Terminal ileal intubation is not recommended in routine colonoscopy: data from a large-scale retrospective study

Terminal ileal intubation is not recommended in routine colonoscopy: data from a large-scale retrospective 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 Research Article Terminal ileal intubation is not recommended in routine colonoscopy: data from a large-scale retrospective study Shunqing Shu, Chen Zhang, Liu Liu, Jing Shan, Tong Xiang, Tao Shu, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4875836/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 26 Nov, 2024 Read the published version in BMC Gastroenterology → Version 1 posted 4 You are reading this latest preprint version Abstract Background Terminal ileal intubation (TII) demonstrates a complete colonoscopy, but whether it should be performed in routine colonoscopies remains uncertain. We aimed to explore the diagnostic yield of TII in routine colonoscopy and investigate the association of TII and the detection of lesion. Methods We conducted a retrospective study included patients who underwent colonoscopy with cecal intubation at our endoscopic center between November 1 2022 and July 31 2023. Macroscopic and histologic findings of terminal ileum were recorded. We used propensity score matching to adjust for differences between groups and further analyzed the difference of polyp detection rate (PDR), adenoma detection rate (ADR), sessile serrated lesion detection rate (SSDR) and right-sided lesion detection rate between patients underwent TII or not. Results There were 13372 patients with cecal intubation colonoscopy, including 7599 (56.8%) with TII and 5773 (43.2%) without TII. Abnormal endoscopic findings were observed in 150 of 7599 unselected individuals and only 7 of these cases were regarded as pathologically significant. Likewise, abnormal endoscopic findings were found in 20 of 1494 asymptomatic individuals with 19 nonspecific ileitis determined by histopathology. After PSM, there were no significant differences in PDR (51.5% vs 50.8%, P = 0.506), ADR (31.3% vs 30.0%, P = 0.156), SSDR (1.7% vs 1.8%, P = 0.613) and right-sided lesion detection rate (16.5% vs 16.5%, P = 1.000) between the two groups. Conclusion TII was not proposed in routine colonoscopy, owing to the limited diagnostic value and lack of superiority on lesion detection. terminal ileal intubation cecal intubation colonoscopy diagnostic value lesion detection rate Figures Figure 1 Introduction Colonoscopy is an effective procedure for reducing colorectal cancer (CRC) incidence and mortality( 1 ). Complete visualization of the colorectum is the prerequisite for accurate diagnosis and reliable exclusion of disease༈2, 3༉. Therefore, cecal intubation is required in routine colonoscopy and cecal intubation rate (CIR) has been established as one of the quality control indicators of colonoscopy༈2༉. Terminal ileum intubation (TII) is regarded as the gold standard of successful cecal intubation༈4༉. However, whether the TII should be performed in routine colonoscopies remains unclear. TII is technically feasible in almost of all patients undergoing colonoscopy( 5 ). However, the practice of ileal intubation varies widely, ranging from 12–96% in the previous literatures༈5༉. In some centers, endoscopists tend to attempt ileal intubation to demonstrate the complete visualization of colon or maintain the endoscopic skills༈6༉. Meanwhile, other studies also reported the reasons why this procedure was not routinely performed, such as intubation difficulty, patient intolerance, additional time requirement༈7༉. The decision for TII mostly depends on endoscopists, lack of guidelines recommendations. The diagnostic yield of TII in symptomatic patients especially diarrhea individuals has been reported in some studies( 7 ). However, its benefit for unselected or asymptomatic individuals reached diverse conclusions. Some researchers have reported very high ileal intubation rates with an appreciable extra diagnostic yield, while others have found routine ileal intubation unrewarding due to its limit positive findings༈8༉. In addition, whether TII is beneficial to the lesion detection remains unclear. Theoretically, the time spent in the proximal colon deflecting folds during attempts of TII may reveal previously unnoticed polyps or adenomas༈9༉. And it was reported that endoscopists who frequently performed ileal intubation seemed to have higher detection rate of adenoma or sessile serrated lesion༈10༉. However, evidence on the association between TII and PDR or ADR are limited and remain to be further established. We therefore aimed to analyze the diagnostic yield of TII in routine colonoscopy both in unselected and asymptomatic individuals and investigated the influence of TII on the lesion detection rate. Methods Patients We retrospectively enrolled patients who underwent colonoscopy at the endoscopic center of The Third People’s Hospital of Chengdu from November 1, 2022 to July 31 2023. Patients with an unavoidable reason for failure to reach the cecum were excluded. Data including patient age, sex, body mass index (BMI), quality of bowel preparation, endoscopic and histopathological findings were retrieved from the electronic database. Written informed consent was obtained from each patient. Colonoscopy All colonoscopies were performed by experienced endoscopists who performed at least 500 colonoscopies and 200 ileal intubations. All patients were provided with standard verbal and written diet and bowel cleansing instructions before the procedure. Routine bowel preparation was polyethylene glycol-based regimen. The quality of bowel cleansing was evaluated by Boston Bowel Preparation Scale (BBPS). At our center, ileal intubation is not routinely performed and it depends on endoscopists. But representative photographs of cecal landmarks were required to taken such as the terminal ileum, ileocecal valve, or the appendiceal orifice to confirm the procedure completeness. Propensity score-matching (PSM) analysis To investigate the impact of TII on lesion detection rate, we collected information on polyp detection rate (PDR), adenoma detection rate (ADR), sessile serrated lesion detection rate (SSDR) and right-sided lesion detection rate by the group with or without TII. PSM analysis was conducted to avoid potential bias using known clinically relevant confounders including age, sex, source, BMI, bowel preparation that may affect the lesion detection rate. One-to-one nearest neighbour matching without replacement was performed with a maximum caliper of 0.01 which was the proposed optimal setting. The resulting propensity score-matched pairs were used in subsequent analyses. Statistical analysis Multiple imputation was used to deal with the missing data of BMI. Continuous variables are reported as medians (ranges) and analyzed with the Student’s t test or Mann-Whitney U test. Categorical variables are presented as frequencies and percentages, which were compared by using the Pearson test or the Fisher exact test, as appropriate. Statistical analyses were performed by using IBM SPSS Statistics (version 26, Chicago, IL, USA). Statistical significance was defined as P -value < 0.05. Results Of the 13832 colonoscopies enrolled during the study period, 460 failed to reach cecum were excluded for the following reasons: inadequate bowel preparation in 180 subjects, stricture caused by tumor or other reasons in 138 subjects, history of right-sided colon surgery in 69 subjects, endoscopic treatments such as endoscopic submucosal dissection (ESD) or endoscopic hemostasis in 29 subjects, intubation difficulty in 29 subjects, retained blood in 7 subjects and intolerance in 8 subjects (Figure 1). The remaining 13372 subjects achieved cecal intubation and fulfilled all the other study criteria were enrolled, suggesting 96.7% of CIR in our center. The median age of the total 13372 subjects was 54 year (range 43-63 year) with 6437 men (48.1%). Of them, successful ileal intubation was achieved in 7599 (56.8%) subjects. The rate of adequate bowel preparation rate was 89.8%. Baseline characteristics of the two groups were presented in Table 4. Macroscopic and histologic findings A total of 150 out of 7599 subjects who had successful intubation into the terminal ileum showed macroscopic abnormalities on the terminal ileum. As presented in Table 1, the abnormal endoscopic findings included erosion/ulcer (115 cases, 76.7%), hyperemic/edematous appearance (18 cases, 12.0%), polypoid or protruding lesion (13 cases, 8.7%), stenosis (1 case, 0.6%). Biopsies were obtained in 135 patients out of 150 with macroscopic abnormalities on the terminal ileum. The leading pathologic findings in these patients were chronic/acute ileitis (124 cases, 82.7%), which were nonspecific and considered not to be