Radiation Dose from CT-Scan of Childhood’s Head: Results of the First Ivorian Survey in a Single Study Site

Objectives: This study aims to evaluate the level of X-ray doses used in childhood’s head as Local Diagnostic Reference Levels (LDRLs) in computed tomography (CT) at a university hospital in Côte d’Ivoire. The Diagnostic Reference Level (DRL) have been set up and used to prevent unusually high radiation doses used in radiology departments and is therefore an optimization tool for practices and procedures in medical X-ray imaging for the radiation protection of patients. Methods: A prospective study of volume CT dose index (CTDIvol) and dose length product (DLP) was performed on images of childhood’s head obtained from a CT-scanner of 64 bars equipped with the tube current modulation capability and manufactured by Hitachi Medical System. 122 CT-scan data from 55 childhood’s head were analyzed. The scan data were stratified in four age groups: Results: The 75th percentile of CTDIvol and DLP (set as LDRL) obtained with respect to the stratified age groups are: 22.5 mGy and 452.5 mGy∙cm, 27.7 mGy and 690.6 mGy∙cm, 28 mGy and 722.4 mGy∙cm, 33.6 mGy and 736.8 mGy∙cm respectively. These outcome values increase with respect to the age of pediatric patients and are comparable to DRLs values obtained internationally. Conclusions: Obtaining good image quality while using low dose in children’s head computed tomography for radiation protection require to setup more surveys in Côte d’Ivoire for regional and national DRL. We proposed through this survey LDRLs in terms of CTDIvol and DLP, comparable to international DRLs values. This survey will be strengthened by additional surveys in order to obtain national DRLs for the radiation protection of the child patient in Côte d’Ivoire.

Knowledge of radiation exposure associated with common trauma imaging modalities among orthopaedic surgeons,emergency medicine physicians,and general surgeons in the United States

BACKGROUND:Few contemporary studies have assessed physicians’knowledge of radiation exposure associated with common imaging studies,especially in trauma care.The purpose of this study was to assess the knowledge of physicians involved in caring for trauma patients regarding the effective radiation doses of musculoskeletal(MSK)imaging studies routinely utilized in the trauma setting.METHODS:An electronic survey was distributed to United States orthopaedic surgery,general surgery,and emergency medicine(EM)residency programs.Participants were asked to estimate the radiation dose for common imaging modalities of the pelvis,lumbar spine,and lower extremity,in terms of chest X-ray(CXR)equivalents.Physician estimates were compared to the true effective radiation doses.Additionally,participants were asked to report the frequency of discussing radiation risk with patients.RESULTS:A total of 218 physicians completed the survey;102(46.8%)were EM physicians,88(40.4%)wereorthopaedicsurgeons,and28(12.8%)weregeneralsurgeons.Physicians underestimated the effective radiation doses of nearly all imaging modalities,most notably for pelvic computed tomaography(CT)(median 50 CXR estimation vs.162 CXR actual)and lumbar CT(median 50 CXR estimation vs.638 CXR actual).There was no difference between physician specialties regarding estimation accuracy(P=0.133).Physicians who regularly discussed radiation risks with patients more accurately estimated radiation exposure(P=0.007).CONCLUSION:The knowledge among orthopaedic and general surgeons and EM physicians regarding the radiation exposure associated with common MSK trauma imaging is lacking.Further investigation with larger scale studies is warranted,and additional education in this area may improve care.

Conformity Assessment of Lead Aprons Used in Conventional Radiology: A Multi-Centre Survey in Togo

