Dose Reference Level for Paediatric Computed Tomography Examinations at a Private Diagnostic Centre, Benin City

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This study analyzed 608 pediatric CT examinations, revealing significant variations in demographic characteristics, machine parameters, and radiation exposure. Key findings indicated a predominance of male participants (60.2%), with head and brain scans comprising 89% of examinations. Contrast-enhanced studies demonstrated substantially higher radiation doses, with mean Computed Tomography Dose Index (CTDI) of 45.08 ± 21.53 mGy compared to 22.95 ± 8.45 mGy for non-contrast procedures. Machine parameters showed considerable variability, with kilovoltage ranging from 80–125 and milliamperage from 50–450. Head and brain scans exhibited the highest radiation exposure (CTDI 52.26 mGy, DLP 1182.24 mGy·cm), while chest examinations reported the lowest (CTDI 13.95 mGy, DLP 238.30 mGy·cm). The study underscores the critical need for age-specific and weight-based CT protocol optimization, careful contrast medium usage, and continuous radiation exposure monitoring in pediatric imaging. These findings contribute to the ongoing global effort to minimize radiation risks while maintaining diagnostic image quality Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction The increasing use of computed tomography (CT) imaging in paediatric care has sparked growing concerns about the potential risks associated with radiation exposure. CT scans, while immensely valuable for diagnosing a wide range of medical conditions, expose patients to ionizing radiation, which can be harmful, particularly for children. Paediatric patients are at a higher risk of radiation-induced harm due to their increased sensitivity to radiation, rapid cellular division rates, and longer life expectancy, which provides more time for radiation-induced malignancies to develop (Rehani & Frush, 2018 ). According to Huang et al., 2020 children are three to five times more sensitive to radiation than adults, which increases their risk of developing radiation-induced cancers later in life. Globally, concerns have been raised over the growing reliance on CT imaging in paediatric healthcare, especially as studies indicate that many CT examinations are performed without appropriate dose optimization for younger patients (Abdulkadir et al., 2020 ). In some cases, adult protocols are used for paediatric patients, leading to significantly higher radiation doses than necessary. Moreover, CT scans are increasingly being used in emergency settings and routine diagnostics, contributing to the rise in cumulative radiation exposure among children (Lin et al., 2023 ). The establishment of diagnostic reference levels (DRLs) has been one of the major international responses to concerns over radiation exposure. DRLs serve as a benchmark for controlling and optimizing the radiation dose administered during diagnostic imaging procedures. However, despite international efforts to regulate and minimize radiation exposure through DRLs, several studies have shown that paediatric patients continue to receive doses higher than the recommended limits, particularly in developing countries where dose optimization and awareness are often lacking (Harbron et al., 2020 ). For example, studies conducted in European countries have shown significant variation in paediatric CT doses, with many centers exceeding the European DRLs (Vassileva & Rehani, 2015 ). In Nigeria, paediatric CT imaging is widely used, but there is limited research and data available on the radiation doses administered to children during these procedures. Most diagnostic centers in Nigeria, including Raytouch Diagnostic Center in Benin City, perform paediatric CT examinations as part of routine clinical practice, yet the level of awareness and adherence to international DRLs remains unclear. A study conducted by Inko-Tariah et al. ( 2019 ) revealed that many facilities in Nigeria lack the necessary protocols and technologies to optimize radiation doses for paediatric patients. This raises significant concerns about the long-term health risks for children undergoing CT scans, as repeated exposure to high doses of radiation may increase the incidence of radiation-induced diseases in the future. Furthermore, while international bodies such as the International Atomic Energy Agency (IAEA) and the American College of Radiology (ACR) have provided guidelines for radiation dose optimization, these standards have not been widely implemented across low- and middle-income countries (Harbron et al., 2020 ). The use of CT imaging for paediatric patients has increased significantly due to its ability to provide detailed cross-sectional images that are crucial for diagnosis. However, the high radiation doses associated with CT imaging raise concerns about the long-term effects of radiation exposure, particularly in paediatric patients who are more vulnerable to its adverse effects (Gazzaz, 2020). In diagnostic centers worldwide, the challenge is to balance the diagnostic benefits of CT against the risks posed by radiation. Evidence suggests that paediatric patients are sometimes subjected to radiation doses that exceed international diagnostic reference levels (DRLs) due to factors such as the application of adult imaging protocols and lack of dose optimization (Muhammad et al., 2021 ) Without adequate evaluation, there is a risk that paediatric patients at Raytouch Diagnostic Center could be receiving unnecessarily high doses of radiation, thus increasing their risk of long-term radiation-induced conditions. This study will address this gap by assessing the types of paediatric CT examinations performed and evaluating the radiation doses administered. In Nigeria, regulatory frameworks governing radiation use in medical imaging are still evolving, and there is a need for diagnostic centers to align with global best practices. This study, therefore, aims to evaluate the types of paediatric CT examinations conducted at Raytouch Diagnostic Center, assess the radiation doses administered to paediatric patients, and compare these doses with internationally accepted DRLs. The findings will contribute to the growing body of knowledge on radiation protection and optimization in paediatric imaging in Nigeria. Methodology Research Setting The study was conducted at Raytouch Diagnostic Center, Benin City, a healthcare facility that provides various diagnostic services, including CT scans. The center is equipped with modern CT equipment, making it an ideal location for evaluating paediatric radiation doses. Study Design A retrospective study design was employed to evaluate radiation doses administered to paediatric patients during CT examinations. Data was collected data from September 2020 to September 2024. Target Population The target population for this study included all paediatric patients aged 0–17 years who underwent CT examinations at Raytouch Diagnostic Center during the study period. Paediatric patients were categorized based on age groups: 0–1 year (infants), 2–5 years (toddlers), 6–12 years (children), and 13–17 years (adolescents) (Rehani & Frush, 2018 ). Sampling Technique and Sample Size A purposive sampling technique was used to select paediatric patients who met the inclusion criteria. The sample size was determined based on the number of paediatric CT procedures conducted during the study period. The inclusion criteria consist of paediatric patients who have undergone CT scans and have complete data on the radiation dose received. Instrument for Data Collection Data on radiation dose levels was collected from the dose reports generated by the CT scanner. The primary parameters collected include Computed Tomography Dose Index (CTDI), dose length product (DLP) and effective dose (mSv) (Gazzaz, 2020). Additional patient data, such as age, sex, body weight, and the type of CT examination, was also be recorded. Validity of the Instrument The CT dose reports generated by the CT scanner are standardized and validated as per the manufacturer’s specifications, ensuring accurate and reliable dose