• Title/Summary/Keyword: computer tomography

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Hemorrhargic Effusion Caused by Chronic Torsion of Right Middle Lung Lobe with Concurrent Ovarian Tumor in a Female Miniature Poodle Dog (난소종양이 병발한 암컷 푸들에서 오른쪽 중간엽 폐염전으로 인한 만성적인 출혈성 흉수 증례)

  • Kim, Tae-Hwan;Hong, Subin;Kim, Minkyung;Shin, Jeong-In;Jang, Yun-Sul;Lee, Jae-Hoon
    • Journal of Veterinary Clinics
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    • v.32 no.6
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    • pp.530-535
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    • 2015
  • An 11-year-old intact female miniature poodle presented with a four-month history of hemorrhagic effusion. The patient was alert on physical examination, although muffled heart sounds were noted upon auscultation of the right hemithorax. The radiographic finding was pleural effusion. Ultrasonography revealed cystic changes in both ovaries and several nodules in the liver. A refractory opacity in the right lung field, as visualized with computer tomography (CT), was diagnosed as right middle lung lobe torsion with a collapsed bronchus. Five days after diagnosis, a right fifth intercostal thoracotomy was performed to remove the right middle lung lobe; the right middle lung lobe was grossly shrunken as a result of chronic lung lobe torsion. Ovariohysterectomy was also performed. Histopathologic examination revealed papillary adenocarcinoma in both ovaries and suspected metastasized ovarian adenocarcinoma cells in the lung lobe. The patient recovered favorably and had been doing well up to two months post-surgery. However, after four months, the dog presented with respiratory difficulty. The radiographic findings were pleural effusion and collapse of the right cranial and left caudal lung lobes. Malignant cells of epithelial origin were observed in the pleural effusion. The tumor cells were suspected to be metastasized cells from the previously resected lung lobe. Although cancer treatment was recommended, the suggestion was suspended and the dog was discharged from hospital. This was a case of lung lobe torsion that had occurred because of hemorrhagic effusion due to tumor. Although ovariohysterectomy and lobectomy were performed, there was a relapse of hemorrhagic effusion because of metastasized tumor from the previously resected lung lobe.

The Protective Effects of IGF-1 on Different Subpopulations of DRG Neurons with Neurotoxicity Induced by gp120 and Dideoxycytidine In Vitro

  • Lu, Lin;Dong, Haixia;Liu, Guixiang;Yuan, Bin;Li, Yizhao;Liu, Huaxiang
    • Biomolecules & Therapeutics
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    • v.22 no.6
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    • pp.532-539
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    • 2014
  • Peripheral neuropathy induced by human immunodeficiency virus (HIV) infection and antiretroviral therapy is not only difficult to distinguish in clinical practice, but also difficult to relieve the pain symptoms by analgesics because of the severity of the disease at the later stage. Hence, to explore the mechanisms of HIV-related neuropathy and find new therapeutic options are particularly important for relieving neuropathic pain symptoms of the patients. In the present study, primary cultured embryonic rat dorsal root ganglion (DRG) neurons were used to determine the neurotoxic effects of HIV-gp120 protein and/or antiretroviral drug dideoxycytidine (ddC) and the therapeutic actions of insulin-like growth factor-1 (IGF-1) on gp120- or ddC-induced neurotoxicity. DRG neurons were exposed to gp120 (500 pmol/L), ddC ($50{\mu}mol/L$), gp120 (500 pmol/L) plus ddC ($50{\mu}mol/L$), gp120 (500 pmol/L) plus IGF-1 (20 nmol/L), ddC ($50{\mu}mol/L$) plus IGF-1 (20 nmol/L), gp120 (500 pmol/L) plus ddC ($50{\mu}mol/L$) plus IGF-1 (20 nmol/L), respectively, for 72 hours. The results showed that gp120 and/or ddC caused neurotoxicity of primary cultured DRG neurons. Interestingly, the severity of neurotoxicity induced by gp120 and ddC was different in different subpopulation of DRG neurons. gp120 mainly affected large diameter DRG neurons (> $25{\mu}m$), whereas ddC mainly affected small diameter DRG neurons (${\leq}25{\mu}m$). IGF-1 could reverse the neurotoxicity induced by gp120 and/or ddC on small, but not large, DRG neurons. These data provide new insights in elucidating the pathogenesis of HIV infection- or antiretroviral therapy-related peripheral neuropathy and facilitating the development of novel treatment strategies.

