Biomedical subjects

Hee-Joon Bae

Publications and source records attributed to Hee-Joon Bae.

8 recordsLinked to original sources

PubMed2005

Correlation of coronary and cerebral atherosclerosis: difference between extracranial and intracranial arteries.

BACKGROUND: A difference with regard to the correlation with coronary atherosclerosis (CAS) between extracranial carotid atherosclerosis (ECAS) and intracranial cerebral atherosclerosis (ICAS) has been assumed but not proven clearly by direct comparison within the same population. METHODS: A consecutive series of 246 patients undergoing coronary artery bypass graft surgery were reviewed. The severity of CAS was estimated as a CAS score based on coronary angiography. The presence of ECAS and ICAS was screened by transcranial Doppler and carotid duplex sonography, and confirmed by magnetic resonance angiography. RESULTS: The CAS scores in patients with ECAS were observed to be higher than those in patients without ECAS (10.62+/- 4.80 vs. 9.45+/- 4.25; p=0.054 on the Mann-Whitney U test). The difference in CAS scores was smaller between patients with and without ICAS (10.41+/- 4.44 vs. 9.66+/- 4.49; p=0.201). Similar patterns were observed on comparing the correlation of ECAS and ICAS with a quartile of the CAS score. An advanced CAS, which was generated by collapsing the quartiles of the CAS score into 75th percentile or less and more than the 75th percentile, was significantly associated with ECAS, but not with ICAS. These associations remained unchanged after adjustments had been made for age, sex, hypertension, diabetes mellitus, hyperlipidemia, smoking and a history of stroke or transient ischemic attack. CONCLUSIONS: This study suggests that the correlation of CAS with ECAS is stronger than that of CAS with ICAS, and this difference is independent of the classic risk factors for atherosclerosis.

Aged↗

PubMed2005

In-hospital medical complications and long-term mortality after ischemic stroke.

BACKGROUND AND PURPOSE: Inhospital medical complications account for a considerable portion of deaths during the early stage of stroke. However, relatively few studies have examined their long-term effects on mortality in stroke patients. METHODS: We prospectively and consecutively collected data on 579 patients with acute ischemic stroke from November 1998 to February 2001. Mortality was confirmed using national death certificate data from 1999 to 2003. RESULTS: During admission, one or more medical complications requiring intervention developed in 160 of these 579 patients (27.6%). For these 160 subjects, the 30-day, 90-day, 1-year, 2-year, 3-year, and 4-year mortalities were 16.3, 29.4, 46.9, 55.6, 61.3, and 70.7%, whereas the mortality figures for those without such complications (n=419) were 1.4, 3.8, 8.8, 15.0, 19.1, and 22.4 (P<0.001 with log-rank test). To eliminate the short-term effects of these complications and thus reveal their long-term effects, we investigated differences in mortality versus the presence of inhospital complications at more than 30 days, 90 days, 1 year, 2 years, and 3 years after stroke, respectively. Cox's proportional hazard regression analysis was applied at these times after stroke and showed that all hazard ratios of medical complications in terms of mortality were statistically larger than one, regardless of adjusting for effects of potential predictors on mortality. CONCLUSIONS: Our study shows that stroke patient mortality is influenced by inhospital medical complications significantly up to the chronic stage. This finding suggests that the appropriate prevention and management of inhospital complications could improve short-term and long-term prognoses after stroke.

Aged↗

PubMed2005

Cilostazol prevents the progression of the symptomatic intracranial arterial stenosis: the multicenter double-blind placebo-controlled trial of cilostazol in symptomatic intracranial arterial stenosis.

BACKGROUND AND PURPOSE: Cilostazol, a phosphodiesterase inhibitor, has been reported to reduce restenosis rate after coronary angioplasty and stenting. This study was performed to investigate the effect of cilostazol on the progression of intracranial arterial stenosis (IAS). METHODS: We randomized 135 patients with acute symptomatic stenosis in the M1 segment of middle cerebral artery or the basilar artery to either cilostazol 200 mg per day or placebo for 6 months. Aspirin 100 mg per day was also given to all patients. Patients with potential embolic sources in the heart or extracranial arteries were excluded. IAS was assessed by magnetic resonance angiogram (MRA) and transcranial Doppler (TCD) at the time of recruitment and 6 months later. The primary outcome was the progression of symptomatic IAS on MRA and secondary outcomes were clinical events and progression on TCD. RESULTS: Thirty-eight patients were prematurely terminated. Dropout rates and reasons for dropouts were similar between the cilostazol and placebo groups. There was no stroke recurrence in either cilostazol or placebo group, but there was 1 death and 2 coronary events in each group. In cilostazol group, 3 (6.7%) of 45 symptomatic IAS progressed and 11 (24.4%) regressed. In placebo group, 15 (28.8%) of symptomatic IAS progressed and 8 (15.4%) regressed. Progression of symptomatic IAS in cilostazol group was significantly lower than that in placebo group (P=0.008) CONCLUSIONS: Our study suggests that symptomatic IAS is a dynamic lesion and cilostazol may prevent its progression.

