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During transcatheter aortic valve implantations (TAVI) and other percutaneous structural procedures, some patients may need close anesthesiological care, thus exposing the anaesthesiologist to x-rays. This work aims to investigate the radiation dose received by anaesthesiologists during these specific procedures in order to improve their radiological protection. Occupational radiation doses were measured prospectively during percutaneous structural procedures in several health professionals using electronic dosimeters worn over the apron at chest level. A sample of 49 procedures were recorded, where the anaesthesiologists' average dose per procedure resulted 13 times higher than that of interventional cardiologists. The average dose per procedure received over the protection apron during TAVIs by the anaesthesiologist was 0.13 mSv, with a maximum value of 0.69 mSv. Taking these figures as a conservative estimation of the eye lens dose, an anaesthesiologist could participate in around 150 procedures before reaching the regulatory annual dose limit for the lens of the eye in Europe (20 mSv). In those clinical procedures where patients need close anesthesiological care, the anaesthesiologists might receive high radiation doses increasing the risk for cataracts and the risk of stochastic radiation effects. The proper use of occupational dosimeters will help identify these situations. It is recommended to use a mobile shielding barrier to reduce radiation exposure to acceptable levels in these situations.

Occupational protection is still a challenge for interventional cardiology. One of the main problems is the occasional improper use of the ceiling suspended screen. We present a methodology to audit the correct use of the shielding using active electronic dosimeters. To improve the protection, we suggest the use of an alert based on the ratio between the occupational dose per procedure, measured by a personal electronic dosimeter over the lead apron, and the dose measured by an unshielded dosimeter, located at the C-arm. The new electronic dosimeters and the automatic dose management systems allow processing the dosimetric data for individual procedures and for the radiation events, sending the values (wireless) to a central database. We selected six interventional cardiologists and analysed 385 interventional procedures involving about 30 000 radiation events. Our results suggest that for individual procedures, standard values of the ratio between operator dose and the C-arm reference dose, should be between 1%-2% for a proper use of the shielding. Percentage values ≥5%-10% for individual procedures, require an analysis of the different radiation events to identify the lack of occupational protection and suggest corrective actions. In our sample, half of the operators should improve the use of the shielding in around 20% of the procedures. Using this ratio as an alert to operators allows optimising occupational radiation protection and discriminating between high occupational doses derived from complex procedures and high doses due to the improper use of the protective screen., (© 2020 Society for Radiological Protection. Published on behalf of SRP by IOP Publishing Limited. All rights reserved.)

Over recent years, an increasing number of fluoroscopically guided interventions (FGIs) have been performed by radiologists and non-radiologists. Also, the number of complex interventional procedures has increased. In the late nineties, first reports of skin injuries appeared in the literature. The medical community responded through increased awareness for radiation protection and public authorities by recommendations and legislation, for example, the European Basic Safety Standards (EU-BSS) which were published in 2014, or the international Basic Safety Standards (BSS). Implementation of the EU-BSS requires concerted action from interventionalists, radiographers, medical physics experts and competent national authorities. Interventionalists should play an important role in this project since implementation of the EU-BSS will affect their daily practice. This paper discusses some important issues of the EU-BSS such as unintended and accidental radiation exposures of patients, the meaning of significant dose events and how to deal with patients who were exposed to a substantial radiation dose with the risk of tissue injuries. In addition, this paper provides practical advice on how to implement alert and trigger levels in daily practice of FGIs in order to increase patient safety.

The European Directive 2013/59/EURATOM requires member states of the European Union to ensure justification and optimisation of the radiological procedures and to include information on patient exposure as part of the report of the examinations. The EuroSafe Imaging campaign of the European Society of Radiology created a working group (WG) on "Dosimetry for imaging in clinical practice" with the aim to help with the dosimetry aspects required by European and national regulations. The primary focus topics were selected and a survey among the experts of the WG, allowed suggesting some initial consensus approaches.For information on patient exposure, it was agreed to include the dosimetric values reported by the imaging modalities (validated by a medical physics expert). It was also suggested to prepare educational material on dosimetric quantities for patients. Individual optimisation was considered a challenge, especially for interventional procedures. In these cases, patient and occupational doses should be part of the global optimisation process and trigger levels should be defined to avoid skin radiation injuries. Diagnostic Reference Levels (DRLs) always need to be considered for comparison with periodic patient dose audits. In the case of accidental or unintended exposures, a report should be produced for the Quality Assurance programme, together with an educational note to avoid the repetition of incidents. Dose registry and management systems should allow fulfilling the regulatory requirements of national and European regulations. In a second step, and after the initial experience with the Directive implementation, a wider survey will be considered.

There is a large variation in the factors used to estimate effective doses from kerma area product (KAP) for interventional cardiology. These factors are required to estimate population doses. This paper presents the results for this conversion factor for cardiac procedures using tissue weighting factors of ICRP-103 and the impact of the added copper filtration in the X-ray beam. The data from 925 cardiac procedures and 75,347 radiation events were collected from two angiography laboratories using the DICOM Radiation Dose Structured Reports (RDSR). Effective doses were calculated with Monte Carlo software and the dosimetric, technical and geometrical information included in the RDSR. In one laboratory, with an X-ray system without Cu filtration for the cine runs, a factor of 0.21 ± 0.05 mSv/(Gy·cm 2 ) was obtained. In other laboratory, incorporating a patient dose reduction technique, and 0.4 mm of Cu filtration for cine runs, the conversion factor was 0.29 ± 0.05 mSv/(Gy·cm 2 ). The analysis of the radiation events for the different Cu filtrations (0.0; 0.1; 0.4 and 0.9 mm) resulted in conversion factors of: 0.16; 0.27; 0.34 and 0.40 mSv/(Gy·cm 2 ) respectively. The estimation of effective and population doses from KAP should take into account the Cu filtration in the X-ray beam. For the X-ray system with patient dose reduction technique, using 0.4 mm Cu for cine runs, the global conversion factor increased by 38%, from 0.21 to 0.29 mSv/(Gy·cm 2 ) in comparison to the standard X-ray system with a protocol that did not include copper filtration for cine acquisitions., (Copyright © 2019 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)

