BACKGROUND AND PURPOSE: The primary mechanism underlying paramedian pontine infarction (PPI) is atheroma obliterating the perforators. Here, we encountered a patient with PPI in the post-stenotic area of basilar artery (BA) without a plaque, shown by high-resolution magnetic resonance imaging (HR-MRI). We performed an experiment using a 3D-printed BA model and a particle image velocimetry (PIV) to explore the hemodynamic property of the post-stenotic area and the mechanism of PPI. METHODS: 3D-model of a BA stenosis was reconstructed with silicone compound using a 3D-printer based on the source image of HR-MRI. Working fluid seeded with fluorescence particles was used and the velocity of those particles was measured horizontally and vertically. Furthermore, microtubules were inserted into the posterior aspect of the model to measure the flow rates of perforators (pre-and post-stenotic areas). The flow rates were compared between the microtubules. RESULTS: A recirculating flow was observed from the post-stenotic area in both directions forming a spiral shape. The velocity of the flow in these regions of recirculation was about one-tenth that of the flow in other regions. The location of recirculating flow well corresponded with the area with low-signal intensity at the time-of-flight magnetic resonance angiography and the location of PPI. Finally, the flow rate through the microtubule inserted into the post-stenotic area was significantly decreased comparing to others (P<0.001). CONCLUSIONS: Perforator infarction may be caused by a hemodynamic mechanism altered by stenosis that induces a recirculation flow. 3D-printed modeling and PIV are helpful understanding the hemodynamics of intracranial stenosis.
Basilar Artery ; Constriction, Pathologic ; Fluorescence ; Hemodynamics* ; Humans ; Infarction* ; Magnetic Resonance Angiography ; Magnetic Resonance Imaging ; Microtubules ; Plaque, Atherosclerotic ; Rheology ; Silicon ; Silicones

BACKGROUND AND PURPOSE: The primary mechanism underlying paramedian pontine infarction (PPI) is atheroma obliterating the perforators. Here, we encountered a patient with PPI in the post-stenotic area of basilar artery (BA) without a plaque, shown by high-resolution magnetic resonance imaging (HR-MRI). We performed an experiment using a 3D-printed BA model and a particle image velocimetry (PIV) to explore the hemodynamic property of the post-stenotic area and the mechanism of PPI. METHODS: 3D-model of a BA stenosis was reconstructed with silicone compound using a 3D-printer based on the source image of HR-MRI. Working fluid seeded with fluorescence particles was used and the velocity of those particles was measured horizontally and vertically. Furthermore, microtubules were inserted into the posterior aspect of the model to measure the flow rates of perforators (pre-and post-stenotic areas). The flow rates were compared between the microtubules. RESULTS: A recirculating flow was observed from the post-stenotic area in both directions forming a spiral shape. The velocity of the flow in these regions of recirculation was about one-tenth that of the flow in other regions. The location of recirculating flow well corresponded with the area with low-signal intensity at the time-of-flight magnetic resonance angiography and the location of PPI. Finally, the flow rate through the microtubule inserted into the post-stenotic area was significantly decreased comparing to others (P<0.001). CONCLUSIONS: Perforator infarction may be caused by a hemodynamic mechanism altered by stenosis that induces a recirculation flow. 3D-printed modeling and PIV are helpful understanding the hemodynamics of intracranial stenosis.
Basilar Artery ; Constriction, Pathologic ; Fluorescence ; Hemodynamics* ; Humans ; Infarction* ; Magnetic Resonance Angiography ; Magnetic Resonance Imaging ; Microtubules ; Plaque, Atherosclerotic ; Rheology ; Silicon ; Silicones

