• Proceedings of the KOSOMBE Conference
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• 대한의용생체공학회 1998년도 추계학술대회
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• pp.98-99
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• 1998

In this paper, an interleaved spiral scan imaging is investigated for an ultra fast MR imaging. The interleaved spiral technique has relative advantage over single shot spiral imaging with improved resolution and less inhomogeneity-related artifact. An improved reconstruction algorithm is devised with DC-offset correction. Some preliminary experimental results are shown at 1.0 Tesla and 3.0 Tesla whole body MRI system.

• Korean Journal of Applied Biomechanics
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• 제12권1호
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• pp.233-249
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• 2002

The purpose of this study was to employing MRI in the estimation of the biomechanical body segment parameters of Korean adults. for this purpose MRI study on 19 Korean living subjects were used to measurement. All the parameters that was concerned were inertial characteristics of human body mass of each segment, center of mass of them and the length of radius of gyration of them. The cross sectional images and saggital images of every 1cm interval were got using the 0.5 Tesla MRI from the top of head to the bottom of foot, whole body. And then, by tracing the images of the film and scanning them, got the area which the several tissues occupied in the image of slice. By summing the area of slice of each segment which were calculating and by multipling the density of the tissues, got the mass of segment and other inertial characteristics. The ratios of radius of gyration in both transverse axis and longitudinal axis though the segmental mass and segment length are as follow: male A : head($0.229\pm0.0029$), neck($0.256\pm0.0095$), thorax($0.374\pm0.0059$) abdomen($0.245\pm0.0020$), pelvis($0.368\pm0.0106$), thigh($0.288\pm0.0030$) shank($0.280\pm0.0043$), foot($0.277\pm0.0195$), upperarm($0.311\pm0.0074$) forearm($0.286\pm0.0051$), hand($0.253\pm0.0095$) female A : head($0.214\pm0.0032$), neck($0.254\pm0.0112$), thorax($0.295\pm0.0061$) abdomen($0.289\pm0.0021$), pelvis($0.329\pm0.0108$), thigh($0.288\pm0.0036$) shank($0.280\pm0.0047$), foot($0.243\pm0.0206$), upperarm($0.279\pm0.0083$) forearm($0.286\pm0.0048$), hand($0.229\pm0.0097$) male B : head($0.532\pm0.0006$), neck($0.533\pm0.0006$), thorax($0.658\pm0.0008$) abdomen($1.350\pm0.0022$), pelvis($0.875\pm0.0002$), thigh($0.213\pm0.0001$) shank($0.160\pm0.0001$), foot($0.152\pm0.0002$), upperarm($0.136\pm0.0002$) forearm($0.202\pm0.0002$), hand($0.273\pm0.0006$) female B : head($0.198\pm0.0002$), neck($0.335\pm0.0011$), thorax($0.238\pm0.0001$) abdomen($0.888\pm0.0001$), pelvis($1.318\pm0.0117$), thigh($0.095\pm0.0001$) shank($0.075\pm0.0001$), foot($0.181\pm0.0006$), upperarm($0.0.062\pm0.0001$) forearm($0.083\pm0.0001$), hand($0.105\pm0.0007$).

• The Korean Journal of Nuclear Medicine Technology
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• 제18권1호
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• pp.19-25
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• 2014

Purpose: Integrated PET/MRI has been developed recently has become a lot of help to the point oncologic, neological, cardiological nuclear medicine. By using this PET/MRI, a ${\mu}-map$ is created some special MRI sequence which may be divided parts of the body for attenuation correction. However, because an MRI contrast agent is necessary in order to obtain an more MRI information, we will evaluate to see an effect of SUV on PET image that corrected attenuation by MRI with contrast agent. Materials and Methods: As PET/MRI machine, Biograph mMR (Siemens, Germany) was used. For phantom test, 1mCi $^{18}F-FDG$ was injected in cylinderical uniformity phantom, and then acquire PET data about 10 minutes with VIBE-DIXON, UTE MRI sequence image for attenuation correction. T1 weighted contrast media, 4 cc DOTAREM (GUERBET, FRANCE) was injected in a same phatnom, and then PET data, MRI data were acquired by same methodes. Using this PET, non-contrast MRI and contrast MRI, it was reconstructed attenuation correction PET image, in which we evanuated the difference of SUVs. Additionally, for let a high desity of contrast media, 500 cc 2 plastic bottles were used. We injected $^{18}F-FDG$ with 5 cc DOTAREM in first bottle. At second bottle, only $^{18}F-FDG$ was injected. and then we evaluated a SUVs reconstructed by same methods. For clinical patient study, rectal caner-pancreas cancer patients were selected. we evaluated SUVs of PET image corrected attenuastion by contrast weighted MRI and non-contrast MRI. Results: For a phantom study, although VIBE DIXON MRI signal with contrast media is 433% higher than non-contrast media MRI, the signals intensity of ${\mu}-map$, attenuation corrected PET are same together. In case of high contrast media density, image distortion is appeared on ${\mu}-map$ and PET images. For clinical a patient study, VIBE DIXON MRI signal on lesion portion is increased in 495% by using DOTAREM. But there are no significant differences at ${\mu}-map$, non AC PET, AC-PET image whether using contrast media or not. In case of whole body PET/MRI study, %diff between contras and non contrast MRAC at lung, liver, renal cortex, femoral head, myocardium, bladder, muscle are -4.32%, -2.48%, -8.05%, -3.14%, 2.30%, 1.53%, 6.49% at each other. Conclusion: In integrated PET/MRI, a segmentation ${\mu}-map$ method is used for correcting attenuation of PET signal. although MRI signal for attenuation correciton change by using contrast media, ${\mu}-map$ will not change, and then MRAC PET signal will not change too. Therefore, MRI contrast media dose not affect for attenuation correction PET. As well, not only When we make a flow of PET/MRI protocol, order of PET and MRI sequence dose not matter, but It's possible to compare PET images before and after contrast agent injection.