The aims of the present study were to present the frequency of multiple interventional cardiac procedures for a certain group of patients obtained at one of the largest paediatric hospitals in Chile. In addition it has been analysed cumulative kerma area product (KAP) and cumulative air kerma (CAK), and calculated organ doses for the patient groups undergoing 2, 3 and ≥ 4 procedures, using Monte Carlo software. Effective doses were also estimated for epidemiological purposes and to permit comparison with other imaging procedures. The sample used corresponds to the last 9 years and refers to a total of 1521 paediatric patients and 1824 interventional cardiac procedures. The results for frequency were: 13.7% of patients underwent 2 procedures, 4.1% underwent 3 procedures and 1.4% underwent 4 or more procedures. The median KAP and CAK values measured for the cumulative procedures in these three groups of patients were 3.7, 5.4 and 10.8 Gy·cm 2 and 59.9, 83.2 and 147.6 mGy, respectively. In terms of the most irradiated organs during interventional cardiac procedures, the highest median values (for the group of ≥4 procedures) were: active bone marrow 5.0 mGy, lungs 23.5 mGy, oesophagus 15.2 mGy, thyroid 7.8 mGy and breast 11.0 mGy. Median dose value to the heart (for the group of ≥4 procedures) was 12.7 mGy. Median values in terms of calculated effective dose for the three patient groups (with 2, 3 and ≥4 procedures) were 3.4, 5.9 and 8.7 mSv, respectively., (Copyright © 2019 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)

Interventional cardiac procedures may be associated with high patient doses and therefore require special attention to protect the patients from radiation injuries such as skin erythema, cardiovascular tissue reactions or radiation-induced cancer. In this study, patient exposure data is collected from 13 countries (37 clinics and nearly 50 interventional rooms) and for 10 different procedures. Dose data was collected from a total of 14,922 interventional cardiology procedures. Based on these data European diagnostic reference levels (DRL) for air kerma-area product are suggested for coronary angiography (CA, DRL = 35 Gy cm 2 ), percutaneous coronary intervention (PCI, 85 Gy cm 2 ), transcatheter aortic valve implantation (TAVI, 130 Gy cm 2 ), electrophysiological procedures (12 Gy cm 2 ) and pacemaker implantations. Pacemaker implantations were further divided into single-chamber (2.5 Gy cm 2 ) and dual chamber (3.5 Gy cm 2 ) procedures and implantations of cardiac resynchronization therapy pacemaker (18 Gy cm 2 ). Results show that relatively new techniques such as TAVI and treatment of chronic total occlusion (CTO) often produce relatively high doses, and thus emphasises the need for use of an optimization tool such as DRL to assist in reducing patient exposure. The generic DRL presented here facilitate comparison of patient exposure in interventional cardiology., (Copyright © 2018 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)

As in any medical intervention, there is either a known or an anticipated benefit to the patient from undergoing a medical imaging procedure. This benefit is generally significant, as demonstrated by the manner in which medical imaging has transformed clinical medicine. At the same time, when it comes to imaging that deploys ionising radiation, there is a potential associated risk from radiation. Radiation risk has been recognised as a key liability in the practice of medical imaging, creating a motivation for radiation dose optimisation. The level of radiation dose and risk in imaging varies but is generally low. Thus, from the epidemiological perspective, this makes the estimation of the precise level of associated risk highly uncertain. However, in spite of the low magnitude and high uncertainty of this risk, its possibility cannot easily be refuted. Therefore, given the moral obligation of healthcare providers, 'first, do no harm,' there is an ethical obligation to mitigate this risk. Precisely how to achieve this goal scientifically and practically within a coherent system has been an open question. To address this need, in 2016, the International Atomic Energy Agency (IAEA) organised a summit to clarify the role of Diagnostic Reference Levels to optimise imaging dose, summarised into an initial report (Järvinen et al 2017 Journal of Medical Imaging 4 031214). Through a consensus building exercise, the summit further concluded that the imaging optimisation goal goes beyond dose alone, and should include image quality as a means to include both the benefit and the safety of the exam. The present, second report details the deliberation of the summit on imaging optimisation.

The International Commission on Radiological Protection recommends that occupational protection and patient protection be managed in an integrated approach. This paper describes the experience and the initial results of a system able to register and to process simultaneously staff and patient doses in interventional cardiology and the practical use of this system in the optimisation of occupational exposure. The system used simultaneously collects and manages patient and staff doses for all radiation events. The personal electronic dosimeters worn over the protective apron of health professionals working inside catheterisation laboratories can send (wireless) doses and dose rate values to an X-hub and provide the operators inside the catheterisation rooms with real-time information. Individual and global reports for all the health professionals may be periodically obtained from the system to help with the optimisation. The results for eight cardiologists, one fellow and four nurses for a total of 2468 interventional cardiology procedures and 3207 occupational dose values collected over one year are presented here. Annual doses Hp(10) measured over the apron for cardiologists ranged from 0.3 to 6.3 mSv. For the cardiologist, the ratio between occupational doses (over the apron) and patient doses ranged from 0.05 to 0.23 μSv Gy -1 cm -2 , with a mean value of 0.12 μSv Gy -1 cm -2 . The system allows defining optimisation strategies by comparing the results between the different operators while considering the workload and complexity of the procedures (based on the total Kerma Area Product managed by the different operators). The registration of the date and time of the occupational radiation doses allows auditing the use of the personal dosimeters worn by the various operators.

