• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.10
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• pp.2985-2989
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• 2009

An experiment was conducted to examine the effects of ceramic sheet on concentration of students studies. To demonstrate the improvement in the concentration of study, we obtained functional magnetic resonance imaging (fMRI), which has superior time resolution and measures brain noninvasively by using intrinsic contrast agent. As a result of Brainwave measurement, we could verify the blood flow's activate in the nearby frontal lobe related to memory process and noticeable ratio change in absolute alpha wave and beta wave after the analysis of Brainwave measurement. fMRI ascertains the physiological function of the brain and is being used to prevent the trouble medically that can be caused before and after the operation. For the visibility of cranial nerve network, many researches will be carried out to develope the product which is related to brain like concentration of study.

• Journal of the Korean Arthroscopy Society
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• v.17 no.1
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• pp.76-78
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• 2013

The meniscus is considered "extruded" when it extends beyond the tibial margins more than 3 mm in a coronal view of magnetic resonance imaging (MRI). However, identifying the meniscal extrusion intraoperatively may be difficult because of the simple fact that most of the arthroscopic procedures are done in knee flexion position while follow up MRI studies area taken at knee extension position. Here, we demonstrate the arthroscopic technique for evaluating the meniscal extrusion.

• Journal of the Korean Society of Radiology
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• v.82 no.2
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• pp.469-474
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• 2021

Japanese encephalitis (JE) is a common infection caused by the Japanese encephalitis virus in Southeast Asia, which is transmitted to humans through Culex mosquitoes. Magnetic resonance imaging (MRI) is used to diagnose JE, which is often characterized by the presence of bilateral symmetric thalamic involvement. Here, we report a rare case of JE characterized by leptomeningeal enhancement without thalamic involvement. This leptomeningeal enhancement disappeared with the treatment; however, new non-specific multifocal and bilateral high signal intensities in the cerebral white matter were found on follow-up MRI.

• The Journal of the Korea Contents Association
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• v.17 no.7
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• pp.437-442
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• 2017

Previously, studies on compensation material to increase the signal intensity have been conducted which does not affect the reading of images. However, the compensation material has a concern on patient infection as it is attached directly on the skin. Therefore, in this study, we tested an indirect attachment of the compensation material as an alternative method of the direct attachment. The silicon compensation material was fabricated in the form of a cylindrical bar and attached to each element of the 8 channel head coil. Then the signal intensities of the water phantom pre and post application of the silicon were measured. T1 and T2-weighted images were acquired using an 8-channel head coil and a 3.0T superconducting MRI. Signal intensities were measured by using an image measuring program. Paired t-test was used to verify if there were significant differences. The signal intensity before application of the silicon was significantly increased by 3.39% and 2.62% in T1 and T2 weighted images, respectively. Although the indirect attachment method had a limitation to completely replace the existing method, it was considered to be useful in patients with infectious diseases such as diabetic complications since it had a meaningful improvement in signal intensity based on the filling factor increase.

• Journal of the Korean Society of Radiology
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• v.83 no.5
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• pp.1116-1120
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• 2022

The kidney is a rare site of ectopic adrenal adenoma. To the best of our knowledge, some cases of ectopic adrenal adenoma have been found in the kidney, but few of these cases explain the CT and MRI findings of the lesion. We reported a case of ectopic adrenal adenoma in the left renal sinus. A 47-year-old male patient underwent abdominal CT for routine health check-ups, which revealed a 1.2 cm enhancing mass in the left renal sinus. The MRI showed a signal drop of the mass in T1 weighted in- and opposed-phase, which indicates fat components. The mass was confirmed as an ectopic adrenal adenoma after surgery.

• Korean Journal of Cognitive Science
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• v.21 no.1
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• pp.77-93
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• 2010

The aim of this study was to identify neural correlates underlying the detection of faux pas, a test of theory of mind (ToM), in Korean healthy adults. Using functional magnetic resonance imaging, we compared the brain activities associated with faux pas stories and the activities associated with control stories. Faux pas stories compared with the control stories produced activations bilaterally in the superior frontal gyrus (BA 9) and in the precuneus (BA 7). The left medial frontal gyrus (BA 9), the left superior temporal gyrus (BA 38), the left inferior temporal gyrus (BA 20) and the right inferior parietal lobule (BA 40), the right postcentral gyrus (BA 1), the right lingual gyrus (BA 18), the right transverse temporal gyrus (BA 41) were also activated. The orbitofrontal cortex and the amygdala were not found to be involved in the detection of faux pas. This result suggests that brain activations associated with ToM are dependent on the type of mental state drawn by the task.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.3
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• pp.103-108
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• 2016

