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Patient contact shielding has been in use for many years in radiology departments in order to reduce the effects and risks of ionising radiation on certain organs. New technologies in projection imaging and CT scanning such as digital receptors and automatic exposure control (AEC) systems have reduced doses and improved image consistency. These changes and a greater understanding of both the benefits and the risks from the use of shielding have led to a review of shielding use in radiology. A number of professional bodies have already issued guidance in this regard. This paper represents the current consensus view of the main bodies involved in radiation safety and imaging in Europe: European Federation of Organisations for Medical Physics, European Federation of Radiographer Societies, European Society of Radiology, European Society of Paediatric Radiology, EuroSafe Imaging, European Radiation Dosimetry Group (EURADOS), and European Academy of DentoMaxilloFacial Radiology (EADMFR). It is based on the expert recommendations of the Gonad and Patient Shielding (GAPS) Group formed with the purpose of developing consensus in this area. The recommendations are intended to be clear and easy to use. They are intended as guidance, and they are developed using a multidisciplinary team approach. It is recognised that regulations, custom and practice vary widely on the use of patient shielding in Europe and it is hoped that these recommendations will inform a change management program that will benefit patients and staff. Patient summary [ABSTRACT FROM AUTHOR]

• Second cancer risks were assessed using patient-specific data and a mechanistic model. • fIMRT for breast cancer increases the cancer risks compared to baseline probabilities. • Hypofractionated instead of standard fractionated IMRT leads to a reduced cancer risk. To assess the risk of contralateral breast and ipsilateral lung cancer induction from forward-planned IMRT for breast carcinoma. The study group included 13 females irradiated for breast cancer with 6 MV photons. The plans were initially generated by using standard fractionated (SF) forward-planned IMRT (50 Gy at 2 Gy/fraction). Hypofractionated (HF) IMRT (42.56 Gy at 2.66 Gy/fraction) was also employed for plan creation. Differential DVHs derived from the treatment plans were used to estimate the patient-specific organ equivalent dose (OED) to the contralateral breast and ipsilateral lung and the relevant lifetime attributable risks of cancer development. These estimates were made with a non-linear mechanistic model. The radiotherapy-induced cancer risks were combined with the lifetime intrinsic risk (LIR) values for unexposed people to determine the patient- and organ-specific relative risk (RR) for second cancer induction. The OED of the contralateral breast from SF and HF forward-planned IMRT was up to 0.99 and 0.86 Gy, respectively. The corresponding values for the ipislateral lung were 4.15 and 3.66 Gy. The patient-specific RR range for the contralateral breast and ipislateral lung cancer induction following SF forward-planned IMRT was 1.04–1.10 and 1.60–1.81, respectively. The corresponding RRs from hypofractionated treatment were 1.03–1.09 and 1.53–1.73. The treatment of primary breast carcinoma with the use of SF or HF forward-planned IMRT results in increased probabilities for developing secondary malignancies in the healthy contralateral breast or ipsilateral lung compared to the respective LIRs for an unexposed population. [ABSTRACT FROM AUTHOR]

• DRLs should be a dynamic tool that follows the development of clinical practice. • A standardised approach is needed to facilitate the establishment and use of DRLs. • Dose monitoring systems can improve the cycle of establishing, updating and using DRLs. Diagnostic Reference Levels (DRLs) is an important tool that can improve radiation safety in medical imaging. However, there are certain aspects that need improvement and several obstacles that should be overcome before DRLs are fully implemented in practice. It is the authors belief that DRLs should be a dynamic tool that follows the development of clinical practice and technology advances. The establishment of adult and paediatric DRLs based on clinical indications should be considered as a priority. A common methodology and terminology is needed to allow for their clinical use. Dose monitoring systems can improve and accelerate the establishment, update and use of DRLs. However, certain steps need to be taken for proper collection. organization and analysis of big data. Availability of clinically qualified medical physicists in medical imaging departments, awareness on the importance of dose optimization and proper cooperation of relevant stakeholders are important prerequisites for the successful establishment and use of DRLs. [ABSTRACT FROM AUTHOR]

• Use, guidelines and education regarding patient contact shielding in Europe are inconsistent. • In order to reduce inconsistency of clinical use a European consensus statement is needed. • An expert group involving members of the main radiology bodies in Europe has been set up. Contact shielding has been in widespread use for the last 60–70 years aiming to protect against genetic effects, cancer, and other detriment. Since 2012, studies have begun to appear in the literature that question the continued use of such shielding, especially when radiographic technology has changed so much over the intervening period This literature has culminated in several professional bodies such as the American Association of Physicists in Medicine (AAPM) and the British Institute of Radiology (BIR) issuing guidance and statements recommending against the continued routine use of patient contact shielding. Many professional societies have also endorsed these statements. National statements on the matter continue to be produced. It is notable however that the major European bodies involved in diagnostic radiology and radiation safety have not to date issued a statement on patient shielding. This commentary looks at reasons for that and argues that it is now time for a European consensus statement on patient shielding. It is the authors belief that there are advantages to building on the work done by the AAPM and BIR, using the opportunity to amplify the statements, propagate the intent of the original statements, refine the message to deal with questions that have arisen since their publication. Α working group, Gonad and Patient Shielding (GAPS) has been formed by members from a) the European Federation of Organisations for Medical Physics (EFOMP), b) the Eurosafe Imaging initiative of the European Society of Radiology (ESR), c) the European Federation of Radiographers Societies (EFRS), d) EURADOS and e) the BIR to produce a joint statement on the proper application of patient shielding in diagnostic and interventional radiology. [ABSTRACT FROM AUTHOR]