clinically significant. Other histopathologic findings with clinical significance were observed in 7 cases, including tuberculosis in 1 case, inflammatory bowel disease in 2 cases, Behcet’s disease in 1 case, lymphoma in 1 case and ulcer in 2 cases (Table 2). In short, the diagnosis and treatment were adjusted after TII only in 7 of 7599 subjects. We further analyzed the diagnostic value of TII in asymptomatic subjects, reporting 1494 ileal intubation in 2533 asymptomatic subjects. Of them, abnormal ileal mucosa was observed in 20 subjects, including erosion/ulcer (17 cases), hyperemic/edematous mucosa (2 cases), and polypoid/protruding lesion (1 cases). Histopathological evaluation revealed nonspecific ileitis in 19 subjects and polypoid hyperplasia in only 1 subject (Table 3). Lesion detection rate by TII After 1:1 PSM, the analyses were restricted to 5552 participants in TII group and 5552 in No TII group. There were no statistical differences in age, sex, the proportion of inpatients, body mass index (BMI) and the rate of adequate bowel preparation between the groups after matching (Table 4). Before PSM, higher detection rate of polyp (52.0% vs 47.0%), adenoma (31.7% vs 27.4%) and right-sided lesion (17.0% vs 14.4%) were observed in No TII group. However, analysis of the results obtained in the matching cohort demonstrated that no significant difference exists in PDR (51.5% vs 50.8%, P =0.506), ADR (31.3% vs 30.0%, P =0.156), SSDR (1.7% vs 1.8%, P =0.613) and right-sided lesion detection rate (16.5% vs 16.5%, P =1.000). Discussion In our study, clinically significant histopathology was obtained only 7 of 7599 unselected subjects with ileal intubation and even none of case in asymptomatic individuals, suggesting a low diagnostic yield for ileum intubation both in unselected and asymptomatic population. Additionally, TII was not associated with higher detection rate of polyp, adenoma, sessile serrated lesion or right-sided lesion, which further indicated the unnecessity of TII in routine colonoscopy. The reported diagnostic yield of ileum intubation during colonoscopy was variable among different populations and indications for the procedure. Geboes et al., reported endoscopic and histological ileal abnormalities in 48% of their patients with suspected symptoms of IBD( 11 ). In addition, the value of TII has been demonstrated in the evaluation of diarrhea, with a positive diagnostic yield of 18–34%༈12, 13༉. Other studies have reported a more modest but still significant yield in such patients༈14༉. However, these studies were restricted to highly selected patients and the current evidence in unselected individuals is scarce. Meral et al. suggested that clinically significant histopathological findings were observed in only 2.1% (22/1032) of all patients who underwent TII regardless of the indication༈7༉. Likewise, in our study, ileal intubation revealed endoscopically abnormal mucosa in nearly 2% (150/7599) of patients in unselected individuals and only 0.09% (7/7599) of these cases were deemed as pathologically significant, which suggested a low diagnostic yield of ileal inspection. Importantly, by incorporating a great number of subjects in an observation real-world fashion, our study offers more dependable findings. In asymptomatic patients, ileoscopy appears to have an even lower yield. In a retrospective study based on patients without significant gastrointestinal symptoms, endoscopic abnormalities were noted in 3.7% of patients who underwent ileal intubation. However, in only around half of these cases (1.8%), the pathological findings were regarded to be clinically significant༈15༉. Consistent with this study, our study identified abnormal endoscopic findings in 1.3% (20/1494) of the asymptomatic individuals, suggesting a limited value of ileal inspection in asymptomatic individuals. Of note, the main microscopic findings in these cases in our study were nonspecific ileitis. More importantly, in 89.4% (17/19) of patients, ileal abnormalities were isolated without colitis or proctitis, which was proved not to evolve into Crohn’s disease on follow-up or affect the clinical management༈16, 17༉. As more asymptomatic subjects are likely to engage in colonoscopy screening due to the raised awareness of CRC screening, the necessity of routine TII would be further challenged. Cecal intubation rates has be established as one of the performance measures for colonoscopy as lower cecal intubation rates are associated with diminished detection of neoplasia and higher incidence of interval CRC( 3 ). However, whether ileum intubation could further improve the detection of polyps or adenomas was unclear. It was suggested that attempts at terminal ileum intubation may help to detect hidden lesions which may increase ADR༈9༉. However, in our study, we found no significant difference on PDR or ADR whether the TI was intubated or not. Likewise, Leiman et al. reported that TII was not associated with PDR or ADR༈10༉. Of note, this study involved only patients who underwent screening colonoscopies, which may be difficult to extrapolate to unselected population. Inversely, Wang et al. reported that TI intubation has a lower PDR compared with non-TI intubation group༈18༉. This discrepancy may be ascribed to the imbalance of baseline characteristics with more asymptomatic cases in TI group in study by Wang et al༈18༉. In addition, the overall ADR (16%), PDR (27%) in this study is significantly lower than those in our study or other previous studies, which was far from the international standards. In contrast, we used PSM to adjust for differences in baseline characteristics, reporting relatively higher ADR (47.0–52.0%) and PDR (27.4–31.7%) in both groups, which provided more convinced results. It was expected that ileum intubation had the potential for improving lesion detection in right-sided colon due to the increased attention to the right colon, but this was not seen in our study. Similarly, a study by Buerger et al. indicated that ileal intubation was not associated with higher detection rates for adenomas and serrated polyps in the right-sided colon compared to cecal intubation༈19༉. According to Klare et al.༈20༉, duration of mucosa observation was associated with adenoma detection in the proximal colon but a minimum time span of at least 4 min was found to be sufficient for proximal adenoma detection, which may explain the negative findings in these two studies. Although TII has not been listed as one of colonoscopy quality indicators, several studies proposed a dedicated attempt to intubate terminal ileal in all colonoscopies, irrespective indication, to provide more convincing evidence of total colonic evaluation( 6 , 21 ). However, our findings tended to tune down the value of TII. First, although macroscopic abnormality on the terminal ileum was found in 150 patients, histopathologic findings in most of them were not significant for clinical practice. Only 7 subjects benefit from the findings by TII, which gave as low as 0.09% diagnostic yield for all ileoscopies reported in the present study. Second, our data suggested that ileal intubation was not superior to cecal intubation in terms of PDR, ADR, SSLR in the entire colon or right-sided lesion detection. Our findings extend the results of previous reports, with a large number of patients and real-world setting, not only to evidence the limit diagnostic value of TII both in unselected and asymptomatic subjects, but also to show TII did not improve lesion detection either in entire colon or right-sided colon, which did not support that ileal intubation was routinely performed as part of colonoscopy. Some limitation of our study should be considered while interpreting the results. First, this was a single center and retrospective study, we cannot eliminate potential selection bias. Second, although PSM was used in our study to avoid the bias from baseline characteristics between the two groups, unmeasured confounders may also exist. Third, withdrawal time was not measured in this study. However, in our center, policies for colonoscopy quality control were used to keep the colonoscopic withdrawal time within the recommended limits. Fourth, there are currently no uniform standards for “abnormal” endoscopic or microscopic findings of terminal ileum, which may partly explain the varied diagnostic value of ileal intubation in previous studies. However, standards based on the consensus of experienced endoscopists and pathologists were used in our center to reduce the potential bias. Fifth, although we found ileal intubation did not increase ADR or SSDR, its effect on the subsequent risk of CRC was not evaluated in our study or other study( 10 ). Further studies with prospective-design and long-term follow-up are needed to address this issue. In summary, results derived from