Introduction: The International Atomic Energy Agency (IAEA) organized the 3rd international conference on radiation protection (RP) of patients in December 2017. This paper presents the conclusions on the interventional procedures (IP) session., Material and Methods: The IAEA conference was conducted as a series of plenary sessions followed by various thematic sessions. "Radiation protection of patients and staff in interventional procedures" session keynote speakers presented information on: 1) Risk management of skin injuries, 2) Occupational radiation risks and 3) RP for paediatric patients. Then, a summary of the session-related papers was presented by a rapporteur, followed by an open question-and-answer discussion., Results: Sixty-seven percent (67%) of papers came from Europe. Forty-four percent (44%) were patient studies, 44% were occupational and 12% were combined studies. Occupational studies were mostly on eye lens dosimetry. The rest were on scattered radiation measurements and dose tracking. The majority of patient studies related to patient exposure with only one study on paediatric patients. Automatic patient dose reporting is considered as a first step for dose optimization. Despite efforts, paediatric IP radiation dose data are still scarce. The keynote speakers outlined recent achievements but also challenges in the field. Forecasting technology, task-specific targeted education from educators familiar with the clinical situation, more accurate estimation of lens doses and improved identification of high-risk professional groups are some of the areas they focused on., Conclusions: Manufacturers play an important role in making patients safer. Low dose technologies are still expensive and manufacturers should make these affordable in less resourced countries. Automatic patient dose reporting and real-time skin dose map are important for dose optimization. Clinical audit and better QA processes together with more studies on the impact of lens opacities in clinical practice and on paediatric patients are needed., (Copyright © 2018 Associazione Italiana di Fisica Medica. All rights reserved.)

The goal of the present study was to propose a set of national diagnostic reference levels (DRLs) in Costa Rica for paediatric interventional cardiology (IC) procedures classified by age and weight and to estimate the collective dose of the paediatric population from these intervention practices. The data collection period was May 2016 to May 2017. The third quartile of patient dose data distributions for kerma-area product (KAP) values was set as the national DRLs. A sample of 154 paediatric IC procedures (collected in the national paediatric hospital with a single x-ray system) was used and divided into four age ranges and five weight ranges. The national DRLs obtained for KAPs by age range were 1.79 Gy cm 2 (<1 year) to 23.0 Gy cm 2 (10-15 years). The national DRLs obtained for KAPs by weight range were 1.0 Gy cm 2 (<10 kg) to 49.6 Gy cm 2 (50-79 kg). The contribution to the collective dose of the population of Costa Rica amounted to 0.78 person Sv.

Medical staff should not be exposed to the primary X-ray beam during fluoroscopy-guided interventional procedures (FGIP). The main source of staff exposure is scatter radiation from the patient, which can be significant. Although many aspects of X-ray exposure to the patient as well as occupational exposure to interventional radiologists and other staff are strongly regulated and monitored in most countries, it is surprising how loosely the labeling and testing of the protective aprons is regulated. Interventional radiologists (IRs) have to be experts in interventional radiology as well as in basic facts regarding ways to provide a satisfactory level of protection from occupational exposure. IRs, however, are not familiar with the apron testing methods. The accompanying documents provided with aprons by manufacturers may not be informative enough. Vendors often report apron effectiveness at a single beam quality and attenuation. The vendor reports repeatedly disagree with independent reports, which clearly show that the attenuation of these garments at other important unreported energies may be lower than expected. Better trust no one and check your protective garment yourself, or, better yet, consult a medical physicist when making purchasing decisions related to protective garments. Each interventionist should choose garments that are appropriately protective for that individual's practice. Review of past personal dosimetry results and consultation with a medical physicist can help the IR make the best decision. This article will help the reader to understand why all protective garments are not created equally, and provides some practical tools that will allow safe and healthy practice in FGIP., (Copyright © 2018 Elsevier Inc. All rights reserved.)

During the International Conference on Radiation Protection in Medicine held in Bonn in 2012, several areas for improvement were identified, including specific actions related with justification, optimization, role of manufacturers, radiation protection education and training, strategic research, data collection on medical and occupational exposures, prevention of incidents and accidents, radiation safety culture, risk-benefit dialogue and implementation of the radiation safety standards. The outcomes of the Bonn Conference were summarized in the so-called 'Bonn Call for Action', identifying 10 priority actions to enhance RP in medicine. Trying to analyse the progress in the implementation of this 'Call for Action' in the Ibero-American region, several international organizations organized the 'Ibero-American Conference on Radiation Protection in Medicine' (Conferencia Iberoamericana sobre Protección Radiológica en Medicina, CIPRaM) held in Madrid, in October 2016. CIPRaM was structured in eight thematic sessions dealing with: diagnostic and dental radiology, image guided interventional radiology, nuclear medicine, radiation therapy, health authorities and radiation protection regulators, professional associations of technologists and nurses, professional associations of medical physicists and radiation protection experts, and universities and researchers in radiation protection in medicine. This paper summarizes the main results of that Conference based on the consensus achieved about main problems, solutions, and indicators to evaluate the implementation of the proposed solutions.

Purpose: This review summarizes the conclusions and recommendations of the new National Council on Radiation Protection and Measurements (NCRP) Commentary No. 26 guidance on radiation dose limits for the lens of the eye. The NCRP addressed radiation protection principles in respect to the lens of the eye, discussed the current understanding of eye biology and lens effects, reviewed and evaluated epidemiology, and assessed exposed populations with the potential for significant radiation exposures to the lens while suggesting monitoring and protection practices., Conclusions: Radiation-induced damage to the lens of the eye can include the loss of clarity resulting in opacification or clouding several years after exposure. The impact is highly dependent on the type of radiation, how the exposure of the lens was delivered, the genetic susceptibilities of the individual exposed, and the location of the opacity relative to the visual axis of the individual. The preponderance of epidemiological evidence suggests that lens damage could occur at lower doses than previously considered and the NCRP has determined that it is prudent to reduce the recommended annual lens of the eye occupational dose limit from an equivalent dose of 150 mSv to an absorbed dose of 50 mGy. Significant additional research is still needed in the following areas: comprehensive evaluation of the overall effects of ionizing radiation on the eye, dosimetry methodology and dose-sparing optimization techniques, additional high quality epidemiology studies, and a basic understanding of the mechanisms of cataract development.

