• Journal of the Korean Society of Radiology
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• v.16 no.1
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• pp.67-75
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• 2022

The aim of this study is to establish a new QC method that can simultaneously evaluate the resolution of the x/y plane and the z-axis by producing a phantom that can reflect exposure and reconstruction parameter of MDCT system. It was used with Aquilion ONE(Cannon Medical System, Otawara, Japan), and the examination was scanned using of 120 kV, 260 mA, and the D-FOV of 300 mm². It produced new SSP phantom modules in which two aluminum plates inclined at 45° to a vertical axis and a transverse axis to evaluate high contrast resolution of x/y plane and z axis. And it changed factors such as the algorithm, distance from gantry iso-center. All images were reconstructed in five steps from 0.6 mm to 10.0 mm slice thickness to measure resolution of x/y plane and z-axis. The image data measured FWHM and FWTM using Profile tool of Aquarius iNtusion Edition ver. 4.4.13 P6 software(Terarecon, California, USA), and analysed SPQI and signal intensity by ImageJ program(v1.53n, National Institutes of Health, USA). It decreased by 4.09~11.99%, 4.12~35.52%, and 4.70~37.64% in slice thickness of 2.5 mm, 5.0 mm, and 10.0 mm for evaluating the high contrast resolution of x/y plane according to distance from gantry iso-center. Therefore, the high contrast resolution of the x/y plane decreased when the distance from the iso-center increased or the slice thickness increased. Additionally, the slice thicknesses of 2.5 mm, 5.0 mm, and 10.0 mm with a high algorithm increased 74.83, 15.18 and 81.25%. The FWHM was almost constant on the measured SSP graph for evaluating the accuracy of slice thickness which represents the resolution of x/y plane and z-axis, but it was measured to be higher than the nominal slice thickness set by user. The FWHM and FWTM of z-axis with axial scan mode tended to increase significantly as the distance increased from gantry iso-center than the helical mode. Particularly, the thinner slice thickness that increased error range compare with the nominal slice thickness. The SPQI increased with thick slice thickness, and that was closer to 90% in the helical scan than the axial scan. In conclusion, by producing a phantom suitable for MDCT detectors and capable of quantitative resolution evaluation, it can be used as a specific method in the management of research quality and management of outdated equipment. Thus, it is expected to contribute greatly to the discrimination of lesions in the field of CT imaging.

• Journal of the Korean Orthopaedic Association
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• v.56 no.2
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• pp.150-156
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• 2021

Purpose: To determine how the location, displacement, intra-articular involvement, comminution of a 5th metatarsal base fracture affect results of early weight-bearing treatment. Materials and Methods: From January 2013 to July 2017, 34 cases of 34 patients diagnosed with a fracture of the zone I and II 5th metatarsal base were enrolled. The mean follow-up period was 13 months (6-15 months). One patient was excluded as a refracture during the follow-up period, and 33 patients underwent conservative treatment. Anteroposterior, lateral, and simple oblique radiography and computed tomography of the foot were performed to evaluate the location and displacement of the fracture, the degree of joint involvement, and comminution. In all 33 patients, a short leg cast or boot brace was selected immediately after the injury, tolerable weight bearing was allowed. If the pain disappeared, full weight bearing was performed after wearing a plain shoe or postoperative shoe. As a clinical result, the American Orthopedic Foot and Ankle Society (AOFAS) score was evaluated at the final follow-up. During outpatient follow-up, a simple radiograph of the foot was taken to confirm the time of radiological bone union and return to work. Results: Nine males and 24 females, with an average age of 48.7 years, were enrolled in the study. Twenty-four patients had zone I fractures, and nine patients had zone II fractures. Twenty-two out of 33 patients had a fracture displacement of 2 mm or more. Nine and five patients had joint involvement and comminution, respectively. There was a statistically significant return to work from zone I to zone II. The AOFAS score was excellent at the final follow-up and there was no significant difference. When classifying and comparing the degree of fracture displacement, joint involvement, and comminution, there were no significant differences in the radiological union time and return to work. In all cases, satisfactory results were obtained at the final follow-up. Conclusion: Satisfactory clinical results can be obtained by allowing early weight-bearing regardless of the fracture location, displacement, joint involvement, or comminution in zone I and II 5th metatarsal base fractures.