our study show that ileal intubation has a low diagnostic value for unselected or asymptomatic individuals. Furthermore, ileal intubation may not provide any benefit over cecal intubation concerning the lesion detection. We therefore propose not to perform ileal intubation in routine colonoscopy except in patients with clinical suspicion of ileal disease. Abbreviations CRC：colorectal cancer CIR：cecal intubation rate TII：Terminal ileum intubation BMI：body mass index PSM：propensity score-matching BBPS: Boston bowel preparation scale PDR: polyp detection rate ADR: adenoma detection rate SSDR: sessile serrated lesion detection rate Declarations Acknowledgements: Not applicable. Authors' contributions: SSQ and ZC contributed to conception of the study, statistical analysis, interpretation of data and manuscript draft. LL and SJ contributed to colonoscopy operation, assessment and interpretation of data. XT and ST contributed to collection and analysis of data. SXB contributed to conception of the study, supervision, statistical analysis, interpretation of the data and revision of the report. All authors have approved the final draft of the manuscript. Funding: Not applicable. Date availability : All data generated or analyzed during this study are included in this published article. Ethics approval and consent to participate: The study was conducted in accordance with the tenets of the Declaration of Helsinki. Informed consent was waived by our Institutional Review Board because of the anonymous data and the retrospective nature of our study. Consent for publication: Not applicable. Competing interests: The authors declare that they have no competing interests. References Zhang J, Chen G, Li Z, et al. Colonoscopic screening is associated with reduced Colorectal Cancer incidence and mortality: a systematic review and meta-analysis. J Cancer 2020;11:5953-5970. Kaminski MF, Thomas-Gibson S, Bugajski M, et al. Performance measures for lower gastrointestinal endoscopy: a European Society of Gastrointestinal Endoscopy (ESGE) Quality Improvement Initiative. Endoscopy 2017;49:378-397. Keswani RN, Crockett SD, Calderwood AH. AGA Clinical Practice Update on Strategies to Improve Quality of Screening and Surveillance Colonoscopy: Expert Review. Gastroenterology 2021;161:701-711. Tang SJ, Wu R. Ilececum: A Comprehensive Review. Can J Gastroenterol Hepatol 2019;2019:1451835. Alkhatib AA, Fitzmaurice GM, Kumar S. Impact of pediatric versus adult colonoscope on terminal ileum intubation: a retrospective study. Ann Gastroenterol 2022;35:169-176. Powell N, Hayee BH, Yeoh DP, et al. Terminal ileal photography or biopsy to verify total colonoscopy: does the endoscope agree with the microscope? Gastrointest Endosc 2007;66:320-5. Meral M, Bengi G, Kayahan H, et al. Is ileocecal valve intubation essential for routine colonoscopic examination? Eur J Gastroenterol Hepatol 2018;30:432-437. Iacopini G, Frontespezi S, Vitale MA, et al. Routine ileoscopy at colonoscopy: a prospective evaluation of learning curve and skill-keeping line. Gastrointest Endosc 2006;63:250-6. Al-Sohaily S, Leong RW. The yield of ileoscopy at colonoscopy. J Gastroenterol Hepatol 2008;23:4-5. Leiman DA, Jawitz NG, Lin L, et al. Terminal ileum intubation is not associated with colonoscopy quality measures. J Gastroenterol Hepatol 2020;35:1503-1508. Geboes K, Ectors N, D'Haens G, et al. Is ileoscopy with biopsy worthwhile in patients presenting with symptoms of inflammatory bowel disease? Am J Gastroenterol 1998;93:201-6. Morini S, Lorenzetti R, Stella F, et al. Retrograde ileoscopy in chronic nonbloody diarrhea: a prospective, case-control study. Am J Gastroenterol 2003;98:1512-5. Zwas FR, Bonheim NA, Berken CA, et al. Diagnostic yield of routine ileoscopy. Am J Gastroenterol 1995;90:1441-3. Cherian S, Singh P. Is routine ileoscopy useful? An observational study of procedure times, diagnostic yield, and learning curve. Am J Gastroenterol 2004;99:2324-9. Alkhatib AA, Kumar S. Clinical Yield of Ileal Intubation During Screening Colonoscopy. Cureus 2022;14:e20870. Koureta E, Karatzas P, Tampaki M, et al. Isolated nonspecific terminal ileitis: prevalence, clinical evolution and correlation with metachronous diagnosis of Crohn's disease: a retrospective study and review of the literature. Ann Gastroenterol 2024;37:199-205. Courville EL, Siegel CA, Vay T, et al. Isolated asymptomatic ileitis does not progress to overt Crohn disease on long-term follow-up despite features of chronicity in ileal biopsies. Am J Surg Pathol 2009;33:1341-7. Wang W, Chen K, Xu Y, et al. Routine ileal intubation in colonoscopy does not increase the polyp detection rate: a retrospective study. Z Gastroenterol 2020;58:955-959. Buerger M, Kasper P, Allo G, et al. Ileal intubation is not associated with higher detection rate of right-sided conventional adenomas and serrated polyps compared to cecal intubation after adjustment for overall adenoma detection rate. BMC Gastroenterol 2019;19:190. Klare P, Phlipsen H, Haller B, et al. Longer observation time increases adenoma detection in the proximal colon - a prospective study. Endosc Int Open 2017;5:E1289-e1298. Powell N, Knight H, Dunn J, et al. Images of the terminal ileum are more convincing than cecal images for verifying the extent of colonoscopy. Endoscopy 2011;43:196-201. Tables Table1: Abnormal endoscopic findings of ileal mucosa in unselected subjects Endoscopic findings N (%) Erosion/ulcer 115 (76.7%) Hyperemic/edematous mucosa 18 (12.0%) Polypoid or protruding lesion 13 (8.7%) Stenosis 1 (0.6%) other 3 (2.0%) Total 150 Table2: Pathologic findings of ileal mucosa in unselected subjects Pathologic findings N Chronic/acute ileitis 124 Normal mucosa 2 Tuberculosis 1 Inflammatory bowel disease 2 Behcet’s disease 1 Ulcer 2 Lymphoma 1 No biopsy or Other lesion 17 Table 3: Endoscopic and pathologic findings of ileal mucosa in asymptomatic subjects Endoscopic findings N Pathologic findings N Erosion/ulcer 17 Nonspecific ileitis 19 Hyperemic/edematous mucosa 2 Polypoid hyperplasia 1 Polypoid or protruding lesion 1 Table 4: Baseline characteristics and clinical outcome of patients before and after matching Before matching P value After matching P value TII (n=7599) No TII (n=5773) TII (n=5552) No TII (n=5552) Median Age, y (interquartile range) 53 (41, 61) 57 (48, 66) 0.000 55 (46, 64) 56 (47, 65) 0.055 Sex (male, n%) 47.3% 49.3% 0.019 47.4% 49.0% 0.095 Inpatient (n%) 34.1% 41.1% 0.000 38.7% 39.5% 0.371 Body mass index, kg/m 2 (interquartile range) 23.05 (20.96, 25.33) 23.44 (21.22, 25.71) 0.000 22.89 (20.63, 25.06) 23.02 (20.57, 25.16) 0.298 Adequate bowel preparation (n%) 91.7% 87.3% 0.000 89.5% 88.9% 0.258 Polyp detection rate (n%) 47.0% 52.0% 0.000 50.8% 51.5% 0.506 Adenoma detection rate (n%) 27.4% 31.7% 0.000 30.0% 31.3% 0.156 Sessile serrated lesion detection rate (n%) 1.7% 1.7% 0.846 1.8% 1.7% 0.613 Right-sided lesion detection rate (n%) 14.4% 17.0% 0.000 16.5% 16.5% 1.000 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 26 Nov, 2024 Read the published version in BMC Gastroenterology → Version 1 posted Editorial decision: Revision requested 09 Aug, 2024 Editor assigned by journal 09 Aug, 2024 Submission checks completed at journal 09 Aug, 2024 First submitted to journal 07 Aug, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-4875836","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":338081631,"identity":"54cbf7e5-ea37-4077-ad37-1e65426c9a01","order_by":0,"name":"Shunqing Shu","email":"","orcid":"","institution":"Affiliated Hospital of Southwest Medical University","correspondingAuthor":false,"prefix":"","firstName":"Shunqing","middleName":"","lastName":"Shu","suffix":""},{"id":338081632,"identity":"81831d87-aff7-440d-bd85-1d5c0bfd4ad4","order_by":1,"name":"Chen Zhang","email":"","orcid":"","institution":"The Third People’s Hospital of Chengdu, The Affiliated Hospital of Southwest Jiaotong University","correspondingAuthor":false,"prefix":"","firstName":"Chen","middleName":"","lastName":"Zhang","suffix":""},{"id":338081633,"identity":"9cf6f59b-fda4-44df-9f2b-2749b38843a8","order_by":2,"name":"Liu Liu","email":"","orcid":"","institution":"The Third People’s Hospital of Chengdu, The Affiliated Hospital of Southwest Jiaotong University","correspondingAuthor":false,"prefix":"","firstName":"Liu","middleName":"","lastName":"Liu","suffix":""},{"id":338081634,"identity":"fe4a85d1-9019-42d9-a24c-ecdf254e9c9a","order_by":3,"name":"Jing Shan","email":"","orcid":"","institution":"The Third People’s Hospital of Chengdu, The Affiliated Hospital of Southwest Jiaotong University","correspondingAuthor":false,"prefix":"","firstName":"Jing","middleName":"","lastName":"Shan","suffix":""},{"id":338081635,"identity":"dece8181-d8ba-42f5-af5e-7b531fe5a0c1","order_by":4,"name":"Tong Xiang","email":"","orcid":"","institution":"The Third People’s