measurements (Rehani & Frush, 2018 ). Reliability of the Instrument Reliability of the dose measurement data will be ensured through consistent calibration of the CT scanner and adherence to established protocols for CT dose recording. Repeatability of dose measurements will be checked by comparing values from similar CT examinations over a given period. Method of Data Collection Data was collected by reviewing the CT dose reports of paediatric patients who have undergone CT scans at Raytouch Diagnostic Center. The collected data include the type of CT scan, patient demographic information (age, sex, weight), and the corresponding radiation dose parameters (CTDI, DLP and effective dose) (Gazzaz, 2020). The data collection process was carried out over a period of five years. Method of Data Analysis Data analysis was performed using descriptive statistics to summarize the radiation dose levels for each type of paediatric CT examination. The mean, median, and standard deviation of the radiation dose (CTDI, DLP and effective dose) was calculated. The doses were compared to internationally established diagnostic reference levels (DRLs) for paediatric CT examinations. Inferential statistics was used to identify significant factors influencing dose variations, using regression analysis and Analysis of Variance (ANOVA) was used for comparison test. The statistical analysis was performed using IBM Statistical Package for Social Sciences (SPSS) version 28.0 for windows. The level of significance was set at p < 0.05. Ethical Considerations The study adhered to ethical guidelines for research involving human subjects. A letter of introduction was collected from the Department of Radiography and Ethical approval was obtained from the University of Benin Teaching Hospital (UBTH) Ethics committee. I proceeded to the diagnostic centre to obtained research ethical approval to conduct the study and since the study was retrospective, it didn’t need patient’s informed consent either from the parents or guardians of the paediatric patients before data collection. Confidentiality of patient data was ensured throughout the study. Results Table 4.1 Demographic and exposure parameters Frequency Percentage Sex Male 366 60.2 Female 242 39.8 Contrast used Yes 425 69.9 No 183 30.1 Type of CT examination Abdomen 58 9.5 Chest 9 1.5 Head/Brain 541 89.0 Age group (Years) 5 548 90.1 Table 4.1 shows the demographic Characteristics. The study encompassed 608 participants, with a significant gender disparity. Male participants dominated the sample, representing 366 individuals (60.2%), while females accounted for 242 participants (39.8%). Contrast medium usage was prevalent, with 425 examinations (69.9%) employing contrast, compared to 183 examinations (30.1%) without contrast. The distribution of CT examination types was notably uneven. Head and brain scans overwhelmingly comprised the majority, representing 541 examinations (89.0%). Abdominal examinations were less frequent, accounting for 58 cases (9.5%), while chest examinations were minimal at just 9 procedures (1.5%). Age group distribution revealed a substantial skew, with 548 participants (90.1%) over 5 years old and only 60 individuals (9.9%) under 5 years of age. Table 4.2 Descriptive statistics of machine parameters N Minimum Maximum Mean Std. Deviation kVp 608 80 125 119.50 5.19 mA 608 50 450 143.13 78.76 Pitch 608 .53 1.68 0.68 0.25 Slice thickness (mm) 608 1.25 5.00 3.16 1.79 Rotation time(sec) 608 .50 1.50 1.15 0.28 Table 4.2 shows the descriptive statistics of machine parameters. The descriptive statistics of machine parameters demonstrated considerable variability across 608 examinations. Kilovoltage (kVp) ranged from 80 to 125, with a mean of 119.50 and a standard deviation of 5.19. Milliamperage (mA) showed more pronounced variation, spanning from 50 to 450, with a mean of 143.13 and a standard deviation of 78.76. Pitch values varied between 0.53 and 1.68, averaging 0.68 with a standard deviation of 0.25. Slice thickness ranged from 1.25 to 5.00 millimeters, with a mean of 3.16 millimeters and a standard deviation of 1.79. Rotation time remained relatively consistent, ranging from 0.50 to 1.50 seconds, with a mean of 1.15 seconds and a standard deviation of 0.28. Table 4.3 Mean and Standard Deviation of CTDI and DLP Based on Contrast Use Contrast Used CTDI (Mean ± SD) DLP (Mean ± SD) Yes 45.08 ± 21.53 979.85 ± 447.76 No 22.95 ± 8.45 518.59 ± 239.75 Total 38.41 ± 21.17 841.02 ± 449.57 Table 4.3 shows the mean Dose Measurements by Contrast Use. Examinations with contrast medium showed significantly higher radiation exposure. The mean Computed Tomography Dose Index (CTDI) was 45.08 ± 21.53 mGy, with mean Dose-Length Product (DLP) was 979.85 ± 447.76 mGy·cm. Non-contrast procedures demonstrated lower radiation exposure, with a mean CTDI of 22.95 ± 8.45 mGy. The mean DLP for non-contrast examinations was 518.59 ± 239.75 mGy·cm. Table 4.4 Mean and Standard Deviation of CTDI and DLP by Type of CT Examination Type of CT Examination CTDI (Mean ± SD) DLP (Mean ± SD) Abdomen 38.12 ± 29.61 802.97 ± 321.07 Chest 13.95 ± 0.00 238.30 ± 0.00 Head/Brain 38.85 ± 20.03 855.12 ± 458.15 Total 38.41 ± 21.17 841.02 ± 449.57 Table 4.4 shows the Dose Measurements by Contrast Use (Table 4.3 and Table 4.5 ) Examinations with contrast medium showed significantly higher radiation exposure. The mean Computed Tomography Dose Index (CTDI) was 45.08 ± 21.53 mGy, with a dose reference level of 57.49 mGy. The mean Dose-Length Product (DLP) was 979.85 ± 447.76 mGy·cm, with a dose reference level of 1346.33 mGy·cm. Non-contrast procedures demonstrated lower radiation exposure, with a mean CTDI of 22.95 ± 8.45 mGy and a dose reference level of 26.04 mGy. The mean DLP for non-contrast examinations was 518.59 ± 239.75 mGy·cm, with a dose reference level of 664.55 mGy·cm. Table 4.5 Dose Reference Levels by Contrast Use Contrast Used CTDI (mGy) DLP (mGy·cm) Yes 57.49 1346.33 No 26.04 664.55 Table 4.5 shows the Dose Measurements by Contrast Use. Examinations with contrast medium showed significantly higher radiation exposure. For contrast use participants, the mean CTDI dose reference level of 57.49 mGy, with a DLP dose reference level of 1346.33 mGy·cm. Non-contrast procedures demonstrated lower radiation exposure, with a mean CTDI dose reference level of 26.04 mGy, with a DLP dose reference level of 664.55 mGy·cm. Table 4.6 Dose Reference Levels by Type of CT Examination Type of CT Examination CTDI (mGy) DLP (mGy·cm) Abdomen 43.24 1104.14 Chest 13.95 238.30 Head/Brain 52.26 1182.24 Table 4.6 shows the dose Reference Levels by Type of CT Examination. Head and brain scans exhibited high radiation exposure, with a mean CTDI dose reference level of 52.26 mGy, while the mean DLP was with a dose reference level of 1182.24 mGy·cm. Abdominal examinations showed a mean CTDI dose reference level of 43.24 mGy with a mean DLP dose reference level of 1104.14 mGy·cm. Chest examinations reported the lowest radiation exposure, with a mean dose reference level of 13.95 mGy for CTDI and 238.30 mGy·cm for DLP. Discussion of findings The study’s sample of 608 participants demonstrates notable demographic variations that correspond with and differ from current paediatric CT literature. The gender distribution (60.2% male, 39.8% female) is significantly imbalanced, aligning with the observations of Alkhorayef ( 2020 ), who noted comparable gender disparities in paediatric CT populations in Saudi Arabia. The distribution of examination types is notably pronounced, with head and brain scans comprising 89.0% (541 examinations). This exceptionally elevated percentage of neurological imaging closely corresponds with many worldwide researches. Benmessaoud et al. ( 2020 ) conducted a state-wide survey in Morocco and similarly identified head CT as the predominant paediatric examination type, underscoring a global trend in paediatric neuroimaging. The age group distribution is significant, with 90.1% of individuals over 5 years of age. This age stratification aligns with the findings of Muhammad et al. ( 2020 ), who classified paediatric patients into age groups