Osteoporosis is a medical condition of global concern, with increasing incidence in both sexes. Bone mineral density (BMD), a highly heritable trait, has been proven a useful diagnostic factor in predicting fracture. Because medical information is lacking about male osteoporotic genetics, we conducted a genome-wide association study of BMD in Korean men. With 1,176 participants, we analyzed 4,414,664 single nucleotide polymorphisms (SNPs) after genomic imputation, and identified five SNPs and three loci correlated with bone density and strength. Multivariate linear regression models were applied to adjust for age and body mass index interference. Rs17124500 (p = 6.42 × 10⁻⁷), rs34594869 (p = 6.53 × 10⁻⁷) and rs17124504 (p = 6.53 × 10⁻⁷) in 14q31.3 and rs140155614 (p = 8.64 × 10⁻⁷) in 15q25.1 were significantly associated with lumbar spine BMD (LS-BMD), while rs111822233 (p = 6.35 × 10⁻⁷) was linked with the femur total BMD (FT-BMD). Additionally, we analyzed the relationship between BMD and five genes previously identified in Korean men. Rs61382873 (p = 0.0009) in LRP5, rs9567003 (p = 0.0033) in TNFSF11 and rs9935828 (p = 0.0248) in FOXL1 were observed for LS-BMD. Furthermore, rs33997547 (p = 0.0057) in ZBTB and rs1664496 (p = 0.0012) in MEF2C were found to influence FT-BMD and rs61769193 (p = 0.0114) in ZBTB to influence femur neck BMD. We identified five SNPs and three genomic regions, associated with BMD. The significance of our results lies in the discovery of new loci, while also affirming a previously significant locus, as potential osteoporotic factors in the Korean male population.
Asian Continental Ancestry Group ; Body Mass Index ; Bone Density* ; Femur ; Femur Neck ; Genetics ; Genome-Wide Association Study* ; Humans ; Incidence ; Linear Models ; Male ; Osteoporosis ; Polymorphism, Single Nucleotide ; Spine

The aim of the Part I of Stroke Statistics in Korea is to summarize nationally representative data of the epidemiology and risk factors of stroke in a single document. Every year, approximately 105,000 people experience a new or recurrent stroke and more than 26,000 die of stroke, which indicates that every 5 minutes stroke attacks someone and every 20 minutes stroke kills someone in Korea. Stroke accounts for roughly 1 of every 10 deaths. The estimated stroke prevalence is about 795,000 in people aged > or =30 years. The nationwide total cost for stroke care was 3,737 billion Korean won (US$3.3 billion) in 2005. Fortunately, the annual stroke mortality rate decreased substantially by 28.3% during the first decade of the 21th century (53.2/100,000 in 2010). Among OECD countries, Korea had the lowest in-hospital 30-day case-fatality rate for ischemic stroke and ranked third lowest for hemorrhagic stroke in 2009. The proportion of ischemic stroke has steadily increased and accounted for 76% of all strokes in 2009. According to hospital registry studies, the 90-day mortality rate was 3-7% for ischemic stroke and 17% for intracerebral hemorrhage. For risk factors, among Korean adults > or =30 years of age, one in 3-4 has hypertension, one in 10 diabetes, and one in 7 hypercholesterolemia. One in 3 Korean adults > or =19 years of age is obese. Over the last 10 years, the prevalence of hypertension slightly decreased, but the prevalence of diabetes, hypercholesterolemia, and obesity increased. Smoking prevalence in men has decreased, but is still as high as 48%. This report could be a valuable resource for establishing health care policy and guiding future research directions.
Adult ; Aged ; Cerebral Hemorrhage ; Delivery of Health Care ; Humans ; Hypercholesterolemia ; Hypertension ; Korea ; Male ; Obesity ; Prevalence ; Risk Factors ; Smoke ; Smoking ; Stroke

The aim of the current Part II of Stroke Statistics in Korea is to summarize nationally representative data on public awareness, pre-hospital delay, thrombolysis, and quality of acute stroke care in a single document. The public's knowledge of stroke definition, risk factors, warning signs, and act on stroke generally remains low. According to studies using open-ended questions, the correct definition of stroke was recognized in less than 50%, hypertension as a stroke risk factor in less than 50%, and other well-defined risk factors in less than 20%. Among stroke warning signs, sudden paresis or numbness was best appreciated, with recognition rates ranging in 36.9-73.7%, but other warning signs including speech disturbance were underappreciated. In addition, less than one third of subjects in a representative population survey were aware of thrombolysis and had knowledge of the appropriate act on stroke, calling emergency medical services (EMS). Despite EMS being an essential element in the stroke chain of survival and outcome improvement, EMS protocols for field stroke diagnosis and prehospital notification for potential stroke patients are not well established. According to the Assessment for Quality of Acute Stroke Care, the median onset-to-door time for patients arriving at the emergency room was 4 hours (mean, 17.3 hours) in 2010, which was not reduced compared to 2005. In contrast, the median door-to-needle time for intravenous tissue plasminogen activator (IV-TPA) treatment was 55.5 minutes (mean, 79.5 minutes) in 2010, shorter than the median time of 60.0 minutes (mean, 102.8 minutes) in 2008. Of patients with acute ischemic stroke, 7.9% were treated with IV-TPA in 2010, an increase from the 4.6% in 2005. Particularly, IV-TPA use for eligible patients substantially increased, from 21.7% in 2005 to 74.0% in 2010. The proportion of hospitals equipped with a stroke unit has increased from 1.1% in 2005 to 19.4% in 2010. Performance, as measured by quality indicators, has steadily improved since 2005, and the performance rates for most indicators were greater than 90% in 2010 except for early rehabilitation consideration (89.4%) and IV-TPA use for eligible patients (74.0%). In summary, the current report indicates a substantial improvement in in-hospital acute stroke care, but also emphasizes the need for enhancing public awareness and integrating the prehospital EMS system into acute stroke management. This report would be a valuable resource for understanding the current status and implementing initiatives to further improve public awareness of stroke and acute stroke care in Korea.
Emergencies ; Emergency Medical Services ; Humans ; Hypertension ; Hypesthesia ; Korea ; Paresis ; Quality Indicators, Health Care ; Risk Factors ; Stroke ; Tissue Plasminogen Activator

