National Diagnostic Reference Levels Research Articles

National diagnostic reference levels for digital diagnostic and screening mammography in Uganda.

Screening and diagnostic mammography are associated with some risk of radiation-induced breast cancer. This study was conducted to establish the National Diagnostic Reference Levels (NDRLs) for digital diagnostic and screening mammography in Uganda to achieve breast radiation dose optimization. A cross-sectional study was conducted among female participants recruited by consecutive sampling from three selected hospitals with digital mammography in Uganda. The study variables extracted from the mammography machines were exposure factors, compressed breast thickness (CBT), and Average Glandular Dose (AGD) of two standard mammogram views. The stratified National DRL was derived by calculating the 75th percentile of the AGD across all the samples at various CBT ranges for both screening and diagnostic mammography in craniocaudal (CC) and mediolateral oblique (MLO) views. We included 300 participants with mean ages of 50.28±9.32 and 47.45±13.45 years for the screening and diagnostic mammography, respectively. There were statistically significant positive correlations between AGD and exposure factors (mAs, kVp) (all p-values<0.0001). For screening mammography, mAs demonstrated a strong positive correlation (r = 0.8369 in CC, 0.8133 in MLO), whereas kVp showed a positive correlation with relatively lower coefficients (r = 0.3700 in CC, 0.3080 in MLO). For diagnostic mammography, mAs exhibited an even stronger positive correlation (r = 0.8987 in CC, 0.8762 in MLO), and kVp maintained a positive correlation with somewhat lower coefficients (r = 0.4954 in CC, 0.3597 in MLO). In screening mammography, for CBT within the range of (7-39) mm, the NDRLs were (1.5mGy, 1.66mGy) in CC) and MLO views. For CBT in the range of (40-59) mm, the NDRLs were (1.78mGy, 1.87mGy), and for CBT in the range of (60-99) mm, the NDRLs were (2.18mGy, 2.22mGy). For diagnostic mammography, the NDRLs were established as (1.7mGy, 1.91mGy), (2.00mGy, 2.09mGy), and (2.63mGy, 2.81mGy) for CBT ranges of (7-39) mm, (40-59) mm, and (60-99) mm, respectively. The NDRLs for digital screening and diagnostic mammography in Uganda have been proposed for the first time. The NDRL values in mammography should be specific to CBT ranges and mammographic views for both diagnostic and screening mammography.

Development of Dose Calculation Application for Computed Tomography Dose Management When Facility Protocols Differ from Diagnostic Reference Level (DRL)

In this study, we aimed to develop an application that computes dose values resembling diagnostic reference level (DRL) conditions when disparity prevents direct dose comparisons between the national diagnostic reference levels in Japan 2020 (Japan DRLs_2020) and facility-specific computed tomography (CT) protocols. We developed an application using the R programming language and RStudio software that computes dose values and median values based on Japan DRLs_2020 imaging conditions following extraction of necessary information for dose calculations from the Radiation Dose Structured Report (RDSR) and Digital Imaging and Communications in Medicine (DICOM) tags. To ensure a user-friendly experience, we used the Shiny package to develop a graphical user interface that enables the application to operate seamlessly in web browsers. The developed application successfully facilitated the calculation of dose and median values that aligned with the Japan DRLs_2020 for protocols whose imaging range and acquisition timing differed from those of the Japan DRLs_2020. By calculating dose values that align with DRL conditions, our application contributes to the implementation and optimization of dose management in CT for facilities that use diverse imaging protocols.

Evaluation of radiation dose and establishment of local DRLs for adult during abdominopelvic CT scan imaging for university hospital centers, Morocco

