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Detailed measurements of exposure to electromagnetic radiation of the population of Neapoli-Sykies area
Abstracts / Physica Medica 32 (2016) 274–283
Purpose. Our goal was to validate this guideline and to investigate whether we could advise for or against some specific recommendations. Materials and methods. Between 2009 and 2016, 56 patients with CIEDs were treated in our institution. Dose to the CIED was assessed for every patient who was classified according to his risk. Patients were evaluated before, during and after radiotherapy by a cardiologist following guideline recommendations. Results. Our patient focus group consisted of 39, 15 and 1 patients categorized into low, medium and high risk groups, respectively. The median age was 75 (range 54–98) years. Most treatments were prostate primaries (20%), brain metastasis (16%), head and neck primaries (9%) lung primaries (7%), and esophagus (5%). The prescribed dose ranged from 8 to 78 Gy with a daily dose ranging from 1.8 to 8 Gy. The maximum doses to the CIEDs were 179.1 cGy, 751 cGy and 1270 cGy, for the low, medium and high risk groups, respectively. Radiation therapy was safely delivered in all patients. Conclusion. Our data support the fact that radiation dose seems to play a lesser role in inducing CIEDs malfunctions. Beam energy appears to be the essential factor in inducing these damaging effects according to the literature. Based on our work the following suggestions could be advocated: inactivation of antitachycardia therapies during RT as well as heart rhythm monitoring seems to be redundant and photon beam energy should be limited to 610 MV. http://dx.doi.org/10.1016/j.ejmp.2016.07.605
A METHOD FOR ASSESSING THE DOSIMETRIC CONSISTENCY OF SINGLE PHASE 4DCT DOSE ACCUMULATION BASED ON DEFORMING IMAGE REGISTRATION Flavio Enrico Nelli, Jeffrey Roy Harwood * Andrew Love Cancer Centre, University Hospital Geelong, Geelong, VIC, Australia ⇑ Corresponding author. Introduction. The interplay effect in FFF-VMAT SBRT deliveries can produce clinically relevant discrepancies between planned and delivered doses to moving targets. To assess the impact of motion on treatment delivery, dose distributions calculated on each phase of a 4DCT scan can be accumulated in a single phase using deforming image registration (DIR). The use of this technique as a treatment quality assurance tool requires dosimetric validation. Purpose. To develop a method for assessing the accuracy of DIRbased dose accumulation on 4DCT scans. Materials and methods. Software was developed to interface with Eclipse TPS to calculate dose distributions on moving targets. This software splits each VMAT arc into partial arcs synchronized with the 4DCT scan. Dose matrices calculated on each breathing phase are accumulated on a single reference phase using the DIR dose accumulation algorithm in MIM Maestro software. For treatments planned on a cylindrically symmetric phantom with the target moving parallel to the symmetry axis and perpendicular to the VMAT arc’s planes, dose distributions calculated with a moving X-ray source are equivalent to those calculated with a moving phantom. Using a moving source to evaluate dynamic deliveries does not rely on DIR dose accumulation and therefore provides a novel method for verifying DIR-based dose accumulation algorithms on 4DCT datasets. Both methodologies were used for calculating dose distributions on the 20% phase of a 4DCT of a QUASAR phantom fitted with a cylindrical cedar insert containing a 3 cm acrylic target. The insert was moved following a 14 BPM realistic breathing trace with total amplitudes of 2 cm and 1 cm. Planar dose distributions along the principal axis were compared using gamma analysis.