Aged↗

PubMed2005

Treatment of vascular dementia: evidence from epidemiologic studies.

This article discusses the most relevant recent evidence on the prevention and treatment of vascular dementia from epidemiologic studies. Vascular dementia is the most common form of dementia after Alzheimer's disease and remains the only one that is preventable, although most of our knowledge about primary and secondary prevention of vascular dementia comes from direct extrapolation from works in stroke. Furthermore, at present there are no approved therapeutic agents for the treatment of vascular dementia. Recently, however, a number of reasonable studies on vascular dementia have been available. It is clear that rigorous control of vascular risk factors is important in primary and secondary prevention of vascular dementia, and perhaps in ameliorating its mild form. A rational therapeutic approach to the treatment of vascular dementia should be based on an understanding of its broad clinical spectrum and the diverse causes that may be responsive to currently available treatments.

Journal Article↗

PubMed2004

Clinical and radiologic differences between primary intracerebral hemorrhage with and without microbleeds on gradient-echo magnetic resonance images.

BACKGROUND: Microbleeds on gradient-echo magnetic resonance (MR) imaging reflect bleeding-prone microangiopathy. The microbleeds are frequently detected in patients with primary intracerebral hemorrhage (PICH). However, some patients do not have microbleeds. OBJECTIVE: To clarify the risk factors associated with microbleeds in PICH, thus providing insight into the pathogenesis of PICH. DESIGN: Prospective study. SETTING: Neurology department of a tertiary referral center. Patients A consecutive series of 107 patients with PICH. INTERVENTIONS: Gradient-echo MR imaging to determine distribution patterns and numbers of microbleeds. MAIN OUTCOME MEASURES: Clinical variables and the associated MR imaging abnormalities in patients with PICH with and without microbleeds. RESULTS: Patients with PICH who had microbleeds were significantly older (65.9 +/- 10.9 years) than those without microbleeds (53.9 +/- 13.0 years; P<.001), and previous stroke, medication with antithrombotics or anticoagulants, lacunes, and leukoaraiosis were more common in patients with microbleeds. However, potential triggering events tending to raise the blood pressure were more common in cases of PICH without microbleeds (18 [56.3%] vs 10 [15.4%]). In logistic regression analysis, age (odds ratio and 95% confidence interval: 1.07, 1.01-1.14), advanced leukoaraiosis (7.79, 1.05-57.74), number of lacunes (1.66, 1.21-2.28), and potential triggering events (0.18, 0.04-0.90) were independent risk factors associated with the presence of microbleeds in patients with PICH. CONCLUSIONS: Primary intracerebral hemorrhage without microbleeds was more common in younger patients with precipitating events, whereas PICH with microbleeds was more common in elderly patients with prominent ischemic change and frequent use of antithrombotics or anticoagulants. Our findings might help to determine the pathogenetic type for secondary prevention.

Adolescent↗

PubMed2003

Cerebral cavernous malformations with dynamic and progressive course: correlation study with vascular endothelial growth factor.

BACKGROUND: Cerebral cavernous malformations (CCMs) are reported to exhibit a wide range of dynamic patterns including growth, regression, and de novo formation, which generally show slow and steady courses. Although the pathogenesis of CCMs is not well known, vascular endothelial growth factor (VEGF) has been suggested as a possible mediating factor. OBJECTIVES: To report CCMs showing rapid progression over a short period and to investigate these biological characteristics. DESIGN: Experimental study. SETTING: Tertiary referral center, neurology department. Patient A 40-year-old man was admitted because of a left-sided numbness, vertigo, and ataxia, which were attributed to a pontine hemorrhage. He had experienced a left-sided weakness 6 months before admission, and thereafter had complained of intermittent headache. Serial brain magnetic resonance images showed multiple intracerebral microhemorrhages throughout the cerebral hemispheres. A biopsy of the lesion confirmed the diagnosis of CCM. MAIN OUTCOME MEASURES: We investigated the expression of VEGF by immunohistochemistry of the biopsy specimen. Dynamic patterns of CCMs, obtained with spin-echo magnetic resonance images with gradient-echo sequences, were compared with serial serum VEGF concentrations, determined by enzyme-linked immunosorbent assay. RESULTS: Immunohistochemistry of the specimen displayed increased VEGF expression. Serial magnetic resonance images during 7 months showed dynamic signal changes of the preexisting lesions and 15 de novo formations in many cortices. The VEGF level in serum increased during this dynamic period and became normal during the steady and resolving stages. CONCLUSIONS: Cerebral cavernous malformations can be progressively deteriorating. The endothelial proliferation induced by VEGF is likely to be an important aspect of the pathogenetic mechanisms of CCMs.