This study examined the effectiveness of the multitransmit parallel technique on the MRI scan time reduction by removing the dielectric effect. The T1 and T2 weighted images of the patients' hip joint were acquired with and without a multitransmit technique. The ROIs were located in the head of femur and iliopsoas muscle. The SNR, CNR and scan time were measured and compared. There was no difference in the images with and without multitransmit. In contrast, the acquisition time was decreased by 42.8% in T1WI and 49.7% in T2WI. In conclusion, this study demonstrated that significant scan time reductions can be accomplished without any differences in the image quality in hip joint MRI by applying the multitransmit parallel technique. Furthermore, the multitranstmit technique is useful in other body parts to resolve the long scan time of an MRI examination.

• Journal of radiological science and technology
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• v.39 no.1
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• pp.51-57
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• 2016

Acoustic noise during magnetic resonance imaging (MRI) is the main source for patient discomfort. we report our preliminary experience with this technique in neuroimaging with regard to subjective and objective noise levels and image quality. 60 patients(29 males, 31 females, average age of 60.1) underwent routine brain MRI with 3.0 Tesla (MAGNETOM Tim Trio; Siemens, Germany) system and 12-channel head coil. Q-$T_2$ and $T_2$ sequence were performed. Measurement of sound pressure levels (SPL) and heart rate on Q-$T_2$ and $T_2$ was performed respectively. Quantitative analysis was carried out by measuring the SNR, CNR, and SIR values of Q-$T_2$, $T_2$ and a statistical analysis was performed using independent sample T-test. Qualitative analysis was evaluated by the eyes for the overall quality image of Q-$T_2$ and $T_2$. A 5-point evaluation scale was used, including excellent(5), good(4), fair(3), poor(2), and unacceptable(1). The average noise and peak noise decreased by $15dB_A$ and $10dB_A$ on $T_2$ and Q-$T_2$ test. Also, the average value of heartbeat rate was lower in Q-$T_2$ for 120 seconds in each test, but there was no statistical significance. The quantitative analysis showed that there was no significant difference between CNR and SIR, and there was a significant difference (p<0.05) as SNR had a lower average value on Q-$T_2$. According to the qualitative analysis, the overall quality image of 59 case $T_2$ and Q-$T_2$ was evaluated as excellent at 5 points, and 1 case was evaluated as good at 4 points due to a motion artifact. Q-$T_2$ is a promising technique for acoustic noise reduction and improved patient comfort.

• The Journal of the Korea Contents Association
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• v.16 no.11
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• pp.699-706
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• 2016

This study aimed to propose the necessity and system establishment of noise reduction facility via evaluating noise level exposed by the radiographer due to MRI scan. Noise measurements were carried out using at S general hospital in Daejeon using 1.5 Tesla MRI (7 exams) and 3.0 Tesla MRI (16 exams), while using SC-804 noise meter. The measurement distance was from the soundproof door of the MRI room to the radiographer which measured 100cm, and the measurement height, the height to the radiographer's ears when working, 100cm. The noise measured for each exam was an average of three measures per exam which observed the noise occurring in each sequence recorded every 20 seconds. As the results, the maximum of noise exposed by the radiographer is 73.3 dB(A), which is MRCP by the 3.0 Tesla device, and also the maximum of average noise is 66.9(3.1) dB(A), which is Myelogram by the 3.0 Tesla device. Average noise by each device is 61.9(4.1) dB(A) by the 3.0 Tesla device and 52.0(3.1) dB(A) by the 1.5 Tesla device, which comes to the result that the 3.0 Tesla MRI device is about 10 dB(A) degree higher(p <0.001). The noise level exposed by the radiographer does not affect auditory acuity, but the level is able to incur a non auditory effect. The reflect sound can be removed by installing curtains in the rear wall of MRI control room in order to reduce the noises, but, first of all, An institutional system is needed in order to prevent noise.

• Journal of the Korean Society of Radiology
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• v.84 no.4
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• pp.964-969
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• 2023

Guillain-Barré syndrome (GBS) is an immune-mediated demyelinating polyneuropathy characterized by progressive, ascending, and symmetrical paralysis. It is known to be triggered by an antecedent infection or vaccination. Recently, GBS development following coronavirus disease 2019 (COVID-19) vaccination has been reported. Cranial neuropathies in typical GBS patients usually involve the facial and the lower cranial nerves (from IX to XII). We report a rare case of multiple cranial neuropathies involving trigeminal, abducens, and facial nerves in a patient who developed GBS following COVID-19 vaccination on the basis of obvious MRI features.