Paediatric Diagnostic Reference Levels Research Articles

Expansion of Typical Values for Paediatric Patients in Ireland and Comparison with Published DRLs - Experiences of a Single Institution

IntroductionTo reduce the risks involved with ionising radiation exposure, typical values (TVs) and diagnostic reference levels (DRLs) have been established to help keep radiation doses ‘as low as reasonably practicable. TVs/DRLs provide standardised radiation dose metrics that can be used for comparative purposes. However, for paediatrics, such values should consider the size of the child instead of their age. This study aimed to establish and compare paediatric TVs for chest, abdomen and pelvis radiography. MethodsStudy methods followed processes for establishing paediatric DRLs as outlined by the Health Information and Quality Authority (HIQA). Kerma-area product (KAP) values, excluding rejected images, were retrospectively acquired from the study institution's Picture Archiving and Communications System (PACS). Paediatric patients were categorised into the following weight-based groupings (5 to <15 kg, 15 to <30 kg, 30 to <50 kg, 50 to 80 kg) and stratified based on the examination that was performed (chest, abdomen, and pelvis), and where it was performed (the different X-ray rooms). Anonymised data were inputted into Microsoft Excel for analysis. Median and 3rd quartile KAP values were reported together with graphical illustrations. ResultsData from 407 X-ray examinations were analysed. For the previously identified weight categories (5 to <15 kg, 15 to <30 kg, 30 to <50 kg, 50 to 80 kg), TVs for the chest were 0.10, 0.19, 0.37 and 0.53 dGy.cm2, respectively. For the abdomen 0.39, 1.04, 3.51 and 4.05 dGy.cm2 and for the pelvis 0.43, 0.87, 3.50 and 7.58 dGy.cm2. Between X-ray rooms TVs varied against the institutional TVs by -60 to 119 % (chest), -50 to 103 % (abdomen) and -14 and 24 %% (pelvis). ConclusionTVs in this study follow established trends with patient weight and examination type and are comparable with published literature. Variations do exist between individual examination rooms and reasons are multifactorial. Given that age and size do not perfectly correlate further work should be undertaken around weight-based TVs/DRLs in the paediatric setting.

Comparison of typical radiation doses and risks using an anthropomorphic 'bone fracture' phantom for commonly performed X-ray projections in a 5-year-old.

Diagnostic reference levels (DRLs) are typical dose levels for medical imaging examinations for groups of standard-sized patients or standard phantoms for broadly defined types of equipment used as a tool to aid optimisation of protection for medical exposures. Currently, there are no paediatric DRLs for conventional radiography (i.e. general X-rays) published in Australia. The aim of this study was to establish typical radiation doses and risks that are representative of those delivered for commonly performed X-ray projections for a 5-year-old/20 kg child using a 5-year-old anthropomorphic 'bone fracture' phantom in three dedicated paediatric radiology departments in Victoria. A total of 20 projection images were acquired for a standard 5-year-old/20 kg phantom using digital radiography X-ray equipment. The air kerma-area product (KAP) measured at each centre by a KAP metre, which was calibrated to a national primary standard, was considered to represent the median value for that centre for each X-ray projection. Organ doses and effective dose were estimated using PCXMC software, and risks of radiation-induced cancer and radiation-induced death were calculated based on the BEIR VII report. The typical doses for the individual X-ray projections ranged from 3 mGy•cm2 to 86 mGy•cm2 , whilst the effective doses ranged from 0.00004 to 0.07 mSv. The radiation risks were 'minimal' to 'negligible'. The estimation of typical radiation doses and associated risks for a 5-year-old/20 kg phantom study provides reference values for guidance and is a first step in assisting optimisation at other institutions until national DRLs, based on patient data from the clinical setting, are published.

Establishing national diagnostic reference levels in radiography, mammography, and dual-energy x-ray absorptiometry services in Ireland and comparing these with European diagnostic reference levels.