Objective: In this study, we have planned to establish the local Diagnostic Reference Levels (DRLs) for the five University Hospital Centers in Morocco and to propose a national DRL for abdominopelvic CT examinations for adult patients. Materials and methods: Data were collected using a specially designed form, which included patient demographics, exposure parameters and dosimetric indicators such as dose-length product (DLP) and CT volume dose index (CTDIvol). The establishment of local and national DRL in terms of CTDIvol and DLP was carried out in accordance with the methodology described in Report 135 of the International Commission on Radiological Protection (ICRP). The effective dose was assessed using the DLP and the dose conversion factor appropriate for this location. Results: A total of 300 patients undergoing abdominopelvic examinations at the five Moroccan university hospitals were collected for this study. Patients' mean age, weight and BMI were (50.97 ± 15.05) years (67.94 ± 11.41) Kg and (25.71 ± 3.03) Kg/m2 respectively. The local DRL, in terms of DLP were 551.56, 2293.33, 709.02, 843.52 and 1059.62 mGy-cm and in terms of CTDIvol were 11,05, 46,40, 13,14, 12,01, 9,88 mGy respectively for UHC-1, UHC-2, UHC-3, UHC-4 and UHC-5 hospitals. The proposed National DRL, defined as a single value for the 75th percentile on the aggregation of data from the five centers, for abdominopelvic scan CT was 773.20 mGy.cm and 12.05 mGy for DLP and CTDIvol, respectively. Conclusion: The Moroccan DRL was comparable to those of other countries, ranking 10th among 21 countries. However, we are still seeking to reduce and optimize radiation dose while maintaining good image quality for reliable diagnosis, and this can be achieved by enhancing radiographers' and radiologists' knowledge of radiation protection, protocol justification, and optimization through rigorous hospital radiation audits at national level.

Establishment of local diagnostic reference levels for breast cancer CT protocols in radiotherapy in a single Moroccan center

The objective of this study was to establish local diagnostic reference levels (LDRLs) for breast cancer computed tomography imaging in radiotherapy (CT-RT) at a single hospital in Morocco. Data were collected from 106 adult breast cancer patients aged between 33 and 78 yr during five months. Data were obtained using a Hitachi Supria 16-slice CT simulator at a regional oncology center in Morocco. CT-RT images are intended for 3D conformal radiotherapy treatment planning. Dose length product (DLP) and volumetric computed tomography dose index (CTDIvol) were evaluated by determining the 75th percentile as diagnostic reference levels for CT-RT breast cancer. LDRLs for CT-RT breast cancer have been determined in terms of DLP and CTDIvol, and they were 330.4 mGy.cm and 6.8 mGy, respectively. The DRLs were compared with other Europeans study. DRLs for this study were lower than those for the United Kingdom (UK), Croatia and Slovenia. The results of this study can be a reference for the establishment of local and national DRLs in Morocco and the optimization of CT-RT breast cancer procedures.

Radiological imaging protection: a study on imaging dose used while planning computed tomography for external radiotherapy in Japan.

Previous studies have primarily focused on quality of imaging in radiotherapy planning computed tomography (RTCT), with few investigations on imaging doses. To our knowledge, this is the first study aimed to investigate the imaging dose in RTCT to determine baseline data for establishing national diagnostic reference levels (DRLs) in Japanese institutions. A survey questionnaire was sent to domestic RT institutions between 10 October and 16 December 2021. The questionnaire items were volume computed tomography dose index (CTDIvol), dose-length product (DLP), and acquisition parameters, including use of auto exposure image control (AEC) or image-improving reconstruction option (IIRO) for brain stereotactic irradiation (brain STI), head and neck (HN) intensity-modulated radiotherapy (IMRT), lung stereotactic body radiotherapy (lung SBRT), breast-conserving radiotherapy (breast RT), and prostate IMRT protocols. Details on the use of motion-management techniques for lung SBRT were collected. Consequently, we collected 328 responses. The 75th percentiles of CTDIvol were 92, 33, 86, 23, and 32mGy and those of DLP were 2805, 1301, 2416, 930, and 1158mGy·cm for brain STI, HN IMRT, lung SBRT, breast RT, and prostate IMRT, respectively. CTDIvol and DLP values in institutions that used AEC or IIRO were lower than those without use for almost all sites. The 75th percentiles of DLP in each treatment technique for lung SBRT were 2541, 2034, 2336, and 2730mGy·cm for free breathing, breath holding, gating technique, and real-time tumor tracking technique, respectively. Our data will help in establishing DRLs for RTCT protocols, thus reducing imaging doses in Japan.

A 3-year national DRL for CT in hybrid imaging study in Kuwait health environment-impact and implementation.

