Dose level of pediatric CT scanning in a hospital / 中国辐射卫生

@#<b>Objective</b> To investigate the dose level of pediatric CT scan in one hospital, and to provide recommendations for optimized scanning. <b>Methods</b> The CT scan data of children were collected from this hospital to analyze the differences in typical dose values and typical scanning parameters between different age groups and different scanning parts. <b>Results</b> The sample size was >10 for routine cranial scan, routine maxillary sinus scan, and routine chest scan in each age group, and the 1-year-old group and the 5-year-old group had the same kV, mA, and CTDIvol values of routine cranial scan and maxillary sinus scan, but with relatively great differences in the parameters of chest scan. <b>Conclusion</b> Scanning parameters in this hospital can be further optimized, and optimization measures should be adopted continuously.

Assessment of knowledge and perceptions of medical radiation among caregivers and adolescent patients in the paediatric emergency department

INTRODUCTION@#This study aimed to assess understanding of the potential risks associated with medical imaging among caregivers and adolescent patients in a paediatric emergency department (PED) in Singapore.@*METHODS@#A prospective convenience sample survey was performed involving adolescents and caregivers presenting to our PED from December 2015 to May 2016. The questionnaire examined demographic data, knowledge of imaging procedures and radiation risks, and expectations regarding information provided about medical radiation.@*RESULTS@#A total of 349 questionnaires were returned (caregivers 82.5%, adolescents 17.5%). A mean of 6.2 ± 2.4 (out of 11) questions were correctly answered. Those who had tertiary education fared better than those who did not (36.4% vs. 17.2% scoring above the mean, p = 0.001). Age, gender, history of previous imaging and imaging performed during the visit did not affect the score. Two-thirds of the participants did not associate medical radiation with any negative lifetime risk of cancers or know that different scans entailed differing amounts of radiation. Most were unaware that the radiation dose in medical imaging is adjusted to a child's size. Among patients who underwent imaging, 90.1% received explanations on the need for scans, and 26.5% were informed of the risks involved. Almost all participants wished to be informed of imaging indications and risks. More preferred to learn this from physicians (75.6%) or technicians (51.6%) rather than through educational pamphlets (34.4%) or Internet resources (22.9%).@*CONCLUSION@#Awareness regarding medical radiation needs to be improved in our patient population. A mismatch exists between caregiver expectations and the actual procedure of disclosure of the risk associated with radiation.

Risk Assessment of Occupational Exposure of Workers Engaged in Radiation Practice without Monitoring Devices

Objective:This study was carried out to evaluate occupational dose of personnel, engaged in radiation work without wearing monitoring device, at five diagnostic centres in Abeokuta, OgunState metropolis, namely, Rainbow, New image, Bethel, Akinolugbade and Abiolad. Materials and Methods:Thermoluminescent dosimeters (TLDs) obtained from Radiation Protection Services, Lagos State University (LASU), Ojo were used for dose measurements. LASU is accredited by the Nigerian Nuclear Regulatory Authority (NNRA) to provide radiation monitoring services. The TLDs were distributed to each of the centre for personnel and area (control and supervised) monitoring. The period of exposure of the TLDs was three months. The exposed TLDs were returned to LASU for processing. The effective dose received by personnel per quarter was extrapolated to annual effective dose to make comparison with the International Commission on Radiation Protection (ICRP) recommended dose limit. The stochastic effect of the measured dose was also estimated. Results:Annual effective dose received by all personnel ranged from 1.16 -2.54 mSv. While the highest value was obtained by personnel at Bethel diagnostic centre, the lowest value was obtained at Akinolugbade. The risk of cancer associated with these values, estimated for a million population, was 112 and 61 at Bethel and Akinolugbade respectively. Conclusion:This study showed that the annual effective doses to personnelat these centres were below the ICRP recommended dose of 20 mSv per annum. However, the Managements of these diagnostic centres should provide monitoring devices for their radiation workers in line with NNRA authorization requirements

Current Status and Issues of Education on Radiation Health Risk Science / 医学教育

In accordance with the new model-core-curriculum for medical education, the current status of education about the science of radiation health was surveyed in all medical schools in Japan. Among the four learning points related to the “Biological effects of radiation and radiation hazards” , about half of the schools covered issues on “radiation and human body” and the “effect of medical radiation exposure” in one, or less than one, 60-minutes class, but did not touch on “radiation risk communication” and “radiological disaster medicine” . A significant deviation of human resources was also observed between schools. Learning tools such as presentation files and video content were preferred as education support materials. Therefore, development and distribution of the learning tools, especially in “radiation risk communication” and “radiological disaster medicine” , may be a first step to promoting high-quality education on the science of radiation health risk in each school’s curriculum.

