• Title/Summary/Keyword: Radiological Effects

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The Influence of the Change of Patient Radiation Exposure Dose Distribution on the Grid Condition and Detector Acquisition Dose on the Exposure Distance in the Use of Amorphous Silicon Thin Film Transistor Detector with AEC (자동노출제어장치를 이용한 비정질 실리콘 평판형 검출기에서 격자의 조건에 따른 환자선량 변화와 촬영 거리의 변화가 검출기 획득선량에 미치는 영향)

  • Yoon, Seok-Hwan;Choi, Jun-Gu;Han, Dong-Kyoon
    • Korean Journal of Digital Imaging in Medicine
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    • v.9 no.2
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    • pp.23-30
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    • 2007
  • This study attempts to propose an appropriate method of using digital medical imaging equipments, by studying the effects of automatic exposure control(AEC), grid ratio and the change of radiography distance on the patient dose and detertor acquisition dose during the procedure of acquiring image through a digital medical imaging detector. The change of dose following the change of grid ratio's exposure and radiography distance was measured, by using an abdominal phantom organized with tissue equivalent materials in an amorphous silicon thin film transistor detecter installed with AWC. The case to use grid ratio 12 : 1, focal distance 180cm to radiography distance 110cm in AEC, the patient dose increased rather when we used grid ration 10 : 1, focal distance 110cm. When AEC was not used,the dose necessary for image acquisition decreased as the grid ratio became higher and the distance became further. but detector acquisition dose was not reduced when in applied AEC. When purchasing digiral medical imaging equipments, optional items such as AEC and grid shall be accurately selected to satisfy the use of the equipments. Radiography error made by radiation technologist and unnenessary patient dose can be reduced by selecting equipments with a radiography distance marker equipment when it did not apply AEC. These equipments can also be helpful in maintaining high imaging quality, one of the merits of digital detectors.

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Effects of Ischemic Preconditioning of Different Intraoperative Ischemic Times of Vascularized Bone Graft Rabbit Models

  • Halim, Ahmad Sukari;Wan Ahmad Kamal, Wan Syazli Rodzaian;Noor, Norizal Mohd;Abdullah, Shafie
    • Archives of Plastic Surgery
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    • v.40 no.6
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    • pp.687-696
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    • 2013
  • Background Ischemic preconditioning has been shown to improve the outcomes of hypoxic tolerance of the heart, brain, lung, liver, jejunum, skin, and muscle tissues. However, to date, no report of ischemic preconditioning on vascularized bone grafts has been published. Methods Sixteen rabbits were divided into four groups with ischemic times of 2, 6, 14, and 18 hours. Half of the rabbits in each group underwent ischemic preconditioning. The osteomyocutaneous flaps consisted of the tibia bone, from which the overlying muscle and skin were raised. The technique of ischemic preconditioning involved applying a vascular clamp to the pedicle for 3 cycles of 10 minutes each. The rabbits then underwent serial plain radiography and computed tomography imaging on the first, second, fourth, and sixth postoperative weeks. Following this, all of the rabbits were sacrificed and histological examinations were performed. Results The results showed that for clinical analysis of the skin flaps and bone grafts, the preconditioned groups showed better survivability. In the plain radiographs, except for two non-preconditioned rabbits with intraoperative ischemic times of 6 hours, all began to show early callus formation at the fourth week. The computed tomography findings showed more callus formation in the preconditioned groups for all of the ischemic times except for the 18- hour group. The histological findings correlated with the radiological findings. There was no statistical significance in the difference between the two groups. Conclusions In conclusion, ischemic preconditioning improved the survivability of skin flaps and increased callus formation during the healing process of vascularized bone grafts.

Compression Angle of Ossification of the Posterior Longitudinal Ligament and Its Clinical Significance in Cervical Myelopathy

