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Objectives: The diagnostic reference level (DRL) is a useful tool for the optimisation of medical exposures. Thus, a Working Party coordinated by the Italian National Institute of Health and the National Workers Compensation Authority has been formed to provide Italian DRLs, for both diagnostic and interventional procedures, to be used as appropriate for the implementation of the 2013/59 European Directive into the national regulation., Materials and Methods: The multidisciplinary Working Party was formed by professionals involved in diagnostic and interventional radiology medical exposures and started from a critical revision of both the literature and the results of previous Italian surveys. The procedures were divided into five sections for adult (projection radiography, mammography, diagnostic fluoroscopy, CT and interventional radiology) and two sections for paediatric patients (projection radiography and CT). The provided DRL values have been identified for "normal" adult patients and for age-classes of paediatric patients., Results: Some of the DRL values provided by the Working Party are reported in this study as an example, divided by adult/paediatric patients, radiological technique and examination: specifically, DRLs for new radiological practices and new dose quantities as DRLs metric were introduced. The median value (rather than the mean) for each procedure, derived from a sample of patients, has to be compared with the corresponding DRL value, and dosimetric data related to a minimum number of patients should be collected for each examination., Conclusions: The approach to the definition and use of DRLs through guidelines of national Authorities in collaboration with scientific Associations should simplify the periodical updating and could be useful for keeping the optimisation of medical exposures faithful to the development of radiological practice.

Interventional cardiac procedures can be complex and involve extensive use of low dose rate fluoroscopy and high dose rate in image acquisition mode; hence, staff may receive significant radiation exposure. Radiation exposure to operators was assessed in 173 procedures. Fluoroscopy time, number of acquired images and dose-area product were recorded and occupational dose assessed with thermoluminescence dosemeters. The effective dose to the operator was compared with relevant literature data: values found were generally lower than those reported for other interventional cardiology laboratories. This is probably because of the strict radiation protection policy in our centre. Higher effective doses were found for defibrillator implantation and percutaneous transluminal coronary angiography procedures; for other cardiac procedures, effective dose was lower. Yearly extrapolated occupational doses to cardiologists are lower than the regulatory dose limit and in the lower band of doses reported in the literature.

The aim of our investigation was to prospectively measure the patient radiation exposure from different cardiological procedures performed in the Catheterisation laboratory of the University Hospital Gasthuisberg in Leuven. The following local reference values were proposed: 40, 47 and 80 Gycm2 for coronary angiography (CA) or angioplasty (PTCA and stent implantation for elective patients), radio frequency ablation with angiographic images and CA plus ad hoc PTCA, respectively.

In interventional cardiology (IC) staff can be exposed to high dose levels due to the long fluoroscopy procedures performed. Staff dosimetry can yield information on the optimisation level of radiation protection, which is influenced by the equipment performance, auxiliary protection devices, training in radiation protection and procedure complexity. Staff exposure data assessed in haemodynamic laboratories of four hospitals in Spain, Greece and Italy participating in the DIMOND concerted action are analysed and compared with data in the literature.

Advances in imaging technology have facilitated the development of increasingly complex interventional cardiac equipment. Consequently, there is a need for definitive equipment requirements. The aim of the study is to assess the performances of different cardiac angiographic systems. A questionnaire was sent to centres participating in SENTINEL Project to collect dosimetry data (typical entrance dose rate in fluoroscopy and imaging mode), image quality evaluations (low and high contrast resolutions) and KAP calibration factors. Results from this survey could contribute to the explanation of patient dose variability in angiographic cardiac procedures and to derive reference levels for cardiac angiographic equipment performance parameters. [ABSTRACT FROM AUTHOR]

Patient doses for a few common fluoroscopy-guided procedures in interventional radiology (IR) (excluding cardiology) were collected from a few radiological departments in 13 European countries. The major aim was to evaluate patient doses for the basis of the reference levels. In total, data for 20 procedures for about 1300 patients were collected. There were many-fold variations in the number of IR equipment and procedures per population, in the entrance dose rates, and in the patient dose data (total dose area product or DAP, fluoroscopy time and number of frames). There was no clear correlation between the total DAP and entrance dose rate, or between the total DAP and fluoroscopy time, indicating that a number of parameters affect the differences. Because of the limited number of patients, preliminary reference levels were proposed only for a few procedures. There is a need to improve the optimisation of IR procedures and their definitions and grouping, in order to account for their different complexities. [ABSTRACT FROM AUTHOR]

This article summarizes the dosimetric results of an International Atomic Energy Agency coordinated research program to investigate the feasibility of adopting guidance levels for invasive coronary artery procedures. The main study collected clinical data from hospitals located in five countries. A total of 2265 coronary angiograms (CA) and 1844 percutaneous coronary interventions (PCI) were analyzed. Substudies evaluated the dosimetric performance of 14 fluoroscopes, skin dose maps obtained using film, the quality of CA procedures, and the complexity of PCI procedures. Kerma-area product (PKA) guidance levels of 50 and 125 Gy cm2 are suggested for CA and PCI procedures. These levels should be adjusted for the complexity of the procedures performed in a given institution. [ABSTRACT FROM AUTHOR]

Interventional radiology contributes a significant proportion of the collective dose of the population from medical exposures. Interventional radiology procedures are usually fluoroscopy-guided diagnostic and therapeutic interventions. When complex procedures are performed or procedures are repeated for the same patient, high-radiation dose levels can occur because procedures often require long fluoroscopy times and require high-quality images. For all of these reasons, dosimetric evaluations in interventional radiology are widely increasing. Patient dosimetry methods currently used in interventional radiology may be divided into three categories according to dosimetry purpose: (I) dosimetry for stochastic risk evaluation, (II) dosimetry for quality assurance and (III) dosimetry to prevent the deterministic effects of radiation. A short description of dosimetric methods used in interventional cardiology practice and relevant published dosimetric data are reported. [ABSTRACT FROM AUTHOR]

