Comparison of Tc-99m scintigraphic method and radiological method for colon transmit assessment in patients with functional constipation

Comparison of Tc-99m scintigraphic method and radiological method for colon transmit assessment in patients with functional constipation | 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 Comparison of Tc-99m scintigraphic method and radiological method for colon transmit assessment in patients with functional constipation Yuan Tian, Yan Li, Ting Yi, Qiyue Wang, Xuan Jiang, Zuo-xiang He This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6449841/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 10 Oct, 2025 Read the published version in BMC Gastroenterology → Version 1 posted 14 You are reading this latest preprint version Abstract Background The methods for assessing colon transport in patients with functional constipation include the radiological method and Tc-99m scintigraphic method. This study aims to validate the practicality and accuracy of the Tc-99m scintigraphic method in evaluating colon transit, while also exploring the significance of the geometric center (GC). Methods Our study is a single-center, retrospective analysis. We examined the medical records of 47 patients, ranging in age from 18–81 years, who underwent colonic transit by the Tc-99m scintigraphic method and the radiological method for investigation of chronic constipation. Geometric center (GC) and transmit index (TI) were calculated respectively in these two methods. The patients were divided into four types of constipation: normal transit constipation (NTC), slow transit constipation (STC), defecatory disorders (DD) and STC combined with DD. Results The results of the Tc-99m scintigraphic method and radiological method were consistent in the diagnosis of slow colon transmission (Kappa value = 0.718, P<0.001). TI and 48-hour GC were positively correlated (r = 0.657, p = 0.001). Patients with DD exhibited higher 24-hour GC and 48-hour GC values compared to those with STC. Conclusion Tc-99m scintigraphic method can be used to evaluate colon transport in patients with constipation, and GC values may be used to distinguish the types of constipation. Constipation Tc-99m scintigraphic method radiological method Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Background Chronic constipation, a widespread yet frequently underestimated gastrointestinal disorder, affects a considerable proportion of the global population, with prevalence estimates ranging from 10–15% worldwide 1 . This condition significantly impacts patients' quality of life and burdens healthcare systems. The majority of constipation cases in the population are attributed to functional constipation (FC), which lacks an organic cause and falls under the category of functional gastrointestinal disease. After the clinical assessment, constipated patients may be tentatively classified into following categories: (1) normal transit constipation (NTC), (2) slow transit constipation (STC), (3) defecatory disorders (DD);(4) STC and DD. These subtypes can overlap with each other and with other functional gastrointestinal disorders 2 , 3 . The intricate mechanisms underlying FC remain largely unknown but are increasingly recognized as a complex interplay between colonic motility dysfunction, altered gut microbiome, visceral hypersensitivity, psychological factors, and dietary habits. Among these factors, impaired colonic transit is a pivotal aspect, particularly in STC, where delayed stool movement through the colon leads to water absorption, stool hardening, and subsequent evacuation difficulties 4 – 6 . Therefore, understanding the dynamics of colonic transmission is crucial for the effective diagnosis and management of FC. Current measurement methods of colonic transit primarily include the radiopaque marker test, wireless power capsule, and colon scintigraphy 7 . The radiopaque marker test represents the most economical and simplest method for assessing colonic transit and is widely used in China. However, patients are exposed to radiation, and the radiopaque markers differ from normal food, potentially affecting the assessment's accuracy. The wireless power capsule is devoid of radiation but requires expensive technical equipment, limiting its widespread use. Colon scintigraphy involves mixing a radionuclide with food and allowing it to enter the intestine, thereby best reflecting the physiological state and outlining the colon 8 . In China, only Tc-99m is available, which is typically used for assessing gastric and small intestinal transit due to its short half-life. However, in clinical practice, we observed that slow colonic transit leads to radionuclide accumulation, which partially mitigates nuclide attenuation. Consequently, the colon outline of most FC patients can still be visualized at 48 hours, and the residual radioactivity can be quantitatively calculated. Therefore, we hypothesize that scintigraphy using Tc-99m may have a certain value in assessing colonic transit in FC patients. The study aims to explore the utility of the Tc-99m scintigraphic method in assessing colonic transit and provide better and more diverse objective examination methods for the clinical evaluation of FC. Method Subjects We retrospectively included patients who visited the constipation clinic of our Hospital from January 2018 to February 2024 and met the following inclusion criteria. Inclusion criteria: 1. Aged ≥ 18 years; 2. Meet the Rome IV diagnostic criteria for functional constipation; 3. Complete Tc-99m scintigraphic method and radiopaque marker test; Exclusion criteria: 1. Have clear anatomical abnormalities or skeletal deformities or congenital intestinal diseases; 2. Constipation caused by drugs or organic causes; 3. Severe organ dysfunction or disease with a life expectancy of less than 3 months. The study was approved by the Ethics Committee. Radiopaque marker test We implemented the radiopaque marker test based on the “Hinton technique” 9 . The patients consumed a capsule with 24 radiopaque markers inside on the first day. A plain abdominal