and observed comparable biases towards older children. Almén et al. ( 2022 ) highlighted the significance of age-based categorization, observing considerable disparities in radiation exposure among different age groups. The machine parameter study reveals intricate technical variances that have major significance for paediatric imaging. The kilovoltage (kVp) range of 80–125, with a mean of 119.50, indicates the technological difficulty of paediatric CT protocols. Aboul Hamad et al. ( 2023 ) emphasized the importance of tube voltage, demonstrating that minor fluctuations can considerably affect radiation dose in cardiac CT scans. The milliamperage (mA) demonstrated remarkable variability, ranging from 50 to 450 with a standard deviation of 78.76. This large range coincides with Satharasinghe et al. ( 2021 ), who emphasized the methodological discrepancies in paediatric CT dose measurements across worldwide studies. The vast variety suggests major modifications in contemporary settings to accommodate diverse paediatric imaging requirements. The radiation exposure data are particularly strong. Contrast-enhanced tests indicated considerably greater radiation levels, with a mean CTDI of 45.08 ± 21.53 mGy compared to 22.95 ± 8.45 mGy for non-contrast procedures. These findings largely coincide with Satharasinghe et al. ( 2022 ), who developed national diagnostic reference levels (NDRL) for pediatric CT examinations. The feasible dose ranges they identified were very similar: head areas at 45.8–57.2 mGy, with chest and belly displaying lower values. The contrast medium influence is extremely important. Dose reference values with contrast (CTDI 57.49 mGy, DLP 1346.33 mGy·cm) considerably exceed non-contrast procedures (CTDI 26.04 mGy, DLP 664.55 mGy·cm). This huge disparity reflects Alqahtani et al. ( 2023 ), who observed considerable variability in radiation dose across different imaging procedures. Conclusion In this study on dose reference values for paediatric CT scans at Raytouch Diagnostic Center, Benin City, some crucial findings emerged regarding radiation exposure and imaging techniques. The study indicated considerable demographic disparities, with a majority of male patients and a higher frequency of examinations among children over five years old. Additionally, radiation exposure patterns suggested that contrast-enhanced scans consistently resulted in greater doses, underlining the significance of careful consideration when employing contrast media in paediatric imaging. Further, the study identified disparities in radiation exposure across various examination types, with head and brain CT scans demonstrating significantly greater doses compared to chest and abdomen scans. This conclusion underscores the need for specific imaging procedures adapted to diverse anatomical locations. Moreover, large variability in machine parameters, including kilovoltage, milliamperage, and slice thickness, provide potential for standardization and optimization to promote radiation safety while retaining diagnostic quality. Overall, our findings underline the significance of modifying paediatric CT techniques to limit radiation exposure without compromising image quality. Establishing dose reference levels and adjusting scanning parameters will lead to safer imaging techniques and enhanced patient care in paediatric radiology. Declarations Author Contribution (OGE): Conceptualization, Study Design, Data Collection, Data Analysis, Drafting of Manuscript, and Final Approval of the Version to be Published.(EEE): Literature Review, Data Collection, Data Interpretation, Manuscript Review and Editing, and Approval of Final Manuscript. Data Availability Data is provided on request from the corresponding author References Abdulkadir, M. K., Rahim, N. A. Y. M., Mazlan, N. S., Daud, N. M., Shuaib, I. L., & Osman, N. D. (2020). Dose optimisation in paediatric CT examination: Assessment on current scanning protocols associated with radiation dose. Radiation Physics and Chemistry , 171 , 108740. Aboul Hamad, M. S., Attalla, E. M., Amer, H. H., & Fathy, M. M. (2023). Impact of tube voltage on diagnostic reference levels for paediatric cardiac computed tomography. 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Journal of Radiological Protection, 38(3), 1013. Yang, F., & Gao, L. (2024). Age-based diagnostic reference levels and achievable doses for paediatric CT: a survey in Shanghai, China. Zalokar, N., Žager Marciuš, V., & Mekiš, N. (2020). Establishment of national diagnostic reference levels for radiotherapy computed tomography simulation procedures in Slovenia. European Journal of Radiology, 127, 108979. 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-6805307","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":465962933,"identity":"cd76091d-fcd4-4cf8-a409-bb8989782e35","order_by":0,"name":"Enosakhare Okungbowa","email":"data:image/png;base64,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","orcid":"","institution":"University of Benin","correspondingAuthor":true,"prefix":"","firstName":"Enosakhare","middleName":"","lastName":"Okungbowa","suffix":""},{"id":465962934,"identity":"54518f80-8539-4068-9acf-db4002449281","order_by":1,"name":"Evwomazino Erezi-Kesi","email":"","orcid":"","institution":"University of Benin","correspondingAuthor":false,"prefix":"","firstName":"Evwomazino","middleName":"","lastName":"Erezi-Kesi","suffix":""}],"badges":[],"createdAt":"2025-06-02 21:38:19","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6805307/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6805307/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":83917239,"identity":"7f2b1b75-4b41-4342-ba07-0b63ca10e4b7","added_by":"auto","created_at":"2025-06-04 12:55:40","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":8129,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eComparison of CTDI based on contrast used\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"image1.png","url":"https://assets-eu.researchsquare.com/files/rs-6805307/v1/57efc33b141d51f2b24c6da9.png"},{"id":83916362,"identity":"c05b75af-036c-47ce-8fb9-8711aac4fe1e","added_by":"auto","created_at":"2025-06-04 12:47:40","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":8157,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eComparison of DLP based on contrast used\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"image2.png","url":"https://assets-eu.researchsquare.com/files/rs-6805307/v1/36fdbe733e9d4eeb6cba1c05.png"},{"id":83916367,"identity":"59ed82d8-fe51-45d1-ad68-e458656f6858","added_by":"auto","created_at":"2025-06-04 12:47:40","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":9475,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eComparison of CTDI for different examinations\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"image3.png","url":"https://assets-eu.researchsquare.com/files/rs-6805307/v1/f4ebcf128ff0ddb0f8625068.png"},{"id":83917238,"identity":"2470de77-2356-40a8-92c9-a7b4d1c7370f","added_by":"auto","created_at":"2025-06-04 12:55:40","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":9538,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eComparison of DLP for different examinations\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"image4.png","url":"https://assets-eu.researchsquare.com/files/rs-6805307/v1/0fc7b50eb5ef7673a7550f9c.png"},{"id":85089595,"identity":"b1f76608-a30f-43fb-8ee2-e73e41cbb9ab","added_by":"auto","created_at":"2025-06-20 22:16:26","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":759297,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6805307/v1/c74732e8-455e-453f-b63d-74b3ac7953a0.