Hospital of Chengdu, The Affiliated Hospital of Southwest Jiaotong University","correspondingAuthor":false,"prefix":"","firstName":"Tong","middleName":"","lastName":"Xiang","suffix":""},{"id":338081636,"identity":"737dacd6-415e-4e00-8bcd-40aa6737dcd2","order_by":5,"name":"Tao Shu","email":"","orcid":"","institution":"The Third People’s Hospital of Chengdu, The Affiliated Hospital of Southwest Jiaotong University","correspondingAuthor":false,"prefix":"","firstName":"Tao","middleName":"","lastName":"Shu","suffix":""},{"id":338081637,"identity":"31123d10-9780-4c9c-8136-0b0eee1d4ba6","order_by":6,"name":"Xiaobin Sun","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAxklEQVRIiWNgGAWjYDACCRBhICFnf7yx8eEH4rUUWBgznDncbCxBvJYPFYkNN9LbBHiI0WFwu/2ZdIGBRGLjzIdtQP12croNBLRIzjljJj3DQMK4WTqx7UEBQ7Kx2QECWvglctikeQwkZNukE9sNJBgOJG4jpIVNIv0ZSAtjj+TBNgkeYrTwSySYgbQozpBgJFIL0C/G1kAtxgY8icBANiDCL8AQe3ib50+dnAH78YcPP1TYyRHUgm4CacpHwSgYBaNgFOAAAIOcPAVYk7XIAAAAAElFTkSuQmCC","orcid":"","institution":"Affiliated Hospital of Southwest Medical University","correspondingAuthor":true,"prefix":"","firstName":"Xiaobin","middleName":"","lastName":"Sun","suffix":""}],"badges":[],"createdAt":"2024-08-07 15:29:37","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4875836/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4875836/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12876-024-03521-3","type":"published","date":"2024-11-26T15:57:35+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":65787616,"identity":"0f13e2de-9e59-4e71-801d-303457a08be5","added_by":"auto","created_at":"2024-10-02 16:43:15","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":27951,"visible":true,"origin":"","legend":"\u003cp\u003eStudy flow diagram.\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-4875836/v1/057204a61cf6ec4e8dfcb321.png"},{"id":70382677,"identity":"d84cb99d-6fe1-4b7a-8d4d-70005be7955a","added_by":"auto","created_at":"2024-12-02 16:29:17","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":504056,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4875836/v1/cf51113e-62c7-4e3a-85f9-104e719243b6.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Terminal ileal intubation is not recommended in routine colonoscopy: data from a large-scale retrospective study","fulltext":[{"header":"Introduction","content":"\u003cp\u003eColonoscopy is an effective procedure for reducing colorectal cancer (CRC) incidence and mortality(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). Complete visualization of the colorectum is the prerequisite for accurate diagnosis and reliable exclusion of disease༈2, 3༉. Therefore, cecal intubation is required in routine colonoscopy and cecal intubation rate (CIR) has been established as one of the quality control indicators of colonoscopy༈2༉. Terminal ileum intubation (TII) is regarded as the gold standard of successful cecal intubation༈4༉. However, whether the TII should be performed in routine colonoscopies remains unclear.\u003c/p\u003e \u003cp\u003eTII is technically feasible in almost of all patients undergoing colonoscopy(\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). However, the practice of ileal intubation varies widely, ranging from 12\u0026ndash;96% in the previous literatures༈5༉. In some centers, endoscopists tend to attempt ileal intubation to demonstrate the complete visualization of colon or maintain the endoscopic skills༈6༉. Meanwhile, other studies also reported the reasons why this procedure was not routinely performed, such as intubation difficulty, patient intolerance, additional time requirement༈7༉. The decision for TII mostly depends on endoscopists, lack of guidelines recommendations.\u003c/p\u003e \u003cp\u003eThe diagnostic yield of TII in symptomatic patients especially diarrhea individuals has been reported in some studies(\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e). However, its benefit for unselected or asymptomatic individuals reached diverse conclusions. Some researchers have reported very high ileal intubation rates with an appreciable extra diagnostic yield, while others have found routine ileal intubation unrewarding due to its limit positive findings༈8༉. In addition, whether TII is beneficial to the lesion detection remains unclear. Theoretically, the time spent in the proximal colon deflecting folds during attempts of TII may reveal previously unnoticed polyps or adenomas༈9༉. And it was reported that endoscopists who frequently performed ileal intubation seemed to have higher detection rate of adenoma or sessile serrated lesion༈10༉. However, evidence on the association between TII and PDR or ADR are limited and remain to be further established.\u003c/p\u003e \u003cp\u003eWe therefore aimed to analyze the diagnostic yield of TII in routine colonoscopy both in unselected and asymptomatic individuals and investigated the influence of TII on the lesion detection rate.\u003c/p\u003e "},{"header":"Methods","content":"\u003cp\u003e\u003cstrong\u003ePatients\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe retrospectively enrolled patients who underwent colonoscopy at the endoscopic center of The Third People\u0026rsquo;s Hospital of Chengdu from November 1, 2022 to July 31 2023. Patients with an unavoidable reason for failure to reach the cecum were excluded. Data including patient age, sex, body mass index (BMI), quality of bowel preparation, endoscopic and histopathological findings were retrieved from the electronic database. Written informed consent was obtained from each patient.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eColonoscopy\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll colonoscopies were performed by experienced endoscopists who performed at least 500 colonoscopies and 200 ileal intubations. All patients were provided with standard verbal and written diet and bowel cleansing instructions before the procedure. Routine bowel preparation was polyethylene glycol-based regimen. The quality of bowel cleansing was evaluated by Boston Bowel Preparation Scale (BBPS). At our center, ileal intubation is not routinely performed and it depends on endoscopists. But representative photographs of cecal landmarks were required to taken such as the terminal ileum, ileocecal valve, or the appendiceal orifice to confirm the procedure completeness.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePropensity score-matching (PSM) analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTo investigate the impact of TII on lesion detection rate, we collected information on polyp detection rate (PDR), adenoma detection rate (ADR), sessile serrated lesion detection rate (SSDR) and right-sided lesion detection rate by the group with or without TII. PSM analysis was conducted to avoid potential bias using known clinically relevant confounders including age, sex, source, BMI, bowel preparation that may affect the lesion detection rate. One-to-one nearest neighbour matching without replacement was performed with a maximum caliper of 0.01 which was the proposed optimal setting. The resulting propensity score-matched pairs were used in subsequent analyses.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eMultiple imputation was used to deal with the missing data of BMI. Continuous variables are reported as medians (ranges) and analyzed with the Student\u0026rsquo;s t test or Mann-Whitney U test. Categorical variables are presented as frequencies and percentages, which were compared by using the Pearson\u0026nbsp;\u0026nbsp;test or the Fisher exact test, as appropriate. Statistical analyses were performed by using IBM SPSS Statistics (version 26, Chicago, IL, USA). Statistical significance was defined as \u003cem\u003eP\u003c/em\u003e-value \u0026lt; 0.05.\u0026nbsp;\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eOf the 13832 colonoscopies enrolled during the study period, 460 failed to reach cecum were excluded for the following reasons: inadequate bowel preparation in 180 subjects, stricture caused by tumor or other reasons in 138 subjects, history of right-sided colon surgery in 69 subjects, endoscopic treatments such as endoscopic submucosal dissection (ESD) or endoscopic hemostasis in 29 subjects, intubation difficulty in 29 subjects, retained blood in 7 subjects and intolerance in 8 subjects (Figure 1). The remaining 13372 subjects achieved cecal intubation and fulfilled all the other study criteria were enrolled, suggesting 96.7% of CIR in our center.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe median age of the total 13372 subjects was 54 year (range 43-63 year) with 6437 men (48.1%). Of them, successful ileal intubation was achieved in 7599 (56.8%) subjects. The rate of adequate bowel preparation rate was 89.8%. Baseline characteristics of the two groups were presented in Table 4.