• Title/Summary/Keyword: Computerized Tomography

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The Use of Pedicle Screw-Rod System for the Posterior Fixation in Cervico-Thoracic Junction

  • Cho, Won-ik;Eid, Ahmed Shawky;Chang, Ung-Kyu
    • Journal of Korean Neurosurgical Society
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    • 제48권1호
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    • pp.46-52
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    • 2010
  • Objective : In cervico-thoracic junction (CTJ), the use of strong fixation device such as pedicle screw-rod system is often required. Purpose of this study is to analyze the anatomical features of C7 and T1 pedicles related to screw insertion and to evaluate the safety of pedicle screw insertion at these levels. Methods : Nineteen patients underwent posterior CTJ fixation with C7 and/or T1 included in fixation levels. Seventeen patients had tumorous conditions and two with post-laminectomy kyphosis. The anatomical features were analyzed for C7 and T1 pedicles in 19 patients using computerized tomography (CT). Pedicle screw and rod fixation system was used in 16 patients. Pedicle violation by screws was evaluated with postoperative CT scan. Results : The mean values of the width, height, stable depth, safety angle, transverse angle, and sagittal angle of C7 pedicles were $6.9{\pm}1.34\;mm$, $8.23{\pm}1.18\;mm$, $30.93{\pm}4.65\;mm$, $26.42{\pm}7.91$ degrees, $25.9{\pm}4.83$ degrees, and $10.6{\pm}3.39$ degrees. At T1 pedicles, anatomic parameters were similar to those of C7. The pedicle violation revealed that 64.1% showed grade I violation and 35.9% showed grade II violation, overall. As for C7 pedicle screw insertion, grade I was 61.5% and grade II 38.5%. At T1 level, grade I was 65.0% and grade II 35.0%. There was no significant difference in violation rate between the whole group, C7, and T1 group. Conclusion : C7 pedicles can withstand pedicle screw insertion. C7 pedicle and T1 pedicle are anatomically very similar. With the use of adequate fluoroscopic oblique view, pedicle screw can be safely inserted at C7 and T1 levels.

하악 관절와의 형태가 하악 이부편위에 미치는 영향에 관한 3차원 영상 연구 (3-D CT Image Study of Effect of Glenoid Fossa on Menton Deviation)

  • 조진형;이경민;박홍주;황현식
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제33권4호
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    • pp.337-345
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    • 2011
  • Purpose: The purpose of this study was to define the relation of the degree of menton deviation and 3-D CT (computerized tomography) measurements of the glenoid fossa and the mandible, which are considered to have an influence on menton deviation. Methods: The CT images were obtained in 60 adults and these were transmitted to a computer and reconstructed using computer software. According to the degree of the menton deviation, which was measured on the posteroanterior cephalogram, the subjects were divided into the menton deviated group (30 adults) and the symmetry group (30 adults). A total of 11 measurements that might have an effect on menton deviation were determined and these were measured in the right and left sides using the function of 3-D measurement in the computer program. The 11 measurements consist of 6 measurements in the glenoid fossa (vertical position of the glenoid fossa and articular eminence, the sagittal position of the glenoid fossa and articular eminence, the depth of the glenoid fossa, and the anterior angle of the glenoid fossa), and 5 measurements in the mandible (ramus length, frontal ramal inclination, lateral ramal inclination, body length, body height). Results: The comparison of the differences between the menton deviated and symmetry groups and correlation analysis on the degree of menton deviation were carried out. The results of comparison of the right and the left difference between the menton deviated and symmetry groups showed that the vertical position and depth of the glenoid fossa were significantly increased in the menton deviated group. Conclusion: The results of the present study show that consideration of the shape and position of the glenoid fossa is necessary for making the diagnosis and administering proper treatment in facial asymmetry patients and especially growing patients.

가토 두개골 결손부 모델에서 테트라사이클린 함유 실크 파이브로인 차폐막의 골유도 재생 효과 (The Effects of Tetracycline-loaded Silk Fibroin Membrane on Guided Bone Regeneration in a Rabbit Calvarial Defect Model)

  • 이상운;박용태;김성곤;권해용;조유영;이희삼
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제34권5호
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    • pp.293-298
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    • 2012
  • Purpose: The aim of this study was to evaluate the bone regeneration ability of 1% tetracycline (TC)-loaded silk fibroin membrane (SFM), in a rabbit calvarial defect model. Methods: Twenty New Zealand white rabbits were used for this study. Bilateral round defects were made on the rabbit parietal bone, using trephine bur with an 8 mm diameter. TC-loaded SFM or SFM was covered on the right parietal bone defect, and the left parietal bone defects were uncovered for the control. The animals were humanely sacrificed at 4 or 8 weeks postoperatively. A micro-computerized tomography (${\mu}$-CT) of each specimen was taken for analysis of bone regeneration. Hematoxylin and Eosin stain were done to observe histological findings. Results: From the ${\mu}$-CT results, regenerated bone volume ($mm^3$) of 1% TC-loaded SFM, SFM, and control were $7.80{\pm}5.87$, $8.79{\pm}3.44$, and $10.61{\pm}5.3$ at 4 weeks postoperatively, respectively (P>0.05). Regenerated bone volume ($mm^3$) of 1% TC-loaded SFM, SFM, and control were $36.56{\pm}8.50$, $25.86{\pm}8.17$, and $19.09{\pm}5.07$ at 8 weeks postoperatively, respectively (P<0.05). Conclusion: The 1% TC-loaded SFM showed more bone regeneration than the SFM and the uncovered control, in guided bone regeneration.

