Detecting Anemia in Pediatrics by unenhanced thoracic Computed Tomography Scan

Detecting Anemia in Pediatrics by unenhanced thoracic Computed Tomography Scan | 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 Detecting Anemia in Pediatrics by unenhanced thoracic Computed Tomography Scan Masoud Mahdavi Rashed, Ehsan Hassannejad, Navid Zavvar, Kimia Tarrah, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7508114/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background The present study aimed to evaluate the diagnostic accuracy of subjective and objective criteria for diagnosing anemia on an unenhanced thoracic CT scan in infants and children. Results A total of 281 subjects were included in the study. The prevalence of mild, moderate, and severe anemia in the participants was 34 (12.1%), 126 (44.8%), and 14 (5%) individuals, respectively. Additionally, 104 (37%) cases represented the aortic rim sign, and 79 (28.1%) represented the interventricular septum sign. The interventricular septum sign presented 35.05% of sensitivity and 83% specificity, while the aortic rim sign indicated 41.37% and 69.81% of sensitivity and specificity, respectively. Conclusion It is possible to detect anemia from an unenhanced chest CT scan. Both objective and subjective criteria show values of sensitivity and specificity; however, in some cases, it would not be reliable. Additionally, a chest CT scan would be more accurate in detecting severe anemia. Anemia Chest CT scan CT diagnosis Infant Children Figures Figure 1 1. Background Anemia is known as the reduced number of red blood cells in the human circulation, which can clinically be represented by the decreased serum hemoglobin (Hb) concentration in complete blood count analysis (1); in detail, the definition of anemia involves a decline in hemoglobin or hematocrit levels below the 2.5th percentile for age, race, and sex (2). According to the latest research, anemia is not only a common health problem worldwide but also a condition that can give rise to a diverse range of morbidities, thus posing a substantial global health concern (3). The global incidence of anemia affects roughly two million individuals, which constitutes almost a quarter of the worldwide population. (4). According to our current knowledge, children who have anemia may experience adverse effects on their cognitive and motor development, making them more vulnerable to infections. The enhanced susceptibility to infections, including life-threatening ones like malaria, can potentially amplify the risk of childhood mortality (5, 6). Furthermore, anemia may contribute to an elevated likelihood of hospitalization, unfavorable prognosis for both medical and surgical results, and heightened mortality across all causes (7). The computed tomography (CT) scan is a medical imaging technique that is commonly utilized for non-invasive visualization and diagnosis of various conditions affecting different body parts (8, 9, 10). It is not uncommon for CT scans to reveal incidental findings; while some of them could not be important to pay attention to, some others have a considerable impact on patients’ management and outcomes (11). Few previous reports have highlighted that anemia can be incidentally detected during unenhanced thoracic CT scans (12). This implies that anemia, a condition characterized by low red blood cell levels, can be detected through chest CT scans, even if the primary purpose of the scan is unrelated to evaluating anemia (13). In acute conditions, such as in trauma patients, there is often limited time to wait for peripheral blood test analysis. In these situations, obtaining a diagnosis through a CT scan, which is commonly performed, can be highly beneficial. It is imperative because non-contrast chest CT scans may reveal specific findings that can suggest the presence of anemia. Examples of these findings include a relatively dense interventricular septum (known as the septal sign), differences in CT attenuation between the interventricular septum and left ventricle cavity (IVS-LV), or a relatively hyper-attenuating aortic wall (the aortic ring sign) (14, 15). These findings are subjective and reader-dependent and subject to significant inter-observer variability. In addition, it is essential to note that certain conditions, like glycogen or iron storage diseases, can lead to findings that may falsely indicate anemia (16). On the other hand, objective analysis offers a more precise evaluation of anemia. A more accurate assessment of anemia can be made by measuring the attenuation value, which represents a reproducible physical density measurement and can be obtained from a standard CT examination. It is worth mentioning that there is no established cut-off in blood attenuation on non-contrast chest CT scans to suggest the definitive presence of anemia. To address it, the current study evaluated the diagnostic accuracy of subjective and objective criteria for diagnosing anemia on an unenhanced thoracic CT scan in infants and children. 2. Methods The present retrospective cross-sectional study was conducted on eligible patients admitted to Imam Reza and Ghaem Hospitals as academic hospitals of Mashhad University of Medical Sciences, Mashhad, Iran. The Ethics committee of Mashhad University of Medical Sciences, Mashhad, Iran approved this retrospective observational study. The review board at MUMS waived informed consent due to the observational nature of the research, under the waiver statement (ETHICAL CODE: IR.MUMS.MEDICAL.REC.1401.284). The sample size was calculated at a minimum of 240 cases due to Zohu et al.'s (14) study by considering the power as 80% and the confidence interval as 95%. 2.1. Patient selection Patients under 18 years old with documented non-contrast chest CT scan and complete blood count (CBC) evaluation within 24 hours of unenhanced thoracic CT scan who were admitted to … pediatrics' Hospitals, were included in the present study; however, documents with significant artifact in the chest CT scan and who received blood product transfusion were excluded. Clinical assessment, laboratory investigations, and unenhanced thoracic CT scans were reviewed for each patient. Anemia was defined based on the World Health Organization (WHO) definitions (17) (Table 1 ). Table 1 Hemoglobin cut-offs based on child ages and anemia severity Age Hemoglobin (g/dL) Mild Anemia Moderate Anemia Severe Anemia 6–59 Months 10-10.9 7-9.9 < 7 5 Months- 11 Years 11-11.4 8-10.9 < 8 12–14 Years 11-11.9 8-10.9 < 8 2.2. CT Scan Analysis All images were acquired using a Canon® Aquilion 16-slice CT scanner with the following parameters: 30–300 mAs, 100 kV, rotation duration of 0.5 seconds, and section thickness of 0.6 mm. All images were reconstructed using a soft tissue standard kernel filter specified by the manufacturer. Selected patients did not receive oral contrast before or during the CT examination. The images were evaluated by two separate blinded expert radiologists, who were unaware of laboratory findings. The images were interpreted on a medical monitor using a preset standard-mediastinum window (window width, 350 HU, window level, 40 HU). To evaluate the CT scans, the radiologists were asked to indicate whether they observed the "aortic ring sign" (a hyper-attenuating aortic wall against a relatively hypodense blood pool) and the "interventricular septum sign" (a hyper-attenuating interventricular septum against a hypodense blood pool). Additionally, objective measurements of blood density were done by placing circular regions of interest (ROI) over various structures, including the ascending and descending aorta, aortic arch, main pulmonary artery, and inferior vena cava (IVC). 2.3. Statistical Analysis The data was analyzed using IBM SPSS Statistics Version 25. Linear regression analysis was used to evaluate the relationship between HU numbers and Hb level. The receiver operating characteristic (ROC) analysis was performed to diagnose anemia with a high R-value group correlation coefficient in selected cases. Sensitivity, specificity, and accuracy were calculated for subjective and objective analyses. A p-value < 0.05 was considered statistically significant. 