radiograph was obtained respectively on days 3 and 4. Patients maintained their regular diet and social routines but refrained from using laxatives, enemas, or bulking agents throughout the duration. Calculate the residual rate as residual marker number / 24 × 100%, a rate of residual >20% on day 4 is considered to be a slow colonic transit. A line was drawn from the thoracic spinous process to the T5 spinous process, and then a tangent line was drawn from the T5 spinous process to the right pelvic outlet and left iliac crest, serving as landmarks delineated the areas of the right, left, and rectosigmoid colon(Figure 1 ) 10 . The colon transit index (TI) was determined by dividing the count of RS marker remnants by the total count of marker remnants in the entire colon. The closer the TI value is to 0, the more likely it is STC; the closer the TI value is to 1, the more likely it is DD. Tc-99m scintigraphic method The solid meal includes 5mCi Tc-99m-DTPA labeled egg white (120g) and 2 slices of white bread (120 kcal) 8 . Images were acquired in the upright posture using a gamma scintillation camera (GE Discovery 670). Evaluation of absorption was based on the calculated geometric mean values derived from front and back scans. The images were gathered at 2, 4, 6, 24, 48, and 72 hours (Fig. 2 ). Radionuclide decay was adjusted, and the colon was marked by combining sequential scans. For each subject, regions of interest (ROI) were determined and drawn in the following manner: ROI 1, caecum and ascending colon including the hepatic flexure; ROI 2, transverse colon including the splenic flexure; ROI 3, descending colon including sigmoid colon; ROI 4, sigmoid colon and rectum; ROI 5, stool (Fig. 3 ). The geometric center (GC) is determined by summing the weighted fractions, which are represented by the counts in each region multiplied by the region number and then divided by the total counts. We calculated GC in 24h and 48h respectively. $$\:GC=\sum\:_{1}^{n}fraction\:of\:activity\:in\:{ROI}_{n}\:\times\:n$$ Statistical methods Non-parametric methods were applied. Differences among groups were assessed using the Kruskal-Wallis test. The connection between the GC and TI was assessed using Spearman's rank correlation coefficient. Kappa consistency test was used to compare the radiological and the scintigraphic method with respect to prolonged or normal transit time. A P-value below 0.05 was considered as significant. SPSS software was used for the calculations. Results 1. Patient characteristics From 2018 to 2024, a total number of 52 constipated patients participated in both the radiopaque marker test and colonic transit scintigraphy. Following the removal of patients with megacolon (n = 1) and those with incomplete or suboptimal study data (n = 4), 47 patients (30 female and 17 male) were ultimately enrolled in the research, with an age range of 18 to 81 years and an average age of 49.6 ± 17.5 (mean ± SD) years. Based on the radiopaque marker test and anorectal manometry results, we divided constipation patients into four types: NTC, STC, DD, and STC combined with DD. Constipation type: STC 9 cases (18.8%), DD 17 cases (35.4%), STC + DD 18 cases (37.5%), NTC 3 cases (6.3%) 2. The agreement between the Tc-99m scintigraphic method and the radiopaque marker test The study assessed the agreement between the radionuclide method (using Tc-99m scintigraphy) and the radiopaque marker test in evaluating colonic transit. According to the radiopaque marker test, 33 patients were identified with slow colonic transit, while 14 patients had normal transit. Conversely, the radionuclide method categorized 29 patients as having slow colonic transit and 18 as normal (Table 1 ). Table 1 Comparison between the results of Radiopaque Marker Test and Tc-99m Scintigraphic Method Tc-99m Scintigraphic Method Radiopaque Marker Test(n) Total (n) Slow Transmit Normal transmit Slow Transmit 28 1 29 Normal transmit 5 13 18 Total(n) 33 14 47 A comparison of the results from both methods revealed that 41 patients had consistent findings between the radiopaque marker test and the radionuclide method. The Kappa (κ) coefficient of concordance was calculated to quantify the agreement between these two methods. The resulting Kappa value was 0.718, with a P-value less than 0.001. This statistical outcome indicates good agreement between the radiopaque marker test and the radionuclide method in assessing colonic transit. 3. Geometric center (GC) is positively correlated with colonic transport index (TI) For the scintigraphic method, the geometric center (GC) is calculated for quantifying colon transit. In patients with abnormal colon transport, the larger the GC, which means that the nuclide accumulates in the lower intestine, the more prone to excretion obstruction constipation. In the radiopaque marker test, the transmit index (TI) quantitatively evaluated colonic transmission. The closer TI is to 1, the more likely it is to defecatory disorders, and the closer TI is to 0, the more likely it is to slow transit constipation. We further investigated the correlation between geometric center (GC) and transmit index (TI). The 48h TI of patients with the slow transmission of the radiopaque marker test was summarized, as shown in Fig. 4 . 48hGC and 48hTI were positively correlated (r = 0.657, p = 0.001), indicating a moderate correlation (see Fig. 5 ). 