275
Results. Gamma analysis was performed using DD = 2%, Dx = 2 mm (10% Dmax threshold). The minimum passing rates were 99.1% and 99.2%, corresponding to the sagittal planes of the 2 cm and 1 cm amplitude movement. Conclusion. The methodology presented here provides an easy and reliable way of assessing the performance of 4DCT DIR dose accumulation. The tested DIR accumulation algorithm performed exceptionally well, considering the ill-posed registration problem. http://dx.doi.org/10.1016/j.ejmp.2016.07.606
CAN AUTOMATED ANALYSIS OF SEQUENTIAL RETINAL IMAGES OF PEOPLE ATTENDING DIABETIC RETINOPATHY SCREENING PREDICT FUTURE REFERRAL TO OPHTHALMOLOGY? Sam Philip a, Arfan Ahmed b, Gordon Prescott c, Roger Staff b, Peter Sharp d,*, Jiawei Xu b, John Olson a a
Grampian Diabetes Research Unit, Aberdeen, UK Aberdeen Biomedical Imaging Centre, University of Aberdeen, UK c Institute of Applied Health Sciences, University of Aberdeen, UK d Medical Physics, University of Aberdeen, UK ⇑ Corresponding author. b
Introduction. Providing systemic screening to a growing diabetes population is a challenge for most screening programmes. We have previously developed software for the automated detection of diabetic retinopathy which is now routinely used within the Scottish Diabetic Retinopathy Screening programme. Purpose. In this study we explored whether automated analysis of sequential retinal images of people attending screening can predict future referral to ophthalmology. Materials and methods. We developed software to automatically measure whether the same microaneurysm (MA), the main indicator of retinopathy, appeared in sequential images and whether new MAs appeared, how close the MAs were to the fovea, the number of MAs within each quadrant of the retina, and the presence of other indicators of retinopathy, namely exudates and haemorrhages. A retrospective cohort study was conducted using 12,754 subjects to assess whether these features predicted retinopathy development. Results. A number of the novel features were independently associated with retinopathy progression of retinal images. These were higher MA counts close to the fovea, higher MA turnover between screening episodes and higher probabilities of haemorrhages anywhere in the image and exudates close to the fovea. We developed a model to estimate the risk of progression over the next 15 months. The sensitivity, specificity, PPV and NPV were 83.6%, 79.5%, 8.5% and 99.5%, respectively. We also developed a model for the risk of progression over the next 5 years. Conclusion. Features of retinopathy derived from automated analysis of sequential photographs can help predict the risk of progression to retinopathy needing referral to ophthalmology. http://dx.doi.org/10.1016/j.ejmp.2016.07.607
DETAILED MEASUREMENTS OF EXPOSURE TO ELECTROMAGNETIC RADIATION OF THE POPULATION OF NEAPOLI-SYKIES AREA Charalampos Koulouris *, Christina Athanasopoulou, Stefania Chantzi, Nausika Servitzoglou, Anastasios Siountas Medical Physics Laboratory, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece ⇑ Corresponding author.
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Abstracts / Physica Medica 32 (2016) 274–283
Introduction. The exposure to electromagnetic fields is of great concern to the majority of population due the large expansion of the use of mobile phones and telecommunication antennas. Purpose. The purpose of this study was to measure the intensity of electromagnetic fields to the municipality of Neapoli-Sykies and perform detailed measurements at specific places of interest on two different times. Material and method. The study took place in 3 stages. a) A quick check of the whole area of the municipality. An isotropic aerial was put on a wooden tripod and fastened on the roof of a car. The aerial was connected to the spectrum analyser FSH4, R&S. Each measurement covering the range 30 MHz–3 GHz lasted two minutes while the car was still. The exact position was acquired using a GPS device. The resulting data and measurement values of 1.109 points were entered in a geographic information system. b) Detailed measurements. At a second stage we acquired analytical measurements of each of eight frequency regions at 150 specific points of interest, namely base