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• Online mentoring is useful to support young professionals in developing countries. • The impact of a global mentoring program on career development of young medical physicists was evaluated. • The mentor-mentee relationship can be helpful in decision-making situations. • Mentoring relationships can incentivise and promote the development of leadership. Mentoring aims to improve careers and create benefits for the participants' personal and professional lives. Mentoring can be an individual or a shared experience for a group, while the mentor's role remains the same in both models. Mentors should increase confidence, teach, inspire, and set examples, helping the mentees to mould their path, contributing to the pursuit of their personal and professional goals. This study aims to report on the experience of early-career medical physics professionals and postgraduate students participating in a global mentoring program and to assess the impact of this activity on their professional development. The objectives of this mentoring program are to develop leadership roles among young medical physicists and to provide guidance and support. An online questionnaire was administered to the mentee participants. The analysis of their responses is reported in this work and the current status of the programme was examined using a SWOT analysis. In general, the mentoring experience had a positive impact on the mentees. The mentors were found especially helpful in the decision-making situations and in other conflicts that may arise with career development. Additionally, the mentees felt that mentoring contributed to the development of leadership skills required for the job market and assist in personal development. This paper concludes that participation of young medical physicists in a mentoring group program is beneficial to their career and therefore should be encouraged. [ABSTRACT FROM AUTHOR]

• Dose management software (DMS) facilitated analysis of clinical and technical parameters. • DMS facilitated evaluation of radiographers' performance. • DMS disclosed the role of medical physicist in dose management and optimization. • Typical values for screening and diagnostic mammography and for various compressed breast thicknesses were defined. This work aimed to evaluate the use of a dose management software (DMS) in mammography and analyse the clinical practice in terms of radiation exposure in screening and diagnostic mammography. Mean glandular dose (MGD) from approximately 10,000 images were collected and analysed taking into account anode/filter combination, projection, compressed breast thickness (CBT) and compression force. Causes of increased MGD were investigated and actions were taken when malpractice was detected. MGD values for craniocaudal (CC) and mediolateral oblique (MLO) exposures for different CBT were defined. The average MGD for CBT of 60–69 mm was 1.84 mGy for CC images and 1.85 mGy for MLO images for screening examinations, while for diagnostic examinations the MGD was 1.95 mGy for CC and 2.01 mGy for MLO images. As no national diagnostic reference levels (DRLs) for mammography exist in Switzerland, typical mean glandular dose (MGD) values were defined as a first step towards their establishment for both screening and diagnostic examinations. The use of DMS facilitated immensely the analysis of all clinical and technical parameters, the evaluation of radiation dose received by the patients, as well as the overall evaluation of radiographers' performance. The DMS disclosed the role of the medical physicist in dose management and optimization. [ABSTRACT FROM AUTHOR]

