• Title/Summary/Keyword: 2D Imaging

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A Study of brain Atlases in Hippocampus Volume Measurement Using IBASPM (IBASPM을 이용한 해마체적 측정에서 뇌 Atlases에 대한 고찰)

  • Kim, Ju-ho;Lee, Ju-won;Kim, Seong-hu
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2014.10a
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    • pp.981-984
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    • 2014
  • Volumetric measurement of hippocampus using IBASPM, the 20's normal adults 10 people's brain images were acquired in order to assess the changes according to the type of the Atlas. Images was obtained using MPRAGE of a 3-D gradient echo pulse sequence on Head matrix coil of 1.5T MRI system. The results of Paired t-test using obtained volume of hippocampus depending on the type of the Atlas, Atlas69-Altas84, Atlas69-Atlas116(p=0.729, 0.729) in the left hippocampus and Atlas69-Atlas84, Atlas69-Atlas116(p=0.219, 0.219) in right hippocampal formation were no significant differences but in the area except this, there was significant difference(p=0.000). The volume of the hippocampus using Atlas84 and Atlas116, represented the same value and there was no significant difference. In the image analysis using the overlay of atlas image and original image, Atlas71 could be found that the area of hippocampus did mismatch. In the case of atlas used in this study, because it has been developed by the westerners, there are differences between brain of asian. It would be needed to development of new Atlas for high accuracy measurement of the volume of hippocampus.

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The Parathyroid Gland: An Overall Review of the Hidden Organ for Radiologists (부갑상선: 부갑상선 영상에 익숙하지 않은 영상의학과 의사들을 위한 전반적인 검토)

  • Suho Kim;Jung Hee Shin;Soo Yeon Hahn;Haejung Kim;Myoung Kyoung Kim
    • Journal of the Korean Society of Radiology
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    • v.85 no.2
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    • pp.327-344
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    • 2024
  • Parathyroid glands are small endocrine glands that regulate calcium metabolism by producing parathyroid hormone (PTH). These are located at the back of the thyroid gland. Typically, four glands comprise the parathyroid glands, although their numbers may vary among individuals. Parathyroid diseases are related to parathyroid gland dysfunction and can be caused by problems with the parathyroid gland itself or abnormal serum calcium levels arising from renal disease. In recent years, as comprehensive health checkups have become more common, abnormal serum calcium levels are often found incidentally in blood tests, after which several additional tests, including a PTH test, ultrasonography (US), technetium-99m sestamibi parathyroid scan, single-photon-emission CT (SPECT)/CT, four-dimensional CT (4D-CT), and PET/CT, are performed for further evaluation. However, the parathyroid gland remains an organ less familiar to radiologists. Therefore, the normal anatomy, pathophysiology, imaging, and clinical findings of the parathyroid gland and its associated diseases are discussed here.

Endocrinological Results of the Transsphenoidal Microsurgery for Cushing's Disease (쿠싱병에 대한 경접형동접근법의 내분비학적 결과)