3. Results The study included two hundred eighty-one patients, of whom 157 (55.87%) were males. The mean age was 6.24 ± 4.06 years (6 months at minimum and 14 years old at maximum). The mean Hb level in our studied population was 10.61 ± 1.92 g/dL (ranging from 5.5 to 16.8). Analysis indicated that 107 (38.1%) of the studied population had no criteria for anemia, while the rest presented various anemia levels. In detail, the prevalence of mild, moderate, and severe anemia in the participants was 34 (12.1%), 126 (44.8%), and 14 (5%) individuals, respectively. Additionally, 104 (37%) cases represented the aortic rim sign, and 79 (28.1%) represented the interventricular septum sign. Dividing the study population into anemic and non-anemic cases revealed that there are no significant differences between anemic and non-anemic cases ages (6.55 ± 4.23 v.s 5.72 ± 3.73; P = 0.09); however, CT scan parameters including the aortic arch, ascending aorta, descending aorta, pulmonary trunk, and IVC densities were all have significant differences in these two groups (P < 0.0001) (Tables 2 ). Table 2 Age and mean blood attenuation in various anatomic locations in the studied population Variable Total population (mean ± SD) Non-Anemic (mean ± SD) Anemic (mean ± SD) P-value Age (years) 6.24 ± 4.06 5.72 ± 3.73 6.55 ± 4.23 0.09 Aortic Arch (HU) 40.05 ± 8.47 43.22 ± 8.00 38.10 ± 8.17 < 0.0001 Ascending Aorta (HU) 39.35 ± 8.26 42.54 ± 7.73 37.39 ± 7.99 < 0.0001 Descending Aorta (HU) 39.52 ± 8.65 42.62 ± 7.80 37.61 ± 8.62 < 0.0001 Pulmonary Trunk (HU) 38.91 ± 9.57 42.41 ± 9.18 36.75 ± 9.18 < 0.0001 IVC (HU) 39.19 ± 8.09 42.02 ± 8.22 37.447.51 < 0.0001 IVC: Inferior Vena Cava Further analysis of the specific markers, including the aortic rim sign and interventricular septum sign, revealed significant differences in the anemic cases compared to non-anemic cases (P = 0.05 and P = 0.001, respectively) (Table 3 ). Table 3 Aortic rim sign and Interventricular septum sign comparison in anemic and non-anemic cases. Variable Non-Anemic (%) Anemic (%) P-value Aortic rim sign Positive 32 (11.4) 72 (25.6) 0.05 Negative 75 (26.7) 102 (36.3) Interventricular septum sign Positive 18 (6.4) 61 (21.7) 0.001 Negative 89 (31.7) 113 (40.2) The results of the ROC analysis are shown in Fig. 1 . The area under the ROC curve was 0.66 for the HU value in the aortic arch, 0.67 in the ascending aorta, 0.66 in the descending aorta, 0.67 in the pulmonary artery, and 0.65 in the IVC. However, comparing the severe anemic with other conditions revealed that the area under curve as follows: 0.57 for the HU value in the aortic arch, 0.60 in the ascending aorta, 0.62 in the descending aorta, 0.65 in the pulmonary artery, and 0.66 in the IVC. Following these findings, Table 4 represents the diagnostic values of the CT scan markers in the diagnosis of anemia. Table 4 Diagnostic values of anemia and severe anemia due to blood CT attenuation in different anatomic locations </caption CT scan marker Area under curve 95% CI Sensitivity (%) Specificity (%) Positive predictive value (%) Negative predictive value (%) Optimal value Anemic v.s non-anemic cases Aortic Arch 0.66 0.60–0.73 0.53 0.72 0.76 0.49 39.5 Ascending Aorta 0.67 0.60–0.73 0.75 0.49 0.71 0.55 42.5 Pulmonary Artery 0.67 0.61–0.76 0.69 0.58 0.73 0.53 40.5 Descending Aorta 0.66 0.60–0.73 0.69 0.58 0.73 0.53 40.5 IVC 0.65 0.59–0.72 0.68 0.55 0.71 0.51 40.5 Severe anemic v.s other conditions Aortic Arch 0.57 0.41–0.73 0.57 0.60 0.07 0.96 38.5 Ascending Aorta 0.60 0.45–0.75 0.85 0.34 0.06 0.98 42.5 Pulmonary Artery 0.65 0.50–0.81 0.64 0.71 0.10 0.97 34.5 Descending Aorta 0.62 0.46–0.77 0.64 0.71 0.10 0.97 34.5 IVC 0.66 0.50–0.81 0.85 0.42 0.07 0.98 40.5 Additionally, aortic rim sign revealed 41.37% (95%CI: 33.98–49.08%) Sensitivity and 69.81% (95%CI: 60.58–78.56) Specificity, while interventricular septum sign represented 35.06% (95%CI: 27.99–42.64) and 83% ((95%CI: 74.72–89.71) of Sensitivity and Specificity, respectively (Table 5 ). Table 5 Diagnostic values of anemia due to interventricular septum sign and aortic rim sign Variable Interventricular septum sign Aortic rim sign Optimal Value 0.5 0.5 Sensitivity (%) 35.05 41.37 Specificity (%) 83 69.81 Positive predictive value (%) 77.21 69.21 Negative predictive value (%) 43.78 42.04 Accuracy 59.04 (53.99–64.09) 55.6 (49.78–61.32) Furthermore, linear and logestic regression models revealed that severe anemia would have significant effects on both blood CT attenuation in different anatomic locations and CT scan markers in the studied population (P < 0.05); except in aortic rim sign (P = 0.54) (Table 6 ). Table 6 Linear and logestic regression models for the severe anemia in the studied population Variable B Beta 95% confidence interval P-value Linear regression model analysis Aortic Arch (HU) -5.121 -0.294 -7.08 to -3.15 < 0.0001 Ascending Aorta (HU) -5.151 -0.303 -7.06 to -3.24 < 0.0001 Descending Aorta (HU) -5.008 -0.281 -7.02 to -2.99 < 0.0001 Pulmonary Trunk (HU) -5.65 -0.287 -7.88 to -3.43 < 0.0001 IVC (HU) -4.57 -0.275 -6.46 to -2.69 < 0.0001 Logestic regression model analysis Variable B OR 95% confidence interval P-value Interventricular septum sign 0.982 2.66 1.47 to 4.83 0.001 Aortic rim sign 0.503 1.65 0.99 to 2.76 0.54 4. Discussion As previously mentioned, anemia is recognized not only as a highly prevalent medical condition but also as a frequently overlooked and underdiagnosed entity that poses an elevated risk of mortality, morbidity, and prolonged hospitalization (18). Therefore, considering any potential means of detecting anemia could be helpful in clinical practice. The present study aimed to evaluate the role of non-contrast thoracic CT scans in anemia diagnosis in infants and children by investigating 281 subjects. In addition to the objective measurements, the subjective evaluations demonstrated acceptable specificity in the detection of anemia. In detail, the interventricular septum sign revealed an acceptable specificity (83%) in detecting anemia, while its sensitivity was reported as 35.06%. Additionally, the aortic rim sign was not as specified as the interventricular septum sign; in fact, a reported reported 69.81% specificity of the aortic rim sign, besides its low sensitivity (41.37%), makes some points of uncertainty about the role of chest CT scan in diagnosing anemia in the studied population. Additionally, the area under the ROC curve was 0.66 for the HU value in the aortic arch, 0.67 in the ascending aorta, 0.66 in the descending aorta, 0.67 in the pulmonary artery, and 0.65 in the IVC. However, comparing the severe anemic with other conditions revealed that the area under curve as follows: 0.57 for the HU value in the aortic arch, 0.60 in the ascending aorta, 0.62 in the descending aorta, 0.65 in the pulmonary artery, and 0.66 in the IVC. Further regression model analysis indicated that blood density in the pulmonary trunk and aortic arch has the most effects in severe anemia (B=-5.65 and − 5.121; P < 0.0001 and < 0.0001, respectively). Despite the logistic regression analysis represented that the interventricular septum sign significantly related to the severe anemia (OR = 2.66, 95%CI = 1.47 to 4.83, P = 0.001), the aortic rim sign did not presented a significant relationship (OR = 1.65, 95%CI = 0.99 to 2.76, P = 0.54). This study is the first, to our knowledge, to explore the role of chest CT scans in detecting anemia in pediatrics. A glance at the previous knowledge in this field determined that previous studies have reported various findings about the role of chest CT scans in anemia detection in adults. Abbasi et al. reported that the aortic ring sign was more sensitive (82.5%) than the interventricular septum sign (32%) in detecting anemia, whereas the latter character was more specific (87% and 99.2%, respectively) (13). Despite their study evaluating adult subjects, it suggested that detecting anemia from an unenhanced chest CT scan is possible. Both objective and subjective criteria show promising sensitivity and specificity. Kamel et al. used a threshold of less than 35 HU for anemia diagnosis, and the sensitivity and specificity of aortic CT attenuation values were 84% and 94%, respectively (19). Additionally, Zhou et al. determined that once the CT value was more than 13.5 HU, the sensitivity and specificity for diagnosing severe anemia in all genders were exquisite (94.7% and 83.6% in males; 82.4% and 84.6% in females) (14). The difference between studies could be due to their differences in the studied population- as we investigated children while others studied adults- differences in the imaging methods, including CT scan machine properties, and differences in reading and interpretation of the images. Furthermore, the superior sensitivity of the aortic ring sign can be attributed to the greater contrast between the aortic wall, consisting mainly of collagen and elastin fibers, and the blood pool. The attenuation between myocardial and blood pool is less contrasting, resulting in decreased sensitivity of the interventricular septum sign. The decreased specificity of the aortic ring sign may arise from false-positive interpretations in cases of early calcium depositions, leading to increased density of the aortic wall on CT scans. To put it differently, when considering subjective analysis, the presence of an