Purpose To estimate the organ-specific probability for carcinogenesis following radiotherapy for non-malignant shoulder syndrome. Methods Photon-beam radiation therapy to 6 Gy for shoulder syndrome was simulated with a Monte Carlo code. An androgynous computational phantom representing a typical adult was used to calculate the radiation dose to out-of-field organs having a predilection for carcinogenesis. The organ-specific lifetime attributable risk (LAR) for out-of-field cancer induction was estimated by the organ dose calculations and the proper risk factors introduced by the BEIR-VII report. The average dose (D av ) and organ equivalent dose (OED) of lung, which was partially included within the treatment volume, was found from 3d-conformal radiotherapy plans. The D av and OED were used to estimate the lung cancer risk with a linear and mechanistic models, respectively. All risk assessments were made for 50- and 60-year-old male and female patients. Results Monte Carlo simulations resulted in an out-of-field organ dose range of 0.7–48.4 mGy. The LARs for out-of-field cancer induction were (1.4 × 10 −4 )% to (2.8 × 10 −2 )%. These probabilities were at least 403 times lower than the respective lifetime intrinsic risk (LIR) values. The D av and OED of lung was up to 164.9 and 142.3 mGy, respectively. The LAR for developing lung malignancies varied from 0.11 to 0.18% by the model used and the patient’s age and gender. The lung cancer risks were 36–64 times smaller than the LIRs. Conclusions The estimated probabilities for developing malignancies due to radiotherapy for non-malignant shoulder syndrome are minor relative to the natural cancer occurrence rates. [ABSTRACT FROM AUTHOR]

In this 2-part article, the authors address the need to put in perspective the risks of radiation exposure in the rapidly changing field of radiology, considering the current state of knowledge of effects at low levels. The article is based on the content of the refresher course RC 516 presented at the Radiological Society of North America's 2005 annual meeting. In part 1, the authors presented a brief review of epidemiologic studies, a discussion of typical radiation doses experienced in medicine by both patients and professionals, and the description of practical approaches to reduce unnecessary exposures. Part 2 addresses a special concern for the unborn and discusses advisory and regulatory cancer risk estimates based mainly on epidemiologic studies. The limitations of epidemiologic studies at low-level exposures and recent new findings in radiobiology, some of which are summarized, challenge the notion that any amount of radiation causes adverse effects. [ABSTRACT FROM AUTHOR]

Polymer gel dosimeters when exposed to ionising radiation increase their magnetic spin-spin relaxation rate (R2 = 1/T2) as a result of their polymerization. R2 can be measured with a variety of relaxometric MRI sequences and it is linearly correlated with the absorbed dose. The aim of this study is to compare a 2D ME-HASTE, a 2D ME-TSE and a 2D ME-SE MR sequences in 3D MRI radiation dosimetry using N-vinylpyrrolidone (VIPAR) based polymer gels. A 3D head mimicking patient phantom printed on a commercial 3D printer and 5 calibration glass vials were filled with VIPAR gel material and was irradiated to different radiation doses up to 40 Gy, using a 6 MV LINAC X-ray beam. The phantom and the vials were scanned using a 1.5 T whole body clinical scanner utilizing a 2D-ME-HASTE, a 2D-ME-TSE and a 2D-ME-SE relaxometric sequences. Correlations of R2 values with absorbed doses were estimated for all three sequences. R2 (s−1) values, measured by either 2D ME sequence, were linearly correlated to absorbed dose (Gy) for the studied dose range. (R2: mean dose sensitivity 0.08 s−1 Gy−1, r : 0.99 p < 0.005). 2D-ME-HASTE sequences revealed the best anatomical coverage for the selected irradiation volume, the best SNR and the shortest scanning time. All 2D ME relaxometric sequences can be used for 3D MRI gel dosimetry using VIPAR gels. 2D-ME-HASTE sequences hold the absolute advantage of being a fast and the most reliable solution in VIPAR MRI gel dosimetry. [ABSTRACT FROM AUTHOR]

