Showing papers in "Journal of the Korean Society of Radiology in 2013"

A Study on Perception by Examines of the Radiology Department about Exposure to Radioactivity

Abstract: 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.

Intracranial Extra-Axial Ependymoma in the Ambient Cistern That Initially Presented as Calcification: A Report of Case

Abstract: Ependymomas usually occur in intraventricular or intraspinal locations. Intracranial extraaxial ependymomas (IEAEs) are very rare. Here, we present an unusual case of an IEAE in 25-year-old man. The patient experienced head trauma two and half years prior to presentation, at which time brain computed tomography (CT) showed only a dense calcification in the left ambient cistern. After two and a half years, follow up brain CT and magnetic resonance imaging depicted interval growth of a calcified mass with cystic change. The tumor was successfully treated surgically, and the pathologic examination confirmed ependymoma. Index terms Extra-Axial Intracranial Ependymoma

Sarcomatoid Carcinoma of the Small Intestine: A Case Report and Review of the Literature

Abstract: Sarcomatoid carcinomas are rare biphasic tumors composed of mixed malignant epithelial and mesenchymal cells. A few cases for small intestinal sarcomatoid carcinoma were reported. Moreover, most of the cases are focused on the pathologic review. We experienced a case of monophasic sarcomatoid carcinoma arising in the jejunum in a 78-year-old man. In this case, CT showed fungating mass with central necrosis in the jejunum. We also reviewed literatures on sarcomatoid carcinoma that arises in the small intestine.

Cumulative Radiation Exposures during Diagnosis and Treatments with Diagnostic Radiology Tools: In Patient with Hepatocellular Carcinoma

Abstract: This paper was supported by a research grant from the General Electric Healthcare, 2010. Purpose: To evaluate the cumulative radiation dose for diagnosis and treatment with diagnostic radiology tools for patients with hepatocellular carcinoma. Materials and Methods: Cumulative radiation dose of 98 patients with hepatocellular carcinoma were examined by diagnostic CT, CT for follow-up, once or repeated transarterial chemoembolization (TACE), and X-ray examinations. Thus, we calculated the total cumulative effective doses per patient. Results: The mean follow-up periods were 85 (51-102) weeks. A total of 565 CT scans, 262 TACEs, and 1679 X-ray examinations were enrolled. Cumulative effective dose values per person of 91.4 ± 50.6 (8.4-244.7) mSv, 49.2 ± 44.7 (5.3-247.6) mSv, and 3.6 ± 4.7 (0.02-22.04) mSv were measured for CT, TACE, and X-ray examinations. Total cumulative effective dose values per person were measured as 144.2 ± 87.4 (15.4-513.5) mSv. Conclusion: The patient who underwent TACE are exposed to pretty high dose radiations, thus, significant efforts to reduce the radiation dose are necessary.

Analysis of dose reduction of surrounding patients in Portable X-ray

Abstract: Nowadays, the medical system towards patients changes into the medical services. As the human rights are improved and the capitalism is enlarged, the rights and needs o f patients are gradually increasing. Also, based on this change, several systems in hospitals are revised accord ing to the convenience and needs of patients. Thus, the cases of mobile portable among examinations are getti ng augmented. Because the number of mobile portable examinations in patient’s room, intensive care unit, o perating room and recovery room increases, neighboring patients are unnecessarily exposed to radiation so that the examination is legally regulated. Hospitals have to specify that “In case that the examination is taken out of the operating room, emergency room or intensive care units, the portable medical X-ray protec tive blocks should be set” in accordance with the standards of radiation protective facility in diagnostic ra diological system. Some keep this regulation well, but mostly they do not keep. In this study, we shielded around the Collimator where the radiation is detected and then checked the change of dose regarding that of angles in portable tube and collimator before and after shielding. Moreover, we tried to figure out the effects of shie lding on dose according to the distance change between patients’ beds. As a result, the neighboring areas arou nd the collimator are affected by the shielding. After shielding, the radiation is blocked 20% more than doing n othing. When doing the portable examination, the exposure doses are increased 0°, 90° and 45°in order. At th e time when the angle is set, the change of doses around the collimator decline after shielding. In additio n, the exposure doses related to the distance of beds are less at 1m than 0.5m. In consideration of the shieldin g effects, putting the beds as far as possible is the best way to block the radiation, which is close to 100%. Ne xt thing is shielding the collimator and its effect is about 20%, and it is more or less 10% by controlling the angles. When taking the portable examination, it is better to keep the patients and guardians fa r enough away to reduce the exposure doses. However, in case that the bed is fixed and the patient cannot m ove, it is suggested to shield around the collimator. Furthermore, 90°of collimator and tube is recommend ed. If it is not possible, the examination should be taken at 0°and 45°is better to be disallowed. The rad iation-related workers should be aware of above results, and apply them to themselves in practice. Also, it is recommended to carry out researches and try hard to figure out the ways of reducing the exposure doses and shielding the radiation effectively.