interventricular septum sign can serve as a dependable diagnostic indicator for anemia, while the absence of an aortic ring sign can reliably exclude the presence of anemia. Consequently, a swift examination of these two findings can be conducted as part of the routine evaluation of chest CT scans. Determining anemia from chest CT scans in children presents both challenges and opportunities. While CT scans are not typically used as the primary method for diagnosing anemia, they can sometimes reveal specific findings that may suggest anemia. In specific contexts, such as acute conditions where immediate assessment is crucial, CT scans might be considered part of the diagnostic process (20). It is worth noting that when interpreting CT scans to assess for anemia, subjective and objective approaches can be employed. Subjective assessments might involve looking for specific visual indicators, such as the "aortic ring sign" and "interventricular septum sign," which are characterized by deviations in the attenuation of blood and surrounding structures. These signs, while helpful, are subject to interpretation and observer variability (21). Additionally, objective assessments can be performed by measuring the blood density within specified areas of interest on the CT images. These quantitative measurements can provide a more standardized approach to gauge potential anemia. However, it is essential to recognize that while CT scans can reveal suggestive findings; they are generally not substitutes for traditional methods of diagnosing anemia, such as blood tests to assess hemoglobin levels and red blood cell counts (22). In instances where anemia is suspected based on CT findings, further confirmatory tests, such as blood tests, would typically be necessary to establish a definitive diagnosis of anemia in children. As with any medical diagnostic procedure, consulting with healthcare professionals specialized in pediatric care is essential for appropriate evaluation and management based on the specific clinical scenario (23, 24). The present study was limited in some issues, including that the studied subjects were not categorized due to their underlying conditions and past medical histories, indices such as the HU: Hb ratio were not calculated for the studied subjects, and we were unable to indicate the blood attenuation in further anatomical locations in the studied chest CT scans. 5. Conclusions The detection of anemia is possible through the use of an unenhanced chest CT scan. Both objective and subjective criteria show values of sensitivity and specificity; however, in some cases, it would not be reliable. Additionally, a chest CT scan would be more accurate in detecting severe anemia. Moreover, the attenuation of mediastinal vessels had an excellent negative predictive value to evaluate severe anemia; therefore, it can be concluded that the attenuation of mediastinal vessels can rule out the presence of severe anemia with a very high probability. Abbreviations Hemoglobin (Hb) Computed Tomography (CT) Interventricular Septum (IVS) Left Ventricle Cavity (LV) Complete Blood Count (CBC) World Health Organization (WHO) Regions of Interest (ROI) Inferior Vena Cava (IVC) Receiver Operating Characteristic (ROC) Declarations Availability of data and materials The datasets created during the current study are not publicly accessible due to the possibility of compromising the privacy of individuals. According to the written approval forms accepted by the Ethics Committee of Mashhad University of Medical Sciences, the data were only available to researchers within the project. The data would be available upon request from the corresponding authors. Acknowledgments Not applicable Funding None Ethics approval and consent to participate The Ethics Committee of the Mashhad University of Medical Sciences, Mashhad, Iran, approved this retrospective observational study. The review board at MUMS waived informed consent due to the observational nature of the research under the waiver statement (Ethical code: IR.MUMS.MEDICAL.REC.1401.284). Consent for publication None Competing interests The authors declare that they have no competing interests. Authors' contributions: Conceptualization: Mostafa Jafarpour, Ehsan Hassannejad, Navid Zavvar, Kimia Tarrah, Asma Payandeh, Masoud Mahdavi Rashed; Methodology: Kimia Tarrah; Investigation, Supervision, Funding acquisition: Masoud Mahdavi Rashed; Writing original draft: Mostafa Jafarpour, Ehsan Hassannejad; Writing - review & editing: Mostafa Jafarpour, Ehsan Hassannejad, Navid Zavvar, Kimia Tarrah, Asma Payandeh, Masoud Mahdavi Rashed References Kassebaum NJ, Jasrasaria R, Naghavi M, Wulf SK, Johns N, Lozano R, et al. A systematic analysis of global anemia burden from 1990 to 2010. Blood, the Journal of the American Society of Hematology. 2014;123(5):615 − 24. Khan L. Anemia in childhood. Pediatric annals. 2018;47(2):e42-e7. Andriastuti M, Ilmana G, Nawangwulan SA, Kosasih KA. Prevalence of anemia and iron profile among children and adolescent with low socio-economic status. International Journal of Pediatrics and Adolescent Medicine. 2020;7(2):88–92. Collaborators GA. 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Comparison between thoracic low-dose computed tomography and conventional-dose computed tomography in evaluating anemia: A preliminary study in a Chinese screening cohort. Frontiers in Cardiovascular Medicine. 2022;9:987753. Desaint P, Bernard C, Contou D. Diagnosing anemia with chest CT-scan: the aortic ring sign. The American Journal of the Medical Sciences. 2022;363(2):e17. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7508114","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":513749786,"identity":"0711d4bb-9800-4a2b-adf6-9d800ae19448","order_by":0,"name":"Masoud Mahdavi Rashed","email":"","orcid":"","institution":"Mashhad University of Medical Sciences","correspondingAuthor":false,"prefix":"","firstName":"Masoud","middleName":"Mahdavi","lastName":"Rashed","suffix":""},{"id":513749787,"identity":"7e6969bb-10a3-4d2d-ac5e-eb9ab40cd1f8","order_by":1,"name":"Ehsan Hassannejad","email":"","orcid":"","institution":"Birjand University of Medical Sciences","correspondingAuthor":false,"prefix":"","firstName":"Ehsan","middleName":"","lastName":"Hassannejad","suffix":""},{"id":513749788,"identity":"0fff68c3-3f79-4ed6-ab75-85588e28194d","order_by":2,"name":"Navid Zavvar","email":"","orcid":"","institution":"Mashhad University of Medical Sciences","correspondingAuthor":false,"prefix":"","firstName":"Navid","middleName":"","lastName":"Zavvar","suffix":""},{"id":513749789,"identity":"6f83f2de-a45e-4126-a3d7-f0d293367eb7","order_by":3,"name":"Kimia Tarrah","email":"","orcid":"","institution":"Mashhad University of Medical Sciences","correspondingAuthor":false,"prefix":"","firstName":"Kimia","middleName":"","lastName":"Tarrah","suffix":""},{"id":513749790,"identity":"5e89a1dc-2b21-42d5-b56a-cbff5dd60f9f","order_by":4,"name":"Asma Payandeh","email":"","orcid":"","institution":"Mashhad University of Medical Sciences","correspondingAuthor":false,"prefix":"","firstName":"Asma","middleName":"","lastName":"Payandeh","suffix":""},{"id":513749791,"identity":"9170a798-db66-4b47-b831-c2264a8aa6e9","order_by":5,"name":"Mostafa Jafarpour","email":"data:image/png;base64,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","orcid":"","institution":"Mashhad University of Medical Sciences","correspondingAuthor":true,"prefix":"","firstName":"Mostafa","middleName":"","lastName":"Jafarpour","suffix":""}],"badges":[],"createdAt":"2025-09-01 11:53:38","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7508114/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7508114/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":91816908,"identity":"a8f0111f-2fdb-4d0e-99ac-85aa159fd92d","added_by":"auto","created_at":"2025-09-22 06:52:57","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":234194,"visible":true,"origin":"","legend":"","description":"","filename":"Anemiafinal22egypt.docx","url":"https://assets-eu.researchsquare.com/files/rs-7508114/v1/5992ae81668b375202b52a18.docx"},{"id":91486858,"identity":"4a592ea2-1128-4061-80b6-4d8e4258078a","added_by":"auto","created_at":"2025-09-17 04:58:59","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":175588,"visible":true,"origin":"","legend":"\u003cp\u003eResults were obtained using receiver operating characteristic (ROC) analysis considering anemic and non-anemic cases. IVC: inferior vena cava. A: comparing anemic and non-anemic cases. B: comparing severe anemic and other conditions\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7508114/v1/b7cea5dffaf700421bb23dec.png"},{"id":97249723,"identity":"aa07b82f-f47b-4746-99c3-d984d5d14cfe","added_by":"auto","created_at":"2025-12-02 13:13:17","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1080053,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7508114/v1/301d5960-9937-4ce6-8e6b-c141ebe6d36f.