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMacroscopic and histologic findings\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA total of 150 out of 7599 subjects who had successful intubation into the terminal ileum showed macroscopic abnormalities on the terminal ileum. As presented in Table 1, the abnormal endoscopic findings included erosion/ulcer (115 cases, 76.7%), hyperemic/edematous appearance (18 cases, 12.0%), polypoid or protruding lesion (13 cases, 8.7%), stenosis (1 case, 0.6%). Biopsies were obtained in 135 patients out of 150 with macroscopic abnormalities on the terminal ileum. The leading pathologic findings in these patients were chronic/acute ileitis (124 cases, 82.7%), which were nonspecific and considered not to be clinically significant. Other histopathologic findings with clinical significance were observed in 7 cases, including tuberculosis in 1 case, inflammatory bowel disease in 2 cases, Behcet\u0026rsquo;s disease in 1 case, lymphoma in 1 case and ulcer in 2 cases (Table 2). In short, the diagnosis and treatment were adjusted after TII only in 7 of 7599 subjects.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eWe further analyzed the diagnostic value of TII in asymptomatic subjects, reporting 1494 ileal intubation in 2533 asymptomatic subjects. Of them, abnormal ileal mucosa was observed in 20 subjects, including erosion/ulcer (17 cases), hyperemic/edematous mucosa (2 cases), and polypoid/protruding lesion (1 cases). Histopathological evaluation revealed nonspecific ileitis in 19 subjects and polypoid hyperplasia in only 1 subject (Table 3).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eLesion detection rate by TII\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAfter 1:1 PSM, the analyses were restricted to 5552 participants in TII group and 5552 in No TII group. There were no statistical differences in age, sex, the proportion of inpatients, body mass index (BMI) and the rate of adequate bowel preparation between the groups after matching (Table 4). Before PSM, higher detection rate of polyp (52.0% vs 47.0%), adenoma (31.7% vs 27.4%) and right-sided lesion (17.0% vs 14.4%) were observed in No TII group. However, analysis of the results obtained in the matching cohort demonstrated that no significant difference exists in PDR (51.5% vs 50.8%, \u003cem\u003eP\u003c/em\u003e=0.506), ADR (31.3% vs 30.0%, \u003cem\u003eP\u003c/em\u003e=0.156), SSDR (1.7% vs 1.8%, \u003cem\u003eP\u003c/em\u003e=0.613) and right-sided lesion detection rate (16.5% vs 16.5%, \u003cem\u003eP\u003c/em\u003e=1.000).\u0026nbsp;\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn our study, clinically significant histopathology was obtained only 7 of 7599 unselected subjects with ileal intubation and even none of case in asymptomatic individuals, suggesting a low diagnostic yield for ileum intubation both in unselected and asymptomatic population. Additionally, TII was not associated with higher detection rate of polyp, adenoma, sessile serrated lesion or right-sided lesion, which further indicated the unnecessity of TII in routine colonoscopy.\u003c/p\u003e \u003cp\u003eThe reported diagnostic yield of ileum intubation during colonoscopy was variable among different populations and indications for the procedure. Geboes et al., reported endoscopic and histological ileal abnormalities in 48% of their patients with suspected symptoms of IBD(\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e). In addition, the value of TII has been demonstrated in the evaluation of diarrhea, with a positive diagnostic yield of 18\u0026ndash;34%༈12, 13༉. Other studies have reported a more modest but still significant yield in such patients༈14༉. However, these studies were restricted to highly selected patients and the current evidence in unselected individuals is scarce. Meral et al. suggested that clinically significant histopathological findings were observed in only 2.1% (22/1032) of all patients who underwent TII regardless of the indication༈7༉. Likewise, in our study, ileal intubation revealed endoscopically abnormal mucosa in nearly 2% (150/7599) of patients in unselected individuals and only 0.09% (7/7599) of these cases were deemed as pathologically significant, which suggested a low diagnostic yield of ileal inspection. Importantly, by incorporating a great number of subjects in an observation real-world fashion, our study offers more dependable findings. In asymptomatic patients, ileoscopy appears to have an even lower yield. In a retrospective study based on patients without significant gastrointestinal symptoms, endoscopic abnormalities were noted in 3.7% of patients who underwent ileal intubation. However, in only around half of these cases (1.8%), the pathological findings were regarded to be clinically significant༈15༉. Consistent with this study, our study identified abnormal endoscopic findings in 1.3% (20/1494) of the asymptomatic individuals, suggesting a limited value of ileal inspection in asymptomatic individuals. Of note, the main microscopic findings in these cases in our study were nonspecific ileitis. More importantly, in 89.4% (17/19) of patients, ileal abnormalities were isolated without colitis or proctitis, which was proved not to evolve into Crohn\u0026rsquo;s disease on follow-up or affect the clinical management༈16, 17༉. As more asymptomatic subjects are likely to engage in colonoscopy screening due to the raised awareness of CRC screening, the necessity of routine TII would be further challenged.\u003c/p\u003e \u003cp\u003eCecal intubation rates has be established as one of the performance measures for colonoscopy as lower cecal intubation rates are associated with diminished detection of neoplasia and higher incidence of interval CRC(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). However, whether ileum intubation could further improve the detection of polyps or adenomas was unclear. It was suggested that attempts at terminal ileum intubation may help to detect hidden lesions which may increase ADR༈9༉. However, in our study, we found no significant difference on PDR or ADR whether the TI was intubated or not. Likewise, Leiman et al. reported that TII was not associated with PDR or ADR༈10༉. Of note, this study involved only patients who underwent screening colonoscopies, which may be difficult to extrapolate to unselected population. Inversely, Wang et al. reported that TI intubation has a lower PDR compared with non-TI intubation group༈18༉. This discrepancy may be ascribed to the imbalance of baseline characteristics with more asymptomatic cases in TI group in study by Wang et al༈18༉. In addition, the overall ADR (16%), PDR (27%) in this study is significantly lower than those in our study or other previous studies, which was far from the international standards. In contrast, we used PSM to adjust for differences in baseline characteristics, reporting relatively higher ADR (47.0\u0026ndash;52.0%) and PDR (27.4\u0026ndash;31.7%) in both groups, which provided more convinced results. It was expected that ileum intubation had the potential for improving lesion detection in right-sided colon due to the increased attention to the right colon, but this was not seen in our study. Similarly, a study by Buerger et al. indicated that ileal intubation was not associated with higher detection rates for adenomas and serrated polyps in the right-sided colon compared to cecal intubation༈19༉. According to Klare et al.༈20༉, duration of mucosa observation was associated with adenoma detection in the proximal colon but a minimum time span of at least 4 min was found to be sufficient for proximal adenoma detection, which may explain the negative findings in these two studies.\u003c/p\u003e \u003cp\u003eAlthough TII has not been listed as one of colonoscopy quality indicators, several studies proposed a dedicated attempt to intubate terminal ileal in all colonoscopies, irrespective indication, to provide more convincing evidence of total colonic evaluation(\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e). However, our findings tended to tune down the value of TII. First, although macroscopic abnormality on the terminal ileum was found in 150 patients, histopathologic findings in most of them were not significant for clinical practice. Only 7 subjects benefit from the findings by TII, which gave as low as 0.09% diagnostic yield for all ileoscopies reported in the present study. Second, our data suggested that ileal intubation was not superior to cecal intubation in terms of PDR, ADR, SSLR in the entire colon or right-sided lesion detection. Our findings extend the results of previous reports, with a large number of patients and real-world setting, not only to evidence the limit diagnostic value of TII both in unselected and asymptomatic subjects, but also to show TII did not improve lesion detection either in entire colon or right-sided colon, which did not support that ileal intubation was routinely performed as part of colonoscopy.