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eDose Reference Level for Paediatric Computed Tomography Examinations at a Private Diagnostic Centre, Benin City\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003eThe increasing use of computed tomography (CT) imaging in paediatric care has sparked growing concerns about the potential risks associated with radiation exposure. CT scans, while immensely valuable for diagnosing a wide range of medical conditions, expose patients to ionizing radiation, which can be harmful, particularly for children. Paediatric patients are at a higher risk of radiation-induced harm due to their increased sensitivity to radiation, rapid cellular division rates, and longer life expectancy, which provides more time for radiation-induced malignancies to develop (Rehani \u0026amp; Frush, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). According to Huang et al., \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2020\u003c/span\u003e children are three to five times more sensitive to radiation than adults, which increases their risk of developing radiation-induced cancers later in life.\u003c/p\u003e \u003cp\u003eGlobally, concerns have been raised over the growing reliance on CT imaging in paediatric healthcare, especially as studies indicate that many CT examinations are performed without appropriate dose optimization for younger patients (Abdulkadir et al., \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). In some cases, adult protocols are used for paediatric patients, leading to significantly higher radiation doses than necessary. Moreover, CT scans are increasingly being used in emergency settings and routine diagnostics, contributing to the rise in cumulative radiation exposure among children (Lin et al., \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2023\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe establishment of diagnostic reference levels (DRLs) has been one of the major international responses to concerns over radiation exposure. DRLs serve as a benchmark for controlling and optimizing the radiation dose administered during diagnostic imaging procedures. However, despite international efforts to regulate and minimize radiation exposure through DRLs, several studies have shown that paediatric patients continue to receive doses higher than the recommended limits, particularly in developing countries where dose optimization and awareness are often lacking (Harbron et al., \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). For example, studies conducted in European countries have shown significant variation in paediatric CT doses, with many centers exceeding the European DRLs (Vassileva \u0026amp; Rehani, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2015\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eIn Nigeria, paediatric CT imaging is widely used, but there is limited research and data available on the radiation doses administered to children during these procedures. Most diagnostic centers in Nigeria, including Raytouch Diagnostic Center in Benin City, perform paediatric CT examinations as part of routine clinical practice, yet the level of awareness and adherence to international DRLs remains unclear. A study conducted by Inko-Tariah et al. (\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2019\u003c/span\u003e) revealed that many facilities in Nigeria lack the necessary protocols and technologies to optimize radiation doses for paediatric patients. This raises significant concerns about the long-term health risks for children undergoing CT scans, as repeated exposure to high doses of radiation may increase the incidence of radiation-induced diseases in the future.\u003c/p\u003e \u003cp\u003eFurthermore, while international bodies such as the International Atomic Energy Agency (IAEA) and the American College of Radiology (ACR) have provided guidelines for radiation dose optimization, these standards have not been widely implemented across low- and middle-income countries (Harbron et al., \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2020\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe use of CT imaging for paediatric patients has increased significantly due to its ability to provide detailed cross-sectional images that are crucial for diagnosis. However, the high radiation doses associated with CT imaging raise concerns about the long-term effects of radiation exposure, particularly in paediatric patients who are more vulnerable to its adverse effects (Gazzaz, 2020).\u003c/p\u003e \u003cp\u003eIn diagnostic centers worldwide, the challenge is to balance the diagnostic benefits of CT against the risks posed by radiation. Evidence suggests that paediatric patients are sometimes subjected to radiation doses that exceed international diagnostic reference levels (DRLs) due to factors such as the application of adult imaging protocols and lack of dose optimization (Muhammad et al., \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2021\u003c/span\u003e) Without adequate evaluation, there is a risk that paediatric patients at Raytouch Diagnostic Center could be receiving unnecessarily high doses of radiation, thus increasing their risk of long-term radiation-induced conditions. This study will address this gap by assessing the types of paediatric CT examinations performed and evaluating the radiation doses administered.\u003c/p\u003e \u003cp\u003eIn Nigeria, regulatory frameworks governing radiation use in medical imaging are still evolving, and there is a need for diagnostic centers to align with global best practices. This study, therefore, aims to evaluate the types of paediatric CT examinations conducted at Raytouch Diagnostic Center, assess the radiation doses administered to paediatric patients, and compare these doses with internationally accepted DRLs. The findings will contribute to the growing body of knowledge on radiation protection and optimization in paediatric imaging in Nigeria.\u003c/p\u003e"},{"header":"Methodology","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eResearch Setting\u003c/h2\u003e \u003cp\u003eThe study was conducted at Raytouch Diagnostic Center, Benin City, a healthcare facility that provides various diagnostic services, including CT scans. The center is equipped with modern CT equipment, making it an ideal location for evaluating paediatric radiation doses.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eStudy Design\u003c/h3\u003e\n\u003cp\u003eA retrospective study design was employed to evaluate radiation doses administered to paediatric patients during CT examinations. Data was collected data from September 2020 to September 2024.\u003c/p\u003e\n\u003ch3\u003eTarget Population\u003c/h3\u003e\n\u003cp\u003eThe target population for this study included all paediatric patients aged 0\u0026ndash;17 years who underwent CT examinations at Raytouch Diagnostic Center during the study period. Paediatric patients were categorized based on age groups: 0\u0026ndash;1 year (infants), 2\u0026ndash;5 years (toddlers), 6\u0026ndash;12 years (children), and 13\u0026ndash;17 years (adolescents) (Rehani \u0026amp; Frush, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2018\u003c/span\u003e).\u003c/p\u003e\n\u003ch3\u003eSampling Technique and Sample Size\u003c/h3\u003e\n\u003cp\u003eA purposive sampling technique was used to select paediatric patients who met the inclusion criteria. The sample size was determined based on the number of paediatric CT procedures conducted during the study period. The inclusion criteria consist of paediatric patients who have undergone CT scans and have complete data on the radiation dose received.\u003c/p\u003e\n\u003ch3\u003eInstrument for Data Collection\u003c/h3\u003e\n\u003cp\u003eData on radiation dose levels was collected from the dose reports generated by the CT scanner. The primary parameters collected include Computed Tomography Dose Index (CTDI), dose length product (DLP) and effective dose (mSv) (Gazzaz, 2020). Additional patient data, such as age, sex, body weight, and the type of CT examination, was also be recorded.\u003c/p\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eValidity of the Instrument\u003c/h2\u003e \u003cp\u003eThe CT dose reports generated by the CT scanner are standardized and validated as per the manufacturer\u0026rsquo;s specifications, ensuring accurate and reliable dose measurements (Rehani \u0026amp; Frush, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2018\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eReliability of the Instrument\u003c/h3\u003e\n\u003cp\u003eReliability of the dose measurement data will be ensured through consistent calibration of the CT scanner and adherence to established protocols for CT dose recording. Repeatability of dose measurements will be checked by comparing values from similar CT examinations over a given period.