BACKGROUND AND PURPOSE: Intracranial atherosclerotic stenosis (ICAS) is considered as a major cause of stroke. The carotid intima-media thickness (CIMT), which accurately reflects the burden of generalized atherosclerosis, is also associated with stroke. The aim of this study was to determine the association between the CIMT and ICAS responses to medical treatment. METHODS: This study constituted part of the "Trial of cilostazol in symptomatic intracranial arterial stenosis"-2 that evaluated the ICAS response after randomized antiplatelet treatment. Magnetic resonance angiography and CIMT measurement were performed at baseline and after 7 months of treatment. CIMT was measured using semiautomated software, and was presented as maximum (CIMT-max) and average (CIMT-ave) values. The change in CIMT was compared relative to the ICAS response (i.e., progression, no-change, and regression). Ordinal logistic regression and analysis of covariance (ANCOVA) were used to analyze the association between the responses. RESULTS: Among the 101 enrolled patients, 85 underwent follow-up CIMT measurement. CIMT increased most in the ICAS progression group (CIMT-max: 0.09+/-0.23, CIMT-ave: 0.04+/-0.12), and to a lesser degree in the no-change group (CIMT-max: 0.02+/-0.16, CIMT-ave: 0.02+/-0.11), but decreased in patients with ICAS regression (CIMT-max: -0.04+/-0.11, CIMT-ave: -0.03+/-0.07; CIMT-max: p=0.010, CIMT-ave: p=0.015). Ordinal logistic regression analysis demonstrated that the change in CIMT-max was independently associated with the ICAS response (p=0.032). However, the ANCOVA revealed that the reverse was not true, in that the ICAS response was not independently associated with the change in CIMT after adjusting for confounding factors. CONCLUSIONS: The ICAS response may be associated with the CIMT response to medical treatment.
Atherosclerosis ; Carotid Intima-Media Thickness* ; Constriction, Pathologic ; Follow-Up Studies ; Humans ; Intracranial Arteriosclerosis* ; Logistic Models ; Magnetic Resonance Angiography ; Stroke ; Tetrazoles

Enteropathy-type T-cell lymphoma (ETL) or enteropathy-associated T-cell lymphoma is a very rare malignant intestinal tumor. ETL is usually diagnosed by surgery. Endoscopic findings of ETL are not well known, and there are few reports of findings from endoscopy that has been performed only using white light. Additionally, there are no definite treatment guidelines for ETL. Therefore, we report a case of ETL diagnosed by enteroscopy with imaging-enhanced endoscopy and also review recently developed treatment options.
Endoscopy ; Enteropathy-Associated T-Cell Lymphoma ; Humans ; Light ; Lymphoma, T-Cell ; T-Lymphocytes