Diagnostic reference levels (DRLs) for CT in PET-CT are limited, and published DRLs from other countries may not be directly applicable to the State of Kuwait (KW). The authors aimed to carry out the final phase of a 3-year study on DRLs in KW, supporting optimization and dose reduction as imaging technology advances. In this cohort study, 400 adult oncology patients from 8 PET-CT centres were included, following the same procedures as in the first (2018) and second (2020) years, in accordance with the MOH-KW Ethical Committee's recommendations. The CT dose index (CTDIvol), dose-length product (DLP), and scan length were recorded, and the median, mean, standard deviation, as well as the 75th and 25th percentiles, along with the whole-body (WB) effective dose (ED), were calculated. Comparative studies were conducted to track implementation and identify any shortfalls. In this study, half-body (HB) and WB scans accounted for 66% and 34% of the total 400 cases, respectively. The proposed local DRL practice among the 8 centres in the 2022 study exhibited a maximum variation of 25%, showing a 30% improvement over 2020. The achievable local DRL remained consistent with 2020 levels. Comparative results of the third quartile DLP (476 mGy cm) and CTDIvol (4 mGy) values for 2022 indicated lower values for the third phase (400 entries) compared to 2020, with a 1.5-fold variation in DLP. The calculated ED for WB scans ranged from 2.6 to 7.1 mSv, with mean values of 4.7 ± 1.25 mSv, using a conversion factor (k = 0.0093 mSv/mGy/cm). The 2022 proposed national diagnostic reference levels (NDRLs) for HB (469 mGy cm, 4.0 mGy) were lower than the Swiss National Data (620 mGy cm, 6.0 mGy) and France (628 mGy cm, 6.6 mGy), but slightly higher than those of the United Kingdom (400 mGy cm, 4.3 mGy), despite the Swiss having about 5000 entries, France 1000 entries, and the United Kingdom 370 HB entries. There was a 11.1% continuous improvement in NDRL for 2022 compared to 9.1% in 2020 and 13% in 2018, demonstrating a trend of enhanced optimization. The data established a trend of NDRL for WBCT (PET-CT) that can serve as a national databank for ongoing optimization. This promotes improvements in patient protection and quality care within the clinical environment of the State of Kuwait, aligning with the strategic goals of Kuwait Vision-2035.

Establishment of local diagnostic reference levels for abdomen and chest radiographies in the region of Algarve, Portugal

PurposeTo assess doses variabilities in the same abdomen and chest RX exams for adults, to check the need for dose harmonization. To calculate Diagnostic Reference Levels (DRL), mandatory in the European Union, for the Algarve district in Portugal. Our results can be a valuable reference for the Portuguese official determination of DRLs, still in progress. MethodWe considered 4,936 abdomen and 41,320 chest radiographs of adults, covering 7 health centres and 35 radiographers in Algarve. Entrance skin dose (ESD) was calculated for each radiograph and the corresponding uncertainty estimated. Mean doses per centre and per technician, and their uncertainties, were calculated to access dose variabilities. DRLs, set at the 3rd quartile of the total ESD distribution, were determined for a standard patient and for intervals of body mass index (BMI) to study their correlation with patient anatomical variations. Standard quartile errors were estimated. ResultsOur results suggest significant dispersion in applied ESDs among different centres and radiographers. Estimates of DRLs also show small fluctuations across years and an important dependence on BMI intervals. For a standard patient, they are 8.7 ± 0.1 (abdomen) and 0.44 ± 0.01 (chest), while the European DRLs are, respectively, 5.1 and 0.2 (all in mGy). ConclusionsResults suggest that there is room for dose optimization and harmonization with European DRLs, urging a national dose survey and the establishment of official national DRLs. Official DRLs in intervals of BMI would be quite beneficial, to avoid unnecessary dose exposures.

