• Title/Summary/Keyword: Computed tomography(CT)

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Clinical Features of Infectious Ileocecitis in Children (소아 감염성 회장맹장염의 임상적 고찰)

  • Lee, Tae-Ho;Hong, Yoo-Rha;Yeon, Gyu-Min;Lee, Jun-Woo;Park, Jae-Hong
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.13 no.1
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    • pp.30-35
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    • 2010
  • Purpose: Infectious ileocecitis is an infection confined to the ileocecal area and one of the most common causes of pediatric abdominal pain. This study was performed to demonstrate the clinical features of infectious ileocecitis in children. Methods: The medical records and radiologic findings of 37 patients with ileocecitis diagnosed by ultrasonography and/or computed tomography, who were admitted to Pusan National University Hospital from January 2004 and July 2008, were reviewed retrospectively. Viral gastroenteritis and secondary ileocecitis were excluded. Results: The mean age of the patients was 4.8${\pm}$3.4 years. One-half of the patients were preschool children. The chief complaint was abdominal pain (75.7%), diarrhea (10.8%), and vomiting (8.1%). Accompanying symptoms were fever (56.8%), vomiting (21.6%), and diarrhea (16.2%). The mean duration of abdominal pain, fever, diarrhea, and vomiting was 3.8${\pm}$2.1, 3.0${\pm}$1.9, 3.4${\pm}$1.9, and 2.4${\pm}$2.3 days, respectively. The frequency of diarrhea and vomiting was 5.8${\pm}$2.2 and 4.0${\pm}$2.8 per day, respectively. Diagnosis was made by abdominal ultrasonography in 22 patients (59.5%), abdominal CT in 2 patients (5.4%), and both modalities in 13 patients (35.1%). Besides the radiologic finding of thickening of the bowel wall, mesenteric lymphadenitis (59.5%), ascites (5.4%), and both mesenteric lymphadenitis and ascites (16.2%) were revealed. The mean duration of illness was 7.5${\pm}$5.0 days. There were no specific laboratory findings, and culture studies with stool or blood were negative. All of the patients recovered completely without specific treatment. Conclusion: Infectious ileocecitis has acute appendicitis-mimicking symptoms, but is self-limited within a few days, thus unnecessary treatment and work-up is avoided. However, distinguishing infectious ileocecitis from appendicitis, inflammatory bowel disease, and mesenteric lymphadenitis is important.

Effect of Matrigel for Bone Graft using Hydroxyapatite/Poly $\varepsilon$-caprolactone Scaffold in a Rat Calvarial Defect Model (랫드의 두개골결손부 모델에서 HA/PCL 지지체를 사용한 골이식 시 Matrigel의 효과)

  • Kim, Se-Eun; Shim, Kyung-Mi;Kim, Seung-Eon;Choi, Seok-Hwa;Bae, Chun-Sik;Han, Ho-Jae;Kang, Seong-Soo
    • Journal of Veterinary Clinics
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    • v.27 no.4
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    • pp.325-329
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    • 2010
  • The osteogenic potential of hydroxyapatite/poly $\varepsilon$-caprolactone composite (HA/PCL) scaffolds with matrigel was evaluated in a rat calvarial defect model. Calvarial defect formation was surgically created in Sprague Dawley rats (n = 18). HA/PCL scaffold was grafted with matrigel (M-HA/PCL group, n = 6) or without matrigel (HA/PCL group, n = 6). A critical defect group (CD group, n = 6) did not received a graft. Four weeks after surgery, bone formation was evaluated with radiography, micro computed tomography (micro CT) scanning, and histologically. No bone tissue formation was radiographically evident in the CD group. Bone tissue was radiographically evident in the HA/PCL and M-HA/PCL groups, however, there was more bone-similar opacity in the M-HA/PCL group. Micro CT analysis revealed that the bone volume of the M-HA/PCL group was higher than the HA/PCL group, however, no significant difference was found between the HA/PCL and M-HA/PCL groups. Bone mineral density in the M-HA/ PCL group was significantly higher than in the HA/PCL group (p < 0.05). Histologically, new bone was formed only from existing bone in the CD group, showing concavity without bone formation in the defect. In the HA/PCL group, new bone formation was only derived from existing bone, while in the M-HA/PCL group the largest bone formation was observed, with new bone tissue forming at the periphery of existing bone and around the HA/PCL scaffold with matrigel. The results indicate that the combination of HA/PCL scaffold with matrigel may be an effective means of enhancing bone formation in critical-sized bone defects.