Radioimmunoscintigraphy Using IMACIS-1 in Gastrointestinal Cancer (IMACIS-1을 이용한 위장관 종양의 방사면역신티그램)

  • Sohn, Hyung-Sun;Kim, Choon-Yul;Bahk, Yong-Whee
    • The Korean Journal of Nuclear Medicine
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    • v.24 no.1
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    • pp.29-36
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    • 1990
  • Most of the diagnostic methods currently used for the detection of neoplastic masses provide indirect evidence. To obtain greater specificity in the interpretation of neoplasias by in vivo methods, the immunological approach appears to be most promising. Two problems that interfered with progress in this field were the lack of tumor specific antigen and the lack of well-defined and reproducible antibodies. To improve the sensitivity and specificity of radioimmunoscintigraphy as a technique for tumor localization, the use of monoclonal antibodies, fragments of antibodies and single photon emission computerized tomography (SPECT) are reasonable. The obvious advantages of monoclonal antibodies are their homogeneity, their specificity for the immunizing antigen and the reaction with a single determinant-thus no large immunecomplexes with antigen are formed. Monoclonal antibody technique has recently provided an opportunity to reevaluate the role of nuclear medicine for the diagnosis of malignant diseases by using the immunological approach. Out first results by means of radioimmunoscintigraphy of CEA and CA 19-9 producing tumors using a cocktail of fragments F $(ab')_2$, of mocolonal antibodies to CA 19-9 and CEA labeled with $^{131}I$ (IMACIS-1) are reported. The aims of this investigation was to evaluate the role of immunoscintigraphy in patients with colorectal and other cancers for diagnosis of local recurrences and metastasis. This report contains results of the first 8 colorectal and pancreas cancer patients with the elevation of the level of serum CEA and/or CA 19-9. IMACIS-1 was injected intravenously during 30 minutes in 100 ml saline solution after skin test. Planar scintigrams were recorded 3, 5 and 7 days after the injection of the IMACIS-1. Anterior, lateral and posterior views of the liver as well as anterior and posterior views of the pelvis were obtained in each patients as an $^{131}I-antibody$ image. We were able to localize exactly the malignant process with the double-nuclide double-compound $^{99m}Tc\;^{131}I$ (Tc+l) scintigrams. In Tc & I double-nuclide scintigraphy, computer subtraction display provided more clear localization of the tumor. We compared the results of radioimmunoscintigraphy with CT, ultrasonograms, conventional scintigrams. The results were as follows: 1) The sensitivity and specificity of radioimmunoscintigraphy using the fragments $F(ab')_2$ of the cocktails of CEA and CA 19-9 monoclonal antibodies were 80% and 100% respectively. 2) Tumor detection rate was not proportionated to the level of serum tumor markets. 3) Second tracer technique was essential for tumor localization as an anatomic landmark using double-nuclide scintigraphy. 4) A slow infusion of the antibodies was necessary to prevent the formation of large immune complexes. 5) Tumor/non-tumor radioactivity was most elevated at 7 days delayed imaging. 6) Using planar scintigraphic technique of $^{131}I$ labeled monoclonal antibodies are possible for imaging most of the tumors.