가토의 두개 결손부에서의 실크 단백질과 platelet-rich fibrin (PRF)의 골형성 효과 (The bone regenerative effect of silk fibroin mixed with platelet-rich fibrin (PRF) in the calvaria defect of rabbit)

  • 송지영;권해용;권광준;박영욱;김성곤
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제36권4호
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    • pp.250-254
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    • 2010
  • Introduction: This study evaluated the bone regenerative effect of silk fibroin mixed with platelet-rich fibrin (PRF) of a bone defect in rabbits. Materials and Methods: Ten New Zealand white rabbits were used for this study and bilateral round shaped defects were formed in the parietal bone (diameter: 8.0 mm). The silk fibroin mixed with PRF was grafted into the right parietal bone (experimental group). The left side (control group) was grafted only PRF. The animals were sacrificed at 4 weeks and 8 weeks. A micro-computerized tomography (${\mu}$CT) of each specimen was taken. Subsequently, the specimens were decalcified and stained for histological analysis. Results: The average value of plane film analysis was higher in the experimental group than in the control group at 4 weeks and 8weeks after surgery. However, the difference was not statistically significant.(P>0.05) The tissue mineral density (TMD) in the experimental group at 4 weeks after surgery was significantly higher than the control group.(P<0.05) Conclusion: Silk fibroin can be used as a scaffold of PRF for rabbit calvarial defect repair.

폐동맥색전술로 치료된 Rasmussen 동맥류 1예 (A Case of Rasmussen Aneurysm Treated by Pulmonary Arterial Embolization)

  • 박성오;고혁;김수희;박완;이덕희;류대식;정복현
    • Tuberculosis and Respiratory Diseases
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    • 제51권1호
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    • pp.53-58
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    • 2001
  • 기관지 동맥 색전술에도 불구하고 반복되는 대량 객혈을 보이는 동공성 폐결핵 환자에서 나선형 CT를 이용하여 Rassmusen 동맥류의 위치 및 크기를 비교적 정확히 진단하여 coil 이용한 경도관 폐동맥 색전술로 성공적으로 지혈 시킨 사례를 경험하였기에 보고하는 바이다.

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경계요소법을 이용한 한국인 머리관련 전달함수의 특성 해석 (Boundary Element Analysis for Head-Related Transfer Function in the Case of Korean Adults)

  • 이두호;안태수;기동환
    • 대한기계학회논문집A
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    • 제34권8호
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    • pp.1035-1044
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    • 2010
  • 머리관련 전달함수는 음원으로부터 이도의 입구까지 소리의 전달함수로 인간이 소리의 위치를 판단하는 데 중요한 역할을 하는 함수이다. HRTF 는 개인간의 편차가 크게 나는 것으로 알려져 있다. 본 논문에서는 한국인의 평균두형에 관해서 HRTF 를 해석하는 경계요소해석 모델을 개발하고 해석 결과와 실험결과와의 비교를 통해서 모델을 검증하였다. 또한 특정 성인에 대하여 CT 촬영을 통하여 두형, 귓바퀴 및 이도의 형상을 획득하여 이를 바탕으로 이도 내의 음향응답을 전 가청주파수에서 해석할 수 있는 모델을 개발하고 실험과의 비교를 통하여 모델을 검증하였다. 개발된 모델을 이용, 경계요소 해석을 수행하고 한국인 HRTF 의 특성에 영향을 미치는 인자를 살펴보았다.

3개 지역에 따른 허혈성 뇌혈관 질환의 요일 별 발생 특징 비교 (Weekly Variation of Ischemic Stroke Onset in 3 Regions)

  • 김소연;이상관;성강경;김현식;권소연;제준태;박만용;임진영;김윤식;문상관;김민수
    • 동의생리병리학회지
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    • 제23권5호
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    • pp.1167-1171
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    • 2009
  • Ischemic stroke has been the leading cause deaths and the critical disability. In addition, the clinical problem of ischemic stroke have the poor prognosis and high mortality rate. The study aim was to identify the incidence variation of ischemic stroke by days of the week and its relationship with residences in males. We analyzed 607 males patients with ischemic stroke diagnosed by magnetic resonance image or computerized tomography. They were admitted to the oriental hospital of Kyunghee, Daejeon, Wonkwang university. We analyzed the onset of ischemic stroke using a ${\chi}2$ test. The results showed significant weekly variation of ischemic stroke onset and the differences of weekly variation according to residences. A deeper knowlegde of the underlying weekly variation could be provide more effective insights for preventive approach.