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Detecting Anemia in Pediatrics by unenhanced thoracic Computed Tomography Scan","fulltext":[{"header":"1. Background","content":"\u003cp\u003eAnemia is known as the reduced number of red blood cells in the human circulation, which can clinically be represented by the decreased serum hemoglobin (Hb) concentration in complete blood count analysis (1); in detail, the definition of anemia involves a decline in hemoglobin or hematocrit levels below the 2.5th percentile for age, race, and sex (2). According to the latest research, anemia is not only a common health problem worldwide but also a condition that can give rise to a diverse range of morbidities, thus posing a substantial global health concern (3). The global incidence of anemia affects roughly two million individuals, which constitutes almost a quarter of the worldwide population. (4). According to our current knowledge, children who have anemia may experience adverse effects on their cognitive and motor development, making them more vulnerable to infections. The enhanced susceptibility to infections, including life-threatening ones like malaria, can potentially amplify the risk of childhood mortality (5, 6). Furthermore, anemia may contribute to an elevated likelihood of hospitalization, unfavorable prognosis for both medical and surgical results, and heightened mortality across all causes (7).\u003c/p\u003e\u003cp\u003eThe computed tomography (CT) scan is a medical imaging technique that is commonly utilized for non-invasive visualization and diagnosis of various conditions affecting different body parts (8, 9, 10). It is not uncommon for CT scans to reveal incidental findings; while some of them could not be important to pay attention to, some others have a considerable impact on patients\u0026rsquo; management and outcomes (11). Few previous reports have highlighted that anemia can be incidentally detected during unenhanced thoracic CT scans (12). This implies that anemia, a condition characterized by low red blood cell levels, can be detected through chest CT scans, even if the primary purpose of the scan is unrelated to evaluating anemia (13). In acute conditions, such as in trauma patients, there is often limited time to wait for peripheral blood test analysis. In these situations, obtaining a diagnosis through a CT scan, which is commonly performed, can be highly beneficial. It is imperative because non-contrast chest CT scans may reveal specific findings that can suggest the presence of anemia. Examples of these findings include a relatively dense interventricular septum (known as the septal sign), differences in CT attenuation between the interventricular septum and left ventricle cavity (IVS-LV), or a relatively hyper-attenuating aortic wall (the aortic ring sign) (14, 15). These findings are subjective and reader-dependent and subject to significant inter-observer variability.\u003c/p\u003e\u003cp\u003eIn addition, it is essential to note that certain conditions, like glycogen or iron storage diseases, can lead to findings that may falsely indicate anemia (16). On the other hand, objective analysis offers a more precise evaluation of anemia. A more accurate assessment of anemia can be made by measuring the attenuation value, which represents a reproducible physical density measurement and can be obtained from a standard CT examination. It is worth mentioning that there is no established cut-off in blood attenuation on non-contrast chest CT scans to suggest the definitive presence of anemia. To address it, the current study evaluated the diagnostic accuracy of subjective and objective criteria for diagnosing anemia on an unenhanced thoracic CT scan in infants and children.\u003c/p\u003e"},{"header":"2. Methods","content":"\u003cp\u003eThe present retrospective cross-sectional study was conducted on eligible patients admitted to Imam Reza and Ghaem Hospitals as academic hospitals of Mashhad University of Medical Sciences, Mashhad, Iran. The Ethics committee of Mashhad University of Medical Sciences, Mashhad, Iran approved this retrospective observational study. The review board at MUMS waived informed consent due to the observational nature of the research, under the waiver statement (ETHICAL CODE: IR.MUMS.MEDICAL.REC.1401.284).\u003c/p\u003e\u003cp\u003eThe sample size was calculated at a minimum of 240 cases due to Zohu et al.'s (14) study by considering the power as 80% and the confidence interval as 95%.\u003c/p\u003e\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003e2.1. Patient selection\u003c/h2\u003e\u003cp\u003ePatients under 18 years old with documented non-contrast chest CT scan and complete blood count (CBC) evaluation within 24 hours of unenhanced thoracic CT scan who were admitted to \u0026hellip; pediatrics' Hospitals, were included in the present study; however, documents with significant artifact in the chest CT scan and who received blood product transfusion were excluded. Clinical assessment, laboratory investigations, and unenhanced thoracic CT scans were reviewed for each patient.\u003c/p\u003e\u003cp\u003eAnemia was defined based on the World Health Organization (WHO) definitions (17) (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eHemoglobin cut-offs based on child ages and anemia severity\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\"\u0026minus;\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\"\u0026minus;\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eAge\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e\u003cp\u003eHemoglobin (g/dL)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMild Anemia\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eModerate Anemia\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSevere Anemia\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003e6\u0026ndash;59 Months\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026minus;\" colname=\"c2\"\u003e\u003cp\u003e10-10.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026minus;\" colname=\"c3\"\u003e\u003cp\u003e7-9.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;7\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003e5 Months- 11 Years\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026minus;\" colname=\"c2\"\u003e\u003cp\u003e11-11.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026minus;\" colname=\"c3\"\u003e\u003cp\u003e8-10.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003e12\u0026ndash;14 Years\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026minus;\" colname=\"c2\"\u003e\u003cp\u003e11-11.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026minus;\" colname=\"c3\"\u003e\u003cp\u003e8-10.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\u003ch2\u003e2.2. CT Scan Analysis\u003c/h2\u003e\u003cp\u003eAll images were acquired using a Canon\u0026reg; Aquilion 16-slice CT scanner with the following parameters: 30\u0026ndash;300 mAs, 100 kV, rotation duration of 0.5 seconds, and section thickness of 0.6 mm. All images were reconstructed using a soft tissue standard kernel filter specified by the manufacturer. Selected patients did not receive oral contrast before or during the CT examination.\u003c/p\u003e\u003cp\u003eThe images were evaluated by two separate blinded expert radiologists, who were unaware of laboratory findings. The images were interpreted on a medical monitor using a preset standard-mediastinum window (window width, 350 HU, window level, 40 HU). To evaluate the CT scans, the radiologists were asked to indicate whether they observed the \"aortic ring sign\" (a hyper-attenuating aortic wall against a relatively hypodense blood pool) and the \"interventricular septum sign\" (a hyper-attenuating interventricular septum against a hypodense blood pool). Additionally, objective measurements of blood density were done by placing circular regions of interest (ROI) over various structures, including the ascending and descending aorta, aortic arch, main pulmonary artery, and inferior vena cava (IVC).\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\u003ch2\u003e2.3. Statistical Analysis\u003c/h2\u003e\u003cp\u003eThe data was analyzed using IBM SPSS Statistics Version 25. Linear regression analysis was used to evaluate the relationship between HU numbers and Hb level. The receiver operating characteristic (ROC) analysis was performed to diagnose anemia with a high R-value group correlation coefficient in selected cases. Sensitivity, specificity, and accuracy were calculated for subjective and objective analyses. A p-value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant.