• Journal of the Korean Society of Radiology
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• v.8 no.5
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• pp.271-278
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• 2014

The purpose of this study is to know optimized fat suppression techniques for brachial plexus compared with STIR and SPAIR T1, T2 techniques. A total of 30 normal volunteers without brachial plexus disease were studied on a 3.0 T MRI scanner. As an analytical method, SNR, CNR, 4-point grading scale were evaluated by using three pulse sequences. As a quantitative analysis, the SNR, CNR for SPAIR T1 technique provided high value in branchial plexus roots (03.07, -2.25), branchial plexus trunks(06.70, 36.31)(p<0.05). As a qualitative Analysis, The visibility for delineation of brachial plexus, fat suppression, artifact was significantly better on SPAIR T1(3.2, 3.6, 3.4) technique(p<0.05).

• Investigative Magnetic Resonance Imaging
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• v.3 no.1
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• pp.47-52
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• 1999

Purpose : The purpose of this study was aimed to evaluate the BOLD(blood oxygen level dependent) contrast fMRI(functional MR imaging) in the occipital lobe and to compare with the metabolic changes based on H MRS (MR spectroscopy) and MRSI (MR spectroscopic imaging) before and after visual stimulation Materials and Methods : Healthy human volunteers (eight males and two females with 24-30 year age) participated in this study. All of the BOLD fMRI were acquired on a 1.5T MR with EPI during supervised visual stimulation in the occipital lobe. The red flicker with 8Hz was used for visual stimulation. After imaging acquisition, the MR images were transferred into unix workstation and processed with acquired from the same location based on the activation map. MRSI (magnetic resonance spectroscopic imaging) was also acquired to analyze the lactate changes before and after stimulation. Results : The activation maps were successfully produced by BOLD effect due to visual stimulation. NAA (N-acetyle aspartate)/Cr (creatine) ratio varied only from $1.79{\pm}0.28{\;}to{\;}1.88{\pm}0.20$ in activation area before and after stimulation. However, the signal intensity of lactate was elevated $9.48{\pm}4.38$ times higher than before activation. Lactate metabolite images were consistent with the activation maps. Conclusion : The BOLD contrast fMRI is enough sensitive to detect the activated area in human brain during the visual stimulation. Lactate metabolite map presents the evidence of lactate elevation on the same area of activation.

• Progress in Medical Physics
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• v.23 no.3
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• pp.177-187
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• 2012

Magnetic resonance angiography (MRA) techniques are widely used in diagnosis of vascular disorders such as hemadostenosis and aneurism. Especially, phase contrast (PC) MRA technique, which is a typical non contrast-enhanced MRA technique, provides not only the anatomy of blood vessels but also flow velocity. In this study, we developed the 2- and 3-dimensional PC MRA pulse sequences for a low magnetic field MRI system. Vessel images were acquired using 2D and 3D PC MRA and the velocities of the blood flow were measured in the superior sagittal sinus, straight sinus and the confluence of the two. The 2D PC MRA provided the good quality of vascular images for large vessels but the poor quality for small ones. Although 3D PC MRA gave more improved visualization of small vessels than 2D PC MRA, the image quality was not enough to be used for diagnosis of the small vessels due to the low SNR and field homogeneity of the low field MRI system. The measured blood velocities were $25.46{\pm}0.73cm/sec$, $24.02{\pm}0.34cm/sec$ and $26.15{\pm}1.50cm/sec$ in the superior sagittal sinus, straight sinus and the confluence of the two, respectively, which showed good agreement with the previous experimental values. Thus, the developed PC MRA technique for low field MRI system is expected to provide the useful velocity information to diagnose the large brain vessels.

• The Journal of the Korea Contents Association
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• v.16 no.11
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• pp.623-632
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• 2016

The purpose of the present study was to evaluate the effect of an offered blanket on the anxiety of patients undergoing brain MRI. The participants were 52 patients who underwent brain MRI in C university hospital of G city. Blanket was applied to the experimental group (n=26) before MRI. Data were collected from May to December 2015, and analysed using the chi-squared test, the independent t-test, and repeated measures ANOVA. The results showed that there was no significant difference in the anxiety measured by STAI of the two groups. But, the level of anxiety measured by the visual analog scales was reduced in the experimental group (t=-2.75, p=0.008). There were no difference in the blood pressure and pulse rate in the experimental and control groups. Therefore, further study is needed to decrease the level of anxiety of patients undergoing brain MRI.