Studi Awal Evaluasi Optimisasi Paparan Medik pada CT Scan dan Radiografi Umum Berdasarkan Tingkat Panduan Diagnostik

Optimization of medical exposure seeks to keep the dose given to the patient as low as possible. In diagnostic and interventional radiology activities, optimization focuses on low doses and ensures sufficient image quality for diagnostic purposes. Implementation of medical exposure optimization can be evaluated by applying the Diagnostic Reference Level (DRL). Indonesia set DRL values for CT Scan and General Radiography in 2021. This study monitored efforts to optimize medical exposure nationally by comparing the annual dose profile with the Indonesian DRL (I-DRL) and I-DRL against the regional DRL, divided into five regions. The study was conducted from January to December 2022 using patient dose data at the Patient Dose Data Information System (Si-INTAN). The data was then analyzed to obtain a national dose profile through Quartile 3 analysis (Q3) and regional DRL values through median analysis (Q2). The analysis results show several CT Scan examinations, which are still higher than the National DRL. In addition, there are high doses for several types of examinations in the Bali and Nusa Tenggara Region for CT Scan and General Radiography. In the Kalimantan Region, there are types of CT Scan examinations that are still higher than the National DRL. Based on these results, BAPETEN needs to increase efforts to foster and encourage implementation, optimizing medical exposure nationally. Efforts that can be made include issuing optimization technical guidelines for each X-ray equipment, socialization and assistance on recording and reporting patient dose data, evaluating typical dose values, evaluating medical exposure optimization, and supervising the implementation of optimizing medical exposure through inspections. BAPETEN should collaborate with stakeholders so that the programmed efforts can be carried out effectively. Keywords: Optimization, Medical Exposure, Diagnostic Reference Level, CT Scan, General Radiography

Survei Penentuan Tingkat Panduan Diagnostik pada CT Scan Kepala dan Abdomen Non-Kontras di Rumah Sakit

Diagnostic reference level (DRL) is still low for monitoring patient doses on hospital CT Scan. The need for radiation monitoring of CT Scan patients is related to radiation protection. CT Scan have a large dose, and as CT Scan develop, it is necessary to monitor the dose of CT Scan, especially those related to DRL. The importance of DRL is related to efforts to optimize radiation protection, which must be monitored regularly so that patients receive the lowest possible dose with optimal image quality. Determination of the local DRL value from quartile 2 (Q2) and national DRL with Quartile 3 (Q3) from the average CTDI vol and total DLP recordings of non-contrast CT Scan of the head and abdomen. From the survey results, local DRL calculations and national DRL contribution or I-DRL are as follows: CT scan of the head based on Q2 and Q3 obtained CTDIvol of 63.45 mGy. Meanwhile, based on Q2, it is 913,68 mGy.cm; in Q3, the DLP is 1096,42 mGy.cm; this value is below the national standard. The CT Scan Abdomen CTDIvol examination based on Q2 obtained 8.08 mGy. and based on Q3 of 10.18 mGy. Both are below the national average of 17 mGy. DLP results based on Q2 got a result of 321.99 mGy.cm, and based on Q3 obtained a result of 419,82 mGy.cm; both values are below the standard. National standards are based on the Head of BAPETEN Decree 1211/K/V/2021. DRL that exceeds the national standard for head CT Scan requires a protocol review to obtain the lowest possible dose, but the image quality remains optimal. It is an effort to optimize radiation protection. Keywords: Diagnostic Reference Level, CT Scan, Head, Abdomen, Non-Contrast

Evaluasi Diagnostic Reference Levels (DRL) Pada Pemeriksaan Thorax PA di Pulau Jawa Berdasarkan Database DRL BAPETEN

The International Commission of Radiation Protection (ICRP) defines the diagnostic Reference Level (DRL) as a tool for optimizing patient radiation dose during radiological examinations. However, its implementation has obstacles, such as the unavailability and completeness of inspection data. Because DRL plays a role in controlling the patient's dose so that it is optimal, regular DRL evaluation is needed, especially on the island of Java. This research is a retrospective study of the results of PA chest radiography examinations in the database BAPETEN DRL between 2018-2022. PA chest radiography examination data used are examination procedure, patient position, age, body weight, exposure factors (kVp and mAs), and ESAK dose (mGy). After that, statistical analysis was carried out using IBM SPSS version 26 and Microsoft Excel with descriptive statistical analysis of the mean, median, standard deviation, 1st quartile, 2nd quartile, 3rd quartile, and minimum to maximum ratio values for the ESAK dose. Next, the 3rd quartile values of the Java island province were analyzed and compared with several Asian countries and Australia. The results of the research on the 3rd quartile radiation dose values on the island of Java with the highest to the lowest were West Java (0,31 mGy, n=1273), Yogyakarta (0,5 mGy, n=33), East Java (0,24 mGy, n=1206), Central of Java (0,22 mGy, n=725), Banten (0,20 mGy, n=2349), Jakarta (0,17 mGy, n=1870). The DRL on the island of Java is still controlled and lower than the National DRL and DRL in Asian countries and Australia. Keywords: Java Island, Diagnostic Reference Level, Thorax PA, 3rd quartile.