\u003c/p\u003e\n\u003ch3\u003eMethod of Data Collection\u003c/h3\u003e\n\u003cp\u003eData was collected by reviewing the CT dose reports of paediatric patients who have undergone CT scans at Raytouch Diagnostic Center. The collected data include the type of CT scan, patient demographic information (age, sex, weight), and the corresponding radiation dose parameters (CTDI, DLP and effective dose) (Gazzaz, 2020). The data collection process was carried out over a period of five years.\u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eMethod of Data Analysis\u003c/h2\u003e \u003cp\u003eData analysis was performed using descriptive statistics to summarize the radiation dose levels for each type of paediatric CT examination. The mean, median, and standard deviation of the radiation dose (CTDI, DLP and effective dose) was calculated. The doses were compared to internationally established diagnostic reference levels (DRLs) for paediatric CT examinations. Inferential statistics was used to identify significant factors influencing dose variations, using regression analysis and Analysis of Variance (ANOVA) was used for comparison test. The statistical analysis was performed using IBM Statistical Package for Social Sciences (SPSS) version 28.0 for windows. The level of significance was set at p\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eEthical Considerations\u003c/h2\u003e \u003cp\u003e The study adhered to ethical guidelines for research involving human subjects. A letter of introduction was collected from the Department of Radiography and Ethical approval was obtained from the University of Benin Teaching Hospital (UBTH) Ethics committee. I proceeded to the diagnostic centre to obtained research ethical approval to conduct the study and since the study was retrospective, it didn\u0026rsquo;t need patient\u0026rsquo;s informed consent either from the parents or guardians of the paediatric patients before data collection. Confidentiality of patient data was ensured throughout the study.\u003c/p\u003e \u003c/div\u003e "},{"header":"Results","content":"\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4.1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eDemographic and exposure parameters\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eFrequency\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003ePercentage\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\u003eSex\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eMale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e366\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e60.2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFemale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e242\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e39.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eContrast used\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e425\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e69.9\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e183\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e30.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003eType of CT examination\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAbdomen\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e58\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e9.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eChest\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e1.5\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHead/Brain\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e541\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e89.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eAge group (Years)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e9.9\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u0026gt;\u0026thinsp;5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e548\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e90.1\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\u003eTable\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e4.1\u003c/span\u003e shows the demographic Characteristics. The study encompassed 608 participants, with a significant gender disparity. Male participants dominated the sample, representing 366 individuals (60.2%), while females accounted for 242 participants (39.8%). Contrast medium usage was prevalent, with 425 examinations (69.9%) employing contrast, compared to 183 examinations (30.1%) without contrast. The distribution of CT examination types was notably uneven. Head and brain scans overwhelmingly comprised the majority, representing 541 examinations (89.0%). Abdominal examinations were less frequent, accounting for 58 cases (9.5%), while chest examinations were minimal at just 9 procedures (1.5%). Age group distribution revealed a substantial skew, with 548 participants (90.1%) over 5 years old and only 60 individuals (9.9%) under 5 years of age.\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 4.2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eDescriptive statistics of machine parameters\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"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=\"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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMinimum\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMaximum\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eMean\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eStd. Deviation\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ekVp\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e608\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e80\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e125\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e119.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e5.19\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003emA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e608\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e450\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e143.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e78.76\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePitch\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e608\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e.53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.68\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\u003e0.25\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSlice thickness (mm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e608\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e3.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e1.79\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRotation time(sec)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e608\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e1.15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e \u003cp\u003e0.28\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\u003eTable\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e4.2\u003c/span\u003e shows the descriptive statistics of machine parameters. The descriptive statistics of machine parameters demonstrated considerable variability across 608 examinations. Kilovoltage (kVp) ranged from 80 to 125, with a mean of 119.50 and a standard deviation of 5.19. Milliamperage (mA) showed more pronounced variation, spanning from 50 to 450, with a mean of 143.13 and a standard deviation of 78.76. Pitch values varied between 0.53 and 1.68, averaging 0.68 with a standard deviation of 0.25. Slice thickness ranged from 1.25 to 5.00 millimeters, with a mean of 3.16 millimeters and a standard deviation of 1.79. Rotation time remained relatively consistent, ranging from 0.50 to 1.50 seconds, with a mean of 1.15 seconds and a standard deviation of 0.28.