• Proceedings of the KSMRM Conference
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• 1999.11a
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• pp.55-56
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• 1999

• Investigative Magnetic Resonance Imaging
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• v.21 no.3
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• pp.139-147
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• 2017

Purpose: To evaluate differences in staging accuracy of prostate cancer according to the extent of hemorrhage on multiparametric MRI performed after biopsy. Materials and Methods: We enrolled 71 consecutive patients with biopsy-proven prostate cancer. Patients underwent MRI followed by a prostatectomy at our institution in 2014. Two radiologists reviewed the MRI to determine the tumor stage. Correlation between biopsy-MRI interval and extent of hemorrhage was evaluated. Regression analyses were used to determine factors associated with accuracy of tumor staging. Results: The mean interval between biopsy and MRI was $17.4{\pm}10.2days$ (range, 0-73 days). The interval between prostate biopsy and MRI and the extent of hemorrhage were not significantly correlated (P = 0.880). There was no significant difference in the accuracy rate of staging between the small and large hemorrhage groups. Conclusion: Biopsy-induced hemorrhage in the prostate gland is not sufficiently absorbed over time. The extent of hemorrhage and the short interval between biopsy and MRI may not impair tumor detection or staging on multiparametric MRI.

• Journal of Korean Neurosurgical Society
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• v.61 no.1
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• pp.97-104
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• 2018

Objective : Diffusion-weighted magnetic resonance imaging (DW-MRI) has proven useful in the study of the natural history of ischemic stroke. However, the potential of DW-MRI for the evaluation of chronic subdural hematoma (CSDH) has not been established. In this study, we investigated DW-MRI findings of CSDH and evaluated the impact of the image findings on postoperative outcomes of CSDH. Methods : We studied 131 CSDH patients who had undergone single burr hole drainage surgery. The images of the subdural hematomas on preoperative DW-MRI and computed tomography (CT) were divided into three groups based on their signal intensity and density : 1) homogeneous (iso or low) density on CT and homogeneous low signal intensity on DW-MRI; 2) homogeneous (iso or low) density on CT and mixed signal intensity on DW-MRI; and 3) heterogeneous density on CT and mixed signal intensity on DW-MRI. On the basis of postoperative CT, we also divided the patients into 3 groups of surgical outcomes according to residual hematoma and mass effect. Results : Analysis showed statistically significant differences in surgical (A to B : p<0.001, A to C : p<0.001, B to C : p=0.129) and functional (A to B : p=0.039, A to C : p<0.001, B to C : p=0.108) outcomes and treatment failure rates (A to B : p=0.037, A to C : p=0.03, B to C : p=1) between the study groups. In particular, group B and group C showed worse outcomes and higher treatment failure rates than group A. Conclusion : CSDH with homogeneous density on CT was characterized by signal intensity on DW-MRI. In CSDH patients, performing DW-MRI as well as CT helps to predict postoperative treatment failure or complications.

• 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 the Institute of Electronics Engineers of Korea SP
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• v.41 no.5
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• pp.53-62
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• 2004

In this study, an improved post-processing technique for correcting MRI artifact due to the unknown respiratory motion in the imaging plane is presented. Respiratory motion is modeled by a two-Dimensional linear expending-shrinking movement. Assuming that the body tissues are incompressible fluid like materials, the proton density per unit volume of the imaging object is kept constant. According to the introduced model, respiratory motion imposes phase error, non-uniform sampling and amplitude modulation distortions on the acquired MRI data. When the motion parameters are known or can be estimatead a reconstruction algorithm based on biliner superposition method was used to correct the MRI artifact. In the case of motion parameters are unknown, first, the spectrum shift method is applied to find the respiratory fluctuation function, x directional expansion coefficient and x directional expansion center. Next, y directional expansion coefficient and y directional expansion center are estimated by using the minimum energy method. Finally, the validity of this proposed method is shown to be effective by using the simulated motion images.

• 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.

• Journal of KIISE:Computing Practices and Letters
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• v.8 no.6
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• pp.705-716
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• 2002

This paper proposes a method which visualizes MRI head data in 3 dimensions with direct volume rendering. Though surface rendering is usually used for MRI data visualization, it has some limits of displaying little speckles because it loses the information of the speckles in the surfaces while acquiring the information. Direct volume rendering has ability of displaying little speckles, but it doesn't treat MRI data because of the data features of MRI. In this paper, we try to visualize MRI head data in 3 dimensions as follows. First, we separate the brain region from the head region of MRI head data, next increase the pixel level of the brain region, then combine the brain region with the increased pixel level and the head region without brain region, last visualizes the combined MRI head data with direct volume rendering. We segment the brain region from head region based on histogram threshold, morphology operations and snakes algorithm. The proposed segmentation method shows 91~95% similarity with a hand segmentation. The method rather clearly visualizes the organs of the head in 3 dimensions.

• 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.