromboembolism.\u003c/p\u003e","description":"","filename":"1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8460839/v1/a91965fb27f55ec1b51e8dd7.jpg"},{"id":101789482,"identity":"05f634ae-c041-46b3-87ae-44c507d1dc94","added_by":"auto","created_at":"2026-02-03 15:57:45","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":102449,"visible":true,"origin":"","legend":"\u003cp\u003eIntraoperative white light findings and indocyanine green (ICG) fluorescence angiograph.\u003c/p\u003e","description":"","filename":"2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8460839/v1/af942032bbbd857984789d9e.jpg"},{"id":101881362,"identity":"3eab91d9-6824-488a-a4f9-179cca8dd74a","added_by":"auto","created_at":"2026-02-04 15:11:44","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":42895,"visible":true,"origin":"","legend":"\u003cp\u003eFluorescence-time intensity quantitative analysis result.\u003c/p\u003e","description":"","filename":"3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8460839/v1/9212e2a3c56d9029572f0f9e.jpg"},{"id":101880947,"identity":"1412ce61-41d8-4954-bb6c-c7554e59f5dc","added_by":"auto","created_at":"2026-02-04 15:08:15","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":75668,"visible":true,"origin":"","legend":"\u003cp\u003eHistopathological examination of resected intestinal segment (H\u0026amp;E staining, ×100)、\u003c/p\u003e","description":"","filename":"4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-8460839/v1/477457b26c577f8a9f180b15.jpg"},{"id":101882524,"identity":"5d233322-1f5b-4d02-82db-b778d75f79c4","added_by":"auto","created_at":"2026-02-04 15:23:28","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":647117,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8460839/v1/445d4fd6-2be7-43c8-b1ef-825adcceae51.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"From Intraoperative Visual Inspection to Postoperative Quantification: ICG Fluorescence Angiography for Acute Mesenteric Ischemia Validated by Histopathology","fulltext":[{"header":"Introduction","content":"\u003cp\u003eAcute mesenteric ischemia is a condition characterized by reduced or interrupted blood flow to the intestines, leading to ischemic necrosis of the intestinal mucosa and potentially full-thickness necrosis of the intestinal wall(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). From an epidemiological perspective, the incidence of AMI is relatively low, but it increases significantly with age. Among individuals over 75 years old presenting with abdominal pain, AMI has become one of the primary causes, surpassing appendicitis(\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). Etiologically, AMI is primarily categorized into arterial, non-occlusive, and venous types, with the arterial form being the most prevalent(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). The prognosis is extremely poor, with a medium-to-long-term mortality rate approaching 70%(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). Without timely intervention, prolonged ischemia leads to full-thickness necrosis of the bowel, resulting in suppurative infection and potentially fatal shock(\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe current mainstream treatment strategy holds that early revascularization should be performed for most AMI patients. If preoperative assessment suggests intestinal necrosis, exploratory laparotomy is required to resect the necrotic bowel segments. However, during exploration, it is sometimes difficult to clearly distinguish between necrotic and non-necrotic tissue(\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eICG imaging is currently a widely used method in clinical practice, but it primarily relies on subjective qualitative analysis(\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). Notably, qualitative ICG alone does not significantly improve outcomes. A clinical trial primarily involving AMI cases demonstrated that qualitative ICG did not alter rates of progressive intestinal necrosis, reoperation, or mortality among patients undergoing surgery(\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e). Consequently, quantitative ICG assessment has become an urgent clinical priority requiring breakthroughs. Its application may assist surgeons in accurately determining whether intestinal necrosis has occurred during surgery and in defining the resection margin. However, existing research lacks detailed reports on quantitative ICG during surgery for AMI patients.\u003c/p\u003e \u003cp\u003eIn this case, we first employed ICG technology during surgery to qualitatively analyze intestinal necrosis. Postoperatively, we retrospectively conducted a quantitative analysis of ICG perfusion patterns. The results supported the initial assessment and were ultimately compared with pathological findings of necrotic bowel segments, revealing a relationship between quantitative ICG parameters and the extent of necrosis. This paper reports a case of acute myocardial infarction caused by SMA embolism in a 65-year-old female patient. The case report adheres to the SCARE 2020 Guidelines for Surgical Case Reports(\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e).