The purpose of this work is to evaluate the impact of the imaging protocol as part of the optimisation of patient doses in interventional cardiology. This paper reports the results of an initial study to refine the existing fluoroscopy and cine settings, evaluates a new imaging protocol by measuring the image quality and phantom entrance air kerma values, and tests the clinical implementation of the new protocol in terms of the reduction in patient doses and the impact on clinical images. The initial study developed a new fluoroscopy mode using 7.5 frames s -1 (instead of the previous 15 frames s -1 ) with a similar dose/frame and a reduction of approximately 26% in dose/frame for the existing standard cine mode. For the new imaging protocol, the reduction in entrance air kerma was characterised for water depths of 16, 20, and 24 cm and the image quality was evaluated using a Leeds test object. A reduction in dose of around 50% was observed for the low fluoroscopy mode and an 18%-38% reduction was measured for cine. The image quality was unchanged in fluoroscopy mode and did not suffer noticeable alterations in cine mode. In the clinical implementation, cardiologists evaluated the new imaging protocol in clinical practice and cooperated with medical physicists to ensure full optimisation. The image quality criteria evaluated the ability to visualise the standard coronary arteries and small vessels (<2 mm), and the proper visualisation of the heart and diaphragm. A total of 1635 interventional cardiac procedures were assessed. The median kerma-area product exhibited a reduction of 37% for CA and 43% for PTCA examinations, and the quality of the clinical images was considered sufficient for standard clinical practice.

The aim of this study was to present the results of organ and effective doses for paediatric patients for different types of interventional cardiology procedures for age and weight groups, derived from a patient dosimetry pilot programme carried out in Chile, under the auspices of the International Atomic Energy Agency. Over seven years, a retrospective collection of demographic and patient dose data was obtained: age, gender, weight, height, number of cine series, total number of cine frames, fluoroscopy time, dose-area product (DAP) and cumulative dose at patient entrance reference point. Monte Carlo software was used to calculate organ and effective doses. 1506 procedures were divided into four age and seven weight groups. Organ doses (median values) for diagnostic and therapeutic procedures were: active bone marrow 0.90 and 0.64mGy; heart 1.99 and 1.46mGy; lungs 3.56 and 2.59mGy; thyroid 1.27 and 0.83; and breast (in the case of females) 1.78 and 1.36mGy. The ranges for effective doses (median values) and weight bands were 1.2-3.9mSv for diagnostic procedures and 1.0-2.5mSv for therapeutic procedures. The resulting conversion factors (median values) to estimate effective dose from DAP (in mSv/Gy.cm2) were: 1.70; 0.89; 0.58; and 0.40, for age groups of <1year, 1-<5years, 5-<10years and 10-<16years, respectively. The obtained set of dose values will enable comparisons with other imaging procedures (comparing the same age bands) for justification and optimization purposes., (Copyright © 2017. Published by Elsevier Ltd.)

Optimization is one of the key concepts of radiation protection in medical imaging. In practice, it involves compromising between the image quality and dose to the patient; the dose should not be higher than necessary to achieve an image quality (or diagnostic information) needed for the clinical task. Monitoring patient dose is a key requirement toward optimization. The concept of diagnostic reference level (DRL) was introduced by the International Commission on Radiological Protection as a practical tool for optimization. Unfortunately, this concept has not been applied consistently worldwide. To review the current strengths and weaknesses worldwide and to promote improvements, the International Atomic Energy Agency organized a Technical Meeting on patient dose monitoring and the use of DRLs on May 2016. This paper reports a summary of the findings and conclusions from the meeting. The strengths and weaknesses were generally different in less-developed countries compared with developed countries. Possible improvements were suggested in six areas: human resources and responsibilities, training, safety and quality culture, regulations, funding, and tools and methods. An overall conclusion was that radiation protection requires a patient-centric approach and a transfer from purely reactive to increasingly proactive optimization, whereby the best outcome is expected from good teamwork.

The aim of this study was to evaluate the occupational radiation dose in interventional cardiology by using a shielding drape on the patient. A random study with and without the protective material was conducted. The following control parameters were registered: demographic data, number of stents, contrast media volume, fluoroscopy time, number of cine images, kerma-area product and cumulative air kerma. Occupational dose data were obtained by electronic active dosemeters. No statistically significant differences in the analysed control parameters were registered. The median dose value received by the interventional cardiologist was 50% lower in the group with a shielding drape with a statistically significant p-value <0.001. In addition, the median value of the maximum scatter radiation dose was 31% lower in this group with a statistically significant p-value <0.001. This study showed that a shielding drape is a useful tool for reducing the occupational radiation dose in a cardiac catheterisation laboratory., (© The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

This paper sets out guidelines for managing radiation exposure incidents involving patients in diagnostic and interventional radiology. The work is based on collation of experiences from representatives of international and national organizations for radiologists, medical physicists, radiographers, regulators, and equipment manufacturers, derived from an International Atomic Energy Agency Technical Meeting. More serious overexposures can result in skin doses high enough to produce tissue reactions, in interventional procedures and computed tomography, most notably from perfusion studies. A major factor involved has been deficiencies in training of staff in operation of equipment and optimization techniques. The use of checklists and time outs before procedures commence, and dose alerts when critical levels are reached during procedures, can provide safeguards to reduce the risks of these effects occurring. However, unintended and accidental overexposures resulting in relatively small additional doses can take place in any diagnostic or interventional x-ray procedure and it is important to learn from errors that occur, as these may lead to increased risks of stochastic effects. Such events may involve the wrong examinations, procedural errors, or equipment faults. Guidance is given on prevention, investigation, and dose calculation for radiology exposure incidents within healthcare facilities. Responsibilities should be clearly set out in formal policies, and procedures should be in place to ensure that root causes are identified and deficiencies addressed. When an overexposure of a patient or an unintended exposure of a foetus occurs, the foetal, organ, skin, and/or effective dose may be estimated from exposure data. When doses are very low, generic values for the examination may be sufficient, but a full assessment of doses to all exposed organs and tissues may sometimes be required. The use of general terminology to describe risks from stochastic effects is recommended rather than the calculation of numerical values, as these are misleading when applied to individuals.

