• Title/Summary/Keyword: 단층선

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A Case of Mucocele in the Left Frontal Sinus (전두동 점액낭종)

  • 박병옥;노영식;소장영;김영길;김선우
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1981.05a
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    • pp.13.2-13
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    • 1981
  • Authors was experienced a case of mucocele in the left frontal sinus. A 24-years-old Korean male soldier was admitted to C.A.F.G.H. on 16th May 1980, with chief complaints of dull headache, exophthalmos, visual disturbance and intermittent epistaxis on the left side. On physical examination, left turbinates and septum were revealed hyperemic middle turbinate with blood tinged spots and deviated slightly to right side, and felt round, smooth, rubbery painless swelling within the orbit at the left inner canthus. The left orbital contents was displaced laterally producing proptosis with diplopia. On the radiological examination, Caldwell and Water's view showed hazy density in medial side of left orbital and left frontal sinus. Tomography of orbit showed hazy increased mass density with rather sharply defined outer margin of left bony orbit probably due to compressive erosion. The case was treated with surgical removal of the Lynch frontal approach, so present this case with a brief review of the literature.

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Effect of Gamma Rays Emitted by the 99mTc on the CT Image (99mTc에서 방출되는 감마선이 CT 영상에 미치는 영향)

  • Park, Jae-Yoon;Lee, Yong-Ki
    • Journal of the Korean Society of Radiology
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    • v.13 no.2
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    • pp.169-174
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    • 2019
  • This study examines the changes that $^{99m}Tc$ causes to CT(Computed Tomography) images quantitatively when CT scans were continuously performed using $^{99m}Tc$. With the use of the CT, $^{99m}Tc$ 740MBq was injected into the Resolution Phantom and Water Phantom, and the tube voltage was changed with 80 kVp and 120 kVp, scanning before and after the injection. The result indicate, by comparing the Signal Intensity according to the presence or absence of the $^{99m}Tc$ injection with the tube voltage of 120 kVp and 80 kVp, a decrease of 0.173 and 0.241 was observed respectively and the spatial resolution increase of 0.090 and 0.109 was observed respectively. The order of the test should be considered because the gamma rays of the radiopharmaceutical used in the nuclear medicine test do not affect the CT while the effective half-life of the radiopharmaceuticals should be considered for the CT scan to reduce the influence of the gamma rays emitted after the nuclear medicine test, with the possibility to reduce the difference of the results.

The Prediction of Ground Condition ahead of the Tunnel Face using 3-Dimensional Numerical Analysis (3차원 수치해석을 이용한 터널막장 전방 지반 상태의 예측)

  • You Kwang-Ho;Song Han-Chan;Kim Ki-Sun;Lee Dae-Hyuck;Park Yeon-Jun
    • Tunnel and Underground Space
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    • v.14 no.6 s.53
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    • pp.440-449
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    • 2004
  • Rock mass includes natural discontinuities such as joints and faults during its formation. Discontinuities are also referred as planes of weakness because of their weak mechanical characteristics. In the design of underground structures, it is necessary to consider the properties of discontinuities to insure the stability. During the excavation of a tunnel, these discontinuities have to be identified as early as possible so that proper change in excavation method or support design can be made accordingly. The excavation of the tunnel in a stable rock mass causes a 3-dimensional arching effect around the excavation face. It was revealed by previous studies that the existence of a weak zone or a fault zone ahead of tunnel foe induces a typical displacement tendency of convergence. For better understanding of the meaning of influence/trend lines of various displacement components, three-dimensional numerical analyses were conducted while varying deformation moduli, thicknesses and orientations of discontinuities. Numerical results showed that the changes in influence/trend lines of various displacement components were very similar to those by measurements. The discrepancies from the expected values were dependent on the physical properties, thicknesses and orientations of discontinuities.