• Journal of Korean Medicine Rehabilitation
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• v.19 no.3
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• pp.81-90
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• 2009

Objectives : To analyze the therapeutic outcomes of back pain modalities in patients with disc herniation according to the change of Magnetic Resonanse Imaging(MRI) whom were treated with herbal medicine, chuna, acupuncture, bee-venom acupuncture. Methods : Clinical outcomes of 35 patients diagnosed with lumbar disc herniation by MRI examination, treated conservatively, were analyzed according to MRI follow-up change. Patients underwent MRI examaintion at baseline and after 24th week of treatment. Patients are divided into three groups ; improved, unchanged, worsened. 35 patients with lumbar disc herniation were treated with chuna therapy, acupuncture, bee-venom acupuncture once a week and took herbal medicine after a meal two times daily. The patients' clinical outcomes were assessed at baseline, 12th week, 24th week by Visual analogue scale(VAS), Oswestry disability index(ODI). Results : 1. MRI follow-up exams on regression of disc herniation resulted on 42.86% of cases by conservative treatment. 2. VAS(low back pain and sciatica) and ODI of disability of daily activities showed significant decrease in "improved" and "unchanged" groups compared to "worsened" group(P<0.05). 3. VAS(low back pain and sciatica) and ODI change after treatment did not show any relationship with MRI follow-up change(P<0.05). Conclusions : This study suggests that "improved" and "unchanged" groups compared to "worsened" group on MRI follow-up in patients with lumbar disc herniation were more effective when treated with herbal medicine, chuna therapy, acupuncture, bee-venom acupuncture. MRI follow-up change does not affect clinical changes in patients with lumbar disc herniation.

• Korean Journal of Adult Nursing
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• v.20 no.6
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• pp.950-959
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• 2008

Purpose: The present study was conducted in order to examine claustrophobia, noise sensitivity and vital signs according to anxiety sensitivity level in patients who have Magnet Resonance Imaging(MRI). Methods: With 100 outpatients, we measured anxiety sensitivity, claustrophobia, noise sensitivity and vital sign before and after MRI. Measuring tools were ASI, CLQ-M, and NSI. Data were collected from February to March, 2008. Results: The ASI score was higher in women than in men(p < .05), and no statistically significant difference was observed according to age, region of scanning, experience in MRI, and the use of contrast agent. Both men and women patients showed the same ASI score and decrease in CLQ M and NSI between before and after MRI. In women, ASI, CLQ M and NSI were in positive correlation with one another(p < .001), and in men, there was no correlation between ASI and CLQ M, and positive correlation was observed with NSI(p < .05). In comparison according to ASI level, blood pressure and pulse rate were not different in men and women. CLQ M was not different in men, but was different in women(p < .001). NSI was different in both men and women(men p < .05; women p < .001). Conclusion: MRI may cause claustrophobia in patients with high anxiety sensitivity, and noise appears to aggravate anxiety. In particular, claustrophobia was more serious in women than in men. Therefore, it is necessary to develop nursing interventions to reduce anxiety sensitivity particularly for female patients, and to make plans to educate and lower noise before MRI in order to reduce claustrophobia.

• The Korean Journal of Nuclear Medicine
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• v.28 no.3
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• pp.301-306
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• 1994

The purpose of this study was to compare Tc-99m-HMPAO SPECT with MRI after acute and subacute closed-head injury. There were thirty two focal lesions in all cases of these. Fifteen lesions(47%) were seen on both MRI and SPECT. Fourteen lesions(44%) were seen only on MRI. Three lesions(9%) were seen only on SPECT. Of the 14 lesions seen only on MRI, one was epidural hematoma, two were subdural hematoma, three were subdural hygroma, one was intracerebral hematoma, four were contusion, and three were diffuse axonal injuries. SPECT detected 52% of the focal lesions found on MRI. For the detection of lesions, MRI was superior to SPECT in fourteen cases, while SPECT was superior to MRI in three cases. In conclusion, there was a tendency that detection rate of the traumatic lesions was higher on MRI, but the SPECT could delineate more wide extent of lesion.