The aim of this work was to establish national diagnostic reference levels (DRLs) in Ireland and compare these to existing European DRLs where available. This work surveyed all radiological facilities providing radiography, mammography, and dual-energy x-ray absorptiometry (DXA) services in Ireland. A list of common procedures and clinical tasks was established. A national database of service providers was used to identify the appropriate medical radiological facilities providing these services. These facilities were issued with an online survey. National DRLs were set as the 75th percentile of the distribution of median values obtained. A national median dose was also established. The broad categorisation of equipment type was also considered. Where differences between DRLs established using different detector types were deemed statistically significant, equipment-specific national DRLs were established. National DRLs were established for 12 adult radiography projections. Equipment-specific (computed radiography and digital radiography) adult DRLs were established for four radiography projections. Paediatric DRLs were established for 11 radiography projections, including two based on clinical indications, for a range of paediatric weight categories. National DRLs were established for unilateral two-view mammography and breast tomosynthesis as well as for four DXA clinical indications and projections. All but one Irish DRL figure was found to be below or equal to European data. This work provided a unique opportunity to establish national DRLs based on census data for a range of procedures and clinical tasks across radiography, mammography and DXA and compare these with European levels. This work established national diagnostic reference levels (DRLs) based on census data for a range of procedures and clinical tasks across radiography, mammography and dual-energy x-ray absorptiometry. The establishment of national DRLs is an essential component in the optimisation of patient radiation dose. • Diagnostic reference levels are easily measured quantities intended for use as an aid to optimise patient dose and to identify when levels of patient dose are unusually high. • Data from all medical radiological facilities in Ireland was obtained to establish national diagnostic reference level (DRL) values and national median dose values in radiography, x-ray breast imaging and dual-energy x-ray absorptiometry (DXA) scanning and these were compared to existing European DRLs where available. • National DRL values were established for the first time in breast tomosynthesis, DXA scanning, and paediatric radiography.

A practical guide for paediatric diagnostic reference levels (PiDRLs)

This guide was designed to provide a foundation for developing paediatric diagnostic reference levels (PiDRLs) for conventional radiography. In principle, the calculation of diagnostic reference levels (DRLs) is recommended for diagnostic x-ray imaging examinations for radiosensitive patients, such as paediatric patients. PiDRLs are fundamentally important when considering dose optimisation in diagnostic radiology, computed tomography and interventional radiology for paediatric patients. DRLs can assist to point to non-optimised practices and the improvement of paediatric dose optimisation. The purpose of this continuing medical education article is to give medical radiation professionals an overview of PiDRLs for conventional radiography, an understanding of the benefits, the data collection process and some of the calculation methods. The readers can use these steps to establish and implement PiDRLs for different examinations.

Paediatric diagnostic reference levels for common radiological examinations using the European guidelines.

Objective:The purpose of this study was to explore the feasibility to determine regional diagnostic reference levels (RDRLs) for paediatric conventional and CT examinations using the European guidelines and to compare RDRLs derived from weight and age groups, respectively.Methods:Data were collected from 31 hospitals in 4 countries, for 7 examination types for a total of 2978 patients. RDRLs were derived for each weight and age group, respectively, when the total number of patients exceeded 15.Results:It was possible to derive RDRLs for most, but not all, weight-based and age-based groups for the seven examinations. The result using weight-based and age-based groups differed substantially. The RDRLs were lower than or equal to the European and recently published national DRLs.Conclusion:It is feasible to derive RDRLs. However, a thorough review of the clinical indications and methodologies has to be performed previous to data collection. This study does not support the notion that DRLs derived using age and weight groups are exchangeable.Advances in knowledge:Paediatric DRLs should be derived using weight-based groups with access to the actual weight of the patients. DRLs developed using weight differ markedly from those developed with the use of age. There is still a need to harmonize the method to derive solid DRLs for paediatric radiological examinations.

Establishing paediatric diagnostic reference levels using reference curves - A feasibility study including conventional and CT examinations.