The Characteristics of Eosinophilc Lung Diseases Cause by Toxocara Canis Larval Infestation (개회충 유충 감염에서 발생되는 호산구성 폐질환의 특성)

  • Kim, Yu Jin;Kyung, Sun Young;An, Chang Hyeok;Lim, Young Hee;Park, Jung Woong;Jeong, Seong Hwan;Lee, Sang Pyo;Choi, Dong Chull;Jeong, Young Bae;Kang, Shin Yong
    • Tuberculosis and Respiratory Diseases
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    • v.62 no.1
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    • pp.19-26
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    • 2007
  • Background: Toxocariasis is a common cause of eosinophilia and eosinophilic lung disease in Korea. We analyzed the characteristics of eosinophilic lung disease in toxocariasis. Method: One hundred and forty one patients with eosinophilia caused by a toxocara larval infection were evaluated from September 1, 2001 through March 30, 2006. The plain chest x-ray, chest CT(computed tomography), and bronchoalveolar larvage(BAL) were examined. A diagnosis of toxocariasis was made by ELISA using that secretory-excretory antigen from the T. canis larvae. Results: Toxocarial eosinophilic lung diseases was diagnosed in 32 out of 141 patients. Ground glass attenuation was the main feature on the CT scans in 23 out of 141 patients (71.9%). Thirteen patients (40.6%) had a random in zonal distribution on CT. Pleural effusion was observed in 9 patients (28.1%). Twenty eight patients (87.5%) complained of respiratory symptoms. Eleven patients (34.4%) had gastrointestinal symptoms and 12 patients (37.5%) had liver infiltration. Conclusions: The most common findings of the chest CT in patients with toxocariasis was a randomly distributed ground grass attenuation. A toxocara infection should be considered in a differential diagnosis of patients who exhibit pulmonary infiltration with eosinophilia in Korea.

Analysis of Mediatinal Lymph Nodes with Internal Low Density on Contrast Enhanced CT Scan (조영종강 전산화단층촬영상 내부 저밀도 음영을 보이는 종격동 림프절의 분석)

  • Ryu, Young-Hoon;Choe, Kyu-Ok;Hong, Yong-Kook;Kim, Sung-Kyu;Chang, Joon;Lee, Won-Young
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.2
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    • pp.264-279
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    • 1997
  • Background : To analyze the morphologic characteristics of low density lymph node in etiologic differentiation of lymphadenopathy, emphasizing the different features between tuberculosis and lung cancer, on contrast enhanced CT scan. Method : A total of 64 patients who showed low density lymph nodes on chest CT scan were analyzed. Primary causes were tuberculosis (n=28), lung cancer (n=27), malignant lymphoma (n=5) and metastasis from extrathoracic malignancies (n=4). CT scan was performed with 10mm slice thickness and 7 characteristic features were evaluated : location, size, presence or absence of the nonnecrotic lymph node, calcification, perinodal fat obliteration, thickness and evenness of the enhancing rim. Results : In patients with tuberculous lymphadenopathy, lymph nodes with uneven (68.0%) and thick (62.1%) enhancing rim were more common than lung cancer (p<0.05). Low density lymph nodes with less than 1 cm in size were found only in tuberculous lymphadenopathy(n=10). In 48.2% of patients with lung cancer, more than 1 nonnecrotic enlarged lymph node were coexisted, whereas 21.4% in patients with tuberculous lymphadenopathy(p=0.06). However, the size, location and calcification were not statistically significant between tuberculous lymphadenopathy and lung cancer. Conclusion : Tuberculous lymphadenopathy is strongly suggested when enhancing rim of enlarged lymph nodes is uneven and thick, when the coexisting nonnecrotic lymph nodes are few in number and when central low density is encountered in normal sized lymph nodes.

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Usefulness of Abdominal Compressor Using Stereotactic Body Radiotherapy with Hepatocellular Carcinoma Patients (토모테라피를 이용한 간암환자의 정위적 방사선치료시 복부압박장치의 유용성 평가)

