• Title/Summary/Keyword: computed tomography, CT

Search Result 2,531, Processing Time 0.031 seconds

3-D CT Imaging of Pathological Bone Changes in a Rat Model of Adjuvant-Induced Arthritis

  • Shim, Kyung-Mi;Kim, Se-Eun;Kang, Seong-Soo
    • Journal of the Korean Society of Radiology
    • /
    • v.2 no.4
    • /
    • pp.41-46
    • /
    • 2008
  • Computed tomography (CT) is a medical imaging method employing tomography. CT is a 3-Dimensional (3-D) radiographic imaging technique, which is not suited for assessment of inflammation, but can be considered a reference method for assessment of bone damage, due to its direct 3-D visualization of calcified tissue. In this study of pathological joint changes in a rat model of adjuvant-induced arthritis (AIA) and quality analysis of bone destructions were performed by 3-Dimensional computed tomography images. These data demonstrate that the destructive progression of disease in a rat AIA model can be quantified using 3-D CT image analysis, which allows assessment of arthritic disease status and efficacy of experimental therapeutic agents.

  • PDF

Measurement of Patient Dose from Computed Tomography Using Physical Anthropomorphic Phantom (물리적 팬텀을 이용한 CT 촬영 환자의 피폭 선량 측정 및 평가)

  • Jang, Ki-Won;Lee, Choon-Sik;Kwon, Jung-Wan;Lee, Jai-Ki
    • Journal of Radiation Protection and Research
    • /
    • v.30 no.3
    • /
    • pp.113-119
    • /
    • 2005
  • The computed tomogrpahy(CT) provides a high quality in images of human body but contributes to the relatively high patient dose. The frequency of CT examination is increasing and, therefore, the concerns about the patient dose are also increasing. In this study the experimental determination of patient dose was performed by using a physical anthropomorphic phantom and thermoluminescent dosimeter(TLD). The measurements were done for the both axial and spiral scan mode. As a result the effective doses for each scan mode were 17.78mSv and 10.01 mSv respectively and the fact that the degree of the reduction in the patient dose depends on the pitch scan parameter was confirmed. The measurement methods suggested in this study can be applied for the reassessment of the patient dose when the technique in CT equipment is developed or the protocol for CT scanning is changed.

Algorithm to Shorten Imaging Time in Fluorescent X-ray Computed Tomogrpahy (형광 X선 CT에서 촬상 시간의 단축화 알고리즘)

  • 정남채
    • Journal of the Institute of Convergence Signal Processing
    • /
    • v.2 no.4
    • /
    • pp.46-52
    • /
    • 2001
  • In this paper it was examined both imaging system and processing algorithm for imaging's high speedization of fluorescent X-ray computed tomography using synchrotron radiation, The electronic system was used for dead time by about 6% but shortening of measure time was achieved by 2 seconds per 1 point. Also efficiency of reconstruction algorithm was proved, and memory and calculation amount was decreased by about 1/100 The fixed quantity was confirmed by physical phantom, and iodine distribution was presumed from image of thyroid gland in vitro These result shows realization possibility of fluorescent X-ray computed tomography measure in vivo.

  • PDF

A Study on the Analysis of Risk Factors and Correlations of Coronary Artery Disease of the Examinee taking Coronary Computed Tomography Angiography in a Comprehensive Health Improvement Center (종합검진 수검자의 관상동맥 전산화단층 혈관조영술 검사에서 관상동맥질환의 위험요인과 관련성 분석)

  • Choi, Min-Gyeong;Gwak, Jong-Hyeok;Kim, Gwang;Lee, Sam-Yol
    • Journal of the Korean Society of Radiology
    • /
    • v.13 no.7
    • /
    • pp.1005-1014
    • /
    • 2019
  • The purpose of this study is to evaluate the usefulness of coronary computed tomography angiography of coronary artery disease for the purpose fo health screening according to gender and age. In addition the association between hematological factors (Glucose, total cholesterol, visceral fat, body mass index, triglycerides, high density lipoprotein (HDL), low density lipoprotein (LDL)) and coronary artery disease is investigated. A retrospective analysis of coronary computed tomography angiography with 299 subjects showed that the detection rate of coronary artery disease was higher in men over 50 years of age and it was statistically significant. In particular, the prevalence rate of men (37.9%) was about 2 times higher than that of women (17.0%). Glucose and HDL as hematological factors associated with coronary artery disease were statistically significant. The prevention and management of coronary artery disease seems to require the control of glucose and high density lipoprotein (HDL). Although it is not statistically significant with other hematological factors, the need for management of coronary artery disease was identified. the coronary computed tomography angiography of coronary artery has higher radiation doses than other CT scans. Therefore, for the purpose of screening, coronary computed tomography angiography should be considered in consideration of the sex and age of the examinee, and detection of coronary artery disease through other non-invasive tests should be prioritized over coronary computed tomography angiography.