Aim: Lead aprons are used to protect against scattered radiation from the patient during interventional procedures and certain special conventional radiological examinations. Given the importance of the role lead aprons are supposed to play in radiation protection, we propose to assess their conformity in medical imaging departments in public and religious hospitals in Togo. Materials and method: A multi-centre survey conducted from 26 November to 06 December 2021 in the radiology departments of public and religious health facilities in Togo. All aprons in use were included. The evaluation criteria were physical (visual), quantitative (radiographic) and qualitative (dosimetric). Results: We had registred 43 aprons among wich 27 (62.79%) leaded aprons were labelled non-compliant and 16 (37.21%) were labelled compliant. Of the aprons judged to be non-compliant, 70.37% were more than 10 years old and 96.30% showed defects on the radiographic images. The most common defects were vampire marks (18.64%), multiple folds (16.96%), cracks (16.96%), multiple cracks (15.25%), tears (8.47%), absence of lead (5.08%), holes (3.39%) and lead corrosion (1.69%). Defective aprons (62.96%) had at least two defects. The defects were of thoraco-abdomino-pelvic (74.07%), thoracic (14.82%) and abdomino-pelvic (11.11%) topography. For indirect exposure at 50 and 70 kilovolts, all the aprons had an attenuation factor greater than 90%. After dosimetric measurement, 13.95% of aprons had attenuation factors below 90% for indirect exposure at 100 kilovolts. Conclusion: The compliance of the leaded decks is trifactorial (physical, radiographic and dosimetric). However, there is no significant difference in X-ray attenuation capacity between defective and normal decks.

Secondary and activated X(γ)radiation of SPHIC particle therapy facility

We report the secondary X(γ)radiation from the accelerator in a normal operating state and activated X(γ)radiation from the accelerator devices when the accelerator stops operating in the cancer treatment facility of the Shanghai Proton and Heavy Ion Center(SPHIC).These radiation measurements show us the structural radiation distribution along the beam lines and devices inside the accelerator room when the beam is on and off and can support the radiation protection design of the accelerator facility used for cancer treatment and help evaluate the accumulated radiation dose in the case of an emergency,such as a personal safety system failure or a radiation accident.The radiation dose rate measured in this facility shows that the facility is safe from the radiation protection point.After shooting the quality assurance(QA)beam,the radiation dose rate in the treatment room was also measured to investigate the radiation dose space distribution and decay time dependence.In addition,the time period before safely entering the treatment room after determining the shooting of the QA beam is recommended to be approximately 5 min.

Laser Device for the Protection of Biological Objects from the Damaging Action of Ionizing Radiation

Laser irradiation device for the protection of biological objects from the action of ionizing radiation to be used in practice has been manufactured （invention patent RU 2 428 228 C2）. Research of the action of y-radiation itself as well as of the combined action of laser devices on survival, weight, skin and the general mitotic index of the bone marrow cells （mitotic index of all nucleus-containing cells of the bone marrow） of C57BL/6 experimental young mice was carried out. The mice were irradiated with ionizing （whole body irradiation） and laser radiation, separately one by one in a special frame device. Laser radiation in the dose 1 mJ/cm^2 irradiated only the back of a mouse, or both the back and the abdomen of mice. In case of combined irradiation of mice, the time interval between two types of irradiation did not exceed 30 min. First, the mice were exposed to y-radiation then to laser radiation. The method of the laser radiation-protection of biological subjects contributes to an increase in the viability of mice, prevents the damages of skin and also increases the mitotic activity of mice bone marrow cells.

Application of microdosimetry on biological physics for ionizing radiation

Stochastic characterization of radiation interaction is of importance to cell damage. Microdosimetry is to investi- gate the random structures of particle tracks in order to understand the dose-effect in cellular scales. In the review, we introduced the basic concepts of microdosimetry as well as the experimental methods （TEPC） and Monte Carlo simula- tions. Three basic biophysical models are interpreted and compared, including the target model, linear-quadratic model, and microdosimetric-kinetic model. The bottlenecks in the current microdosimetry research are also discussed, which need the interdisciplinary contributions from biology, physics, mathematics, computer science and electric engineering.

Radiation Protection of a Patient Undergoing an Orthopedic Procedure by Using a Mobile C-Arm X-Ray System

