• Title/Summary/Keyword: 2D planar

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F-18-FDG Whole Body Scan using Gamma Camera equipped with Ultra High Energy Collimator in Cancer Patients: Comparison with FDG Coincidence PET (종양 환자에서 초고에너지(511 keV) 조준기를 이용한 전신 F-18-FDG 평면 영상: Coincidence 감마카메라 단층 촬영 영상과의 비교)

  • Pai, Moon-Sun;Park, Chan-H.;Joh, Chul-Woo;Yoon, Seok-Nam;Yang, Seung-Dae;Lim, Sang-Moo
    • The Korean Journal of Nuclear Medicine
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    • v.33 no.1
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    • pp.65-75
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    • 1999
  • Purpose: The aim of this study is to demonstrate the feasibility of 2-[fluorine-18] fluoro-2-deoxy-D-glucose (F-18-FDG) whole body scan (FDG W/B Scan) using dual-head gamma camera equipped with ultra high energy collimator in patients with various cancers, and compare the results with those of coincidence imaging. Materials and Methods: Phantom studies of planar imaging with ultra high energy and coincidence tomography (FDG CoDe PET) were performed. Fourteen patients with known or suspected malignancy were examined. F-18-FDG whole body scan was performed using dual-head gamma camera with high energy (511 keV) collimators and regional FDG CoDe PET immediately followed it Radiological, clinical follow up and histologic results were correlated with F-18-FDG findings. Results: Planar phantom study showed 13.1 mm spatial resolution at 10 cm with a sensitivity of 2638 cpm/MBq/ml. In coincidence PET, spatial resolution was 7.49 mm and sensitivity was 5351 cpm/MBq/ml. Eight out of 14 patients showed hypermetabolic sites in primary or metastatic tumors in FDG CoDe PET. The lesions showing no hypermetabolic uptake of FDG in both methods were all less than 1 cm except one lesion of 2 cm sized metastatic lymph node. The metastatic lymph nodes of positive FDG uptake were more than 1.5 cm in size or conglomerated lesions of lymph nodes less than 1cm in size. FDG W/B scan showed similar results but had additional false positive and false negative cases. FDG W/B scan could not visualize liver metastasis in one case that showed multiple metastatic sites in FDG CoDe PET. Conclusion: FDG W/B scan with specially designed collimators depicted some cancers and their metastatic sites, although it had a limitation in image quality compared to that of FDG CoDe PET. This study suggests that F-18-FDG positron imaging using dual-head gamma camera is feasible in oncology and helpful if it should be more available by regional distribution of FDG.

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Structure of Z-1-Ethyl-2-Nitro-1-Butenyl-(4'-Methyl)-Phenyl Sulfone (Z-1-에칠-2-니트로-1-부텐일-(4'-메칠)-페닐 술폰의 구조)

  • Choong Tai Ahn;Gene B. Carpenter\;Kyong Bae Park
    • Journal of the Korean Chemical Society
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    • v.37 no.3
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    • pp.351-354
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    • 1993
  • Z-1-Ethyl-2-nitro-l-butenyl-(4'-methyl)-phenyl sulfone, C$_{13}$H$_{17}$NO$_4$S, Mr = 293.4, monoclinic space group P2$_1$/c, a = 12.194(7), b = 7.290(4), c = 16.532(14)${\AA}$, ${\beta}$ = 103.4(2)$^{\circ}$, V = 1429.5 ${\AA}^3$, Z = 4, D$_c$ = 1.32 gcm$^{-3}$, ${\lambda}$(Mo K${\alpha}$) = 0.71069 ${\AA}$, ${\mu}$ = 2.2 cm$^{-1}$, F(000) = 600, T = 298 K, R = 0.030 for 1762 unique observed reflections with I > 1.0${\sigma}$(I). A molecule has a cis-typed molecular structure having the form of "the substituted butene backbone, C-C(S)=C(NO$_2$)-C, connecting to a sulfur atom with the methylbenzene ring and to a nitro group. The methylbenzene ring and the substituted butene moiety are nearly planar with the maximum deviations from their own molecular planes, 0.018 ${\AA}$ for the C(1) atom of the benzene group and 0.045 ${\AA}$ for the N atom of the NO$_2$ group, respectively. The angles to the plane of the butene backbone are 88.5$^{\circ}$from the plane of the methyl-benzene and 78.6$^{\circ}$from the plane of the nitro group. Rotation of the nitro group from the butene plane seems to reduced contribution of resonance structure involving the nitro group, and resultant repulsion between the O(2) atom of SO$_2$ and the O(3) atom of NO$_2$ appears to be 2.894 ${\AA}$ longer than an expected van der Waals distance of 2.80 ${\AA}$.