\u003c/p\u003e"},{"header":"Case Presentation","content":"\u003cp\u003eA 65-year-old female patient was admitted for \u0026ldquo;mid-upper abdominal pain for 4 days, worsening for 1 day.\u0026rdquo; The patient initially presented with mid-upper abdominal pain, which subsequently intensified and spread diffusely throughout the abdomen. Abdominal computed tomography angiography (CTA) revealed thromboembolism at the distal origin of the superior mesenteric artery (SMA) (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e), confirming a diagnosis of AMI. On admission physical examination, tenderness and rebound tenderness were noted in the right upper quadrant and bilateral lower abdomen, without muscle guarding. Laboratory tests showed marked inflammation: C-reactive protein (CRP) was elevated at 152.73 mg/L, white blood cell count was 24.24 \u0026times; 10⁹/L, D-dimer 0.89 mg/L FEU. Emergency blood gas analysis showed pH 7.44 with mildly elevated lactate at 1.4 mmol/L. Comprehensive assessment of symptoms, signs, and imaging findings indicated risk of intestinal necrosis. Emergency interventional thrombectomy and exploratory laparotomy were performed.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eImmediately following endovascular thrombectomy, laparoscopic exploration was performed. Under white light illumination, a segment of small intestine approximately 5 cm in length appeared grayish-white, raising suspicion of necrosis (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The demarcation between this affected area and the adjacent intestinal tracts on both sides was relatively distinct. To assess intestinal blood supply and define resection margins, intraoperative intravenous injection of ICG was administered. Crucially, the fluorescence imaging lens was fixed to focus on the suspected necrotic area and its margins, capturing the entire perfusion process from ICG injection to tissue visualization. Based on macroscopic findings combined with qualitative fluorescence imaging results (quantitative data supported resection margins), the necrotic intestinal segment was resected and anastomosed.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003ePostoperatively, we imported the intraoperative ICG imaging video into analysis software for retrospective fluorescence-time intensity quantitative analysis (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Three regions of interest (ROIs) were selected on the images: the necrotic core, the necrotic margin, and the normally perfused area. We evaluated the perfusion kinetics using the following parameters derived from the fluorescence-time curve (FTC). The time to first fluorescence signal (T\u003csub\u003e0\u003c/sub\u003e) was defined as the delay from ICG administration to the first significant increase in fluorescence intensity. Following T\u003csub\u003e0\u003c/sub\u003e, the intensity increased until reaching the maximum fluorescence intensity (Fmax); this duration is termed time-to-peak (TTP). Finally, the mean ascending slope (Slope) was calculated as the differential of the FTC during the TTP interval (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). We performed point-to-point comparisons of these parameters with pathological findings from resected specimens. Referencing the standard histological grading for intestinal necrosis(\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e), pathological results showed Grade 8 necrosis in the central necrosis zone (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ea), Grade 7 necrosis in the marginal necrosis zone (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eb), and Grade 2\u0026ndash;3 perfusion in the normal perfusion zone (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ec). Data analysis revealed a clear correlation between higher pathological necrosis grades and larger T\u003csub\u003e0\u003c/sub\u003e values or smaller Slope values. In contrast, Fmax and TTP showed no significant correlation in this case(Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \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\u003eComparison of Quantitative ICG Fluorescence Parameters Across Different Intestinal Regions and Pathological Grading.\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=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNormal blood supply area\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eRight border area\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eNecrotic central area\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.55\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6.83\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7.38\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSlope\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e62.