  • Kim, Joon Soo;Kim, Chang Jin;Ha, Sang Soo;Kim, Jung Hoon;Lee, Jung Gyo;Kwun, Byung Duk;Hong, Sung Kwan;Lee, Ki Up;Lee, Bong Jae;Kim, Yong Jae;Choi, Choong Kon;Lee, Ho Gyu
    • Journal of Korean Neurosurgical Society
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    • v.30 no.5
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    • pp.611-621
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    • 2001
  • Objective : We analyzed the clinical and endocrinological results of the transsphenoidal microsurgery for ACTH secreting pituitary adenomas. Marerials and Methods : From October 1995 to August 2000, 18 patients underwent transsphenoidal microsurgery for Cushing's disease. We analyzed the surgical results of 17 patients, one patient who was previously operated from other hospital was excluded. Age of the patients were 18 to 61 years old(mean 37.7), male to female ratio was 1 : 3.3, and follow-up period was 3 to 50 months(mean 20.3). The selection of candidates for transsphenoidal exploration was based on endocrinologic criteria. Magnetic resonance imaging was the preferred radiologic test. Selective inferior petrosal sinus sampling of adrenocorticotropic hormone futher refined the diagnosis when endocrinologic and radiologic procedures were not definitive. Results : Results of the preoperative endocrinological test were : level of serum ACTH 29.4 to $225{\mu}g/dL$(mean $93.88{\mu}g/dL$) ; serum cortisol 11.9 to $47.5{\mu}g/dL$(mean $27.49{\mu}g/dL$) ; 24-hour urine free cortisol 235 to $1019{\mu}g/day$(mean $571.0{\mu}g/day$). Inferior petrosal sinus sampling for ACTH was performed in 11 patients and all were confirmed by Cushing's disease and we could predict the laterality of the tumor in 9 of 11 patients. We performed transsphenoidal selective adenomectomy in 5 patients, adenomectomy and subtotal hypophysectomy in 2 patients, adenomectomy and partial hypophysectomy in 9 patients, and in the remaining one patient, hemihypophysectomy followed by total hypophysectomy due to remission failure. Fifteen of 17 patients(88.2%) showed endocrinological remission. Glucocorticoid replacement therapy was performed in all the patients who showed remission for 1 to 24 months(mean 5.9 months), and 6 patients received steroid over 6 months. Conclusion : We conclude that the direct demonstration of a tumor in the pituitary gland by MRI is the most important and definitive diagnostic tool and the location of a mass should be confirmed with increased level of ACTH by the inferior petrosal sinus sampling. Transsphenoidal microsurgery is effective treatment modality for Cushing's disease and the immediate postoperative evaluation of the surgical resection of the tumor is very important. The patients should show hypocortisolism, decreased, subnormal serum ACTH and cortisol levels and 24-hours urine free cortisol. We performed 18 transsphenoidal microsurgery for Cushing's disease in 17 patients and 15 patients(88.2%) showed endocrinological remission.

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A Study on Mechanical Errors in Cone Beam Computed Tomography(CBCT) System (콘빔 전산화단층촬영(CBCT) 시스템에서 기계적 오류에 관한 연구)

  • Lee, Yi-Seong;Yoo, Eun-Jeong;Kim, Seung-Keun;Choi, Kyoung-Sik;Lee, Jeong-Woo;Suh, Tae-Suk;Kim, Joeng-Koo
    • Journal of radiological science and technology
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    • v.36 no.2
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    • pp.123-129
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    • 2013
  • This study investigated the rate of setup variance by the rotating unbalance of gantry in image-guided radiation therapy. The equipments used linear accelerator(Elekta Synergy TM, UK) and a three-dimensional volume imaging mode(3D Volume View) in cone beam computed tomography(CBCT) system. 2D images obtained by rotating $360^{\circ}$and $180^{\circ}$ were reconstructed to 3D image. Catpan503 phantom and homogeneous phantom were used to measure the setup errors. Ball-bearing phantom was used to check the rotation axis of the CBCT. The volume image from CBCT using Catphan503 phantom and homogeneous phantom were analyzed and compared to images from conventional CT in the six dimensional view(X, Y, Z, Roll, Pitch, and Yaw). The variance ratio of setup error were difference in X 0.6 mm, Y 0.5 mm Z 0.5 mm when the gantry rotated $360^{\circ}$ in orthogonal coordinate. whereas rotated $180^{\circ}$, the error measured 0.9 mm, 0.2 mm, 0.3 mm in X, Y, Z respectively. In the rotating coordinates, the more increased the rotating unbalance, the more raised average ratio of setup errors. The resolution of CBCT images showed 2 level of difference in the table recommended. CBCT had a good agreement compared to each recommended values which is the mechanical safety, geometry accuracy and image quality. The rotating unbalance of gentry vary hardly in orthogonal coordinate. However, in rotating coordinate of gantry exceeded the ${\pm}1^{\circ}$ of recommended value. Therefore, when we do sophisticated radiation therapy six dimensional correction is needed.

Influence of Land Cover Map and Its Vegetation Emission Factor on Ozone Concentration Simulation (토지피복 지도와 식생 배출계수가 오존농도 모의에 미치는 영향)