\u003c/p\u003e \u003cp\u003eSome limitation of our study should be considered while interpreting the results. First, this was a single center and retrospective study, we cannot eliminate potential selection bias. Second, although PSM was used in our study to avoid the bias from baseline characteristics between the two groups, unmeasured confounders may also exist. Third, withdrawal time was not measured in this study. However, in our center, policies for colonoscopy quality control were used to keep the colonoscopic withdrawal time within the recommended limits. Fourth, there are currently no uniform standards for \u0026ldquo;abnormal\u0026rdquo; endoscopic or microscopic findings of terminal ileum, which may partly explain the varied diagnostic value of ileal intubation in previous studies. However, standards based on the consensus of experienced endoscopists and pathologists were used in our center to reduce the potential bias. Fifth, although we found ileal intubation did not increase ADR or SSDR, its effect on the subsequent risk of CRC was not evaluated in our study or other study(\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e). Further studies with prospective-design and long-term follow-up are needed to address this issue.\u003c/p\u003e \u003cp\u003eIn summary, results derived from our study show that ileal intubation has a low diagnostic value for unselected or asymptomatic individuals. Furthermore, ileal intubation may not provide any benefit over cecal intubation concerning the lesion detection. We therefore propose not to perform ileal intubation in routine colonoscopy except in patients with clinical suspicion of ileal disease.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eCRC：colorectal cancer\u003c/p\u003e\n\u003cp\u003eCIR：cecal intubation rate\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTII：Terminal ileum intubation\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eBMI：body mass index\u0026nbsp;\u003c/p\u003e\n\u003cp\u003ePSM：propensity score-matching\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eBBPS: Boston bowel preparation scale\u003c/p\u003e\n\u003cp\u003ePDR: polyp detection rate\u003c/p\u003e\n\u003cp\u003eADR: adenoma detection rate\u003c/p\u003e\n\u003cp\u003eSSDR: sessile serrated lesion detection rate\u0026nbsp;\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements:\u0026nbsp;\u003c/strong\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026apos; contributions:\u003c/strong\u003e SSQ and ZC contributed to conception of the study, statistical analysis, interpretation of data and manuscript draft. LL and SJ contributed to colonoscopy operation, assessment and interpretation of data. XT and ST contributed to collection and analysis of data. SXB contributed to conception of the study, supervision, statistical analysis, interpretation of the data and revision of the report. All authors have approved the final draft of the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u0026nbsp;\u003c/strong\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDate availability\u003c/strong\u003e: All data generated or analyzed during this study are included in this published article.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate:\u0026nbsp;\u003c/strong\u003eThe study was conducted in accordance with the tenets of the Declaration of Helsinki. Informed consent was waived by our Institutional Review Board because of the anonymous data and the retrospective nature of our study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication:\u0026nbsp;\u003c/strong\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests:\u0026nbsp;\u003c/strong\u003eThe authors declare that they have no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eZhang J, Chen G, Li Z, et al. Colonoscopic screening is associated with reduced Colorectal Cancer incidence and mortality: a systematic review and meta-analysis. J Cancer 2020;11:5953-5970.\u003c/li\u003e\n\u003cli\u003eKaminski MF, Thomas-Gibson S, Bugajski M, et al. Performance measures for lower gastrointestinal endoscopy: a European Society of Gastrointestinal Endoscopy (ESGE) Quality Improvement Initiative. Endoscopy 2017;49:378-397.\u003c/li\u003e\n\u003cli\u003eKeswani RN, Crockett SD, Calderwood AH. AGA Clinical Practice Update on Strategies to Improve Quality of Screening and Surveillance Colonoscopy: Expert Review. Gastroenterology 2021;161:701-711.\u003c/li\u003e\n\u003cli\u003eTang SJ, Wu R. Ilececum: A Comprehensive Review. Can J Gastroenterol Hepatol 2019;2019:1451835.\u003c/li\u003e\n\u003cli\u003eAlkhatib AA, Fitzmaurice GM, Kumar S. Impact of pediatric versus adult colonoscope on terminal ileum intubation: a retrospective study. Ann Gastroenterol 2022;35:169-176.\u003c/li\u003e\n\u003cli\u003ePowell N, Hayee BH, Yeoh DP, et al. Terminal ileal photography or biopsy to verify total colonoscopy: does the endoscope agree with the microscope? Gastrointest Endosc 2007;66:320-5.\u003c/li\u003e\n\u003cli\u003eMeral M, Bengi G, Kayahan H, et al. Is ileocecal valve intubation essential for routine colonoscopic examination? Eur J Gastroenterol Hepatol 2018;30:432-437.\u003c/li\u003e\n\u003cli\u003eIacopini G, Frontespezi S, Vitale MA, et al. Routine ileoscopy at colonoscopy: a prospective evaluation of learning curve and skill-keeping line. Gastrointest Endosc 2006;63:250-6.\u003c/li\u003e\n\u003cli\u003eAl-Sohaily S, Leong RW. The yield of ileoscopy at colonoscopy. J Gastroenterol Hepatol 2008;23:4-5.\u003c/li\u003e\n\u003cli\u003eLeiman DA, Jawitz NG, Lin L, et al. Terminal ileum intubation is not associated with colonoscopy quality measures. J Gastroenterol Hepatol 2020;35:1503-1508.\u003c/li\u003e\n\u003cli\u003eGeboes K, Ectors N, D\u0026apos;Haens G, et al. Is ileoscopy with biopsy worthwhile in patients presenting with symptoms of inflammatory bowel disease? Am J Gastroenterol 1998;93:201-6.\u003c/li\u003e\n\u003cli\u003eMorini S, Lorenzetti R, Stella F, et al. Retrograde ileoscopy in chronic nonbloody diarrhea: a prospective, case-control study. Am J Gastroenterol 2003;98:1512-5.\u003c/li\u003e\n\u003cli\u003eZwas FR, Bonheim NA, Berken CA, et al. Diagnostic yield of routine ileoscopy. Am J Gastroenterol 1995;90:1441-3.\u003c/li\u003e\n\u003cli\u003eCherian S, Singh P. Is routine ileoscopy useful? An observational study of procedure times, diagnostic yield, and learning curve. Am J Gastroenterol 2004;99:2324-9.\u003c/li\u003e\n\u003cli\u003eAlkhatib AA, Kumar S. Clinical Yield of Ileal Intubation During Screening Colonoscopy. Cureus 2022;14:e20870.\u003c/li\u003e\n\u003cli\u003eKoureta E, Karatzas P, Tampaki M, et al. Isolated nonspecific terminal ileitis: prevalence, clinical evolution and correlation with metachronous diagnosis of Crohn\u0026apos;s disease: a retrospective study and review of the literature. Ann Gastroenterol 2024;37:199-205.\u003c/li\u003e\n\u003cli\u003eCourville EL, Siegel CA, Vay T, et al. Isolated asymptomatic ileitis does not progress to overt Crohn disease on long-term follow-up despite features of chronicity in ileal biopsies. Am J Surg Pathol 2009;33:1341-7.\u003c/li\u003e\n\u003cli\u003eWang W, Chen K, Xu Y, et al. Routine ileal intubation in colonoscopy does not increase the polyp detection rate: a retrospective study. Z Gastroenterol 2020;58:955-959.\u003c/li\u003e\n\u003cli\u003eBuerger M, Kasper P, Allo G, et al. Ileal intubation is not associated with higher detection rate of right-sided conventional adenomas and serrated polyps compared to cecal intubation after adjustment for overall adenoma detection rate. BMC Gastroenterol 2019;19:190.\u003c/li\u003e\n\u003cli\u003eKlare P, Phlipsen H, Haller B, et al. Longer observation time increases adenoma detection in the proximal colon - a prospective study. Endosc Int Open 2017;5:E1289-e1298.\u003c/li\u003e\n\u003cli\u003ePowell N, Knight H, Dunn J, et al. Images of the terminal ileum are more convincing than cecal images for verifying the extent of colonoscopy. Endoscopy 2011;43:196-201.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003e\u003cstrong\u003eTable1: \u0026nbsp;Abnormal endoscopic findings of ileal mucosa in unselected subjects\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.535353535353536%\" valign=\"top\"\u003e\n \u003cp\u003eEndoscopic findings\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.464646464646464%\" valign=\"top\"\u003e\n \u003cp\u003eN (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.535353535353536%\" valign=\"top\"\u003e\n \u003cp\u003eErosion/ulcer\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.464646464646464%\" valign=\"top\"\u003e\n \u003cp\u003e115 (76.