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e46.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eF\u003csub\u003emax\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e582\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e594\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e18\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTTP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3.62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.92\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.39\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePathological Grading\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eGrade2-3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eGrade7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eGrade8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe patient recovered well after surgery and was transferred back to the general ward after two days of observation in the intensive care unit (ICU). The patient was subsequently discharged without complications. The patient has been discharged for four months and is currently tolerating a normal diet.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003ePatients with acute myocardial infarction who are suspected of having intestinal necrosis should undergo exploratory laparotomy as soon as possible to resect necrotic bowel segments(\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e). During operation, the most challenging aspect lies in distinguishing viable from necrotic bowel segments to ensure optimal surgical outcomes(\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e). The degree of ischemia, its etiology, and duration vary among patients. Moreover, necrotic segments may not initially exhibit characteristic signs of necrosis(\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e). Therefore, objective tools are essential during surgical exploration to assess intestinal perfusion and viability(\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eRegarding the application and current research status of quantitative ICG in gastrointestinal diseases, limited exploratory studies have been conducted. in the field of colorectal surgery, quantitative ICG has been extensively studied for predicting anastomotic leaks. A study involving 70 patients who underwent anastomosis demonstrated that when the fluorescence intensity at the anastomotic site was below 169 U or the slope was less than 14.4 U/s, the incidence of postoperative anastomotic leaks significantly increased(\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e). Furthermore, one study demonstrated differences in fluorescence dynamic patterns between ischemic intestinal segments and normoperfused control segments in four patients with compromised mesenteric blood supply through postoperative quantitative analysis of fluorescence dynamics(\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e). However, quantitative intraoperative assessment criteria for AMI remain largely unexplored in this critical care setting.\u003c/p\u003e \u003cp\u003eIn this case, a standardized ICG quantification fluorescence imaging protocol was applied. During the procedure, ICG was administered at a dose of 0.25 mg/kg based on the patient's weight. A stable camera position was maintained over the suspected necrotic area. Following ICG injection, the endoscopic camera's recording function was activated and maintained for a continuous 1-minute recording. Postoperatively, we correlated intestinal pathological tissue findings with ICG quantitative parameters, revealing significant correlations: higher Slope values indicated better blood perfusion and lower tissue necrosis severity; while a longer T\u003csub\u003e0\u003c/sub\u003e indicated delayed blood flow arrival and more severe tissue necrosis. Although fluorescence intensity also showed a decreasing trend with increasing necrosis severity, its correlation was less pronounced than that of Slope and T\u003csub\u003e0\u003c/sub\u003e in this case. These findings constitute the primary discoveries of this study.\u003c/p\u003e \u003cp\u003eThis study first proposes the potential of using quantitative ICG in AMI surgery to aid in the diagnosis of intestinal necrosis. Moving forward, we need to conduct postoperative ICG imaging analysis on a larger number of cases to progressively establish a standardized mathematical model correlating ICG quantitative parameters with the extent of intestinal necrosis. This will provide surgeons with new objective indicators to guide precise resection during future surgeries, ensuring the removal of necrotic tissue while maximizing the preservation of functional bowel segments.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis case study confirms that quantitative ICG fluorescence analysis parameters\u0026mdash;particularly T0 and Slope\u0026mdash;exhibit a correspondence with the extent of histopathological necrosis in intestinal wall tissue during acute mesenteric ischemia surgery. As an objective assessment tool, quantitative ICG shows potential to surpass traditional macroscopic and qualitative judgments, offering promise for more precise decisions regarding intestinal resection.