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An approach to vmat on radiation therapy treatments of pelvic and paraaortic lymph nodes
Abstracts / Physica Medica 32 (2016) 284–339
PATIENT DOSES IN A BIPLANE ANGIOGRAPHY SYSTEM C. Andres, M. Agulla, R. Torres, H. Perez-Garcia *, A. del Castillo, D. Miguel, J. de Frutos, D. Alonso, C. Perez, M. Gomez Hospital Clínico Universitario de Valladolid, Spain Corresponding author.
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Introduction. The development of biplane angiography systems is a huge advance in neurointerventional procedures but also a possible increase in patient doses. Purpose. This work aims to evaluate dosimetric parameters associated with doses to patients during the first year of use of a biplane angiography system Materials and methods. The angiography system analyzed was a Siemens Artist Zee biplane. Intervention’s parameters were obtained by means of the radiation dose structured report. 358 interventions were analyzed according to the following parameters: radiation time, skin dose, dose at interventional reference point and dosearea product (DAP). Average (±95% CI) and the maximum values of each data series were obtained Results. On average, each intervention needed 39:03 ±4:05 min of radiation time (71.2% due to plane A) with a maximum value of 7:12:34 h. DAP was, on average, 136 ±11 Gycm2 (80.8% due to plane A) with a maximum of 1435 Gycm2. Patient skin dose was, on average, 0.55 ± 0.07 Gy for plane A and 0.51 ± 0.09 Gy for plane B with maximum values of 4.24 Gy (plane A) and 4.20 Gy (plane B) Conclusion. Patient doses from a biplane angiography system are evaluated. Results show patient dose values significantly greater than those obtained in other interventional procedures. DAP and irradiation time were considerably higher for the plane A (usually craniocaudal). However, the skin dose for both planes shows similar values. Disclosure. The authors declare that they have no conflicts of interest. http://dx.doi.org/10.1016/j.ejmp.2016.07.165
AN APPROACH TO VMAT ON RADIATION THERAPY TREATMENTS OF PELVIC AND PARAAORTIC LYMPH NODES A. del Castillo a, D. Miguel a, H. Perez-Garcia a,*, M. Benito b, M. Sanchez-Belda a, D. Alonso a, J. de Frutos a, C. Andrés a, M. Agulla a, C. Pérez a, M. Gomez a, R. Torres a, F. Lopez-Lara a a
Hospital Clínico Universitario de Valladolid, Spain Hospital Provincial de Zamora, Spain ⇑ Corresponding author. b
Introduction. When large volumes need to be irradiated multiple organs at risk are involved. There is no doubt about the preeminence for conformal index and sparing of critical structures for VMAT, but an alternative regarding the use of single or multiple isocenter shows a subject for detailed analysis. Purpose. To compare VMAT in treatment of pelvic and paraaortic lymph nodes using single or double isocenter. Materials and Methods. A set of five patients are selected. For every patient an expert radiation oncologist contoured on CT images volumes and organs according to the RTOG guidelines. Plans were done in Eclipse 11 using Accuros XB algorithm for 6MV X-rays from a Clinac 2100-120MLC, using VMAT double full rotation arc with collimator rotation 30°-330°. For isocenter placement the Arc Geometric tool are used, for double isocenter only we allowed only longitudinal couch movement between isocenters. The same plan objectives are used for every single isocentre plan, but for organs at risk adjustments are made during optimization in order to get the best result for each case. When using double isocen-
307
tre the VMAT paraoortic plan is used as dose base for VMAT pelvic optimization. Results. Single isocenter shows higher irradiated volumes V5 are 1–2% and V20 up to 14%, sparing for liver and kidneys are improve for the double isocenter but with an average increase of 10% in monitor units each plan. Conclusion. Double isocenter plan improves organ sparing but worse PTV dose homogeneity. Disclosure. No conflicts of interest to declare. http://dx.doi.org/10.1016/j.ejmp.2016.07.166
OCCUPATIONAL RADIATION EXPOSURE DURING CERTAIN INTERVENTIONAL PROCEDURES A. Zailae b,*, A. Sulieman a a
