• Journal of radiological science and technology
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• v.28 no.2
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• pp.111-115
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• 2005

The quality of image from the system that creates medical images by using X-ray depends on the various different reasons such as the X-ray generator, the subject and the image transmission medium. In other words, thereare various factors existing that can influence on the quality of image from the moment when the X-ray is generated and until the final image is created. Therefore, the operator who creates images at the clinical site should make continuous evaluation and observation from the final image. There are various methods of evaluating the medical images, but it is assumed that the MTF measurement method can be suitable for measuring actual or effective resolution. So in this study, the MTF measurement method by using X-ray film has been avoided and the MTF features according to the deterioration of the X-ray system have been measured by using the software (the program used Borland C++ builder software and LEAD tools software) that can measure the MTF of the digital medical images. As the result of this measurement, it has been found out through the MTF graph that the resolution and sharpness from the old x-ray generator with a many years of using and many numbers of times of using were deteriorated for the quality of image comparing to those from the new system. Also a simple and easy measurement method for the MTF from the digital medical images can be obtained in this study.

• Journal of the Korean Society of Radiology
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• v.13 no.1
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• pp.31-37
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• 2019

The study analyzes Non SEMAC and SEMAC to reduce susceptibility artifacts that may occur when performing magnetic resonance imaging(MRI) of metal patients. The Foot and Ankle Phantom was used as the experimental tool and the 3.8 cm general screw was used to make the magnetic susceptibility artifact. The experimental equipment was used 3.0T Magnetom Skyra and the area was measured with the 17th image where the signal off is the most noticeable in the obtained image. Statistical analysis was performed using the SPSS(Ver.25) program and the significance was assessed by the Wilcoxon Signed Rank Test. As a result, the area of Non SEMAC which is the lowest signal was $289.53{\pm}23.07197mm$. When the Turbo Factor was changed to 3, 4, and 5 after SEMAC use, it decreased to $125.02{\pm}7.45875mm$, $120.96{\pm}12.01704mm$ and $108.79{\pm}16.53498mm$, respectively. In conclusion, this study demonstrates that Using SEMAC with Turbo Factor effectively reduces the susceptibility artifacts.

• The Journal of the Korea Contents Association
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• v.19 no.6
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• pp.471-480
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• 2019

L-spine 3~4, L-spine 4~5, and L-spine 5~Sacrum 1 intervertebral disc(IVD) angle according to gender, age, body mass index(BMI), lumbar lordosis angle(LLA) were compared and analyzed. The anteriorposterior incidence angle of L-spine 3 ~ 4, L-spine 4 ~ 5 and L-spine 5~Sacrum 1 in body mass index were 5.66, 13.23 and 29.13 degrees in the head direction and L-spine 3 4, L-spine 4 ~ 5, L-spine 5~Sacrum 1 had 6.32 degrees, 16.09 degrees and 35.36 degrees in the head direction. The distortion area ratio comparison was performed with the phantom image using the proposed incidence angle. There was a significant difference in L-spine 4~5 and L-spine 5~Sacrum 1 IVD angle relative to body mass index and LLA(p<0.05), IVD angle and LLA were positively correlated(p<0.05).As a result of evaluating the usefulness of the image by applying the incidence angles of the disc angles according to the phantom angle of deviation to the head direction as 11 degrees for L4 and 26 degrees for L5, the distortion ratio area decreased from 14.90% to 12.11% in L4, And from 15.25% to 13.72% in L5. In anteriorposterior image of the Lumbar spine applying the incidence angle according to the measured disc angle, it is possible to reduce the distortion to purpose L4, L5. And improved the quality and diagnostic information of the target site.

• Journal of radiological science and technology
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• v.31 no.2
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• pp.115-121
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• 2008