\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 4.3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eMean and Standard Deviation of CTDI and DLP Based on Contrast Use\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=\"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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eContrast Used\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCTDI (Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eDLP (Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e45.08\u0026thinsp;\u0026plusmn;\u0026thinsp;21.53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e979.85\u0026thinsp;\u0026plusmn;\u0026thinsp;447.76\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e22.95\u0026thinsp;\u0026plusmn;\u0026thinsp;8.45\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e518.59\u0026thinsp;\u0026plusmn;\u0026thinsp;239.75\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eTotal\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e38.41\u0026thinsp;\u0026plusmn;\u0026thinsp;21.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e841.02\u0026thinsp;\u0026plusmn;\u0026thinsp;449.57\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\u003eTable\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e4.3\u003c/span\u003e shows the mean Dose Measurements by Contrast Use. Examinations with contrast medium showed significantly higher radiation exposure. The mean Computed Tomography Dose Index (CTDI) was 45.08\u0026thinsp;\u0026plusmn;\u0026thinsp;21.53 mGy, with mean Dose-Length Product (DLP) was 979.85\u0026thinsp;\u0026plusmn;\u0026thinsp;447.76 mGy\u0026middot;cm. Non-contrast procedures demonstrated lower radiation exposure, with a mean CTDI of 22.95\u0026thinsp;\u0026plusmn;\u0026thinsp;8.45 mGy. The mean DLP for non-contrast examinations was 518.59\u0026thinsp;\u0026plusmn;\u0026thinsp;239.75 mGy\u0026middot;cm.\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 4.4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eMean and Standard Deviation of CTDI and DLP by Type of CT Examination\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=\"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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eType of CT Examination\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCTDI (Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eDLP (Mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAbdomen\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e38.12\u0026thinsp;\u0026plusmn;\u0026thinsp;29.61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e802.97\u0026thinsp;\u0026plusmn;\u0026thinsp;321.07\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChest\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e13.95\u0026thinsp;\u0026plusmn;\u0026thinsp;0.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e238.30\u0026thinsp;\u0026plusmn;\u0026thinsp;0.00\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHead/Brain\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e38.85\u0026thinsp;\u0026plusmn;\u0026thinsp;20.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e855.12\u0026thinsp;\u0026plusmn;\u0026thinsp;458.15\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eTotal\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e38.41\u0026thinsp;\u0026plusmn;\u0026thinsp;21.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c3\"\u003e \u003cp\u003e841.02\u0026thinsp;\u0026plusmn;\u0026thinsp;449.57\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\u003eTable\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4.4\u003c/span\u003e shows the Dose Measurements by Contrast Use (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e4.3\u003c/span\u003e and Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e4.5\u003c/span\u003e)\u003c/p\u003e \u003cp\u003eExaminations with contrast medium showed significantly higher radiation exposure. The mean Computed Tomography Dose Index (CTDI) was 45.08\u0026thinsp;\u0026plusmn;\u0026thinsp;21.53 mGy, with a dose reference level of 57.49 mGy. The mean Dose-Length Product (DLP) was 979.85\u0026thinsp;\u0026plusmn;\u0026thinsp;447.76 mGy\u0026middot;cm, with a dose reference level of 1346.33 mGy\u0026middot;cm.\u003c/p\u003e \u003cp\u003eNon-contrast procedures demonstrated lower radiation exposure, with a mean CTDI of 22.95\u0026thinsp;\u0026plusmn;\u0026thinsp;8.45 mGy and a dose reference level of 26.04 mGy. The mean DLP for non-contrast examinations was 518.59\u0026thinsp;\u0026plusmn;\u0026thinsp;239.75 mGy\u0026middot;cm, with a dose reference level of 664.55 mGy\u0026middot;cm.\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 4.5\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eDose Reference Levels by Contrast Use\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=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eContrast Used\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCTDI (mGy)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eDLP (mGy\u0026middot;cm)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eYes\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e57.49\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e1346.33\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e26.04\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e664.55\u003c/b\u003e\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\u003eTable\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e4.5\u003c/span\u003e shows the Dose Measurements by Contrast Use. Examinations with contrast medium showed significantly higher radiation exposure. For contrast use participants, the mean CTDI dose reference level of 57.49 mGy, with a DLP dose reference level of 1346.33 mGy\u0026middot;cm. Non-contrast procedures demonstrated lower radiation exposure, with a mean CTDI dose reference level of 26.04 mGy, with a DLP dose reference level of 664.55 mGy\u0026middot;cm.\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 4.6\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eDose Reference Levels by Type of CT Examination\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=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eType of CT Examination\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCTDI (mGy)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eDLP (mGy\u0026middot;cm)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAbdomen\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e43.24\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e1104.14\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChest\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e13.95\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e238.30\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHead/Brain\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e52.26\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e1182.24\u003c/b\u003e\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\u003eTable\u0026nbsp;\u003cspan refid=\"Tab6\" class=\"InternalRef\"\u003e4.6\u003c/span\u003e shows the dose Reference Levels by Type of CT Examination. Head and brain scans exhibited high radiation exposure, with a mean CTDI dose reference level of 52.26 mGy, while the mean DLP was with a dose reference level of 1182.24 mGy\u0026middot;cm. Abdominal examinations showed a mean CTDI dose reference level of 43.24 mGy with a mean DLP dose reference level of 1104.14 mGy\u0026middot;cm. Chest examinations reported the lowest radiation exposure, with a mean dose reference level of 13.95 mGy for CTDI and 238.30 mGy\u0026middot;cm for DLP.\u003c/p\u003e \u003c/div\u003e "},{"header":"Discussion of findings","content":"\u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003cp\u003e The study\u0026rsquo;s sample of 608 participants demonstrates notable demographic variations that correspond with and differ from current paediatric CT literature. The gender distribution (60.2% male, 39.8% female) is significantly imbalanced, aligning with the observations of Alkhorayef (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2020\u003c/span\u003e), who noted comparable gender disparities in paediatric CT populations in Saudi Arabia.