4. Association of GC with constipation types The results indicate differences in GC (Table 2 ). Specifically, patients with defecatory disorders (DD) exhibited higher 24-hour GC and 48-hour GC values compared to those with slow transit constipation (STC), and these differences were statistically significant (Fig. 6 ). Furthermore, the 48-hour GC values of patients with DD were notably higher than those of patients with STC + DD. Conversely, no statistically significant difference was observed between patients with STC and those with STC + DD, potentially suggesting overlapping mechanisms between these two types. These findings hint at the necessity of conducting further research with a larger sample size, which might lead to the establishment of reference ranges for 48-hour GC values that could aid in differentiating constipation subtypes. Table 2 The GC of different constipation types STC STC + DD DD NTC M ± SD M ± SD M ± SD M ± SD 24hGC 1.57 ± 0.29 2.09 ± 0.74 2.76 ± 1.09 4.17 ± 0.73 48hGC 2.15 ± 0.54 2.61 ± 0.59 4.22 ± 0.89 4.34 ± 0.36 Discussion 1. The results of the Tc-99m scintigraphic method is in accordance with the result of classical radiological method The primary innovation of this study lies in its validation of the feasibility of using the Tc-99m scintigraphic method to assess colon transit in patients with functional constipation. This non-invasive imaging technique offers a novel perspective on evaluating gastrointestinal motility, particularly in constipation, where traditional diagnostic methods may have limitations. Our findings demonstrate a moderate correlation between the results obtained via the Tc-99m scintigraphic method and the classical radiological method, suggesting that the scintigraphic approach can serve as a viable alternative or complementary tool in the clinical assessment of colon transit. This correlation not only underscores the potential utility of Tc-99m scintigraphy in providing quantitative data on colon transit times but also highlights its potential to contribute to a more comprehensive understanding of the underlying pathophysiology of functional constipation. 2. Potential Utility of 48-hour GC in Differentiating Constipation Types Another intriguing aspect of our study is the exploration of the 48-hour GC as a potential marker for differentiating various types of constipation. While this study did not directly categorize or analyze specific constipation subtypes, the notion that GC might offer insights into constipation heterogeneity deserves further investigation. By measuring the geometric center, Tc-99m scintigraphy may help identify distinct patterns of colon transit that could correlate with different constipation phenotypes. Such distinctions could be crucial for tailoring therapeutic strategies and improving patient outcomes, as the management of constipation often requires a nuanced approach based on its underlying cause and presentation. 3. Limitations Despite these promising findings, our study is not without limitations. Firstly, it was conducted as a single-center study, which may limit the generalizability of our results to broader patient populations. The homogeneity of patient care and diagnostic practices within a single institution can introduce biases that might not be present in a multicenter trial. Additionally, the sample size was relatively small, potentially reducing the statistical power of our analyses and increasing the risk of type II errors (failing to reject a false null hypothesis). Moreover, the distribution of constipation patients within our sample was not evenly balanced, which could affect the robustness of our conclusions when applied to specific constipation subtypes. To address these limitations, future research should aim to conduct multicenter trials with larger and more diverse patient populations, ensuring a balanced representation of different constipation types and severities. This would strengthen the statistical validity of the findings and enhance their applicability to real-world clinical scenarios. Furthermore, incorporating additional diagnostic tools and patient-reported outcome measures could provide a more holistic view of colon transit and its impact on patient's quality of life, ultimately contributing to more personalized and effective treatment strategies for functional constipation. Abbreviations FC: Functional Constipation NTC: Normal Transit Constipation STC: Slow Transit Constipation DD: Defecatory Disorders ROI: Region of Interest GC: Geometric Center TI: Transmit Index Tc-99m: Technetium-99m Tc-99m-DTPA: Technetium-99m Diethylenetriaminepentaacetic Acid Declarations Ethics approval and consent to participate This retrospective study was conducted in accordance with the ethical principles of the Declaration of Helsinki. The study did not involve any additional interventions on patients and the analyzed data did not include patients' personal information. Therefore, the requirement for informed consent from participants was waived. The Ethics Committee of the Beijing Tsinghua Changgung Hospital has approved this waiver. The study strictly protected patients' rights and welfare, ensuring that all research activities complied with the ethical guidelines outlined in the Declaration of Helsinki. Consent for publication Not Applicable Availability of data and materials The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request. Competing Interests Not applicable. Funding No financial support was received for the preparation of the manuscript. Authors' contributions Yuan Tian: Data curation, Formal analysis, Writing - original draft, Writing - review & editing. Yan Li: Data curation, Formal analysis. Ting Yi: Data curation. Qiyue Wang: Data curation. Xuan Jiang: Conceptualization, Investigation, Supervision. Zuo-xiang He: Conceptualization, Supervision. Acknowledgements Not applicable References Aziz IWW, Palsson OS, Törnblom H, Simrén M. An approach to the diagnosis and management of Rome IV functional disorders of chronic constipation. Expert Review of Gastroenterology & Hepatology; 2020. pp. 39–46. Pannemans J, Masuy I, Tack J. Funct Constipation: Individualising Assess Treat Drugs. 2020;80:947–63. Bharucha AE, Wald A. Chronic Constipation. Mayo Clinic Proceedings. 2019;94:2340–2357. Bharucha AE, Lacy BE. Mechanisms, Evaluation, and Management of Chronic Constipation. Gastroenterology. 2020;158:1232–e12491233. Dimidi E, Christodoulides S, Scott SM, Whelan K. Mechanisms of Action of Probiotics and the Gastrointestinal Microbiota on Gut Motility and Constipation. Adv Nutr. 2017;8:484–94. Dimidi E, Mark Scott S, Whelan K. Probiotics and constipation: mechanisms of action, evidence for effectiveness and utilisation by patients and healthcare professionals. Proc Nutr Soc. 2020;79:147–57. Szarka LA, Camilleri M. Methods for the assessment of small-bowel and colonic transit. Semin Nucl Med. 2012;42:113–23. Maurer AH, Camilleri M, Donohoe K, et al. The SNMMI and EANM Practice Guideline for Small-Bowel and Colon Transit 1.0. J Nucl Med. 2013;54:2004–13. Hinton JM, Lennard-Jones JE, Young AC. A new method for studying gut transit times using radioopaque markers.Gut,1969,10(10):842–7. Kim ER, Rhee PL. How to interpret a functional or motility test - colon transit study. J Neurogastroenterol Motil. 