• Korean Journal of Radiology
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• 제22권9호
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• pp.1441-1450
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• 2021

Anomalous origin of the coronary artery from the pulmonary artery is a rare and potentially fatal congenital heart defect. Up to 90% of infants with an anomaly involving the left coronary artery die within the first year of life if left untreated. Patients who survive beyond infancy are at risk of sudden cardiac death. Cardiac CT and MRI are increasingly being used for the accurate diagnosis of this anomaly for prompt surgical restoration of the dual coronary artery system. Moreover, life-long imaging surveillance after surgery is necessary for these patients. In this pictorial review, multimodal cardiac imaging findings of this rare and potentially fatal coronary artery anomaly are comprehensively discussed, and representative images are provided to facilitate the understanding of this anomaly.

• Journal of the Korean Physical Society
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• 제73권11호
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• pp.1644-1649
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• 2018

Aiming at infrared thermal images with different buried depth defects, we study a variety of image segmentation algorithms based on the threshold to develop global search ability and the ability to find the defect area accurately. Firstly, the iterative thresholding method, the maximum entropy method, the minimum error method, the Ostu method and the minimum skewness method are applied to image segmentation of the same infrared thermal image. The study shows that the maximum entropy method and the minimum error method have strong global search capability and can simultaneously extract defects at different depths. However none of these five methods can accurately calculate the defect area at different depths. In order to solve this problem, we put forward a strategy of "divide and conquer". The infrared thermal image is divided into several local thermal maps, with each map containing only one defect, and the defect area is calculated after local image processing of the different buried defects one by one. The results show that, under the "divide and conquer" strategy, the iterative threshold method and the Ostu method have the advantage of high precision and can accurately extract the area of different defects at different depths, with an error of less than 5%.

• Investigative Magnetic Resonance Imaging
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• 제7권2호
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• pp.116-123
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• 2003

목적 : 가토 모델을 이용한 급성 허혈성 뇌경색에서 확산강조 자기공명영상과 관류자기공명영상의 유용성에 대해 알아보고자 하였다. 대상 및 방법 : 여섯 마리의 순계 가토의 경동맥에 히스토아크릴글루와 리피오돌 및 텅스텐 파우더를 동맥내 주입하여 뇌경색을 유발한 후 1시간 내에 고식적인 T1 및 T2 강조영상, 그리고 확산강조 자기공명영상과 관류자기공명영상을 획득하였다. 관류자기공명영상은 측내실 수준과 대뇌기저핵의 1cm 상방에서 각각 얻었고, 이 영상을 특수 영상 소프트웨어로 후처리하여 뇌혈류 용적 , 뇌혈류양 및 평균 조영제 통과시간을 포함한 관류 영상을 획득하였다. 뇌경색 부위는 각각의 관류 지도와 확산강조 자기공명영상으로 평가하였다. 뇌경색 부위와 반대편 정상 부위에서 조영제 평균 통과시간 차이를 측정하였다. 결과 : 모든 가토에서 T2 강조영상상 비정상 신호강도는 없었으나 확산강조 자기공명영상에서 고신호강도의 뇌경색 병변을 확인할 수 있었다. 상대적 뇌혈류용적, 뇌혈류양 및 평균 조영제 통과시간을 포함한 관류자기공명영상에서 모두 관류 결손을 인지할 수 있었다. 뇌혈류양과 평균 조영제 통과시간 지도에서 관류결손지역으로 나타난 면적의 비교는 6예 중 4예에서 평균 조영제 통과시간 지도가 뇌혈류양 지도보다 면적이 크게 나왔으며, 2예는 같았다. 평균 조영제 통과시간 지도의 관류결손 면적이 뇌혈류양 지도보다 작게 나온 경우는 없었다. 또한 뇌혈류양 지도에서 병변의 면적은 확산강조 자기공명영상에서의 병변의 면적보다 3예에서 넓게 나타났고, 3예에서 같게 나타났다. 평균 조영제 통과시간 지도에서 병변의 면적은 확산강조 자기공명영상에서의 병변의 면적보다 모두 크게 나타났다. 평균 조영제 통과시간 지도에서 병변의 면적이 뇌혈류양 지도에서 병변의 면적보다 크면서 확산강조 자기공명영상에서와 같은 경우가 3예, 뇌혈류양 지도에서 병변의 면적이 확산강조 자기공명영상에서와 같으며 평균 조영제 통과시간 지도에서 병변의 면적보다 작은 경우가 3예, 그리고 평균 조영제 통과시간 지도에서 병변의 면적이 뇌혈류양 지도의 병변의 면적보다 크면서 확산강조 자기공명영상에서의 면적이 가장 적은 경우가 1예 있었다. 결론 : 확산강조 자기공명영상과 관류자기공명영상은 가토에서 초급성 뇌경색을 진단하고 뇌혈류 역학상태를 평가하는데 유용한 기법이라고 생각된다.