station antennas, schools, playgrounds and sport facilities. c) Detailed measurements in a later time. The detailed measurements were repeated after six months and all were entered in the same geographic information system. Results. All measurements of the first stage, covering the frequency zone of 30 MHz–3 GHz, were well below the lowest limit of 21,7 V/m. The measurements of the second stage were also below the proposed limits of each region and they were no statistical differences between the two measurements for each point. Conclusion. The intensities of electromagnetic fields on the whole and on every specific region are below the national limits. http://dx.doi.org/10.1016/j.ejmp.2016.07.608
OCCUPATIONAL EXPOSURE TO ELECTROMAGNETIC FIELDS – THE SITUATION IN GREECE G. Gourzoulidis a,c,*, P. Tsaprouni b, N. Skamnakis b, C. Tzoumanika b, E. Karastergios b, A. Gialofas b, E. Kalampaliki b, A. Achtipis a, C. Kappas c, T.G. Maris d, E. Karabetsos b a
Hazardous Agents Department, OHS Directorate, Hellenic Ministry of Labor, Greece b Non-Ionizing Radiation Office, Greek Atomic Energy Commission, Greece c Medical Physics Lab, Medical School, University of Thessaly, Greece d Medical Physics Lab, Medical School, University of Crete, Greece ⇑ Corresponding author. Introduction. Electromagnetic Fields (EMF) cover the biggest part of the non-ionizing spectrum (0–300 GHz) and affect not only the general public but mainly the workers. The legislative gap of occupational EMF exposure is covered by the Directive 2013/35/EU. Purpose. The three years period allowed for the implementation of the Directive into national law (1.7.2016), was used by the Hellenic Ministry of Labor, in conjunction with the Non-Ionizing Radiation Office of the Greek Atomic Energy Commission, to assess and measure the occupational EMF exposure in selected workplaces where EMF levels may reach high values.
Materials and methods. EMF measurements in the whole spectrum covered by the Directive were performed in certain installations of the Public Power Corporation S.A., the National Railway Organization, the Piraeus Port Authority S.A., the Hellenic Radio Television, in industrial sites and in hospitals with Magnetic Resonance Imaging systems. Results. Very few measurements exceed the Action Levels set by the Directive but the vast majority of them don’t even exceed the limits for the exposure of the general public. Overexposures are detected locally and are manageable through technical and organizational actions based on the principles for Occupational Health and Safety (OHS). Conclusion. A national occupational EMF exposure database is created that forms the basis not only for the EMF exposure assessment but also for the OHS management in total. Disclosure. Authors disclose that they don’t have any relationship that may bias their presentation. http://dx.doi.org/10.1016/j.ejmp.2016.07.609
DIGITAL BREAST TOMOSYNTHESIS: DOSE AND IMAGE QUALITY CHARACTERIZATION K. Fezzani a, J. Sage a,*, I. Fitton b, L. Hadid c, A. Moussier d, N. Pierrat e, A. Martineau f, C. Etard a a
IRSN, Fontenay-Aux-Roses, France Hôpital Européen Georges Pompidou, Paris, France c Hôpital Jean Verdier, Bondy, France d Institut Gustave Roussy, Villejuif, France e Institut Curie, Paris, France f Hôpital Saint-Louis, Paris, France ⇑ Corresponding author. b
Introduction. Digital Breast Tomosynthesis (DBT) offers a gain in sensitivity and in specificity for detection of breast cancers compared to 2D mammography, due to tissues’ overlapping reduction. The introduction of this technique within the French breast cancer screening program is being considered by the authorities in the coming years. Purpose. The aim of the study is to compare different DBT systems in term of dose and image quality. The evaluation of different image quality phantoms could lead to recommendations for incoming French regulatory internal quality control. Materials and methods. Five French hospitals with three different tomosynthesis systems and seven specific phantoms have been included in the study. Average Glandular Dose and SDNR are assessed for different thicknesses of PMMA. Regarding image quality, reconstructed images are analyzed on global score, spatial resolution, geometrical distortion and