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.

The purpose of this work is to evaluate radiation doses to the lens of urologists during interventional procedures and to compare them with values measured during interventional radiology, cardiology and vascular surgery. The measurements were carried out in a surgical theatre using a mobile C-arm system and electronic occupational dosimeters (worn over the lead apron). Patient and staff dose measurements were collected in a sample of 34 urology interventions (nephrolithotomies). The same dosimetry system was used in other medical specialties for comparison purposes. Median and 3rd quartile values for urology procedures were: patient doses 30 and 40 Gy cm(2); personal dose equivalent Hp(10) over the apron (μSv/procedure): 393 and 848 (for urologists); 21 and 39 (for nurses). Median values of over apron dose per procedure for urologists resulted 18.7 times higher than those measured for radiologists and cardiologists working with proper protection (using ceiling suspended screens) in catheterisation laboratories, and 4.2 times higher than the values measured for vascular surgeons at the same hospital. Comparison with passive dosimeters worn near the eyes suggests that dosimeters worn over the apron could be a reasonable conservative estimate for ocular doses for interventional urology. Authors recommend that at least the main surgeon uses protective eyewear during interventional urology procedures.

New European regulation regarding radiological protection of workers and more specifically the new occupational dose limit for the eye lens recently reduced to 20 mSv yr(-1) may affect interventional cardiologists. This paper presents a set of measurements of occupational doses performed in five interventional cardiology centres and then compared with the new dose limit. The measurement of occupational doses was performed over the apron at chest level using electronic dosemeters recording H p(10). In one of the centres, scatter dose at goggles was also measured with optically stimulated luminescence dosemeters calibrated in terms of H p(0.07). An average H p(10) over the apron of 46 μSv/procedure was measured for cardiologists. Lower doses were noted in other professionals like second cardiologists, nurses or anaesthetists. Procedures for valvular and other structural heart diseases involved the highest occupational doses, averaging over 100 μSv/procedure. Important differences in occupational doses among centres may be indicative of different radiation protection habits. The new occupational dose limit for the eye lens is likely to be exceeded by those among the interventionalists who do not use protection tools (ceiling suspended screen and/or goggles) even with standard workloads.

Previous National Council on Radiation Protection and Measurements (NCRP) publications have addressed the issues of risk and dose limitation in radiation protection and included guidance on specific organs and the lens of the eye. NCRP decided to prepare an updated commentary intended to enhance the previous recommendations provided in earlier reports. The NCRP Scientific Committee 1-23 (SC 1-23) is charged with preparing a commentary that will evaluate recent studies on the radiation dose response for the development of cataracts and also consider the type and severity of the cataracts as well as the dose rate; provide guidance on whether existing dose limits to the lens of the eye should be changed in the United States; and suggest research needs regarding radiation effects on and dose limits to the lens of the eye. A status of the ongoing work of SC 1-23 was presented at the Annual Meeting, "Changing Regulations and Radiation Guidance: What Does the Future Hold?" The following represents a synopsis of a few main points in the current draft commentary. It is likely that several changes will be forthcoming as SC 1-23 responds to subject matter expert review and develops a final document, expected by mid 2016.

The aim of this paper was to determine experimentally the entrance surface air kerma (ESAK) and kerma-area product (KAP) levels to patients and scatter doses at the cardiologist's eyes during paediatric interventional cardiology (IC) procedures for Chile, on the basis of measurements taken from X-ray systems characterization for different thicknesses of polymethyl methacrylate, together with the average values of fluoroscopy time and number of cine frames for ten paediatric IC procedures. The range of cumulative ESAK values when the different clinical procedures were simulated was from 2 to 1100 mGy. KAP values ranged from 0.30 to 150 Gy cm(2). Scatter doses at cardiologist's eyes for the simulated procedures ranged from 0.20 to 116 µSv per procedure. Large differences between the X-ray systems were found in our study. Standardized guidelines in terms of X-ray system setting and protocols should be developed for hospitals that perform paediatric IC procedures in Chile., (Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)

The aims of this work were to report the results of a national survey on entrance surface air kerma (ESAK) values for different phantom thicknesses and operation modes in paediatric interventional cardiology (IC) systems and to compare them with previous values. The national survey also offers suggested investigation levels (ILs) for ESAK in paediatric cardiac procedures. ESAK was measured on phantoms of 4-16 cm thickness of polymethyl methacrylate slabs. For low fluoroscopy mode (FM), ESAK rates ranged from 0.11 to 33.1 mGy min(-1) and for high FM from 0.34 to 61.0 mGy min(-1). For cine mode, values of ESAK per frame were from 1.9 to 78.2 µGy fr(-1). The ILs were suggested as the third quartile of the values measured. This research showed lower ESAK values than in previous research, particularly for ESAK values in cine modes. This work represents a first step towards launching a national programme in paediatric dosimetry for IC procedures., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Reducing occupational radiation dose in cardiac catheterisation laboratories is one of the objectives of the radiation protection system because the procedures performed involve high levels of radiation compared with others in health care. Recommendations on protection methods used are referred to different structural types and personal protection tools. In this work, the effectiveness of a shielding drape above the patient in different geometric shapes for a standard procedure in interventional cardiology was evaluated. Values of personal dose equivalent Hp(10) obtained simultaneously with three active electronic semiconductor dosemeters located at the usual position of staff and at the C-arm have been used to show the usefulness of the shielding drape., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