Exposure Dose of Thyroid, Breast, and Sexual Gland using a Personal Dosimeter in Multiple CT Examinations (다중 CT 검사 시 개인선량계를 이용한 갑상선, 유방, 생식선의 피폭선량)

  • Kim, Hae-Suk;Kim, Jang-Oh;Lee, Yoon-Ji;Heo, Sung-Hoe;Lee, Chang-Ho;Min, Byung-In
    • Journal of the Korean Society of Radiology
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    • v.14 no.4
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    • pp.345-351
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    • 2020
  • In this study, a dose assessment was conducted on the exposure dose of thyroid, breast and sexual gland using a personal dosimeter in multiple CT examinations currently being conducted in health examinations. The dose assessment was measured by attaching TLD and EPD to the locations of the thyroid, breast and sexual gland during CT examinations of Brain, Brain + C-S, Brain + Low lung, Brain + L-S among CT items. The generated dose of equipment, CTDIvol and DLP, was measured. The study found that effective doses were rated 41.7% higher for thyroid TLD in Brain + C-S CT examinations than for the general public, 156% higher for EPD, 10% for breast EPD in Brain + Low Lung CT examinations, 124.4% higher for reproductive TLD and 339.8% higher for Brain + L-S CT examinations. The CTDIvol and DLP analysis results showed that C-S CTDIvol values were higher than the diagnostic reference levels at 0.6%, Low Lung CTDIvol values at 5.7%, DLP values at 11.8% and L-S CTDIvol values at 1.2%. In order to reduce the exposure dose of patients, indiscriminate examination is reduced and dose limit setting is needed in health examination.

3D Shape Reconstruction using the Focus Estimator Value from Multi-Focus Cell Images (다초점 세포 영상으로부터 추정된 초점 값을 이용한 3차원 형태 복원)

  • Choi, Yea-Jun;Lee, Dong-Woo;Kim, Myoung-Hee;Choi, Soo-Mi
    • Journal of the Korea Computer Graphics Society
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    • v.23 no.4
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    • pp.31-40
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    • 2017
  • As 3D cell culture has recently become possible, it has been able to observe a 3D shape of cell and volume. Generally, 3D information of a cell should be observed with a special microscope such as a confocal microscope or an electron microscope. However, a confocal microscope is more expensive than a conventional microscope and takes longer time to capture images. Therefore, there is a need for a method that can reconstruct the 3D shape of cells using a common microscope. In this paper, we propose a method of reconstructing 3D cells using the focus estimator value from multi-focal fluorescence images of cells. Initially, 3D cultured cells are captured with an optical microscope by changing the focus. Then the approximate position of the cells is assigned as ROI (Region Of Interest) using the circular Hough transform in the images. The MSBF (Modified Sliding Band Filter) is applied to the obtained ROI to extract the outlines of the cell clusters, and the focus estimator values are computed based on the extracted outlines. Using the computed focus estimator values and the numerical aperture (NA) of the microscope, we extract the outline of the cell cluster considering the depth and reconstruct the cells into 3D based on the extracted outline. The reconstruction results are examined by comparing with the combined in-focus portions of the cell images.

Reference line for computed tomogram of the mandible (하악골 전산화단층사진촬영시 기준선에 관한 연구)

  • You Choong-Hyun;Kim Jae-Duk
    • Imaging Science in Dentistry
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    • v.32 no.3
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    • pp.153-157
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    • 2002
  • Purpose : This study was performed to determine the proper reference line for taking axial computed tomograms from which the good cross-sectional views can be reformatted by multiplanar reconstruction. Methods : Three dry mandibles with implanted gutta percha cones in the extracted socket were scanned axially according to 6 reference lines of 2 mandibular positions with computed tomogram Hitachi W550. The accuracy of measurements of the lengths of implanted gutta perch a cones in the each cross-sectional view reformatted from axial computed tomogram by multiplanar reconstruction was evaluated. Results: The difference between the measurements and the real length of implant was smallest in the bucco-lingual views reformatted from the axial views scanned according to the reference line of group V-a. The smaller the angle difference between reference line and occlusal line was, the smaller the difference between the measurements in the bucco-lingual views reformatted from axial views and the real length of implant. The majority of measured widths of implants in the bucco-lingually reformatted views were larger than the actual values. Conclusions : When the mandible is inclined within the limitation of gantry angle and scanned with the reference line coincident with occlusal plane, the bucco-lingual view can be reformatted without deformation of images from the axially scanned images.