\u003c/p\u003e\u003c/div\u003e"},{"header":"3. Results","content":"\u003cp\u003eThe study included two hundred eighty-one patients, of whom 157 (55.87%) were males. The mean age was 6.24\u0026thinsp;\u0026plusmn;\u0026thinsp;4.06 years (6 months at minimum and 14 years old at maximum). The mean Hb level in our studied population was 10.61\u0026thinsp;\u0026plusmn;\u0026thinsp;1.92 g/dL (ranging from 5.5 to 16.8). Analysis indicated that 107 (38.1%) of the studied population had no criteria for anemia, while the rest presented various anemia levels. In detail, the prevalence of mild, moderate, and severe anemia in the participants was 34 (12.1%), 126 (44.8%), and 14 (5%) individuals, respectively. Additionally, 104 (37%) cases represented the aortic rim sign, and 79 (28.1%) represented the interventricular septum sign.\u003c/p\u003e\u003cp\u003eDividing the study population into anemic and non-anemic cases revealed that there are no significant differences between anemic and non-anemic cases ages (6.55\u0026thinsp;\u0026plusmn;\u0026thinsp;4.23 v.s 5.72\u0026thinsp;\u0026plusmn;\u0026thinsp;3.73; P\u0026thinsp;=\u0026thinsp;0.09); however, CT scan parameters including the aortic arch, ascending aorta, descending aorta, pulmonary trunk, and IVC densities were all have significant differences in these two groups (P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001) (Tables\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eAge and mean blood attenuation in various anatomic locations in the studied population\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVariable\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTotal population\u003c/p\u003e\u003cp\u003e(mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eNon-Anemic\u003c/p\u003e\u003cp\u003e(mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eAnemic\u003c/p\u003e\u003cp\u003e(mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eP-value\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAge (years)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e\u003cp\u003e6.24\u0026thinsp;\u0026plusmn;\u0026thinsp;4.06\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e\u003cp\u003e5.72\u0026thinsp;\u0026plusmn;\u0026thinsp;3.73\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e6.55\u0026thinsp;\u0026plusmn;\u0026thinsp;4.23\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.09\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAortic Arch (HU)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e\u003cp\u003e40.05\u0026thinsp;\u0026plusmn;\u0026thinsp;8.47\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e\u003cp\u003e43.22\u0026thinsp;\u0026plusmn;\u0026thinsp;8.00\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e38.10\u0026thinsp;\u0026plusmn;\u0026thinsp;8.17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAscending Aorta (HU)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e\u003cp\u003e39.35\u0026thinsp;\u0026plusmn;\u0026thinsp;8.26\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e\u003cp\u003e42.54\u0026thinsp;\u0026plusmn;\u0026thinsp;7.73\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e37.39\u0026thinsp;\u0026plusmn;\u0026thinsp;7.99\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eDescending Aorta (HU)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e\u003cp\u003e39.52\u0026thinsp;\u0026plusmn;\u0026thinsp;8.65\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e\u003cp\u003e42.62\u0026thinsp;\u0026plusmn;\u0026thinsp;7.80\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e37.61\u0026thinsp;\u0026plusmn;\u0026thinsp;8.62\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePulmonary Trunk (HU)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e\u003cp\u003e38.91\u0026thinsp;\u0026plusmn;\u0026thinsp;9.57\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e\u003cp\u003e42.41\u0026thinsp;\u0026plusmn;\u0026thinsp;9.18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e36.75\u0026thinsp;\u0026plusmn;\u0026thinsp;9.18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eIVC (HU)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e\u003cp\u003e39.19\u0026thinsp;\u0026plusmn;\u0026thinsp;8.09\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e\u003cp\u003e42.02\u0026thinsp;\u0026plusmn;\u0026thinsp;8.22\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e37.447.51\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"5\"\u003eIVC: Inferior Vena Cava\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eFurther analysis of the specific markers, including the aortic rim sign and interventricular septum sign, revealed significant differences in the anemic cases compared to non-anemic cases (P\u0026thinsp;=\u0026thinsp;0.05 and P\u0026thinsp;=\u0026thinsp;0.001, respectively) (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eAortic rim sign and Interventricular septum sign comparison in anemic and non-anemic cases.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eVariable\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eNon-Anemic (%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eAnemic (%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eP-value\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eAortic rim sign\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePositive\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e32 (11.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e72 (25.6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.05\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNegative\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e75 (26.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e102 (36.3)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003eInterventricular septum sign\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePositive\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e18 (6.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e61 (21.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNegative\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e89 (31.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e113 (40.2)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eThe results of the ROC analysis are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. The area under the ROC curve was 0.66 for the HU value in the aortic arch, 0.67 in the ascending aorta, 0.66 in the descending aorta, 0.67 in the pulmonary artery, and 0.65 in the IVC. However, comparing the severe anemic with other conditions revealed that the area under curve as follows: 0.57 for the HU value in the aortic arch, 0.60 in the ascending aorta, 0.62 in the descending aorta, 0.65 in the pulmonary artery, and 0.66 in the IVC. Following these findings, Table \u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e represents the diagnostic values of the CT scan markers in the diagnosis of anemia.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eDiagnostic values of anemia and severe anemia due to blood CT attenuation in different anatomic locations\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003ccolgroup cols=\"9\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u003cp\u003eCT scan marker\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eArea under curve\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e95% CI\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eSensitivity (%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eSpecificity (%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003ePositive predictive value (%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e\u003cp\u003eNegative predictive value (%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c9\"\u003e\u003cp\u003eOptimal value\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"4\" rowspan=\"5\"\u003e\u003cp\u003e\u003cb\u003eAnemic v.s non-anemic cases\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAortic Arch\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.66\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.60\u0026ndash;0.73\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.53\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.72\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.76\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e0.49\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e39.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAscending Aorta\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.67\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.60\u0026ndash;0.73\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.49\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.71\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e0.55\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e42.