Modern medicine is unthinkable without X-rays. Accurate diagnosis, leading to effective treatment, is largely based on precise X-ray examinations. The creation of new, modern equipment and various medical procedures that meet the increased requirements are a priority in our time. X-ray examinations are of particular importance for the orthopedic and traumatological clinics, where they provide information about presence of a fracture in the patient’s body, about the concrete operation performed or about the effect of a suitable treatment. Along with their benefits X-rays have also a harmful effect. This requires special care to protect from this radiation. In this direction, research is constantly being done to improve the quality of radiation protection. Park MR, Lee KM and co-authors, compare the dose load obtained using C-arm and O-arm X-ray systems (which have the capability of combined 2D fluoroscopy and 3D computed tomography imaging). In their study, an orthopedic surgical procedure using C-arm and O-arm systems in 2D fluoroscopy modes was simulated. The radiation doses to susceptible organs of the operators were investigated. He results obtained show that the O-arm system delivered higher doses to the sensitive organs of the operator in all configurations [1]. The article of Stephen Balte briefly reviews the available technologies for measuring or estimation of patient skin dose in the interventional fluoroscopic environment, created by various X-ray equipment including C-arm systems. Given that many patients require multiple procedures, this documentation also aids in the planning of follow up visits [2]. Chong Hing Wong, Yoshihisa Kotani and co-authors evaluate the radiation exposures (RE) to the patient and surgeon during minimally invasive lumbar spine surgery with instrumentation using C-arm image intensifier or O-arm intraoperative CT. The results they get are in favor of the O-arm system [3]. The article “Virtual fluoroscopy for intraoperative C-arm positioning and radiation dose reduction” discusses positioning of an intraoperative C-arm system to achieve clear visualization of a particular anatomical feature by a system for virtual fluoroscopy (called FluoroSim) that could dramatically reduce time and received dose during the procedures. FluoroSim was found to reduce the radiation exposure required for C-arm positioning without reducing positioning time or accuracy, providing a potentially valuable tool to assist surgeons [4]. In our study, we performed practical measurements to show how the patient can be treated by applying most effective radiation protection when using a mobile C-arm X-ray system. For the study, we used exposure upon a phantom placed on the patient’s table. For an X-ray shielding, we used a protective apron with a lead equivalent of 1 mm, placed in two layers on the phantom. In each subsequent series of exposures, the protective apron was placed on the phantom, in a different position relative to the X-ray beam. The general conclusion of our study is that in order to obtain maximum protection from scattered radiation when using C-arm X-ray systems, the patient must be protected by a shielding with a suitable lead equivalent for the procedure performed which must be placed between patient’s body and X-ray tube, perpendicular to the X-ray beam pointed toward the region of interest.

Reduction of Radiation Damage in Mice after Acute and Prolonged Irradiation with Gamma Rays by Means of Laser Device

An opportunity to use laser radiation as a means to reduce negative aftermath of acute and prolonged exposure to ionizing radiation was checked. The mice were exposed to γ- rays of ^60Co （whole body irradiation） in the dose of 7 Gy （the transitional clinical form of the acute radiation sickness）. The dose rate at acute irradiation was 1.14 Gy/min, and at prolonged exposure, 0.027 Gy/min. Laser radiation in the dose l mJ/cm^2 was used to irradiate only the back of a mouse. First, the mice were exposed to γ-radiation, then to laser radiation. The time interval between two types of irradiation did not exceed 30 min. It was shown that the radiation protection of mice with laser radiation is possible at exposure to ionizing radiation in a wide dose interval and can reduce negative after-effects of both the acute and prolonged radiation exposure.

ICRPANDCHINESERADIATIONPROTECTIONCOMMUNITY

１ＩｎｔｒｏｄｕｃｔｉｏｎＩｎｔｅｒｎａｔｉｏｎａｌＣｏｍｍｉｓｉｏｎｏｎＲａｄｉａｔｉｏｎＰｒｏｔｅｃｔｉｏｎ（ＩＣＲＰ）ｗａｓｅｓｔａｂｌｉｓｈｅｄｉｎ１９２８ａｓｔｈｅＩｎｔｅｒｎａｔｉｏｎａｌＸｒａｙａｎｄＲａｄｉｕｍＰｒｏｔｅｃｔｉｏｎＣ...

RADIATION HAZARD AND PROTECTION OF LOW ENERGY ACCELERATORS

In this paper, the origin and type of radiation hazards as well as the main aspects of radiation protection for low-energy accelerators are discussed in general, and the problems of radiation protection and the experimental results of the operational monitoring of the five accelerators in the institute of Nuclear Science and Technology,Sichuan University, namely, one 1.2 M cyclofron, two Cockroft-waltons and two Van de Graafts, as well as a powerful electron accelerator for industrial irradiation are described. The discussion and evaluation are made according to the requirments of the National standards GB 5172-85.