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Quantitative Evaluation of CT Artifact Elimination with various Cut-off Frequency of Hann Filter (Hann 필터의 Cut-off 주파수 변화에 따른 CT 영상의 Artifact 제거효과에 대한 정량적 평가)

  • Kang, Bo-Sun
    • Journal of the Korean Society of Radiology
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    • v.2 no.3
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    • pp.5-9
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    • 2008
  • In the computerized tomography(CT), various filters are using in the reconstruction algorithm to reduce or eliminate the artifacts which are intrinsically induced by the imperfection of mathematical methods for reconstruction, lack of real informations about anatomic structures in the projection image, errors in data acquisition and so on. Hann filter was used to evaluate the filter effects on the elimination of reconstruction artifact in the CT image. The quantitative study was done by changing cut-off frequency of Hann filter from 0.1 to 0.9 with frequency increasement by 0.2. NPS analysis was fulfilled for the quantitative evaluation of filter effect.

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A Case of Dizziness Patient diagnosed as Cerebellar infarction and treated with Qingyanligetang(淸咽利膈湯) (소뇌경색(小腦梗塞)으로 인한 중추성(中樞性) 현운환자(眩暈患者)의 치험(治驗) 1례(例))

  • Han, Gi-Sun;Lee, Won-Chul
    • The Journal of Dong Guk Oriental Medicine
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    • v.9
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    • pp.25-33
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    • 2000
  • Dizziness is one of the common symptoms in many patients. The disorders of the labyrinth, vestibular nerve, vestibular neclei, or their central connections are responsible for practically all vertigo. Most disorders of the central connections are the vascular diseases and tumors. This study is based on the clinical consideration of one patient who sufferd from the cerebellar infarction and the upper respiratory infection. The patient, 61 - year - old man was diagnosed as the cerebellar infarction has been troubled with dizziness, a headache, a sore throat, a cough etc. The symptoms are classed as the Sanchopungyeul.(上焦風熱) Pungdam(風痰), and we prescribed Qingyanligetang(淸咽利膈湯) for him and his symptoms took a tum for the better.

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Diagnostic Value of Computed Tomography in Acetabular Fracture (관골구 골절에서의 전산화단층촬영술의 진단적 가치)

  • Kim, Sun-Yong;Park, Bok-Hwan;Ihn, Joo-Chul
    • Journal of Yeungnam Medical Science
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    • v.5 no.1
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    • pp.43-48
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    • 1988
  • We retrospectively analysed 22 patients pelvic CT, in whom the acetabular fracture were suspected in plain film. And compared and analysed the computed tomogram findings and plain radiographic findings. The results were as follows. CT enables better evaluation of shape, extent, and degree of separation of fragment. CT was helpful in detecting the combinded fracture and soft tissue injuries. CT showed intraarticular loose bodies, which were invisible on plain film. In patients with pelvic trauma, no necessary changing position during CT examination. CT was useful demonstrates the remnant of intraarticular osseous fragment and adequacy of reduction after surgery.

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A Case of Pulmonary Lymphangioleiomyomatosis Developed in Tuberous Sclerosis with Renal Angiomyolipoma (신혈관근지방종을 동반한 결절성 경화증에서 발생한 폐림프관평활근종증 1예)

  • Kim, Myung-Im;Kang, Hong-Mo;Lee, Ho-Jong;Koh, Yong-Ho;Cho, Yong-Seon;Yoo, Jee-Hong
    • Tuberculosis and Respiratory Diseases
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    • v.48 no.5
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    • pp.788-793
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    • 2000
  • Tuberous sclerosis is a rare hereditary anomaly of variable penetrance characterized by mental retardation, epilepsy, and adenoma sebaceum. Pulmonary involvement is uncommon, but, when involved by tuberous sclerosis, it shows characteristic reticulonodular infiltration and cystic changes. Lymphangioleiomyomatosis is a rare disease of unknown cause that affects women of reproductive age. It is characterized by progressive proliferation of smooth muscle in the lung. We experienced one case of pulmonary lymphangioleiomyomatosis associated with tuberous sclerosis in a 26-year-old female patient. This case is reported with a brief review of the literature.

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