• Investigative Magnetic Resonance Imaging
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• v.24 no.3
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• pp.174-177
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• 2020

Multiple studies have established that mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) exhibits reversible diffusion restriction in the white matter, including the splenium. There have been a few previous reports of the change in fractional anisotropy (FA) of MERS cases. Herein, we report the longitudinal changes in axial and radial diffusivity (AD and RD), and FA in a 15-year-old boy patient with MERS. Our case demonstrated that a MERS lesion had a significant drop of AD in the early period and gradual recovery. On the contrary, RD did not show any significant change.

• Proceedings of the KAIS Fall Conference
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• 2010.05b
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• pp.1227-1229
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• 2010

This paper explains what DTI (Diffusion Tensor Imaging) is and what it does. We will talk about the DTI functions and what type of image it can show, and what areas are using DTI. The tractography and other applications that DTI is being used. In this paper, we explain that DTI is not only useful in medicine but also in botany. We propose to use DTI to study structure and functions of plants.

• Journal of Korean Port Research
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• v.12 no.2
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• pp.291-302
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• 1998

A digital image processing technique which is able to be used for getting the velocity vector distribution of a surface of the spilt oil in the ocean without contacting the flow itself. This technique is based upon the PIV(Particle Imaging Velocimetry) technique and its system mainly consists of a high sensitive camera, a CCD camera, an image grabber, and a host computer in which an image processing algorithm is adopted for velocity vector acquisition. For the acquisition of the advective velocity vector of floating matters on the ocean, a new multi-frame tracking algorithm is proposed, and for the acquisition of the diffusion velocity vector distribution of the spilt oil onto the water surface, a high sensitive gray-level cross-correlation algorithm is proposed.

• Proceedings of the Korea Information Processing Society Conference
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• 2013.05a
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• pp.747-750
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• 2013

알츠하이머병은 치매의 주요 원인 중 하나로 기억, 판단, 언어 등의 지적 기능의 감퇴뿐만 아니라 인격, 행동양상 장애 등을 동반하며 결국은 환자를 죽음에 이르게 하는 위험한 병이다. 본 연구는 뇌 백질의 비등방성을 잘 보여줄 수 있는 확산 텐서 영상 (diffusion tensor imaging; DTI) 데이터로 부터 신경섬유 경로를 생성하고, 알츠하이머병 환자와 정상인의 신경섬유 경로의 특징을 비교 분석 하였다. FSL 프로그램을 사용하여 생성한 신경섬유 경로에서 알츠하이머 환자와 정상인 집단간의 신경섬유 경로는 부피와 밝기에 커다란 차이를 보인다. 특히, 신경섬유 경로의 부피에서 현저한 차이가 있다는 점은 알츠하이머의 조기 진단에 유용하게 사용될 수 있다.

• Journal of the Korean Society of Radiology
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• v.83 no.6
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• pp.1354-1359
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• 2022

Glufosinate ammonium-containing herbicides are non-selective herbicides, used worldwide. With the increasing use of glufosinate ammonium-containing herbicides, cases of acute intoxication in suicide attempts have also increased. Herein, we report a case of a patient presenting cytotoxic edema in the posterior limbs of the bilateral internal capsules, bilateral middle cerebellar peduncles, and splenium of the corpus callosum on the brain diffusion-weighted MRI after glufosinate ammonium intoxication.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.14
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• pp.6135-6140
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• 2015

Background: The aim of this meta-analysis was to assess the efficacy of the apparent diffusion coefficient (ADC) value of diffusion-weighted MRI (DWI) for differentiating biliary tract cancer (BTC) from benign biliary tract diseases in Asians. Materials and Methods: We systematically searched Embase and PubMed prior to December 2014. Eight studies conducted in Asians met our predetermined inclusion criteria. Results: Our meta-analysis results showed that ADC values in BTC tissues were significantly lower than in benign biliary tract tissues (SMD = -1.54, 95%CI: -1.75~-1.33, P<0.001). Subgroup analysis based on the MRI machine type showed that the ADC values were consistent, accurate and reliable in the diagnosis of BTC when comparing cancer tissue vs. benign tissue under the Siemens 1.5 T/3.0 T, Philips 1.5 T/3.0 T, GE 1.5 T, and Toshiba 1.5 T types, respectively (all P<0.05). Further, ADC values were still consistent and accurate in the differential diagnosis of BTC under the b value of 800 and $1000s/mm^2$ (all P<0.05). Conclusions: Our findings supported potential clinical applications of DWI ADC values in differentiating BTC from benign biliary tract diseases in Asians.

