Challenges in Occupational Dosimetry for Interventional Radiologists.

This review presents the challenges met by interventional radiologists in occupational dosimetry. The issues mentioned are derived from the recommendations of the International Commission on Radiological Protection, the CIRSE guidelines on "Occupational radiation protection in interventional radiology" and the requirements of the European directive on Basic Safety Standards. The criteria for a proper use of personal dosimeters and the need to introduce optimization actions in some cases are set out in this review. The pros and cons of the electronic real-time dosimeters are outlined and the potential pitfalls associated with the use of personal dosimeters summarized. The electronic dosimeters, together with the appropriate software, allow an active optimization of the interventional procedures.

Diagnostic reference levels and complexity indices in interventional radiology: a national programme.

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 cm2 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.

Benefits of an automatic patient dose registry system for interventional radiology and cardiology at five hospitals of the Madrid area.

The purpose of this article is to present the results of connecting the interventional radiology and cardiology laboratories of five university hospitals to a unique server using an automatic patient dose registry system (Dose On Line for Interventional Radiology, DOLIR) developed in-house, and to evaluate its feasibility more than a year after its introduction. The system receives and stores demographic and dosimetric parameters included in the MPPS DICOM objects sent by the modalities to a database. A web service provides a graphical interface to analyse the information received. During 2013, the system processed 10 788 procedures (6874 cardiac, 2906 vascular and 1008 neuro interventional). The percentages of patients requiring clinical follow-up due to potential tissue reactions before and after the use of DOLIR are presented. The system allowed users to verify in real-time, if diagnostic (or interventional) reference levels are fulfilled.

Automatic patient dose registry and clinical audit on line for mammography.

The use of automatic registry systems for patient dose in digital mammography allows clinical audit and patient dose analysis of the whole sample of individual mammography exposures while fulfilling the requirements of the European Directives and other international recommendations. Further parameters associated with radiation exposure (tube voltage, X-ray tube output and HVL values for different kVp and target/filter combinations, breast compression, etc.) should be periodically verified and used to evaluate patient doses. This study presents an experience in routine clinical practice for mammography using automatic systems.

Niveles de referencia de dosis en radiología intervencionista / Diagnostic reference levels in interventional radiology

Se describe el concepto de los niveles de referencia de dosis para diagnóstico («diagnostic reference levels») propuestos por la Comisión Internacional de Protección Radiológica (ICRP) como ayuda para la aplicación del criterio de optimización en radiodiagnóstico y en procedimientos intervencionistas. Dichos niveles se establecen habitualmente como el tercer cuartil de las distribuciones de dosis a pacientes en una muestra amplia de centros y se supone que son valores representativos de buena práctica desde un punto de vista de la protección del paciente. Durante su determinación, se debe evaluar también la calidad de las imágenes para asegurar que es suficiente para el diagnóstico. Cuando los valores de las dosis a los pacientes resultan ser sistemáticamente mayores o mucho más bajos que los valores de referencia, procede realizar una investigación para la posible aplicación de medidas correctoras. Las normativas europea y española de protección del paciente obligan a utilizar los valores de referencia en los programas de calidad. Para los procedimientos intervencionistas se suelen utilizar como valores de referencia el producto dosis área (o producto kerma área) junto con el tiempo de fluoroscopia y el número total de imágenes adquiridas. En los equipos más modernos, se puede también utilizar el valor de la dosis acumulada a la entrada del paciente para optimizar la distribución de la dosis en la piel. La ICRP recomienda que se tenga en cuenta la complejidad de los procedimientos intervencionistas cuando se establecen los valores de referencia. Los servicios de diagnóstico por imagen dispondrán en el futuro de sistemas automáticos de gestión de datos dosimétricos a pacientes que permitirán la auditoría continua de las dosis y recibir alertas sobre procedimientos individuales que puedan registrar dosis varias veces por encima de los valores de referencia. Se presentan también los aspectos que requieren aclaraciones para el mejor aprovechamiento de los niveles de referencia en intervencionismo (AU)

