As children are prone to be more radiosensitive than adults, it is imperative to assess the Entrance Skin Doses (ESDs) for patients being examined by X-rays, in order to ensure the optimization of dose while consideri...As children are prone to be more radiosensitive than adults, it is imperative to assess the Entrance Skin Doses (ESDs) for patients being examined by X-rays, in order to ensure the optimization of dose while considering a number of other fickles. The ESD received by 50 paediatrics (aged 1-13 years) undergoing 8 types of X-ray examinations were measured at Federal Teaching Hospital, Ido-Ekiti, Ekiti, Nigeria, within a period of February 2019 to March 2020 using thermoluminescent dosimeters. The mean ± SD of ESDs were 0.85 ± 0.32, 2.04 ± 0.75, 0.60 ± 0.07, 0.62 ± 0.22, 0.57 ± 0.24, 1.75 ± 0.76, 0.93 ± 0.31 and 0.63 ± 0.06 mGy for Chest, Skull, Hand, Forearm, Knee, Abdomen, Leg and Feet, respectively. The mean ESDs were found to be within the recommended reference dose in all examinations, except for the Chest examination which was higher. The data obtained in this study will serve as existing data in Nigeria for future research works, as it would assist in optimizing dose to patients, especially the paediatrics.展开更多
Objective: The current research study aims to calculate entrance surface air kerma for skull, chest, cervical spine, lumbar spine, and pelvic X-ray examinations in interior posterior and posterior interior positions a...Objective: The current research study aims to calculate entrance surface air kerma for skull, chest, cervical spine, lumbar spine, and pelvic X-ray examinations in interior posterior and posterior interior positions and generate a method for chest dose reduction to decrease radiation risk. Materials and Methods: The indirect dose measurement was used in the current research. The X-ray tube output was measured using RAD-CHECK Plus ionization chamber and the indirect entrance surface air kerma was calculated via applying physical acquisition parameters such as a focus on skin distance, tube current times exposure time (mAs), and applied tube voltage (kV), and applying a mathematical model. Results: The main findings were obtained from comparing the radiation doses with the reference levels of International organizations such as the American College of Radiology and the International Atomic Energy Authority. The mean entrance skin dose for the skull (AP), skull (PA), skull (LAT), cervical spine (PA), cervical spine (LAT), lumbar spine (AP), lumbar spine (LAT), pelvis (AP), and pelvis (LAT) of adult X-ray examinations was within the diagnostic reference dose level values obtained by ACR (2018) except for the ESD for chest (AP) which was 0.88 mGy. Conclusions: The results of the study concluded that by adjusting the applied tube voltage, kV, and tube current product time, mAs decreased the radiation dose to the chest X-ray by 58%.展开更多
The radiation dose received by patients undergoing chest radiography was included. 200 patients who attended these investigations in 10 hospitals in Iran were randomly selected from all ages groups and both female and...The radiation dose received by patients undergoing chest radiography was included. 200 patients who attended these investigations in 10 hospitals in Iran were randomly selected from all ages groups and both female and male. Critically ill patients were excluded. This paper presents the work, which was implemented on 200 patients and evaluated using the entrance skin dose （ESD） in the posterior anterior （PA） chest projection measured directly at the center of the X-ray field. In addition, the machine room, and dark room .parameters, as well as work practices and repeat rates were studied. The quality control （QC） parameters and the ESD before and after QC were evaluated utilizing an anthropomorphic phantom to define the optimal exposure condition at all hospitals. This research shows that after using the QC parameters and after optimization of the exposure conditions, the ESD was decreased by 42% on average. Also the qua/ity of the radiographs generally increased. The reported method is easily implemented in any clinical situation where optimization of chest radiography is needed.展开更多