  • Woo, Joong-Yeol;Kim, Joo-Ho;Kim, Joon-Won;Baek, Jong-Geal;Park, Kwang-Soon;Lee, Jong-Min;Son, Dong-Min;Lee, Sang-Kyoo;Jeon, Byeong-Chul;Cho, Jeong-Hee
    • The Journal of Korean Society for Radiation Therapy
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    • v.24 no.2
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    • pp.157-165
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    • 2012
  • Purpose: We evaluated usefulness of abdominal compressor for stereotactic body radiotherapy (SBRT) with unresectable hepatocellular carcinoma (HCC) patients and hepato-biliary cancer and metastatic liver cancer patients. Materials and Methods: From November 2011 to March 2012, we selected HCC patients who gained reduction of diaphragm movement >1 cm through abdominal compressor (diaphragm control, elekta, sweden) for HT (Hi-Art Tomotherapy, USA). We got planning computed tomography (CT) images and 4 dimensional (4D) images through 4D CT (somatom sensation, siemens, germany). The gross tumor volume (GTV) included a gross tumor and margins considering tumor movement. The planning target volume (PTV) included a 5 to 7 mm safety margin around GTV. We classified patients into two groups according to distance between tumor and organs at risk (OAR, stomach, duodenum, bowel). Patients with the distance more than 1 cm are classified as the 1st group and they received SBRT of 4 or 5 fractions. Patients with the distance less than 1 cm are classified as the 2nd group and they received tomotherapy of 20 fractions. Megavoltage computed tomography (MVCT) were performed 4 or 10 fractions. When we verify a MVCT fusion considering priority to liver than bone-technique. We sent MVCT images to Mim_vista (Mimsoftware, ver .5.4. USA) and we re-delineated stomach, duodenum and bowel to bowel_organ and delineated liver. First, we analyzed MVCT images to check the setup variation. Second we compared dose difference between tumor and OAR based on adaptive dose through adaptive planning station and Mim_vista. Results: Average setup variation from MVCT was $-0.66{\pm}1.53$ mm (left-right) $0.39{\pm}4.17$ mm (superior-inferior), $0.71{\pm}1.74$ mm (anterior-posterior), $-0.18{\pm}0.30$ degrees (roll). 1st group ($d{\geq}1$) and 2nd group (d<1) were similar to setup variation. 1st group ($d{\geq}1$) of $V_{diff3%}$ (volume of 3% difference of dose) of GTV through adaptive planing station was $0.78{\pm}0.05%$, PTV was $9.97{\pm}3.62%$, $V_{diff5%}$ was GTV 0.0%, PTV was $2.9{\pm}0.95%$, maximum dose difference rate of bowel_organ was $-6.85{\pm}1.11%$. 2nd Group (d<1) GTV of $V_{diff3%}$ was $1.62{\pm}0.55%$, PTV was $8.61{\pm}2.01%$, $V_{diff5%}$ of GTV was 0.0%, PTV was $5.33{\pm}2.32%$, maximum dose difference rate of bowel_organ was $28.33{\pm}24.41%$. Conclusion: Despite we saw diaphragm movement more than 5 mm with flouroscopy after use an abdominal compressor, average setup_variation from MVCT was less than 5 mm. Therefore, we could estimate the range of setup_error within a 5 mm. Target's dose difference rate of 1st group ($d{\geq}1$) and 2nd group (d<1) were similar, while 1st group ($d{\geq}1$) and 2nd group (d<1)'s bowel_organ's maximum dose difference rate's maximum difference was more than 35%, 1st group ($d{\geq}1$)'s bowel_organ's maximum dose difference rate was smaller than 2nd group (d<1). When applicating SBRT to HCC, abdominal compressor is useful to control diaphragm movement in selected patients with more than 1 cm bowel_organ distance.

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Establishment of a Murine Model for Radiation-induced Bone Loss in Growing C3H/HeN Mice (성장기 마우스에서 방사선 유도 골소실 동물모델 확립)

  • Jang, Jong-Sik;Moon, Changjong;Kim, Jong-Choon;Bae, Chun-Sik;Kang, Seong-Soo;Jung, Uhee;Jo, Sung-Kee;Kim, Sung-Ho
    • Journal of Radiation Protection and Research
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    • v.40 no.1
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    • pp.10-16
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    • 2015
  • Bone changes are common sequela of irradiation in growing animal. The purpose of this study was to establish an experimental model of radiation-induced bone loss in growing mice using micro-computed tomography (${\mu}CT$). The extent of changes following 2 Gy gamma irradiation ($2Gy{\cdot}min^{-1}$) was studied at 4, 8 or 12 weeks after exposure. Mice that received 0.5, 1.0, 2.0 or 4.0 Gy of gamma-rays were examined 8 weeks after irradiation. Tibiae were analyzed using ${\mu}CT$. Serum alkaline phosphatase (ALP) and biomechanical properties were measured and the osteoclast surface was examined. A significant loss of trabecular bone in tibiae was evident 8 weeks after exposure. Measurements performed after irradiation showed a dose-related decrease in trabecular bone volume fraction (BV/TV) and bone mineral density (BMD), respectively. The best-fitting dose-response curves were linear-quadratic. Taking the controls into accounts, the lines of best fit were as follows: BV/TV (%) = $0.9584D^2-6.0168D+20.377$ ($r^2$ = 0.946, D = dose in Gy) and BMD ($mg{\cdot}cm^{-3}$) = $8.8115D^2-56.197D+194.41$ ($r^2$ = 0.999, D = dose in Gy). Body weight did not differ among the groups. No dose-dependent differences were apparent among the groups with regard to mechanical and anatomical properties of tibia, serum ALP and osteoclast activity. The findings provide the basis required for better understanding of the results that will be obtained in any further studies of radiation-induced bone responses.

