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In the framework of the ORAMED project (Optimization of RAdiation protection for MEDical staff), funded by the European Union Seventh Framework Programme, different studies were aimed at improving the quality of radiation protection in interventional radiology and nuclear medicine. The main results of the project were presented during a final workshop held in Barcelona in January 2011, the proceedings of which are available in the open literature. One of the ORAMED tasks was focused on the problem of eye-lens photon exposure of the medical staff, a topic that gained more importance especially after the ICRP decision to lower the limiting equivalent dose to 20 mSv per year. The present technical note has the scope, besides briefly summarising the physical reasons of the proposal and the practical implications, to provide, in tabular form, a set of air kerma to Hp(3) conversion coefficients based on the adoption of a theoretical cylindrical model that is well suited for reproduction of the mass and the shape of a human head. © The Author 2012. Published by Oxford University Press. All rights reserved.

In the framework of the ORAMED project (Optimization of RAdiation protection for MEDical staff), funded by the European Union Seventh Framework Programme, different studies were aimed at improving the quality of radiation protection in interventional radiology and nuclear medicine. The main results of the project were presented during a final workshop held in Barcelona in January 2011, the proceedings of which are available in the open literature. One of the ORAMED tasks was focused on the problem of eye-lens photon exposure of the medical staff, a topic that gained more importance especially after the ICRP decision to lower the limiting equivalent dose to 20 mSv per year. The present technical note has the scope, besides briefly summarising the physical reasons of the proposal and the practical implications, to provide, in tabular form, a set of air kerma to Hp(3) conversion coefficients based on the adoption of a theoretical cylindrical model that is well suited for reproduction of the mass and the shape of a human head.

This communication summarizes the results concerning the Monte Carlo (MC) modelling of Germanium detectors for the measurement of low energy photons arising from the International comparison on MC modelling for in vivo measurement of Americium in a knee phantom organized within the EU Coordination Action CONRAD (Coordinated Network for Radiation Dosimetry) as a joint initiative of EURADOS working groups 6 (computational dosimetry) and 7 (internal dosimetry). MC simulations proved to be an applicable way to obtain the calibration factor that needs to be used for in vivo measurements.

In recent years voxel models have been used to investigate the validity of radiation protection quantities evaluated, till now, employing stylized reference models. An ICRP task group (DOCAL) is developing a male and female reference voxel models to estimate a new set of radiation protection quantities. It should be taken into account that, due the intrinsic subject-dependent anatomical differences, the various developed voxel models can imply a certain variability in the corresponding sets of estimated conversion coefficients. Therefore a qualitative evaluation of the range of such discrepancies should be of interest in terms of the sensitivity of organ absorbed dose to the specific model used for its computation. The NORMAN-05 model, updated at ENEA-Radiation Protection Institute on the basis of the original NORMAN model, developed by P. Dimbylow at NRPB-UK (now HPA) in the 1990s, is a good representation of the standard Caucasian-type man and could be a valuable tool for comparison with other voxel models in order to state the inherent uncertainties associated to the estimated sets of conversion coefficients. The present paper summarizes the results obtained with NORMAN-05 and the Monte Carlo code MCNPX for neutron conversion coefficients calculation, in the energy domain from thermal to 20 MeV, in the kerma approximation that, for such energy range, as stated in the ICRU/ICRP recommendations, is a satisfactory approach.

It was the purpose of the study to evaluate morcellized bone with cement and antibiotic release mixed with vancomycin and methylmethacrylate cement (PMMA). The aim of the study is part of a wider one aimed at verifying the possibility of using this composite for the treatment of chronic septic pathologies of the bone. Five cylinders 1 cm in height by 1 cm in diameter, formed by morcellized bone with cement and vancomycin were immersed in plasma and 5 in physiological solution. Three cylinders equal in size but formed by cement and antibiotic alone were immersed in plasma and 3 in physiological solution. All of the cylinders remained in immersion for 28 days at a temperature of 37 degrees C. The immersion fluids were changed every day during the first week and on days 14, 21 and 28. The quantity of vancomycin released was dosed in each specimen. The greatest and most constant release of antibiotic took place in the cylinders of morcellized bone, cement and antibiotic immersed in plasma.