Parturient women diagnosed with abnormal placentation are at high risk of major haemorrhage that may cause maternal death. Despite the risk of a potential damage to adjacent organs and loss of child bearing ability, hysterectomy is the gold standard technique. An alternative effective treatment technique associated with less complications and preservation of fertility is the prophylactic hypogastric artery balloon occlusion (HABO) under fluoroscopic guidance. However, concerns regarding fetal radiation exposure and the associated radiogenic risks cannot be ignored. To provide methods and data for fetal radiation dose estimation from HABO procedures. Mathematical phantoms that simulate a pregnant patient at the 9th month of gestation and Monte-Carlo-N-particle (MCNP) transport code were employed. Projection-specific normalized fetal dose (NFD) data for various beam qualities were produced through simulations of the left and right internal iliac arteries. The effects of X-ray field location relative to the fetus, field size and maternal body size on NFD were investigated. To verify MCNP results, fetal dose measurements were carried out by using a physical anthropomorphic phantom simulating pregnancy at the 3rd trimester and thermoluminescence dosimeters (TLDs). NFD was found to markedly depend on tube voltage, filtration, X-ray field location and size. Presented results have taken into account the effect of maternal body size on NFD. NFD derived from TLDs showed a difference of less than 13.5% compared to those estimated by MCNP simulations. Methods provided allow for reliable estimation of fetal radiation burden from HABO performed at any institution. This study was supported by the Greek Ministry of Education and Religious Affairs, General Secretariat for Research and Technology, Operational Program 'Education and Lifelong Learning', ARISTIA (Research project: CONCERT). [ABSTRACT FROM AUTHOR]

Head radiography comprises a common examination protocol in clinical routine. Diagnostic decisions are associated with the detected injuries. Consequently, image quality of the x-ray examinations is essential for the early diagnosis and appropriate treatment, especially for the sensitive population of children. Therefore each examination protocol should be appropriately optimized to achieve images of high diagnostic quality and minimum radiation burden to patients. To optimize the radiographic technique for head examination protocols in pediatric patients. Three anthropomorphic phantoms (ATOM Phantoms, CIRS, Norfolk, VA) representing the average individual as neonate, 5-year-old, and 10-year-old child were employed. The phantoms were subjected to head radiographs using a state of the art digital radiographic system (AGFA GAEVART, DX-D600) for various tube voltages (50–125 kVp) and current settings (0.2–50 mAs). For each exposure, image quality objective parameters, including contrast to noise ratio values (CNR) were estimated to determine figure of merit (FOM) in the optimization process. The technique associated with the higher CNR value for the same FOM was considered as the optimized method. Dose reduction of up to 88% was recorded for the same CNR value when decreasing tube voltage. CNR was found to be improved decreasing tube voltage for all ages of pediatric phantoms. However, due to larger exposure time, motion artifacts may be conspicuous. A reliable optimization methodology for head radiographs in pediatric patients was presented. The method described may be also applied in other anatomical regions. [ABSTRACT FROM AUTHOR]

Abstract: Aim: To evaluate the potential of SPECT myocardial perfusion imaging (MPI)–computed tomography coronary angiography (CTCA) hybrid fusion imaging to improve the diagnostic performance of cardiac SPECT/MPI and CTCA alone in order to act as more accurate gate keeper to further investigation invasive or not. Methods and results: Twenty-five patients were subjected to SPECT/MPI and CTCA within a period of 1 month without any medical treatment modification. A fusion software package was used for cardiac SPECT–CTCA image fusion. Semiquantitative analysis was performed for cardiac SPECT, CTCA and SPECT/MPI–CTCA fusion images. Patients were classified in 2 groups according to the clinical decision for further investigation (group A), or not (group B). Statistically significant differences were observed when SPECT/MPI–CTCA fusion images were used instead of cardiac SPECT alone (p <0.05). No statistically significant differences were observed comparing CTCA alone to SPECT/MPI–CTCA fusion images (p =0.25). A mid-term follow-up (mean 3.58±0.24 years) showed that all patients classified in group A based on the interpretation of SPECT MPI–CTCA fused images underwent conventional coronary angiography with further necessity for PTCA or CABG whereas absence of major or minor cardiac events was revealed for all patients of group B. Conclusion: In patients suspected for coronary artery disease, cardiac SPECT/MPI–CTCA fusion imaging was found to considerably alter the clinical decision for referral to further investigation derived from SPECT/MPI. [Copyright &y& Elsevier]

Abstract: Aims: To measure the testicular and ovarian doses and to assess the risk for gonadal damage to patients treated with megavoltage X-ray beams for benign diseases. Materials and methods: Radiation therapy of benign diseases was simulated on an anthropomorphic phantom with a 6MV photon beam. The gonadal dose was calculated during the irradiation of heterotopic ossification, liver and vertebra haemangiomas, bone cysts, Graves'' ophthalmopathy and gynaecomastia. Dose measurements were carried out using thermoluminescent dosimeters. For the radiotherapy of heterotopic ossification, the effect of using lead blocks to spare lymphatic drainage on the gonadal dose was determined. Results: The ovarian and testicular total doses were found to be 2.00–680 and 2.0–39.0mGy, respectively, depending on the gonadal location in respect to the treatment volume. The introduction of blocks into the primary beam resulted in an increase in gonadal dose up to a factor of 1.7. The radiation-induced risk of hereditary disorders in future generations was (1.0–40.8)×10−4 and (1.0–23.4)×10−4 for women and men, respectively. Conclusions: Radiation therapy of benign diseases always resulted in gonadal doses below 1Gy and therefore there was no risk for permanent gonadal failure. The excess risk of radiation-induced hereditary disorders in offspring was low in comparison with the natural frequency of these effects. However, there was a considerable excess in risk after irradiation in the hip bone. [Copyright &y& Elsevier]