• Advances in pediatric surgery
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• v.18 no.1
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• pp.12-17
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• 2012

The purpose of this study is to analyse clinical impact of specific MRI findings in liver in patients of long-term survivors after Kasai portoenterostomy (KPE). Twenty-eight patients who were underwent KPE were followed up more than 5 years. Macro-regenerative nodule (MRN) and beaded-duct dilatation (BDD) were considered as important findings in liver MRI. The association between these findings in MRI and clinical indicator, serum bilirubin level and history of cholangitis were evaluated. Sixteen patients (57.1%) were shown MRN in liver MRI. Therewere 14 patients(50%) whose MRI showed BDD. Serum total and direct bilirubin were 3.6 mg/dL and 1.8 mg/dL respectively in positive MRN group whereas 1.4 mg/dL and 0.7 mg/dL in negative MRN group (p = 0.427). Serum total and direct bilirubin level were 4.2 mg/dL and 2.1 mg/dL in patients with BDD negative group compare to 1.1 mg/dL and 0.5 mg/dL in BDD positive group (p = 0.281). The odds ratio to have cholangitis in the patient with MRN was 2.3 and 0.53 in patient with BDD in their MRI findings. MRN in liver MRI may suggest high bilirubin level and more chance to have cholangitis, but the findings of BDD may related to low bilirubin level and less change to have cholangitis.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.11
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• pp.2077-2082
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• 2008

Recent the advanced technologies in medical imaging such as magnetic resonance imaging (MRI) and computed tomography (CT) make doctors improve the diagnostic skill with detailed anatomical information. In general, it is necessary to get a number of MRI images in order to obtain more detail information. However, the performance of MRI machines of privately run hospitals is not good and thus we may obtain only a few of MRI images. If 3D surface reconstruction is accomplished with a few slices, then it generates 3D surface of poor qualify. This paper propose a way to Set a 3D surface of high quality from a few of number of slices. First of all, our algorithm detects the boundary of tissues which we want to reconstruct as a 3D object and find out the set of vortices on the boundary. And then we generate a 3D implicit surface to interpolate the boundary points by using radial basis function. Lastly, we render the 3D implicit surface by using Marching cube algorithms.

• Journal of radiological science and technology
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• v.44 no.6
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• pp.635-643
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• 2021

The results of empirical researches on the diagnosis of lung cancer are insufficient, so it is limited to objectively judge the clinical possibility and utilization according to the accuracy of diagnosis. Thus, this study retrospectively analyzed the lung cancer diagnostic performance of PET-MRI (Positron Emission Tomography-Magnetic Resonance Imaging) by using the decision matrix. This study selected and experimented total 165 patients who received both hematological CEA (Carcinoembryonic Antigen) test and hybrid PET-MRI (¹⁸F-FDG, 5.18 MBq/kg / Body TIM coil. VIVE-Dixon). After setting up the result of CEA (positive:>4 ㎍/ℓ. negative:<2.5㎍/ℓ) as golden data, the lung cancer was found in the image of PET-MRI, and then the SUV_max (positive:>4, negative:<1.5) was measured, and then evaluated the correlation and significance of results of relative diagnostic performance of PET-MRI compared to CEA through the statistical verification (t-test, P>0.05). Through this, the PET-MRI was analyzed as 96.29% of sensitivity, 95.23% of specificity, 3.70% of false negative rate, 4.76% of false positive rate, and 95.75% of accuracy. The false negative rate was 1.06% lower than the false positive rate. The PET-MRI that significant accuracy of diagnosis through high sensitivity and specificity, and low false negative rate and false positive rate of lung cancer, could acquire the fusion image of specialized soft tissue by combining the radio-pharmaceuticals with various sequences, so its clinical value and usefulness are regarded as latently sufficient.