• Digital cholangioscopy (DA) with ERCP is associated with much shorter fluoro time. • DA with ERCP is associated with substantially lower radiation dose. • DA with ERCP is a radiation-sparing alternative to ERCP for complex choledocolithiasis. Endoscopic Retrograde Cholangio-Pancreatography (ERCP) is an well-established endoscopic procedure for the management of biliary diseases. The use of fluoroscopy during ERCP has often raised concerns regarding potential risks from radiation exposure, particularly in complex cases. We investigated whether a new digital single-operator cholangioscopy (D-SOC) system, used adjunctively to ERCP, actually reduces patient radiation exposure. We retrospectively analyzed a prospective database (April 2016 to October 2018) including consecutive patients who underwent successful management of difficult-to-treat biliary stones or indeterminate biliary strictures by using either conventional ERCP (ERCP cohort) or ERCP in conjunction with D-SOC (ERCP/D-SOC cohort). The overall patient radiation exposure outcomes were compared in terms of Kerma Area Product (KAP), Fluoroscopy time (T) and the total number of films (F). Overall, 47 patients (mean 71.8 years, 59.6% males) were included (ERCP cohort = 29, ERCP/D-SOC cohort = 18), referred either for difficult bile duct stones (n = 36) or indeterminate biliary strictures (n = 11). The median KAP, T and F in the ERCP/D-SOC cohort were 12.3 Gycm2, 3.7 min and 4 films respectively, compared with 52.1 Gycm2, 8.4 min, and 5 films respectively in the ERCP cohort. Statistically significant differences (P = 0.0001) were found for KAP and T. Adjunct use of a digital cholangioscopy platform appears to significantly reduce radiation exposure in patients undergoing ERCP for the management of difficult bile stones or indeterminate biliary strictures. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate paediatric radiation doses in a dedicated cardiology hospital, with the objective of characterising patterns in dose variation. The ultimate purpose was to define Local (Institutional) Diagnostic Reference Levels (LDRLs) for different types of paediatric cardiac interventional procedures (IC), according to patient age. From a total of 710 cases performed during three consecutive years, by operators with more than 15 years of experience, the age was noted in only 477 IC procedures. The median values obtained for Fluoroscopy Time (FT), Number of Frames (N) and Kerma Area Product (P KA ) by age range were 5.8 min, 1322 and 2.0 Gy.cm 2 for <1 y; 6.5 min, 1403 and 3.0 Gy.cm 2 for 1 to <5 y; 5.9 min, 950 and 7.0 Gy.cm 2 for 5 to <10 y; 5.7 min, 940 and 14.0 Gy.cm 2 for 10 to <16 y, respectively. A large range of patient dose data is observed, depending greatly on procedure type and patient age. In all age groups the range of median FT, N and P KA values was 3.1–15.8 min, 579–1779 and 1.0–20.8 Gy.cm 2 respectively. Consequently, the definition of LDRLs presents challenges mainly due to the multiple clinical and technical factors affecting the outcome. On the other hand the lack of paediatric IC DRLs makes the identification of good practices more difficult. A consensus is needed on IC procedures nomenclature and grouping in order to allow a common assessment and comparison of doses. [ABSTRACT FROM AUTHOR]

Dental radiology uses X-ray technology to diagnose and design treatment of various clinical problems related to the oral cavity and surrounding tissues. As technology quickly evolves, there are numerous X-ray modalities using different tools in the attempt to best image and treat efficiently these diseases, disorders or other related clinical conditions. The reported numbers of dental X-rays, the fact that these may be under-reported in many countries and because dental X-rays are performed more on younger individuals, whose teeth and dentition are still developing, calls for increased need on radiation protection. The objectives of this paper are to report on the latest technology updates and related radiation protection issues, to present future directions and define gaps. Most of existing radiation protection national and international guidelines are more than a decade old. Update is needed to account for newer technologies such as cone beam computed tomography (CBCT) and digital imaging. Diagnostic Reference Levels (DRLs), a well established method for dose optimization, are not yet defined for CBCT and have to be set for various clinical indications. As far as shielding is concerned, recent data confirm that use of lead apron, even in pregnant patients, or gonadal shielding are not recommended, due to negligible radiation dose reduction. Thyroid lead shielding should be used in case the organ is in or close to the primary beam. Specifically for CBCT, leaded glasses, thyroid collars and collimation (smaller field of view (FOV) especially for paediatric patients) minimize the dose to organs outside the FOV. [ABSTRACT FROM AUTHOR]

