• Journal of the Korean Society of Radiology
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• v.83 no.4
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• pp.951-957
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• 2022

Meningiomas are the most common intracranial tumors. However, microcystic and angiomatous meningiomas are very rare subtypes that present unusual imaging findings. Hence, radiological diagnosis of these tumors can be challenging. We herein describe a case of mixed angiomatous and microcystic meningioma in an 81-year-old male. MRI revealed an extra-axial mass with high T2 signal intensity, measuring 1.5 cm in diameter, with multiple tiny intralesional cysts and entrapped peritumoral cyst formation. After tumor resection, a histopathological diagnosis of mixed angiomatous and microcystic meningioma was made.

• Clinics in Shoulder and Elbow
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• v.16 no.1
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• pp.1-9
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• 2013

Purpose: The purpose of this study is to analyze the correlation between the degree of torn rotator cuff as recorded by MRI and degenerative change of acromion and greater tuberosity of humerus determined by simple radiographs. Materials and Methods: Of the 518 cases included in this study, a group of 234 cases had a chronic rotator cuff tear and a control group of 284 cases had an intact rotator cuff in shoulder MRI. The degree of degenerative changes was classified according to the length of spur and morphological change of acromion and greater tuberosity through the true anteroposterior simple radiograph in supraspinatus outlet view. The degree of tear (partial-thickness or full-thickness tear) and the size of complete rotator cuff tear were analyzed according to the MRI findings of shoulder. The authors also evaluated the correlation between the degree and size of torn rotator cuff and the degenerative change of acromion and greater tuberosity. Results: There were significant differences in the size and extent of torn rotator cuff according to the age, sex and degenerative change of acromion and greater tuberosity of humerus (p<0.001). More degenerative changes of acromion and greater tuberosity in simple shoulder radiographs showed the increased degree and size of torn rotator cuff (p<0.001). In addition, the higher degree and larger size of torn rotator cuff were noted in older age subjects (p<0.001) and in the female group (p<0.001). Conclusion: More degenerative changes of acromion and greater tuberosity in simple shoulder radiographs showed the increased degree and size of torn rotator cuff. Therefore, if a high degree of degenerative change of the acromion and greater tuberosity on simple radiograph is noted, the possibility of degenerative rotator cuff tear should be considered. In addition, the age and sex could be associative factors for larger size of torn rotator cuff.

• Investigative Magnetic Resonance Imaging
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• v.3 no.2
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• pp.188-195
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• 1999

The fMRI signals are composed of many various signals. It is very difficult to find the accurate parameter for the model of fMRI signal containing only neural activity, though we may estimating the signal patterns by the modeling of several signal components. Besides the nose by the physiologic motion, the motion of object and noise of MR instruments make it more difficult to analyze signals of fMRI. Therefore, it is not easy to select an accurate reference data that can accurately reflect neural activity, and the method of an analysis of various signal patterns containing the information of neural activity is an issue of the post-processing methods for fMRI. In the present study, fMRI data was analyzed with the Independent Component Analysis(ICA) method that doesn't need a priori-knowledge or reference data. ICA can be more effective over the analytic method using cross-correlation analysis and can separate the signal patterns of the signals with delayed response or motion related components. The Principal component Analysis (PCA) threshold, wavelet spatial filtering and analysis of a part of whole images can be used for the reduction of the freedom of data before ICA analysis, and these preceding analyses may be useful for a more effective analysis. As a result, ICA method will be effective for the degree of freedom of the data.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.5
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• pp.240-248
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• 2020

Over the past 20 years, brain science has developed rapidly thanks to new technologies such as functional magnetic resonance imaging (fMRI), leading to more accurate knowledge of human nature and behavioral changes. This knowledge is also actively applied in the field of management. This research aimed to gain insights into how neuroscience can be incorporated into management through the case of Midas IT Co. This construction software company has a separate organization with the purpose of studying brain science, and it makes and implements human resource management policies based on brain science. The founder Lee Hyung-woo has a humanist management philosophy, and the company's brain science research supports that philosophy. The case study method was adopted as the research method, and procedures such as interviews and direct observation, participation observation, and document information were carried out. The company's human resource management system can be explained by a brain science model called "SCARF", which combines various neuroscience discoveries. As this model suggests, the company has improved the trust and satisfaction of its members by reducing threat of status and by increasing certainty, autonomy, relationship, and fairness in the workplace, resulting in the creation of a platform for creativity, integrity, and high performance.

• Korean Journal of Cognitive Science
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• v.18 no.4
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• pp.399-415
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• 2007

Many objects are always present in a visual scene. Since the visual system has limited capacity to process multiple stimuli at a time, how to cope with this informational overload is one of the important problems to solve in visual perception. This study investigated the suppressive interactions among multiple stimuli when attention was directed to either one of the stimuli or all of them. The results indicate that suppressive interactions among multiple circles were reduced in V4 when subjects paid attention to one of the four locations, as compared to the unattended condition. However, suppressive interactions were not reduced when they paid attention to all four items as a set, in order to compute their mean size. These results suggest that whereas focused attention serves to later out irrelevant information, distributed attention provides an average representation of multiple stimuli.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.4
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• pp.330-335
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• 2002

The study was performed to investigate the comparison of relative signal intensity of normal- and abnormal-side retrodiscal tissue, and relationship between clinical examination, joint effusion and relative signal intensity of retrodiscal tissue in patients with unilateral TMJ internal derangement. The study group comprised 19 females and 9 males, with a mean age of 29 years. After measurements of the signal intensity were made on the MR imager for the T2 weighted images on retrodiscal tissue and brain gray matter, we calculated relative value and tried to find relationship between clinical examination, joint effusion and relative signal intensity on normal- and abnormal-side. The results are as follows. 1. The gray matter is an appropriate reference point. 2. The relative signal intensity is high significantly in abnormal-side retrodiscal tissue compared with normal-side retrodiscal tissue. 3. The relative signal intensity is high significantly in painful joints compared with nonpainful joints and in joints with joint effusion compared with joints without joint effusion. 4. The relative signal intensity in normal joints, joints with reduction and joints without reduction is increased in order significantly.

