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  • Title/Summary/Keyword: CT-Number

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Extract and Analysis System for CT/MRI Images (CT/MRI 영상에서의 이미지 추출-분석 시스템)

  • Kwak, Ho-Young;Huh, Jisoon
    • Journal of the Korea Society of Computer and Information
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    • v.19 no.1
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    • pp.131-140
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    • 2014
  • TMost of the medical images that are being used today are to confirm the existence of lesions. These kind of medical images can not only be used to confirm lesions but if we could use it for academic studies or for analysis and reference materials for surgical operations, it could offer great help in medical studies. Furthermore, we could reduce the number of errors in treatment through simulations in the surgical operations and treatments. In this paper, the necessary parts regarding the medical image visuals were extracted through the point cloud and by using the information obtained through it, it manufactures the necessary information for academic studies, diagnoses or operations. By designing and realizing the system which makes simulation possible with the manufactured information, the paper attempts to provide a more effective way to approach academic studies or giving appropriate diagnoses in the treatment of patients.

Change of Proximal Descending Aortic False Lumen after Conventional Repair of Acute Type I Dissection: Is It Always Unfavorable?

  • Kim, Sue Hyun;Kim, Jun Sung;Shin, Yoon Cheol;Kim, Dong Jung;Lim, Cheong;Park, Kay-Hyun
    • Journal of Chest Surgery
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    • v.48 no.4
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    • pp.238-245
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    • 2015
  • Background: Some patients show favorable changes in the descending aortic false lumen after conventional repair of acute type A dissection, although the incidence of favorable changes has been reported to be low. We aimed to investigate the incidence of positive postoperative changes in the false lumen and the factors associated with positive outcomes. Methods: In 63 patients who underwent surgery for type A acute dissection as well as serial computed tomography (CT) scanning, morphological parameters were compared between the preoperative, early postoperative (mean interval, 5.4 days), and late CT scans (mean interval, 31.0 months) at three levels of the descending thoracic aorta. Results: In the early postoperative CT images, complete false lumen thrombosis and/or true lumen expansion at the proximal descending aorta was observed in 46% of the patients. In the late images, complete thrombosis or resolution of the proximal descending false lumen occurred in 42.9% of the patients. Multivariate analysis found that juxta-anastomotic false lumen thrombosis was predictive of favorable early changes, which were in turn predictive of continuing later improvement. Conclusion: Even after conventional repair without inserting a frozen elephant trunk, the proximal descending aortic false lumen showed positive remodeling in a substantial number of patients. We believe that the long-term prognosis of type A dissection can be improved by refining surgical technique, and particularly by avoiding large intimal tears at the anastomosis site during the initial repair.

Different Catabolism Pathways Triggered by Various Methylxanthines in Caffeine-Tolerant Bacterium Pseudomonas putida CT25 Isolated from Tea Garden Soil

  • Ma, Yi-Xiao;Wu, Xiao-Han;Wu, Hui-Shi;Dong, Zhan-Bo;Ye, Jian-Hui;Zheng, Xin-Qiang;Liang, Yue-Rong;Lu, Jian-Liang
    • Journal of Microbiology and Biotechnology
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    • v.28 no.7
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    • pp.1147-1155
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    • 2018
  • The degradation efficiency and catabolism pathways of the different methylxanthines (MXs) in isolated caffeine-tolerant strain Pseudomonas putida CT25 were comprehensively studied. The results showed that the degradation efficiency of various MXs varied with the number and position of the methyl groups on the molecule (i.e., xanthine > 7-methylxanthine theobromine > caffeine > theophylline > 1-methylxanthine). Multiple MX catabolism pathways coexisted in strain CT25, and a different pathway would be triggered by various MXs. Demethylation dominated in the degradation of N-7-methylated MXs (such as 7-methylxanthine, theobromine, and caffeine), where C-8 oxidation was the major pathway in the catabolism of 1-methylxanthine, whereas demethylation and C-8 oxidation are likely both involved in the degradation of theophylline. Enzymes responsible for MX degradation were located inside the cell. Both cell culture and cell-free enzyme assays revealed that N-1 demethylation might be a rate-limiting step for the catabolism of the MXs. Surprisingly, accumulation of uric acid was observed in a cell-free reaction system, which might be attributed to the lack of activity of uricase, a cytochrome c-coupled membrane integral enzyme.

