M-mode TCD를 이용한 한 중대뇌동맥의 양측 측두창을 통한 동시 탐지

양현덕,손일홍,석승한 대한신경과학회 2005 대한신경과학회지 Vol.23 No.2

Background: Transcranial Doppler ultrasonography (TCD) is limited by insufficient ultrasound penetration through the temporal bone. Recent studies have revealed poor temporal bone windows in 5~30% of patients. In about 38% of the patients with poor temporal bone windows, a temporal window was unilaterally absent. The aim of the present study was to compare the mean flow velocities (MFV) of the middle cerebral arteries (MCA) obtained through the ipsilateral temporal bone window with those obtained through the contralateral one using M-mode TCD. Methods: Eighteen patients (mean age, 28 y; age range, 21~40 y) who had adequate bilateral temporal bone windows were enrolled and 36 MCAs were investigated. The investigators tried to detect the MCA through the ipsilateral and contralateral temporal windows with two 2-MHz probes simultaneously (ipsilateral insonation and contralateral one, respectively). Results: The MCA MFV measured by ipsilateral insonation was 72.58±9.78 cm/sec and that demonstrated by contralateral insonation was 70.94±9.79 cm/sec. Even though the differences between MFVs by either side insonation was 2.25~3.94% (0~13.11%) and had significant difference statistically, those were within side-to-side limit of 30% generally considered as abnormal. The mean bitemporal diameter (BTD) was 130.72±3.75 cm (126~142 cm). We obtained similar waveforms in the reverse direction to those of ipsilateral insonation at 95.33±5.19 mm of depths (72.97±4.23% of BTD) during contralateral insonation. Conclusions: The demonstration of the MCA through the contralateral insonation provides an opportunity to obtain significant mean flow velocities in patients with absent or insufficient temporal bone window unilaterally.

Misfolded Proteins in Neurodegenerative Dementias: Molecular Mechanisms

양현덕,호동환,이명재,김상윤 대한치매학회 2012 Dementia and Neurocognitive Disorders Vol.11 No.2

During recent years, there has been remarkable progress with respect to the identification of molecular mechanisms and underlying pathology of neurodegenerative dementias. The latest evidence indicates that a common cause and pathological mechanism of diverse neurodegenerative dementias can be found in the increased production, misfolding, aggregation, and accumulation of specific proteins such as β-amyloid, tau protein, α-synuclein, prion protein, polyglutamine, transactive response DNA-binding protein (TARDBP or TDP-43), or fused in sarcoma (FUS). The conformational variants of these proteins range from small oligomers to the characteristic pathologic inclusions. However, it is noteworthy that a certain pathology can be a hallmark of a certain dementia, but there is a substantial overlap between different pathologies and different types of dementias. In this review, molecular mechanisms and pathologies of different neurodegenerative dementias will be summarized from the perspective of proteins rather than from the viewpoint of individual dementias. We will also review recent evidence surrounding these protein misfolding disorders, the role of toxic oligomers, cell-to-cell transmission, and the links between the misfolded proteins, along with the general therapeutic strategies for the protein misfolding disorders.

뇌졸중 환자에서 경피적내시경적위루술 : 합병증과 결과

양현덕,강성원,이성익,손일홍,김용성 圓光大學校 醫科學硏究所 2006 圓光醫科學 Vol.21 No.1

급성 척수 경색의 확산 강조 자기공명 영상 - 증례보고 -

양현덕,오성균,심대무 대한척추외과학회 2013 대한척추외과학회지 Vol.20 No.2

Study Design: A case report. Objective: We present a rare case of acute spinal cord infarction and usefulness of diffusion weighted MR imaging. Summary of Literature Review: T1-weighted and T2-weighted images are often normal in a patient with acute spinal cord infarction. Material and Methods: An 82-year-old presented with acute onset of paraplegia and urinary retention. His symptoms developed 6 days ago without any trauma. He had a history of vertebroplasty due to compression fracture of 12th thoracic vertebral body 6 years ago. There was no evidence of spinal cord compression on routine T1-and T2-weighted MRI. Results: In diffusion-weighted MRI, a high intensity signal intensity lesion in the spinal cord and conus medullaris was observed. Conclusion: We report an example for the usefulness of diffusion-weighted image for early and accurate diagnosis of acute spinal cord infarction. 연구 계획: 증례 보고목적: 급성 척수 경색의 임상특징과 확산강조 자기공명영상 소견에 대해 보고하고자 한다. 선행문헌의 요약: 급성 척수 경색의 경우 실제 임상에서 매우 드물고 초기에 자기공명검사상 정상소견을 보이는 경우도 있어 조기 진단이 어렵다. 대상 및 방법: 급성으로 발생한 양측 하지 마비 및 요폐 증상을 주소로 내원한 82세 남자환자로 과거력상 6년 전 흉추 12번 압박골절로 척추 성형술을시행한 과거력이 있으며 응급으로 시행한 자기공명검사 소견상 척수를 압박하는 소견은 관찰되고 있지 않았다. 결과: 확산 강조 자기공명 영상 소견상 고신호 영상 소견이 흉요추부 및 원추부 척수내부에 관찰되었다. 결론: 급성 척수 경색의 경우 초기에 확산 강조 자기공명 영상에 고신호 강도의 척수 신호를 보이므로 조기 진단 및 감별진단에 도움이 된다. 색인 단어: 척수, 경색, 확산 강조 자기공명영상약칭 제목: 척수경색의 확산 강조 자기공명 영상