2012;18(1):94–9. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 10 Oct, 2025 Read the published version in BMC Gastroenterology → Version 1 posted Editorial decision: Revision requested 29 Jul, 2025 Reviews received at journal 27 Jul, 2025 Reviews received at journal 22 Jul, 2025 Reviews received at journal 15 Jul, 2025 Reviewers agreed at journal 10 Jul, 2025 Reviewers agreed at journal 10 Jul, 2025 Reviewers agreed at journal 09 Jul, 2025 Reviews received at journal 28 Jun, 2025 Reviewers agreed at journal 26 Jun, 2025 Reviewers invited by journal 23 Jun, 2025 Editor assigned by journal 23 Jun, 2025 Editor invited by journal 23 Jun, 2025 Submission checks completed at journal 20 Jun, 2025 First submitted to journal 20 Jun, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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GC\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-6449841/v1/56a2879e42beaf43765cb4be.png"},{"id":85618847,"identity":"7db1c6d1-c707-453c-a311-89474d024ddc","added_by":"auto","created_at":"2025-06-29 14:53:06","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":110585,"visible":true,"origin":"","legend":"\u003cp\u003eThe 48h TI of patients with the slow transmission of the Radiopaque Marker Test\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-6449841/v1/86a4ae2ff2418b0446e33a2f.png"},{"id":85617315,"identity":"ab348143-6245-4b52-9663-994d4d3b9a05","added_by":"auto","created_at":"2025-06-29 14:45:06","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":78961,"visible":true,"origin":"","legend":"\u003cp\u003eThe correlation between geometric center (GC) and transmit\u003c/p\u003e","description":"","filename":"floatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-6449841/v1/1d96b3b271c211d7e5369ba2.png"},{"id":85617321,"identity":"08ac9d46-8930-4a95-b700-09b871079375","added_by":"auto","created_at":"2025-06-29 14:45:06","extension":"jpeg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":147291,"visible":true,"origin":"","legend":"\u003cp\u003eThe GC values among patients with different types of constipation\u003c/p\u003e","description":"","filename":"floatimage6.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-6449841/v1/ee1b03fce5c3f9309c76f68f.jpeg"},{"id":93419548,"identity":"5f664d36-0eef-46c3-bfd5-bb761fd1f3e1","added_by":"auto","created_at":"2025-10-13 16:03:55","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1523721,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6449841/v1/fcd2997c-9ea4-4d33-b161-576667c0a2f0.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Comparison of Tc-99m scintigraphic method and radiological method for colon transmit assessment in patients with functional constipation","fulltext":[{"header":"Background","content":"\u003cp\u003eChronic constipation, a widespread yet frequently underestimated gastrointestinal disorder, affects a considerable proportion of the global population, with prevalence estimates ranging from 10\u0026ndash;15% worldwide\u003csup\u003e1\u003c/sup\u003e. This condition significantly impacts patients' quality of life and burdens healthcare systems. The majority of constipation cases in the population are attributed to functional constipation (FC), which lacks an organic cause and falls under the category of functional gastrointestinal disease. After the clinical assessment, constipated patients may be tentatively classified into following categories: (1) normal transit constipation (NTC), (2) slow transit constipation (STC), (3) defecatory disorders (DD);(4) STC and DD. These subtypes can overlap with each other and with other functional gastrointestinal disorders\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eThe intricate mechanisms underlying FC remain largely unknown but are increasingly recognized as a complex interplay between colonic motility dysfunction, altered gut microbiome, visceral hypersensitivity, psychological factors, and dietary habits. Among these factors, impaired colonic transit is a pivotal aspect, particularly in STC, where delayed stool movement through the colon leads to water absorption, stool hardening, and subsequent evacuation difficulties\u003csup\u003e\u003cspan additionalcitationids=\"CR5\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e. Therefore, understanding the dynamics of colonic transmission is crucial for the effective diagnosis and management of FC.\u003c/p\u003e \u003cp\u003eCurrent measurement methods of colonic transit primarily include the radiopaque marker test, wireless power capsule, and colon scintigraphy \u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e. The radiopaque marker test represents the most economical and simplest method for assessing colonic transit and is widely used in China. However, patients are exposed to radiation, and the radiopaque markers differ from normal food, potentially affecting the assessment's accuracy. The wireless power capsule is devoid of radiation but requires expensive technical equipment, limiting its widespread use. Colon scintigraphy involves mixing a radionuclide with food and allowing it to enter the intestine, thereby best reflecting the physiological state and outlining the colon \u003csup\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eIn China, only Tc-99m is available, which is typically used for assessing gastric and small intestinal transit due to its short half-life. However, in clinical practice, we observed that slow colonic transit leads to radionuclide accumulation, which partially mitigates nuclide attenuation. Consequently, the colon outline of most FC patients can still be visualized at 48 hours, and the residual radioactivity can be quantitatively calculated. Therefore, we hypothesize that scintigraphy using Tc-99m may have a certain value in assessing colonic transit in FC patients.