OWSD Nigeria National Chapter presents RADIATION RISKS ASSOCIATED WITH X- RAY EXAMINATIONS IN CHILDREN FROM A TERTIARY HEALTH FACILITY IN PORT HARCOURT
March 12, 2025
OWSD Nigeria University of Port Harcourt Branch Series of Scientific Communication: Lilian C. Ogbonna on RADIATION RISKS ASSOCIATED WITH X- RAY EXAMINATIONS IN CHILDREN
RADIATION RISKS ASSOCIATED WITH X- RAY EXAMINATIONS IN CHILDREN FROM A TERTIARY HEALTH FACILITY IN PORT HARCOURT, NIGERIA
BY
LILIAN C. OGBONNA
Abstract
X-ray imaging is a crucial diagnostic tool in modern medicine, but excessive exposure to ionizing radiation poses significant health risks, particularly for children, who are more radiosensitive than adults. This study evaluates the radiation risks associated with pediatric X-ray examinations at Rivers State University Teaching Hospital (RSUTH), Port Harcourt, Nigeria.
A sample of 20 pediatric patients undergoing X-ray procedures was analyzed. Radiation dose parameters, including Entrance Surface Dose (ESD), Absorbed Dose, and Excess Lifetime Cancer Risk (ELCR), were measured and compared with international safety standards set by the International Commission on Radiological Protection (ICRP) and the World Health Organization (WHO). The results revealed that some ESD values exceeded recommended limits, indicating an increased risk of radiation-induced health effects over time.
The study underscores the need for radiation dose optimization in pediatric imaging and recommends the implementation of national Diagnostic Reference Levels (DRLs), regular calibration of X-ray machines, and enhanced training for radiographers to ensure adherence to ALARA (As Low As Reasonably Achievable) principles. These findings are critical for improving pediatric radiation safety, reducing unnecessary exposure, and enhancing the quality of diagnostic imaging.
1. Introduction
Medical imaging plays a vital role in modern healthcare, aiding in the diagnosis and treatment of various medical conditions. X-ray examinations are among the most commonly used imaging techniques due to their efficiency and accessibility. However, ionizing radiation exposure poses significant health risks, particularly for children, who are 2–3 times more sensitive to radiation than adults due to their rapidly dividing cells and longer life expectancy. Studies have linked excessive radiation exposure in childhood to an increased risk of cancer, genetic mutations, and other long-term health complications.
In response to these risks, international organizations such as the International Commission on Radiological Protection (ICRP) and the World Health Organization (WHO) have established Diagnostic Reference Levels (DRLs) to minimize radiation exposure while maintaining image quality. However, in many developing countries, including Nigeria, adherence to these guidelines remains inconsistent, leading to concerns about radiation dose optimization in pediatric imaging.
This study focuses on evaluating the radiation risks associated with pediatric X-ray examinations at Rivers State University Teaching Hospital (RSUTH), Port Harcourt, Nigeria. It aims to:
- Measure Entrance Surface Dose (ESD), Absorbed Dose, and Excess Lifetime Cancer Risk (ELCR) in pediatric patients.
- Compare observed dose levels with international safety standards (ICRP, WHO).
- Assess the need for improved radiation protection protocols in pediatric imaging.
By identifying potential radiation hazards and recommending best practices, this research contributes to ensuring safer diagnostic imaging for children, reducing unnecessary exposure, and enhancing compliance with international safety guidelines.
2. Methodology
This study was conducted at Rivers State University Teaching Hospital (RSUTH), Port Harcourt, Nigeria, to assess the radiation risks associated with pediatric X-ray examinations. The methodology involved data collection, dose measurement using optically stimulated dosimeters (OSDs), and comparative analysis against international safety standards.
2.1 Study Design and Sample Selection
A quantitative, observational approach was used to analyze radiation exposure levels in pediatric patients undergoing routine X-ray examinations. A total of 20 pediatric patients aged 0–14 years were selected for the study. The sample included children undergoing chest, abdomen, and limb X-rays, which are among the most commonly performed radiographic procedures in pediatric radiology.
2.2 Data Collection
The following radiation parameters were recorded for each patient:
- Tube Voltage (kVp): Determines the penetration power of X-rays.
- Tube Current-Time Product (mAs): Controls the number of X-rays produced.
- Focus-to-Skin Distance (FSD): The distance between the X-ray tube and the patient’s skin.
- Exposure Time: Duration of radiation exposure.