An experience with an automated infuser device at a university hospital is presented in this paper. Occupational doses at operators' fingertips were measured using optically stimulated luminescence dosemeters for two different scenarios: (i) using a semi-automatic system to prepare the fluorodesoxiglucose (FDG) injections that were delivered to the patient manually and (ii) using an automated infusion device that prepares and delivers the FDG dose. The accuracy of the activity prepared by the automatic system was also verified. Reductions in fingertip doses of 60 % using the fully automatic system have been measured. The difference between the programmed and the delivered activity was 2 %. The use of the automatic infuser in the authors' institution has led to a substantial reduction in hand radiation doses. But contamination risks, even though reduced, still exist; therefore, radioisotope manipulation should follow strict radiation protection rules to avoid incidents. Improved accuracy in dose delivery reduces chances of dose misadministration., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

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., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The purpose of this work was to validate a prototype designed to display skin dose maps in real time for clinicians that perform interventional cardiology procedures. Measurements using copper absorbers and three kinds of dosemeters (solid-state, radiochromic film and optically stimulated luminescence) were performed in a catheterisation laboratory. Some clinical results are also discussed. The system provides patient skin doses with acceptable accuracy, taking into account couch shifts, wedge compensation filters and collimation. The greatest source of uncertainty is that resulting from patient shape modelling. From a set of 374 patients recorded, it can be concluded that the peak skin dose (PSD) for patients with the same cumulative air kerma at the patient entrance reference point can be rather different. This real-time skin dose calculator has resulted easier to manage for measuring patient PSDs than other methods based on films or CR plates. As well as an improvement for patient safety, it could prove a useful training tool for clinicians., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The aim of this work was to analyse the radiation dose for patients and staff between X-ray systems, a new biplane with flat-panel detectors (FDs) and a conventional system equipped with image intensifier (II). Entrance surface air kerma (ESAK) and scatter doses were measured on polymethyl methacrylate (PMMA) phantoms of different thicknesses (from 4 to 16 cm). The ESAK values for the different acquisition modes and PMMA thicknesses were higher for the II in comparison with FDs. For the II, the scatter dose rates ranged from 0.67 to 12.2 mSv h(-1) at the eye position of the cardiologist during fluoroscopy and cine modes. At the lower extremities, these values were 1.11 and 24.24 mSv h(-1). In the case of the FDs, these values ranged from 0.24 to 0.67 mSv h(-1) for eye lens and from 0.73 to 2.01 mSv h(-1) for the position of cardiologist's ankle. The newly installed X-ray system showed an average reduction factor of up to 9.7 times for ESAK values. For the staff with an average reduction factor of 15.9 times at the eye position during fluoroscopy and cine modes, no protective tools are used. At the lower extremities, this value was 7.6 times., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Data from one digital mammograph (flat detector active area of 19.2 × 23 cm(2)) were collected over a 1-year period using locally developed software in order to evaluate retakes, their rates, their causes and the possible measures to reduce their occurrence. Among them, 7.1 % of the images were marked as repetitions, and in 16 % of the studies, at least one image was repeated. When evaluating causes of retakes, the primary cause was incorrect positioning (49 %), closely followed by additional retakes in cases of large breasts (44 %). When dealing with large breasts and using a small flat panel, additional images were necessary to fully visualise the breast, and as a consequence, some breast regions received repeated radiation exposure. Moreover, a small detector increases retakes in breasts slightly wrongly positioned. To try and reduce the retake rate, it is important to plan training sessions based on images selected from the retake analysis., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