Purpose: Aortic Dissection is very dangerous, prognostic disease, which the bloodstream flow out of the true lumen of the aorta by the bursting of aortic intima resulting in a rapid dissociation of inner and outer layer from the media. It is difficult to diagnose aortic dissection clinically by normal X-ray. This study was to investigate the occurrence frequency by age and number of patients who are identified to be aortic dissection by CT (Computed Tomography) scan. Materials and methods: We investigated the trend of yearly fluctuation, gender, age, and department of clinical research of the 112 patients who conducted CT scan in C- University Hospital for two years from January 2005 to December 2006. The MIP and SSD which reconstructed CT image and the VRT image were obtained for the accurate observation. The result was investigated by comparing normal X-ray and CT scan. Results and Conclusion: 1. The yearly check of 112 patients conducted CT scan showed 37 people (41.9%) in 2005, and it was increased to 65 (58.1%) in 2006 by 1.4 times. 2. The gender distribution of patients given a CT scan showed 45 males (40.1%), and female 67 (59.9 %). The aortic dissection patients were 9 (20%) out of 45 males, 21 (31.3%) out of 67 females and women were 1.6 times more than men. Women are also 1.5 times more than men in the number of examinee. 3. The age distribution of patient's who conducted CT scan revealed that there was no patient under 30 years old while 88.3% of all patients were through 41 to 80 years old. The higher the age was, the higher the occurrence of aortic dissection was. The difference in the occurrence frequency of age was statistically significant (p<0.01). 4. The departments that requested CT scan were the emergency department 46 (41.1%), circulatory internal medicine 37 (33.0%), chest surgery 13 (11.6%), and others 6 (14.3%). The combined ratio of emergency medicine and circulatory internal medicine was 74.1% of all. The results show that the aortic dissection is a very dangerous disease whose patients visit mainly via the emergency room. 5. The aortic dissection patients had normal X-ray readings in 22 (73.3%) out of 30, and only 8 (26.7 percent) are abnormal in the X-ray diagnosis. Therefore, the CT scan needs to be enforced in order to assess accurately the disease of aortic dissection.

• Journal of Veterinary Clinics
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• v.28 no.6
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• pp.613-616
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• 2011

A 5-year-old male German shepherd dog was presented with a 4 day-history of anorexia and depression. Abdominal radiographs showed a large soft tissue mass and loss of serosal detail. Ultrasonographs revealed splenomegaly with the lacy pattern parenchyma, perivenous hyperechoic region at the splenic hilum, and loss of splenic venous flow. Computed tomographic findings included the enlarged non-enhanced spleen except perivenous region at the splenic hilum and a whirled soft tissue mass at the splenic hilum. Exploratory laparotomy confirmed the diagnosis of splenic torsion. Ultrasonographic findings including lacy appearance, hyperechoic perivenous echogenicity and absence of splenic blood flow and CT findings including no or minimal enhancement of the spleen and a whirled appearance of splenic pedicle could be useful for diagnosing isolated splenic torsion in the dog.

• Archives of Craniofacial Surgery
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• v.11 no.1
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• pp.23-27
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• 2010

목적: 모반양 기저세포암 증후군 (Nevoid basal cell carcinoma syndrome) 또는 골린-골츠 증후군은 한국에서는 흔하지 않은 증후군으로 주로 상염색체 우성으로 유전하고 다기관 장애가 나타날 수 있으며 높은 표현율과 다양한 표현도를 특징으로 한다. 모반양 기저세포암 증후군의 진단 기준에는 다발성 기저세포암, 이소성 석회화(ectopic calcification), 손 또는 발바닥 오목 (palma or plantar pits), 치성 각화 낭종(odontogenic keratocysts), 가족력 및 골격계, 신경계, 안, 비뇨생식계 및 심장혈관의 이상 등이 있다. 본원에서 주로 두부의 다발성 기저세포암을 가진 모반양 기저세포암 증후군 환자를 경험하여 보고하고자 한다. 방법: 환자는 2007년 4월 두부의 색소성 모반으로 피부과에서 시행한 펀치 생검에서 기저세포암을 진단받고 의뢰되었으며, 이후 2009년 7월까지 14회의 추가적인 절제 및 조직 검사를 시행하였다. 환자는 갑상샘 유두암종의 재발로 인해 갑상샘 절제술을 2회 시행한 과거력이 있었으며 이학적 검사와 일반 혈액, 소변, 간 기능 및 갑상선 기능 검사를 시행하였고, 흉부와 늑골 방사선 검사, 심전도와 안면부 및 두부 컴퓨터단층촬영과 유전자 검사를 시행하였다. 결과: 두부와 안면부에서 절제한 27개의 병변 중 23개(85%)가 기저세포암으로 진단되었으며, 치성 각화 낭종과 대뇌겸 석회화, 이학적 검사에서 손바닥 오목이 발견되었다. 하복부 초음파에서 난소 낭종이 발견되었으나 조직 검사는 시행되지 않았다. 결론: 한국에서 모반양 기저세포암 증후군에 대한 연구는 주로 치과와 피부과 영역에서 국한되었으며, 특히 치과 영역에서의 보고는 치성 각화 낭종 및 손바닥 오목에 초점을 둔 것이 대부분이었다. 이에 본원에서는 주로 두부의 다발성 기저세포암을 가진 모반양 기저세포암의 환자를 경험하였으며, 초기에 발견된 작은 병변의 제거 시 2mm의 정상 조직을 포함하여 절제하였어도 3년간의 경과관찰 중 재발없이 좋은 결과를 얻을 수 있어 이를 보고하는 바이다.