Adult↗

PubMed2002

Gradient echo magnetic resonance imaging in the prediction of hemorrhagic vs ischemic stroke: a need for the consideration of the extent of leukoariosis.

BACKGROUND: Multifocal signal loss lesion (MSLL) on gradient echo magnetic resonance imaging (GE-MRI) may reflect bleeding-prone microangiopathy. However, MSLLs are also known to be associated with leukoariosis; leukoariosis is commonly associated with occlusive-type vascular lesions. OBJECTIVE: To determine whether MSLL on GE-MRI is significantly associated with the type of stroke--intracerebral hemorrhagic (ICH) stroke more often than an ischemic stroke (infarction)--regardless of the extent of leukoariosis. PATIENTS AND METHODS: We studied 91 patients who had an acute stroke and were admitted to the Department of Neurology, Seoul National University Hospital, Seoul, South Korea, from March 1, 1997, to July 31, 1998. These patients underwent both conventional MRI and GE-MRI. The GE-MRI was used to count MSLLs. We also counted lacunae and classified leukoariosis (none or mild and advanced). Multiple logistic regression analysis was used to test for MSLL-leukoariosis interaction association with the type of stroke (ICH over infarction) and to evaluate the relative contribution of an MSLL--adjusted for age, sex, and lacunae--in discriminating the type of stroke. RESULTS: The association between MSLL and ICH statistically significantly differed by leukoariosis (P =.003 for MSLL-leukoariosis interaction term). The MSLL count on GE-MRI was significantly associated with the type of stroke (ICH over infarction; odds ratio, 2.46; 95% confidence interval, 1.38-4.39) when leukoariosis was classified as none or mild. When leukoariosis was classified as advanced, there was a decrease in the odds ratio of MSLL to 0.99 (95% confidence interval, 0.94-1.04). CONCLUSIONS: Our findings indicate that MSLL on GE-MRI is a predictor of ICH vs infarction in patients with no or mild leukoariosis, but not in patients with advanced leukoariosis. Therefore, in the evaluation of GE-MRI for a bleeding-prone microangiopathy, the extent of leukoariosis should be considered.

Adult↗

PubMed2002

Low concentration of serum total cholesterol is associated with multifocal signal loss lesions on gradient-echo magnetic resonance imaging: analysis of risk factors for multifocal signal loss lesions.

BACKGROUND AND PURPOSE: Multifocal signal loss lesions (MSLLs) on T2*-weighted gradient-echo (GE) MRI are believed to be microbleeds histopathologically. Previous epidemiological studies suggested that low serum cholesterol is associated with the increased risk of intracerebral hemorrhage. We investigated risk factors of MSLLs and the relationship between lipid profiles and MSLLs on GE-MRI. METHODS: We included consecutively 172 patients who underwent brain MRI. MSLLs on GE-MRI were counted by 2 neurologists separately and graded by consensus. The concentrations of lipid profiles were categorized as quartiles, and the MSLLs were graded as absent (total count, 0), mild (1 to 2), moderate (3 to 10), and severe (>10). RESULTS: The mean concentrations of total cholesterol and low-density lipoprotein cholesterol were significantly lower in patients with a severe degree of MSLLs than in those without MSLL (P<0.05). By multivariate analysis, MSLLs were significantly correlated with hypertension (odds ratio [OR], 3.42; 95% CI, 1.17 to 9.97), leukoaraiosis (OR, 4.62; 95% CI, 2.87 to 7.41), the lowest quartile of serum total cholesterol (<4.27 mmol/L; OR, 10.91; 95% CI, 3.98 to 25.57), and the highest quartile of high-density lipoprotein (>1.47 mmol/L; OR, 3.5; 95% CI, 1.45 to 8.29). CONCLUSIONS: Our results suggest that both the lipid profile levels and the severity of hypertension may be closely associated with MSLLs on GE-MRI.

Adult↗