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Efficacy and Accuracy of Patient Specific Customize Bolus Using a 3-Dimensional Printer for Electron Beam Therapy (전자선 빔 치료 시 삼차원프린터를 이용하여 제작한 환자맞춤형 볼루스의 유용성 및 선량 정확도 평가)

  • Choi, Woo Keun;Chun, Jun Chul;Ju, Sang Gyu;Min, Byung Jun;Park, Su Yeon;Nam, Hee Rim;Hong, Chae-Seon;Kim, MinKyu;Koo, Bum Yong;Lim, Do Hoon
    • Progress in Medical Physics
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    • v.27 no.2
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    • pp.64-71
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    • 2016
  • We develop a manufacture procedure for the production of a patient specific customized bolus (PSCB) using a 3D printer (3DP). The dosimetric accuracy of the 3D-PSCB is evaluated for electron beam therapy. In order to cover the required planning target volume (PTV), we select the proper electron beam energy and the field size through initial dose calculation using a treatment planning system. The PSCB is delineated based on the initial dose distribution. The dose calculation is repeated after applying the PSCB. We iteratively fine-tune the PSCB shape until the plan quality is sufficient to meet the required clinical criteria. Then the contour data of the PSCB is transferred to an in-house conversion software through the DICOMRT protocol. This contour data is converted into the 3DP data format, STereoLithography data format and then printed using a 3DP. Two virtual patients, having concave and convex shapes, were generated with a virtual PTV and an organ at risk (OAR). Then, two corresponding electron treatment plans with and without a PSCB were generated to evaluate the dosimetric effect of the PSCB. The dosimetric characteristics and dose volume histograms for the PTV and OAR are compared in both plans. Film dosimetry is performed to verify the dosimetric accuracy of the 3D-PSCB. The calculated planar dose distribution is compared to that measured using film dosimetry taken from the beam central axis. We compare the percent depth dose curve and gamma analysis (the dose difference is 3%, and the distance to agreement is 3 mm) results. No significant difference in the PTV dose is observed in the plan with the PSCB compared to that without the PSCB. The maximum, minimum, and mean doses of the OAR in the plan with the PSCB were significantly reduced by 9.7%, 36.6%, and 28.3%, respectively, compared to those in the plan without the PSCB. By applying the PSCB, the OAR volumes receiving 90% and 80% of the prescribed dose were reduced from $14.40cm^3$ to $0.1cm^3$ and from $42.6cm^3$ to $3.7cm^3$, respectively, in comparison to that without using the PSCB. The gamma pass rates of the concave and convex plans were 95% and 98%, respectively. A new procedure of the fabrication of a PSCB is developed using a 3DP. We confirm the usefulness and dosimetric accuracy of the 3D-PSCB for the clinical use. Thus, rapidly advancing 3DP technology is able to ease and expand clinical implementation of the PSCB.

Synthesis and Crystal Structure of Ag4Br4 Nanoclusters in the Sodalite Cavities of Fully K+-Exchanged Zeolite A (LTA)