The main objective of this study was to determine the preliminary Diagnostic Reference Levels (DRLs) in terms of Kerma Area Product (KAP) and fluoroscopy time (Tf) during Endoscopic Retrograde Cholangio-Pancreatography (ERCP) procedures. Additionally, an investigation was conducted to explore the statistical relation between KAP and Tf. Data from a set of 200 randomly selected patients treated in 4 large hospitals in Greece (50 patients per hospital) were analyzed in order to obtain preliminary DRLs for KAP and Tf during therapeutic ERCP procedures. Non-parametric statistic tests were performed in order to determine a statistically significant relation between KAP and Tf. The resulting third quartiles for KAP and Tf for hospitals (A, B, C and D) were found as followed: KAP A = 10.7 Gy cm 2 , Tf A = 4.9 min; KAP B = 7.5 Gy cm 2 , Tf B = 5.0 min; KAP C = 19.0 Gy cm 2 , Tf C = 7.3 min; KAP D = 52.4 Gy cm 2 , Tf D = 15.8 min. The third quartiles, calculated for the total 200 cases sample, are: KAP = 18.8 Gy cm 2 and Tf = 8.2 min. For 3 out of 4 hospitals and for the total sample, p -values of statistical indices (correlation of KAP and Tf) are less than 0.001, while for the Hospital A p -values are ranging from 0.07 to 0.08. Using curve fitting, we finally determine that the relation of Tf and KAP is deriving from a power equation (KAP = Tf 1.282 ) with R 2 = 0.85. The suggested Preliminary DRLs (deriving from the third quartiles of the total sample) for Greece are: KAP = 19 Gy cm 2 and Tf = 8 min, while the relation between KAP and Tf is efficiently described by a power equation. [ABSTRACT FROM AUTHOR]

Objective To investigate skin dose in Computed Tomography (CT) and its dependence on scanning geometry. Materials and methods Measurements of entrance surface air kerma (ESAK) in free air and entrance skin dose (ESD) on an anthropomorphic phantom were performed in a 64-slice CT scanner, using two different instruments: the Dose Profiler (DP) and the QED skin diode (QEDSD). Using DP and QEDSD, the ESAK rate profiles at the isocenter and at different distances from it, were measured using axial scans. Using DP and helical scans the ESAK rate profile in the Z-axis was acquired. The same profile was acquired with the QEDSD also, using many axial scans and manual table translation. ESD measurements were performed with the DP and QEDSD, in axial and helical scan mode. Results ESAK measurements with DP and QEDSD were in good agreement, for both point dose and profile measurements. The agreement was also good for ESD measurements but not for helical scans, due to variable X-ray beam overlapping and different tube angular positions at each scan start. It was observed that the ESD values at different Y-axis offsets were comparable to the respective ESAK values recorded at the same Y-axis offset distances without the phantom. Conclusions Both DP and QEDSD were proven suitable for performing point ESD measurements. However, calculating the skin dose distribution in CT examinations is a very challenging task. A practical approach would be for CT scanners to provide a conservative estimate of the peak skin dose using the isocenter ESAK value. [ABSTRACT FROM AUTHOR]

Purpose To estimate the mean glandular dose of contrast enhanced digital mammography, using the EGSnrc Monte Carlo code and female adult voxel phantom. Methods Automatic exposure control of full field digital mammography system was used for the selection of the X-ray spectrum and the exposure settings for dual energy imaging. Measurements of the air-kerma and of the half value layers were performed and a Monte Carlo simulation of the digital mammography system was used to compute the mean glandular dose, for breast phantoms of various thicknesses, glandularities and for different X-ray spectra (low and high energy). Results For breast phantoms of 2.0–8.0 cm thick and 0.1–100% glandular fraction, CC view acquisition, from AEC settings, can result in a mean glandular dose of 0.450 ± 0.022 mGy −2.575 ± 0.033 mGy for low energy images and 0.061 ± 0.021 mGy – 0.232 ± 0.033 mGy for high energy images. In MLO view acquisition mean glandular dose values ranged between 0.488 ± 0.007 mGy – 2.080 ± 0.021 mGy for low energy images and 0.065 ± 0.012 mGy – 0.215 ± 0.010 mGy for high energy images. Conclusion The low kV part of contrast enhanced digital mammography is the main contributor to total mean glandular breast dose. The results of this study can be used to provide an estimated mean glandular dose for individual cases. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To calculate the cumulative effective and skin doses in patients that underwent repeated CT guided radiofrequency ablations (RFA). Materials and methods: From all patients that had undergone RFA during a five years period those which had three or more RFAs were selected. Using the CT images DICOM data, the dose length product (DLP), effective dose (E), skin dose profiles as well as the peak skin dose (PSD) were calculated, using appropriate methods and software developed for this purpose. For each patient, cumulative DLP and E were also calculated from the sum of the respective figures of each individual procedure. To calculate PSD, the skin dose profiles of each procedure were overlaid on the same Z-axis scale using anatomical landmarks for reference and the skin doses to each point were summed up. Results: Five patients were studied; four had undergone 3 RFAs and one 10 RFAs. Cumulative DLP, E and PSD ranges were 5.6–22.3 Gy cm, 0.08–0.36 Sv and 0.8–3.4 Gy, respectively. Median E and PSD values per RFA were 35 mSv and 0.4 Gy, respectively. For comparison purposes it must be noted that in this CT department a routine abdomen-pelvis scan results to an E of about 10 mSv. Conclusions: Patients that undergo repeated RFAs are exposed to considerably high radiation exposure levels. When these patients are in the final stage of malignant diseases, stochastic effects may not be of major concern. However, optimization of the exposure factors and monitoring of these patients to avoid skin injuries are required. [Copyright &y& Elsevier]