To derive Regional Diagnostic Reference Levels (RDRL) for paediatric conventional and CT examinations using weight-based DRL curves and compare the outcome with DRL derived using the weight groups. Data from 1722 examinations performed at 29 hospitals in four countries were included. DRL was derived for four conventional x-ray (chest, abdomen, pelvis, hips/joints) and two types of CT examinations (thorax, abdomen). DRL curves were derived using an exponential fit to the data using weight as an independent variable and the respective radiation dose indices (PKA, CTDIvol, DLP) as dependent variables. DRL was also derived for weight groups for comparison. The result was compared with national diagnostic reference level (NDRL) curves. The derived curves show similarities with the NDRL curves available and corresponded sufficiently well with DRL for weight groups using the same data set, if sufficient number of data was available. We conclude that weight-based DRL curves are a feasible approach and could be used together with DRL for weight groups. The main advantage of DRL curves is its application in the clinic. When the examination frequency is low, time to collect enough data to establish typical values for one or several weight groups may be unreasonably long. The curve provides the means to compare dose level faster and with fewer data points.

Local Diagnostic Reference Levels for Paediatric Head CT Procedures.

Background.Patients, especially children, are exposed to substantially high doses of ionising radiation during computed tomography (CT) procedures. Children are several times more susceptible to ionising radiation than adults. Diagnostic reference levels (DRLs) are an important tool for monitoring and optimising patient radiation exposure from radiological procedures. The aim of this study is to estimate the ionising radiation exposure doses and set local DRLs for head CT examinations according to age and to compare local DRLs with national and European DRLs and with literature data in other countries.Materials and methods.Scan parameters of single-phase head CT examinations were collected. Patients were grouped by age in the following intervals: <1, 1−5, 5−10, 10−15 and 15−18 years. Local age-based DRLs set as the 3rd quartile of the median dose-length product (DLP) were calculated. Literature analysis was performed on PubMed search engine on inclusion criteria: publication date 2015–2020, used keywords paediatric computed tomography, paediatric CT, diagnostic reference levels (DRLs). The 23 articles discussing paediatric DRLs were further analysed.Results.Data was collected from 194 paediatric head CT examinations performed in 2019. The median DLP values for head CT were 144.3, 233.7, 246.4, 288.9, 315.5 for <1, 1−5, 5−10, 10−15 and 15−18 years old groups. Estimated local DRLs for head CT examinations are 170, 300, 310, 320, 360 mGy*cm for <1, 1−5, 5−10, 10−15 and 15−18 years age groups respectively and 130, 210, 275, 320 mGy*cm for 0−3 months, 3 months−1 year, 1−6 years and ≥ 6 years age groups respectively. Conclusions.Results of this study showed that settled new local DRLs of head CT examinations were 2–4 times lower than national DRLs and about 2 times lower than European DRLs. Moreover, the study indicated that paediatric head CT doses are significantly lower in comparison with those indicated in the majority of published data from other hospitals over the last 6 years. Patient dose assessment and local DRLs establishment plays important role in future exposure optimisation.

Paediatric Diagnostic Reference levels in low Resource Settings: A Guide for developing Country Practitioners with excerpts from ICRP 135

Background: The practical implementation of Diagnostic Reference Level in pediatric imaging is a complex task due to their unique individuality in terms of high sensitivity to radiation, varying body sizes and presenting pathology. Hence, good knowledge of medical technology, skill to perform patient dosimetry and to analyze mage quality is required.&#x0D; Purpose: To provide a guide on the methodological requirements for the establishment of Paediatric Diagnostic Reference Levels (PiDRLs) based on the revised and updated guidelines from the current ICRP publication 135 on Diagnostic Reference Levels (DRLs).&#x0D; Materials and method: An extensive review of the ICRP report Publication 135 on Diagnostic Reference levels in medical imaging with a focus on paediatric imaging and other related studies were undertaken. &#x0D; Results: The ICRP report 135 updates and refines the recommendations of 2001. It highlights that the application of DRLs in paediatrics alone is not sufficient for the optimization of protection. Image quality must be evaluated. Quantities used for DRLs should be appropriate to the imaging modality being evaluated, assess the amount of ionizing radiation applied to perform a medical imaging task, and be measured directly. For interventional procedures, the complexity of the procedure may be considered in setting DRLs. DRLs shall not be used for individual patients or as trigger (alert or alarm) levels for individual patients. Appropriate weight bands (generally with 5 or 10 kg intervals) are recommended for establishing paediatric DRLs and should be promoted.&#x0D; Conclusion: The amount of radiation used for examinations of children can vary tremendously due to the great variation in patient size and weight from neonates to adult-sized adolescents. This variation in patient radiation dose is appropriate. However, variation in patient doses due to inappropriate technique or failure to child-size the imaging protocol is not appropriate. This forms the basis of the new ICRP guideline and should form the basis of developing PiDRLs.

