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The work package 3 of the ORAMED project, Collaborative Project (2008-11) supported by the European Commission within its seventh Framework Programme, is focused on the optimisation of the use of active personal dosemeters (APDs) in interventional radiology and cardiology (IR/IC). Indeed, a lack of appropriate APD devices is identified for these specific fields. Few devices can detect low-energy X rays (20-100 keV), and none of them are specifically designed for working in pulsed radiation fields. The work presented in this paper consists in studying the behaviour of some selected APDs deemed suitable for application in IR/IC. For this purpose, measurements under laboratory conditions, both with continuous and pulsed X-ray beams, and tests in real conditions on site in different European hospitals were performed. This study highlights the limitations of APDs for this application and the need of improving the APD technology so as to fulfil all needs in the IR/IC field.

Some activities of EURADOS Working Group 9 (WG9) are presently funded by the European Commission (CONRAD project). The objective of WG9 is to promote and co-ordinate research activities for the assessment of occupational exposures to staff at workplaces in interventional radiology (IR) and nuclear medicine. For some of these applications, the skin of the fingers is the limiting organ for individual monitoring of external radiation. Therefore, sub-group 1 of WG9 deals with the use of extremity dosemeters in medical radiation fields. The wide variety of radiation field characteristics present in a medical environment together with the difficulties in measuring a local dose that is representative for the maximum skin dose, usually with one single detector, makes it difficult to perform accurate extremity dosimetry. Sub-group 1 worked out a thorough literature review on extremity dosimetry issues in diagnostic and therapeutic nuclear medicine and positron emission tomography, interventional radiology and interventional cardiology and brachytherapy. Some studies showed that the annual dose limits could be exceeded if the required protection measures are not taken, especially in nuclear medicine. The continuous progress in new applications and techniques requires an important effort in radiation protection and training.

Radionuclide gastric emptying studies using 99m-Tc human serum albumin egg omelette have been carried out in 10 long distance runners at rest and during a 90 minute run at sustained speed. Resting values are compared with controls comprising 10 sedentary subjects. Runners show a significantly accelerated basal gastric emptying (runners t 1/2 = 67.7 (5.9) min; sedentaries t 1/2 = 85.3 (4.5) min, p less than 0.001). The exercise had no significant effect on gastric emptying in these trained subjects (exercise t 1/2 = 66.8 (5.9) min, p = NS), suggesting adaptation to exercise.

This is the peer reviewed version of the following article: “Ginjaume, M. [et al.]. Effect of the radiation protective apron on the response of active and passive personal dosemeters used in interventional radiology and cardiology. "Journal of radiological protection, Març 2019, vol. 39, núm. 1, p. 97-111.” which has been published in final form at [doi: 10.1002/pc.23230]. This article may be used for non-commercial purposes in accordance with https://publishingsupport.iopscience.iop.org/open_access/ In fluoroscopy guided interventional procedures, workers use protective garments and often two personal dosemeters, the readings of which are used for the estimation of the effective dose; whereas the dosemeter above the protection can be used for the estimation of the equivalent dose of the lens of the eye. When a protective apron is worn the scattered field that reaches the dosemeter is different from the case where no protection is used; this study analyses the changes in the response of seven passive and eight active personal dosemeters (APDs) when they are placed above a lead or lead equivalent garment for S-Cs and x-ray diagnostic qualities. Monte Carlo simulations are used to support the experimental results. It is found that for passive dosemeters, the influence on the dosemeter's response to the lead or lead equivalent was within the range 15%–38% for the x-ray qualities. This effect is smaller, of the order of 10%, when lead-free garments are used, and much smaller, within 1%–10%, for most of the APDs used in the study. From these results it is concluded that when comparing passive and active dosemeter measurements worn above the protection, a difference of 20%–40% is expected. The effect is small when deriving the effective dose from double dosimetry algorithms, but it can be of major importance when eye lens monitoring is based on the use of the dosemeter worn above the protection.

Medical staff in interventional procedures are among the professionals with the highest occupational doses. Appropriate dosimetric follow up is very important, so that the doses can be kept as low as possible. Active personal dosemeters (APDs) can help in optimizing the exposure during the interventional procedures. However, there can be problems when using APDs during interventional procedures, due to the specific energy and angular distribution of the radiation field, and because of the pulsed nature of the radiation. Many parameters influence the occupational exposure and the scattered radiation around the patient. These include, among others, the type of interventional procedure, personal habits and working technques, protection tools used and X-ray field characteristics. In this paper, we describe the results of an experiment of EURADOS WG12. We compare the results from 3 types of APDs with a passive personal dosimetry system while being used in real clinical environment by the interventional staff. The results show that there is a large spread in the ratios of the passive and active devices. Not all results can be explained by laboratory experiments, showing that there are many parameters that influence the response of these devices.