Utility of Lateral Circumflex Femoral Artery Perforator's 3D Image with MD-CT (MD-CT로 얻은 가쪽넙다리휘돌이 관통동맥 3D 영상의 유용성)

  • Park, Soo Ho;Shim, Jeong Su;Lee, Sang Kon;Park, Dae Hwan
    • Archives of Plastic Surgery
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    • v.35 no.4
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    • pp.379-384
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    • 2008
  • Purpose: Currently, using perforator artery flaps especially anterolateral thigh flaps are widely used for reconstruction of extremities, head and neck. Obtaining a precise anatomical picture prior to operation will translate to a more accurate, efficient and safe procedure. Authors used 3D-image work up via 64-slice MDCT to make a more precise preoperative plan. Methods: A total of 10 patients underwent soft tissue reconstruction with anterolateral thigh flap from December 2006 to December 2007. The 64-Channel MDCT (LightSpeed VCT, GE, USA) was used and 3D images were reconstructed. Findings from MDCT were applied to the preoperative planning and confirmed with intraoperative findings. Results: The average number of perforator arteries from lateral circumflex femoral artery was 2. The average lengths of vascular pedicle from the origin of lateral circumflex femoral artery to the first and second perforator artery were 11.0 cm and 20.0 cm, respectively. The average diameter of the pedicle artery was 2.2 mm. The locations of the perforator arteries were mapped and localized on the body surface based on the MDCT result. These were confirmed through direct visualization intraoperatively. Conclusion: MDCT has an advantage of obtaining accurate images of the general anatomy and even fine structures like perforator arteries. By using this state-of-the-art diagnostic imaging technique, it is now possible to make an operative plan safely and easily.

The three-dimensional microstructure of trabecular bone: Analysis of site-specific variation in the human jaw bone

  • Kim, Jo-Eun;Shin, Jae-Myung;Oh, Sung-Ook;Yi, Won-Jin;Heo, Min-Suk;Lee, Sam-Sun;Choi, Soon-Chul;Huh, Kyung-Hoe
    • Imaging Science in Dentistry
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    • v.43 no.4
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    • pp.227-233
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    • 2013
  • Purpose: This study was performed to analyze human maxillary and mandibular trabecular bone using the data acquired from micro-computed tomography (micro-CT), and to characterize the site-specific microstructures of trabeculae. Materials and Methods: Sixty-nine cylindrical bone specimens were prepared from the mandible and maxilla. They were divided into 5 groups by region: the anterior maxilla, posterior maxilla, anterior mandible, posterior mandible, and mandibular condyle. After the specimens were scanned using a micro-CT system, three-dimensional microstructural parameters such as the percent bone volume, bone specific surface, trabecular thickness, trabecular separation, trabecular number, structure model index, and degrees of anisotropy were analyzed. Results: Among the regions other than the condylar area, the anterior mandibular region showed the highest trabecular thickness and the lowest value for the bone specific surface. On the other hand, the posterior maxilla region showed the lowest trabecular thickness and the highest value for the bone specific surface. The degree of anisotropy was lowest at the anterior mandible. The condyle showed thinner trabeculae with a more anisotropic arrangement than the other mandibular regions. Conclusion: There were microstructural differences between the regions of the maxilla and mandible. These results suggested that different mechanisms of external force might exist at each site.

