•Large-scale data collection of CT scanning parameters from PACS, DMS, RIS in Germany.•Data on 7746 CT series allow fine-grained characterization of parameter distributions.•Decreasing trend in doses ...compared to earlier time period and to current national DRL.•Documentation quality at scan time crucial for automated data collection and analysis.
Accumulating evidence from epidemiological studies that pediatric computed tomography (CT) examinations can be associated with a small but non-zero excess risk for developing leukemia or brain tumor highlights the need to optimize doses of pediatric CT procedures. Mandatory dose reference levels (DRL) can support reduction of collective dose from CT imaging. Regular surveys of applied dose-related parameters are instrumental to decide when technological advances and optimized protocol design allow lower doses without sacrificing image quality. Our aim was to collect dosimetric data to support adapting current DRL to changing clinical practice.
Dosimetric data and technical scan parameters from common pediatric CT examinations were retrospectively collected directly from Picture Archiving and Communication Systems (PACS), Dose Management Systems (DMS), and Radiological Information Systems (RIS).
We collected data from 17 institutions on 7746 CT series from the years 2016 to 2018 from examinations of the head, thorax, abdomen, cervical spine, temporal bone, paranasal sinuses and knee in patients below 18 years of age. Most of the age-stratified parameter distributions were lower than distributions from previously-analyzed data from before 2010. Most of the third quartiles were lower than German DRL at the time of the survey.
Directly interfacing PACS, DMS, and RIS installations allows large-scale data collection but relies on high data-quality at the documentation stage. Data should be validated by expert knowledge or guided questionnaires. Observed clinical practice in pediatric CT imaging suggests lowering some DRL in Germany is reasonable.
Ob jectives
The European Society of Radiology identified 10 common indications for computed tomography (CT) as part of the European Study on Clinical Diagnostic Reference Levels (DRLs, EUCLID), to ...help standardize radiation doses. The objective of this study is to generate DRLs and median doses for these indications using data from the UCSF CT International Dose Registry.
Methods
Standardized data on 3.7 million CTs in adults were collected between 2016 and 2019 from 161 institutions across seven countries (United States of America (US), Switzerland, Netherlands, Germany, UK, Israel, Japan). DRLs (75th percentile) and median doses for volumetric CT-dose index (CTDI
vol
) and dose-length product (DLP) were assessed for each EUCLID category (chronic sinusitis, stroke, cervical spine trauma, coronary calcium scoring, lung cancer, pulmonary embolism, coronary CT angiography, hepatocellular carcinoma (HCC), colic/abdominal pain, appendicitis), and US radiation doses were compared with European.
Results
The number of CT scans within EUCLID categories ranged from 8,933 (HCC) to over 1.2 million (stroke). There was greater variation in dose between categories than within categories (
p
< .001), and doses were significantly different between categories within anatomic areas. DRLs and median doses were assessed for all categories. DRLs were higher in the US for 9 of the 10 indications (except chronic sinusitis) than in Europe but with a significantly higher sample size in the US.
Conclusions
DRLs for CTDI
vol
and DLP for EUCLID clinical indications from diverse organizations were established and can contribute to dose optimization. These values were usually significantly higher in the US than in Europe.
Key Points
•
Registry data were used to create benchmarks for 10 common indications for CT identified by the European Society of Radiology.
•
Observed US radiation doses were higher than European for 9 of 10 indications (except chronic sinusitis).
•
The presented diagnostic reference levels and median doses highlight potentially unnecessary variation in radiation dose.
Saudi National diagnostic reference levels (NDRLs) Alaboudi, Nasser; Almutairi, Abdulrahman; Almosabahi, Abdulaziz ...
Radiation physics and chemistry (Oxford, England : 1993),
20/May , Letnik:
218
Journal Article
Recenzirano
Saudi Food and Drug Authority (SFDA) has led the first governmental initiative to establish Saudi National Diagnostic Reference Levels (NDRLs) for various imaging modalities. NDRLs provide benchmarks ...for radiation dose levels in medical imaging procedures, ensuring that these doses are optimized and kept as low as reasonably achievable while maintaining diagnostic image quality.