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Comparative study on the Shape between a Customized Finger Made by 3D Printing Technology, Real Small Finger, a plaster Small Finger, Based on CT Data (CT data 기반 3D 프린팅으로 제작된 Small Finger, 실제 Small Finger 그리고 석고 Small Finger 형상 비교 연구)

  • Choi, Hyeun-Woo;An, Do-Hyun;Rhee, Do-byung;Lee, Jong-Min;Seo, Anna
    • Journal of the Korean Society of Radiology
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    • v.13 no.2
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    • pp.153-158
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    • 2019
  • The purpose of this study is to compare and analyse the differences between a customized small finger made by 3D printing technology, a real small finger, and the other made from plaster of an orthotic company. The areas and the volumes of each cross-section were measured by Computer tomography(CT) and a 3D scanner and analysis of variance was performed to find out the differences of each shape. The areas of the point of 15.69mm, Distal Interphalangel Joints, were measured 30 times respectively using the caliper toll function of Picture Archiving Communication System(PASC) program. The volumes were measured by Configure Units of Meshmixer Program. There was no significant difference in the areas between three of them and there was 0.2 mm gap in the volume, which was more than the significance probability. Therefore, the result of this study shows the availability of finger orthoses made by 3D printing technology in the medical field.

Digital technique in diagnosis and restoration of maxillary anterior implant: a case report (디지털 기법을 활용한 상악 전치부의 진단 및 수복 증례)

  • Haemin, Bang;Woohyung, Jang;Chan, Park;Kwi-Dug, Yun;Hyun-Pil, Lim;Sangwon, Park
    • Journal of Dental Rehabilitation and Applied Science
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    • v.38 no.4
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    • pp.249-256
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    • 2022
  • The implant prosthesis of anterior maxilla requires careful consideration in planning. In order to satisfy both esthetic and functional needs of a patient, fusion of intra-oral scan in Cone-beam computed tomography (CBCT) and facial scan can be considered. Bony structures and soft tissues captured in CBCT and occlusal surfaces of intra oral scan were incorporated into personal characteristics from facial scan. The patient had insufficient buccal bone on maxillary anterior area. The maxillary implants could not be placed on the most ideal position. However, the "top down" approach completed by computer-generated arranging of teeth in implant planning and surgery with surgical guide resulted in esthetically and functionally satisfying result regardless of the limitation. Careful diagnosis with digital technique and the usage of surgical guide resulted in successful surgery and esthetic restoration. The temporary fixed prostheses were designed, restored and evaluated. The patient was not satisfied with the first design of temporary prosthesis, which showed uneven space distribution between teeth due to the position of maxillary implant. The design was modified by changing proximal emergence contours and line angle to alter the perceived since of incisors. The patient was satisfied with the new design of provisional restoration. A digital occlusion analyzer (Arcus Digma II, KaVo, Leutkirch, Germany) was used to measure inherent condylar guidance and anterior guidance of a patient to provide a definitive prosthesis.

Reliability of Skeletal Muscle Area Measurement on CT with Different Parameters: A Phantom Study

  • Dong Wook Kim;Jiyeon Ha;Yousun Ko;Kyung Won Kim;Taeyong Park;Jeongjin Lee;Myung-Won You;Kwon-Ha Yoon;Ji Yong Park;Young Jin Kee;Hong-Kyu Kim
    • Korean Journal of Radiology
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    • v.22 no.4
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    • pp.624-633
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    • 2021
  • Objective: To evaluate the reliability of CT measurements of muscle quantity and quality using variable CT parameters. Materials and Methods: A phantom, simulating the L2-4 vertebral levels, was used for this study. CT images were repeatedly acquired with modulation of tube voltage, tube current, slice thickness, and the image reconstruction algorithm. Reference standard muscle compartments were obtained from the reference maps of the phantom. Cross-sectional area based on the Hounsfield unit (HU) thresholds of muscle and its components, and the mean density of the reference standard muscle compartment, were used to measure the muscle quantity and quality using different CT protocols. Signal-to-noise ratios (SNRs) were calculated in the images acquired with different settings. Results: The skeletal muscle area (threshold, -29 to 150 HU) was constant, regardless of the protocol, occupying at least 91.7% of the reference standard muscle compartment. Conversely, normal attenuation muscle area (30-150 HU) was not constant in the different protocols, varying between 59.7% and 81.7% of the reference standard muscle compartment. The mean density was lower than the target density stated by the manufacturer (45 HU) in all cases (range, 39.0-44.9 HU). The SNR decreased with low tube voltage, low tube current, and in sections with thin slices, whereas it increased when the iterative reconstruction algorithm was used. Conclusion: Measurement of muscle quantity using HU threshold was reliable, regardless of the CT protocol used. Conversely, the measurement of muscle quality using the mean density and narrow HU thresholds were inconsistent and inaccurate across different CT protocols. Therefore, further studies are warranted in future to determine the optimal CT protocols for reliable measurements of muscle quality.