An audit of radiation doses received by paediatric patients undergoing computed tomography investigations at academic hospitals in South Africa.

BackgroundDiagnostic reference levels (DRLs) are a crucial element of auditing radiation doses in paediatric computed tomography (CT). Currently, there are no national paediatric CT DRLs in South Africa.ObjectivesThe aim of this article was to establish local paediatric DRLs for CT examinations at two academic hospitals and to compare paediatric CT radiation output levels with established DRLs in the developed and developing world.MethodComputed Tomography Dose Indexvolume (CTDIvol) and dose length product (DLP) values were collected from CT examinations performed at two university hospitals for patients aged 0–15 years, during 01 November 2016–30 April 2017. The 75th percentile of the data distribution was calculated for each CT examination type and age group, further categorised into routine working hours and after-hours for both hospitals and statistically compared.ResultsOf the 1031 CT examinations performed, CT brain examination was the most common (755/1031; 72.23%). DLP values were increased in the after-hours categories compared to regular working hours at both hospitals. The largest increase was in the 0–1 year age group (150.56%). With the exception of CT Chest and CT abdomen in the 0–1 year age group, the CTDIvol and DLP values compared favourably to international standards.ConclusionMost of the calculated DRLs are acceptable and internationally comparable. This likely indicates effective reduction techniques and protocols. Computed tomography body examination protocols for 0–1 year patients should be reviewed. Strategies should be implemented to limit higher doses in after-hours examinations.

Paediatric Diagnostic Reference levels in low Resource Settings: A Guide for Developing Country Practitioners with excerpts from ICRP

Background: The practical implementation of Diagnostic Reference Level in paediatric imaging is a complex task due to their unique individuality in terms of high sensitivity to radiation, varying body sizes and presenting pathology. Hence, good knowledge of medical technology, skill to perform patient dosimetry and to analyze mage quality is required. Purpose: To provide a guide on the methodological requirements for the establishment of Paediatric Diagnostic Reference Levels (PiDRLs) based on the revised and updated guidelines from the current ICRP publication 135 on Diagnostic Reference Levels (DRLs). Materials and method: An extensive review of the ICRP report Publication 135 on Diagnostic Reference levels in medical imaging with a focus on paediatric imaging and other related studies were undertaken. Results: The ICRP report 135 updates and refines the recommendations of 2001. It highlights that the application of DRLs in paediatrics alone is not sufficient for the optimization of protection. Image quality must be evaluated. Quantities used for DRLs should be appropriate to the imaging modality being evaluated, assess the amount of ionizing radiation applied to perform a medical imaging task, and be measured directly. For interventional procedures, the complexity of the procedure may be considered in setting DRLs. DRLs shall not be used for individual patients or as trigger (alert or alarm) levels for individual patients. Appropriate weight bands (generally with 5 or 10 kg intervals) are recommended for establishing paediatric DRLs and should be promoted. Conclusion: The amount of radiation used for examinations of children can vary tremendously due to great variation in patient size and weight from neonates to adult-sized adolescents. This variation in patient radiation dose is appropriate. However, variation in patient doses due to inappropriate technique or failure to child-size the imaging protocol is not appropriate. This forms the basis of the new ICRP guideline and should form the basis of developing PiDRLs.

Assessment of Regional Pediatric Diagnostic Reference Levels for Panoramic Radiography Using Dose Area Product.