• The Korean Journal of Nuclear Medicine
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• 제29권4호
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• pp.504-510
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• 1995

Avascular necrosis(AVN) of bone can be resulted from various causes that distrub vascular supply to bone tissue, including steroid therapy after renal transplantation. In this study, we determine the prevalence of the avascular necrosis of bone after renal transplantation and compare the role of the bone scan, SPECT and MRI. In 301 patients with transplanted kidney, the prevalence of avascular necrosis was deter-mined clinically. Site of bone necrosis was evaluated by clinical symptom, bone scan, SPECT and MRI. Bone scan was done in all patients with AVN. Bone SPECT and MRI were done in six cases; and MRI was done in two cases. The prevalence of AVN was 3.3% (10/301), and the site of AVN was 16 femoral heads in 10 patients (bilateral: 60%) and bilateral calcaneal tuberosity in one patient. Bone scan showed typical AVN (cold area with surrounding hot uptake) in 13 lesions, only hot uptake in three lesions (including two calcaneal tuberosities), decreased uptake in one lesion, and normal in one lesion. Decreased uptake and normal lesion showed an equivacal cold area without surrounding hot uptake on SPECT. A symptomatic patient with positive bone SPECT showed normal finding on MRI. The prevalence of AVN of bone after renal transplantation was 3.3%, and whole body bone scan showed multiple bone involvement. Two symptomatic hip Joints without definite lesion on whole body bone scan or MRI showed cold defect on SPECT. Therefore, we conclude that bone SPECT should be perfomed in a symptomatic patient with negative bone scan or MRI in case with high risk of AVN after renal transplantation.

• Journal of Acupuncture Research
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• 제20권5호
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• pp.133-150
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• 2003

Objective: Recently. many studies have showed the evidences of the effect of the Electro-acupuncture treatment through scientific. Methods : One of these methods is functional MRI. We performed electro-acupuncture on Zusanli(St36) and observed the change of brain activation using fMRI. Zusanli(St36) is located on the lateral side of the lower leg. 3 cun(寸) inferior to the Patella of the lower border. Theoretically and clinically. this point has been considered very important for gynecological disorders. spleen and stomach disorders. and psychological disorders. To see the effects of electro-acupuncture stimulation on Zusanli(St36). the experiment was carried out on twelve healthy volunteers. using the gradient echo sequence with the 3.0T whole-body fMRI system(ISOL). After the needle insertion on right Zusanli(St36). 2 Hz of electric stimulation was given for 30 seconds. repeated five times. with 30 seconds' intervals. The Image analysis including motion correction. talairach transformation, and smoothing was done with SPM99. Results ad conclusion : The electro-acupuncture stimulation on Zusanli(St36) activates Brodmann Area 6, 13, 2, 19, 21, 22, 39, 40, 38, 3which indicates the pathways of the electro-acupuncture stimulation on Zusanli(St36) and the possibility of the relationship of the electro-acupuncture stimulation on Zusanli(St36) with autonomic nervous system, internal organic system.

• Journal of Acupuncture Research
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• 제20권5호
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• pp.208-226
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• 2003

Objective : Recently many studies have showed the evidence of the effect of the acupuncture treatment through scientific methods. One of these methods is functional MRI. We performed electro-acupuncture on St40 and observed the change of brain activation using fMRI. Methods : To see the effects of electro-acupuncture stimulation on Fenglong(St40), the experiment was carried out on six healthy volunteers, using the gradient echo sequence with 3.0T whole-body MRI system(ISOL). after the needle insertion on right Fenglong(St40), 2 Hz of electric stimulation was given for 30 seconds, repeated five times, with 30 seconds' intervals. Results & Conclussion : Electro-acupuncture stimulation on Fenglong(St40) activated Brodmann's Areas of 2, 3, 4, 6, 9, 10, 13, 18, 22, 30, 40, 42, 43 which may be the central pathways of electro-acupuncture stimulation on Fenglong(St40).