The paper explores the level of information contained within the DICOM header in images from various cardiology systems. Data were obtained in the European DIMOND survey on image quality (Italy, Ireland, Belgium, Greece and Spain). Images from five standard diagnostic cardiology procedures carried out in six European hospitals have been analysed. DICOM header information was extracted to a database in order to analyse how it could help in the optimisation of the procedures. The level of data contained in the headers differs widely between cardiology systems. None of the X-ray systems in the 2002 survey archives the dosimetric data in the DICOM header. The mean number of runs per procedure ranges between 7.5 and 15.4 and the mean number of frames per procedure between 575 and 1417. Differences in kVp, mA, pulse time, distances and C-arm angulations are substantial and suggest that there exists a wide range for optimisation. [ABSTRACT FROM AUTHOR]

The multicentre assessment of a procedure complexity index (CI) for the introduction of reference levels (RLs) in percutaneous transluminal coronary angioplasties (PTCA) is presented here. PTCAs were investigated based on methodology proposed by Bernardi et al. Multiple linear stepwise regression analysis, including clinical, anatomical and technical factors, was performed to obtain fluoroscopy time predictors. Based on these regression coefficients, a scoring system was defined and CI obtained. CI was used to classify dose values into three groups: low, medium and high complexity procedures, since there was good correlation (r = 0.41; P < 0.001) between dose-area product (DAP) and CI. CI groups were determined by an ANOVA test, and the resulting DAP and fluoroscopy time third quartiles suggested as preliminary RLs in PTCA, as a function of procedure complexity. PTCA preliminary RLs for DAP are 54, 76 and 127 Gy cm², and 12, 20 and 27 min for fluoroscopy time, for the three CI groups. [ABSTRACT FROM AUTHOR]

Dynamic digital fiat-panel (FD) imaging technology is characterised by a higher sensitivity and image quality compared to image intensifier (II) technology. In this study, an angiography system based on II and one based on FD were compared with respect to system performance and impact of patient dose in interventional cardiology. When entrance surface air kerma rates are measured, the FD system requires a reduced dose rate, of up to 40%. For coronary angiography (CA), fluoroscopy time (FI') and dose-area product (DAP) were 4.3±5.0 rain and 31.2±30.2 Gy cm² on the II system and 4.4±3.8 min and 33.4±19.2 Gy cm² with the FD system. For percutaneous transluminal coronary angiography, FT and DAP were 11.4±10.7 min and 52.1±45.0 Gy cm² on II and 10.7±8.7 min and 66.9±54.4 Gy cm² on DF. Data comparison suggests that reduced entrance dose rates do not automatically imply a reduction of patient dose in clinical practice. [ABSTRACT FROM AUTHOR]

Abstract–: The International Commission on Radiological Protection (ICRP) first introduced the term ‘diagnostic reference level’ (DRL) in 1996 in Publication 73. The concept was subsequently developed further, and practical guidance was provided in 2001. The DRL has been proven to be an effective tool that aids in optimisation of protection in the medical exposure of patients for diagnostic and interventional procedures. However, with time, it has become evident that additional advice is needed. There are issues related to definitions of the terms used in previous guidance, determination of the values for DRLs, the appropriate interval for re-evaluating and updating these values, appropriate use of DRLs in clinical practice, methods for practical application of DRLs, and application of the DRL concept to newer imaging technologies. This publication is intended as a further source of information and guidance on these issues. Some terminology has been clarified. In addition, this publication recommends quantities for use as DRLs for various imaging modalities, and provides information on the use of DRLs for interventional procedures and in paediatric imaging. It suggests modifications in the conduct of DRL surveys that take advantage of automated reporting of radiation-dose-related quantities, and highlights the importance of including information on DRLs in training programmes for healthcare workers. The target audience for this publication is national, regional, and local authorities; professional societies; and facilities that use ionising radiation for medical purposes, and responsible staff within these facilities. A full set of the Commission’s recommendations is provided. [ABSTRACT FROM AUTHOR]

One the most complicated gastrointestinal procedures, endoscopic retrograde cholangio-pancreatography (ERCP) uses fluoroscopy guidance of an endoscope to diagnose and treat hepatobiliary system pathologies. As is true of all approved interventional radiology, it is justified by the massive benefit that it is capable of delivering, one which for the patient far outweighs the risks from radiation exposure. Nevertheless, for both patients and staff there is a need to minimize the risk of carcinogenesis and the potential for tissue reactions. Recent concern has been shown in regard to radiation induced eye lens opacifications and cataract, most particularly for the members of staff who during their regular theatre practice are in closest contact with the patient. Therefore, optimum balance between benefit versus radiation risk is required. This study reviews patient and staff dose during ERCP procedures, also seeking to provide comprehensive data regarding radiation exposure management techniques. Patient and staff doses depend on the operators, equipment and patient related factors, benefitting from awareness and experience in respect of radiation protection techniques and the availability of modern fluoroscopic equipment. It is apparent that in high workload departments, staff doses to eye lens may exceed the limits on annual exposure. • Previous studies in patients and occupational dosimetry had been studies. • Patients and staff remain constant regardless of the X ray technology development. • ERCP is safe during pregnancy for patients and pregnant workers. • It is apparent that in high workload departments, staff doses to eye lens may exceed the limits on annual exposure. • Lack of training and monitoring services in gastroenterology department are frequently reported. [ABSTRACT FROM AUTHOR]