• Title/Summary/Keyword: White Matter

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BLUE STRAGGLERS, CATACLYSMIC VARIABLES, X-RAY BINARIES, AND MILLISECOND PULSARS IN GLOBULAR CLUSTERS

  • Lee, Hyung-Mok
    • Journal of The Korean Astronomical Society
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    • v.25 no.1
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    • pp.47-64
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    • 1992
  • Cores of globular clusters are an ideal place for close encounters between stars. The outcome of tidal capture can be stellar mergers, close binaries between normal stars (W UMa type), cataclysmic variables composed of white dwarf and normal star pairs, or low-mass X-ray binaries consisting of a neutron star and a normal star pairs. Stellar mergers can be the origin of blue stragglers in dense globular clusters although they are hard to observe. Low mass X-ray binaries would eventually become binary pulsars with short pulse periods after the neutron stars accrete sufficient amount of matter from the companion. However, large number of recently discovered, isolated millisecond pulsars (as opposed to binary pulsars) in globular clusters may imply that they do not have to gain angular speeds during the X-ray binary phase. We propose that these isolated millisecond pulsars may have formed through the disruptive encounters, which lead to the formation of accretion disk without Roche lobe filling companion, between a neutron star and a main-sequence star. Based on recently developed multicomponent models for the dynamical evolution of globular clusters, we compute the expected numbers of various systems formed by tidal capture as a function of time.

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A case of Reversible Posterior Leukoencephalopathy Syndrome in Lupus Nephritis Treated with Cyclosporine (루프스 신염 치료로 Cyclosporine 투여 후 발생한 가역성후백질뇌병증 증후군)

  • Na, Sang-Jun;Lee, Kee-Ook
    • Annals of Clinical Neurophysiology
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    • v.11 no.1
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    • pp.24-27
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    • 2009
  • Reversible posterior leukoencephalopathy syndrome (RPLS) is an acute encephalopathy, usually characterized by seizures, visual disorder, mental change and reversible posterior white and gray matter lesions on brain magnetic resonance imaging (MRI). Conditions commonly associated with RPLS include acute renal failure, eclampsia, hypertension, immunosuppresion state, and use of intravenous immunoglobulin or chemotherapy, and additional contributing factors. We report the case of RPLS associated with cyclosporine use in lupus nephritis. In this case, it was not clearly elucidated which was main cause of RPLS. We could think RPLS developed maybe due to combined effect of cyclosporine and lupus nephritis.

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Treatment of Acute Transverse Myelitis : a case report (하지마목으로 진단된 환자 치험 1례(例))

  • Kang, Hyung-Won;Lyu, Yeong-Su;Kim, Tae-Heon;Lee, Su-Jeong
    • Journal of Oriental Neuropsychiatry
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    • v.16 no.2
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    • pp.213-221
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    • 2005
  • Acute Transverse Myelitis is a syndrome, not a disease, in which acute inflammation affects gray and white matter in one or more adjacent thoracic segments. Almost all patients will develope ascending weakness and numbness of feet and leg, difficulty voiding, urinary retention, and loss of bowel control. We concluded this case to MAMOK( 마목) due to Qi ascent, Qi deficiency, Qi stoppage(상기, 기허, 기체). So we used herbal medication, acupuncture, and homeopuncture according to oriental medical theory. Weakness and numbness of feet and leg, difficulty voiding, urinary retention, and loss of bowel control are reduced. Herbal medication, acupuncture, and homeopuncture helped the care of this syndrome and further study will be investigated in oriental medicine for this syndrome.

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Bilateral Pallidotomy for Dystonia with Glutaric Aciduria Type 1

  • Hwang, Hyung-Sik;Salles, Antonio De
    • Journal of Korean Neurosurgical Society
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    • v.38 no.5
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    • pp.380-383
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    • 2005
  • Glutaric aciduria type 1 is an inborn error of lysine, hydroxylysine, and tryptophan metabolism caused by deficiency of glutaryl-coenzyme A dehydrogenase. The disease often appears in infancy with encephalopathy episode that results in acute basal ganglia and white matter degeneration. The majority of patients develop a dystonic-dyskinetic syndrome. This reports 6year-old boy who had been done previous gastrostomy due to swallowing difficulty underwent bilateral pallidotomy with intraoperative electromyography[EMG] monitoring for disabling dystonia. Intraoperative EMG was used to assess stimulation thresholds required for capsular responses and muscle tone. Surface EMG electrodes were placed on the face and cricopharyngeal muscles. Exact target were directly modified according to MRI-visualized anatomy. EMG response was consistently seen prior to visual observation of muscle activity. The surgery improved dystonic symptoms without swallowing difficulty.