생활주변방사선안전관리법 시행에 따른 항목별 선량 분석

Abstract: The study attempted to analyze items presented in Act on safety control of radioactive rays around living environment, which has been recently enacted. The test items have been divided into cosmic rays, cosmic rays, terrestrial radiation, and byproduct, etc., and the selected locations for measurement included an airplane at 8000m in the air, mountainous area at 1000m above sea level, 15m-underground building, construction site, and seashore at 0m altitude. The test showed that, based on cosmic rays, plane at 8000m in the air had 4.91mSv/y of effective dose per year. The mountainous area at 1000m above sea level, which was chosen to measure cosmic rays and terrestrial radiation, was measured 0.35mSv higher than the seashore at 0m in altitude due to the effect of cosmic rays and terrestrial radiation from the greater height above sea level. The construction site, chosen as a location to measure byproduct, showed the highest value among the items with 6.66mSv, which is as 10times high as that of a completed building. The seashore at 0m in altitude had 5.96mSv, and, 15m-underground building, based on terrestrial radiation, was the lowest with 4.91mSv. This suggests that, despite the assumption that terrestrial radiation will have greater effect deeper underground, it did not affect inside the building significantly. This study showed that the items presented in Act on safety control of radioactive rays around living environment were not close to effective dose limit for radiation workers proposed by ICRP. However, they were between 4 and 7 times higher than that for general public. This suggests that there should be continuous research on and attention to Safe Management of Daily Surrounding Radiation Act, which is still at its beginning stage.

Renal Metastasis from Primary Cervical Cancer: A Case Report

Abstract: Copyrights © 2013 The Korean Society of Radiology 서론 신장으로의 악성종양 원격 전이는 주로 혈행성으로 파급되며 약 반수 이상에서 양측성 다발성의 형태로 나타난다(1) 다양한 타장기 원발암이 신장으로 전이할 수 있으나 알려진 원발암으 로는 림프종과 폐암이 가장 많고, 원발성 자궁경부암의 신장 전이는 극히 드물다 원발성 자궁경부암의 타장기 원격전이는 원발암의 병기와 조 직학적 악성도 및 치료여부에 따라 다양한 빈도로 나타날 수 있 으나 일반적으로 골반 내 장기와 림프절로의 원격 전이가 가장 흔하다(1-3) 신장으로의 원격전이는 문헌 검색상 2007년까지 총 8예가 보고되었으며, 국내에서는 보고된 바 없다 보고된 자 궁경부암 신장전이의 영상의학적 소견은 약 반수에서 양측신장 의 다발성 결절형태로 보였으며, 이 경우 신장농양과 비슷한 소 견을 보였다(1, 4) 반면 저자들은 항암화학방사선요법 후 추 적관찰 중 일측 신장에서 발견된 단일 종괴 형태의 전이성 자궁 경부암 1예를 경험하였으며, 이는 영상의학적 검사상 신장농양 보다는 신우에서 기원한 이행상피세포암과 비슷한 소견을 보였 다 이에 영상소견을 문헌고찰과 함께 보고하고자 한다 증례 보고

Regional Cortical Hyperperfusion on Perfusion CT during Postictal Motor Deficit: A Case Report

Abstract: Postictal neurologic deficit is a well-known complication of focal or generalized seizures mimicking clinical manifestation of a stroke; however, it can be misdiagnosed as a stroke (1-3) Thus, in an acute setting, imaging studies are the most useful means for making the correct diagnosis (3) To our knowledge, there were a few reports of cortical hyperperfusion during postictal motor deficit in the literature We report a patient who was presented with postictal right hemiparesis accompanied by perfusion and diffusion abnormalities in the left parietal cortical areas Our case suggests that Todd’s paralysis may reveal transient perfusion and diffusion abnormalities; this report can be helpful for making an accurate diagnosis in patients with acute neurologic deficits