\u003c/p\u003e \u003cp\u003eThe study aims to explore the utility of the Tc-99m scintigraphic method in assessing colonic transit and provide better and more diverse objective examination methods for the clinical evaluation of FC.\u003c/p\u003e"},{"header":"Method","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\n \u003ch2\u003eSubjects\u003c/h2\u003e\n \u003cp\u003eWe retrospectively included patients who visited the constipation clinic of our Hospital from January 2018 to February 2024 and met the following inclusion criteria.\u003c/p\u003e\n \u003cp\u003eInclusion criteria:\u003c/p\u003e\u003cspan\u003e\n \u003cp\u003e1. Aged\u0026thinsp;\u0026ge;\u0026thinsp;18 years;\u003c/p\u003e\n \u003c/span\u003e \u003cspan\u003e\n \u003cp\u003e2. Meet the Rome IV diagnostic criteria for functional constipation;\u003c/p\u003e\n \u003c/span\u003e \u003cspan\u003e\n \u003cp\u003e3. Complete Tc-99m scintigraphic method and radiopaque marker test;\u003c/p\u003e\n \u003c/span\u003e\n \u003cp\u003eExclusion criteria:\u003c/p\u003e\u003cspan\u003e\n \u003cp\u003e1. Have clear anatomical abnormalities or skeletal deformities or congenital intestinal diseases;\u003c/p\u003e\n \u003c/span\u003e \u003cspan\u003e\n \u003cp\u003e2. Constipation caused by drugs or organic causes;\u003c/p\u003e\n \u003c/span\u003e \u003cspan\u003e\n \u003cp\u003e3. Severe organ dysfunction or disease with a life expectancy of less than 3 months.\u003c/p\u003e\n \u003c/span\u003e\n \u003cp\u003eThe study was approved by the Ethics Committee.\u003c/p\u003e\n\u003c/div\u003e\n\u003ch3\u003eRadiopaque marker test\u003c/h3\u003e\n\u003cp\u003eWe implemented the radiopaque marker test based on the \u0026ldquo;Hinton technique\u0026rdquo; \u003csup\u003e\u003cspan class=\"CitationRef\"\u003e9\u003c/span\u003e\u003c/sup\u003e. The patients consumed a capsule with 24 radiopaque markers inside on the first day. A plain abdominal radiograph was obtained respectively on days 3 and 4. Patients maintained their regular diet and social routines but refrained from using laxatives, enemas, or bulking agents throughout the duration. Calculate the residual rate as residual marker number / 24 \u0026times; 100%, a rate of residual \u0026gt;20% on day 4 is considered to be a slow colonic transit. A line was drawn from the thoracic spinous process to the T5 spinous process, and then a tangent line was drawn from the T5 spinous process to the right pelvic outlet and left iliac crest, serving as landmarks delineated the areas of the right, left, and rectosigmoid colon(Figure \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e)\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e10\u003c/span\u003e\u003c/sup\u003e. The colon transit index (TI) was determined by dividing the count of RS marker remnants by the total count of marker remnants in the entire colon. The closer the TI value is to 0, the more likely it is STC; the closer the TI value is to 1, the more likely it is DD.\u003c/p\u003e\n\u003ch3\u003eTc-99m scintigraphic method\u003c/h3\u003e\n\u003cp\u003eThe solid meal includes 5mCi Tc-99m-DTPA labeled egg white (120g) and 2 slices of white bread (120 kcal) \u003csup\u003e\u003cspan class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e. Images were acquired in the upright posture using a gamma scintillation camera (GE Discovery 670). Evaluation of absorption was based on the calculated geometric mean values derived from front and back scans. The images were gathered at 2, 4, 6, 24, 48, and 72 hours (Fig. \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e). Radionuclide decay was adjusted, and the colon was marked by combining sequential scans. For each subject, regions of interest (ROI) were determined and drawn in the following manner: ROI 1, caecum and ascending colon including the hepatic flexure; ROI 2, transverse colon including the splenic flexure; ROI 3, descending colon including sigmoid colon; ROI 4, sigmoid colon and rectum; ROI 5, stool (Fig. \u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e). The geometric center (GC) is determined by summing the weighted fractions, which are represented by the counts in each region multiplied by the region number and then divided by the total counts. We calculated GC in 24h and 48h respectively.\u003c/p\u003e\n\u003cdiv id=\"Equa\" class=\"Equation\"\u003e\n \u003cdiv class=\"mathdisplay\" id=\"FileID_Equa\" name=\"EquationSource\"\u003e$$\\:GC=\\sum\\:_{1}^{n}fraction\\:of\\:activity\\:in\\:{ROI}_{n}\\:\\times\\:n$$\u003c/div\u003e\n\u003c/div\u003e\n\u003ch3\u003eStatistical methods\u003c/h3\u003e\n\u003cp\u003eNon-parametric methods were applied. Differences among groups were assessed using the Kruskal-Wallis test. The connection between the GC and TI was assessed using Spearman\u0026apos;s rank correlation coefficient. Kappa consistency test was used to compare the radiological and the scintigraphic method with respect to prolonged or normal transit time. A P-value below 0.05 was considered as significant. SPSS software was used for the calculations.