This article discusses the diagnostic reference levels for radiation exposure proposed by the International Commission on Radiological Protection (ICRP) to facilitate the application of the optimization criteria in diagnostic imaging and interventional procedures. These levels are normally established as the third quartile of the dose distributions to patients in an ample sample of centers and are supposed to be representative of good practice regarding patient exposure. In determining these levels, it is important to evaluate image quality as well to ensure that it is sufficient for diagnostic purposes. When the values for the dose received by patients are systematically higher or much lower than the reference levels, an investigation should determine whether corrective measures need to be applied. The European and Spanish regulations require the use of these reference values in quality assurance programs. For interventional procedures, the dose area product (or kerma area product) values are usually used as reference values together with the time under fluoroscopy and the total number of images acquired. The most modern imaging devices allow the value of the accumulated dose at the entrance to the patient to be calculated to optimize the distribution of the dose on the skin. The ICRP recommends that the complexity of interventional procedures be taken into account when establishing reference levels. In the future, diagnostic imaging departments will have automatic systems to manage patient dosimetric data; these systems will enable continuous dosage auditing and alerts about individual procedures that might involve doses several times above the reference values. This article also discusses aspects that need to be clarified to take better advantage of the reference levels in interventional procedures (AU)

[Diagnostic reference levels in interventional radiology]. / Niveles de referencia de dosis en radiología intervencionista.

This article discusses the diagnostic reference levels for radiation exposure proposed by the International Commission on Radiological Protection (ICRP) to facilitate the application of the optimization criteria in diagnostic imaging and interventional procedures. These levels are normally established as the third quartile of the dose distributions to patients in an ample sample of centers and are supposed to be representative of good practice regarding patient exposure. In determining these levels, it is important to evaluate image quality as well to ensure that it is sufficient for diagnostic purposes. When the values for the dose received by patients are systematically higher or much lower than the reference levels, an investigation should determine whether corrective measures need to be applied. The European and Spanish regulations require the use of these reference values in quality assurance programs. For interventional procedures, the dose area product (or kerma area product) values are usually used as reference values together with the time under fluoroscopy and the total number of images acquired. The most modern imaging devices allow the value of the accumulated dose at the entrance to the patient to be calculated to optimize the distribution of the dose on the skin. The ICRP recommends that the complexity of interventional procedures be taken into account when establishing reference levels. In the future, diagnostic imaging departments will have automatic systems to manage patient dosimetric data; these systems will enable continuous dosage auditing and alerts about individual procedures that might involve doses several times above the reference values. This article also discusses aspects that need to be clarified to take better advantage of the reference levels in interventional procedures.

Spanish experience in education and training in radiation protection in medicine.

In most of its publications, the International Commission on Radiological Protection has highlighted the importance of education and training in radiation protection (RP) for medical exposures. Spain, like other Member States of the European Union, has implemented the Directive and the Guidelines in the medical area. The purpose of this paper is to present the Spanish experience in RP education and training in medicine, the different objectives established according to professional levels, existing regulations and feedback obtained from various RP actions.

Optimising the use of computed radiography in pediatric chest imaging.

The objective of this study was to analyze image quality of chest examinations in pediatric patients using computed radiography (CR) obtained with a wide range of doses to suggest the appropriate parameters for optimal image quality. A sample of 240 chest images in four age ranges was randomly selected from the examinations performed during 2004. Images were obtained using a CR system and were evaluated independently by three radiologists. Each image was scored using criteria proposed by the European Guidelines on Quality Criteria in Pediatrics. Mean global scoring and scoring of individual criteria more sensitive to noise were used to evaluate image quality. Agfa dose level (DL) was in the range 1.20 to 2.85. It was found that there was not significant correlation (R < 0.5) between image quality and DL for any of the age ranges for either global score or for individual criteria more related to noise. The mean value of DL was in the ranges 1.9-2.1 for the four age bands. From this study, a DL value of 1.6 is proposed for pediatric CR chest imaging. This could yield a reduction of approximately a factor of 2.5 in mean patient entrance surface doses.

A survey of patient dose and clinical factors in a full-field digital mammography system.

In this work, we analyse the dose to 5034 patients (20 137 images) who underwent mammographic examinations with a full-field digital mammography (FFDM) system over a 2-y period. The information relevant to this study has been extracted from the image Digital Imaging and Communications in Medicine (DICOM) headers. Entrance surface air-kerma (ESAK) without backscatter and average glandular dose (AGD) were estimated following the methodology proposed in the European Protocol on Dosimetry in Mammography. Mean values for patient age and compressed breast thickness were 56 +/- 11 y and 52 +/- 13 mm, respectively. The mean ESAK value was 8.1 mGy and the mean AGD was 1.9 mGy. In addition, the dose values from both FFDM and screening-film mammographic (SFM) examinations were compared. The third quartile (TQ) of the ESAK values delivered by the FFDM system was 33% lower and 32% higher than the TQ for SFM with slow and fast screen/film receptors. Differences between dose values for cranio-caudal (CC) and medio-lateral oblique (MLO) images (about 27% for SFM) decreased to 11% for FFDM.