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.535353535353536%\" valign=\"top\"\u003e\n \u003cp\u003eHyperemic/edematous mucosa\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.464646464646464%\" valign=\"top\"\u003e\n \u003cp\u003e18 (12.0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.535353535353536%\" valign=\"top\"\u003e\n \u003cp\u003ePolypoid or protruding lesion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.464646464646464%\" valign=\"top\"\u003e\n \u003cp\u003e13 (8.7%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.535353535353536%\" valign=\"top\"\u003e\n \u003cp\u003eStenosis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.464646464646464%\" valign=\"top\"\u003e\n \u003cp\u003e1 (0.6%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.535353535353536%\" valign=\"top\"\u003e\n \u003cp\u003eother\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.464646464646464%\" valign=\"top\"\u003e\n \u003cp\u003e3 (2.0%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"53.535353535353536%\" valign=\"top\"\u003e\n \u003cp\u003eTotal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"46.464646464646464%\" valign=\"top\"\u003e\n \u003cp\u003e150\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable2: \u0026nbsp; Pathologic findings of ileal mucosa in unselected subjects\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"59.5959595959596%\" valign=\"top\"\u003e\n \u003cp\u003ePathologic findings\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"40.4040404040404%\" valign=\"top\"\u003e\n \u003cp\u003eN\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"59.5959595959596%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eChronic/acute ileitis\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"40.4040404040404%\" valign=\"top\"\u003e\n \u003cp\u003e124\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"59.5959595959596%\" valign=\"top\"\u003e\n \u003cp\u003eNormal mucosa\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"40.4040404040404%\" valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"59.5959595959596%\" valign=\"top\"\u003e\n \u003cp\u003eTuberculosis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"40.4040404040404%\" valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"59.5959595959596%\" valign=\"top\"\u003e\n \u003cp\u003eInflammatory bowel disease\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"40.4040404040404%\" valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"59.5959595959596%\" valign=\"top\"\u003e\n \u003cp\u003eBehcet\u0026rsquo;s disease\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"40.4040404040404%\" valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"59.5959595959596%\" valign=\"top\"\u003e\n \u003cp\u003eUlcer\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"40.4040404040404%\" valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"59.5959595959596%\" valign=\"top\"\u003e\n \u003cp\u003eLymphoma\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"40.4040404040404%\" valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"59.5959595959596%\" valign=\"top\"\u003e\n \u003cp\u003eNo biopsy or Other lesion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"40.4040404040404%\" valign=\"top\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3:\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eEndoscopic and pathologic findings of ileal mucosa in asymptomatic subjects\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003eEndoscopic findings\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003eN\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003ePathologic findings\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003eN\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003eErosion/ulcer\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eNonspecific ileitis\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003eHyperemic/edematous mucosa\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003ePolypoid hyperplasia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003ePolypoid or protruding lesion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"25%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 4: Baseline characteristics and clinical outcome of patients before and after matching\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd width=\"19.387755102040817%\" rowspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"30.612244897959183%\" colspan=\"3\" valign=\"top\"\u003e\n \u003cp\u003eBefore matching\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"10.204081632653061%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"30.612244897959183%\" colspan=\"3\" valign=\"top\"\u003e\n \u003cp\u003eAfter matching\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"9.183673469387756%\" valign=\"top\"\u003e\n \u003cp\u003e\u003cem\u003eP\u0026nbsp;\u003c/em\u003evalue\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"18.181818181818183%\" valign=\"top\"\u003e\n \u003cp\u003eTII\u003c/p\u003e\n \u003cp\u003e(n=7599)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.48051948051948%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003eNo TII\u003c/p\u003e\n \u003cp\u003e(n=5773)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"12.987012987012987%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"18.181818181818183%\" valign=\"top\"\u003e\n \u003cp\u003eTII\u003c/p\u003e\n \u003cp\u003e(n=5552)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"19.48051948051948%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003eNo TII\u003c/p\u003e\n \u003cp\u003e(n=5552)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.688311688311689%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.736842105263158%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.68421052631579%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.578947368421053%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.736842105263158%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.68421052631579%\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.578947368421053%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20%\" valign=\"top\"\u003e\n \u003cp\u003eMedian Age, y (interquartile range)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.736842105263158%\" valign=\"top\"\u003e\n \u003cp\u003e53 (41, 61)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.68421052631579%\" valign=\"top\"\u003e\n \u003cp\u003e57 (48, 66)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.578947368421053%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.736842105263158%\" valign=\"top\"\u003e\n \u003cp\u003e55 (46, 64)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.68421052631579%\" valign=\"top\"\u003e\n \u003cp\u003e56 (47, 65)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.578947368421053%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e0.055\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20%\" valign=\"top\"\u003e\n \u003cp\u003eSex (male, n%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.736842105263158%\" valign=\"top\"\u003e\n \u003cp\u003e47.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.68421052631579%\" valign=\"top\"\u003e\n \u003cp\u003e49.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.578947368421053%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e0.019\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.736842105263158%\" valign=\"top\"\u003e\n \u003cp\u003e47.4%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.68421052631579%\" valign=\"top\"\u003e\n \u003cp\u003e49.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.578947368421053%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e0.095\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20%\" valign=\"top\"\u003e\n \u003cp\u003eInpatient (n%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.736842105263158%\" valign=\"top\"\u003e\n \u003cp\u003e34.1%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.68421052631579%\" valign=\"top\"\u003e\n \u003cp\u003e41.1%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.578947368421053%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.736842105263158%\" valign=\"top\"\u003e\n \u003cp\u003e38.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.68421052631579%\" valign=\"top\"\u003e\n \u003cp\u003e39.