Knowledge and Practices of Health Professionals on the Optimization of Radiation Protection in Diagnostic Radiology in Children and Adults in the General Referral Hospitals of Bukavu in South Kivu, DRC

The aim of this research was to assess the knowledge and practices of radiological versus non-radiological health professionals on the optimisation of radiation protection in paediatric and adult radiology in BUKAVU hospitals. To achieve this, we surveyed a convenience sample of 73 health professionals including 23 radiologists working in the hospitals surveyed to assess knowledge and level of implementation of radiation protection principles. Also, physical parameters were taken for the calculation of entry doses in paediatric and adult radiology units for comparison with the International Commission on Radiological Protection (ICRP) diagnostic reference levels. After analysis of the data, the following was found: although radiologists have sufficient knowledge of radiation protection standards, technical constraints do not allow them to observe the dose limitation principle recommended by the ICRP. This is why several radiology departments, including those of the HPGRB, the MWANZI clinic and CIRIRI hospital, have proved to be very irradiating for children. However, radiologists and non-radiologists alike do not contribute positively to the optimisation of radiation protection in the diagnostic use of X-rays. Therefore, support in the implementation of radiation protection principles and regular monitoring of the units as well as replacement of non-standard equipment is necessary to promote patient and environmental safety by optimising radiation protection.

Capacity Building and Transfer of Know-how in Radiation Protection. Dissemination of Enetrap Projects Results

The ENETRAP （European Network on Education and Training in RAdiological Protection） project series, since the first edition in 2005 till the current ENETRAP III, always have been the objective to maintain a high level of competence in radiation protection （RP）, assuring the continued development of suitable well-trained personnel and adequate knowledge management. This objective is crucial to ensure future safe use of ionizing radiations （IR） and the development of new technologies in a safe way. A big effort and lot of work has been done in these 11 years including the new definitions in the BSS for RP Expert （RPE）, RP Officer （RPO） and Medical Physics Expert （MPE） which are the basis for future national development and implementation and adequate the high-level education and training （E＆T） in the countries. In order to manage all the valuable results of the projects and to distribute them to the society, is required a tool, developed with this specific propose, that will be the object of this paper.

The Gradient of γ-Rays Irradiation’s Energy and Its Use in Treatment of Cancer Diseases

The Ionising irradiations used mostly in the treatment of tumoral diseasses are: X, γ, β and e irradiations. The discussion will be about γ irradiations, produced in linear accelerator with photon energy 6 MV and 15 MV. It is important to know the absorption performance before and after the electronic equilibrium. This is a reason that we’ve used the function of dose gradient for irradiations γ. It represents the velocity of dose change as a function of depth in tissue. From skin to maximum dose value, the increase of G-function is more accentuated for γ-rays than for β-particles while after that the G-function decreasing is less sharp for γ-rays. Finally, we’ll discuss about the advantages in terms of radiation protection of γ-rays used in radiotherapy.

Study on Compliance with Radiation Protection Rules in the Medical Imaging Department of Pr Bocar Sidy Sall Hospital of Kati (Mali)

Objective: Evaluate the level of compliance with radiation protection rules in the medical imaging department of the University Hospital Center (CHU) of Kati. Methodology: This was a cross-sectional and descriptive study carried out in the medical imaging department of Pr Bocar Sidy Sall (BSS) Hospital of Kati. A questionnaire was developed and sent to the staff of the medical imaging department. The assessment focused on the radiation protection of personnel, radiation protection measures for patients, the delimitation and signage of zoning as well as the application of radiation protection principles. Results: Twenty-one people participated in the study, 90% of whom were men. The 30 - 39 age group was predominant with 61.90%. 33.33% of the staff knew the principles of radiation protection;86% of our sample knew the basic rules of radiation protection. The majority of the staff in the imaging department (61.90%) had a perfect knowledge of protective equipment. For 76% of our workforce, the limits of the radiation doses received are regulated in Mali. 76% of those surveyed have not taken any additional training in radiation protection. The doors are closed during the X-ray examination for 76.19% of the respondents and 95% of the staff put themselves behind the sealed screen during the examination. For 81% of the respondents, the design of the premises met radiation protection standards. 62% of practitioners have a dosimeter and 80% of them wear it during their shift. For 62% of our sample, the change of the dosimeter is quarterly. The systematic request for DDR (date of last menstrual period) in women and the adaptation of the delivered dose to the patient’s morphology was only carried out by 65% of practitioners. The majority of staff (81%) did not benefit from medical surveillance, while for 55% of respondents the level of radiation protection in the establishment was average. Conclusion: This study enabled us to highlight the shortcomings in terms of radiation protection within the imaging department of the CHU Kati.