Study on the Validation of the Gated Cone-Beam Computed Tomography on Radiation Therapeutic Linear Accelerator (방사선치료용 선형가속기를 이용한 Gated Cone-Beam CT의 유용성 연구)

  • Seo, Jeong-Min;Kim, Chan-Hyeong;Park, Byoung-Suk;Park, Cheol-Soo;Jang, Hyon-Chol;Kim, Joung-Dae
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.16 no.10
    • /
    • pp.6932-6939
    • /
    • 2015
  • The respiration is one of important factor in the radiation therapy. The existing commercial method of cone-beam computed tomography on LINAC does not consider respiratory motion of patient hence the images are both distorted and inaccurate. In this study, the cone-beam computed tomography images have been reconstructed from back projection radiography of specific phase on breathing cycle which concerned about respiratory movement in radiation therapy. This study investigated how different between cone-beam CT images with and without gating respiratory movement, and this paper provides that guide and implementation of gated cone-beam CT on radiation therapeutic equipment.

Diagnostic imaging of malignant insulinoma in a dog

  • Choi, Jihye;Keh, Seoyeon;Kim, Sungsoo;Lee, Su-Hyung;Kim, Hyejin;Choi, Heeyeon;Lim, Younji;Kim, Hyunwook;Kim, Ahyoung;Kim, Dae-Yong
    • Korean Journal of Veterinary Research
    • /
    • v.52 no.3
    • /
    • pp.205-208
    • /
    • 2012
  • Endocrine test data from a 13-year old intact female Maltese was indicative of the presence of an insulinoma, however ultrasonography identified a pancreatic mass only after 10 months after the first admission. Following identification of both pancreatic tumor and hepatic metastasis on computed tomography (CT), surgical excision of the mass was attempted. However, total excision failed because of tumor adhesion to adjacent large vessels. The pancreatic mass was monitored over the next 25 months via ultrasonography, CT, and positron emission tomography-computed tomography (PET-CT). Histopathological and immunohistochemical data confirmed the diagnosis of insulinoma with hepatic metastasis.

Quantitative analysis of hemothorax by computed tomography (흉부 전산화 단층촬영을 이용한 혈흉의 정량분석)

  • 강청희
    • Journal of Chest Surgery
    • /
    • v.28 no.3
    • /
    • pp.228-232
    • /
    • 1995
  • Computed tomography[CT is an effective technique for the evaluation of the thorax following blunt trauma. To evaluate multiply injured 30 patients who were diagnosed as hemothorax in emergency room, computed tomography of thorax was done. The thickness of slice was one centimeter and the entire pleural cavity from the apex to the costophrenic angle was included in the evaluation. Integration and addition of the hemothorax area for each CT slice was made and amount of blood in the pleural cavity was estimated. The slice which showed largest area of hemothorax was selected and the height and width of the hemothorax area were measured. The number of slices which showed radiographic evidence of hemothorax was counted. Regression analysis was done and measured amount of hemothorax, the height and width of the hemothorax area for each slice and number of slices were put as variables. And following equation was derived. V=108.3A-0.8B-7.4C+84.7 [R2=0.74 [ V: amount of hemothorax, A: height, B: width, C: number of slices Total amount of blood from thoracic drainage was compared to the measured amount by computed tomography and the relation between the two values was statistically significant.[p=0.001 In conclusion, quantitative estimation of size of hemothorax was possible by the above equation and the process was very helpful for determination policy of treatment of individual patient.

  • PDF

Surface Extraction from Multi-material CT Data

  • Fujimori, Tomoyuki;Suzuki, Hiromasa
    • International Journal of CAD/CAM
    • /
    • v.6 no.1
    • /
    • pp.81-87
    • /
    • 2006
  • This paper describes a method for extracting surfaces from multi-material CT (Computed Tomography) data. Most contouring methods such as Marching Cubes algorithm assume that CT data are composed of only two materials. Some extended methods such as [3, 6] can extract surfaces from the multi-material (non-manifold) implicit representation. However, these methods are not directly applicable to CT data that are composed of three or more materials. There are two major problems that arise from fundamentals of CT. The first problem is that we have to use n(n-1)/2 threshold values for CT data contains n materials and select appropriately one threshold value for each boundary area. The second is that we cannot reconstruct only from CT data in which area three or more materials are adjacent each other. In this paper, we propose a method to solve the problems by using image analysis and demonstrate the effectiveness of the method with application examples construct polygon models from CT data of machine parts.

Invisible Parotid Gland Pleomorphic Adenoma on Contrast Enhanced-Computed Tomography (조영증강 전산화단층촬영검사에서 보이지 않는 이하선의 다형선종)

  • Heo, Jae Hyung;Kim, Da Mi;Koo, Bon Seok;Chang, Jae Won
    • Korean Journal of Head & Neck Oncology
    • /
    • v.32 no.2
    • /
    • pp.85-89
    • /
    • 2016
  • Pleomorphic adenomas is the most common tumor of parotid gland and usually located and confined in superficial lobe of parotid gland. Computed tomography (CT) is commonly used to initially evaluate salivary gland lesion, but contrast-enhanced CT may sometimes fail to reveal lesions in spite of a high clinical suspicion. For this reason, ultrasonography (US) can be used as the first-line image work-up in some cases of parotid gland benign tumors. We experienced a case of a 60-year-old woman without underlying disease presenting a palpable parotid mass in which the initial CT examination was reported as 'no obvious mass detected'. However, the lesion was revealed in US and histologically confirmed as pleomorphic adenoma. The patient underwent superficial parotidectomy through modified facelift incision. To the best of our knowledge, this is the first report of invisible major salivary gland tumor on CT in the Korean literature.