Adaptation of Deep Learning Image Reconstruction for Pediatric Head CT: A Focus on the Image Quality (소아용 두부 컴퓨터단층촬영에서 딥러닝 영상 재구성 적용: 영상 품질에 대한 고찰)

  • Nim Lee;Hyun-Hae Cho;So Mi Lee;Sun Kyoung You
    • Journal of the Korean Society of Radiology
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    • v.84 no.1
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    • pp.240-252
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    • 2023
  • Purpose To assess the effect of deep learning image reconstruction (DLIR) for head CT in pediatric patients. Materials and Methods We collected 126 pediatric head CT images, which were reconstructed using filtered back projection, iterative reconstruction using adaptive statistical iterative reconstruction (ASiR)-V, and all three levels of DLIR (TrueFidelity; GE Healthcare). Each image set group was divided into four subgroups according to the patients' ages. Clinical and dose-related data were reviewed. Quantitative parameters, including the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), and qualitative parameters, including noise, gray matter-white matter (GM-WM) differentiation, sharpness, artifact, acceptability, and unfamiliar texture change were evaluated and compared. Results The SNR and CNR of each level in each age group increased among strength levels of DLIR. High-level DLIR showed a significantly improved SNR and CNR (p < 0.05). Sequential reduction of noise, improvement of GM-WM differentiation, and improvement of sharpness was noted among strength levels of DLIR. Those of high-level DLIR showed a similar value as that with ASiR-V. Artifact and acceptability did not show a significant difference among the adapted levels of DLIR. Conclusion Adaptation of high-level DLIR for the pediatric head CT can significantly reduce image noise. Modification is needed while processing artifacts.

Three Dimensional Measurements of Pore Morphological and Hydraulic Properties (토양 공극 형태와 수문학적 특성에 대한 3 차원적 측정)

  • Chun, Hyen-Chung;Gimenez, Daniel;Yoon, Sung-Won;Heck, Richard;Elliot, Tom;Ziska, Laise;Geaorge, Kate;Sonn, Yeon-Kyu;Ha, Sang-Keun
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.4
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    • pp.415-423
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    • 2010
  • Pore network models are useful tools to investigate soil pore geometry. These models provide quantitative information of pore geometry from 3D images. This study presents a pore network model to quantify pore structure and hydraulic characteristics. The objectives of this work were to apply the pore network model to characterize pore structure from large images to quantify pore structure, calculate water retention and hydraulic conductivity properties from a three dimensional soil image, and to combine measured hydraulic properties from experiments with calculated hydraulic properties from image. Soil samples were taken from a site located at the Baltimore science center, which is located inside of the city. Undisturbed columns were taken from the site and scanned with a computer tomographer at resolutions of 22 ${\mu}m$. Pore networks were extracted by medial-axis transformation and were used to measure pore geometry from one of the scanned samples. Water retention and unsaturated hydraulic conductivity values were calculated from the soil image. Properties of soil bulk density, water retention and unsaturated hydraulic conductivity were measured from three replicates of scanned soil samples. 3D image analysis provided accurate detailed pore properties such as individual pore volumes, pore length, and tortuosity of all pores. These data made possible to calculate accurate estimations of water retention and hydraulic conductivity. Combination of the calculated and measured hydraulic properties gave more accurate information on pore sizes over wider range than measured or calculated data alone. We could conclude that the hydraulic property computed from soil images and laboratory measurements can describe a full structure of intra- and inter-aggregate pores in soil.