homogeneity aspects. Results. Preliminary results on dose and image quality for different models and modes are expected in May 2016 and will be discussed, as well as image quality and phantoms’ sensibility at different dose levels. Conclusion. The diversity in design of Digital Breast Tomosynthesis systems leads to an expected variability in terms of image quality and dose with breast thickness. Particular attention should be paid to the increase of the dose. Work at a national level on the regulatory quality control of tomosynthesis systems should be initiated as soon as possible in France. Disclosure. FITTON I: co-inventor of TomomamÒ phantom. http://dx.doi.org/10.1016/j.ejmp.2016.07.610
Purpose. Our goal was to validate this guideline and to investigate whether we could advise for or against some specific recommendations. Materials and methods. Between 2009 and 2016, 56 patients with CIEDs were treated in our institution. Dose to the CIED was assessed for every patient who was classified according to his risk. Patients were evaluated before, during and after radiotherapy by a cardiologist following guideline recommendations. Results. Our patient focus group consisted of 39, 15 and 1 patients categorized into low, medium and high risk groups, respectively. The median age was 75 (range 54–98) years. Most treatments were prostate primaries (20%), brain metastasis (16%), head and neck primaries (9%) lung primaries (7%), and esophagus (5%). The prescribed dose ranged from 8 to 78 Gy with a daily dose ranging from 1.8 to 8 Gy. The maximum doses to the CIEDs were 179.1 cGy, 751 cGy and 1270 cGy, for the low, medium and high risk groups, respectively. Radiation therapy was safely delivered in all patients. Conclusion. Our data support the fact that radiation dose seems to play a lesser role in inducing CIEDs malfunctions. Beam energy appears to be the essential factor in inducing these damaging effects according to the literature. Based on our work the following suggestions could be advocated: inactivation of antitachycardia therapies during RT as well as heart rhythm monitoring seems to be redundant and photon beam energy should be limited to 610 MV. http://dx.doi.org/10.1016/j.ejmp.2016.07.605
A METHOD FOR ASSESSING THE DOSIMETRIC CONSISTENCY OF SINGLE PHASE 4DCT DOSE ACCUMULATION BASED ON DEFORMING IMAGE REGISTRATION Flavio Enrico Nelli, Jeffrey Roy Harwood * Andrew Love Cancer Centre, University Hospital Geelong, Geelong, VIC, Australia ⇑ Corresponding author. Introduction. The interplay effect in FFF-VMAT SBRT deliveries can produce clinically relevant discrepancies between planned and delivered doses to moving targets. To assess the impact of motion on treatment delivery, dose distributions calculated on each phase of a 4DCT scan can be accumulated in a single phase using deforming image registration (DIR). The use of this technique as a treatment quality assurance tool requires dosimetric validation. Purpose. To develop a method for assessing the accuracy of DIRbased dose accumulation on 4DCT scans. Materials and methods. Software was developed to interface with Eclipse TPS to calculate dose distributions on moving targets. This software splits each VMAT arc into partial arcs synchronized with the 4DCT scan. Dose matrices calculated on each breathing phase are accumulated on a single reference phase using the DIR dose accumulation algorithm in MIM Maestro software. For treatments planned on a cylindrically symmetric phantom with the target moving parallel to the symmetry axis and perpendicular to the VMAT arc’s planes, dose distributions calculated with a moving X-ray source are equivalent to those calculated with a moving phantom. Using a moving source to evaluate dynamic deliveries does not rely on DIR dose accumulation and therefore provides a novel method for verifying DIR-based dose accumulation algorithms on 4DCT datasets. Both methodologies were used for calculating dose distributions on the 20% phase of a 4DCT of a QUASAR phantom fitted with a cylindrical cedar insert containing a 3 cm acrylic target. The insert was moved following a 14 BPM realistic breathing trace with total amplitudes of 2 cm and 1 cm. Planar dose distributions along the principal axis were compared using gamma analysis.