Determination of Initial Beam Parameters of Varian 2100 CD Linac for Various Therapeutic Electrons Using PRIMO

  • Maskani, Reza;Tahmasebibirgani, Mohammad Javad;Hoseini-Ghahfarokhi, Mojtaba;Fatahiasl, Jafar
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권17호
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    • pp.7795-7801
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    • 2015
  • The aim of the present research was to establish primary characteristics of electron beams for a Varian 2100C/D linear accelerator with recently developed PRIMO Monte Carlo software and to verify relations between electron energy and dose distribution. To maintain conformity of simulated and measured dose curves within 1%/1mm, mean energy, Full Width at Half Maximum (FWHM) of energy and focal spot FWHM of initial beam were changed iteratively. Mean and most probable energies were extracted from validated phase spaces and compared with related empirical equation results. To explain the importance of correct estimation of primary energy on a clinical case, computed tomography images of a thorax phantom were imported in PRIMO. Dose distributions and dose volume histogram (DVH) curves were compared between validated and artificial cases with overestimated energy. Initial mean energies were obtained of 6.68, 9.73, 13.2 and 16.4 MeV for 6, 9, 12 and 15 nominal energies, respectively. Energy FWHM reduced with increase in energy. Three mm focal spot FWHM for 9 MeV and 4 mm for other energies made proper matches of simulated and measured profiles. In addition, the maximum difference of calculated mean electrons energy at the phantom surface with empirical equation was 2.2 percent. Finally, clear differences in DVH curves of validated and artificial energy were observed as heterogeneity indexes were 0.15 for 7.21 MeV and 0.25 for 6.68 MeV. The Monte Carlo model presented in PRIMO for Varian 2100 CD was precisely validated. IAEA polynomial equations estimated mean energy more accurately than a known linear one. Small displacement of R50 changed DVH curves and homogeneity indexes. PRIMO is a user-friendly software which has suitable capabilities to calculate dose distribution in water phantoms or computerized tomographic volumes accurately.

폐경 전과 폐경 후 비만 여성의 심박변이도에 관한 연구 (Heart Rate Variability in Obese Climacteric Women in Korea;Relations between Autonomic Nervous System Activity and Obesity)

  • 황덕상;황미자;이윤재;이경섭;송미연
    • 한방비만학회지
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    • 제8권1호
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    • pp.81-88
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    • 2008
  • Objectives To investigate the relationship between Heart Rate Variability and menopause among obese middle-aged women in Korea. Subjects and Methods Forty middle-aged women (age 49.05 $\pm$ 2.64 years) with BMI > $23kg/m^2$ were recruited by local advertisement. Blood profiles of estrogen, FSH, LH, glucose, total cholesterol, HDL-cholesterol, and triglyceride were measured. Autonomic Nervous System (ANS) was estimated by short-term spectral analysis of heart rate variability (HRV). Visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) were accessed using Computerized Tomography (CT), Bioimpedance Analysis (BIA), and anthropometry. To scrutinize the influence of ANS on obesity-related factors, we divided the subjects into pre- and post-menopausal women. Results The total cholesterol, FSH and LH were significantly higher in post-menopausal obese women group. The estradiol and standard deviation of all normal R-R intervals (SDNN), high-frequency components (HF) of the HRV were significantly lower in postmenopausal obese women group (P<0.05). Adipose tissue distribution and blood profiles were not significantly different between two groups. Conclusion Menopause induced a decrease in SDNN and HF values and increase in total cholesterol level in obese women although the VAT itself was not related with ANS in obese women.

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흉수의 혈관육종의 세포학적 소견 - 1예 보고 - (Cytologic Features of an Angiosarcoma in Pleural Fluid - A Case Report -)

  • 주영채;박인서;김윤주;한혜승;한지영
    • 대한세포병리학회지
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    • 제10권1호
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    • pp.61-66
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    • 1999
  • Angiosarcomas are rare tumors, seen most commonly in the skin and soft tissue of head and neck legion. But it has been described in numerous body sites including thyroid, breast, liver, spleen, bone, etc.. Their biological behaviors depend on the microscopic grade, site of origin, and multifocality. We report the unique cytological features of an angiosarcoma in pleural fluid. A 61-year-old woman presented with a 6 month history of dyspnea on exertion and chest pain. Chest computerized tomography(CT) revealed multiple subpleural small nodules in the right lung and widespread all space consolidation and pleural effusion in the left lung. CT of liver revealed multiple small low attenuated lesion. The smears obtained from pleural fluid showed hypocellularity with a hemorrhagic background. The tumor cells were highly pleomorphic oval or spindle in shape and presented singly, in loose groups, in knitted syncytial aggregates, and in acinar pattern. Their nuclei had vesicular chromatin with delineated, thick nuclear membranes and occasionally a large eosinophilic, prominent nucleolus. The cytoplasm was plump, thin or protected in spindly fashion. Almost ail tumor cells showed variable sized intracytoplasmic vacuoles and their nuclei were sometimes crescentic by a huge vacuole. Occasional binucleated tumor cells and mitotic figures were present. Cellular debris and streaky materials were identified. Needle biopsy specimen from the pleura revealed anastomosing slit-like spaces lined by pleomorphic tumor cells. The tumor cells showed a strong reactivity for CD31 and vimentin and focal weak reactivity for factor VIII-related antigen.

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