Analysis of Dose Delivery Error in Conformal Arc Therapy Depending on Target Positions and Arc Trajectories (동적조형회전조사 시 표적종양의 위치변위와 조사반경의 변화에 따른 선량전달 오류분석)

  • Kang, Min-Young;Lee, Bo-Ram;Kim, You-Hyun;Lee, Jeong-Woo
    • Journal of radiological science and technology
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    • v.34 no.1
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    • pp.51-58
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    • 2011
  • The aim of the study is to analyze the dose delivery error depending on the depth variation according to target positions and arc trajectories by comparing the simulated treatment planning with the actual dose delivery in conformal arc therapy. We simulated the conformal arc treatment planning with the three target positions (center, 2.5 cm, and 5 cm in the phantom). For the experiments, IMRT body phantom (I’mRT Phantom, Wellhofer Dosimetry, Germany) was used for treatment planning with CT (Computed Tomography, Light speed 16, GE, USA). The simulated treatment plans were established by three different target positions using treatment planning system (Eclipse, ver. 6.5, VMS, Palo Alto, USA). The radiochromic film (Gafchromic EBT2, ISP, Wayne, USA) and dose analysis software (OmniPro-IMRT, ver. 1.4, Wellhofer Dosimetry, Germany) were used for the measurement of the planned arc delivery using 6 MV photon beam from linear accelerator (CL21EX, VMS, Palo Alto, USA). Gamma index (DD: 3%, DTA: 2 mm) histogram and dose profile were evaluated for a quantitative analysis. The dose distributions surrounded by targets were also compared with each plans and measurements by conformity index (CI), and homogeneity index (HI). The area covered by 100% isodose line was compared to the whole target area. The results for the 5 cm-shifted target plan show that 23.8%, 35.6%, and 37% for multiple conformal arc therapy (MCAT), single conformal arc therapy (SCAT), and multiple static beam therapy, respectively. In the 2.5 cm-shifted target plan, it was shown that 61%, 21.5%, and 14.2%, while in case of center-located target, 70.5%, 14.1%, and 36.3% for MCAT, SCAT, and multiple static beam therapy, respectively. The values were resulted by most superior in the MCAT, except the case of the 5 cm-shifted target. In the analysis of gamma index histogram, it was resulted of 37.1, 27.3, 29.2 in the SCAT, while 9.2, 8.4, 10.3 in the MCAT, for the target positions of center, shifted 2.5 cm and 5 cm, respectively. The fail proportions of the SCAT were 2.8 to 4 times as compared to those of the MCAT. In conclusion, dose delivery error could be occurred depending on the target positions and arc trajectories. Hence, if the target were located in the biased position, the accurate dose delivery could be performed through the optimization of depth according to arc trajectory.

Is Preventive Bilateral Surgery Needed in Case of Bilateral Bullae on HRCT at Unilateral Primary Spontaneous Pneumothorax (일차성 자연기흉의 고해상 CT에서 보이는 반대편 기포의 예방적 기포절제술이 필요한가?)

  • Han, Jong-Hee;Kang, Min-Woong;Yu, Jeong-Hwan;Kim, Yong-Ho;Na, Myung-Hoon;Lim, Seung-Pyung;Lee, Young;Yu, Jae-Hyeon
    • Journal of Chest Surgery
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    • v.40 no.3 s.272
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    • pp.215-219
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    • 2007
  • Background: Due to the advancement of video assisted thoracoscopic techniques, an operation for primary spontaneous pneumothorax is now considered a common procedure. However, whether a preventive operation is necessary when a contralateral bulla is found on High Resolution Computed Tomography (HRCT) at the time of the first primary spontaneous pneumothorax attack is still unknown. In this retrospective study, it was our intension to find whether contralateral bullae are related to the occurrence of pneumothorax. Material and Method: Between January 1999 and April 2006, 550 patients were admitted to the Chungnam University hospital with primary spontaneous pneumothorax, which was confirmed by the HRCT scans in 190 patents. In these 190 patients, 159 had not received a bilateral operation after their first primary spontaneous pneumothorax attack. In these 159 patients, the relationship between the presence of contralateral bullae and the occurrence of pneumothorax was measured. Result: In these 159 patients, 67 had contralateral bullae confirmed inform the HRCT scan, and 92 had no visible contralateral bullae, During the follow up period, 6 patients (8.9%) with contralateral bullae had an occurrence of contralateral pneumothorax, and 5 patients (5.4%) without contralateral bullae had an occurrence of contralateral pneumothorax. (p=0.529 [Fisher's exact test]) Conclusion: In patients with unilateral primary pneumothorax, an HRCT scan is a useful way of confirming contralateral pulmonary bullae. However, the presence of bullae is not a significant predictive sign of an occurrence of contralateral pneumothorax. Also, surgery for pneumothorax is not completely uncomplicated, and bilateral surgery is still doubtful. A further prospective study will be required to find the relationship between the bullae found on HRCT and the occurrence of pneumothorax.

