• The Journal of the Convergence on Culture Technology
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• v.10 no.3
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• pp.819-825
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• 2024

The reason for recording dose data when using a diagnostic radiation source is to record and manage the dose to healthcare personnel and patients. The purpose of this study was to verify the difference in radiation dose when using diagnostic radiation generating devices and to inform users' awareness of dose reduction through measurement and analysis of dose in situations with and without shielding. The dose analysis of each equipment for two Korean C-arms and two German C-arms showed that the Korean FPD type C-arm had the highest dose value, followed by the German I.I type C-arm, German FPD type C-arm, Korean, and I.I type C-arm. The results of the dose analysis with and without shielding showed that the dose to the human phantom in a normal atmosphere increased by about 2 times due to scattered radiation, but the dose to the human phantom was reduced by about 5 times by wearing a shield (0.5mm/lead apron). More important than the management of radiation dose is the study of how to reduce exposure when using radiation, and since the radiation dose output from different equipment is different, it is necessary to provide dose information with and without shielding.

• Journal of the Korean Society of Radiology
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• v.7 no.5
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• pp.321-331
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• 2013

The purpose of this study was to investigate factors of perception by inpatients of the radiology department about exposure to radioactivity at the time of radioactive examination, providing basic information for making educational materials aimed to change their perception. Most of those patients, 65.5% responded that CT was a type of radioactive examination bringing highest exposure to radiosensitivity. Most of the subjects, 56.1% said that a body part most vulnerable to exposure to radiosensitivity was the genital gland at the time of radiosensitivity examination. And most of the participants, or 26.3% responded that they obtained information about radiation from TVs or newspapers. Among the surveyed patients, men were higher in scores for factors of the perception of radiation such as recognition of radiation, harmfulness of radiation, psychological state at the time of radioactive examination, prevention of exposure to radioactivity and necessity of radiation that women were, with statistically significant differences between the two groups. These findings suggest that it is urgently needed to develop an education program which helps patients better perceive exposure to radioactivity and that radiologists should be very careful to reduce the does of that exposure. If patients better perceive radiation, they would be less anxious and less exposed to radioactivity when receiving the radioactive examination.

• Journal of the Korean Society of Radiology
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• v.9 no.6
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• pp.381-392
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• 2015

The purpose of this study was to investigate factors of perception by inpatients of the Primary Health Care institutions about exposure to radioactivity at the time of radioactive examination, providing basic information for making educational materials aimed to change their perception. Most of those patients, 65.5% responded that CT was a type of radioactive examination bringing highest exposure to radiosensitivity. Most of the subjects, 56.1% said that a body part most vulnerable to exposure to radiosensitivity was the genital gland at the time of radiosensitivity examination. And most of the participants, or 26.3% responded that they obtained information about radiation from TVs or newspapers. Among the surveyed patients, men were higher in scores for factors of the perception of radiation such as recognition of radiation, harmfulness of radiation, psychological state at the time of radioactive examination, prevention of exposure to radioactivity and necessity of radiation that women were, with statistically significant differences between the two groups. These findings suggest that it is urgently needed to develop an education program which helps patients better perceive exposure to radioactivity and that radiologists should be very careful to reduce the does of that exposure. If patients better perceive radiation, they would be less anxious and less exposed to radioactivity when receiving the radioactive examination.

• Journal of Radiation Protection and Research
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• v.37 no.1
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• pp.25-34
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• 2012

To know which parameters were acceptable for achieving lowest radiation exposure to the patients and highest image quality at the diagnostic X-ray radiography, we measured the patient radiation dose and image quality in transmitted PACS (Picture Archiving and Communication System) at variable combinations of the added filters. As a result, the Dose Area Product (DAP: $mGy{\cdot}cm^2$) and Entrance Surface Doses (ESDs: $mGy$) was lowest at 1 mmAl + 0.2 mmCu and highest at 0 mmAl. The histogram of the image quality by transmitted PACS was not significantly different at variable combinations of exposure parameters on the MATLAB. In conclusion, this study can be helpful for expecting radiation dose-exposure and control exposure parameters for the diagnostic X-ray radiography.

• Journal of the Korean Society of Radiology
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• v.6 no.3
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• pp.201-206
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• 2012

Effect of prenatal ultrasound diagnosis have serious damage for the possibility has been reported very low. Long time ultrasound scan can rise the temperature in body tissues and affect the physical. Changes in body temperature have been studied with ultrasound scan time. Fetal ultrasonography were evaluated without the influence of time. The findings, ultrasound scan time in 40 minutes the temperature was reduced. 50 minute tissue temperature rose more than $1^{\circ}C$. If within 40 minutes of ultrasound to be safe guess

• The Journal of Korean Society for Radiation Therapy
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• v.26 no.1
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• pp.127-135
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• 2014