Stress Patterns in the Reconstructed Double Bundles of the Anterior Cruciate Ligament in Response to an Anterior Tibial Load and Rotatory Load: an Analysis using a 3-Dimensional Finite Element Model (삼차원 유한 요소 모델을 이용한 전방십자인대 이중다발 재건술 후 전방 전위 및 회전 부하에 따른 이식건 응력 양상 분석)

  • Seo, Young-Jin;Song, Si Young;Ahn, Jung Tae;Kim, Yoon-Sang;Ko, Jun Ho;Jang, Seong-Wook;Yoo, Yon-Sik
    • Journal of the Korean Arthroscopy Society
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    • v.16 no.2
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    • pp.160-166
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    • 2012
  • Purpose: The aim of this study was to determine the patterns of the stress distribution within the reconstructed anterior cruciate ligament (ACL) double bundles in response to an anterior tibial load and rotatory load at $45^{\circ}$ flexed knee model by use of a 3-dimensional finite element analysis (FEM). Materials and Methods: The $0^{\circ}$ and $45^{\circ}$ flexed 3-D knee model were reconstructed based on the high resolution computed tomography (CT) images from the right knee of a healthy male subject. To simulate double bundle ACL reconstruction, in $0^{\circ}$ analytic model, four 7 mm diameter tunnels were created at the center of each anteromedial (AM) and posterolateral (PL) footprints on the femur and tibia. The grafts were inserted into the corresponding bone tunnels and then reconstructed knee model was flexed to $45^{\circ}$. As a next step, the 5 mm anterior tibial load and internal rotational load of $10^{\circ}$ were applied on the final Computer aided design (CAD) model. And then stress patterns of each bundle were assessed using a finite element analysis. Results: In response to the 5 mm of anterior tibial load, the AM bundle showed increased stresses around the tibial and femoral attachment sites; especially in the anterior aspect of the bundle. In the PL bundle, the highest stress concentration was also noticed on the anterior aspect of the bundle. Under $10^{\circ}$ internal rotational load, the stress concentration was predominant around the anterior aspect of the tibial attachment site within the AM bundle. The PL bundle also showed highest stress concentration on the anterior aspect of the bundle. Conclusion: Although the stress patterns were not identical among the AM and PL bundle, there were common trends in the stress distribution. The stress concentration was predominant on the anterior aspect of both bundles in response to the anterior tibial load and rotatory load.

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Development of Adaptive Spatial Filter to Improve Noise Characteristics of PET Images (PET 영상의 잡음개선을 위한 적응적 공간 필터 개발)

  • Woo, S. K.;Choi, Y.;Im, K. C.;Song, T. Y.;Jung, J. H.;Lee, K. H.;Kim, S. E.;Choe, Y. S.;Park, C. C.;Kim, B. T.
    • Journal of Biomedical Engineering Research
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    • v.23 no.3
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    • pp.253-261
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    • 2002
  • A spatially adaptive falter was formulated to imrove PET image qualify and the Performance of the filter was evaluated using simulation and phantom and human PET studies. In the proposed filter. if a pixel was identified as the edge Pixel, the Pixel value was Preserved. Otherwise a Pixel was replaced by the mean of the pixel values weighted by 2:7: 2. A Pixel was identified as the edge Pixel. if it satisfies the following conditions : the number of ADs (absolute difference between center and neighborhood pixels) which is smaller than THl (($pix_max{\times}0.1/log_2(NPM)$, NPM : mean of 6 neighborhood pixels excluding minimum and maximum) is 8-k and the number of ADs which is lager than TH2 ($NPM{\times}0.1$) is k. where k : 2, 3, …, 6. The results of this study demonstrate the superior performance of the Proposed titter compared to Gaussian fitter, weight median filter and subset averaged median filter. The proposed tittering method is simple but effective in increasing uniformity and contrast with minimal degradation of spatial resolution of PET images and thus. is expected to Provide improved diagnositc quality PET images .