\u003c/p\u003e \u003cp\u003eThe distribution of examination types is notably pronounced, with head and brain scans comprising 89.0% (541 examinations). This exceptionally elevated percentage of neurological imaging closely corresponds with many worldwide researches. Benmessaoud et al. (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2020\u003c/span\u003e) conducted a state-wide survey in Morocco and similarly identified head CT as the predominant paediatric examination type, underscoring a global trend in paediatric neuroimaging.\u003c/p\u003e \u003cp\u003eThe age group distribution is significant, with 90.1% of individuals over 5 years of age. This age stratification aligns with the findings of Muhammad et al. (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2020\u003c/span\u003e), who classified paediatric patients into age groups and observed comparable biases towards older children. Alm\u0026eacute;n et al. (\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2022\u003c/span\u003e) highlighted the significance of age-based categorization, observing considerable disparities in radiation exposure among different age groups.\u003c/p\u003e \u003cp\u003eThe machine parameter study reveals intricate technical variances that have major significance for paediatric imaging. The kilovoltage (kVp) range of 80\u0026ndash;125, with a mean of 119.50, indicates the technological difficulty of paediatric CT protocols. Aboul Hamad et al. (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2023\u003c/span\u003e) emphasized the importance of tube voltage, demonstrating that minor fluctuations can considerably affect radiation dose in cardiac CT scans.\u003c/p\u003e \u003cp\u003eThe milliamperage (mA) demonstrated remarkable variability, ranging from 50 to 450 with a standard deviation of 78.76. This large range coincides with Satharasinghe et al. (\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2021\u003c/span\u003e), who emphasized the methodological discrepancies in paediatric CT dose measurements across worldwide studies. The vast variety suggests major modifications in contemporary settings to accommodate diverse paediatric imaging requirements.\u003c/p\u003e \u003cp\u003eThe radiation exposure data are particularly strong. Contrast-enhanced tests indicated considerably greater radiation levels, with a mean CTDI of 45.08\u0026thinsp;\u0026plusmn;\u0026thinsp;21.53 mGy compared to 22.95\u0026thinsp;\u0026plusmn;\u0026thinsp;8.45 mGy for non-contrast procedures.\u003c/p\u003e \u003cp\u003eThese findings largely coincide with Satharasinghe et al. (\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2022\u003c/span\u003e), who developed national diagnostic reference levels (NDRL) for pediatric CT examinations. The feasible dose ranges they identified were very similar: head areas at 45.8\u0026ndash;57.2 mGy, with chest and belly displaying lower values. The contrast medium influence is extremely important. Dose reference values with contrast (CTDI 57.49 mGy, DLP 1346.33 mGy\u0026middot;cm) considerably exceed non-contrast procedures (CTDI 26.04 mGy, DLP 664.55 mGy\u0026middot;cm). This huge disparity reflects Alqahtani et al. (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2023\u003c/span\u003e), who observed considerable variability in radiation dose across different imaging procedures.\u003c/p\u003e \u003c/div\u003e "},{"header":"Conclusion","content":"\u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003cp\u003eIn this study on dose reference values for paediatric CT scans at Raytouch Diagnostic Center, Benin City, some crucial findings emerged regarding radiation exposure and imaging techniques. The study indicated considerable demographic disparities, with a majority of male patients and a higher frequency of examinations among children over five years old. Additionally, radiation exposure patterns suggested that contrast-enhanced scans consistently resulted in greater doses, underlining the significance of careful consideration when employing contrast media in paediatric imaging. Further, the study identified disparities in radiation exposure across various examination types, with head and brain CT scans demonstrating significantly greater doses compared to chest and abdomen scans. This conclusion underscores the need for specific imaging procedures adapted to diverse anatomical locations. Moreover, large variability in machine parameters, including kilovoltage, milliamperage, and slice thickness, provide potential for standardization and optimization to promote radiation safety while retaining diagnostic quality. Overall, our findings underline the significance of modifying paediatric CT techniques to limit radiation exposure without compromising image quality. Establishing dose reference levels and adjusting scanning parameters will lead to safer imaging techniques and enhanced patient care in paediatric radiology.\u003c/p\u003e \u003c/div\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003e(OGE): Conceptualization, Study Design, Data Collection, Data Analysis, Drafting of Manuscript, and Final Approval of the Version to be Published.(EEE): Literature Review, Data Collection, Data Interpretation, Manuscript Review and Editing, and Approval of Final Manuscript.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eData is provided on request from the corresponding author\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAbdulkadir, M. K., Rahim, N. A. Y. M., Mazlan, N. S., Daud, N. M., Shuaib, I. L., \u0026amp; Osman, N. D. (2020). Dose optimisation in paediatric CT examination: Assessment on current scanning protocols associated with radiation dose. \u003cem\u003eRadiation Physics and Chemistry\u003c/em\u003e, \u003cem\u003e171\u003c/em\u003e, 108740.\u003c/li\u003e\n\u003cli\u003eAboul Hamad, M. S., Attalla, E. M., Amer, H. H., \u0026amp; Fathy, M. M. (2023). Impact of tube voltage on diagnostic reference levels for paediatric cardiac computed tomography. Radiation and Environmental Biophysics, 62, 331-338.\u003c/li\u003e\n\u003cli\u003eAlhailiy, A., Alkhybari, E., Alghamdi, S., Fisal, N., Aldosari, S., \u0026amp; Albeshan, S. (2023). Reporting diagnostic reference levels for paediatric patients undergoing brain computed tomography. Tomography, 9(6), 2029-2038.\u003c/li\u003e\n\u003cli\u003eAlkhorayef, M. (2020). Survey of paediatric imaging exposure from computed tomography examinations. Radiation Physics and Chemistry, 167, 108261.\u003c/li\u003e\n\u003cli\u003eAlm\u0026eacute;n, A., Gu\u0026eth;j\u0026oacute;nsd\u0026oacute;ttir, J., Heimland, N., H\u0026oslash;jgaard, B., Waltenburg, H., \u0026amp; Widmark, A. (2021). Establishing paediatric diagnostic reference levels using reference curves \u0026ndash; A feasibility study including conventional and CT examinations. \u003cem\u003ePhysica Medica\u003c/em\u003e, 87, 65-72.\u003c/li\u003e\n\u003cli\u003eAlm\u0026eacute;n, A., Gu\u0026eth;j\u0026oacute;nsd\u0026oacute;ttir, J., Heimland, N., H\u0026oslash;jgaard, B., Waltenburg, H., \u0026amp; Widmark, A. (2022). Paediatric diagnostic reference levels for common radiological examinations using the European guidelines. \u003cem\u003eBritish Journal of Radiology\u003c/em\u003e, 95(1130), 20210700.\u003c/li\u003e\n\u003cli\u003eAlqahtani, S., Soliman, K., Alotaibi, S., Alnofaie, K., Alahmari, A., Alyahya, F., Albdullah, A., \u0026amp; Alharbi, R. (2023). Analysis of local diagnostic reference levels for paediatric patients undergoing 18F-FDG PET/CT imaging for oncology. \u003cem\u003eJournal of Applied Mathematics and Physics\u003c/em\u003e, 11, 2144-2155.\u003c/li\u003e\n\u003cli\u003eBenmessaoud, M., Dadouch, A., Talbi, M., Tahiri, M., \u0026amp; El-ouardi, Y. (2020). Diagnostic reference levels for paediatric head computed tomography in Morocco: A nationwide survey. \u003cem\u003eRadiation Protection Dosimetry\u003c/em\u003e, 191(4), 400-408.\u003c/li\u003e\n\u003cli\u003eDe Monte, F., Castaldi, B., Branchini, M., Bettinelli, A., Milanesi, O., Paiusco, M., \u0026amp; Roggio, A. (2020). Typical values for paediatric interventional cardiology catheterizations: A standardized approach towards diagnostic reference level establishment. \u003cem\u003ePhysica Medica\u003c/em\u003e, 76, 134-141.