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePulmonary Artery\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.67\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.61\u0026ndash;0.76\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.69\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.58\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.73\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e0.53\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e40.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eDescending Aorta\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.66\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.60\u0026ndash;0.73\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.69\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.58\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.73\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e0.53\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e40.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eIVC\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.65\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.59\u0026ndash;0.72\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.68\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.55\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.71\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e0.51\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e40.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"4\" rowspan=\"5\"\u003e\u003cp\u003e\u003cb\u003eSevere anemic v.s other conditions\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAortic Arch\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.57\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.41\u0026ndash;0.73\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.57\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.07\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e0.96\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e38.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAscending Aorta\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.45\u0026ndash;0.75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.85\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.34\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.06\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e0.98\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e42.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePulmonary Artery\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.65\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.50\u0026ndash;0.81\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.64\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.71\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e0.97\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e34.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eDescending Aorta\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.62\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.46\u0026ndash;0.77\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.64\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.71\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e0.97\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e34.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eIVC\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.66\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.50\u0026ndash;0.81\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.85\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.42\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.07\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e0.98\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e40.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eAdditionally, aortic rim sign revealed 41.37% (95%CI: 33.98\u0026ndash;49.08%) Sensitivity and 69.81% (95%CI: 60.58\u0026ndash;78.56) Specificity, while interventricular septum sign represented 35.06% (95%CI: 27.99\u0026ndash;42.64) and 83% ((95%CI: 74.72\u0026ndash;89.71) of Sensitivity and Specificity, respectively (Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eDiagnostic values of anemia due to interventricular septum sign and aortic rim sign\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"3\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVariable\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eInterventricular septum sign\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eAortic rim sign\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eOptimal Value\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eSensitivity (%)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e35.05\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e41.37\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eSpecificity (%)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e83\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e69.81\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePositive predictive value (%)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e77.21\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e69.21\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eNegative predictive value (%)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e43.78\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e42.04\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAccuracy\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e59.04 (53.99\u0026ndash;64.09)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e55.6 (49.78\u0026ndash;61.32)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eFurthermore, linear and logestic regression models revealed that severe anemia would have significant effects on both blood CT attenuation in different anatomic locations and CT scan markers in the studied population (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05); except in aortic rim sign (P\u0026thinsp;=\u0026thinsp;0.54) (Table\u0026nbsp;\u003cspan refid=\"Tab6\" class=\"InternalRef\"\u003e6\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab6\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 6\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eLinear and logestic regression models for the severe anemia in the studied population\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVariable\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eB\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eBeta\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e95% confidence interval\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eP-value\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"5\" nameend=\"c5\" namest=\"c1\"\u003e\u003cp\u003e\u003cb\u003eLinear regression model analysis\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAortic Arch (HU)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-5.121\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e-0.294\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-7.08 to -3.15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAscending Aorta (HU)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-5.151\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e-0.303\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-7.06 to -3.24\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eDescending Aorta (HU)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-5.008\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e-0.281\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-7.02 to -2.99\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePulmonary Trunk (HU)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-5.65\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e-0.287\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-7.88 to -3.43\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eIVC (HU)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-4.57\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e-0.275\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e-6.46 to -2.69\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.0001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"5\" nameend=\"c5\" namest=\"c1\"\u003e\u003cp\u003e\u003cb\u003eLogestic regression model analysis\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVariable\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eB\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eOR\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e95% confidence interval\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eP-value\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eInterventricular septum