  • Kyeongsu Kim;Seung-Jae Lee
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.25 no.1
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    • pp.48-59
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    • 2023
  • Ground-level ozone affects human health and plant growth. Ozone is produced by chemical reactions between oxides of nitrogen (NOx) and volatile organic compounds (VOCs) from anthropogenic and biogenic sources. In this study, two different land cover and emission factor datasets were input to the MEGAN v2.1 emission model to examine how these parameters contribute to the biogenic emissions and ozone production. Four input sensitivity scenarios (A, B, C and D) were generated from land cover and vegetation emission factors combination. The effects of BVOCs emissions by scenario were also investigated. From air quality modeling result using CAMx, maximum 1 hour ozone concentrations were estimated 62 ppb, 60 ppb, 68 ppb, 65 ppb, 55 ppb for scenarios A, B, C, D and E, respectively. For maximum 8 hour ozone concentration, 57 ppb, 56 ppb, 63 ppb, 60 ppb, and 53 ppb were estimated by scenario. The minimum difference by land cover was up to 25 ppb and by emission factor that was up to 35 ppb. From the modeling performance evaluation using ground ozone measurement over the six regions (East Seoul, West Seoul, Incheon, Namyangju, Wonju, and Daegu), the model performed well in terms of the correlation coefficient (0.6 to 0.82). For the 4 urban regions (East Seoul, West Seoul, Incheon, and Namyangju), ozone simulations were not quite sensitive to the change of BVOC emissions. For rural regions (Wonju and Daegu) , however, BVOC emission affected ozone concentration much more than previously mentioned regions, especially in case of scenario C. This implies the importance of biogenic emissions on ozone production over the sub-urban to rural regions.

Development of $^1H-^{31}P$ Animal RF Coil for pH Measurement Using a Clinical MR Scanner (임상용 MR에서 pH 측정을 위한 동물 실험용 $^1H-^{31}P$ RF 코일 개발)

  • Kim, Eun Ju;Kim, Daehong;Lee, Sangwoo;Heo, Dan;Lee, Young Han;Suh, Jin-Suck
    • Investigative Magnetic Resonance Imaging
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    • v.18 no.1
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    • pp.52-58
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    • 2014
  • Purpose : To establish a pH measurement system for a mouse tumor study using a clinical scanner, to develop the $^1H$ and 31P radio frequency (RF) coil system and to test pH accuracy with phantoms. Materials and Methods: The $^1H$ and the $^{31}P$ surface coils were designed to acquire signals from mouse tumors. Two coils were positioned orthogonally for geometric decoupling. The pH values of various pH phantoms were calculated using the $^1H$ decoupled $^{31}P$ MR spectrum with the Henderson-Hasselbalch equation. The calculated pH value was compared to that of a pH meter. Results: The mutual coil coupling was shown in a standard $S_{12}$. Coil coupling ($S_{12}$) were -73.0 and -62.3 dB respectively. The signal-to-noise ratio (SNR) obtained from the homogeneous phantom $^1H$ image was greater than 300. The high resolution in vivo mice images were acquired using a $^{31}P$-decoupled $^1H$ coil. The pH values calculated from the $^1H$-decoupled $^{31}P$ spectrum correlated well with the values measured by pH meter ($R^2$=0.97). Conclusion: Accurate pH values can be acquired using a $^1H$-decoupled $^{31}P$ RF coil with a clinical scanner. This two-surface coil system could be applied to other nuclear MRS or MRI.

Study on Optimization of Detection System of Prompt Gamma Distribution for Proton Dose Verification (양성자 선량 분포 검증을 위한 즉발감마선 분포측정 장치 최적화 연구)

  • Lee, Han Rim;Min, Chul Hee;Park, Jong Hoon;Kim, Seong Hoon;Kim, Chan Hyeong
    • Progress in Medical Physics
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    • v.23 no.3
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    • pp.162-168
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    • 2012
  • In proton therapy, in vivo dose verification is one of the most important parts to fully utilize characteristics of proton dose distribution concentrating high dose with steep gradient and guarantee the patient safety. Currently, in order to image the proton dose distribution, a prompt gamma distribution detection system, which consists of an array of multiple CsI(Tl) scintillation detectors in the vertical direction, a collimator, and a multi-channel DAQ system is under development. In the present study, the optimal design of prompt gamma distribution detection system was studied by Monte Carlo simulations using the MCNPX code. For effective measurement of high-energy prompt gammas with enough imaging resolution, the dimensions of the CsI(Tl) scintillator was determined to be $6{\times}6{\times}50mm^3$. In order to maximize the detection efficiency for prompt gammas while minimizing the contribution of background gammas generated by neutron captures, the hole size and the length of the collimator were optimized as $6{\times}6mm^2$ and 150 mm, respectively. Finally, the performance of the detection system optimized in the present study was predicted by Monte Carlo simulations for a 150 MeV proton beam. Our result shows that the detection system in the optimal dimensions can effectively measure the 2D prompt gamma distribution and determine the beam range within 1 mm errors for 150 MeV proton beam.