275
Results. Gamma analysis was performed using DD = 2%, Dx = 2 mm (10% Dmax threshold). The minimum passing rates were 99.1% and 99.2%, corresponding to the sagittal planes of the 2 cm and 1 cm amplitude movement. Conclusion. The methodology presented here provides an easy and reliable way of assessing the performance of 4DCT DIR dose accumulation. The tested DIR accumulation algorithm performed exceptionally well, considering the ill-posed registration problem. http://dx.doi.org/10.1016/j.ejmp.2016.07.606
CAN AUTOMATED ANALYSIS OF SEQUENTIAL RETINAL IMAGES OF PEOPLE ATTENDING DIABETIC RETINOPATHY SCREENING PREDICT FUTURE REFERRAL TO OPHTHALMOLOGY? Sam Philip a, Arfan Ahmed b, Gordon Prescott c, Roger Staff b, Peter Sharp d,*, Jiawei Xu b, John Olson a a
Grampian Diabetes Research Unit, Aberdeen, UK Aberdeen Biomedical Imaging Centre, University of Aberdeen, UK c Institute of Applied Health Sciences, University of Aberdeen, UK d Medical Physics, University of Aberdeen, UK ⇑ Corresponding author. b
Introduction. Providing systemic screening to a growing diabetes population is a challenge for most screening programmes. We have previously developed software for the automated detection of diabetic retinopathy which is now routinely used within the Scottish Diabetic Retinopathy Screening programme. Purpose. In this study we explored whether automated analysis of sequential retinal images of people attending screening can predict future referral to ophthalmology. Materials and methods. We developed software to automatically measure whether the same microaneurysm (MA), the main indicator of retinopathy, appeared in sequential images and whether new MAs appeared, how close the MAs were to the fovea, the number of MAs within each quadrant of the retina, and the presence of other indicators of retinopathy, namely exudates and haemorrhages. A retrospective cohort study was conducted using 12,754 subjects to assess whether these features predicted retinopathy development. Results. A number of the novel features were independently associated with retinopathy progression of retinal images. These were higher MA counts close to the fovea, higher MA turnover between screening episodes and higher probabilities of haemorrhages anywhere in the image and exudates close to the fovea. We developed a model to estimate the risk of progression over the next 15 months. The sensitivity, specificity, PPV and NPV were 83.6%, 79.5%, 8.5% and 99.5%, respectively. We also developed a model for the risk of progression over the next 5 years. Conclusion. Features of retinopathy derived from automated analysis of sequential photographs can help predict the risk of progression to retinopathy needing referral to ophthalmology. http://dx.doi.org/10.1016/j.ejmp.2016.07.607
DETAILED MEASUREMENTS OF EXPOSURE TO ELECTROMAGNETIC RADIATION OF THE POPULATION OF NEAPOLI-SYKIES AREA Charalampos Koulouris *, Christina Athanasopoulou, Stefania Chantzi, Nausika Servitzoglou, Anastasios Siountas Medical Physics Laboratory, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece ⇑ Corresponding author.
276
Abstracts / Physica Medica 32 (2016) 274–283
Introduction. The exposure to electromagnetic fields is of great concern to the majority of population due the large expansion of the use of mobile phones and telecommunication antennas. Purpose. The purpose of this study was to measure the intensity of electromagnetic fields to the municipality of Neapoli-Sykies and perform detailed measurements at specific places of interest on two different times. Material and method. The study took place in 3 stages. a) A quick check of the whole area of the municipality. An isotropic aerial was put on a wooden tripod and fastened on the roof of a car. The aerial was connected to the spectrum analyser FSH4, R&S. Each measurement covering the range 30 MHz–3 GHz lasted two minutes while the car was still. The exact position was acquired using a GPS device. The resulting data and measurement values of 1.109 points were entered in a geographic information system. b) Detailed measurements. At a second stage we acquired analytical measurements of each of eight frequency regions at 150 specific points of interest, namely base station antennas, schools, playgrounds and sport facilities. c) Detailed measurements in a later time. The detailed measurements were repeated after six months and all were entered in the same geographic information system. Results. All measurements of the first stage, covering the frequency zone of 30 MHz–3 GHz, were well below the lowest limit of 21,7 V/m. The measurements of the second stage were also below the proposed limits of each region and they were no statistical differences between the two measurements for each point. Conclusion. The intensities of electromagnetic fields on the whole and on every specific region are below the national limits. http://dx.doi.org/10.1016/j.ejmp.2016.07.608