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eAMI acute mesenteric ischemia\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eICG indocyanine green\u003c/p\u003e\n\u003cp\u003eCTA tomography angiography\u003c/p\u003e\n\u003cp\u003eSMA superior mesenteric artery\u003c/p\u003e\n\u003cp\u003eCRP c-reactive protein\u003c/p\u003e\n\u003cp\u003eROIs regions of interest\u003c/p\u003e\n\u003cp\u003eFTC fluorescence-time curve\u003c/p\u003e\n\u003cp\u003eTTP termed time-to-peak\u003c/p\u003e\n\u003cp\u003eICU intensive care unit\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eAcknowledgements\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003eAuthors\u0026rsquo;contributions\u003c/p\u003e\n\u003cp\u003eZ.F., S.G., P.Z., T.Y.M., W.W.W.: study concept and data collection; Z.F., S.G.: writing the manuscript; R.R.Z., W.W.W.: review \u0026amp; editing the manuscript; Y.X.: histopathology analysis. All authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003eFunding\u0026nbsp;\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\u003eData availability\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAll data generated or analyzed during this case report are included in this published article and its supplementary information files.\u003c/p\u003e\n\u003cp\u003eEthics approval and consent to participate\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003eConsent for publication\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eWritten informed consent was obtained from the patient for publication and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal on request\u003c/p\u003e\n\u003cp\u003eCompeting interests\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003ePatel A, Kaleya RN, Sammartano RJ. Pathophysiology of mesenteric ischemia. Surg Clin North Am. 1992;72(1):31\u0026ndash;41.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eK\u0026auml;rkk\u0026auml;inen JM, Lehtim\u0026auml;ki TT, Manninen H, Paajanen H. Acute Mesenteric Ischemia Is a More Common Cause than Expected of Acute Abdomen in the Elderly. J Gastrointest surgery: official J Soc Surg Aliment Tract. 2015;19(8):1407\u0026ndash;14.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTamme K, Reintam Blaser A, Laisaar KT, M\u0026auml;ndul M, Kals J, Forbes A, et al. Incidence and outcomes of acute mesenteric ischaemia: a systematic review and meta-analysis. BMJ open. 2022;12(10):e062846.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKoelemay MJ, Geelkerken RH, K\u0026auml;rkk\u0026auml;inen J, Leone N, Antoniou GA, de Bruin JL, et al. editors. 's Choice - European Society for Vascular Surgery (ESVS) 2025 Clinical Practice Guidelines on the Management of Diseases of the Mesenteric and Renal Arteries and Veins. European journal of vascular and endovascular surgery: the official journal of the European Society for Vascular Surgery. 2025;70(2):153\u0026ndash;218.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMehdorn M, Ebel S, K\u0026ouml;hler H, Gockel I, Jansen-Winkeln B. Hyperspectral imaging and indocyanine green fluorescence angiography in acute mesenteric ischemia: A case report on how to visualize intestinal perfusion. Int J Surg case Rep. 2021;82:105853.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBryski MG, Frenzel Sulyok LG, Kaplan L, Singhal S, Keating JJ. Techniques for intraoperative evaluation of bowel viability in mesenteric ischemia: A review. Am J Surg. 2020;220(2):309\u0026ndash;15.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJoosten JJ, Longchamp G, Khan MF, Lameris W, van Berge Henegouwen MI, Bemelman WA, et al. The use of fluorescence angiography to assess bowel viability in the acute setting: an international, multi-centre case series. Surg Endosc. 2022;36(10):7369\u0026ndash;75.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAgha RA, Franchi T, Sohrabi C, Mathew G, Kerwan A. The SCARE 2020 Guideline: Updating Consensus Surgical CAse REport (SCARE) Guidelines. International journal of surgery (London, England). 2020;84:226\u0026thinsp;\u0026ndash;\u0026thinsp;30.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePark PO, Haglund U, Bulkley GB, F\u0026auml;lt K. The sequence of development of intestinal tissue injury after strangulation ischemia and reperfusion. Surgery. 1990;107(5):574\u0026ndash;80.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eАlexander K, Ismail M, Alexander M, Ivan T, Olga V, Dmitry S, et al. Use of ICG imaging to confirm bowel viability after upper mesenteric stenting in patient with acute mesenteric ischemia: Case report. Int J Surg case Rep. 2019;61:322\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSzoka N, Kahn M. Acute-On-Chronic Mesenteric Ischemia: The Use of Fluorescence Guidance to Diagnose a Nonsurvivable Injury. Case Rep Surg. 2022;2022:5459774.