Approaches to Establishing National Diagnostic Reference Levels for Computed Tomography: A Systematic Review

Background: The international commission on radiation protection (ICRP) publican 135 recommends that Diagnostic Reference Levels (DRLs) should be tied to defined technical and patient parameters for the imaging task. Whereas for computed tomography (CT) examinations, DRLs are defined in terms of two established technical parameters namely, Volume-based Computed Tomography Dose Index (CTDIvol) and Dose Length Product (DLP), a debate has ensued as to whether patient size, age and weight or clinical indication should be used as patient parameters. The objective of diagnostic reference levels (DRLs) is to assist in the optimisation of radiation dose to the patients while maintaining diagnostic image quality. It is generally accepted that each country requires having national DRLs to guide the practice of radiography regarding dose optimization as a prerequisite to good radiation protection practice. Objective: This review aimed to establish commonly used approaches to establishing national diagnostic reference levels for computed tomography. Methods: A systematic literature search in databases containing leading journals in radiography, radiology and medical physics was performed aided by the use of carefully selected search terms that relate to CT and DRLs. The literature search was achieved by the use of the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) flow chart. A total of 109 studies were screened out of which 54 were excluded and 55 sought for retrieval. After further assessment for quality, 20 studies were included in this study for review. Key Findings: 95% of the studies in this review used CTDIvol and DLP as technical parameters indicating dose. 70% of the studies reviewed used patient size, age and weight while 30% used clinical indication as patient parameters. 30% of the reviewed articles did indicate that the surveys to establish NDRLs employed a retrospective approach, while 35% employed a prospective approach and 35% did ..

National UK Survey of Radiation Doses During Endovascular Aortic Interventions

PurposeEndovascular aortic repair (EAR) interventions, endovascular abdominal aortic repair (EVAR) and thoracic endovascular aortic repair (TEVAR), are associated with significant radiation exposures. We aimed to investigate the radiation doses from real-world practice and propose diagnostic reference level (DRL) for the UK.Materials and MethodsRadiation data and essential demographics were retrospectively collected from 24 vascular and interventional radiology centres in the UK for all patients undergoing EAR—standard EVAR or complex, branched/fenestrated (BEVAR/FEVAR), and TEVAR—between 2018 and 2021. The data set was further categorised according to X-ray unit type, either fixed or mobile. The proposed national DRL is the 75th percentile of the collective medians for procedure KAP (kerma area product), cumulative air kerma (CAK), fluoroscopy KAP and CAK.ResultsData from 3712 endovascular aortic procedures were collected, including 2062 cases were standard EVAR, 906 cases of BEVAR/FEVAR and 509 cases of TEVAR. The majority of endovascular procedures (3477/3712) were performed on fixed X-ray units. The proposed DRL for KAP was 162 Gy cm2, 175 Gy cm2 and 266 Gy cm2 for standard EVAR, TEVAR and BEVAR/FEVAR, respectively.ConclusionThe development of DRLs is pertinent to EAR procedures as the first step to optimise the radiation risks to patients and staff while maintaining the highest patient care and paving the way for steps to reduce radiation exposures.

Establishing national clinical diagnostic reference levels and achievable doses for CT examinations in Brazil: A prospective study