• Nuclear Medicine and Molecular Imaging
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• 제43권2호
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• pp.156-158
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• 2009

• Journal of Cardiovascular Imaging
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• 제26권4호
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• pp.256-257
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• 2018

• Journal of Korean Neurosurgical Society
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• 제64권2호
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• pp.238-246
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• 2021

Objective : To retrospectively analyze the clinical characteristics and surgical experience of 10 adults with spinal extradural meningeal cysts (SEMCs) in the thoracolumbar spine which may further provide evidence for surgical decision-making. Methods : Ten adults with SEMCs in the thoracolumbar spine were surgically treated and enrolled in this study. Clinical manifestations, imaging data, intraoperative findings and postoperative outcome were recorded. Results : Clinical manifestations of SEMCs included motor and sensory dysfunction of the lower limbs and urination and defecation disturbance. The cysts presented as intraspinal occupying lesions dorsal to the spine, ranging from the T8 to L3 level. Defects of eight cases were found on preoperative magnetic resonance imaging (MRI). Selective hemilaminectomy or laminectomy were used to reveal the defect within the cyst, which was further sutured with microscopic technique. The final outcome was excellent or good in seven cases and fair in three cases. No recurrence was observed during follow-up. Conclusion : SEMCs are rare intraspinal cystic lesions. Radiography and MRI are clinically practical methods to assess defects within SEMCs. Selective hemilaminectomy or laminectomy may reduce surgical trauma. Detection and microscopic suturing of the defects are the key steps to adequately decompress the nervous tissue and prevent postoperative recurrence.

• Journal of Korean Neurosurgical Society
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• 제46권6호
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• pp.522-527
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• 2009

Objective : Atlantal arch defects are rare. Few cadaveric and imaging studies have been reported on the variations of such anomalies. Our goal in this study was to examine the incidence and review the clinical implications of this anomaly. Methods : A retrospective review of 1,153 neck or cervical spine computed tomography (CT) scans was performed to identify patients with atlantal arch defects. Neck CT scans were performed in 650 patients and cervical spine CT scans were performed in 503 patients. Posterior arch defects of the atlas were grouped in accordance with the classification of Currarino et al. In patients exhibiting this anomaly, special attention was given to defining associated anomalies and neurological findings. Results : Atlantal arch defects were found in 11 (11/1153, 0.95%) of the 1,153 patients. The type A posterior arch defect was found in nine patients and the type B posterior arch defect was found in two patients. No type C, D, or E defects were observed. One patient with a type A posterior arch defect had an anterior atlantal-arch midline cleft (1/1153, 0.087%). Associated cervical spine anomalies observed included one $C_{6-7}$ fusion and two atlantal assimilations. None of the reviewed patients had neurological deficits because of atlantal arch anomalies. Conclusion : Most congenital anomalies of the atlantal arch are found incidentally during investigation of neck mass, neck pain, radiculopathy, and after trauma.

• 대한두개안면성형외과학회지
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• 제21권1호
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• pp.69-72
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• 2020

Hemangioma is a benign vascular tumor that grows by endothelial cell hyperplasia. It occurs most frequently in the head and neck region. Nose reconstruction is tricky because of its unique three-dimensional structure and different tissue components. We report a case of successful reconstruction of near-total nose defect using the paramedian forehead flap combined with a nasolabial flap, immediately after excision of nasal hemangioma. A 49-year-old male patient was presented with a huge mass at the nose. Preoperative magnetic resonance imaging showed prominent vascular channels extending to the forehead and cheek. Complete resection of the mass was performed, which resulted in an eccentric defect. The right paramedian forehead flap and the left nasolabial flap were designed and transferred to the defect. Flap division was performed 1 month later. The patient is satisfied with the overall appearance and did not develop any functional deficit.

• Imaging Science in Dentistry
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• 제36권2호
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• pp.81-88
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• 2006

Purpose : To review developmental salivary gland defect based on 12 reported cases and literature, and to guide radiographic diagnosis of this entity. Materials and Methods : The 12 cases of developmental salivary gland defect of Chosun University Dental Hospital in the last 4 years were analyzed and compared with previous reported cases. Result : 11 of the 12 cases were found in men, indicating a very strong male predilection. The peak age was in the 6th decade. These defects were situated just above or at the inferior border of mandible between the first molar and the mandibular angle, and always Inferior to the mandibular canal. Only one case was superimposed with the mandibular canal, 6 cases were superimposed with the inferior border of the mandible. Conclusion : Characteristically, these defects had a special radiographic features such as ovoid shaped well-defined radiolucency located just above or at the inferior border of the mandible between the first molar and the mandibular angle, and always inferior to the mandibular canal. The recognition of these radiographic features were diagnostically valuable.

• Imaging Science in Dentistry
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• 제46권2호
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• pp.141-144
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• 2016

The aim of this report is to present two cases of canalis basilaris medianus as identified on cone-beam computed tomography (CBCT) in the base of the skull. The CBCT data sets were sent for radiographic consultation. In both cases, multi-planar views revealed an osseous defect in the base of the skull in the clivus region, the sagittal view showed a unilateral, well-defined, non-corticated, track-like low-attenuation osseous defect in the clivus. The appearance of the defect was highly reminiscent of a fracture of the clivus. The borders of osseous defect were smooth, and no other radiographic signs suggestive of osteolytic destructive processes were noted. Based on the overall radiographic examination, a radiographic impression of canalis basilaris medianus was made. Canalis basilaris medianus is a rare anatomical variant and is generally observed on the clivus. Due to its potential association with meningitis, it should be recognized and reported to avoid potential complications.