Aim:The current work aims to calculate dose area product (DAP) and to determine regional diagnostic reference level (DRL) for pediatric panoramic radiography in Tamil Nadu.Materials and Methods:In this study, DAP was calculated after finding the product of air kerma on the detector side of scanner with the corresponding exposed area. The obtained DAP values were further analyzed, and DRL was calculated using Microsoft Excel. The study was carried out with routine pediatric exposure parameters.Results:The obtained mean, range, and third quartile values for pediatric panoramic radiography are found to be 65 mGycm2, 11–148 mGycm2, and 82 mGycm2, respectively. The proposed DRL is comparable with the other countries' DRL.Conclusion:Based on the results of the present study, it was observed that there exists a wide difference in mean doses among the panoramic scanners. The variation in radiation doses between the clinics/hospitals and similar scanners suggests a large potential for optimization of panoramic procedures.

RADIATION EXPOSURE OF PAEDIATRIC GENERAL RADIOGRAPHY, FLUOROSCOPY AND CT PROCEDURES IN THE CZECH REPUBLIC-PILOT STUDY.

The pilot dose survey on paediatric general radiography, fluoroscopy and CT procedures was performed in four university hospitals. The analysis of data was focused on the radiography and CT imaging of head, chest, abdomen, pelvis and spine and fluoroscopic procedures of gastrointestinal and urinary tracts. The survey was conducted by the National Radiation Protection Institute. Two hospitals exported data from the patient dose management system, while the others collected the data manually. The methodology of diagnostic reference levels assessment was proposed and tested. Local diagnostic reference levels were calculated in terms of air kerma-area product $P_{KA}$, CT air kerma-length product $P_{KL,CT}$ and volumetric CT air kerma index $C_{VOL}$. The lack of procedure standardisation, e.g. in tube voltage setting irrespective of patient's weight, was revealed at one hospital. Dose and exposure parameters distributions with respect to patient's anatomical constitution are presented in this article. In future, this pilot study will be a base for national survey of paediatric diagnostic reference levels.

LOCAL DRLS FOR PAEDIATRIC CT EXAMINATIONS BASED ON SIZE-SPECIFIC DOSE ESTIMATES IN KERMANSHAH, IRAN.

Due to the radiosensitivity of paediatric patients to X-ray, it is necessary to survey the paediatric DRLs using size-specific dose estimates (SSDE). In the present study, we determined the local diagnostic reference levels (DRLs) for paediatric chest, head and abdomen-pelvis CT examinations and their Surview scans in Kermanshah city, Iran. For ≤1 year, 1-5 years, 5-10 years and 10-15 years the DRLs (mGy) based on SSDE were determined N/A, 6.00, 6.25, 8.27 for abdomen-pelvis, and 8.74, 7.45, 11.15, 10.45 for chest and 19.05, 18.33, 18.22, 20.14 for head examinations, respectively. The differences between body size and default phantom defined in CT scanners are significant and should be considered when determining the DRLs. Based on our findings, use of CTDIv and SSDE parameters for determining DRLs leads to significant different results in children; thus SSDE is suggested as a more accurate index than CTDIV for establishing DRLs in paediatric CT examinations.

European Society of Paediatric Radiology Computed Tomography and Dose Task Force: European guidelines on diagnostic reference levels for paediatric imaging.

The recent European Council Directive 2013/59/EURATOM requires the establishment of diagnostic reference levels (DRLs) to optimise radiation dose in diagnostic and interventional radiology procedures. At the time this directive was enacted, just a few European countries had already set paediatric DRLs and many of these were outdated. For this reason, the European Commission launched a project addressing European Guidelines on Diagnostic Reference Levels for Paediatric Imaging that was awarded to a consortium led by the European Society of Radiology with the collaboration of the European Society of Paediatric Radiology and other European stakeholders involved in the radiation protection of children. The main aims of this project were to establish European DRLs to be used by countries without their own national paediatric DRLs and to provide a consistent method to establish new DRLs in the future. These European guidelines have been very recently endorsed by the European Commission and published in issue N° 185 of the Radiation Protection series. The purpose of this article is to introduce these guidelines to the wide community of paediatric radiologists.