PurposeDiagnostic reference levels (DRL) and achievable doses (AD) are important tools for radiation dose optimization. Therefore, a prospective study was performed which aimed to establish a multi-parametric, clinical indication based – DRL(DRLCI) and clinical indication – AD (ADCI) for adult CT in Brazil. MethodsThe prospective study included 4787 patients (50 ± 18 years old; male:female 2041:2746) at 13 Brazilian sites that have been submitted to head, paranasal sinus, cervical spine, chest, or abdomen-pelvis CT between January and October 2021 for 13 clinical indications. The sites provided the following information: patient age, gender, weight, height, body mass index[BMI], clinical indications, scanner information(vendor, model, detector configuration), scan parameters (number of scan phases, kV, mA, pitch) and dose-related quantities (CT dose index volume- CTDIvol, dose length product- DLP). Median(AD) and 75th(DRL) percentile CTDIvol and DLP values were estimated for each body region and clinical indications. Non-normal data were analyzed with the Kruskal-Wallis test. ResultsIn majority of Brazilian sites, body region and clinical indications based DRLs were at or lower than the corresponding DRLs in the US and higher than Europe. Although radiation doses varied significantly for patients in different body mass index groups (p < 0.001), within each body region, there were no differences in radiation doses for different clinical indications (p > 0.1). Radiation doses for 7/13 clinical indications were higher using iterative reconstruction technique than for the filtered back projection. ConclusionsThere was substantial variation in Brazil DRLCI across different institutions with higher doses compared to the European standards. There was also a lack of clinical indication-based protocol and dose optimization based on different clinical indications for the same body region.

Average Glandular Dose (AGD) and Radiation Dose Optimization in Screen-Film and Digital X-ray Mammography

We determined the average glandular dose (AGD) from the craniocaudally (CC) and mediolateral oblique (MLO) views of 496 breasts (247 women) at eight clinics in Sudan. The incident air kerma from the X-ray tube output values and the typical patient-specific breast exposure factors were measured. The AGD values were inferred from the measured incident air kerma and breast-specific dose-conversion coefficients. The AGD per CC and MLO projection and per woman ranged from 0.56 to 2.89 mGy (average: 1.36), 0.48 to 2.08 mGy (average: 1.19), and 2.08 to 9.94 mGy (average: 5.10). The proposed national diagnostic reference levels (mGy) for digital mammography are 1.8 and 1.6 mGy for CC and MLO projection, respectively. Establishing the proposed diagnostic reference levels is an essential step in ensuring patient protection from radiation and will help promote dose optimization for X-ray mammography at the national level and beyond. These results provide important baseline data that can be used to formulate national diagnostic reference levels.

The radiation dose from whole body hybrid imaging (PET–CT) procedures in Sri Lanka: The initial approach towards establishing national diagnostic reference level

Positron emission tomography-Computed tomography (PET–CT) is a hybrid imaging modality that is increasingly used in the diagnosis and staging of cancer. However, due to its hybrid nature, PET–CT is associated with a high radiation dose, which is a concern for patient safety. The aim of this study is to assess the radiation dose from both components of PET and CT to establish diagnostic reference levels (DRLs) that can be used as a tool for dose optimization. This study presents the results of the initial attempt to establish DRLs for body PET–CT procedures among adults and children in Sri Lanka.Data on the injected activity (MBq) and CT radiation dose, volume CT dose index (CTDIvol) and dose length product (DLP) were collected from three PET–CT centers in Sri Lanka and the institutional diagnostic reference level (IDRL) has been established using the median dose distribution for each center and procedure. The median of the individual IDRLs was presented as the national diagnostic reference level (NDRL). Additionally, the mean, standard deviation, 25th, and 75th percentiles of the pooled dose distribution have been presented with and without weight restrictions for adults, as well as for several age and weight bins for pediatrics.The average injected activity of standard adult patients was 187 ± 37 MBq while for pediatric patients aged 1 to 15 years, it ranged between 105 ± 22 and 139 ± 43 MBq. The average CT dose based on CTDIvol and DLP for a standard adult were 3.81 ± 0.86 mGy and 668 ± 140 mGy.cm. The average CTDIvol and DLP ranged between 2.05 ± 0.76–3.65 ± 1.59 and 195 ± 50–411 ± 188 for pediatric patients. The NDRL based on injected activity for adults and pediatric was 198.3 203.3 MBq and 127.7 MBq. The levels of injected activity for adult patients were found to be lower than those published internationally. However, procedures involving both PET and CT in pediatric patients require dose optimization.The present study proposed IDRL and NDRL values for body PET–CT procedures in Sri Lanka. The findings indicate that these values can serve as an effective guide for achieving further optimization in dose, particularly in procedures involving both PET and CT in pediatric patients.