King Saud Medical City (KSMC), Ministry of Health, Kingdom Riyadh, Saudi Arabia b Prince Sattam bin Abdulaziz University, College of Applied Medical Sciences, Radiology and Medical Imaging Department, Alkharj, Saudi Arabia ⇑ Corresponding author. Introduction. Interventional radiology procedures, which are minimally invasive procedures, have the potential to expose both patients and staff to a significant radiation doses. Purpose. The purposes of this study were to measure staff radiation dose during interventional cardiologic procedures before and after training program of radiation protection. Materials and methods. Staff were monitored using thermoluminescent dosimeter (TLD) chips for 118 procedures (27 procedures before the training program and the 91 procedures after the training program). Staff doses were monitored in 5 locations: forehead, thyroid, leg and chest. Results. The mean radiation dose for cardiologist were before the training program were 0.9 mGy for the forehead, 0.95 mGy for the thyroid, 1.42 mGy for the chest, 1.31 mGy and 1.44 mGy for the leg and for the hand and the total effective dose was 0.09 mSv while the mean radiation doses for assistant were 0.78 mGy for the chest, 0.91 mGy for the hand and the total effective dose was 0.06 mSv. Conclusions. A reduction of radiation dose for staff up to 45% was obtained after the training program. High patient and staff exposure is due to the lack of training and experience and protective tools. Interventional procedures remain operator dependent; therefore, continuous training is crucial. Disclosure. Authors have nothing to disclose. http://dx.doi.org/10.1016/j.ejmp.2016.07.167
ADVANCED MAGNETIC RESORANCE IMAGING AND THE CONTRIBUTION OF BRAIN SPECT IN THE DIFFERENTIAL DIAGNOSIS OF CEREBRAL TUMORS’ V. Tsitsia a,*, V. Valotasiou b, K. Fountas c, E. Kapsalaki d, I. Fezoulidis d, P. Georgoulias b, K. Theodorou a, I. Tsougos a a
Department of Medical Physics, University of Thessaly, Larisa, Greece Nuclear Medicine Department, University of Thessaly, Larisa, Greece c Neurosurgery Department, University of Thessaly, Larisa, Greece d Radiology Department, University of Thessaly, Larisa, Greece ⇑ Corresponding author. b
Purpose. The exciting new advances in MRI and Nuclear Medicine and the growing demands in Neuro-oncology make the need for diagnostic information combination evident. Under this perspective
PATIENT DOSES IN A BIPLANE ANGIOGRAPHY SYSTEM C. Andres, M. Agulla, R. Torres, H. Perez-Garcia *, A. del Castillo, D. Miguel, J. de Frutos, D. Alonso, C. Perez, M. Gomez Hospital Clínico Universitario de Valladolid, Spain Corresponding author.
⇑
Introduction. The development of biplane angiography systems is a huge advance in neurointerventional procedures but also a possible increase in patient doses. Purpose. This work aims to evaluate dosimetric parameters associated with doses to patients during the first year of use of a biplane angiography system Materials and methods. The angiography system analyzed was a Siemens Artist Zee biplane. Intervention’s parameters were obtained by means of the radiation dose structured report. 358 interventions were analyzed according to the following parameters: radiation time, skin dose, dose at interventional reference point and dosearea product (DAP). Average (±95% CI) and the maximum values of each data series were obtained Results. On average, each intervention needed 39:03 ±4:05 min of radiation time (71.2% due to plane A) with a maximum value of 7:12:34 h. DAP was, on average, 136 ±11 Gycm2 (80.8% due to plane A) with a maximum of 1435 Gycm2. Patient skin dose was, on average, 0.55 ± 0.07 Gy for plane A and 0.51 ± 0.09 Gy for plane B with maximum values of 4.24 Gy (plane A) and 4.20 Gy (plane B) Conclusion. Patient doses from a biplane angiography system are evaluated. Results show patient dose values significantly greater than those obtained in other interventional procedures. DAP and irradiation time were considerably higher for the plane A (usually craniocaudal). However, the skin dose for both planes shows similar values. Disclosure. The authors declare that they have no conflicts of interest. http://dx.doi.org/10.1016/j.ejmp.2016.07.165
AN APPROACH TO VMAT ON RADIATION THERAPY TREATMENTS OF PELVIC AND PARAAORTIC LYMPH NODES A. del Castillo a, D. Miguel a, H. Perez-Garcia a,*, M. Benito b, M. Sanchez-Belda a, D. Alonso a, J. de Frutos a, C. Andrés a, M. Agulla a, C. Pérez a, M. Gomez a, R. Torres a, F. Lopez-Lara a a