Paediatric Dose AssessmentToward Establishment of National Diagnostic Reference Levels for Digital Radiography Examinations in Iran

Introduction: Paediatric patients deserve special attention because of the higher radiation risks compared with adults. The main purpose of this study is to determine patient dose and diagnostic reference level for Paediatric through Entrance Surface Dose (ESD) calculations in common X-ray examination and to establish Paediatric national DRLs in digital radiography in Iran. Materials and Methods: The study was performed on 5260 patients in 53 X-ray room. They are classified into four age groups, 0>1 year, 1>5 years, 5>10 years and 10>15 years old. Skull (PA), Skull (Lat), Chest (PA), Chest (Lat), Pelvis(AP), Abdomen (AP) digital X-ray examination is done for them. The dosimetry protocol in this study was indirect method to measure Entrance Surface Air Kerma (ESAK). The X-ray tube output for each equipment is measured using RTI solid state detector (Model Barracuda). Finally, the third quarter determined diagnostic reference level. Results: Based on the results of this study, national diagnostic reference levels were established: for example, for age group 0 to 1-year-old: 0.51 mGy for Skull(AP/PA), 0.46 mGy for Skull(Lat), 0.11 mGy for Cervical spine(AP), 0.11 mGy for Cervical spine(Lat), 0.06mGy for Chest(PA), 0.08 mGy Chest(Lat), 0.15 mGy for Thoracic spine(AP), 0.26 mGy for Thoracic spine (Lat), 0.48 mGy for Lumbar spine (AP), 0.74 mGy for Lumbar spine(Lat), 0.47 mGy for Pelvis (AP) and 0.47 mGy for Abdomen (AP). Conclusion: This article has determined wide variations in radiation dose of x-ray examinations among hospitals in Iran. Application of a diagnostic reference levels (DRL) could be a optimization procedure for reducing patients dose. The survey reveals significant variations in the radiological practices.

Assessment of Regional Pediatric Computed Tomography Dose Indices in Tamil Nadu.

The aim of this article is to assess Tamil Nadu pediatric computed tomography (CT) diagnostic reference levels (DRLs) by collecting radiation dose data for the most commonly performed CT examinations. This work was performed for thirty CT scanners installed in various parts of the Tamil Nadu region. The patient cohort was divided into two age groups: <1 year, and 1–5 years. CT dose indices were measured using a 10 cm3 pencil ion chamber with pediatric head and body polymethyl methacrylate phantoms. Dose data such as volumetric CT dose index (CTDIv) and dose length product (DLP) on a minimum of twenty average-sized pediatric patients in each category were recorded to calculate a mean site CTDIv and DLP value. The rounded 75th percentile was used to calculate a pediatric DRL for each hospital, and then region by compiling all results. Data were collected for 3600 pediatric patients. Pediatric CT DRL for two age groups: <1 year (CTDIv and DLP of head [20 mGy, 352 mGy.cm], chest [7 mGy, 120 mGy.cm] and abdomen [12 mGy, 252 mGy.cm]), and 1–5 years (CTDIv and DLP of head [38 mGy, 505 mGy.cm], chest [8 mGy, 132 mGy.cm] and abdomen [14 mGy, 270 mGy.cm]) for select procedures have been calculated. Proposed pediatric DRLs of CTDIv and DLP for head procedure were lower, and for chest and abdomen procedures were higher than European pediatric DRLs for both age groups.