A Study of Various Filter Setups with FBP Reconstruction for Digital Breast Tomosynthesis (디지털 유방단층영상합성법의 FBP 알고리즘 적용을 위한 다양한 필터 조합에 대한 연구)

  • Lee, Haeng-Hwa;Kim, Ye-Seul;Lee, Youngjin;Choi, Sunghoon;Lee, Seungwan;Park, Hye-Suk;Kim, Hee-Joung;Choi, Jae-Gu;Choi, Young-Wook
    • Progress in Medical Physics
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    • v.25 no.4
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    • pp.271-280
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    • 2014
  • Recently, digital breast tomosynthesis (DBT) has been investigated to overcome the limitation of conventional mammography for overlapping anatomical structures and high patient dose with cone-beam computed tomography (CBCT). However incomplete sampling due to limited angle leads to interference on the neighboring slices. Many studies have investigated to reduce artifacts such as interference. Moreover, appropriate filters for tomosynthesis have been researched to solve artifacts resulted from incomplete sampling. The primary purpose of this study is finding appropriate filter scheme with FBP reconstruction for DBT system to reduce artifacts. In this study, we investigated characteristics of various filter schemes with simulation and prototype digital breast tomosynthesis under same acquisition parameters and conditions. We evaluated artifacts and noise with profiles and COV (coefficinet of variation) to study characteristic of filter. As a result, the noise with parameter 0.25 of Spectral filter reduced by 10% in comparison to that with only Ramp-lak filter. Because unbalance of information reduced with decreasing B of Slice thickness filter, artifacts caused by incomplete sampling reduced. In conclusion, we confirmed basic characteristics of filter operations and improvement of image quality by appropriate filter scheme. The results of this study can be utilized as base in research and development of DBT system by providing information that is about noise and artifacts depend on various filter schemes.

Association of Hemoglobin A1c with Visceral Fat Measured by Computed Tomography in Nondiabetic Adults (당뇨병이 없는 농촌지역의 건강한 성인 남녀에서 당화혈색소와 내장지방과의 관계)

  • Han, A Lum;Shin, Sae-Ron;Park, Seong-Hoon;Lee, Jeong Mi
    • Journal of agricultural medicine and community health
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    • v.37 no.4
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    • pp.215-222
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    • 2012
  • Objective: A prediabetes hemoglobin A1c (HbA1c) level of 5.7%-6.4% is considered a risk factor for diabetes mellitus and cardiovascular disease (CVD) in the USA. In this study, we assessed the HbA1c and visceral fat levels as CVD risk factors in health check-up examinees who were not yet diagnosed with diabetes. Methods: Totally, 507 study subject were categorized as per criteria of the American Diabetes Association, depending on whether the HbA1c level was ${\geq}5.7%$ or <5.7%. Lipid levels, blood pressure, BMI (kg/$m^2$), total abdominal, and visceral fat levels were measured by computed tomography. Results: The mean of HbA1c in the male group was larger than the mean in the female group and their values were, respectively, $6.03{\pm}0.82%$ and $5.88{\pm}0.72%$(p<0.05). Only the mean values of age and visceral fat area were different between $HbA1c{\geq}5.7%$ and <5.7% in both male and female group(p<0.05). Visceral fat levels were significantly associated with HbA1c in the group of HbA1c ${\geq}5.7%$ (odds ratio=1.005, 95% CI 1.002~1.008). Conclusions: Visceral fat levels were significantly higher and correlated with the group which HbA1c level is ${\geq}5.7%$. This finding suggests that subjects who have high levels of HbA1c should be carefully monitored during prediabetes and should have chance to have health education programs.