• Clinics in Shoulder and Elbow
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• v.10 no.1
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• pp.124-130
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• 2007

The acromioclavicular separation (AC separation) is a common injury, which is often accompanied by the rupture of the coracoclavicular ligament (CC ligament) in severe occasions. In rare forms of AC separation, the fracture of the coracoid process would occur rather than the rupture of the CC ligament. Only 31 cases of such injury have been reported in the English literature. We present 2 additional cases with literature review. The fracture of the coracoid process is not readily seen on anteroposterior shoulder radiograms. Severe AC separation without widening of CC distance on anteroposterior shoulder radiogram heralds the fracture of the coracoid process.

• Journal of Veterinary Clinics
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• v.26 no.6
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• pp.628-631
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• 2009

Five dogs presented to the Veterinary Medical Teaching Hospital of the Konkuk University and Hangang Animal Hospital with a history of foreign body ingestion. On physical examination, five dogs showed lethargy, anorexia, or vomiting. Plain radiographs revealed that radiopaque foreign bodies lodged in the heart base or caudal thoracic esophagus. Positive contrast esophagogram revealed that large foreign bodies severely expanded the esophagus and there was no evidence of leakage of the contrast agent from the esophagus into the thoracic cavity. Gastrotomy for retrieval of esophageal foreign bodies using long forceps technique was performed. Esophageal foreign bodies were successfully retrieved in all dogs. The follow-ups were completed 10 days to 2 years after surgery. The follow-up information was based on physical examination by veterinarians and telephone interview with owners. The owners reported that there was no evidence of complications related to surgery such as vomiting, regurgitation, dysphagia, gagging, hyper-salivation, or anorexia in all dogs.

• Journal of Chest Surgery
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• v.40 no.1 s.270
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• pp.52-55
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• 2007

Unilateral pulmonary artery agenesis is a rare congenital malformation usually associated with other cardiovascular anomaly such as Tetralogy of Fallot. Isolated pulmonary artery agenesis is very rare, and usually asymptomatic. It is usually highly suspected by routine chest X-ray, and associated symptoms are hemoptysis, blood tinged sputum, repeated pulmonary infection, and dyspnea on exertion. We have recently experienced the right pulmonary artery agenesis in 27 year-old male patient, complaining of minimal hemoptysis and sustained blood tinged sputum. He was successfully treated by right pneumonectomy, so we report this case with the review of associated literature.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.118-118
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• 2013

DMM은 방사광가속기의 백색광으로부터 단색광을 추출하기 위해 두 개의 다층 박막 (multilayer) 거울을 사용하는데, 첫 번째 거울은 Bragg 반사를 통해 분광을 하여 단색광을 생산하는 용도이고, 두 번째 거울은 이 단색광을 반사시켜 지면과 평행하게 출사되게 하기 위함이다. 일반적으로 사용되는 DCM (Double Crystal Monochromator)과의 차이점은, Bragg 반사를 위해 DCM에서는 결정을 사용하는 반면 DMM은 밀도차이가 많이나는 두 종류의 물질을 교대로 쌓아 올린 다층 박막을 사용한다는 것이다. 다층 박막의 주기가 곧 Bragg 반사에서의 d-spacing이 되며, X-선 분광의 목적으로 사용되는 d-spacing은 10-50 $\AA$ 사이이다. DCM이 0.01% 대의 우수한 에너지 분해능을 보이는데 비해, DMM은 1% 정도이다. 이 때문에 출사광의 밝기가 DCM에 비해 100배 밝은 특징이 있어서 에너지 분해능보다 광량이 더 중요한 응용에서 DMM이 사용된다. X-선 영상이나 방사선치료가 바로 이러한 응용에 해당한다. DMM은 포항가속기연구소와 (주) 벡트론에서 공동 설계하였으며, (주)벡트론에서 제작하였다. 그림 1에 DMM의 외형과 내부 구조를 나타내었다. Bragg 각의 조절 범위는 0.24-0.9도 이다. 입사광과 출사광의 수직 방향 offset을 10 mm로 유지하기 위해 두 번째 다층 박막이 수평방향으로 1,000 mm 가량 이동할 수 있어야 한다. 이를 위해 두 대의 고니오미터 stage를 사용하여 각각 첫 번째 및 두 번째 다층 박막의 위치와 방향을 제어한다. 첫 번째 다층 박막을 제어하는 고니오미터 stage는 하부가 전체 프레임에 고정되어 있고, 이 고니오미터의 회전축에서 Bragg 각을 조절한다. 두 번째 다층 박막을 제어하는 고니오미터 stage는 높이방향과 수평방향으로 이동이 가능하다. 다층 박막의 pitch는 고니오미터의 회전축에서 조절한다. 그리고 tilt stage를 사용하여 다층 박막의 roll을 조절한다.