  • Lee, Nam;Yoon, Do Heum;Kim, Keung Nyun;Shin, Hyun Chul;Shin, Dong Ah;Ha, Yoon
    • Journal of Korean Neurosurgical Society
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    • v.59 no.5
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    • pp.471-477
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    • 2016
  • Objectives : The correction of clinical and radiologic abnormalities in patients with symptomatic ossification of the posterior longitudinal ligament (OPLL) is the current mainstay of treatment. This study aimed to identify radiographic predictors of severity of myelopathy in patients with symptomatic OPLL. Methods : Fifty patients with symptomatic cervical OPLL were enrolled. Based on Japanese Orthopedic Association (JOA) scores, patients were divided into either the mild myelopathy (n=31) or severe myelopathy (n=19) group. All subjects underwent preoperative plain cervical roentgenogram, computed tomography (CT), and MR imaging (MRI). Radiological parameters (C2-7 sagittal vertical axis, SVA; C2-7 Cobb angle; C2-7 range of motion, ROM; OPLL occupying ratio; and compression angle) were compared. Compression angle of OPLL was defined as the angle between the cranial and caudal surfaces of OPLL at the maximum level of cord compression Results : The occupying ratio of the spinal canal, C2-7 Cobb angle, C2-7 SVA, types of OPLL, and C2-7 ROM of the cervical spine were not statistically different between the two groups. However, the OPLL compression angle was significantly greater (p=0.003) in the severe myelopathy group than in the mild myelopathy group and was inversely correlated with JOA score (r=-0.533, p<0.01). Furthermore, multivariate regression analysis demonstrated that the compression angle (B=-0.069, p<0.001) was significantly associated with JOA scores (R=0.647, p<0.005). Conclusion : Higher compression angles of OPLL have deleterious effects on the spinal cord and decrease preoperative JOA scores.

Characteristics and Preparation of Gas Sensor Using Nano Indium Coated ZnO:In (나노 Indium을 부착한 ZnO:In 가스센서의 제작 및 특성)

  • Jung, Jong-Hun;Yu, Yun-Sik;Yu, Il
    • Korean Journal of Materials Research
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    • v.21 no.9
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    • pp.486-490
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    • 2011
  • Nano-indium-coated ZnO:In thick films were prepared by a hydrothermal method. ZnO:In gas sensors were fabricated by a screen printing method on alumina substrates. The gas sensing properties of the gas sensors were investigated for hydrocarbon gas. The effects of the indium concentration of the ZnO:In gas sensors on the structural and morphological properties were investigated by X-ray diffraction and scanning electron microscopy. XRD patterns revealed that the ZnO:In with wurtzite structure was grown with (1 0 0), (0 0 2), and (1 0 1) peaks. The quantity of In coating on the ZnO surface increased with increasing In concentration. The sensitivity of the ZnO:In sensors was measured for 5 ppm $CH_4$ gas and $CH_3CH_2CH_3$ gas at room temperature by comparing the resistance in air with that in target gases. The highest sensitivity to $CH_4$ gas and $CH_3CH_2CH_3$ gas of the ZnO:In sensors was observed at the In 6 wt%. The response and recovery times of the 6 wt% indiumcoated ZnO:In gas sensors were 19 s and 12 s, respectively.

The Efficacy and Safety of Beef Tallow Extract Including Cis-9-cetylmyristoleate in Patients with Osteoarthritis - As an Adjuvant Pharmacological Treatment -

  • Lee, Sang-Hoon;Kim, June-Hyuk;Cho, Whan-Seong;Seo, Sung-Wook;Kim, Sung-Kyu;Oh, Joo-Han
    • Preventive Nutrition and Food Science
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    • v.10 no.3
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    • pp.285-289
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    • 2005
  • In this double-blind, placebo-controlled trial, we assessed the efficacy and safety of beef tallow extract (BTE) including Cis-9-cetylmyristoleate in patients with arthritis. Between May and December 2003, we selected 80 patients (n=80) who showed/manifested arthritic symptoms and whose radiological findings were suggestive of arthritis, and randomly assigned them to placebo-controlled (n=40) and treatment group (n=40). The placebo (corn starch 350 mg) and BTE (208 mg) were orally administered to placebo-controlled and treatment group three times a day, respectively. We assessed the efficacy and safety based on the visual analogue scale (V AS) and modified knee society knee scores (MKSKS) at baseline and endpoint, respectively. To assess the safety, we monitored the adverse effects noted in liver, kidney, cardiovascular and gastrointestinal system for 3 weeks. Then, we performed not only a questionnaire study but also laboratory tests (e.g., liver function test, kidney function test, urinalysis, electrocardiography [EKG], complete blood cell counts [CBC] and chest X-ray). For statistical analysis, Student (-test and paired (-test were done using SPSS■ Version 11.0. Statistical significance was set at p < 0.05. The scores between V AS and MKSKS showed statistical significance (p < 0.05) with an improvement of $69.2\%$ (27/39) and $3.8\%$ (21/39) of treatment-group patients, respectively. Abnormal laboratory findings were noted in neither placebo-controlled nor treatment group. In conclusion, our results indicate that the administration of BTE was a safe and effective treatment regimen for patients with arthritis. In addition, the efficacy of BTE was more remarkable in alleviating the symptoms rather than improving the function.