Measurements of the Hepatectomy Rate and Regeneration Rate Using Deep Learning in CT Scan of Living Donors (딥러닝을 이용한 CT 영상에서 생체 공여자의 간 절제율 및 재생률 측정)

  • Sae Byeol, Mun;Young Jae, Kim;Won-Suk, Lee;Kwang Gi, Kim
    • Journal of Biomedical Engineering Research
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    • v.43 no.6
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    • pp.434-440
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    • 2022
  • Liver transplantation is a critical used treatment method for patients with end-stage liver disease. The number of cases of living donor liver transplantation is increasing due to the imbalance in needs and supplies for brain-dead organ donation. As a result, the importance of the accuracy of the donor's suitability evaluation is also increasing rapidly. To measure the donor's liver volume accurately is the most important, that is absolutely necessary for the recipient's postoperative progress and the donor's safety. Therefore, we propose liver segmentation in abdominal CT images from pre-operation, POD 7, and POD 63 with a two-dimensional U-Net. In addition, we introduce an algorithm to measure the volume of the segmented liver and measure the hepatectomy rate and regeneration rate of pre-operation, POD 7, and POD 63. The performance for the learning model shows the best results in the images from pre-operation. Each dataset from pre-operation, POD 7, and POD 63 has the DSC of 94.55 ± 9.24%, 88.40 ± 18.01%, and 90.64 ± 14.35%. The mean of the measured liver volumes by trained model are 1423.44 ± 270.17 ml in pre-operation, 842.99 ± 190.95 ml in POD 7, and 1048.32 ± 201.02 ml in POD 63. The donor's hepatectomy rate is an average of 39.68 ± 13.06%, and the regeneration rate in POD 63 is an average of 14.78 ± 14.07%.

Diagnosis of split fractures of the mandible in adults

  • Taesik Kim;Sung Gyun Jung;In Pyo Hong;Young Joong Hwang
    • Archives of Craniofacial Surgery
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    • v.24 no.4
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    • pp.167-173
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    • 2023
  • Background: Mandibular split fractures, in which the fracture occurs exclusively in the posterior wall, are uncommon. This study aimed to enhance clinicians' understanding of mandibular split fractures and offer insights for future research. Methods: This study included six patients who visited our hospital between January 2020 and June 2023 and were diagnosed with mandibular split fractures. We retrospectively collected data from patients' medical records on their age, sex, symptoms, mechanism, impact site, associated injuries, and treatment method, as well as the location, pattern, and number of fractures observed on computed tomography (CT) and panoramic images. The frequency of split fractures among all mandibular fractures was calculated. Results: The six patients included three men (50%) and three women (50%), ranging in age from 20 to 71 years (mean age, 49.8 years). The split fractures were located in the symphysis in one patient (16.7%), symphysis to parasymphysis in two patients (33.3%), parasymphysis in one patient (16.7%), and parasymphysis to the body in two patients (33.3%). Four patients (66.7%) had condylar head fractures, while two patients (33.3%) had single split fractures. The mechanism of trauma was a slip-down incident in four cases (66.7%), while two cases (33.3%) were caused by motorcycle traffic accidents. Four patients (67%) underwent intermaxillary fixation, while two patients (33%) improved with conservative treatment. Split fractures were diagnosed in all six patients on CT, whereas the fracture line was not clearly visible on panoramic images. Mandibular split fractures accounted for 5.6% of all mandibular fractures. Conclusion: This study provides insights into the clinical characteristics of rare mandibular split fractures and the diagnostic imaging findings. Furthermore, CT scans and three-dimensional image synthesis-instead of panoramic images-may be essential for accurately diagnosing mandibular fractures, including mandibular split fractures, in the future.