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., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The purpose of this article is to estimate lens doses using over apron active personal dosemeters in interventional catheterisation laboratories (cardiology IC, neuroradiology IN and radiology IR) and to investigate correlations between occupational lens doses and patient doses. Active electronic personal dosemeters placed over the lead apron were used on a sample of 204 IC procedures, 274 IN and 220 IR (all performed at the same university hospital). Patient dose values (kerma area product) were also recorded to evaluate correlations with occupational doses. Operators used the ceiling-suspended screen in most cases. The median and third quartile values of equivalent dose Hp(10) per procedure measured over the apron for IC, IN and IR resulted, respectively, in 21/67, 19/44 and 24/54 µSv. Patient dose values (median/third quartile) were 75/128, 83/176 and 61/159 Gy cm(2), respectively. The median ratios for dosemeters worn over the apron by operators (protected by the ceiling-suspended screen) and patient doses were 0.36; 0.21 and 0.46 µSv Gy(-1) cm(-2), respectively. With the conservative approach used (lens doses estimated from the over apron chest dosemeter) we came to the conclusion that more than 800 procedures y(-1) and per operator were necessary to reach the new lens dose limit for the three interventional specialties., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The purpose of this paper is to report a set of experimental values of patient and staff doses in a cardiac catheterisation laboratory using the range of radiographic and geometric parameters from routine clinical practice. The data obtained will be available for validation of Monte Carlo calculations and for training purposes. They will also help optimise radiation protection for patients and staff. Experimental measurements were made with an anthropomorphic phantom, and a monoplane flat detector-based X-ray system was used for interventional cardiology procedures. Standard operational protocols used in clinical practice were applied. Around 1000 patient dose and 5000 staff dose values were measured for different operational conditions (angulations, distances, collimation and wedge filter, magnification, phantom thicknesses, using Copper absorber, etc.). Uncertainties were also estimated. Increase factors of 3-10 for patients and staff doses were measured for the different C-arm angulations., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The equivalent dose limit for the eye lens for occupational exposure recommended by the ICRP has been reduced to 20 mSv y(-1) averaged over defined periods of 5 y, with no single year exceeding 50 mSv. The compliance with this new requirement could not be easy in some workplace such as interventional radiology and cardiology. The aim of this study is to evaluate different possible approaches in order to have a good estimate of the eye lens dose during interventional procedures. Measurements were performed with an X-ray system Philips Allura FD-10, using a PMMA phantom to simulate the patient scattered radiation and a Rando phantom to simulate the cardiologist. Thermoluminescence (TL) whole-body and TL eye lens dosemeters together with Philips DoseAware active dosemeters were located on different positions of the Rando phantom to estimate the eye lens dose in typical cardiology procedures. The results show that, for the studied conditions, any of the analysed dosemeter positions are suitable for eye lens dose assessment. However, the centre of the thyroid collar and the left ear position provide a better estimate. Furthermore, in practice, improper use of the ceiling-suspended screen can produce partial protection of some parts of the body, and thus large differences between the measured doses and the actual exposure of the eye could arise if the dosemeter is not situated close to the eye., (© The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Purpose: To present the results of a patient dose evaluation program in pediatric cardiology and propose local diagnostic reference levels (DRLs) for different types of procedure and age range, in addition to suggesting approaches to correlate patient dose values with patient weight. This study was the first conducted in Latin America for pediatric interventional cardiology under the auspices of the International Atomic Energy Agency., Methods: Over three years, the following data regarding demographic and patient dose values were collected: age, gender, weight, height, number of cine series, total number of cine frames, fluoroscopy time (FT), and two dosimetric quantities, dose-area product (DAP) and cumulative dose (CD), at the patient entrance reference point. The third quartile values for FT, DAP, CD, number of cine series, and the DAP/body weight ratio were proposed as the set of quantities to use as local DRLs., Results: Five hundred and seventeen patients were divided into four age groups. Sample sizes by age group were 120 for <1 yr; 213 for 1 to <5 yr; 82 for 5 to <10 yr; and 102 for 10 to <16 yr. The third quartile values obtained for DAP by diagnostic and therapeutic procedures and age range were 1.17 and 1.11 Gy cm2 for <1 yr; 1.74 and 1.90 Gy cm2 for 1 to <5 yr; 2.83 and 3.22 Gy cm2 for 5 to <10 yr; and 7.34 and 8.68 Gy cm2 for 10 to <16 yr, respectively. The third quartile value obtained for the DAP/body weight ratio for the full sample of procedures was 0.17 (Gy cm2/kg) for diagnostic and therapeutic procedures., Conclusions: The data presented in this paper are an initial attempt at establishing local DRLs in pediatric interventional cardiology, from a large sample of procedures for the standard age bands used in Europe, complemented with the values of the ratio between DAP and patient weight. This permits a rough estimate of DRLs for different patient weights and the refining of these values for the age bands when there may be large differences in child size. These DRLs were obtained at the largest pediatric hospital in Chile, with an active optimization program, and could be used by other hospitals in the Latin America region to compare their current patient dose values and determine whether corrective action is appropriate.

The purpose of this paper is to test the appropriateness of OSL and electronic dosemeters to estimate eye lens doses at interventional cardiology environment. Using TLD as reference detectors, personal dose equivalent was measured in phantoms and during clinical procedures. For phantom measurements, OSL dose values resulted in an average difference of -15 % vs. TLD. Tests carried out with other electronic dosemeters revealed differences up to ±20 % versus TLD. With dosemeters positioned outside the goggles and when TLD doses were >20 μSv, the average difference OSL vs. TLD was -9 %. Eye lens doses of almost 700 μSv per procedure were measured in two cases out of a sample of 33 measurements in individual clinical procedures, thus showing the risk of high exposure to the lenses of the eye when protection rules are not followed. The differences found between OSL and TLD are acceptable for the purpose and range of doses measured in the survey., (© The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background and Purpose: In 2011, the International Commission on Radiologic Protection established an absorbed-dose threshold to the brain of 0.5 Gy as likely to produce cerebrovascular disease. In this paper, the authors investigated the brain doses delivered to patients during clinical neuroradiology procedures in a university hospital., Materials and Methods: The radiation dose delivered to the brain was investigated in 99 diagnostic and therapeutic interventional neuroradiology procedures. Brain doses were calculated in a mathematic model of an adult standard anthropomorphic phantom by using the technical and radiation dose data of an x-ray biplane system submitted to regular quality controls and calibration programs., Results: For cerebral embolizations, brain doses resulted in a maximum value of 1.7 Gy, with an average value of 500 mGy. Median and third quartile resulted in 400 and 856 mGy, respectively. For cerebral angiography, the average dose in the brain was 100 mGy., Conclusions: This work supports the International Commission on Radiologic Protection recommendation on enhancing optimization when doses to the brain could be higher than 0.5 Gy. Radiation doses should be recorded for all patients and kept as low as reasonably achievable. For pediatric patients and young adults, an individual evaluation of brain doses could be appropriate., (© 2014 by American Journal of Neuroradiology.)

Despite the advent of non-fluoroscopic technology, fluoroscopy remains the cornerstone of imaging in most interventional electrophysiological procedures, from diagnostic studies over ablation interventions to device implantation. Moreover, many patients receive additional X-ray imaging, such as cardiac computed tomography and others. More and more complex procedures have the risk to increase the radiation exposure, both for the patients and the operators. The professional lifetime attributable excess cancer risk may be around 1 in 100 for the operators, the same as for a patient undergoing repetitive complex procedures. Moreover, recent reports have also hinted at an excess risk of brain tumours among interventional cardiologists. Apart from evaluating the need for and justifying the use of radiation to assist their procedures, physicians have to continuously explore ways to reduce the radiation exposure. After an introduction on how to quantify the radiation exposure and defining its current magnitude in electrophysiology compared with the other sources of radiation, this position paper wants to offer some very practical advice on how to reduce exposure to patients and staff. The text describes how customization of the X-ray system, workflow adaptations, and shielding measures can be implemented in the cath lab. The potential and the pitfalls of different non-fluoroscopic guiding technologies are discussed. Finally, we suggest further improvements that can be implemented by both the physicians and the industry in the future. We are confident that these suggestions are able to reduce patient and operator exposure by more than an order of magnitude, and therefore think that these recommendations are worth reading and implementing by any electrophysiological operator in the field., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.)