The NDRLs established in adherence to international guidelines for the common routine examinations, which include Computed Tomography (CT) (adults and pediatrics) that cover 54 hospitals, General X-ray that cover 22 hospitals, and Mammography that cover 7 hospitals across the Kingdom of Saudi Arabia (KSA), including a total of 29,672 cases.
The established NDRLs encompass a range of doses for various imaging modalities ensuring diagnostic efficacy while maintaining safety. The dose ranges for adult CT procedures were as follows: Head CT showed a CTDIvol of 24–95 mGy and a DLP of 495–1435 mGy-cm; Abdomen & Pelvis CT had a CTDIvol of 5–17 mGy and a DLP of 269–996 mGy-cm; Chest CT reported a CTDIvol of 6–16 mGy and a DLP of 160–578 mGy-cm. For pediatric CT, the Head CT for ages 0–5 years had a CTDIvol of 15–32 mGy and a DLP of 289–652 mGy-cm, while for ages 6–15, the CTDIvol was 23–44 mGy and the DLP was 389–866 mGy-cm. The abdomen X-ray DAP ranged from 0.04 to 6.71 (Gy.cm2), while Chest X-ray DAP ranged from 0.05 to 0.9 (Gy.cm2), and the Mammogram 2D MGD for a thickness of 40–53 cm was between 0.92 and 1.64 mGy.
The establishment of the NDRLs aligns with the strategic objectives of the SFDA aiming to ensure safety, efficacy and performance of medical devices. This initiative addresses a significant advancement in the regulatory framework for medical imaging in the kingdom and setting a procedure for future quality assurance measures.
•The SFDA leads the first governmental initiative to establish NDRLs.•This marks a proactive approach by the SFDA towards dose optimization.•The NDRLs were established for various imaging modalities (CT, X-ray, and Mammography).•The NDRLs were compared to several countries where NDRLs are well established.•The NDRLs will be reviewed periodically to align with best practices.
This study aims to report the findings of Jordanian national diagnostic reference level (NDRL) survey for fluorodeoxyglucose (
F-FDG) and local diagnostic reference level (LDRL) of computed ...tomography (CT) used for attenuation correction and anatomical localisation (AC-AL); and AC and diagnostic CT (AC-DX) within the context of whole-body WB and half-body HB adult oncology PET/CT scanning. Two-structured questionnaires were prepared to gather the necessary information: dosimetry data, patient demographics, equipment specification, and acquisition protocols for identified
F-FDG PET/CT procedures. The NDRL and achievable dose were reported based on the 75th and 50th percentiles for
F-FDG administered activity (AA), respectively. The LDRL was reported based on the 50th percentile for (CTDI
) and (DLP). Data from 562 patients from four Jordanian PET/CT centres were collected. The survey revealed that Jordanian NDRL for AA (303 MBq) was within the acceptable range compared to the published-peer NDRL data (240-590 MBq). However, the
F-FDG AA varied across the participated PET/CT centres. The reported LDRL CTDI
and DLP of CT used for (AC-AL) was 4.3 mGy and 459.3 mGy.cm for HB CT scan range, and 4.1 mGy and 659.9 mGy.cm for WB CT scans. The reported LDRL for CTDI
and DLP for HB CT was higher when compared with the United Kingdom (3.2 mGy and 310 mGy.cm). Concurrently, in the context of WB CT, the reported values (i.e. CTDIvol and DLP) were also higher than both Kuwait (3.6 mGy and 659 mGy.cm) and Slovenia (3.6 mGy and 676 mGy.cm). The reported HB CT(AC-DX) was higher than Nordic, New Zealand and Swiss NDRLs and for WB (AC-DX) CT it was higher than Swiss NDRLs. This study reported the first Jordanian NDRL for
F-FDG and LDRL for HB and WB CT associated with
F-FDG PET/CT scans. This data is useful for Jordanian PET/CT centres to compare their LDRL to the suggested DRLs and utilise it in the process of optimising CT radiation doses.
To investigate retrospective classification of adult patients into small, average, and large based on effective diameter (EDia) from localizer image of computed tomography (CT) scans and to develop ...regional diagnostic reference levels (DRLs) and achievable doses (AD).