Radiation Dose Reduction without Compromise to Image Quality by Alterations of Filtration and Focal Spot Size in Cerebral Angiography

OBJECTIVE: Different angiographic protocols may influence the radiation dose and image quality. In this study, we aimed to investigate the effects of filtration and focal spot size on radiation dose and image quality for diagnostic cerebral angiography using an in-vitro model and in-vivo patient groups. MATERIALS AND METHODS: Radiation dose and image quality were analyzed by varying the filtration and focal spot size on digital subtraction angiography exposure protocols (1, inherent filtration + large focus; 2, inherent + small; 3, copper + large; 4, copper + small). For the in-vitro analysis, a phantom was used for comparison of radiation dose. For the in-vivo analysis, bilateral paired injections, and patient cohort groups were compared for radiation dose and image quality. Image quality analysis was performed in terms of contrast, sharpness, noise, and overall quality. RESULTS: In the in-vitro analysis, the mean air kerma (AK) and dose area product (DAP)/frame were significantly lower with added copper filtration (protocols 3 and 4). In the in-vivo bilateral paired injections, AK and DAP/frame were significantly lower with filtration, without significant difference in image quality. The patient cohort groups with added filtration (protocols 3 and 4) showed significant reduction of total AK and DAP/patient without compromise to the image quality. Variations in focal spot size showed no significant differences in radiation dose and image quality. CONCLUSION: Addition of filtration for angiographic exposure studies can result in significant total radiation dose reduction without loss of image quality. Focal spot size does not influence radiation dose and image quality. The routine angiographic protocol should be judiciously investigated and implemented.

Standards and guidelines of radiation protection and safety in dental X-ray examinations / 中华口腔医学杂志

With the rapid development of imaging technology, the application of dental imaging in diagnosis, treatment planning, intraoperative surgical navigation, monitoring of treatment or lesion development and assessment of treatment outcomes is playing an essential role in oral healthcare. The increased total number of dental X-ray examinations is accompanied by a relatively significant increase in collective dose to patients as well as to dental healthcare workers, which is harmful to human bodies to a certain degree. Some radiation protection standards and guidelines in dental radiology have been published in European countries, US, Canada and Australia, etc. Adherence to these standards and guidelines helps to achieve images with diagnostic quality and avoid unnecessary and repeated exposures. However, no radiation protection standard or guideline with regard to dental X-ray examinations has been put in force so far in mainland China. Therefore, a literature review on available radiation protection standards and guidelines was conducted to provide reference to the development of radiation protection standards or guidelines in mainland China.

Radiology Residents' Awareness about Ionizing Radiation Doses in Imaging Studies and Their Cancer Risk during Radiological Examinations

OBJECTIVE: Imaging methods that use ionizing radiation have been more frequent in various medical fields with advances in imaging technology. The aim of our study was to make residents be aware of the radiation dose they are subjected to when they conduct radiological imaging methods, and of cancer risk. MATERIALS AND METHODS: A total of 364 residents participated in this descriptive study which was conducted during the period between October, 2008 and January, 2009. The questionnaires were completed under strict control on a one-to-one basis from each department. A chi2-test was used for the evaluation of data obtained. RESULTS: Only 7% of residents correctly answered to the question about the ionizing radiation dose of a posteroanterior (PA) chest X-ray. The question asking about the equivalent number of PA chest X-rays to the ionizing dose of a brain CT was answered correctly by 24% of residents; the same question regarding abdominal CT was answered correctly by 16% of residents, thorax CT by 16%, thyroid scintigraphy by 15%, intravenous pyelography by 9%, and lumbar spine radiography by 2%. The risk of developing a cancer throughout lifetime by a brain and abdominal CT were 33% and 28%, respectively. CONCLUSION: Radiologic residents should have updated knowledge about radiation dose content and attendant cancer risks of various radiological imaging methods during both basic medical training period and following practice period.

Percepción de la población respecto a los riesgos asociados a los estudios de imágenes / Public perception of radiation-related risks of imaging studies

Introduction: In recent years, diagnostic procedures using ionizing radiation have achieved a great boom, although patients are often unaware of the risks they involve. Objectives: To know how is ionizing radiation perceived by the population attending Clínica Dávila, Department of Radiology (DRCD).Methods: A voluntary and anonymous survey was conducted on patients and / or companions. Results: A total of 330 adults were surveyed. An 57 percent had completed higher education, whereas 7.9 percent had only finished elementary schooling; 78.8 percent had undergone three or more imaging tests. CT examination was considered to pose the highest levels of risk (42.4 percent), followed by Ultrasonography (30.6 percent). Discussion: The survey group was made up of young adults, mostly college graduates, and predominantly female. Surprinsingly enough, considering that obstetric sonography is commonly used during pregnancy, US was ranked second in terms of associated health risks. There is an evident interest in the subject, since 90 percent of responders would like to receive further information.

Introducción: Los procedimientos diagnósticos que usan radiación ionizante están en auge, aunque conllevan riesgos muchas veces desconocidos por los pacientes. Objetivos: Conocer la percepción de la población que acude al Departamento de Radiología de Clínica Dávila (DRCD) sobre la radiación. Material y métodos: Se aplicó una encuesta voluntaria y anónima a pacientes y/o acompañantes. Resultados: Se encuestó a 330 adultos. El 57 por ciento poseía estudios superiores y 7,9 por ciento sólo estudios básicos. El 78,8 por ciento se había efectuado 3 o más estudios radiológicos. La TC fue el examen considerado con mayor riesgo (42,4 por ciento), luego la US (30,6 por ciento). Discusión: El grupo encuestado fueron adultos jóvenes, con estudios superiores en su mayoría y con predominio femenino. Sorprendió que la US se considerara como el segundo examen de mayor riesgo, ya que las mujeres poseen mayor contacto con este estudio durante el embarazo. Hay interés en el tema, porque el 90 por ciento desea recibir información.