Hospital Clínico Universitario de Valladolid, Spain Hospital Provincial de Zamora, Spain ⇑ Corresponding author. b
Introduction. When large volumes need to be irradiated multiple organs at risk are involved. There is no doubt about the preeminence for conformal index and sparing of critical structures for VMAT, but an alternative regarding the use of single or multiple isocenter shows a subject for detailed analysis. Purpose. To compare VMAT in treatment of pelvic and paraaortic lymph nodes using single or double isocenter. Materials and Methods. A set of five patients are selected. For every patient an expert radiation oncologist contoured on CT images volumes and organs according to the RTOG guidelines. Plans were done in Eclipse 11 using Accuros XB algorithm for 6MV X-rays from a Clinac 2100-120MLC, using VMAT double full rotation arc with collimator rotation 30°-330°. For isocenter placement the Arc Geometric tool are used, for double isocenter only we allowed only longitudinal couch movement between isocenters. The same plan objectives are used for every single isocentre plan, but for organs at risk adjustments are made during optimization in order to get the best result for each case. When using double isocen-
307
tre the VMAT paraoortic plan is used as dose base for VMAT pelvic optimization. Results. Single isocenter shows higher irradiated volumes V5 are 1–2% and V20 up to 14%, sparing for liver and kidneys are improve for the double isocenter but with an average increase of 10% in monitor units each plan. Conclusion. Double isocenter plan improves organ sparing but worse PTV dose homogeneity. Disclosure. No conflicts of interest to declare. http://dx.doi.org/10.1016/j.ejmp.2016.07.166
OCCUPATIONAL RADIATION EXPOSURE DURING CERTAIN INTERVENTIONAL PROCEDURES A. Zailae b,*, A. Sulieman a a
King Saud Medical City (KSMC), Ministry of Health, Kingdom Riyadh, Saudi Arabia b Prince Sattam bin Abdulaziz University, College of Applied Medical Sciences, Radiology and Medical Imaging Department, Alkharj, Saudi Arabia ⇑ Corresponding author. Introduction. Interventional radiology procedures, which are minimally invasive procedures, have the potential to expose both patients and staff to a significant radiation doses. Purpose. The purposes of this study were to measure staff radiation dose during interventional cardiologic procedures before and after training program of radiation protection. Materials and methods. Staff were monitored using thermoluminescent dosimeter (TLD) chips for 118 procedures (27 procedures before the training program and the 91 procedures after the training program). Staff doses were monitored in 5 locations: forehead, thyroid, leg and chest. Results. The mean radiation dose for cardiologist were before the training program were 0.9 mGy for the forehead, 0.95 mGy for the thyroid, 1.42 mGy for the chest, 1.31 mGy and 1.44 mGy for the leg and for the hand and the total effective dose was 0.09 mSv while the mean radiation doses for assistant were 0.78 mGy for the chest, 0.91 mGy for the hand and the total effective dose was 0.06 mSv. Conclusions. A reduction of radiation dose for staff up to 45% was obtained after the training program. High patient and staff exposure is due to the lack of training and experience and protective tools. Interventional procedures remain operator dependent; therefore, continuous training is crucial. Disclosure. Authors have nothing to disclose. http://dx.doi.org/10.1016/j.ejmp.2016.07.167
ADVANCED MAGNETIC RESORANCE IMAGING AND THE CONTRIBUTION OF BRAIN SPECT IN THE DIFFERENTIAL DIAGNOSIS OF CEREBRAL TUMORS’ V. Tsitsia a,*, V. Valotasiou b, K. Fountas c, E. Kapsalaki d, I. Fezoulidis d, P. Georgoulias b, K. Theodorou a, I. Tsougos a a
Department of Medical Physics, University of Thessaly, Larisa, Greece Nuclear Medicine Department, University of Thessaly, Larisa, Greece c Neurosurgery Department, University of Thessaly, Larisa, Greece d Radiology Department, University of Thessaly, Larisa, Greece ⇑ Corresponding author. b
Purpose. The exciting new advances in MRI and Nuclear Medicine and the growing demands in Neuro-oncology make the need for diagnostic information combination evident. Under this perspective