Perception and Use of Complementary and Alternative Medicine in Diabetic Patients in Busan Area (보완대체요법에 대한 당뇨병환자의 인식 및 이용현황)

  • Kim, Hye-Ryung;Son, Eun-Joo;Kim, Mi-Kyung;Lyu, Eun-Soon
    • Korean Journal of Community Nutrition
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    • v.16 no.4
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    • pp.488-496
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    • 2011
  • The purpose of this study was to investigate the perception and utilization of Complementary and Alternative Medicine (CAM) for diabetic patients in Busan. The subjects were 227 patients at two general hospitals (over 400 bed). This study was performed through the interviewing process using questionnaires conducted from January to April, 2010. Of a total of subjects, 109 patients (48.0%) had taken CAM at least one time. The patients used CAM recognized that they were 'auxiliary medicines' (39.4%), 'supplementary health foods' (32.1%) and 'medicines' (19.3%), but inexperienced patients perceived them as 'supplementary health foods' (29.6%), 'unscientific treatment' (22.6%) and 'medicines' (20.2%), It was significantly different between two groups of patients (p < 0.001). The number of CAM types used for the patients was 51. The CAM types were plant foods (64.3%), dietary supplement (23.6%) and animal diets (12.1%). The patients used an average of 5.9 different kinds of CAM and an average of 3.8 years them and paid \93,345 per month. The patients with diabetic complications and for longer morbidity periods used CAM for significantly (p < 0.05) longer periods. The mean effectiveness scores of the patients used CAM were 3.31/5.00 for efficacy satisfaction, 3.58/5.00 for fewer side effects compared to those of oral drugs, 3.60/5.00 for psychological stability, 3.81/5.00 for easiness to use, and 3.06/5.00 for economic satisfaction. Of the patients that used CAM, 55.9% did not consult with doctors about CAM. More than two-thirds of the patients (77.1%) did not feel the need to consult with doctors.

A Study on the Planning of Civil Defense Shelter and Design 1 - On the ideas of the State of Civil Defense Shelter & Design Criteria - (민방위 대피시설 계획 및 설계 방안에 관한 연구 1 - 민방위 대피시설의 현황 및 설계기준을 중심으로 -)

  • Park, Namkwun;Paik, Sungkun
    • Journal of the Society of Disaster Information
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    • v.10 no.3
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    • pp.358-365
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    • 2014
  • North Korea has been preparing for WMD(Weapons Mass Destruction) using asymmetric force since it recognized the economic effects of CBR (Chemical, Biological, Radiological) weapons system operation and the limitations of conventional weapons. However, the threat only to conventional bombs, missiles and etc. is considered on the current Civil Defense Shelter, which could increase civil damages, not responding appropriately to disasters such as CBR weapons, terror attacks and etc. Therefore, this study confirms the current situation of Civil Defense Shelter and design criteria focused on CBR disasters so that we could make a plan and design of Civil Defense Shelter. In addition, we suggest the research result and improvements on Civil Defense Shelter and Design.

Intermediate-Term Clinical Outcomes after Total Ankle Arthroplasty for End-Stage Rheumatoid Arthritis with Modification of Perioperative Anti-Rheumatic Medication (말기 류마티스성 발목관절염에 대한 인공관절 전치환술 및 항류마티스 약물 조절 후의 중기 추시 임상 결과)

  • Cho, Byung-Ki;Ko, Ban-Suk
    • Journal of Korean Foot and Ankle Society
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    • v.23 no.3
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    • pp.91-99
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    • 2019
  • Purpose: This retrospective study reports the intermediate-term clinical outcomes including the practical function in daily and sports activities after total ankle arthroplasty for end-stage rheumatoid arthritis, as well as the effects of modification of perioperative anti-rheumatic medications. Materials and Methods: Twelve patients were followed for a minimum of 2 years after total ankle replacement for end-stage rheumatoid arthritis. Perioperative anti-rheumatic medications in all patients were modified based on a specific guideline. Clinical evaluations consisted of American Orthopaedic Foot and Ankle Society (AOFAS) scores, Foot and Ankle Outcome Score (FAOS), and Foot and Ankle Ability Measure (FAAM) scores. Periodic radiographic evaluation was conducted to detect changes in ankle alignment and postoperative complications. Results: Mean AOFAS, FAOS, and FAAM scores improved significantly from 37.5 to 81.2, 39.1 to 72.4, and 33.8 to 64.0 points at final follow-up, respectively (p<0.001). Functional outcomes in daily and sports activities at final follow-up were found to be 76.5 and 55.8 points for the FAOS and 70.5 and 57.5 points for the FAAM, respectively. As early postoperative complications, there was one case of local wound necrosis, one case of medial malleolar fracture, and one case of deep peroneal nerve injury. Radiological evaluation revealed two cases of asymptomatic heterotopic ossification and one case of progressive arthritis in the talonavicular joint. Reoperation was performed in only one patient (8.3%) with a medial soft tissue impingement at a mean of 35.6 months follow-up. Conclusion: Total ankle arthroplasty appears to be an effective surgical option for end-stage rheumatoid arthritis. Practical functions in daily and sports activities were significantly improved at intermediate-term follow-up. Modification of perioperative anti-rheumatic medications can be one of the solutions to reduce the postoperative complication rate.