The patients falling within the mean ± standard deviation (SD) of EDia were classified as average; those below this range as small and above as large. The CTDIvol,dose-length-product (DLP) and size-specific dose estimates (SSDE) of all adult patients undergoing CT examinations in 8 CT facilities for 11 months (Dec. 2019 - Oct. 2020) were evaluated. The 75th and 50th percentile values were compared with national and international values.
Of the total of 69,434 CT examinations, nearly 80% fell within average size. The 75th percentile values of CTDIvol and DLP for small patients for abdomen-pelvic exams were nearly half of average sized patients. Similarly, the 75th percentile values for large patients were nearly double. Similar findings were not found for chest exams. Analysis of image quality and dose factors such as noise, mean axial length, slice thickness, mean number of sequences, use of iterative reconstruction and tube current modulation (TCM) resulted in identification of opportunities for improvement and optimization of different CT facilities.
DRLs for adult patients were found to vary widely with patient size and thus establishing DRLs only for standard sized patient is not adequate. Simplified and intuitive methods for size classification was shown to provide meaningful information for optimization for patients outside the standard size adult.
The objective of this study is to establish clinical-indication based Diagnostic Reference Levels (DRLs) for the Computed Tomography (CT) examinations of Head, Abdomen & Pelvis + Contrast, and Kidney ...Ureter Bladder (KUB). Further, is to investigate the cases that register high-end doses to enable dose optimization.
Dose length product total (tDLPs) and scan acquisition parameters of a total of 715 patients who underwent CT Head, CT Abdomen & Pelvis + Contrast, and CT KUB studies were obtained and retrospectively examined. An electronic patient radiation dose monitoring system DOSE-TQM linked with the existing PACS was used to randomly generate patient dose information. Patient’s demographics, clinical indications and scan acquisitions were also collected. ANOVA and Tukey’s multiple comparison tests were used to check statistical differences between tDLPs per clinical indications.
The data exhibited 341 CT Head, 109 patients for CT Abdomen & Pelvis + Contrast, and 265 CT KUB examinations. The DRLs proposed using total DLP (mGy.cm) for clinical indications; abdominal pain for both CT Abdomen & Pelvis + Contrast and CT KUB (441 and 311 mGy.cm, respectively), appendicitis /acute appendicitis (484 mGy.cm), head trauma (544 mGy.cm), stroke (544 mGy.cm) and renal colic (308 mGy.cm). These values were concluded to be below or in close proximity with the total DLP based indication reported internationally. Patient weight is a significant dose contributor.
DLP differences exists not only between the same anatomical based CT studies but also across the same clinical indications. DLPs based on clinical indications provide a tool for CT dose optimisation that is better adapted to clinical practices and to the variability of patient’s morphology.
Objectives
To propose national diagnostic reference levels (DRLs) for interventional radiology and to evaluate the impact of the procedural complexity on patient doses.
Methods
Eight interventional ...radiology units from Spanish hospitals were involved in this project. The participants agreed to undergo common quality control procedures for X-ray systems. Kerma area product (KAP) was collected from a sample of 1,649 procedures. A consensus document established the criteria to evaluate the complexity of seven types of procedures. DRLs were set as the 3rd quartile of KAP values.
Results
The KAP (3rd quartile) in Gy cm
2
for the procedures included in the survey were: lower extremity arteriography (n = 784) 78; renal arteriography (n = 37) 107; transjugular hepatic biopsies (THB) (n = 30) 45; biliary drainage (BD) (n = 314) 30; uterine fibroid embolization (UFE) (n = 56) 214; colon endoprostheses (CE) (n = 31) 169; hepatic chemoembolization (HC) (n = 269) 303; femoropopliteal revascularization (FR) (n = 62) 119; and iliac stent (n = 66) 170. The complexity involved the increases in the following KAP factors from simple to complex procedures: THB x4; BD x13; UFE x3; CE x3; HC x5; FR x5 and IS x4.
Conclusions
The evaluation of the procedure complexity in patient doses will allow the proper use of DRLs for the optimization of interventional radiology.