OCCUPATIONAL EXPOSURE TO ELECTROMAGNETIC FIELDS – THE SITUATION IN GREECE G. Gourzoulidis a,c,*, P. Tsaprouni b, N. Skamnakis b, C. Tzoumanika b, E. Karastergios b, A. Gialofas b, E. Kalampaliki b, A. Achtipis a, C. Kappas c, T.G. Maris d, E. Karabetsos b a
Hazardous Agents Department, OHS Directorate, Hellenic Ministry of Labor, Greece b Non-Ionizing Radiation Office, Greek Atomic Energy Commission, Greece c Medical Physics Lab, Medical School, University of Thessaly, Greece d Medical Physics Lab, Medical School, University of Crete, Greece ⇑ Corresponding author. Introduction. Electromagnetic Fields (EMF) cover the biggest part of the non-ionizing spectrum (0–300 GHz) and affect not only the general public but mainly the workers. The legislative gap of occupational EMF exposure is covered by the Directive 2013/35/EU. Purpose. The three years period allowed for the implementation of the Directive into national law (1.7.2016), was used by the Hellenic Ministry of Labor, in conjunction with the Non-Ionizing Radiation Office of the Greek Atomic Energy Commission, to assess and measure the occupational EMF exposure in selected workplaces where EMF levels may reach high values.
Materials and methods. EMF measurements in the whole spectrum covered by the Directive were performed in certain installations of the Public Power Corporation S.A., the National Railway Organization, the Piraeus Port Authority S.A., the Hellenic Radio Television, in industrial sites and in hospitals with Magnetic Resonance Imaging systems. Results. Very few measurements exceed the Action Levels set by the Directive but the vast majority of them don’t even exceed the limits for the exposure of the general public. Overexposures are detected locally and are manageable through technical and organizational actions based on the principles for Occupational Health and Safety (OHS). Conclusion. A national occupational EMF exposure database is created that forms the basis not only for the EMF exposure assessment but also for the OHS management in total. Disclosure. Authors disclose that they don’t have any relationship that may bias their presentation. http://dx.doi.org/10.1016/j.ejmp.2016.07.609
DIGITAL BREAST TOMOSYNTHESIS: DOSE AND IMAGE QUALITY CHARACTERIZATION K. Fezzani a, J. Sage a,*, I. Fitton b, L. Hadid c, A. Moussier d, N. Pierrat e, A. Martineau f, C. Etard a a
IRSN, Fontenay-Aux-Roses, France Hôpital Européen Georges Pompidou, Paris, France c Hôpital Jean Verdier, Bondy, France d Institut Gustave Roussy, Villejuif, France e Institut Curie, Paris, France f Hôpital Saint-Louis, Paris, France ⇑ Corresponding author. b
Introduction. Digital Breast Tomosynthesis (DBT) offers a gain in sensitivity and in specificity for detection of breast cancers compared to 2D mammography, due to tissues’ overlapping reduction. The introduction of this technique within the French breast cancer screening program is being considered by the authorities in the coming years. Purpose. The aim of the study is to compare different DBT systems in term of dose and image quality. The evaluation of different image quality phantoms could lead to recommendations for incoming French regulatory internal quality control. Materials and methods. Five French hospitals with three different tomosynthesis systems and seven specific phantoms have been included in the study. Average Glandular Dose and SDNR are assessed for different thicknesses of PMMA. Regarding image quality, reconstructed images are analyzed on global score, spatial resolution, geometrical distortion and homogeneity aspects. Results. Preliminary results on dose and image quality for different models and modes are expected in May 2016 and will be discussed, as well as image quality and phantoms’ sensibility at different dose levels. Conclusion. The diversity in design of Digital Breast Tomosynthesis systems leads to an expected variability in terms of image quality and dose with breast thickness. Particular attention should be paid to the increase of the dose. Work at a national level on the regulatory quality control of tomosynthesis systems should be initiated as soon as possible in France. Disclosure. FITTON I: co-inventor of TomomamÒ phantom. http://dx.doi.org/10.1016/j.ejmp.2016.07.610