  • Lim, Woo-Taik;Choi, Sik-Young;Kim, Bok-Jo;Kim, Chang-Min;Lee, In-Su;Kim, Seok-Han;Heo, Nam-Ho
    • Bulletin of the Korean Chemical Society
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    • v.26 no.7
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    • pp.1090-1096
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    • 2005
  • $Ag_4Br_4$ nanoclusters have been synthesized in about 75% of the sodalite cavities of fully $K^+$-exchanged zeolite A (LTA). An additional KBr molecule is retained in each large cavity as part of a near square-planar $K_4Br^{3+}$ cation. A single crystal of $Ag_{12}$-A, prepared by the dynamic ion-exchange of $Na_{12}$-A with aqueous 0.05 M $AgNO_3$ and washed with $CH_3OH$, was placed in a stream of flowing 0.05 M KBr in $CH_3OH$ for two days. The crystal structure of the product ($K_9(K_4Br)Si_{12}Al_{12}O_{48}{\cdot}0.75Ag_4Br_4$, a = 12.186(1) $\AA$) was determined at 294 K by single-crystal X-ray diffraction in the space group Pm m. It was refined with all measured reflections to the final error index $R_1$ = 0.080 for the 99 reflections for which $F_o\;{\gt}\;4_{\sigma}\;(F_o)$. The thirteen $K^+$ ions per unit cell are found at three crystallographically distinct positions: eight $K^+$ ions in the large cavity fill the six-ring site, three $K^+$ ions fill the eight-rings, and two $K^+$ ions are opposite four-rings in the large cavity. One bromide ion per unit cell lies opposite a four-ring in the large cavity, held there by two eight-ring and two six-ring $K^+$ ions ($K_4Br^{3+}$). Three $Ag^+$ and three $Br^-$ions per unit cell are found on 3-fold axes in the sodalite unit, indicating the formation of nano-sized $Ag_4Br_4$ clusters (interpenetrating tetrahedra; symmetry $T_d$; diameter ca. 7.9 $\AA$) in 75% of the sodalite units. Each cluster (Ag-Br = 2.93(3) $\AA$) is held in place by the coordination of its four $Ag^+$ ions to the zeolite framework (each $Ag^+$ cation is 2.52(3) $\AA$ from three six-ring oxygens) and by the coordination of its four $Br^-$ ions to $K^+$ ions through six-rings (Br-K = 3.00(4) $\AA$).

Low Frequency Fluctuation Component Analysis in Active Stimulation fMRI Paradigm (활성자극 파라다임 fMRI에서 저주파요동 성분분석)

  • Na, Sung-Min;Park, Hyun-Jung;Chang, Yong-Min
    • Investigative Magnetic Resonance Imaging
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    • v.14 no.2
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    • pp.115-120
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    • 2010
  • Purpose : To separate and evaluate the low frequency spontaneous fluctuation BOLD signals from the functional magnetic resonance imaging data using sensorimotor active task. Materials and Methods : Twenty female archery players and twenty three control subjects were included in this study. Finger-tapping task consisted of three cycles of right finger tapping, with a subsequent 30 second rest. Blood oxygenation level-dependent (BOLD) data were collected using $T2^*$-weighted echo planar imaging at a 3.0 T scanner. A 3-D FSPGR T1-weighted images were used for structural reference. Image processing and statistical analyses were performed using SPM5 for active finger-tapping task and GIFT program was used for statistical analyses of low frequency spontaneous fluctuation BOLD signal. Results : Both groups showed the activation in the left primary motor cortex and supplemental motor area and in the right cerebellum for right finger-tapping task. ICA analysis using GIFT revealed independent components corresponding to contralateral and ipsilateral sensorimotor network and cognitive-related neural network. Conclusion : The current study demonstrated that the low frequency spontaneous fluctuation BOLD signals can be separated from the fMRI data using finger tapping paradigm. Also, it was found that these independent components correspond to spontaneous and coherent neural activity in the primary sensorimotor network and in the motor-cognitive network.

Characteristics and Distribution Pattern of Carbonate Rock Resources in Kangwon Area: The Gabsan Formation around the Mt. Gachang Area, Chungbuk, Korea (강원 지역에 분포하는 석회석 자원의 특성과 부존환경: 충북 가창산 지역의 갑산층을 중심으로)