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.578947368421053%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e0.371\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20%\" valign=\"top\"\u003e\n \u003cp\u003eBody mass index, kg/m\u003csup\u003e2\u003c/sup\u003e (interquartile range)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.736842105263158%\" valign=\"top\"\u003e\n \u003cp\u003e23.05 (20.96, 25.33)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.68421052631579%\" valign=\"top\"\u003e\n \u003cp\u003e23.44 (21.22, 25.71)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.578947368421053%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.736842105263158%\" valign=\"top\"\u003e\n \u003cp\u003e22.89 (20.63, 25.06)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.68421052631579%\" valign=\"top\"\u003e\n \u003cp\u003e23.02 (20.57, 25.16)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.578947368421053%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e0.298\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20%\" valign=\"top\"\u003e\n \u003cp\u003eAdequate bowel preparation (n%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.736842105263158%\" valign=\"top\"\u003e\n \u003cp\u003e91.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.68421052631579%\" valign=\"top\"\u003e\n \u003cp\u003e87.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.578947368421053%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.736842105263158%\" valign=\"top\"\u003e\n \u003cp\u003e89.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.68421052631579%\" valign=\"top\"\u003e\n \u003cp\u003e88.9%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.578947368421053%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e0.258\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20%\" valign=\"top\"\u003e\n \u003cp\u003ePolyp detection rate (n%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.736842105263158%\" valign=\"top\"\u003e\n \u003cp\u003e47.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.68421052631579%\" valign=\"top\"\u003e\n \u003cp\u003e52.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.578947368421053%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.736842105263158%\" valign=\"top\"\u003e\n \u003cp\u003e50.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.68421052631579%\" valign=\"top\"\u003e\n \u003cp\u003e51.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.578947368421053%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e0.506\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20%\" valign=\"top\"\u003e\n \u003cp\u003eAdenoma detection rate (n%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.736842105263158%\" valign=\"top\"\u003e\n \u003cp\u003e27.4%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.68421052631579%\" valign=\"top\"\u003e\n \u003cp\u003e31.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.578947368421053%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.736842105263158%\" valign=\"top\"\u003e\n \u003cp\u003e30.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.68421052631579%\" valign=\"top\"\u003e\n \u003cp\u003e31.3%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.578947368421053%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e0.156\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20%\" valign=\"top\"\u003e\n \u003cp\u003eSessile serrated lesion detection rate (n%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.736842105263158%\" valign=\"top\"\u003e\n \u003cp\u003e1.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.68421052631579%\" valign=\"top\"\u003e\n \u003cp\u003e1.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.578947368421053%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e0.846\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.736842105263158%\" valign=\"top\"\u003e\n \u003cp\u003e1.8%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.68421052631579%\" valign=\"top\"\u003e\n \u003cp\u003e1.7%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.578947368421053%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e0.613\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd width=\"20%\" valign=\"top\"\u003e\n \u003cp\u003eRight-sided lesion detection rate (n%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.736842105263158%\" valign=\"top\"\u003e\n \u003cp\u003e14.4%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.68421052631579%\" valign=\"top\"\u003e\n \u003cp\u003e17.0%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.578947368421053%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e0.000\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"14.736842105263158%\" valign=\"top\"\u003e\n \u003cp\u003e16.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"13.68421052631579%\" valign=\"top\"\u003e\n \u003cp\u003e16.5%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd width=\"11.578947368421053%\" colspan=\"2\" valign=\"top\"\u003e\n \u003cp\u003e1.000\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\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":"bmc-gastroenterology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmge","sideBox":"Learn more about [BMC Gastroenterology](http://bmcgastroenterol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bmge/default.aspx","title":"BMC Gastroenterology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"terminal ileal intubation, cecal intubation, colonoscopy, diagnostic value, lesion detection rate","lastPublishedDoi":"10.21203/rs.3.rs-4875836/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4875836/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eTerminal ileal intubation (TII) demonstrates a complete colonoscopy, but whether it should be performed in routine colonoscopies remains uncertain. We aimed to explore the diagnostic yield of TII in routine colonoscopy and investigate the association of TII and the detection of lesion.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eWe conducted a retrospective study included patients who underwent colonoscopy with cecal intubation at our endoscopic center between November 1 2022 and July 31 2023. Macroscopic and histologic findings of terminal ileum were recorded. We used propensity score matching to adjust for differences between groups and further analyzed the difference of polyp detection rate (PDR), adenoma detection rate (ADR), sessile serrated lesion detection rate (SSDR) and right-sided lesion detection rate between patients underwent TII or not.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThere were 13372 patients with cecal intubation colonoscopy, including 7599 (56.8%) with TII and 5773 (43.2%) without TII. Abnormal endoscopic findings were observed in 150 of 7599 unselected individuals and only 7 of these cases were regarded as pathologically significant. Likewise, abnormal endoscopic findings were found in 20 of 1494 asymptomatic individuals with 19 nonspecific ileitis determined by histopathology. After PSM, there were no significant differences in PDR (51.5% vs 50.8%, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.506), ADR (31.3% vs 30.0%, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.156), SSDR (1.7% vs 1.8%, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.613) and right-sided lesion detection rate (16.5% vs 16.5%, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;1.000) between the two groups.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eTII was not proposed in routine colonoscopy, owing to the limited diagnostic value and lack of superiority on lesion detection.\u003c/p\u003e","manuscriptTitle":"Terminal ileal intubation is not recommended in routine colonoscopy: data from a large-scale retrospective study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-10-02 16:43:11","doi":"10.21203/rs.3.rs-4875836/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-08-09T09:32:54+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-08-09T07:14:53+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-08-09T07:14:20+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Gastroenterology","date":"2024-08-07T15:27:37+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-gastroenterology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"bmge","sideBox":"Learn more about [BMC Gastroenterology](http://bmcgastroenterol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/bmge/default.aspx","title":"BMC Gastroenterology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"af153ddf-ba49-4112-914e-e563524b72bd","owner":[],"postedDate":"October 2nd, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-12-02T16:02:14+00:00","versionOfRecord":{"articleIdentity":"rs-4875836","link":"https://doi.org/10.1186/s12876-024-03521-3","journal":{"identity":"bmc-gastroenterology","isVorOnly":false,"title":"BMC Gastroenterology"},"publishedOn":"2024-11-26 15:57:35","publishedOnDateReadable":"November 26th, 2024"},"versionCreatedAt":"2024-10-02 16:43:11","video":"","vorDoi":"10.1186/s12876-024-03521-3","vorDoiUrl":"https://doi.org/10.1186/s12876-024-03521-3","workflowStages":[]},"version":"v1","identity":"rs-4875836","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4875836","identity":"rs-4875836","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}