OPTIMISASI DOSIS DAN KUALITAS CITRA PADA PEMERIKSAAN PULMONARY ARTERY CATHETER (PAC) DAN PERCUTANEUS CORONARY INTERVENTION (PCI) SEBAGAI UPAYA PROTEKSI RADIASI PASIEN DI CATHLAB RSUP ADAM MALIK MEDAN

The radiation exposure a patient receives during diagnosis and treatment cannot be fully avoided. However, it is crucial to optimize the radiation dose to ensure it is only as much as needed. The purpose of this study is to minimize the patient's radiation exposure during interventions and produce optimal image quality. To accomplish this, dose optimization and image quality were evaluated during PAC and PCI procedures in the Cathlab room at Adam Malik Hospital using Philips Allura Xper FD20. The study was retrospective, using patient dose audits from January 2020 to February 2023, with 250 PACs and 139 PCI mature patients. The median dose value (Q2) was compared to the National diagnostic reference level (NDRL) third quartile (Q3) value to determine optimal patient dose levels. We used a 28 cm PMMA phantom and a 2 cm imaging quality in-house phantom to represent the patient and a solid-state detector to measure surface dose. Medical physicists, radiographers, cardiologists, and nurses worked together in optimization cycles to ensure dose levels were kept to a minimum. Image quality was assessed by calculating the signal difference-to-noise ratio (SDNR), and images were recorded in DICOM format and analyzed using Image J software. Entrance Surface Air Kerma (ESAK) values were recorded to calculate Figure of Merit (FOM) values for each change in physical parameters. The study showed that the distance between the image detector and the object significantly affects the patient's dose. A distance of 14 cm resulted in a higher dose than a distance of 2 cm. The SDNR value varied with the object image distance (OID) factor, and increasing the object's distance to the image detector did not increase the SDNR value. Setting the OID spacing to a minimum is recommended for PAC and PCI procedures to minimize the patient's radiation exposure. The FOM values were affected by both the ESAK and SDNR values. Keywords: Dose Optimization, Image Quality, objek to image distance (OID), Pulmonary Artery Catheter, Percutaneous Coronary Intervention, Cathlab.

PENENTUAN TIPIKAL DOSIS PADA PEMERIKSAAN RADIOGRAFI THORAKS PA BERDASARKAN KURVA REFERENSI-DRL MENGGUNAKAN DATABASE SI-INTAN BAPETEN

Consideration of patient weight as an essential indicator in optimization efforts. This is because the radiation dose varies not only for age groups but is accompanied by changes in body weight. This research method uses a retrospective study of PA chest radiography examination results in the BAPETEN DRL database between 2018-2022. PA chest radiography examination data used: examination projection, body weight, age, source image distance, exposure factor consisting of kV and mAs, and entrance surface air kerma (ESAK) dose. Data were analyzed to create a DRL-reference curve by grouping body weight from 30-101 kg with a range of 5 kg. The first stage of data fitting is to determine the relationship between body weight (kg) and radiation dose (mGy). The second stage creates a DRL reference curve using the exponential function. Next, determine the DRL value for each weight group with the 25th percentile, 50th percentile, and 75th percentile values. Continue by determining descriptive statistical values: average, standard deviation, and range. As well as comparing the 75th percentile typical dose value between the Jakarta DRL Local value and the Indonesian National DRL value. As a result of the research, a DRL reference curve for body weight groups against radiation dose was created. DRL reference curves can be compared according to further research needs or as an optimization effort. The 75th percentile DRL reference curve for the Jakarta DRL Local data is higher than the Indonesian DRL National data. Therefore, collaboration between all parties is needed to optimize radiography procedures to control the Jakarta DRL-reference curve. Data limitations are also an important factor that can cause the shape of the exponential curve to change. Keywords: DRL-reference curve, diagnostic reference level, Thorax PA.