sign\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.982\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2.66\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.47 to 4.83\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eAortic rim sign\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.503\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.65\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.99 to 2.76\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.54\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e"},{"header":"4. Discussion","content":"\u003cp\u003eAs previously mentioned, anemia is recognized not only as a highly prevalent medical condition but also as a frequently overlooked and underdiagnosed entity that poses an elevated risk of mortality, morbidity, and prolonged hospitalization (18). Therefore, considering any potential means of detecting anemia could be helpful in clinical practice. The present study aimed to evaluate the role of non-contrast thoracic CT scans in anemia diagnosis in infants and children by investigating 281 subjects. In addition to the objective measurements, the subjective evaluations demonstrated acceptable specificity in the detection of anemia. In detail, the interventricular septum sign revealed an acceptable specificity (83%) in detecting anemia, while its sensitivity was reported as 35.06%. Additionally, the aortic rim sign was not as specified as the interventricular septum sign; in fact, a reported reported 69.81% specificity of the aortic rim sign, besides its low sensitivity (41.37%), makes some points of uncertainty about the role of chest CT scan in diagnosing anemia in the studied population. Additionally, the area under the ROC curve was 0.66 for the HU value in the aortic arch, 0.67 in the ascending aorta, 0.66 in the descending aorta, 0.67 in the pulmonary artery, and 0.65 in the IVC. However, comparing the severe anemic with other conditions revealed that the area under curve as follows: 0.57 for the HU value in the aortic arch, 0.60 in the ascending aorta, 0.62 in the descending aorta, 0.65 in the pulmonary artery, and 0.66 in the IVC. Further regression model analysis indicated that blood density in the pulmonary trunk and aortic arch has the most effects in severe anemia (B=-5.65 and \u0026minus;\u0026thinsp;5.121; P\u0026thinsp;\u0026lt;\u0026thinsp;0.0001 and \u0026lt;\u0026thinsp;0.0001, respectively). Despite the logistic regression analysis represented that the interventricular septum sign significantly related to the severe anemia (OR\u0026thinsp;=\u0026thinsp;2.66, 95%CI\u0026thinsp;=\u0026thinsp;1.47 to 4.83, P\u0026thinsp;=\u0026thinsp;0.001), the aortic rim sign did not presented a significant relationship (OR\u0026thinsp;=\u0026thinsp;1.65, 95%CI\u0026thinsp;=\u0026thinsp;0.99 to 2.76, P\u0026thinsp;=\u0026thinsp;0.54).\u003c/p\u003e\u003cp\u003eThis study is the first, to our knowledge, to explore the role of chest CT scans in detecting anemia in pediatrics. A glance at the previous knowledge in this field determined that previous studies have reported various findings about the role of chest CT scans in anemia detection in adults. Abbasi et al. reported that the aortic ring sign was more sensitive (82.5%) than the interventricular septum sign (32%) in detecting anemia, whereas the latter character was more specific (87% and 99.2%, respectively) (13). Despite their study evaluating adult subjects, it suggested that detecting anemia from an unenhanced chest CT scan is possible. Both objective and subjective criteria show promising sensitivity and specificity. Kamel et al. used a threshold of less than 35 HU for anemia diagnosis, and the sensitivity and specificity of aortic CT attenuation values were 84% and 94%, respectively (19). Additionally, Zhou et al. determined that once the CT value was more than 13.5 HU, the sensitivity and specificity for diagnosing severe anemia in all genders were exquisite (94.7% and 83.6% in males; 82.4% and 84.6% in females) (14). The difference between studies could be due to their differences in the studied population- as we investigated children while others studied adults- differences in the imaging methods, including CT scan machine properties, and differences in reading and interpretation of the images. Furthermore, the superior sensitivity of the aortic ring sign can be attributed to the greater contrast between the aortic wall, consisting mainly of collagen and elastin fibers, and the blood pool. The attenuation between myocardial and blood pool is less contrasting, resulting in decreased sensitivity of the interventricular septum sign. The decreased specificity of the aortic ring sign may arise from false-positive interpretations in cases of early calcium depositions, leading to increased density of the aortic wall on CT scans. To put it differently, when considering subjective analysis, the presence of an interventricular septum sign can serve as a dependable diagnostic indicator for anemia, while the absence of an aortic ring sign can reliably exclude the presence of anemia. Consequently, a swift examination of these two findings can be conducted as part of the routine evaluation of chest CT scans.\u003c/p\u003e\u003cp\u003eDetermining anemia from chest CT scans in children presents both challenges and opportunities. While CT scans are not typically used as the primary method for diagnosing anemia, they can sometimes reveal specific findings that may suggest anemia. In specific contexts, such as acute conditions where immediate assessment is crucial, CT scans might be considered part of the diagnostic process (20). It is worth noting that when interpreting CT scans to assess for anemia, subjective and objective approaches can be employed. Subjective assessments might involve looking for specific visual indicators, such as the \"aortic ring sign\" and \"interventricular septum sign,\" which are characterized by deviations in the attenuation of blood and surrounding structures. These signs, while helpful, are subject to interpretation and observer variability (21).\u003c/p\u003e\u003cp\u003eAdditionally, objective assessments can be performed by measuring the blood density within specified areas of interest on the CT images. These quantitative measurements can provide a more standardized approach to gauge potential anemia. However, it is essential to recognize that while CT scans can reveal suggestive findings; they are generally not substitutes for traditional methods of diagnosing anemia, such as blood tests to assess hemoglobin levels and red blood cell counts (22). In instances where anemia is suspected based on CT findings, further confirmatory tests, such as blood tests, would typically be necessary to establish a definitive diagnosis of anemia in children. As with any medical diagnostic procedure, consulting with healthcare professionals specialized in pediatric care is essential for appropriate evaluation and management based on the specific clinical scenario (23, 24).\u003c/p\u003e\u003cp\u003eThe present study was limited in some issues, including that the studied subjects were not categorized due to their underlying conditions and past medical histories, indices such as the HU: Hb ratio were not calculated for the studied subjects, and we were unable to indicate the blood attenuation in further anatomical locations in the studied chest CT scans.\u003c/p\u003e"},{"header":"5. Conclusions","content":"\u003cp\u003eThe detection of anemia is possible through the use of an unenhanced chest CT scan. Both objective and subjective criteria show values of sensitivity and specificity; however, in some cases, it would not be reliable. Additionally, a chest CT scan would be more accurate in detecting severe anemia. Moreover, the attenuation of mediastinal vessels had an excellent negative predictive value to evaluate severe anemia; therefore, it can be concluded that the attenuation of mediastinal vessels can rule out the presence of severe anemia with a very high probability.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eHemoglobin (Hb)\u003c/p\u003e\n\u003cp\u003eComputed Tomography (CT)\u003c/p\u003e\n\u003cp\u003eInterventricular Septum (IVS)\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eLeft Ventricle Cavity (LV)\u003c/p\u003e\n\u003cp\u003eComplete Blood Count (CBC)\u003c/p\u003e\n\u003cp\u003eWorld Health Organization (WHO)\u003c/p\u003e\n\u003cp\u003eRegions of Interest (ROI)\u003c/p\u003e\n\u003cp\u003eInferior Vena Cava (IVC)\u003c/p\u003e\n\u003cp\u003eReceiver Operating Characteristic (ROC)\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets created during the current study are not publicly accessible due to the possibility of compromising the privacy of individuals. According to the written approval forms accepted by the Ethics Committee of Mashhad University of Medical Sciences, the data were only available to researchers within the project. The data would be available upon request from the corresponding authors.