Subtypes of Amnestic Mild Cognitive Impairment Based on Memory Impairment Pattern and Its Potential Clinical Significance

양현덕,양영순,Benalfew T. Legesse,김상윤 대한치매학회 2012 Dementia and Neurocognitive Disorders Vol.11 No.2

Background: Episodic memory impairment can be subdivided into two subtypes, encoding failure vs. retrieval deficit. We defined two subtypes of amnestic mild cognitive impairment (aMCI) according to recognition performance on the memory test: aMCI with encoding failure or aMCI-E and aMCI with retrieval deficit or aMCI-R. We hypothesized that compared to aMCI-R, subjects with aMCI-E are more likely to convert to Alzheimer’s disease, as encoding failure suggests that medial temporal lobes are affected early in the disease process. We also investigated whether aMCI-E can be a predictor for progression to AD. Methods: Using the Alzheimer’s Disease Neuroimaging Initiative (ADNI) database, a total of 397 aMCI subjects were included. APOE genotype, cerebrospinal fluid (CSF) fluid biomarkers, and a set of neuropsychological measures were also collected. Unadjusted and adjusted odds ratios were calculated to predict the conversion to AD dementia. The Spearman’s rs test was used to measure the degree of correlation between aMCI subtypes and the prognostic factors for progression to AD. Results: Among the 397 subjects, 209 (52.6%) subjects were classified into aMCI-E and 188 (47.4%) into aMCI-R. One hundred two (48.8%) subjects with aMCI-E and 57 (30.3%) of those with aMCI-R progressed to AD (unadjusted odds ratio=2.19 with 95% confidence interval [CI] 1.45-3.31) over 3 years. However, when adjusted odds ratio by a logistic regression was calculated, probability value of aMCI-E disappeared with the odds of conversion by of 1.47 (95% CI 0.89-2.43). There were statistically significant correlations between aMCI-E subtype and MMSE, CDR Memory, RAVLT delayed recall, CSF biomarkers, and genotypes. Conclusions: This analysis did not show that aMCI-E is an independent prognostic factor to predict the progression to AD. However, this subtype significantly correlates with other prognostic factors for progression. This may suggest that aMCI-E might be a later stage of aMCI and aMCI-R an earlier stage which might be a better target than aMCI-E for therapeutic intervention. Further studies are needed to validate this conjecture.

급성 시상부위 뇌경색 환자에서 보인 가역적 뇌교병변 (뇌자기공명영상촬영): 고혈압에 의한 가역적 뇌증인가?

양현덕,강성원,정진성,이성익,송일홍,김형진 대한신경과학회 2006 대한신경과학회지 Vol.24 No.6

Posterior reversible encephalopathy syndrome associated with hypertension rarely presents with predominant involvement of the brainstem and is relative sparing of the supratentorial regions. A relative paucity of brainstem signs and symptoms, despite extensive neuroimaging abnormalities therein, support the diagnosis. Although elevation of blood pressure is common in acute cerebral infarction, concomitant brainstem edema has not been reported. We describe here the clinical and neuroimaging features of an unusual brainstem hyperintensity associated with acute ischemic stroke. The neuroimaging abnormalities improved after stabilization of blood pressure, distinguishing this syndrome from brainstem infarction.

항공우주산업의 비파괴검사 기술동향

양현덕,이경철,이강이,진영권 한국항공우주연구원 2005 항공우주산업기술동향 Vol.3 No.2

치원성 상악동염에 동반된 위시상 및 직정맥동혈전증

양현덕,손일홍,석승한,조광호 圓光大學校 醫科學硏究所 2004 圓光醫科學 Vol.19 No.2

소뇌 출혈을 동반한 침입성 부비동 아스페르길루스증 1예

양현덕,박성욱,손일홍,이지용,석승한,조광호,이성수 圓光大學校 醫科學硏究所 2003 圓光醫科學 Vol.18 No.2

통행 OD 및 교통인프라 네트워크 분석을 통한 도심항공교통 버티포트 허브 선정 방안 연구

양현덕,홍정열 한국ITS학회 2023 한국ITS학회 학술대회 Vol.2023 No.11