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cspan\u003e\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e1. Patient characteristics\u003c/p\u003e\n\u003cp\u003e\u003c/p\u003e\n\u003cp\u003eFrom 2018 to 2024, a total number of 52 constipated patients participated in both the radiopaque marker test and colonic transit scintigraphy. Following the removal of patients with megacolon (n\u0026thinsp;=\u0026thinsp;1) and those with incomplete or suboptimal study data (n\u0026thinsp;=\u0026thinsp;4), 47 patients (30 female and 17 male) were ultimately enrolled in the research, with an age range of 18 to 81 years and an average age of 49.6\u0026thinsp;\u0026plusmn;\u0026thinsp;17.5 (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD) years. Based on the radiopaque marker test and anorectal manometry results, we divided constipation patients into four types: NTC, STC, DD, and STC combined with DD. Constipation type: STC 9 cases (18.8%), DD 17 cases (35.4%), STC\u0026thinsp;+\u0026thinsp;DD 18 cases (37.5%), NTC 3 cases (6.3%)\u003c/p\u003e\n\u003cp\u003e\u003cspan\u003e\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e2. The agreement between the Tc-99m scintigraphic method and the radiopaque marker test\u003c/p\u003e\n\u003cp\u003e\u003c/p\u003e\n\u003cp\u003eThe study assessed the agreement between the radionuclide method (using Tc-99m scintigraphy) and the radiopaque marker test in evaluating colonic transit. According to the radiopaque marker test, 33 patients were identified with slow colonic transit, while 14 patients had normal transit. Conversely, the radionuclide method categorized 29 patients as having slow colonic transit and 18 as normal (Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eComparison between the results of Radiopaque Marker Test and Tc-99m Scintigraphic Method\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"4\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eTc-99m Scintigraphic Method\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eRadiopaque Marker Test(n)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eTotal (n)\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eSlow Transmit\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eNormal transmit\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSlow Transmit\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e29\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNormal transmit\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e18\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTotal(n)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e47\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eA comparison of the results from both methods revealed that 41 patients had consistent findings between the radiopaque marker test and the radionuclide method. The Kappa (\u0026kappa;) coefficient of concordance was calculated to quantify the agreement between these two methods. The resulting Kappa value was 0.718, with a P-value less than 0.001. This statistical outcome indicates good agreement between the radiopaque marker test and the radionuclide method in assessing colonic transit.\u003c/p\u003e\n\u003cp\u003e\u003cspan\u003e\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e3. Geometric center (GC) is positively correlated with colonic transport index (TI)\u003c/p\u003e\n\u003cp\u003e\u003c/p\u003e\n\u003cp\u003eFor the scintigraphic method, the geometric center (GC) is calculated for quantifying colon transit. In patients with abnormal colon transport, the larger the GC, which means that the nuclide accumulates in the lower intestine, the more prone to excretion obstruction constipation. In the radiopaque marker test, the transmit index (TI) quantitatively evaluated colonic transmission. The closer TI is to 1, the more likely it is to defecatory disorders, and the closer TI is to 0, the more likely it is to slow transit constipation.\u003c/p\u003e\n\u003cp\u003eWe further investigated the correlation between geometric center (GC) and transmit index (TI). The 48h TI of patients with the slow transmission of the radiopaque marker test was summarized, as shown in Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e. 48hGC and 48hTI were positively correlated (r\u0026thinsp;=\u0026thinsp;0.657, p\u0026thinsp;=\u0026thinsp;0.001), indicating a moderate correlation (see Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e\n\u003cp\u003e\u003cspan\u003e\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e4. Association of GC with constipation types\u003c/p\u003e\n\u003cp\u003e\u003c/p\u003e\n\u003cp\u003eThe results indicate differences in GC (Table \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e). Specifically, patients with defecatory disorders (DD) exhibited higher 24-hour GC and 48-hour GC values compared to those with slow transit constipation (STC), and these differences were statistically significant (Fig. \u003cspan class=\"InternalRef\"\u003e6\u003c/span\u003e). Furthermore, the 48-hour GC values of patients with DD were notably higher than those of patients with STC\u0026thinsp;+\u0026thinsp;DD. Conversely, no statistically significant difference was observed between patients with STC and those with STC\u0026thinsp;+\u0026thinsp;DD, potentially suggesting overlapping mechanisms between these two types. These findings hint at the necessity of conducting further research with a larger sample size, which might lead to the establishment of reference ranges for 48-hour GC values that could aid in differentiating constipation subtypes.\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003ctable id=\"Tab2\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eThe GC of different constipation types\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003ccolgroup cols=\"5\"\u003e\u003c/colgroup\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSTC\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSTC\u0026thinsp;+\u0026thinsp;DD\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eDD\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eNTC\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM\u0026thinsp;\u0026plusmn;\u0026thinsp;SD\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e24hGC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.57\u0026thinsp;\u0026plusmn;\u0026thinsp;0.29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.09\u0026thinsp;\u0026plusmn;\u0026thinsp;0.74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.76\u0026thinsp;\u0026plusmn;\u0026thinsp;1.