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGomez-Rosado JC, Valdes-Hernandez J, Cintas-Catena J, Cano-Matias A, Perez-Sanchez A, Del Rio-Lafuente FJ, et al. Feasibility of quantitative analysis of colonic perfusion using indocyanine green to prevent anastomotic leak in colorectal surgery. Surg Endosc. 2022;36(2):1688\u0026ndash;95.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMeijer RPJ, van Manen L, Hartgrink HH, Burggraaf J, Gioux S, Vahrmeijer AL et al. Quantitative dynamic near-infrared fluorescence imaging using indocyanine green for analysis of bowel perfusion after mesenteric resection. J Biomed Opt. 2021;26(6).\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":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bsur","sideBox":"Learn more about [BMC Surgery](http://bmcsurg.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bsur/default.aspx","title":"BMC Surgery","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Acute mesenteric ischemia, Indocyanine green, Fluorescent angiography, Quantitative analysis, Intestinal perfusion","lastPublishedDoi":"10.21203/rs.3.rs-8460839/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8460839/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eIntroduction: Acute mesenteric ischemia (AMI) is a rare and life-threatening condition that leads to intestinal necrosis. Accurate assessment of intestinal viability and perfusion is crucial for reducing its high mortality rate.\u003c/p\u003e \u003cp\u003eCase Presentation: A 65-year-old female patient diagnosed with acute mesenteric ischemia complicated by intestinal necrosis underwent exploratory laparotomy. Under indocyanine green (ICG) imaging guidance, the necrotic bowel segments were resected. Postoperative quantitative analysis and histopathology confirmed intestinal necrosis.\u003c/p\u003e \u003cp\u003eDiscussion: Due to the lack of specific appearance in the early stages of intestinal wall necrosis caused by acute mesenteric ischemia, relying solely on white light or subjective qualitative ICG fluorescence imaging makes it difficult to precisely define the resection margin. This case innovatively applied quantitative ICG fluorescence analysis, revealing a correspondence between specific perfusion parameters, including T\u003csub\u003e0\u003c/sub\u003e and slope, and the histopathological grading of intestinal necrosis. This demonstrates that quantitative ICG may provide surgeons with an objective intraoperative decision-making tool.\u003c/p\u003e \u003cp\u003eConclusion: This case demonstrates that ICG fluorescence imaging combined with quantitative analysis has the potential to serve as an effective method for objectively assessing intestinal viability.\u003c/p\u003e","manuscriptTitle":"From Intraoperative Visual Inspection to Postoperative Quantification: ICG Fluorescence Angiography for Acute Mesenteric Ischemia Validated by Histopathology","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-03 15:57:25","doi":"10.21203/rs.3.rs-8460839/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-03-16T16:22:04+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-19T09:03:03+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-16T11:01:12+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"107845554780166224206982544766360807591","date":"2026-02-14T10:51:13+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"194517564075069407771269459935177220830","date":"2026-02-11T22:30:53+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-10T07:42:07+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"334354010918556452153817470303660690049","date":"2026-02-09T08:37:13+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"261146434786715233837930096351851884937","date":"2026-02-02T10:05:44+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"21854989113442825939866845834462479157","date":"2026-01-30T13:22:55+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-01-30T10:05:45+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-12-31T18:51:08+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-12-29T06:17:31+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-12-29T06:17:26+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Surgery","date":"2025-12-27T11:36:47+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-surgery","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bsur","sideBox":"Learn more about [BMC Surgery](http://bmcsurg.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bsur/default.aspx","title":"BMC Surgery","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"e88ee5b1-f6ed-4cfb-9f1b-ffac258c328b","owner":[],"postedDate":"February 3rd, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-07T13:53:24+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-03 15:57:25","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8460839","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8460839","identity":"rs-8460839","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}