• Korean Journal of Biological Psychiatry
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• v.24 no.2
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• pp.68-74
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• 2017

Objectives It is well known that problem drinking is associated with alterations of brain structures and functions. Brain functions related to alcohol consumption can be determined by the resting state functional connectivity in various resting state networks (RSNs). This study aims to ascertain the alcohol effect on the structures forming predetermined RSNs by assessing their cortical thickness. Methods Twenty-six abstinent male patients with alcohol dependence and the same number of age-matched healthy control were recruited from an inpatient mental hospital and community. All participants underwent a 3T MRI scan. Averaged cortical thickness of areas constituting 7 RSNs were determined by using FreeSurfer with Yeo atlas derived from cortical parcellation estimated by intrinsic functional connectivity. Results There were significant group differences of mean cortical thicknesses (Cohen's d, corrected p) in ventral attention (1.01, < 0.01), dorsal attention (0.93, 0.01), somatomotor (0.90, 0.01), and visual (0.88, 0.02) networks. We could not find significant group differences in the default mode network. There were also significant group differences of gray matter volumes corrected by head size across the all networks. However, there were no group differences of surface area in each network. Conclusions There are differences in degree and pattern of structural recovery after abstinence across areas forming RSNs. Considering the previous observation that group differences of functional connectivity were significant only in networks related to task-positive networks such as dorsal attention and cognitive control networks, we can explain recovery pattern of cognition and emotion related to the default mode network and the mechanisms for craving and relapse associated with task-positive networks.

• Anxiety and mood
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• v.3 no.2
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• pp.123-127
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• 2007

Objective : This study was conducted to evaluate the relation between symptoms and hippocampal volume in patients with posttraumatic stress disorder (PTSD). Methods : Eight patients with PTSD and five normal controls were enrolled in the present study. The severity of PTSD symptoms was measured using the clinician administered PTSD scale (CAPS), Hamilton Rating Scale for Depression (HAMD), Hamilton Anxiety Rating Scale (HAMA). Magnetic resonance imaging (MRI) was used to measure hippocampal volume. Results : There were significant differences in the CAPS, HAMD, and HAMA scores between the PTSD patients and normal controls. The left and right hippocampal volumes were smaller in the PTSD patients than in the normal controls, but this difference was not statistically significant. The results showed that PTSD symptoms were not related to hippocampal volume. Conclusion : In this study, we could not identify a difference in hippocampal volume between normal controls and patients with PTSD at eight months after trauma. Future research with different subjects and a larger sample size is needed in order to confirm the difference in hippocampal volume.

• Anxiety and mood
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• v.10 no.2
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• pp.143-150
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• 2014

Objective : The subgenual cingulate cortex, a part of default-mode network, has been known to playa key role in the pathophysiology of depression. The previous studies have reported abnormal functional connectivity between the subgenual cingulate cortex and other brain regions in the patients with depression. The goal of this shldy was to explore the resting-state functional connectivity of the subgenual cingulate cortex between the patients with depression and healthy subjects. Methods : Twenty patients with major depression and age- and sex-matched 20 healthy subjects underwent 5-minute resting state fMRI scans. The functional connectivity map in each subject was acquired using seed-based correlation analysis with the seed located in the subgenual cingulate cortex (Talairach coordinates; x=-10, y=5, z=-10). The functional connectivity maps were calculated using AFNI and compared between the patient and healthy subject group via two-sample T-test using 3dttest++ in AFNI package. Results : Functional connectivity was decreased between the subgenual cingulate cortex and both sides of fusiform gyrus in depressed subjects. Connectivity was also decreased between the subgenual cingulate cortex and the left cerebellum in the patient group. There was no correlation between the severity of depression and the degree of functional connectivity between the subgenual cingulate cortex and the regions showing decreased functional connectivity. Conclusion : Decreased resting-state functional connectivity between the subgenual cingulate cortex and both sides of fusiform gyrus, and decreased connectivity between the subgenual cingulate cortex and the left cerebellum found in the patients with major depression in comparison to the healthy subjects might be related to abnormal emotional and cognitive processing of depressed patients.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.15 no.3
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• pp.189-197
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• 1993

Tempormandibular Joint pain and dysfunction is a common and important clinical problem. With the recent advances in imaging technology, radiologists have made major contribution to the understanding of TMJ disease. The MRI has several advantages over the conventional imaging methods. It is possible to obtain surprisingly precise images of internal hard and soft tissues with MRI. It is not invasive without ionizing radiation. The abnormal disk position has been thought as the cause of TMJ internal derangement. But there are few methods to relate disk position to TMJ internal derangement quantatively. The object of our study is to determine the amount of anterior displacement fo articular disk in symptomatic patients related each symptoms. Using the method of Dr. Drace, we studied the 38 joints of 22 persons with susceptable TMJ internal derangement. 1. In determining the anterior displacement of TMJ articular disk, the junction between the posterior band and bilaminar zone was useful. 2. The mean anterior displacement of disk in reduction group and without reduction group were $51.0^{\circ}C$ and $81.1^{\circ}C$ respectively. The difference was significant. 3. In the mean anterior displacement of disk, the pain without clicking group showed $84.8^{\circ}C$ and the clicking and pain group $70.8^{\circ}C$, the clicking group respectively.