Establishing and monitoring DRLS

Diagnostic Reference Levels (DRLs) have proven to be an effective tool for dose optimisation of protection in medical imaging. The ‘Euratom Basic Safety Standards’ states that ‘Member States shall ensure the establishment, regular review and use of diagnostic reference levels for radiodiagnostic examinations, having regard to the recommended European diagnostic reference levels where available, and when appropriate, for interventional radiology procedures, and the availability of guidance for this purpose’. The ‘European DRLs for Paediatric Imaging’ project (abbreviation: PiDRL) has very recently developed European Guidelines on how to establish and how to use paediatric DRLs. DRLs should be established primarily for examinations that significantly contribute to the collective effective dose of the patient population. DRLs should be based on appropriate patient dose surveys. In general, it is recommended that from each institution a representative sample of at least 10 patients per procedure type and per patient group is needed for non-complex examinations such as radiography and CT and at least 20 patients per procedure type for complex procedures such as fluoroscopy and fluoroscopically guided procedures. For all body examinations, weight should be used as a parameter for patient grouping. Patient dose data should be collected from a representative sample of various types of equipment and practices in the geographical area concerned. Dose management solutions can play a very important role in the establishment and use of DRLs.

Diagnostic reference levels in low- and middle-income countries: early "ALARAm" bells?

Background In 1996 the International Commission on Radiological Protection (ICRP) introduced diagnostic reference levels (DRLs) as a quality assurance tool for radiation dose optimization. While many countries have published DRLs, available data are largely from high-income countries. There is arguably a greater need for DRLs in low- and middle-income-countries (LMICs), where imaging equipment may be older and trained imaging technicians are scarce. To date, there has been no critical analysis of the published work on DRLs in LMICs. Such work is important to evaluate data deficiencies and stimulate future quality assurance initiatives. Purpose To review the published work on DRLs in LMICs and to critically analyze the comprehensiveness of available data. Material and Methods Medline, Scopus, and Web of Science database searches were conducted for English-language articles published between 1996 and 2015 documenting DRLs for diagnostic imaging in LMICs. Retrieved articles were analyzed and classified by geographical region, country of origin, contributing author, year of publication, imaging modality, body part, and patient age. Results Fifty-three articles reported DRLs for 28 of 135 LMICs (21%), reflecting data from 26/104 (25%) middle-income countries and 2/31 (6%) low-income countries. General radiography (n = 26, 49%) and computerized tomography (n = 17, 32%) data were most commonly reported. Pediatric DRLs (n = 14, 26%) constituted approximately one-quarter of published work. Conclusion Published DRL data are deficient in the majority of LMICs, with the paucity most striking in low-income countries. DRL initiatives are required in LMICs to enhance dose optimization.

Establishment of local diagnostic reference levels in paediatric screen-film radiography at a children'shospital

To assess the frequency of examination, image quality (IQ) and establishment of local diagnostic reference levels (LDRLs) in paediatric radiographic examinations. The X-ray device performance, film reject rate and IQ grading were assessed at Radiology Department of a referral and teaching children's hospital in Kenya. A questionnaire method was developed and used in recording the exposure factors used to indirectly calculate patient doses. The study established the first age- and technique-specific diagnostic reference levels (DRLs) for paediatric patients with respect to grid and non-grid radiographic techniques. The mean doses in most grid examinations exceeded the available international DRLs. The non-grid radiography imaging technique provided better IQ and an optimal patient dose. In this study, the preliminary age-specific paediatric DRLs, based on the mean values of the dose distribution, have been suggested for the type of examination considered. They form the preliminary LDRLs, which are lower than the few available international DRLs.

Le point sur les niveaux de référence diagnostiques en médecine nucléaire en 2011

Seven years after the publication of the first diagnostic reference levels (DRL) order, the analysis of the data allows the French Institute for radiation protection and nuclear safety (IRSN) to assess and evaluate the increase of the nuclear medicine departments involvement and of the level administered activities to the patients during the most common examinations performed in France. IRSN analyses show a good agreement between the distribution of transmitted examinations and the frequency of examinations performed in France, taking into account 95% of the number of examinations and 95% of the dose delivered to patients by nuclear medicine. These analyses highlight the necessary consistency between DRL regulation, the French society of nuclear medicine (SFMN) recommendations and national practice. The IRSN recommendations established from data analyses have leaded the authorities to publish a new DRL order in January 2012. This first update of the regulation takes into account actual clinical practice in nuclear medicine and introduces fundamental points as pediatric DRL. In the future, periodical updates will be implemented in order to take into account procedures and devices evolutions.