• Journal of the Korean Orthopaedic Association
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• v.55 no.6
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• pp.520-526
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• 2020

Purpose: The need for revision fusion surgery after spinal fusion has increased. A revision rod that connects to the previous rod was newly developed for revision surgery. The purpose of this study was to analyze the clinical and radiological results after spinal fusion revision surgery using revision rods. Materials and Methods: Twenty-one patients who underwent revision fusion surgery after spinal fusion in two university hospitals with minimum 1 year follow-up were reviewed. This study assessed 16 cases of adjacent-segment disease, four cases of thoracolumbar fracture, and one case of ossification of ligament flavum. The Oswestry Disability Index (ODI) and numerical rating scale (NRS) were evaluated as clinical outcomes, and the union rate, lordosis or kyphosis of the revision level, lumbar lordosis, T5-12 kyphosis, and proximal junctional kyphosis angle were evaluated as the radiological outcomes. Results: The average ODI was 54.6±12.5 before surgery and improved to 29.8±16.5 at the final follow-up. The NRS for back pain and leg pain was 5.0±1.7 and 6.4±2.0 before surgery, which changed to 2.9±1.6 and 2.9±2.2 at the final follow-up. Lumbar lordosis was 18.1°±11.9° before surgery and 21.1°±10.3° at the final follow-up. Proximal junctional kyphosis was 10.8°±10.1° before surgery, and 9.2°±10.5° at the final follow-up. These angles were not changed significantly after surgery. Bony union was successful in all cases except for one case who underwent posterolateral fusion. Conclusion: Revision surgery using a newly developed revision rod on the thoracolumbar spine achieved good clinical outcomes with successful bony union. No problems with the newly developed revision rod were encountered.

• 한국노년학
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• v.40 no.4
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• pp.729-746
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• 2020

For the development and better use of information and communication technology(ICT) for promoting health and quality of life in older people, it is important to understand personal factors associated with ICT use. The aims of this study were to describe the pattern of ICT use according to health characteristics of elderly and to investigate significant factors related to ICT use among three age groups. The data of 2017 National Survey of Older Koreans was used for analysis and 10,058 of older adults aged 65 and over were included for study participants. As results, first, the young old(65~74) used more functions of ICT than the middle-old(75~84) and the old-old(85 and over). Second, ICT was more used among older people with good conditions in chronic disease, subjective health, cognition, depression, vision, hearing, walking and IADL. Third, higher prevalence of ICT use was significantly associated with age, education, household income, subjective health, depression, cognitive function, vision limitation and walking limitation. Fourth, factors influencing the use of ICT were a little different among three age groups. For the young-old(65~74), subjective health, depression, cognitive decline, walking limitation, and IADL disability were significant factors affecting on ICT use. For the middle-old(75-84), subjective health, depression, cognitive decline, vision, hearing, and walking limitation were related with their ICT use. For the old-old(85 and over), only cognitive function and depression were associated with their ICT use. Based on these results, this study suggested the need to consider multiple health conditions for developing and using ICT for older adults.

• Journal of Nutrition and Health
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• v.55 no.2
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• pp.278-295
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• 2022

Purpose: This study was undertaken to revise and update the Nutrition Quotient (NQ) for Korean adults, a tool used to evaluate dietary quality and behavior. Methods: The first 31 items of the measurable food behavior checklist were adopted based on considerations of the previous NQ checklist, recent literature reviews, national nutrition policies, and recommendations. A pilot survey was conducted on 100 adults aged 19 to 64 residing in Seoul and Gyeonggi Province from March to April 2021 using a provisional 26- item checklist. Pilot survey data were analyzed using factor analysis and frequency analysis to determine whether checklist items were well organized and responses to questions were well distributed, respectively. As a result, the number of items on the food behavior checklist was reduced to 23 for the nationwide survey, which was administered to 1,000 adults (470 men and 530 women) aged 19 to 64 from May to August 2021. The construct validity of the developed NQ (NQ-2021) was assessed using confirmatory factor analysis, linear structural relations. Results: Eighteen items in 3 categories, that is, balance (8 items), moderation (6 items), and practice (4 items), were finally included in NQ-2021 food behavior checklist. 'Balance' items addressed the intake frequencies of essential foods, 'moderation' items the frequencies of unhealthy food intakes or behaviors, and 'practice' items addressed eating behaviors. Items and categories were weighted using standardized path coefficients to calculate NQ-2021 scores. Conclusion: The updated NQ-2021 appears to be suitable for easily and quickly assessing the diet qualities and behaviors of Korean adults.