• Journal of Korean Neurosurgical Society
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• v.46 no.6
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• pp.588-591
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• 2009

Radiologic findings of Bing-Neel syndrome, which is an extremely uncommon complication resulting from malignant lymphocyte infiltration into the central nervous system (CNS) in patients with Waldenstr$\ddot{o}$m's macroglobulinemia (WM), have been infrequently reported due to extreme rarity of the case. A 75-year-old man with WM presented at a neurology clinic with progressive gait and memory disturbances, and dysarthria of 2 months duration. Cerebrospinal fluid and serum protein electrophoresis and immunofixation electrophoresis showed IgM kappa-type monoclonal gammopathy. Brain magnetic resonance imaging revealed multifocal, hyperintense lesions on T2 weighted-images. Brain diffusion-weighted imaging (DWI) demonstrated hyperintensities in cerebral and cerebellar lesions that appeared isointense on apparent diffusion coefficient maps, which were compatible with vasogenic edema. Although histologic analysis is a confirmative study to prove direct cell infiltration into the brain, brain MRI with DWI may be a good supportive study to diagnose Bing-Neel syndrome.

• Investigative Magnetic Resonance Imaging
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• v.16 no.2
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• pp.184-188
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• 2012

Anoperineal tuberculosis is a rare extrapulmonary form of the disease and may present as abscess. We report a case of anoperineal tuberculous abscess, which showed low signal intensity on T1-weighted images, high signal intensity on T2-weighted images and diffusion restriction on diffusion weighted images.

• Investigative Magnetic Resonance Imaging
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• v.17 no.4
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• pp.312-315
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• 2013

When cerebral cortical hyperintensities on diffusion-weighted image are seen in patients with suspected acute stroke accompanying seizure, it is necessary to differentiate whether they are caused by infarction or seizure-related change. We report a case of seizure-related cortical hypertensities in a patient with suspected acute infarction. With perfusion MR imaging, we could differentiate from acute infarction.

• Investigative Magnetic Resonance Imaging
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• v.6 no.1
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• pp.21-27
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• 2002

Purpose : To evaluate diffusion-weighted imaging findings of intracerebral hematoma according to the time sequence. Materials and methods : Seventeen patients with intracerebral hematoma were studied. Diffusion weighted images using 1.5 tesla MRI machine were obtained with b-value of $1000{\;}sec/\textrm{mm}^2$. The patients were grouped as hyperacute stage(within 12 hours, 5 patients), acute stage(within 3 days, 4 patients), subacute stage(within 3 weeks, 4 patients), and chronic stage(after 3 weeks,4 patients). The signal intensities were analysed as bright, high, iso, low and dark at the central and peripheral portions of the hematoma in each stage, and compared with those of T2 and T1 weighted images. Results : The signal intensities of the central and peripheral portion of the intracerebral hematoma on diffusion-weighted images were high and dark in hyperacute stage, dark and high-bright in acute stage, and high-bright and dark in subacute and chronic stages. The patterns of signal change of hematoma on diffusion-weighted image according to the time sequence were similar to those on T2-weighted image, but changed early and prominently. Conclusion : The intracerebral hematoma on diffusion-weighted image showed unique central and peripheral signal intensity according to the time sequence. Central portions show high to bright signals in hyperacute, subacute and chronic stage, and dark signal in acute stage, and peripheral portions show dark signals in hyperacute, subacute and chronic stage, and high to bright signal in acute stage.