Objective: To investigate the impact of X-ray preset acquisition protocol settings on fluoroscopy image quality (IQ) and radiation exposure.Materials& Methods: A quality control (QC) phantom was imaged with a modern digital C-arm system, using various preset fluoroscopy protocols. IQ was assessed using human observers and in-house software for automated evaluation, based on contrast-to-noise ratios of details and their background. Patient radiation exposure was evaluated using the displayed Incident Air-Kerma and Kerma-Area Product values.Results: Protocol selection affects radiation exposure by a factor of about 3. IQ evaluation showed that acquisition protocols produce images with quite different characteristics. The visual IQ evaluation method was time consuming and cumbersome. The automated method, utilized the visual IQ evaluation results for calibration of detection thresholds. However, it failed to reproduce these results for all images and details types. In some images, digital image processing created artifacts which affected the pixel value distributions around details in a way that could be handled only by the human vision.Conclusion: Manufacturers provide many preset protocols designated for specific clinical uses, which have large impact on IQ characteristics and radiation exposure. However, protocol settings' selection rationale is essentially a "black box" for the end user. Though QC phantoms are currently used for IQ evaluation, they are not appropriate for drawing firm conclusions concerning the expected performance of each protocol in clinical practice. Currently, there is no consensus on the optimum technical characteristics of preset protocols for specific procedures. More work is needed in this area. [ABSTRACT FROM AUTHOR]

There are many types of medical imaging procedures that are applied on children. Imaging has to take into account the dynamics of a growing body, from pre-term infants to large adolescents. CT imaging, currently the gold standard in the detection of certain pathologies, imparts the highest radiation dose to children. The purpose of the study was to identify the main pathologies for which CT is applied and related radiation doses as reported in the literature in order to facilitate justification and CT optimization. A critical analysis of a literature review was performed. Different search engines were used such as PubMed, Google Scholar and Science Direct. Various terms and keywords were used to locate pertinent articles such as Pediatric, Computed tomography, CTDI, DLP, Radiation Dose, Organ dose, Effective dose. The results showed that the main pathologies for which CT is applied are: Crohn's disease, hydrocephalus, cystic fibrosis and pediatric malignancies - mainly lymphoma. The related radiation dose data are extremely scarce and are in the range of 1–25 mSv, 0.2–15.3 mSv, 0.14–6.2 mSv, and 5–528 mSv, respectively. The radiation doses reported are high especially in pediatric oncology. Pediatric patients are exposed to high levels of radiation during CT imaging. Literature is lacking reporting of dose in Pediatric CT imaging. More studies need to be realized for the determination of radiation dose in those patients. Special protocols need to be recommended in order to reduce the exposure of children in radiation. No Disclosure. [ABSTRACT FROM AUTHOR]