A Study on the Improvement of Evaluation Methods and Standards for Simulation Evaluation of Computed Tomography

Abstract: In foreign countries, the impotance of quality assurance (QA) is increasing, whereas QA evaluation standards are not established properly in Korea. Thus this study was conducted to suggest improved QA evaluation standards and methods by studying/comparing/analyzing the literature in both Korea and foreign countries and prove its suitability through simulated evaluation. result of research in south korea, much check list using the evaluation method subjective, the evaluation of accuracy and reproducibility is meausred in the number of missing. Therefore, attempts to present a clear reference evaluation and objective way to solve the problem, examined the accuracy and reproducibility and 10times of measurement. The results of the simulated evaluation satisfied both proposed evaluation standards and methods. However the QA evaluation standards and methods for the items that are implemented only in Korea and high-contrast spatial resolution could have been established. In this regard, there is a need of further studies on the establishment of QA evaluation standards and methods that suits Korean situation.

Additive Manufacturing of Patient-specific Femur Via 3D Printer Using Computed Tomography Images

Abstract: Femur is the largest bone in the human body which supports the weight of body. A long pipeline shape of femur has little cancellous bone, so that regeneration is difficult when fracture happens. The fracture caused by an accident most frequently occurs at diaphysis. IM Nailing is the surgical method that implants an IM Nail into a medullary cavity for the fixation of fracture parts. However, a secondary fracture may happen if an IM Nail does not penetrate at the center of femur. In this study, a patient-specific femur was manufactured by a 3D printer using the computed tomography images scanned before surgery, which was used for the simulation of IM Nailing. It is expected that this result may prevent the secondary damage, reduce surgical operation time, and increase the precision.

The Optimum of Respiratory Phase Using the Motion Range of the Diaphragm: Focus on Respiratory Gated Radiotherapy of Lung Cancer

Abstract: This study was to analyze quantitatively movement of planning target volume (PTV) and change of PTV volume through movement of diaphragm according to breathing phase. The purpose of present study was to investigate optimized respiration phase for radiation therapy of lung cancer. Simulated breathing training was performed in order to minimize systematic errors which is caused non-specific or irregular breathing. We performed 4-dimensional computed tomography (4DCTi) in accordance with each respiratory phase in the normalized respiratory gated radiation therapy procedures, then not only defined PTVi in 0 ~ 90%, 30 ~ 70% and 40 ~ 60% in the reconstructed 4DCTi images but analyzed quantitatively movement and changes of volume in PTVi. As a results, average respiratory cycle was seconds by simulated breathing training. R2-value which is expressed as concordance between clinically induced expected value and actual measured value, was almost 1. There was a statistically significant. And also movement of PTVi according to each respiration phase 0 ~ 90%, 30 ~ 70% and 40 ~ 60% were , and respectively. Change of volume in PTVi of respiration phase 30 ~ 70% was decreased by and 40 ~ 60% was decreased by . In conclusion, PTVi movement and volume change was reduced, when we apply a short breathing phase (40 ~ 60%: 30% duty cycle) range. Furthermore, PTVi margin considered respiration was not only within 4mm but able to get uniformity of dose.

블라인드 테스트를 통한 요추 검사 시 조사 조건의 최적화 연구

Abstract: This study intended to investigate the optimum conditions for lumbar test that has the highest level of irradiation conditions among general test sites. To to this, the most widely used irradiation conditions in terms of statistics were set as standards; test groups applied with DMF were selected; tests groups suitable for clinical trials were selected by using suggested patient dose. Blind tests were conducted by 10 specialists and radiologists. The results suggested that under the optimum conditions, the radiation dose reduction of 2.09 mGy, 4.42 mGy and 3.65 mGy can be achieved in forward-backward test, lateral test and 4-direction test, respectively. There is a need of further studies on the optimization of irradiation conditions in accordance with the conditions of patients.