Atypical Metronidazole-Induced Encephalopathy in Anaerobic Brain Abscess

  • Jang, Han Jin;Sim, Sook Young;Lee, Jong Yun;Bang, Ji Hwan
    • Journal of Korean Neurosurgical Society
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    • v.52 no.3
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    • pp.273-276
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    • 2012
  • Metronidazole-induced encephalopathy is a very rare complication of the long standing use of metronidazole. The encephalopathy is bilateral and symmetric in nature. We report on the magnetic resonance imaging (MRI) and clinical course of metronidazole-induced encephalopathy in a 60-year-old female with a persistent anaerobic brain abscess after draining of the abscess. After 3 months of metronidazole administration, the patient complained of dysarthria, tingling sense of all extremities, and left hemiparesis. MRI revealed symmetric hyperintensity lesions in medulla, pons, dentate nuclei of cerebellum, and splenium of corpus callosum, all of which represent typical findings of metronidazole-induced encephalopathy. In addition, asymmetric lesions in midbrain, thalamus, putamen and cerebral subcortical white matter were noted. The patient recovered after discontinuation of metronidazole and the remaining abscess was successfully treated with meropenem and levofloxacine.

Progressively Enlarged Intracerebral Ependymal Cyst Presenting with Movement Disorder

  • Lee, Seong-Jun;Hong, Chang-Ki;Ahn, Jung-Yong;Lee, Kyu-Sung
    • Journal of Korean Neurosurgical Society
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    • v.41 no.4
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    • pp.252-254
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    • 2007
  • Ependymal cysts are neuroepithelial cysts, typically found in the central white matter of the temporoparietal and frontal lobes. Clinical symptoms usually result from neurological deficits referable to these regions, from seizures, and chronic headaches associated with increased intracranial pressure. We describe here a case of ependymal cyst on the right fronto-parietal lobe, presenting with tremor and weakness. The cyst was resected surgically and presurgical neurological abnormalities were improved. An exploratory surgery with establishment of an adequate route of drainage and histological examination of the cyst wall are mandatory in the management of patients with a progressive and symptomatic intraparenchymal cyst.

Abnormal Region Extraction of Brain MR Images Using Mean of White-grey Matter Thickness (회백질 두께 평균치를 이용한 뇌 MR영상의 비정상 영역 추출)

  • 조경은;채정숙;조형제
    • Proceedings of the Korean Information Science Society Conference
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    • 2001.10b
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    • pp.466-468
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    • 2001
  • 의료 영상 처리 기술은 질병의 진단 및 치료를 위한 계획이나 방법을 결정하는데 있어 매우 중요한 역할을 하고 있으며 의료 영상 시스템과 같은 활용 분야에서는 질병이 있는 환자의 자동 진단을 위한 연구도 활발하게 이루어지고 있다. 여기서는 뇌 MR영상에서의 질병을 자동 진단할 수 있는 방법에 관한 연구를 한다. 뇌 MR영상에서의 질병 진단을 위한 단계로서 필수적으로 이루어져야 하는 단계가 비정상 영역의 추출 단계이다. 이 논문에서는 뇌의 질병 진단에 사용할 수 있는 자료를 제공하기 위한 전처리 단계로서 질병이 있는 환자의 뇌 영상에서 비정상적인 영역 추출 방법을 제안한다. 일반적으로 비정상적인 영역의 명암간 분포는 회백질 영역의 분포와 유사하나 두께 차이로서 구분이 가능하다. 여기서는 이 정보를 활용하여 정상인의 뇌영상에 대해서 회백질의 평균 두께 분포를 구하여 테스트로 입력되어지는 영상에서 회백질의 평균 두께 이상의 영역만을 남김으로서 질병이 있는 환자의 뇌 영상에서 비정상적인 영역을 추출할 수 있음을 보인다. 또한 추출되어진 비정상 영역에 대해서 진단에 필요한 인자를 자동으로 측정하였고 뇌경색, 뇌종양 환자를 포함한 63명의 뇌 MR 영상 시리즈에 대해서 실험하여 비교적 정확한 추출결과를 유도할 수 있었음을 확인하였다.

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EVALUATION OF AUDITORY EVOKED POTENTIALS IN WHITE NEW ZEALAND RABBITS WITH SIMULATED SUBDURAL HEMATOMA AND INCREASED INTRACRANIAL PRESSURE (경막혈종 및 뇌내압 증가에 따른 청각 유발전위의 분석)

  • Im, Jae-Joong
    • Proceedings of the KOSOMBE Conference
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    • v.1992 no.05
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    • pp.171-174
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    • 1992
  • Development of a noninvasive intensive care system calls for the use of evoked potentials (EPs), as a means of diagnosing traumatic head-injured patients. The experiment entails surgically plating two subarachnoid bolts and a subdural balloon through the skull to simulate a subdural hematoma. Using various levels of intracranial pressure (ICP) and/or different sizes of balloons, auditory evoked potentials (AEPs) were recorded from a rabbit. Six positive peat latencies ($P_1-P_6$) and five negative peak latencies ($N_1-N_5$) were extracted from an averaged AEP waveform. Multiple regression analyses were performed for determining a relationship between the ICP and AEP peak latencies. The results indicate that a major correlation of changes on AEP peak latencies is due to mechanical forcer of a mass (inflated balloon simulating a hematoma) in the distortion of the brain matter rather than increased ICP.

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