Purpose : By taking advantage of each imaging modality, the use of fused CT/MRI image has increased in prostate cancer radiation therapy. However, fusion uncertainty may cause partial target miss or normal organ overdose. In order to complement such limitation, our hospital acquired MRI image (Planning MRI) by setting up patients with the same fixing tool and posture as CT simulation. This study aims to evaluate the usefulness of the Planning MRI through comparing and analyzing the diagnostic MRI image and Planning MRI image. Materials and Methods : This study targeted 10 patients who had been diagnosed with prostate cancer and prescribed nonhormone and definitive RT 70 Gy/28 fx from August 2011 to July 2013. Each patient had both CT and MRI simulations. The MRI images were acquired within one half hour after the CT simulation. The acquired CT/MRI images were fused primarily based on bony structure matching. This study measured the volume of prostate in the images of Planning MRI and diagnostic MRI. The diameters at the craniocaudal, anteroposterior and left-to-right directions from the center of prostate were measured in order to compare changes in the shape of prostate. Results : As a result of comparing the volume of prostate in the images of Planning MRI and diagnostic MRI, they were found to be $25.01cm^3$(range $15.84-34.75cm^3$) and $25.05cm^3$(range $15.28-35.88cm^3$) on average respectively. The diagnostic MRI had an increase of 0.12 % as compared with the Planning MRI. On the planning MRI, there was an increase in the volume by $7.46cm^3$(29 %) at the transition zone directions, and there was a decrease in the volume by $8.52cm^3$(34 %) in the peripheral zone direction. As a result of measuring the diameters at the craniocaudal, anteroposterior and left-to-right directions in the prostate, the Planning MRI was found to have on average 3.82cm, 2.38cm and 4.59cm respectively and the diagnostic MRI was found to have on average 3.37cm, 2.76cm and 4.51cm respectively. All three prostate diameters changed and the change was significant in the Planning MRI. On average, the anteroposterior prostate diameter decrease by 0.38cm(13 %). The mean right-to-left and craniocaudal diameter increased by 0.08cm(1.6 %) and 0.45cm(13 %), respectively. Conclusion : Based on the results of this study, it was found that the total volumes of prostate in the Planning MRI and the diagnostic MRI were not significantly different. However, there was a change in the shape and partial volume of prostate due to the insertion of prostate balloon tube to the rectum. Thus, if the Planning MRI images were used when conducting the fusion of CT/MRI images, it would be possible to include the target in the CTV without a loss as much as the increased volume in the transition zone. Also, it would be possible to reduce the radiation dose delivered to the rectum through separating more clearly the reduction of peripheral zone volume. Therefore, the author of this study believes that acquisition of Planning MRI image should be made to ensure target delineation and localization accuracy.

• Journal of the Korea Safety Management & Science
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• v.17 no.3
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• pp.215-219
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• 2015

The purpose in this study is to investigate CT number difference between conventional CT and CT simulator. It shows good correlation in CT number on the muscle, bone, and air. However, in the liver, lungs and water, the low correlation was detected. This result can become the good index for the direction of the distribution of dose difference research between CT equipment for using the computerized radiation therapy planning system.

• Radiation Oncology Journal
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• v.10 no.1
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• pp.101-105
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• 1992

Authors performed a stereotactic radiosurgery with multiple noncoplanar convergent photon beams of linear accelerator (NELAC-1018 18 MeV, NEC) using a specially designed Yeungnam localization device for two patients with recurrent glioblastoma multiforme. One patient had 2 cm sized and the other 4 cm sized mass on the CT images. After single session of treatment with 15 and 20 Gy, headache was improved in a few days after radiosurgery with no remarkable untoward reactions. Our experience with these two patients were encouraging and we found that our localization device, which is easily adjustable and inexpensive, could be a valuable tool for stereotactic radiosurgery particularly in the treatment of recurrent brain tumor.

• Journal of the Korean Society of Radiology
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• v.6 no.5
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• pp.389-394
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• 2012

In this study, based on IEC 60601-2-54 standard load conditions presented in the limited interval over the air kerma at the absolute linearity closely evaluated by measuring the X-ray results were as follows: 10 units targeted all Diagnostic X-ray generating device (DR) presented in the IEC 60601-2-54 standard linearity of air kerma emerged as inappropriate, the general evaluation of the dose linearity from four in the top 50% and 80 kVp % of the two measurement series were as irrelevant all the rest from six of the top tube voltage of 50% and 80% of the two measurement series, appeared in all suitable. Presented in IEC 60601-2-54 standard dose linearity testing and conventional linearity tests showed many differences. IEC 60601-2-54 standard linearity in the proposed international standards of air kerma is the recommendation of the existing dose linearity considerably more feasible, and to quantify the amount of radiation as the standard suggested by the standard IEC 60601-2-54 air kerma of a diagnostic X-ray imaging device linearity performance management is considered key elements in the critical appraisal.

• Journal of the Korean Society of Radiology
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• v.13 no.2
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• pp.227-232
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• 2019

MRI examination for patients with metal objects has in poor image quality. Metallic implants can result in poor image because magnetic susceptibility causes signal loss and distortion and makes poor imaging, which is called magnetic susceptibility artifact or metal artifact. There are several approaches to reduce metal artifacts. In this study, we study the reduction of metal artifact by VAT and SEMAC techniques. A metal implant used for orthopedic surgery was attached to the phatom and the distortion caused by the artifact was measured under T1WI and T2WI protocols. Several techniques of VAT only and VAT and SEMAC for the reduction of metal artifact were compared. The metal artifact showed a reduction of at least 8% to a maximum of 26% in the VAT-SEMAC. The VAT-SEMAC technique can be applied to patients with orthopedic implants to improve image quality. If scan time and image quality are simultaneously considered in VAT-SEMAC technique, metal artifact will be reduced in clinical practice.