To design a new radon gas dosemeter, Monte Carlo simulation has been used to determine the response of the device, fitted with a CR-39 SSNTD, to the different geometric conditions associated with the progress of the holder. The a counting efficiency of a SSNTD depends primarily on the energy and incidence angle into the detector, then on the etching conditions and finally on the track counting procedure. Therefore the elicited efficiency function represents all these factors. The detectors were exposed to a particles at different angle incidences and energies, by using a 244Cm source; two alternative NaOH solution etching conditions were tested, respectively 6 h and 12 h, at 70 °C and 6,5 N. The counting was performed with a light microscope, 267 X, and with an automatic track analysis procedure.

The medical staff performing interventional cardiology and radiology (IC/IR) procedures stand close to the patient and thus close to the primary radiation beam. Although they wear a lead apron and thyroid collar, their hands, legs and eyes are not protected. Therefore, these parts could receive significantly high doses. Moreover, thedose ranges for the same kind of procedures vary a lot, as many factors affect extremity and eye lens doses. Additionally, there is evidence that eye lens doses can be high in IR/IC, and cases of cataract have been reported in recent years. A lack of an appropriate eye lens dosemeter as well as an appropriate calibration procedure has been identified. Medical staff in IR/IC could benefit from the use of active personal dosemeters (APDs) as optimisation tool. However, a lack of appropriate APDs is identified for typical fields in IR and IC. Very few devices can detect low energy fields, and none of them are really designed for working in pulsed radiation fields. In the field of nuclear medicine (NM) the extremity doses to the technologists are also known to be very high. One can highlight the difficulties in estimating the dose distribution across the hands, and the need for greater knowledge of doses received during the main tasks of a nuclear medicine department, especially using unsealed sources. The ORAMED project, (www.oramed-fp7.eu) was set up to optimize the working procedures in these medical fields with respect to radiation protection. ORAMED wasstructured in 5 work packages: - Extremity and eye lens dosimetry in IR and IC - Development of practical eye lens dosimetry - Optimization of the use of APDs in IR and IC - Extremity dosimetry in NM - Training and dissemination A coordinated measurement program in European hospitals was organised both in IR/IC and NM departments. Moreover, simulations of the most representative workplaces/procedures were performed to determine the main parameters that influence the extremity and eye lens doses. Some dedicated studies on improving the eye lens dosimetry and active personal dosimetry were conducted. Based on the measurement and simulation results, a series of practical guidelines and training packages were developed. The influence of the different radiation protection measures (like shields)in IR/IChave been quantified, and clear monitoring requirements have been formulated for a series of medical procedures. A formalism for the use of the operational quantity for eye lens dose measurements have been worked out (calibration phantom, conversion coefficients, type test procedures, ...). A dedicated eye lens dosemeter has been developed that can be used in routine monitoring. The different existing APDs have been tested in fields that are representative for hospital fields (like pulsed fields), and a series of guidelines for the use of these APDs in hospitals have been made. Also, an improved APD device specifically for IR/IC fields has been developed.The extensive measurement and simulation campaign for extremity doses in NM lead to a systematic evaluation of the different radiation protection measures. These are condensed in a series of practical guidelines to be used. The dose distribution across the hands of the technologists was characterised, and recommendations for routine monitoring have been formulated. The outcome of the ORAMED project will improve the radiation protection standards for medical staff. The systematic measurements and simulations are the new standards that will be used for many years to come. The practical guidelines that have been developed can be used in the hospitals by the medical staff. In particular, the developments on the eye-lens dosimetry and the active personal dosemeters will result in an improvement of the practical measurement capabilities in the field.