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.17\u0026thinsp;\u0026plusmn;\u0026thinsp;0.73\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e48hGC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.15\u0026thinsp;\u0026plusmn;\u0026thinsp;0.54\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.61\u0026thinsp;\u0026plusmn;\u0026thinsp;0.59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.22\u0026thinsp;\u0026plusmn;\u0026thinsp;0.89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4.34\u0026thinsp;\u0026plusmn;\u0026thinsp;0.36\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003e1. The results of the Tc-99m scintigraphic method is in accordance with the result of classical radiological method\u003c/p\u003e \u003cp\u003eThe primary innovation of this study lies in its validation of the feasibility of using the Tc-99m scintigraphic method to assess colon transit in patients with functional constipation. This non-invasive imaging technique offers a novel perspective on evaluating gastrointestinal motility, particularly in constipation, where traditional diagnostic methods may have limitations. Our findings demonstrate a moderate correlation between the results obtained via the Tc-99m scintigraphic method and the classical radiological method, suggesting that the scintigraphic approach can serve as a viable alternative or complementary tool in the clinical assessment of colon transit. This correlation not only underscores the potential utility of Tc-99m scintigraphy in providing quantitative data on colon transit times but also highlights its potential to contribute to a more comprehensive understanding of the underlying pathophysiology of functional constipation.\u003c/p\u003e \u003cp\u003e2. Potential Utility of 48-hour GC in Differentiating Constipation Types\u003c/p\u003e \u003cp\u003eAnother intriguing aspect of our study is the exploration of the 48-hour GC as a potential marker for differentiating various types of constipation. While this study did not directly categorize or analyze specific constipation subtypes, the notion that GC might offer insights into constipation heterogeneity deserves further investigation. By measuring the geometric center, Tc-99m scintigraphy may help identify distinct patterns of colon transit that could correlate with different constipation phenotypes. Such distinctions could be crucial for tailoring therapeutic strategies and improving patient outcomes, as the management of constipation often requires a nuanced approach based on its underlying cause and presentation.\u003c/p\u003e \u003cp\u003e3. Limitations\u003c/p\u003e \u003cp\u003eDespite these promising findings, our study is not without limitations. Firstly, it was conducted as a single-center study, which may limit the generalizability of our results to broader patient populations. The homogeneity of patient care and diagnostic practices within a single institution can introduce biases that might not be present in a multicenter trial. Additionally, the sample size was relatively small, potentially reducing the statistical power of our analyses and increasing the risk of type II errors (failing to reject a false null hypothesis). Moreover, the distribution of constipation patients within our sample was not evenly balanced, which could affect the robustness of our conclusions when applied to specific constipation subtypes.\u003c/p\u003e \u003cp\u003eTo address these limitations, future research should aim to conduct multicenter trials with larger and more diverse patient populations, ensuring a balanced representation of different constipation types and severities. This would strengthen the statistical validity of the findings and enhance their applicability to real-world clinical scenarios. Furthermore, incorporating additional diagnostic tools and patient-reported outcome measures could provide a more holistic view of colon transit and its impact on patient's quality of life, ultimately contributing to more personalized and effective treatment strategies for functional constipation.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eFC: Functional Constipation\u003c/p\u003e\n\u003cp\u003eNTC: Normal Transit Constipation\u003c/p\u003e\n\u003cp\u003eSTC: Slow Transit Constipation\u003c/p\u003e\n\u003cp\u003eDD: Defecatory Disorders\u003c/p\u003e\n\u003cp\u003eROI: Region of Interest\u003c/p\u003e\n\u003cp\u003eGC: Geometric Center\u003c/p\u003e\n\u003cp\u003eTI: Transmit Index\u003c/p\u003e\n\u003cp\u003eTc-99m: Technetium-99m\u003c/p\u003e\n\u003cp\u003eTc-99m-DTPA: Technetium-99m Diethylenetriaminepentaacetic Acid\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eEthics approval and consent to participate\u003c/p\u003e\n\u003cp\u003eThis retrospective study was conducted in accordance with the ethical principles of the Declaration of Helsinki. \u0026nbsp;The study did not involve any additional interventions on patients and the analyzed data did not include patients\u0026apos; personal information. \u0026nbsp; Therefore, the requirement for informed consent from participants was waived. The Ethics Committee of the Beijing Tsinghua Changgung Hospital has approved this waiver. The study strictly protected patients\u0026apos; rights and welfare, ensuring that all research activities complied with the ethical guidelines outlined in the Declaration of Helsinki.\u003c/p\u003e\n\u003cp\u003eConsent for publication\u003c/p\u003e\n\u003cp\u003eNot Applicable\u003c/p\u003e\n\u003cp\u003eAvailability of data and materials\u003c/p\u003e\n\u003cp\u003eThe datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003eCompeting Interests\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003eFunding\u003c/p\u003e\n\u003cp\u003eNo financial support was received for the preparation of the manuscript.\u003c/p\u003e\n\u003cp\u003eAuthors\u0026apos; contributions\u003c/p\u003e\n\u003cp\u003eYuan Tian: Data curation, Formal analysis, Writing - original draft, Writing - review \u0026amp; editing.\u003c/p\u003e\n\u003cp\u003eYan Li: Data curation, Formal analysis.\u003c/p\u003e\n\u003cp\u003eTing Yi: Data curation.\u003c/p\u003e\n\u003cp\u003eQiyue Wang: Data curation.\u003c/p\u003e\n\u003cp\u003eXuan Jiang: Conceptualization, Investigation, Supervision.\u003c/p\u003e\n\u003cp\u003eZuo-xiang He: Conceptualization, Supervision.\u003c/p\u003e\n\u003cp\u003eAcknowledgements\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eAziz IWW, Palsson OS, T\u0026ouml;rnblom H, Simr\u0026eacute;n M. An approach to the diagnosis and management of Rome IV functional disorders of chronic constipation. Expert Review of Gastroenterology \u0026amp; Hepatology; 2020. pp. 39\u0026ndash;46.