Have to be justified and be as low as possible, respecting the national dose In keeping with the ALARA principle (as low as reasonably achievable), all exposures Other personal protective equipments (Decree-law 180/2002 Soares et al. To protect patients and healthcare professionals. Radiation exposure, special radiation protection measures have to be considered Since the rooms where mobile x-rays are performed aren’t prepared for These effects and to ensure the best working conditions for the professionals,ĭiagnostic reference levels were developed to standardise the doses applied by Stage of a set of phenomena that cause biological changes of two types: theĪcute or chronic effect and the immediate or late manifestations. Physical interactions of radiation with matter constitute the first May produce scattered radiation, which is prejudicial for image quality andĬontributes to patient and professional/staff exposure (Lima 2009). The interaction of radiation with tissues The transition between these two phenomena being approximately at 80 kVp in the However, the best known are the photoelectric and Compton effects, Several effects result from interaction of the radiation with the They rely on the differences in the coefficients of attenuation of human The radiograms are acquired using ionising radiation and It is also a useful tool to evaluate devices for clinical support, suchĪs catheters, tracheal tubes and other life support systems (American College Radiation for diagnostic and treatment purposes has increased due to theĭevelopment of new equipment and easier access to radiologic examinations. Protective measures and stand behind the mobile equipment. Therefore, exposed workers should use a personal dosimeter, employ Is not exceeded (12 mSv/year), but for members of the public it is exceeded (2 For distances above 1m, the national dose limits for exposed workers Tangential projection, using a full body anthropomorphic phantom and an x-rayĭetector. Reproducing the technical conditions for the chest anteroposterior (AP)Įxamination in supine and semi-supine positions as well as for the abdomen The reliability and validity of the simulation were examined.The main goal of this research was to quantify scatter radiationĮxposure from mobile x-ray examinations. At the same horizontal distance from the irradiation axis, it was observed that the air dose was relatively higher at the level of gonad region than at the eye level.Ĭonclusions: The proposed visualization approach illustrates a three dimensional dose simulation in local display density, which arouses the awareness about prolonged radiation exposure in clinical environment. ![]() A significant monotonic association between the MC simulation and physical measurement of dose values was identified ( r s=0.822 and P<.01). Results: At 19 representative locations taking into account the work area and radiosensitive organs of healthcare workers, the trend compliance of the simulated with the measured dose values was examined using the correlation analysis. EGSnrc-based DOSXYZnrc code was applied to simulate the scatter dose distribution and the physical measurement of radiation dose was performed using an ionization chamber radiation detector. In this study, a stack of tissue equivalent slabs were used as the object under fluoroscopic irradiation. However, the application and validation of MC simulation under fluoroscopy setting have not been found yet. MC simulation is a sophisticated statistical method, which has been widely applied for modeling scatter radiation in general X-ray examination room. ![]() As the spatial difference in dose is never negligible, the scatter radiation distribution under fluoroscopic exposures is thus worth investigating. Methods: In fluoroscopy and interventional radiology examinations, relatively high level of occupational dose is delivered to healthcare workers due to prolonged radiation exposure in imaging procedures. ![]() Objective: This study developed a three-dimensional visualization method for presenting the geometric pattern of the relative dose generated by Monte Carlo (MC) simulation and validated the simulated dose values against the physical measurement.
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