\u003c/li\u003e\n\u003cli\u003eEuropean Commission. (2018). \u003cem\u003eRadiation protection no. 185: European guidelines on diagnostic reference levels for paediatric imaging\u003c/em\u003e.\u003c/li\u003e\n\u003cli\u003eFrush, D. P., Donnelly, L. F., \u0026amp; Rosen, N. S. (2020). Computed tomography and radiation risks: What paediatric health care providers should know. \u003cem\u003ePaediatric s\u003c/em\u003e, 112(4), 951-957. https://doi.org/10.1542/peds.112.4.951\u003c/li\u003e\n\u003cli\u003eGagliardi, R. M., Traverso, R., \u0026amp; Bonanni, L. (2017). Paediatric CT: Analysis of radiation exposure and diagnostic performance. \u003cem\u003eJournal of Radiological Protection\u003c/em\u003e, 37(2), 258-268. https://doi.org/10.1088/1361-6498/aa5d1f\u003c/li\u003e\n\u003cli\u003eGricienė, B., \u0026amp; \u0026Scaron;iuk\u0026scaron;terytė, M. (2021). Local diagnostic reference levels for paediatric head CT procedures. \u003cem\u003eActa Medica Lituanica\u003c/em\u003e, 28(2), 253-261.\u003c/li\u003e\n\u003cli\u003eHall, E. J., \u0026amp; Brenner, D. J. (2012). Cancer risks from diagnostic radiology. \u003cem\u003eBritish Journal of Radiology\u003c/em\u003e, 85(1006), 1016-1023. https://doi.org/10.1259/bjr/36096733\u003c/li\u003e\n\u003cli\u003eHarbron, R. W., Chapple, C. L., O\u0026apos;Sullivan, J. J., \u0026amp; O\u0026apos;Doherty, M. J. (2020). Paediatric computed tomography radiation doses: International trends and implications for radiation protection. \u003cem\u003eRadiation Protection Dosimetry\u003c/em\u003e, 186(1), 28-36. https://doi.org/10.1093/rpd/ncz289\u003c/li\u003e\n\u003cli\u003eHart, D., \u0026amp; Hillier, M. C. (2020). \u003cem\u003eDiagnostic reference levels in medical imaging: Their use and impact\u003c/em\u003e.\u003c/li\u003e\n\u003cli\u003eHuang R, Liu X, He L, Zhou P-K. Radiation Exposure Associated With Computed Tomography in Childhood and the Subsequent Risk of Cancer: A Meta-Analysis of Cohort Studies. Dose-Response. 2020;18(2). doi:10.1177/1559325820923828\u003c/li\u003e\n\u003cli\u003eIAEA. (2020). \u003cem\u003eRadiological protection of patients: Diagnostic reference levels in medical imaging\u003c/em\u003e.\u003c/li\u003e\n\u003cli\u003eInko-Tariah, M. B., Okparavero, J., \u0026amp; Azih, C. C. (2019). Radiation protection practices in paediatric radiology: Survey of Nigerian diagnostic centers. \u003cem\u003eJournal of Radiography and Imaging\u003c/em\u003e, 34(3), 145-150.\u003c/li\u003e\n\u003cli\u003eJoseph Zira, D., Haruna Yahaya, T., Umar, M. S., Nkubli B, F., Chukwuemeka, N. C., Sidi, M., Emmanuel, R., Ibrahim, F. Z., Laushugno, S. S., \u0026amp; Ogenyi, A. P. (2021). Clinical indication-based diagnostic reference levels for paediatric head computed tomography examinations in Kano Metropolis, northwestern Nigeria. Radiography, 27(2), 617-621.\u003c/li\u003e\n\u003cli\u003eKhong, P. L., Ringertz, H., Donoghue, V., et al. (2017). Optimizing paediatric imaging: Role of DRLs. \u003cem\u003ePaediatric Radiology\u003c/em\u003e, 47(\u003c/li\u003e\n\u003cli\u003eLin, J., Zhang, J., Anzia, L., \u0026amp; Hayes, L. L. (2023). Failure to Adjust CT Scanners to Paediatric Settings is a Major Cause of Unnecessary Radiation Exposure to Children.\u003c/li\u003e\n\u003cli\u003eMuhammad, N. A., Abdul Karim, M. K., Abu Hassan, H., Ahmad Kamarudin, M., Ding Wong, J. H., \u0026amp; Ng, K. H. (2020). Diagnostic reference level of radiation dose and image quality among paediatric CT examinations in a tertiary hospital in Malaysia. Diagnostics, 10(8), 591.\u003c/li\u003e\n\u003cli\u003eMuhammad, N. A., Sabarudin, A., Ismail, N., \u0026amp; Karim, M. K. A. (2021). A systematic review and meta-analysis of radiation dose exposure from computed tomography examination of thorax-abdomen-pelvic regions among paediatric population. \u003cem\u003eRadiation Physics and Chemistry\u003c/em\u003e, \u003cem\u003e179\u003c/em\u003e, 109148.\u003c/li\u003e\n\u003cli\u003eRehani, M. M., \u0026amp; Frush, D. P. (2018). Tracking radiation exposure of patients for better radiation protection: The IAEA smart card project. \u003cem\u003eRadiation Protection Dosimetry\u003c/em\u003e, 183(2), 193-197. https://doi.org/10.1093/rpd/ncy176\u003c/li\u003e\n\u003cli\u003eSatharasinghe, D., Jeyasugiththan, J., Wanninayake, W. M. N. M. B., \u0026amp; Pallewatte, A. S. (2021). Paediatric diagnostic reference levels in computed tomography: a systematic review. Journal of Radiological Protection, 41(1), R1.\u003c/li\u003e\n\u003cli\u003eSatharasinghe, D., Jeyasugiththan, J., Wanninayake, W. M. N. M. B., Pallewatte, A. S., \u0026amp; Samarasinghe, R. A. N. K. K. (2022). Patient size as a parameter for determining diagnostic reference levels for paediatric computed tomography (CT) procedures. Physica Medica, 102, 55-65.\u003c/li\u003e\n\u003cli\u003eVassileva, J., \u0026amp; Rehani, M. M. (2015). Diagnostic reference levels. \u003cem\u003eAmerican Journal of Roentgenology\u003c/em\u003e, 204(1), 47-53. https://doi.org/10.2214/AJR.14.12592\u003c/li\u003e\n\u003cli\u003eWagner, F., Bize, J., Racine, D., Le Coultre, R., Verdun, F., Trueb, P. R., \u0026amp; Treier, R. (2018). Derivation of new diagnostic reference levels for neuro-paediatric computed tomography examinations in Switzerland. Journal of Radiological Protection, 38(3), 1013.\u003c/li\u003e\n\u003cli\u003eYang, F., \u0026amp; Gao, L. (2024). Age-based diagnostic reference levels and achievable doses for paediatric CT: a survey in Shanghai, China.\u003c/li\u003e\n\u003cli\u003eZalokar, N., Žager Marciu\u0026scaron;, V., \u0026amp; Meki\u0026scaron;, N. (2020). Establishment of national diagnostic reference levels for radiotherapy computed tomography simulation procedures in Slovenia. European Journal of Radiology, 127, 108979.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"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":"","lastPublishedDoi":"10.21203/rs.3.rs-6805307/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6805307/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003ePediatric computed tomography (CT) imaging presents complex challenges in radiation dose management. This study analyzed 608 pediatric CT examinations, revealing significant variations in demographic characteristics, machine parameters, and radiation exposure. Key findings indicated a predominance of male participants (60.2%), with head and brain scans comprising 89% of examinations. Contrast-enhanced studies demonstrated substantially higher radiation doses, with mean Computed Tomography Dose Index (CTDI) of 45.08\u0026thinsp;\u0026plusmn;\u0026thinsp;21.53 mGy compared to 22.95\u0026thinsp;\u0026plusmn;\u0026thinsp;8.45 mGy for non-contrast procedures. Machine parameters showed considerable variability, with kilovoltage ranging from 80\u0026ndash;125 and milliamperage from 50\u0026ndash;450. Head and brain scans exhibited the highest radiation exposure (CTDI 52.26 mGy, DLP 1182.24 mGy\u0026middot;cm), while chest examinations reported the lowest (CTDI 13.95 mGy, DLP 238.30 mGy\u0026middot;cm). The study underscores the critical need for age-specific and weight-based CT protocol optimization, careful contrast medium usage, and continuous radiation exposure monitoring in pediatric imaging. These findings contribute to the ongoing global effort to minimize radiation risks while maintaining diagnostic image quality\u003c/p\u003e","manuscriptTitle":"Dose Reference Level for Paediatric Computed Tomography Examinations at a Private Diagnostic Centre, Benin City","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-04 12:47:35","doi":"10.21203/rs.3.rs-6805307/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":"35770aff-efbe-41d2-9bf1-a6f94489e230","owner":[],"postedDate":"June 4th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-06-20T22:08:19+00:00","versionOfRecord":[],"versionCreatedAt":"2025-06-04 12:47:35","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6805307","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6805307","identity":"rs-6805307","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}