• Journal of the Korean Society of Radiology
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• v.17 no.1
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• pp.149-156
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• 2023

The purpose of this study is to compare of growth and chlorophyl between old-barley seed (OBS, 2019) and New-barley seed (NBS, 2020) exposed by X-ray. After germination the OBS and NBS, experimental group was exposed by 30 Gy X-ray using linear accelerator (Clinac IS, VERIAN, USA), by 6 MV X-ray, SSD 100 cm, 18 × 10 cm², 600 MU/min. Length was measured every day until 9th day, and chlorophyl was analyzed using spectrophotometer(uv-1800, shimadzu, japan) after measuring weight in 9th day. Data analysis was performed the Independent T-test using SPSS ver 26.0(Chicago, IL, USA). NBS grow more faster than OBS in control group, but OBS grow more faster than NBS in experimental group. Length of control group was longer significantly every day than that of experimental group in OBS. NBS weighted more than OBS in control group, but OBS weighted more than NBS in experimental group. In comparing chlorophyl density, NBS high more than OBS in control group as well as experimental group. Growth and weight of OBS was effected more those than NBS by X-ray, but NBS in chlorophyl by X-ray. It is expected to be used as basic data for future X-ray research in barley seed.

• Journal of Nutrition and Health
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• v.55 no.3
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• pp.359-375
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• 2022

Purpose: Adult Korean men belonging to the main economically active population are known to have long sedentary hours. This study was undertaken to determine the difference and relevance of sedentary hours on the nutrition, diet, and health status of adult men, and to suggest how to prevent health risk factors. Methods: Subjects (n = 1,068) were classified into 4 groups based on their sedentary hours, ranging from the first quartile (Q1) having the least hours spent sitting, to the fourth quartile (Q4) spending the longest hours. Results: Subjects belonging to Q4 had the lowest average age, the largest waist circumference, and the highest level of education. Among those engaged in economic activities, the ratio of white-collar workers was significantly higher in Q4. Accordingly, the rate of not doing high-intensity or moderate-intensity physical activity while working was also the highest in Q4. A significant difference was obtained in the drinking frequency between groups, but this was found to be associated with the average working hours rather than sedentary hours. The proportion of not doing aerobic exercise was higher with longer sitting hours. The highest diagnosis of diabetes (8.8%) was obtained in the Q4 group. Among the factors related to cardiovascular disease, only low density lipoprotein-cholesterol showed a significant difference, with Q4 being significantly higher than Q1. Considering energy and nutrient intake, vitamin B₁ and calcium intake were the lowest in the group with the longest sitting hours, as well as the least consumption of vitamin C than the recommended estimated average requirement. Conclusion: The results of this study suggest that the health and nutritional status of Korean adult men are affected by sedentary hours. This should be recognized as a health risk factor and guidelines need to be developed for sedentary lifestyle management.

• Journal of the Korean Society of Radiology
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• v.17 no.4
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• pp.489-495
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• 2023

Radiation shielding facilities are constructed in locations where diagnostic radiation generators are installed, with the aim of preventing exposure for patients and radiation workers. The purpose of this study is seek to compare and validate the trend of attenuation thickness of lead, the primary material in these radiation shielding facilities, at different maximum tube voltages by Monte Carlo simulations and measurement. We employed the Monte Carlo N-Particle 6 simulation code. Within this simulation, we set a lead shielding arrangement, where the distance between the source and the lead sheet was set at 100 cm and the field of view was set at 10 × 10 cm². Additionally, we varied the tube voltages to encompass 80, 100, 120, and 140 kVp. We calculated energy spectra for each respective tube voltage and applied them in the simulations. Lead thicknesses corresponding to attenuation rates of 50, 70, 90, and 95% were determined for tube voltages of 80, 100, 120, and 140 kVp. For 80 kVp, the calculated thicknesses for these attenuation rates were 0.03, 0.08, 0.21, and 0.33 mm, respectively. For 100 kVp, the values were 0.05, 0.12, 0.30, and 0.50 mm. Similarly, for 120 kVp, they were 0.06, 0.14, 0.38, and 0.56 mm. Lastly, at 140 kVp, the corresponding thicknesses were 0.08, 0.16, 0.42, and 0.61 mm. Measurements were conducted to validate the calculated lead thicknesses. The radiation generator employed was the GE Healthcare Discovery XR 656, and the dosimeter used was the IBA MagicMax. The experimental results showed that at 80 kVp, the attenuation rates for different thicknesses were 43.56, 70.33, 89.85, and 93.05%, respectively. Similarly, at 100 kVp, the rates were 52.49, 72.26, 86.31, and 92.17%. For 120 kVp, the attenuation rates were 48.26, 71.18, 87.30, and 91.56%. Lastly, at 140 kVp, they were measured 50.45, 68.75, 89.95, and 91.65%. Upon comparing the simulation and experimental results, it was confirmed that the differences between the two values were within an average of approximately 3%. These research findings serve to validate the reliability of Monte Carlo simulations and could be employed as fundamental data for future radiation shielding facility construction.