  • Park, Soo-In;Lee, Hee-Kwon;Lee, Sang-Hun
    • Journal of the Korean earth science society
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    • v.21 no.4
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    • pp.437-448
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    • 2000
  • The Middle Carboniferous Gabsan Formation is distributed in the Cheongrim area of southern Yeongwol and the Mt. Gachang area of Chungbuk Province. This study was carried out to investigate the lithological characters and geochemical composition of the limestones and to find out controlling structures of the limestones of the formation. The limestones of the Gabsan Formation are characterized by the light gray to light brown in color and fine and dense textures. The limestone grains are composed of crinoid fragments, small foraminfers, fusulinids, gastropods, ostracods, etc. Due to the recrystallization, some limestones consist of fine crystalline calcites. The chemical analysis of limestones of the formation was conducted to find out the contents of CaO, MgO, Al$_2$O$_3$, Fe$_2$O$_3$ and SiO$_2$. The content of CaO ranges from 49.78-60.63% and the content of MgO ranges from 0.74 to 4.63% The contents of Al$_2$O$_3$ and Fe$_2$O$_3$ are 0.02-0.55% and 0.02${\sim}$0.84% , respectively. The content of SiO$_2$ varies from 1.55 to 4.80%, but some samples contain more than 6.0%. The limestones of the formation can be grouped into two according to the CaO content: One is a group of which CaO content ranges from 49.78 to 56.26% and the other is a group of which CaO content varies from 59.36 to 60.38%. In the first group, the contents of Al$_2$O$_3$, Fe$_2$O$_3$ and SiO$_2$ range very irregularly according to the CaO content. In the second group, the values of MgO, Al$_2$O$_3$, Fe$_2$O$_3$ and SiO$_2$ are nearly same. Detailed structural analysis of mesoscopic structures and microstructures indicates the five phase of deformation in the study area. The first phase of deformation(D$_1$) is characterized by regional scale isoclinal folds, and bedding parallel S$_1$ axial plane foliation which is locally developed in the mudstone and sandstone. Based on the observations of microstructures, S$_1$ foliations appear to be developed by grain preferred orientation accompanying pressure-solution. During second phase of deformation, outcrop scale E-W trending folds with associated foliations and lineations are developed. Microstructural observations indicate that crenulation foliations were formed by pressure-solution, grain boundary sliding and grain rotation. NNW and SSE trending outcrop scale folds, axial plane foliations, crenulation foliations, crenulation lineations, intersection lineations are developed during the third phase of deformation. On the microscale F$_3$ fold, axial plane foliations which are formed by pressure solution are well developed. Fourth phase of deformation is characterized by map scale NNW trending folds. The pre-existing planar and linear structures are reoriented by F$_4$ folds. Fifth phase of deformation developed joints and faults. The distribution pattern of the limestones is mostly controlled by F$_1$ and F$_4$ folds.

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Differential Diagnosis of Metastatic Bone Disease and Benign Bone Disease on Spine SPECT in Patients with Low Back Pain (요통 환자의 척추골 SPECT에서 골전이 병변과 양성골질환의 섭취 양상 분석을 통한 감별진단이 가능한가)

  • Lee, Seung-Hun;Choi, Yun-Young;Cho, Suk-Shin
    • The Korean Journal of Nuclear Medicine
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    • v.35 no.6
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    • pp.371-377
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    • 2001
  • Purpose: One or more abnormal vertebrae detected on bone scintigraphy is a common finding in clinical practice, and it could pose a diagnostic dilemma especially in cancer patients. as either metastasis or benign disease may cause scintigraphic abnormality. The purpose of this study was to determine whether additional spine SPECT has a role in differentiating malignant from benign lesions in patients with back pain. Materials and Methods: We reviewed spine SPECT studios obtained over a three-year period in 108 patients. Among them, forty-five patients with abnormal SPECT and clinically followed records were evaluated (20 cancer patients were included). Uptake patterns were classified as follows: 1. Body: diffusely increased uptake, linear increased uptake of end plate, segmental increased uptake, and cold defect, 2. Posterior element: posterior to body (pedicle), posterior to Intervertebral disc space (facet joint), and spinous process. Lesions were correlated with radiological findings and with final diagnosis. Results: Sixty-nine bone lesions were detected on SFECT images, including 18 metastases, 28 degenerative diseases and 21 compression fractures. Cold defect (6) and segmental increased uptake (5) were dominant findings in metastasis; linear increased uptake (12), and facet joint uptake (15) were in degenerative change; and diffuse increased uptake (9), and linear increased uptake (9) were in compression fracture. Conclusion: Cold defect and segmental increased uptake of body were characteristic findings of metastasis, but care should be taken because compression fracture also shows segmental increased uptake in some cases. Degenerative disease was easily diagnosed because of the typical finding of linear increased uptake of end plate and facet joint. Therefore, additional bone SPECT after planar bone scan would be helpful for differentiating metastasis from benign condition in cancer patients.

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