• Journal of Acupuncture Research
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• 제20권5호
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• pp.187-207
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• 2003

Objective: Recently, many studies have showed the evidences of the effect of the acupuncture treatment through scientific methods. One of these methods is functional MRI. We performed electro-acupuncture on Liv3 and observed the change of brain activation using fMRI. Methods: To see the effect of electro-acupuncture stimulation on Liv3. the experiment was carried out on 12 healthy volunteers. using the gradient echo sequence with the 3.0T whole-body MRI system(ISOL). After the needle insertion on right Liv3. 2 Hz of electric stimulation was given for 30 seconds. repeated five times. with 30 seconds' intervals. The Image analysis including motion correction, talairach transformation. and smoothing was done with SPM99. Results : 1. Group averaged brain activation induced by bilateral electro-acupuncture stimulation on Liv3 activates Brodman Area 6, 13, 18, 19, 22, 31, 39, 44, 2. Group averaged brain deactivation induced by bilateral Electro-acupuncture stimulation on Liv3 activates Brodman Area 4, 6, 9, 19, 36, 37, 39. 3. Group averaged brain activation induced by unilateral(right side) electro-acupuncture stimulation on Liv3 activates Brodman Area 2, 3, 6, 9, 10, 22, 40, 42, 43. 4. Group averaged brain deactivation induced by unilateral(right side) electro-acupuncture stimulation on Liv3 activates Brodman Area 6, 18, 19, 28, 30, 31, 35, 37. 5. Brain region activated by motor stimulation activates Brodman Area 4, 6, 13, 19, 42.

• Journal of Acupuncture Research
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• 제20권3호
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• pp.86-103
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• 2003

Objective : Recently, many studies have showed the evidences of the effect of the acupunture treatment through scientific methods. One of these methods is functional MRI. We performed electro-acupunture on Sp6 and observed the changes of brain activation using fMRI. Methods : To see the effect of electro-acupunture stimulation on Sp6, the experiment was carried out on 12 healthy volunteers, using the gradient echo sequence with the 3.0T whole-body MRI system(ISOL). After the needle insertion on right Sp6, 2Hz of electric stimulation was given for 30 seconds, repeated five times, with 30 seconds' intervals. The Image analysis including motion correction, talairach transformation, and smoothing was done with SPM99. Results : 1. Group averaged brain activation induced by bilateral eletro-acupunture stimulation on Sp6 activates Brodman Area 3, 7, 13. 2. Group averaged brain deactivation induced by bilateral eletro-acupunture stimulation on Sp6 activates Brodman Area 6, 38, 47. 3. Group averaged brain activation induced by unilateral(right side) eletro-acupunture stimulation on Sp6 activates Brodman Area 5, 6, 13, 17, 18, 19, 31, 38, 40 ptoms, back pain(32.5%) was the 4. Group averaged brain deactivation induced by unilateral(right side) eletro-acupunture stimulation on Sp6 activates Brodman Area 3, 4, 18, 21, 36, 38, 39. 5. Brain region activated by motor stimulation activates Brodman Area 3, 4, 6, 18, 19.

• Asian Pacific Journal of Cancer Prevention
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• 제13권5호
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• pp.1713-1718
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• 2012

Advanced imaging approaches (computed tomography, CT; magnetic resonance imaging, MRI; $^{18}F$-fluorodeoxyglucose positron emission tomography, FDG PET) have increased roles in cervical cancer staging and management. The recent FIGO (International Federation of Gynecology and Obstetrics) recommendations encouraged applications to assess the clinical extension of tumors rather than relying on clinical examinations and traditional non-cross sectional investigations. MRI appears to be better than CT for primary tumors and adjacent soft tissue involvement in the pelvis. FDG-PET/CT has increased in usage with a particular benefit for whole body evaluation of tumor metabolic activity. The potential benefits of advanced imaging are assisting selection of treatment based upon actual disease extent, to adequately treat a tumor with minimal normal tissue complications, and to predict the treatment outcomes. Furthermore, sophisticated external radiation treatment and brachytherapy absolutely require advanced imaging for target localization and radiation dose calculation.

• Nuclear Medicine and Molecular Imaging
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• 제42권1호
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• pp.70-73
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• 2008

A 65 year-old man with hepatocellulcar carcinoma (HCC) admitted to treat left lower leg swelling and pus discharge suspecting osteomyelitis. MRI of his lower leg revealed the bone metastasis. Whole body FDG PET/CT additionally detected left shoulder and right ilium metastasis. Hematemesis suddenly developed in this patient after 3 weeks. Metastasis of right tonsil was histologically proven. When we reviewed his FDG PET/CT, there was asymmetric mild hypermetabolism in the right tonsil. When focal hypermetabolism is shown in the organ physiologically taking glucose up such as tonsil, we should cautiously assess whole body PET/CT in the examination of distant metastasis. We present a patient with multiple distant metastasis including tonsil from HCC showing increased FDG uptake with the literature review.