In breast, the glandular tissues are of high sensitivity to radiation and for this reason the mean dose to the glandular tissues is the most suitable dosimetric quantity. According to the IAEA protocols the Mean Glandular Dose (MGD) is derived from measurements of the incident Air Kerma at the surface of phantom and of the HVL, using tabulated conversion coefficients. Disadvantage of the method is the fact that for calculations use a very simple model of the breast. The purpose of this study is to assess the mean glandular dose in breast using Monte Carlo code and voxel phantoms in standing posture. Fifty different phantoms (breast's thickness from 2 to 8 cm for both CC and MLO modes and for glandular fractions in the range of 1.0–100%) and EGSnrc Monte Carlo code was used to calculate the interaction of photons with matter and estimate the MGD to the breast. The calculations were made for the x-ray spectra from a Mo target (tube voltage range 26–32 kV) filtered by Rh. For breast phantoms of 2.0–8.0 cm thick and 0.1–100% glandular fraction CC view acquisitions can result in a MGD of 0.452–2.572 mGy. In MLO view acquisitions MGD values ranged between 0.486 and 2.089 mGy. MGD is decreased with increasing glandularities and with increasing breast thickness in general. The voxel phantoms is a powerful tool for the study of breast dosimetry. When there is some knowledge of the distribution of glandular tissue within the breast, the results of this study can be used to provide for individual cases. [ABSTRACT FROM AUTHOR]

Multi detector CT (MDCT) X-ray systems provide high quality paediatric imaging. However, the last years, concern has been expressed on radiation exposure to children. Very few surveys depicting paediatric exposure from MDCT s are available. To shape the status of radiation dose in children from MDCT practice in a dedicated paediatric hospital in Greece. This was a retrospective study in a 160 bed paediatric hospital equipped with a Philips Brilliance 16 CT scanner installed in 2010. Patient data and acquisition parameters were recorded for CT studies of head, abdomen, chest and spine and were divided in three age groups (1–5 years, 5–10 years, 10–15 years). The dosimetric results were reported in terms of volumetric CT dose index (CTDIvol) (mGy), dose length product (DLP) (mGycm), and total DLP for multiphase studies. The results were compared with adult national DRLs and paediatric European published data. Data were collected from 97 MDCT examinations and included 39 head CTs, 12 abdomen CTs, 20 chest CTs and 26 spine CTs. Acquisition parameters used were according to age for head CTs and weight-dependent for the other scans. Spiral or axial scan depended on anatomic area and on the radiologist on duty. Multiphase studies accounted for 10% of patient sample, 80% of these in the abdomen region. For the three age groups, CTDIvol, DLP and total DLP average values were significantly lower than adult national DRLs, although they increased with age, and were in accordance with published paediatric European data. Initial data showed that use of protocols tailored to patient's age or weight results in significant dose reduction. Use of standardized CT protocols should be encouraged. [ABSTRACT FROM AUTHOR]

New applications of CT are still shown, the most prominent example of which is the development of Cone Beam Computed Tomography (CBCT) for dental and maxillofacial imaging. The majority of studies related to CBCT dental radiation dose are based on anthropomorphic phantoms. Patient clinical studies on radiation dose are still scarce. The purpose of this study was to measure patient radiation exposure in terms of Kerma Area Product (KAP) and effective dose (Ef) in implant dentistry. The X-ray system used was a CS 9300 Carestream system. Patient sample included 177 individuals undergoing one or more CBCT examinations. Data recorded included: KAP, tube voltage (kV), tube current (mA), exposure time (s), field of view (FOV), patient age (A) and clinical indication. Patient sample mean age was 56 years. Women were 52.5% and men 47.5%. Patients had either 1 (80.2%), 2 (14.7%), 3 (2.35%) or >3 (2.3%) CBCT exams. Protocol details were: 80–90 kV, 4–5 mA, 8 s and a fixed FOV of 10 × 10 cm2. Mean ± sd KAP was 523 ± 119 mGycm2. A conversion factor of 0.08 mSv/Gycm2 was used to calculate Ef. Mean ± sd Ef was 42.4 ± 9.6 μSv. A coarse comparison was done with international data from phantom studies. This showed that our results were at the low part of the dose range reported in the international literature The radiation dose values presented provide a baseline for future reference. More clinical studies are needed in order to derive more robust results on radiation dose levels in dental CBCT. Authors should disclose any relationship that may bias their presentation. Please enter disclosure information here. [ABSTRACT FROM AUTHOR]

