Background: In 2021, the Korean government proposed a new CT diagnostic reference level. This study performed a nationwide survey and developed new DRLs and AD for 13 common CT examinations. We compared other countries’ DRLs for CT examinations. Methods: This study investigated the CTDI_vol and DLP of the 12 types of CT protocols for adults and brain CT protocol for pediatrics. A total of 7829 CT examinations were performed using 225 scanners. We defined the DRLs values in the distribution of radiation exposure levels to determine the nationwide patient dose and distribution status of the dose. Results: This study showed that the new Korean national CT DRLs are slightly higher or similar to those of previous surveys and are similar or lower than those of other countries. In some protocols, although the DLP value increased, the CTDI_vol decreased; therefore, it can be concluded that the patient’s dose in CT examinations was well managed. Conclusions: The new CT DRLs were slightly higher than or similar to that of the previous survey and were evaluated to be similar or lower than CT DRLs of other countries. These DRLs will be used for radiation optimization and effective dose calculation for an individual.

In radiography, the exposure index (EI), as per the International Electrotechnical Commission standard, depends on the incident beam quality and exposure dose to the digital radiography system. Today automatic exposure control (AEC) systems are commonly employed to obtain the optimal image quality. An AEC system can maintain a constant incident exposure dose on the image receptor regardless of the patient thickness. In this study, we investigated the relationship between body thickness, entrance surface dose (ESD), EI, and the exposure indicator (S value) with the aim of using EI as the dose optimization tool in digital chest radiography (posterior–anterior and lateral projection). The exposure condition from the Korean national survey for determining diagnostic reference levels and two digital radiography systems (photostimulable phosphor plate and indirect flat panel detector) were used. As a result, ESD increased as the phantom became thicker with constant exposure indicator, which indicates similar settings to an AEC system, but the EI indicated comparatively constant values without following the tendency of ESD. Therefore, body thickness should be considered under the AEC system for introducing EI as the dose optimization tool in digital chest radiography.

Cardiac angiography to visualize the cardiac coronary artery for lesions causes a lot of radiation exposure dose to the interventional cardiologist. We evaluated the occupational radiation exposure to the interventional cardiologist based on changes to the angle of the X-ray tube used in cardiac angiography and calculated the conversion factor for effective dose in this study. To evaluate the occupational radiation exposure resulting from scattered radiation to interventional cardiologists, organ doses for eyeball, thyroid, and heart were calculated using Monte Carlo simulation with korean typical man(KTMAN) phantom at the left anterior oblique (LAO)30/cranial (CRAN)30, CRAN40, right anterior oblique (RAO)30/CRAN30, RAO30/caudal(CAUD)20, CAUD39, LAO40/CAUD35, and LAO40 positions in the femoral and the radial artery puncture. In this study, analysis of the different angles showed the highest radiation exposure on LAO30/CRAN30 and CRAN40 position, which were 150.65% and 135.3%, respectively, compared to AP angles. Therefore, to reduce occupational dose for interventional cardiologists, it is recommended that radiation protection, such as using radiation shield and personal protective equipment (PPE), be used at LAO30/CRAN30 and CRAN40 angulation, and the conversion factor for calculating the organ dose received by the interventional cardiologists based on patient dose can be applied for improved occupational dose management.

Intra-hospital transport is associated with fatal risks for the occupants of an intensive care unit (ICU). Thus, mobile CT is used in ICUs. In this study, two-dimensional equivalent dose distribution data were expanded using the inverse square law of distance to identify the potential exposure of radiologic technologists and public and the maximum number of possible daily CT procedures. The exposure dose at 1.5 m from the isocentre of the mobile CT was 2.260 μSv. Based on the dose limitation (5 mSv/yr for controlled area and 1 mSv/yr for uncontrolled area) as per National Council on Radiation Protection and Measurement report, the number of possible scans per day was 9 for radiologic technologists and 2 for public. When using the radiation shielding partition with a lead equivalent of 0.3 mmPb, the exposure dose reduced as 0.399 μSv. Therefore, mobile CT can be used in ICUs when appropriate shielding is provided.

BACKGROUND: Infants admitted to neonate intensive care units (NICUs) are placed in incubators to maintain body temperature and condition, which undergo normal radiographs and are exposed to radiation. Furthermore, different incubator structures in different hospitals exhibit varying object to image receptor distance (OID), source to image receptor distance (SID), presence of canopy, which results in variations in X-ray radiation conditions and doses absorbed by the neonatal patients. OBJECTIVE: To measure organ dose exposed to neonatal patient in different incubator settings. METHODS: A portable X-ray was performed on a neonatal patient placed in an incubator to identify disease progress, the injection path of the drug, and various factors. To minimize direct contact between neonatal patients and image receptor, radiologic technologists place the image receptor on a tray underneath the incubator and place the portable X-ray tube on top of the acrylic canopy of the incubators. SID and OID settings and value of organ dose exposed to the patient varied based on the incubator structure, and the organ absorbed dose was determined using Monte Carlo N-Particle (MCNP) simulation, PC-based Monte Carlo program (PCXMC) 2.0 simulation, and neonate phantoms. RESULTS: Evaluations of organ dose of neonatal patients in three hospitals with different incubator settings reveal that the average organ dose differs by 36% depending on change in OID and SID settings and reduces by 10% with an acrylic canopy. Therefore, owing to the presence of an acrylic canopy on the top of the incubator and the longer SID with the corresponding shorter OID, a lower dose was absorbed by organs of neonatal patient. CONCLUSION: Our results provide proof that proper incubator standard decreases organ dose to neonatal patient during continuously diagnostic X-ray procedure.

Purpose: The objective of this study was to assess the feasibility of incorporating virtual reality/augmented reality (VR/AR) programs into practical tests administered as part of the Korean Radiological Technologists Licensing Examination (KRTLE). This evaluation is grounded in a comprehensive survey that targeted enrolled students in departments of radiology across the nation.Methods: In total, 682 students from radiology departments across the nation were participants in the survey. An online survey platform was used, and the questionnaire was structured into 5 distinct sections and 27 questions. A frequency analysis for each section of the survey was conducted using IBM SPSS ver. 27.0.Results: Direct or indirect exposure to VR/AR content was reported by 67.7% of all respondents. Furthermore, 55.4% of the respondents expressed that VR/AR could be integrated into their classes, which signified a widespread acknowledgment of VR among the students. With regards to the integration of a VR/AR or mixed reality program into the practical tests for purposes of the KRTLE, a substantial amount of the respondents (57.3%) exhibited a positive inclination and recommended its introduction.Conclusion: The application of VR/AR programs within practical tests of the KRTLE will be used as an alternative for evaluating clinical examination procedures and validating job skills.