Dose Evaluation of Childhood Leukemia in Total Body Irradiation

Abstract: Total body irradiation in the treatment of childhood leukemia, which is one of the pre-treatment with stem cell transplantation is being used, the current organization using compensators are treated. However, under the terms of the compensator organization long-term impact on the human body, it is difficult to assess directly. In this study, we use the mathematical simulation of radiation exposures body energy and the distance to the crew and the patient (source surface distance, SSD), and patients with tissue compensators change of the distance along the body of the organ doses were evaluated. As a result, the surface dose of energy 4 MV, SSD 280 cm, tissue compensators and the patient when the distance 30 cm 5.84 G / min showed the highest levels. In addition, patients with tissue compensators and the distance apart when 30 cm TBI represents the ideal dose distribution was found.

Denoising of Digital Mammography Images Using Wavelet Transform

Abstract: The optimum exposure parameters are found when examined using the automatic mode in FFDM. improve the image quality by applying denoising algorithm and propose methods to reduce AGD(Average Grandular Dose) a patient can receive. For the experiment, Nuclear Associates Model 18-222 phantom was the used, and the entrance dose and AGD were measured. And then, Signal, Noise, SNR and FOM(Figure of Merit) were measured, compared and analyzed image denoising before and after. As the experiment result, first, SNR was the highest at Mo/Mo 23kVp and W/Rh 35kvp was the lowest for the average glandular dose. It showed to use 28kVp of W/Rh to be the best through the result of FOM. SNR was the highest at Mo/Mo 23kVp(image denoising), and it showed to W/Rh and 28kVp to be the best in the FOM result which AGD was considered at the same time. By the image denoising, it is possible to reduce noise while maintain important information in the image.

치과 파노라마 촬영에서 환자의 피폭선량에 관한 연구

Abstract: This study estimate radiation biological danger factor by measuring patient's exposed dose and propose the low way of patient's exposed dose in panoramic radiography. We seek correcting constant of OSL dosimeter for minimize the error of exposed dose's measurement and measure the Left, Right crystalline lens, thyroid, directly included upper, lower lips, the maxillary bone and the center of photographing that indirect included in panoramic radiography by using the human body model standard phantom advised in ICRP. In result, the center of photographing's level of radiation maximum value is 413.67±6.53 μGy and each upper, lower lips is 217.80±2.98 μGy, 215.33±2.61 μGy. Also in panoramic radiography, indirect included Left, Right crystalline lens's level of radiation are 30.73±2.34 μGy, 31.87±2.50 μGy, and thyroid's level of measured exposed dose can cause effect of radiation biological and we need justifiable analysis about radiation defense rule and substantiation advised international organization for the low way of patient's exposed dose in panoramic radiography of dental clinic and we judge need the additional study about radiation defense organization for protect the systematize protocol's finance and around internal organs for minimize until accepted by many people that is technological, economical and social fact by using panoramic measurement.

몬테카를로 시뮬레이션을 통한 바륨화합물의 의료방사선 차폐능 비교 분석

Abstract: This study made a tentative estimation of the shielding rate of barium compound by thickness through monte carlo simulation to apply medical radiation shielding products that can replace existing lead. Barium sulfate(BaSO₄) was used for the shielding material, and thickness of the shielding material specimen was simulated from 0.1 ㎜ to 5 ㎜ by applying 15 × 15 ㎠ of specimen area, 4.5 g/㎤ of density of barium sulfate, and 11.34 g/㎤ density of lead. Entered source was simulated with 10kVp Step in consecutive X-ray energy spectrum(40 kVp ∼ 120 kVp). Absorption probability in 40 kVp ∼ 60 kVp showed same shielding rate with lead in 3 ㎜ ∼ 5 ㎜ of thickness, but it was identified that under 2 ㎜, the shielding rate was a bit lower than the existing lead shielding material. Also, the shielding rate in 70 kVp ∼ 120 kVp energy band showed similar performance as the existing lead shielding material, but it was tentatively estimated as fairly low shielding rate below 0.5 ㎜. This study estimated the shielding rate of barium compound as the thickness function of x-ray energy band for medical radiation through monte carlo simulation, and made comparative analysis with existing lead. Also, this study intended to verify application validity of the x-ray shielding material for medical radiation of pure barium sulfate. As a result, it was estimated that the shielding effect was 95% higher than the existing lead 1.5mm in at least 2mm thickness of barium compound in medical radiation energy band 70 kVp ∼ 120 kVp, and this result is considered valid to be provided as a base data in weight lightening production of radiation shielding product for medical radiation.