The increasing complexity and numbers of interventional fluoroscopy procedures have led to increasing patient doses of radiation and to increasing concern over staff doses. Hybrid rooms incorporate multiple imaging modalities and are used by multidisciplinary teams in interventional fluoroscopy suites and operating theaters. These rooms present additional radiation protection challenges. The new low annual exposure limit for the lens of the eye also requires specific measures to prevent cataracts in operators. The traditional attitude of radiation protection must be changed to one of proactive management of radiation dose and image quality. Incorporation of a comprehensive dose management program into the departmental quality assurance program is now essential. Physicians, radiographers, and medical physicists play an essential role in the safe use of fluoroscopy in medical practice. Efficient use of all imaging modalities (e.g., fluoroscopy, digital subtraction angiography, cone-beam CT) requires knowledge of the effects of different equipment settings on patient and staff doses as well as the skill and competence to optimize these settings for each procedure and patient. Updates and recommendations on radiation protection and dose management programs, including aspects of education and training, are presented.

The objective of this study was to perform a nationwide survey in Chile to determine dose levels to patients and staff in four risk scenarios during cardiac catheterisation procedures. Different phantom thicknesses of polymethyl methacrylate (PMMA) were used to simulate adult patients. Scenario 1: 10-min fluoroscopy and 800 cine frames for 20 cm of PMMA; Scenario 2: 10-min fluoroscopy and 800 cine frames for 28 cm of PMMA; Scenario 3: 30-min fluoroscopy and 2400 cine frames for 20 cm of PMMA; Scenario 4: 30-min fluoroscopy and 2400 cine frames for 28 cm of PMMA. The average values regarding dose-area product and scattered doses at the cardiologist eye lens achieved for the four scenarios were 94, 249, 281, 747 Gy cm(2) and 0.3, 0.8, 0.9 and 2.5 mSv, respectively. Large variations in radiation doses received by both patients and staff for the same type of procedure suggest that optimising procedure protocols and using the most effective types of protective devices may substantially reduce the dose values found here.

Objective: To present a methodology and experimental results to assess the influence, in terms of dose and image quality, of the antiscatter grid (AG) in a pediatric cardiology X-ray system., Method: Entrance surface air kerma and image quality, using a test object and different added thicknesses of polymethyl methacrylate (PMMA), for three different acquisition protocols, were measured with and without the AG, for fluoroscopy and cine modes. The image quality parameters, signal-to-noise ratio (SNR), high-contrast spatial resolution (HCSR) and two figures of merit (FOM) were evaluated., Results: The average bucky factor values measured during this experiment were 1.99, 2.49, 2.85, and 3.30, respectively for 4, 8, 12, and 16 cm of PMMA. SNR variations do not appear to be relevant when removing the AG. However, the use of AG improves HCSR significantly. Imaging the test object with 4 cm of PMMA seems appropriate without the AG, but for 8 cm (equivalent to chest thicknesses of 12 cm) and greater thicknesses, a good image quality would require the use of AG., Conclusions: The AG should not be used for neonates and very young children with chest thicknesses equal to or less than 6 cm and weight less that 6 kg., (Copyright © 2013 Wiley Periodicals, Inc.)

The radiation dose received by cardiologists during percutaneous coronary interventions, electrophysiology procedures and other interventional cardiology procedures can vary by more than an order of magnitude for the same type of procedure and for similar patient doses. There is particular concern regarding occupational dose to the lens of the eye. This document provides recommendations for occupational radiation protection for physicians and other staff in the interventional suite. Simple methods for reducing or minimizing occupational radiation dose include: minimizing fluoroscopy time and the number of acquired images; using available patient dose reduction technologies; using good imaging-chain geometry; collimating; avoiding high-scatter areas; using protective shielding; using imaging equipment whose performance is controlled through a quality assurance programme; and wearing personal dosimeters so that you know your dose. Effective use of these methods requires both appropriate education and training in radiation protection for all interventional cardiology personnel, and the availability of appropriate protective tools and equipment. Regular review and investigation of personnel monitoring results, accompanied as appropriate by changes in how procedures are performed and equipment used, will ensure continual improvement in the practice of radiation protection in the interventional suite. These recommendations for occupational radiation protection in interventional cardiology and electrophysiology have been endorsed by the Asian Pacific Society of Interventional Cardiology, the European Association of Percutaneous Cardiovascular Interventions, the Latin American Society of Interventional Cardiology, and the Society for Cardiovascular Angiography and Interventions., (Copyright © 2013 Wiley Periodicals, Inc.)

This study investigates the influence of the initial X-ray system setting on patient doses and image quality in interventional cardiology procedures. Two dedicated interventional cardiology systems were studied: a system with image intensifier (II) and a flat detector (FD) system. Entrance surface air kerma (ESAK) rates in fluoroscopy and ESAK per frame in the acquisition mode were measured on the surface of a PMMA phantom for the field of views (FOV) of 23 and 17 cm (II system) and 25 and 20 cm (FD system). Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were estimated using DICOM images obtained during the measurements. System performances were compared using a figure of merit combining SNR and ESAK. The influence of system setting on patient doses was investigated analysing the information for air kerma area product (KAP) and cumulative dose (CD) at the patient entrance reference point, for a sample of coronary angiography examinations. ESAK rates in fluoroscopy modes were a factor of 2 higher in the FD system for the similar FOVs, resulting in a factor of 1.9 higher median values of KAP and CD for patients with FD system than for the II system. SNR and CNR for the FD system were better than the equivalent FOVs with II. The resulting FOM was better for the FD system in both FOVs. Potential for optimisation was suggested by adjusting system settings.