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePannemans J, Masuy I, Tack J. Funct Constipation: Individualising Assess Treat Drugs. 2020;80:947\u0026ndash;63.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBharucha AE, Wald A. Chronic Constipation. Mayo Clinic Proceedings. 2019;94:2340\u0026ndash;2357.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBharucha AE, Lacy BE. Mechanisms, Evaluation, and Management of Chronic Constipation. Gastroenterology. 2020;158:1232\u0026ndash;e12491233.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDimidi E, Christodoulides S, Scott SM, Whelan K. Mechanisms of Action of Probiotics and the Gastrointestinal Microbiota on Gut Motility and Constipation. Adv Nutr. 2017;8:484\u0026ndash;94.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDimidi E, Mark Scott S, Whelan K. Probiotics and constipation: mechanisms of action, evidence for effectiveness and utilisation by patients and healthcare professionals. Proc Nutr Soc. 2020;79:147\u0026ndash;57.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSzarka LA, Camilleri M. Methods for the assessment of small-bowel and colonic transit. Semin Nucl Med. 2012;42:113\u0026ndash;23.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMaurer AH, Camilleri M, Donohoe K, et al. The SNMMI and EANM Practice Guideline for Small-Bowel and Colon Transit 1.0. J Nucl Med. 2013;54:2004\u0026ndash;13.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHinton JM, Lennard-Jones JE, Young AC. A new method for studying gut transit times using radioopaque markers.Gut,1969,10(10):842\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKim ER, Rhee PL. How to interpret a functional or motility test - colon transit study. J Neurogastroenterol Motil. 2012;18(1):94\u0026ndash;9.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"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":"Constipation, Tc-99m scintigraphic method, radiological method","lastPublishedDoi":"10.21203/rs.3.rs-6449841/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6449841/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e \u003cp\u003eThe methods for assessing colon transport in patients with functional constipation include the radiological method and Tc-99m scintigraphic method. This study aims to validate the practicality and accuracy of the Tc-99m scintigraphic method in evaluating colon transit, while also exploring the significance of the geometric center (GC).\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eOur study is a single-center, retrospective analysis. We examined the medical records of 47 patients, ranging in age from 18\u0026ndash;81 years, who underwent colonic transit by the Tc-99m scintigraphic method and the radiological method for investigation of chronic constipation. Geometric center (GC) and transmit index (TI) were calculated respectively in these two methods. The patients were divided into four types of constipation: normal transit constipation (NTC), slow transit constipation (STC), defecatory disorders (DD) and STC combined with DD.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e \u003cp\u003eThe results of the Tc-99m scintigraphic method and radiological method were consistent in the diagnosis of slow colon transmission (Kappa value\u0026thinsp;=\u0026thinsp;0.718, P\u0026lt;0.001). TI and 48-hour GC were positively correlated (r\u0026thinsp;=\u0026thinsp;0.657, p\u0026thinsp;=\u0026thinsp;0.001). Patients with DD exhibited higher 24-hour GC and 48-hour GC values compared to those with STC.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eTc-99m scintigraphic method can be used to evaluate colon transport in patients with constipation, and GC values may be used to distinguish the types of constipation.\u003c/p\u003e","manuscriptTitle":"Comparison of Tc-99m scintigraphic method and radiological method for colon transmit assessment in patients with functional constipation","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-29 14:45:01","doi":"10.21203/rs.3.rs-6449841/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-07-29T11:02:33+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-27T11:03:01+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-22T15:14:32+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-15T07:14:23+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"21360867641319371764323176293179555757","date":"2025-07-10T19:33:26+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"214576753539446997367724752984556500528","date":"2025-07-10T10:58:31+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"36669911903436320949683600730800273431","date":"2025-07-09T09:44:09+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-06-28T17:44:36+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"263837223081464528618984282111496850962","date":"2025-06-26T14:35:08+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-06-24T00:27:37+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-06-24T00:25:42+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-06-23T16:32:20+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-06-20T13:34:04+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Gastroenterology","date":"2025-06-20T13:31:32+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":"3f094589-d2b9-4023-905c-79f0b400b1e6","owner":[],"postedDate":"June 29th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-10-13T15:59:21+00:00","versionOfRecord":{"articleIdentity":"rs-6449841","link":"https://doi.org/10.1186/s12876-025-04299-8","journal":{"identity":"bmc-gastroenterology","isVorOnly":false,"title":"BMC Gastroenterology"},"publishedOn":"2025-10-10 15:57:05","publishedOnDateReadable":"October 10th, 2025"},"versionCreatedAt":"2025-06-29 14:45:01","video":"","vorDoi":"10.1186/s12876-025-04299-8","vorDoiUrl":"https://doi.org/10.1186/s12876-025-04299-8","workflowStages":[]},"version":"v1","identity":"rs-6449841","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6449841","identity":"rs-6449841","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}