Assessment of radiographers' knowledge about radiation doses and DRLs in computed tomography departments in Jeddah, Saudi Arabia: A cross-sectional study

ObjectiveTo assess radiographers' understanding of radiation safety considering the newly approved national diagnostic reference levels (DRLs) as an optimization tool for radiation dose. MethodsA cross-sectional study was conducted in Saudi Arabia among radiographers working at local hospitals in Jeddah city from February to March 2022. The survey comprised of 22 questions involving demographic information; and general information related to radiation dose; CTDIvol and DRLs. Data were analyzed using IBM SPSS Statistics version 26. Chi-square test was used to compare demographic groups regarding their distribution of responses with 0.05 as the level of significance. ResultsA total of 169 radiographers participated in the study (39 % females, 60 % males). Most of the participants (91 %) were aware of the description of the ALARA principle. It was noted that (47 %) of the participants indicated that the routine scanning protocols are designed by the radiologists. The majority of them (78 %) were confident to manipulate the CT scanning parameters properly. In addition, half of the participants (53 %) were aware of the CTDIvol and DLP. Unexpectedly, none of the demographic variables were significantly associated with the radiographers’ knowledge about radiation dose, p-values are > 0.05. ConclusionAlthough radiographers demonstrated good knowledge of radiation protection, limited awareness of DRLs was noted among radiographers and lack of implementing and optimizing the local dose of the DRLs in this study. Therefore, education and training for healthcare professionals including radiographers are necessary to enhance clinical practical performance in radiology departments.

Assessment of Radiation Dose and Phantom Skin Dose in Transarterial Chemoembolization in a Single Center with 2 Digital Subtraction Angiography Units

Objectives: This study aimed to assess and compare the radiation dose and phantom skin dose in transarterial chemoembolization (TACE) of two digital subtraction angiography (DSA) units (unit A: Philips Allura Xper FD20, unit B: Artis zee biplane)Material and Methods: The dose area product (DAP), reference air kerma (RAK), number of images (NI) and fluoroscopy time (FT) of 240 cases (120 cases/DSA unit) were retrospectively reviewed and collected. To assess skin dose, 28 nanoDot optically stimulated luminescence dosimeters (OSLDs) were placed on the phantom’s back and the TACE procedure was performed with 2 DSA units.Results: The median DAP, RAK, NI, and FT of unit A were 200.49 Gy·cm2, 379.84 mGy, 115 images, and 9.04 minutes, while for unit B were 109.74 Gy·cm2, 276.55 mGy, 121 images, and 10.19 minutes, respectively. Significant differences were observed in DAP, RAK, and FT. The RAK of all patients was less than 2 Gy. The phantom skin dose obtained from unit B was significantly lower than that of unit A in all positions. The peak skin doses of the phantom studies from both units were 973.15 and 658.66 mGy, respectively.Conclusion: The median DAP of the unit A DSA was higher than the national diagnostic reference levels (DRLs). The TACE procedure from both units is safe from skin reaction. To benefit patients, the planning of a dose optimization process of unit A DSA and management of TACE cases using the existing DSA machine must be considered.

Towards the establishment of national diagnostic reference levels for chest x-ray examinations in Sri Lanka: a multi-centric study

The establishment of diagnostic reference levels (DRLs) is an effective tool for optimising radiation doses delivered to patients during medical imaging procedures. This study aimed to compare the institutional DRLs (IDRLs) and propose a multi-centric diagnostic reference level (MCDRL) for chest x-ray examinations in adult patients in Sri Lanka. A prospective cross-sectional study was conducted with 1091 adult patients across six major tertiary care hospitals. Data on patient characteristics, such as age, sex, weight, and body mass index, and exposure parameters, such as tube voltage (kVp) and the product of tube current and exposure time (mAs), were collected. Patient doses were measured in terms of kerma-area product (PKA) using a PKA meter mounted on the collimator of the x-ray tube. IDRLs were computed for each hospital according to the International Commission on Radiological Protection guidelines, and the 75th percentile PKA was used to propose the MCDRL. The relationship between patient weight and exposure parameters was examined using Spearman’s rank correlation to investigate the radiographic practice among hospitals. Results showed that IDRLs varied from 0.10 to 0.26 Gy cm2. The proposed MCDRL was 0.23 Gy cm2, substantially higher than the recently published DRLs from other countries. The median kVp ranged from 95 to 104, while mAs ranged from 2.5 to 5.6. Large variations in the PKA and exposure parameters were observed within and among hospitals. The elevated PKA values observed in this study were mostly due to the use of high mAs in clinical practice. The weak correlation observed between patient weight and exposure parameters suggests the need to standardise examination protocols concerning patient size. The observed dose variations demonstrate the need for the establishment of national DRLs. Until then, the proposed MCDRL can be considered as the benchmark dose level for chest x-ray examinations in Sri Lanka.