The purpose of the present study is to evaluate the uncertainties of in vivo dosimetry measured with diode detectors for conformal radiation therapy techniques in order to define appropriate tolerance levels for pelvi...The purpose of the present study is to evaluate the uncertainties of in vivo dosimetry measured with diode detectors for conformal radiation therapy techniques in order to define appropriate tolerance levels for pelvis and breast treatment in MEIH （Middle East Institute of Health）. The present work is carried out on 30-472 and 30-473 diode detectors irradiated by 4 and 15MV photon beams of a medical linear accelerator Synergy from ELEKTA. Dose computation is performed with Pinnacle 7.4 k treatment planning system. First, an estimation of the uncertainties in a simple geometric case, using a water-equivalent solid phantom is done. Secondly, each treatment parameter such as field size, beam angle, beam modifiers and source-skin distance is evaluated in order to simulate the conformal radiation treatments used in the present institution for the main anatomical sites. Interpretation of entrance dose in-vivo measurements requires the determination of appropriate tolerance levels. Indeed, the authors found that the 5% action level proposed in the literature underestimates the uncertainties in the treatment process. A method for the evaluation of tolerance/action levels related to the different anatomical sites is developed. By the end of the present study the authors have developed an integrated monitoring system that offers accurate information about the dose received by patients.展开更多
Diagnostic Reference Levels (DRLs) are indicators that allow assessing the quality of equipment and procedures from the point of view of the doses delivered to patients and subsequently initiate corrective actions if ...Diagnostic Reference Levels (DRLs) are indicators that allow assessing the quality of equipment and procedures from the point of view of the doses delivered to patients and subsequently initiate corrective actions if necessary. The purpose of this study is to encourage health professionals to investigate patient radiation doses and to determine whether those doses comply with the principles of radiation protection in medical fields so as to improve practices by reducing patient exposure without reducing clinical effectiveness. To perform this work, we have investigated patient doses for different radiological examinations from six (6) medical centers in Dakar, including the following nine routine types: chest (PA), abdomen (AP), pelvis (AP), cervical spine (AP), lumbar spine (AP, Lat), hip (AP), thoracic spine (AP, Lat). Three types of data were collected, <em>i.e.</em>, X-ray tube machine data, patient data and output measurements. The data were analyzed statistically and the median, minimum, maximum, and third quartile values were calculated and displayed throughout boxplots graphs for all exams and medical centers. The two sigma range (95% confidence interval) was also checked. Comparison of third quartiles of Entrance Surface Dose (ESD) and Dose Area Product (DAP) by type of examination with recommended international DRLs was performed. The third quartile of ESD for pelvis (AP) and thoracic spine (AP) was up to 16% and 38% higher, respectively than their corresponding DRLs in the European Commission Report RP 180 Part 2. For all exams, except thoracic spine (lat), the third quartiles of the dose area product were higher than the corresponding DRLs in the above report. The source of dose variability between medical centers was related to many parameters such as poor radiographic techniques, lack of modern X-ray machines and adequately documented radiation protection practices. The results show the need to develop protocols for dose measurement as well as to carry out quality assurance programs and dose optimization in Senegal.展开更多
文摘As children are prone to be more radiosensitive than adults, it is imperative to assess the Entrance Skin Doses (ESDs) for patients being examined by X-rays, in order to ensure the optimization of dose while considering a number of other fickles. The ESD received by 50 paediatrics (aged 1-13 years) undergoing 8 types of X-ray examinations were measured at Federal Teaching Hospital, Ido-Ekiti, Ekiti, Nigeria, within a period of February 2019 to March 2020 using thermoluminescent dosimeters. The mean ± SD of ESDs were 0.85 ± 0.32, 2.04 ± 0.75, 0.60 ± 0.07, 0.62 ± 0.22, 0.57 ± 0.24, 1.75 ± 0.76, 0.93 ± 0.31 and 0.63 ± 0.06 mGy for Chest, Skull, Hand, Forearm, Knee, Abdomen, Leg and Feet, respectively. The mean ESDs were found to be within the recommended reference dose in all examinations, except for the Chest examination which was higher. The data obtained in this study will serve as existing data in Nigeria for future research works, as it would assist in optimizing dose to patients, especially the paediatrics.