Key Points
•
National DRLs for interventional procedures have been proposed given level of complexity
•
For clinical audits, the level of complexity should be taken into account.
•
An evaluation of the complexity levels of the procedure should be made.
Objectives
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.
Methods
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.
Results
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.
Conclusions
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.
Clinical relevance statement
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.
Key Points
•
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.
CT is still not a low‐dose imaging modality Rehani, Madan M.; Szczykutowicz, Timothy P.; Zaidi, Habib
Medical physics (Lancaster),
February 2020, 2020-02-00, Letnik:
47, Številka:
2
Journal Article
Concerns regarding the consequences of ionizing radiation (IR) have been increasing in the field of interventional cardiology (IC). There is little information on reported national and local ...radiation diagnostic reference levels (DRLs) in catheterization laboratories in Portugal. This study was designed to assess the IR dose exposure during complex percutaneous coronary intervention (PCI), and to set the respective DRLs and future achievable doses (ADs).
This was a retrospective cohort study which took place between 2019 and 2020, including patients who underwent complex PCI. Complex PCI was defined as all procedures that encompass treatment of chronic total occlusions (CTO) or left main coronary artery. DRLs were defined as the 75th percentile of the distribution of the median values of air kerma area product (PKA) and cumulative air kerma (Ka,r). ADs were set at the 50th percentile of the study dose distribution. Multivariate analysis was performed using linear regression to identify predictors significantly associated with radiation dose (Ka,r).
A total of 242 patients were included in the analysis. Most patients underwent a CTO procedure (146, 60.3%). Patients were aged 67.9±11.2 years and mostly male (81.4%). DRLs were set in Ka,r (3012 mGy) and PKA (162 Gy cm2) for complex PCI. ADs were also set in Ka,r (1917 mGy) and PKA (101 Gy cm2). Independent predictors of Ka,r with a positive correlation were PKA (0.893, p<0.001), fluoroscopy time (0.520, p<0.001) and PCI time (0.521, p<0.001).
This study reports the results of IR in complex PCI. DRLs were set for IR dose exposure measured in Ka,r (3012 mGy) and PKA (162 Gy cm2). ADs, values to be achieved in future assessment, were set to Ka,r (1917 mGy) and PKA (101 Gy cm2).
A preocupação com as consequências da radiação ionizante (IR) aumentou entre a cardiologia de intervenção (IC). Ainda assim, os dados reportados sobre os níveis de referência de dose de radiação (DRLs) são escassos nos laboratórios de hemodinâmica em Portugal. Este estudo foi concebido para aceder às doses de radiação durante a intervenção coronária percutânea complexa (PCI) e para definir os respetivos DRLs e futuras dose a alcançar (ADs).
Estudo retrospetivo (2019 e 2020) de doentes submetidos a PCI complexa. Definiu-se PCI complexa como os procedimentos que englobaram tratamento de oclusões totais crónicas (CTO) e lesões do tronco comum. Os DRLs são definidos como o percentil 75th da distribuição dos valores medianos do air kerma area product (PKA) e do cumulative air kerma (Ka,r). As ADs foram fixadas no percentil 50th da distribuição da dose de IR do estudo. A análise multivariada foi realizada utilizando a regressão linear para identificar os preditores significativamente associados à dose de radiação (Ka,r).
Análise com 242 doentes. A maioria dos pacientes realizou um procedimento de CTO (146, 60,3%). Os DRLs foram definidos em Ka,r (3012 mGy) e PKA (163 Gy.Cm2) para a PCI complexa. As ADs foram definidas em Ka,r (1917 mGy) e PKA (101 Gy.Cm2). Os preditores independentes de Ka,r com uma correlação positiva foram PKA (0,893, p < 0,001), tempo de fluoroscopia (0,520, p < 0,001) e tempo de PCI (0,521, p < 0,001).
Foram definidos em PCI complexa DRLs para exposição à dose de radiação medida em Ka,r (3012 mGy) e PKA (162 Gy.Cm2). As ADs, valores a atingir em futura avaliação, foram definidas em Ka,r (1917 mGy) e PKA (101 Gy.Cm2).
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