2.3 Radiation Dose Measurement Using Optically Stimulated Dosimeters (OSDs)
Radiation dose measurements were obtained using Optically Stimulated Dosimeters (OSDs), a highly sensitive and accurate method for assessing patient dose exposure. The key dose parameters analyzed were:
1. Entrance Surface Dose (ESD) – Measures the radiation dose at the patient’s skin level
2. Absorbed Dose – The amount of radiation energy deposited in body tissues.
3. Effective Dose – Evaluates the overall radiation risk to the patient’s organs
4. Excess Lifetime Cancer Risk (ELCR) – Estimates the increased likelihood of developing radiation-induced cancer over a lifetime.
The OSD readings were analyzed and processed to determine dose variations among different age groups and X-ray procedures.
2.4 Data Analysis
The measured radiation doses were compared with international reference values from:
International Commission on Radiological Protection (ICRP) & World Health Organization (WHO)
Results were presented in tables and graphs to highlight any deviations from safety standards.
3. Results and Discussion
This study evaluated radiation exposure levels in pediatric X-ray examinations at RSUTH, focusing on Entrance Surface Dose (ESD), Absorbed Dose, Effective Dose, and Excess Lifetime Cancer Risk (ELCR). The results were compared with ICRP and WHO safety limits to determine compliance and potential risks.
3.1 Radiation Dose Measurements
The radiation dose parameters measured using Optically Stimulated Dosimeters (OSDs) are presented in the table below.
Table 1: Observed Radiation Dose vs. International Standards
|
Radiation Parameter |
Observed at RSUTH |
ICRP Reference Level |
|
Entrance Surface Dose (ESD) |
0.003 – 0.051 mGy |
0.06 mGy (0-1 yrs), 0.053 mGy (1-5 yrs), 0.49 mGy (6-10 yrs) |
|
Absorbed Dose (Chest X-ray) |
0.006 mGy |
≤ 0.06 mGy |
|
Annual Effective Dose Equivalent (AEDE) |
0.11 – 0.33 mSv/yr |
≤ 1.0 mSv/yr |
|
Excess Lifetime Cancer Risk (ELCR) |
Above 0.29 × 10⁻³ |
≤ 0.29 × 10⁻³ |
Figure 1: Graphical Analysis of Findings
3.3 Discussion of Findings
The ESD values for younger children (0-5 years) exceeded international limits, indicating a higher radiation risk for this age group.
Variations in X-ray exposure settings contributed to dose inconsistencies, emphasizing the need for standardized protocols and dose optimization.
The Excess Lifetime Cancer Risk (ELCR) exceeded WHO thresholds, suggesting an increased likelihood of radiation-induced cancers in pediatric patients.
The findings align with previous studies highlighting the need for stricter radiation protection measures in pediatric imaging.
4. Conclusion and Recommendations
The findings of this study emphasize the need for enhanced radiation protection in pediatric X-ray examinations at Rivers State University Teaching Hospital (RSUTH). The study showed that:
- Entrance Surface Dose (ESD) values exceeded international safety limits, especially for younger children (0–5 years).
- Excess Lifetime Cancer Risk (ELCR) values were higher than WHO's acceptable threshold, indicating a potential long-term risk of radiation-induced cancers.
- Variations in X-ray exposure settings contributed to inconsistencies in radiation doses, highlighting the need for standardized protocols and improved dose optimization.
4.1 Recommendations
To ensure radiation safety in pediatric imaging, the following measures should be implemented:
1. Establish National Diagnostic Reference Levels (DRLs):
Nigeria should develop DRLs for pediatric imaging to standardize dose limits and ensure compliance with international safety guidelines.
2. Optimize Radiation Exposure Settings:
Reduce unnecessary exposure by adjusting kVp, mAs, and FSD settings according to patient age and body size. Enforce ALARA (As Low As Reasonably Achievable) principles to minimize radiation risks.
3. Regular Calibration and Quality Control of X-ray Equipment:
Conduct periodic maintenance and calibration of X-ray machines to ensure accurate dose delivery.
Implement quality assurance programs for consistent radiation safety practices.
4. Training and Continuous Education for Radiographers:
Organize workshops and refresher courses on pediatric radiation safety.
Ensure that radiographers receive training on modern dose optimization techniques and patient positioning.
5. Increase Awareness Among Healthcare Providers and Parents:
Educate medical practitioners on the risks of pediatric radiation exposure.
Encourage alternative imaging techniques (e.g., ultrasound, MRI) where possible to reduce radiation exposure.
4.2 Future Research Directions
Conduct longitudinal studies to track the long-term effects of radiation exposure in children.
Investigate the effectiveness of radiation dose reduction techniques in Nigerian hospital.
Expand the study to multiple healthcare centers to assess national compliance with radiation protection guidelines.