文摘Objective: The current research study aims to calculate entrance surface air kerma for skull, chest, cervical spine, lumbar spine, and pelvic X-ray examinations in interior posterior and posterior interior positions and generate a method for chest dose reduction to decrease radiation risk. Materials and Methods: The indirect dose measurement was used in the current research. The X-ray tube output was measured using RAD-CHECK Plus ionization chamber and the indirect entrance surface air kerma was calculated via applying physical acquisition parameters such as a focus on skin distance, tube current times exposure time (mAs), and applied tube voltage (kV), and applying a mathematical model. Results: The main findings were obtained from comparing the radiation doses with the reference levels of International organizations such as the American College of Radiology and the International Atomic Energy Authority. The mean entrance skin dose for the skull (AP), skull (PA), skull (LAT), cervical spine (PA), cervical spine (LAT), lumbar spine (AP), lumbar spine (LAT), pelvis (AP), and pelvis (LAT) of adult X-ray examinations was within the diagnostic reference dose level values obtained by ACR (2018) except for the ESD for chest (AP) which was 0.88 mGy. Conclusions: The results of the study concluded that by adjusting the applied tube voltage, kV, and tube current product time, mAs decreased the radiation dose to the chest X-ray by 58%.
文摘The radiation dose received by patients undergoing chest radiography was included. 200 patients who attended these investigations in 10 hospitals in Iran were randomly selected from all ages groups and both female and male. Critically ill patients were excluded. This paper presents the work, which was implemented on 200 patients and evaluated using the entrance skin dose （ESD） in the posterior anterior （PA） chest projection measured directly at the center of the X-ray field. In addition, the machine room, and dark room .parameters, as well as work practices and repeat rates were studied. The quality control （QC） parameters and the ESD before and after QC were evaluated utilizing an anthropomorphic phantom to define the optimal exposure condition at all hospitals. This research shows that after using the QC parameters and after optimization of the exposure conditions, the ESD was decreased by 42% on average. Also the qua/ity of the radiographs generally increased. The reported method is easily implemented in any clinical situation where optimization of chest radiography is needed.
文摘The purpose of the present study is to evaluate the uncertainties of in vivo dosimetry measured with diode detectors for conformal radiation therapy techniques in order to define appropriate tolerance levels for pelvis and breast treatment in MEIH （Middle East Institute of Health）. The present work is carried out on 30-472 and 30-473 diode detectors irradiated by 4 and 15MV photon beams of a medical linear accelerator Synergy from ELEKTA. Dose computation is performed with Pinnacle 7.4 k treatment planning system. First, an estimation of the uncertainties in a simple geometric case, using a water-equivalent solid phantom is done. Secondly, each treatment parameter such as field size, beam angle, beam modifiers and source-skin distance is evaluated in order to simulate the conformal radiation treatments used in the present institution for the main anatomical sites. Interpretation of entrance dose in-vivo measurements requires the determination of appropriate tolerance levels. Indeed, the authors found that the 5% action level proposed in the literature underestimates the uncertainties in the treatment process. A method for the evaluation of tolerance/action levels related to the different anatomical sites is developed. By the end of the present study the authors have developed an integrated monitoring system that offers accurate information about the dose received by patients.
文摘Diagnostic Reference Levels (DRLs) are indicators that allow assessing the quality of equipment and procedures from the point of view of the doses delivered to patients and subsequently initiate corrective actions if necessary. The purpose of this study is to encourage health professionals to investigate patient radiation doses and to determine whether those doses comply with the principles of radiation protection in medical fields so as to improve practices by reducing patient exposure without reducing clinical effectiveness. To perform this work, we have investigated patient doses for different radiological examinations from six (6) medical centers in Dakar, including the following nine routine types: chest (PA), abdomen (AP), pelvis (AP), cervical spine (AP), lumbar spine (AP, Lat), hip (AP), thoracic spine (AP, Lat). Three types of data were collected, <em>i.e.</em>, X-ray tube machine data, patient data and output measurements. The data were analyzed statistically and the median, minimum, maximum, and third quartile values were calculated and displayed throughout boxplots graphs for all exams and medical centers. The two sigma range (95% confidence interval) was also checked. Comparison of third quartiles of Entrance Surface Dose (ESD) and Dose Area Product (DAP) by type of examination with recommended international DRLs was performed. The third quartile of ESD for pelvis (AP) and thoracic spine (AP) was up to 16% and 38% higher, respectively than their corresponding DRLs in the European Commission Report RP 180 Part 2. For all exams, except thoracic spine (lat), the third quartiles of the dose area product were higher than the corresponding DRLs in the above report. The source of dose variability between medical centers was related to many parameters such as poor radiographic techniques, lack of modern X-ray machines and adequately documented radiation protection practices. The results show the need to develop protocols for dose measurement as well as to carry out quality assurance programs and dose optimization in Senegal.