Radiotherapy for gastric mucosa-associated lymphoid tissue lymphoma: dosimetric comparison and risk assessment of solid secondary cancer

  • Bae, Sun Hyun;Kim, Dong Wook;Kim, Mi-Sook;Shin, Myung-Hee;Park, Hee Chul;Lim, Do Hoon
    • Radiation Oncology Journal
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    • v.35 no.1
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    • pp.78-89
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    • 2017
  • Purpose: To determine the optimal radiotherapy technique for gastric mucosa-associated lymphoid tissue lymphoma (MALToma), we compared the dosimetric parameters and the risk of solid secondary cancer from scattered doses among anterior-posterior/ posterior-anterior parallel-opposed fields (AP/PA), anterior, posterior, right, and left lateral fields (4_field), 3-dimensional conformal radiotherapy (3D-CRT) using noncoplanar beams, and intensity-modulated radiotherapy composed of 7 coplanar beams (IMRT_co) and 7 coplanar and noncoplanar beams (IMRT_non). Materials and Methods: We retrospectively generated 5 planning techniques for 5 patients with gastric MALToma. Homogeneity index (HI), conformity index (CI), and mean doses of the kidney and liver were calculated from the dose-volume histograms. Applied the Biological Effects of Ionizing Radiation VII report to scattered doses, the lifetime attributable risk (LAR) was calculated to estimate the risk of solid secondary cancer. Results: The best value of CI was obtained with IMRT, although the HI varied among patients. The mean kidney dose was the highest with AP/PA, followed by 4_field, 3D-CRT, IMRT_co, and IMRT_non. On the other hand, the mean liver dose was the highest with 4_field and the lowest with AP/PA. Compared with 4_field, the LAR for 3D-CRT decreased except the lungs, and the LAR for IMRT_co and IMRT_non increased except the lungs. However, the absolute differences were much lower than <1%. Conclusion: Tailored RT techniques seem to be beneficial because it could achieve adjacent organ sparing with very small and clinically irrelevant increase of secondary solid cancer risk compared to the conventional techniques.

Safety Assessment on the Human Intrusion Scenarios of Near Surface Disposal Facility for Low and Very Low Level Radioactive Waste (저준위 및 극저준위 방사성폐기물 표층처분시설의 인간침입 시나리오 안전평가에 대한 고찰)

  • Hong, Sung-Wook;Park, Sangho;Park, Jin Beak
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.14 no.1
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    • pp.79-90
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    • 2016
  • The second-stage near surface disposal facility for low and very low level radioactive waste's permanent disposal is to be built. During the institutional control period, the inadvertent intrusion of the general public is limited. But after the institutional control period, the access to the general public is not restricted. Therefore human who has purpose of residence and resource exploration can intrude the disposal facility. In this case, radioactive effects to the intruder should be limited within regulatory dose limits. This study conducted the safety assessment of human intrusion on the second-stage surface disposal facility through drilling and post drilling scenario. Results of drilling and post drilling scenario were satisfied with regulatory dose limits. The result showed that post-drilling scenario was more significant than drilling scenario. According to the human intrusion time and behavior after the closure of the facility, dominant radionuclide contributing to the intruder was different. Sensitivity analyses on the parameters about the human behavior were also satisfied with regulatory dose limits. Especially, manual redistribution factor was the most sensitive parameter on exposure dose. A loading plan of spent filter waste and dry active waste was more effective than a loading plan of spent filter waste and other wastes for the radiological point of view. These results can be expected to provide both robustness and defense in depth for the development of safety case further.