Radiologic Equipment and Technicians according to the Distribution of the Population (인구 분포에 따른 방사선 장비 및 종사자에 관한 고찰)

  • Yoon, Chul-Ho;Choi, Jun-Gu
    • The Journal of Korean Society for Radiation Therapy
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    • v.21 no.2
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    • pp.57-65
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    • 2009
  • Purpose: The purpose of this paper is to provide basic data in order to systemize the management of demand and supply of radiologic technicians, to pursue a fair regional distribution of educational institutions, and furthermore to keep reasonable medical treatment and fee. This research was carried out through the investigation of radiologic equipments and technicians according to the distribution of the population. Materials and Methods: We compared and analyzed the correlation between regional population, the number of clinics and hospitals, the number of medical imaging devices, and the number of radiologists and radiologic technicians in 5 cities without "Gu" administrative units in 2008. Results: 27,317 radiologic technicians have been produced since the administration of the national qualifying exam for radiologic technicians. About 18,000 radiologic technicians are currently working. There are 39 colleges or universities with Departments of Radiology and the admission quota is 2,120 students excluding one college. The ratio of radiologic equipments to radiologic technicians is 2.6 to 1. Conclusion: There is a dilemma in which some radiologic technicians fail to find appropriate jobs while some clinics or hospitals are in need of radiologic technicians. This dilemma is due to unreasonable regional discrepancies in pay system and welfare situation, and excessive profit-oriented recruiting system of clinics and hospitals. The increase of students of Radiologic Departments and approval of additional departments will end up with producing superfluous high academic degree holders, which is on the contrary to the government policy to produce more job opportunities. So the policy of increasing Radiologic Departments should be reconsidered.

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Soft-template Synthesis of Magnetically Separable Mesoporous Carbon (자성에 의해 분리 가능한 메조포러스 카본의 소프트 주형 합성)

  • Park, Sung Soo;Ha, Chang-Sik
    • Journal of Adhesion and Interface
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    • v.18 no.2
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    • pp.75-81
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    • 2017
  • In this study, we synthesized mesoporous carbon (Carbonized Ni-FDU-15) containing nanoporous structures and magnetic nanoparticles. Carbonized Ni-FDU-15 was synthesized via evaporation-induced self-assembly (EISA) and direct carbonization by using a triblock copolymer (F127) as a structure-directing agent, a resol precursor as a carbon-pore wall forming material, and nickel (II) nitrate as a metal ion source. The mesoporous carbon has a well-ordered two-dimensional hexagonal structure. Meanwhile, nickel (Ni) metal and nickel oxide (NiO) were produced in the magnetic nanoparticles in the pore wall. The size of the nanoparticles was about 37 nm. The surface area, pore size and pore volume of Carbonized Ni-FDU-15 were $558m^2g^{-1}$, $22.5{\AA}$ and $0.5cm^3g^{-1}$, respectively. Carbonized Ni-FDU-15 was found to move in the direction of magnetic force when magnetic force was externally applied. The magnetic nanoparticle-bearing mesoporous carbons are expected to have high applicability in a wide variety of applications such as adsorption/separation, magnetic storage media, ferrofluid, magnetic resonance imaging (MRI) and drug targeting, etc.

A Study on the Density Analysis of Multi-objects Using Drone Imaging (드론 영상을 활용한 다중객체의 밀집도 분석 연구)

  • WonSeok Jang;HyunSu Kim;JinMan Park;MiSeon Han;SeongChae Baek;JeJin Park
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.23 no.2
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    • pp.69-78
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    • 2024
  • Recently, the use of CCTV to prevent crowd accidents has been promoted, but research is needed to compensate for the spatial limitations of CCTV. In this study, pedestrian density was measured using drone footage, and based on a review of existing literature, a threshold of 6.7 people/m2 was selected as the cutoff risk level for crowd accidents. In addition, we conducted a preliminary study to determine drone parameters and found that the pedestrian recognition rate was high at a drone altitude of 20 meters and an angle of 60°. Based on a previous study, we selected a target area with a high concentration of pedestrians and measured pedestrian density, which was found to be 0.27~0.30 per m2. The study shows it is possible to measure risk levels by determining pedestrian densities in target areas using drone images. We believe drone surveillance will be utilized for crowd safety management in the near future.