• Journal of the Korean Society of Radiology
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• v.17 no.3
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• pp.305-314
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• 2023

With the development of medical technology and radiation treatment equipment, the frequency of high-precision radiation therapy such as intensity modulation radiation therapy has increased. Image-guided radiation therapy has become essential for radiation therapy in precise and complex treatment plans. In particular, with the introduction of imaging equipment for diagnosis in a linear accelerator, CBCT scanning became possible, which made it possible to calibrate and correct the patient's posture through 3D images. Although more precise reproduction of the patient's posture has become possible, the exposure dose delivered to the patient during the image acquisition process cannot be ignored. Radiation optimization is necessary in the field of radiation therapy, and efforts to reduce exposure are necessary. However, when acquiring 3D CBCT images by changing the imaging conditions to reduce exposure, there should be no image quality or artefacts that would make it impossible to align the patient's position. In this study, Rando phantom was used to scan and evaluate images for each shooting condition. The highest SNR was obtained at 100 kV 80 mA 25 ms F1 filter 180°. As the tube voltage and tube current increased, the noise decreased, and the bowtie filter showed the optimal effect at high tube current. Based on the actual scanned images, it was confirmed that patient alignment was possible under all imaging conditions, and that image-guided radiation therapy for patient alignment was possible under the condition of 70 kV 10 mA 20 ms F0 filter 180°, which showed the lowest SNR. In this study, image evaluation was conducted according to the imaging conditions, and low tube voltage, tube current, and small rotation angle scan are expected to be effective in reducing radiation exposure. Based on this, the patient's exposure dose should be kept as low as possible during CBCT imaging.

• Journal of the Korean Society of Radiology
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• v.18 no.3
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• pp.293-300
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• 2024

On October 31, 2023, the revision of the Medical Technologist Act made it mandatory to complete field training courses in order to obtain a license as a radiologic technologist. Therefore, we would like to survey the actual situation of field training in medical institutions to inform the revised Medical Technologist Act and propose improvement measures to increase the effectiveness of field training. A survey was conducted from March to April, 2023, among radiologic technologists working in medical institutions. The questionnaire was sent through a form on a domestic portal site, Company N, and 120 respondents completed it. Eighty-two respondents, or 68.3 percent, had experience in educating on-the-job training students. 58% of the respondents were aware of the fact that the amendment to the Act on Medical Technologist etc. made field training mandatory to obtain a radiologic technologist license. In accordance with Article 9 of the Medical Technologist Act, which prohibits unlicensed persons from practicing, 50% of the respondents were aware that those who are in training to complete an education course equivalent to the license they are seeking to obtain at a university or other institution are allowed to practice as medical Technologists. When asked what is currently taught during fieldwork, 6% of respondents said that they are required to perform radiation-generating activities in addition to observing, guiding patients, and positioning and moving patients. When asked about the future direction of education as fieldwork becomes mandatory for licensure, 77% of respondents said that they will teach more than they currently do. When asked about the appropriate total length of fieldwork, 35% said 12 weeks and 480 hours, 33% said 8 weeks and 320 hours, and 27% said 16 weeks and 640 hours. It can be seen that the current on-the-job training is inadequate according to various regulations, and students' satisfaction is low. However, with the revision of the Act on Medical Technologists, field training has become mandatory to obtain a license as a radiologist, and it is necessary to improve the educational conditions of field training. Therefore, it is necessary to comply with the Nuclear Safety Act and the Rules on the Safety Management of Diagnostic Radiation Generating Devices, introduce standardized training objectives and evaluation systems, designate training hospitals and radiologists in charge of training, and introduce extended training periods and simulation exercises to internalize field training.