3D breast imaging using the technique of digital tomosynthesis may have the ability to improve the visualization of tissues which would be superimposed on a conventional mammogram. Early results with digital tomosynthesis are promising. To estimate mean glandular dose (MGD) from tomosynthesis imaging of the breast using Monte Carlo code and voxel phantom in standing posture. EGSnrc Monte Carlo code was used to simulate the interaction of photons with matter included a female voxel phantom (breast thickness of 2-8 cm and 50% glandular fraction). For the selection of X-ray spectrum, Automatic Exposure Control of Digital Breast Tomosynthesis was used. For each imaging condition were computed the glandular dose for the zero degree projection angle and the glandular dose for non-zero projection angles in 2° steps (scan range was −25° to +25°). The calculations were made for the X-ray spectra from a W target (tube voltage range 25–40 kV) filtered by Rh. Acquisition of a cranio-caudal view resulted in an MGD ranging from 0,318 to 2,347 mGy. For a breast with a thickness of 5 cm and 50% glandular fraction, the MGD was 2.061 mGy. There is no significant difference between the MGD for CC and MLO mode. The results of this study are limited to providing the MGD to voxels phantoms of various thickness and only 50% glandular fraction. Future studies of the resulting dose from various glandular fractions are needed. [ABSTRACT FROM AUTHOR]

Atrial septal defect (ASD) is an abnormal opening in the wall between the two atrias of the heart. A catheter-based treatment in a heamodynamic room is a well established procedure. International literature has extremely limited data on related radiation dose levels. To determine radiation dose (RD) fluoroscopy time (FT) and Number of images (I) in ASD treatment in both paediatric and adult patients in a major cardiosurgery center in Greece. A sample of 161 patients were included in the study, divided in the following age categories: (1) 5–10 y, (2) 10–15 y, (3) 15–18;y and (4) >18 y. The X-ray machine used was a Siemens Artis Zee digital flat panel system. Various clinical (weight, body mass index, (BMI), etc.) and radiation related data (Kerma Area Product (KAP), fluoroscopy time (T) and number of images (F)) were recorded. Median W (kg), BMI (kg/m2), KAP (Gycm2), T (min) and F for the 4 weight categories were: (1) 25, 15.5, 5.8, 6.6 and 639, (2) 50, 21.5, 9.3, 4.6 and 409 (3) 58.5, 21.2, 11.6, 5.7 and 575 and finally (4) 58.0, 19.5, 5.8, 3.2 and 639. The correlation of various factors with KAP was investigated. Apart from fluoroscopy time there was no other factor that significantly correlated with radiation dose. This study presents age-stratified radiation data for ASD occluder heart catheterizations. Fluoroscopy time or number of images are not adequate measures for monitoring radiation exposure. These values will be used as baseline for our future research on the subject. [ABSTRACT FROM AUTHOR]

The article presents abstracts on topics related to positron emission tomography (PET) and molecular imaging, including the association between myocardial oxidative consumption and exercise tolerance in patients with chronic heart failure, the effects of using matrix metalloproteinase-9 gene deletion on angiogenesis following myocardial infarction and the feasibility of using L-3-[C-11] lactic acid (C11-LA) in measuring myocardial lactate oxidation by PET and kinetic modeling.