Inventory of Radiation Protection in Hospitals of Level III in Senegal

The aim of this study was to evaluate the level of protection of employees who are exposed to radiation in a level III hospital establishment. It was a descriptive cross-sectional survey of six months’ duration, involving eight level III Hospitals (Aristide Le Dantec, Fann, Hoggy, Hear, Abass Ndao, Pikine, Touba, and Thiès) in Senegal. Sixty-one of the one hundred questionnaires were recovered (overall response rate of 61%). The population of the study was mainly female (54.1%). The average age was 38.57 with extremes ranging from 23 to 65 years old. In the places where ionizing radiation sources are handled, only at the Aristide Le Dantec Hospital did we find a “competent person in radiation protection”. This explained the lack of a classification of employees and work areas. Forty out of sixty-one (73.77%) had no knowledge of the basic principles of radiation protection (justification, optimisation, dose limitation) and had not ever taken radiation holidays. For radiovigilance, exposure time limits to ionizing radiation concerned only 29/61 or 47.54% of the study population. The inverse square law of distance was known by only 40 workers, of whom 15 had no compliance. We found the presence of dosifilms in only 7/61 or 11.47% of the workers. On the other hand, the use of lead aprons was well established and concerned 57/61 workers, i.e., 93.44%. In sum, ionizing radiation causes adverse health effects. The absence of a good radiation protection culture in Senegal requires the presence of at least 4 to 5 competent persons in radiation protection for quality training of workers in radiobiology, radiopathology and radiation protection.

The Role of Artificial Intelligence (AI) in Radiation Protection of Computed Tomography and Fluoroscopy: A Review

Background: The medical imaging world is currently changing with the introduction of advanced modalities to help with diagnosis. There is then the need for the application of Artificial Intelligence (AI) in areas such as radiation protection to improve the safety as far as radiations are concerned. This review article discusses the principles, some of the challenges of radiation protection and the possible role of Artificial Intelligence (AI) regarding radiation protection in computed tomography and fluoroscopy exams. Methods: A literature search was done using Google Scholar, Science Direct and Pubmed to search for relevant articles concerning the review topic. Results: Some of the challenges identified were outdated and old X-ray machines, lack of QA programs on the machines amongst others. It was discovered that AI could be applied in areas like scan planning and positioning, patient positioning amongst others in CT imaging to reduce radiation doses. With fluoroscopy, an AI enabled system helped in reducing radiation doses by selecting the region of interest of pathology and exposing that region. Conclusion: The application of AI will improve safety and standards of practice in medical imaging.

CT Scanning in Children in a Country with Limited Resources (Burkina Faso)

Objectives: To carry out the assessment of CT scans in children at the Charles de Gaulle University Hospital Center (CGUPH). Patients and Methods: This was a retrospective collection descriptive cross-sectional study conducted from July 1 to November 29, 2021 in the Radiology Department of the CGUPH, having included computed tomography (CT) reports of patients under 18 years of age. The variables explored were the data reported on CT reports (type of scan, reason for examination, dose delivered, and abnormalities described). Results: Two hundred and ninety explorations were collected. The average age was 2.93 years with extremes of 0 and 17 years. The sex ratio was 1.35. Computed tomography scans mainly explored the cranioencephalic, spinal and abdominal stages. The most common reasons for exploration were fetal suffering and head injuries. The most frequently described lesions were anoxo-ischemic sequelar lesions. Mean irradiation doses were 1096 ± 670 mGy·cm for the cranial-encephalic stage, 603 ± 332 mGy·cm for the spine and 311 ± 395 mGy·cm for the thoracic stage. Conclusion: CT in children mainly explored the brain and concerned children under 5 years. Anatomical irradiation doses were higher than diagnostic reference levels in several countries. Optimization of scanning protocols and availability of MRI would reduce ionizing radiation in children.