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNone\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe Ethics Committee of the Mashhad University of Medical Sciences, Mashhad, Iran, approved this retrospective observational study. The review board at MUMS waived informed consent due to the observational nature of the research under the waiver statement (Ethical code: IR.MUMS.MEDICAL.REC.1401.284).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNone\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors' contributions:\u0026nbsp;\u003c/strong\u003eConceptualization: Mostafa Jafarpour, Ehsan Hassannejad, Navid Zavvar, Kimia Tarrah, Asma Payandeh, Masoud Mahdavi Rashed; Methodology: Kimia Tarrah; Investigation, Supervision, Funding acquisition: Masoud Mahdavi Rashed; Writing original draft: Mostafa Jafarpour, Ehsan Hassannejad; Writing - review \u0026amp; editing: Mostafa Jafarpour, Ehsan Hassannejad, Navid Zavvar, Kimia Tarrah, Asma Payandeh, Masoud Mahdavi Rashed\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003e Kassebaum NJ, Jasrasaria R, Naghavi M, Wulf SK, Johns N, Lozano R, et al. 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The Lancet Haematology. 2023;10(9):e713-e34.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e Scott SP, Chen-Edinboro LP, Caulfield LE, Murray-Kolb LE. The impact of anemia on child mortality: an updated review. Nutrients. 2014;6(12):5915-32.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e Larson LM, Kubes JN, Ram\u0026iacute;rez-Luzuriaga MJ, Khishen S, H. Shankar A, Prado EL. Effects of increased hemoglobin on child growth, development, and disease: a systematic review and meta‐analysis. Annals of the New York Academy of Sciences. 2019;1450(1):83\u0026ndash;104.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e Gavhi F, Kuonza L, Musekiwa A, Motaze NV. Factors associated with mortality in children under five years old hospitalized for Severe Acute Malnutrition in Limpopo province, South Africa, 2014\u0026ndash;2018: A cross-sectional analytic study. PloS one. 2020;15(5):e0232838.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e Kasban H, El-Bendary M, Salama D. A comparative study of medical imaging techniques. International Journal of Information Science and Intelligent System. 2015;4(2):37\u0026ndash;58.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e Abbasi B, Kahani N, Ghalibaf AM, Layegh P, Niroumand S, Akhavan R, et al. Evaluating the diagnostic value of multi-detector brain CT angiography in diagnosing acute cerebral venous thrombosis. Scientific Reports. 2022;12(1):18685.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e Rajabzadeh F, Hassannejad E, Akhlaghipour I, Imen MJ, Babazadeh Baghan A, Goshayeshi L, et al. Differentiating benign and malignant thyroid nodules: A cross-sectional study on the comparison of diagnostic value of ultrasound elastography and fine needle aspiration biopsy. Health Science Reports. 2023;6(10):e1619.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e Van de Wiel J, Wang Y, Xu D, Van der Zaag-Loonen H, Van der Jagt E, Van Klaveren R, et al. Neglectable benefit of searching for incidental findings in the Dutch\u0026ndash;Belgian lung cancer screening trial (NELSON) using low-dose multidetector CT. European radiology. 2007;17:1474-82.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e Goetze S, Pannu HK, Wahl RL. Clinically significant abnormal findings on the \u0026ldquo;nondiagnostic\u0026rdquo; CT portion of low-amperage-CT attenuation-corrected myocardial perfusion SPECT/CT studies. Journal of Nuclear Medicine. 2006;47(8):1312-8.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e Abbasi B, Seyed Hosseini M, Moodi Ghalibaf A, Akhavan R, Emadzadeh M, Bolvardi E. Evaluating anemia on non-contrast thoracic computed tomography. Scientific Reports. 2022;12(1):21380.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e Zhou Q-Q, Yu Y-S, Chen Y-C, Ding B-B, Fang S-Y, Yang X, et al. Optimal threshold for the diagnosis of anemia severity on unenhanced thoracic CT: a preliminary study. European Journal of Radiology. 2018;108:236\u0026thinsp;\u0026minus;\u0026thinsp;41.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e Lan H, Nishihara S, Nishitani H. Accuracy of computed tomography attenuation measurements for diagnosing anemia. Japanese journal of radiology. 2010;28:53\u0026thinsp;\u0026minus;\u0026thinsp;7.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e Wang DQ, Carreras CT, Fiske LM, Austin S, Boree D, Kishnani PS, et al. Characterization and pathogenesis of anemia in glycogen storage disease type Ia and Ib. Genetics in medicine. 2012;14(9):795-9.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e Organization WH. Haemoglobin concentrations for the diagnosis of anaemia and assessment of severity. World Health Organization; 2011.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e Goodnough LT, Schrier SL. Evaluation and management of anemia in the elderly. American journal of hematology. 2014;89(1):88\u0026ndash;96.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e Kamel EM, Rizzo E, Duchosal MA, Duran R, Goncalves-Matoso V, Schnyder P, et al. Radiological profile of anemia on unenhanced MDCT of the thorax. Eur Radiol. 2008;18(9):1863-8.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e Zopfs D, Rinneburger M, Pinto Dos Santos D, Reimer RP, Laukamp KR, Maintz D, et al. Evaluating anemia using contrast-enhanced spectral detector CT of the chest in a large cohort of 522 patients. Eur Radiol. 2021;31(6):4350-7.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e Title RS, Harper K, Nelson E, Evans T, Tello R. Observer performance in assessing anemia on thoracic CT. American Journal of Roentgenology. 2005;185(5):1240-4.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e Corcoran HL, Cook DE, Proto AV. Diagnosis of anemia on computed tomography scans of the thorax. Journal of Computed Tomography. 1988;12(2):116\u0026thinsp;\u0026minus;\u0026thinsp;21.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e Zhang J, Wu M, Huang J, Li S, Ye Z. Comparison between thoracic low-dose computed tomography and conventional-dose computed tomography in evaluating anemia: A preliminary study in a Chinese screening cohort. Frontiers in Cardiovascular Medicine. 2022;9:987753.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003e Desaint P, Bernard C, Contou D. Diagnosing anemia with chest CT-scan: the aortic ring sign. The American Journal of the Medical Sciences. 2022;363(2):e17.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Anemia, Chest CT scan, CT diagnosis, Infant, Children","lastPublishedDoi":"10.21203/rs.3.rs-7508114/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7508114/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e\u003cp\u003eThe present study aimed to evaluate the diagnostic accuracy of subjective and objective criteria for diagnosing anemia on an unenhanced thoracic CT scan in infants and children.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eA total of 281 subjects were included in the study. The prevalence of mild, moderate, and severe anemia in the participants was 34 (12.1%), 126 (44.8%), and 14 (5%) individuals, respectively. Additionally, 104 (37%) cases represented the aortic rim sign, and 79 (28.1%) represented the interventricular septum sign. The interventricular septum sign presented 35.05% of sensitivity and 83% specificity, while the aortic rim sign indicated 41.37% and 69.81% of sensitivity and specificity, respectively.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e\u003cp\u003eIt is possible to detect anemia from an unenhanced chest CT scan. Both objective and subjective criteria show values of sensitivity and specificity; however, in some cases, it would not be reliable. Additionally, a chest CT scan would be more accurate in detecting severe anemia.\u003c/p\u003e","manuscriptTitle":"Detecting Anemia in Pediatrics by unenhanced thoracic Computed Tomography Scan","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-09-17 04:58:54","doi":"10.21203/rs.3.rs-7508114/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"cc0709dc-45f4-47a1-bbac-526ad15e3c3c","owner":[],"postedDate":"September 17th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-12-02T04:39:23+00:00","versionOfRecord":[],"versionCreatedAt":"2025-09-17 04:58:54","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7508114","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7508114","identity":"rs-7508114","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}