Thickness of Rectus Abdominis Muscle and Abdominal Subcutaneous Fat Tissue in Adult Women: Correlation with Age, Pregnancy, Laparotomy, and Body Mass Index

  • Kim, Jungmin;Lim, Hyoseob;Lee, Se Il;Kim, Yu Jin
    • Archives of Plastic Surgery
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    • v.39 no.5
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    • pp.528-533
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    • 2012
  • Background Rectus abdominis muscle and abdominal subcutaneous fat tissue are useful for reconstruction of the chest wall, and abdominal, vaginal, and perianal defects. Thus, preoperative evaluation of rectus abdominis muscle and abdominal subcutaneous fat tissue is important. This is a retrospective study that measured the thickness of rectus abdominis muscle and abdominal subcutaneous fat tissue using computed tomography (CT) and analyzed the correlation with the patients' age, gestational history, history of laparotomy, and body mass index (BMI). Methods A total of 545 adult women were studied. Rectus abdominis muscle and abdominal subcutaneous fat thicknesses were measured with abdominopelvic CT. The results were analyzed to determine if the thickness of the rectus abdominis muscle or subcutaneous fat tissue was significantly correlated with age, number of pregnancies, history of laparotomy, and BMI. Results Rectus abdominis muscle thicknesses were 9.58 mm (right) and 9.73 mm (left) at the xiphoid level and 10.26 mm (right) and 10.26 mm (left) at the umbilicus level. Subcutaneous fat thicknesses were 24.31 mm (right) and 23.39 mm (left). Rectus abdominismuscle thickness decreased with age and pregnancy. History of laparotomy had a significant negative correlation with rectus abdominis muscle thickness at the xiphoid level. Abdominal subcutaneous fat thickness had no correlation with age, number of pregnancies, or history of laparotomy. Conclusions Age, gestational history, and history of laparotomy influenced rectus abdominis muscle thickness but did not influence abdominal subcutaneous fat thickness. These results are clinically valuable for planning a rectus abdominis muscle flap and safe elevation of muscle flap.

Cooperative Analog and Digital (CANDI) Time Synchronization for Large Multihop Network (다중 홉 네트워크를 위한 디지털 및 아날로그 협동 전송 시간 동기화 프로토콜)

  • Cho, Sung-Hwan;Ingram, Mary Ann
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37C no.11
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    • pp.1084-1093
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    • 2012
  • For large multihop networks, large time synchronization (TS) errors can accumulate with conventional methods, such as TPSN, RBS, and FTSP, since they need a large number of hops to cover the network. In this paper, a method combining Concurrent Cooperative Transmission (CCT) and Semi- Cooperative Spectrum Fusion (SCSF) is proposed to reduce the number of hops to cover the large network. In CCT, cooperating nodes transmit the same digitally encoded message in orthogonal channels simultaneously, so receivers can benefit from array and diversity gains. SCSF is an analog cooperative transmission method where different cooperators transmit correlated information simultaneously. The two methods are combined to create a new distributed method of network TS, called the Cooperative Analog and Digital (CANDI) TS protocol, which promises significantly lower network TS errors in multi-hop networks. CANDI and TPSN are compared in simulation for a line network.

3D Reconstruction of Tissue from a few of MRI Images using Radial Basis Function (BBF를 이용한 적은 수의 MRI 이미지로부터 3차원 조직 재구성)

  • Shin, Young-Seok;Kim, Hyoung-Seok B.
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.11
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    • pp.2077-2082
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    • 2008
  • Recent the advanced technologies in medical imaging such as magnetic resonance imaging (MRI) and computed tomography (CT) make doctors improve the diagnostic skill with detailed anatomical information. In general, it is necessary to get a number of MRI images in order to obtain more detail information. However, the performance of MRI machines of privately run hospitals is not good and thus we may obtain only a few of MRI images. If 3D surface reconstruction is accomplished with a few slices, then it generates 3D surface of poor qualify. This paper propose a way to Set a 3D surface of high quality from a few of number of slices. First of all, our algorithm detects the boundary of tissues which we want to reconstruct as a 3D object and find out the set of vortices on the boundary. And then we generate a 3D implicit surface to interpolate the boundary points by using radial basis function. Lastly, we render the 3D implicit surface by using Marching cube algorithms.