BACKGROUND AND PURPOSE: Stroke requires consistent care, but there is concern over the "weekend effect", whereby a weekend admission results in a poor outcome. Our aim was to determine the impact of weekend admission on clinical outcomes in patients with acute ischemic stroke in Korea. METHODS: The outcomes of patients admitted on weekdays and weekends were compared by analyzing data from a prospective outcome registry enrolling 1247 consecutive patients with acute ischemic stroke admitted to four neurology training hospitals in South Korea between September 2004 and August 2005. The primary outcome was a poor functional outcome at 3 months, defined as modified Rankin Scale (mRS) of 3-6. Secondary outcomes were 3-month mortality, use of thrombolysis, complication rate, and length of hospitalization. Shift analysis was also performed to compare overall mRS distributions. RESULTS: On weekends, 334 (26.8%) patients were admitted. Baseline characteristics were comparable between the weekday and weekend groups except for more history of heart disease and shorter admission time in weekend group. Univariate analysis revealed poor functional outcome at 3 months, 3-month mortality, complication rate, and length of hospitalization did not differ between the two groups. In addition, overall mRS distributions were comparable (p=0.865). After adjusting for baseline factors and stroke severity, weekend admission was not associated with poor functional outcome at 3 months (adjusted odds ratio, 1.05; 95% CI, 0.74-1.50). Furthermore, none of secondary endpoints differed between the two groups in multivariate analysis. CONCLUSIONS: Weekend admission was not associated with poor functional outcome than weekday admission in patients with acute ischemic stroke in this study. The putative weekend effect should be explored further by considering a wider range of hospital settings and hemorrhagic stroke.
Heart Diseases ; Hospitalization ; Humans ; Neurology ; Odds Ratio ; Prospective Studies ; Republic of Korea ; Stroke

BACKGROUND AND PURPOSE: Disability-adjusted life years (DALY), incorporating both disability and mortality, has been widely employed to measure regional and global burdens of stroke. Thus far, the DALY lost to stroke in a population has been estimated using only the crude population-level data; no previous study has incorporated refined data from stroke registries. The aim of this study was to integrate the stroke registry data and the population-level incidence data to project the nationwide DALY lost to ischemic stroke. METHODS: From the data of two large ischemic stroke registries, we derived an average DALY lost due to ischemic stroke for each of the following age groups: <45, 45-54, 55-64, 65-74, 75-84, and > or =85 years. The nationwide ischemic stroke incidence for each age group was extracted from a cardiovascular and cerebrovascular surveillance study that analyzed the 2004 Korean Health Insurance database. RESULTS: The average DALY lost due to ischemic stroke for the age groups <45, 45-54, 55-64, 65-74, 75-84, and > or =85 years was 5.07, 4.63, 4.35, 3.88, 2.88, and 1.73, respectively. By multiplying the incidence and the average DALY lost, the nationwide DALY lost was determined to be 9,952 for those <45 years, 24,608 for 45-54 years, 50,682 for 55-64 years, 88,875 for 65-74 years, 52,089 for 75-84 years, and 8,192 for > or =85 years, respectively. The projected nationwide DALY lost due to 64,688 ischemic strokes in 2004 was 234,399 (121,482 for men and 113,244 for women), and the DALY lost per 100,000 person-years was 483 (500 for men and 469 for women). CONCLUSIONS: Incidence data from a population study and DALY values derived from stroke registries can be integrated to provide a more refined projection of the nationwide burden of ischemic stroke. In Korea, more than 230,000 years of healthy life are being lost annually due to ischemic stroke, and hence prompt action is imperative.
Humans ; Incidence ; Insurance, Health ; Korea ; Male ; Registries ; Stroke

BACKGROUND: The aim of study was to determine the relative frequency of malignant lymphoma according to World Health Organization (WHO) classification in Korea. METHODS: A total of 3,998 cases diagnosed at 31 institutes between 2005 and 2006 were enrolled. Information including age, gender, pathologic diagnosis, site of involvement and immunophenotypes were obtained. RESULTS: The relative frequency of non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (HL) was 95.4% and 4.6%, respectively. B-cell lymphomas accounted for 77.6% of all NHL, while T/natural killer (T/NK)-cell lymphomas accounted for 22.4%. The most frequent subtypes of NHL were diffuse large B-cell lymphoma (42.7%), extranodal marginal zone B-cell lymphoma (MZBCL) of mucosa-associated lymphoid tissue (19.0%), NK/T-cell lymphoma (6.3%) and peripheral T-cell lymphoma (PTCL), unspecified (6.3%), in decreasing order. The relative frequency of HL was nodular sclerosis (47.4%), mixed cellularity (30.6%), and nodular lymphocyte predominant (12.1%) subtypes. Compared with a previous study in 1998, increase in gastric MZBCL and nodular sclerosis HL, and slight decrease of follicular lymphoma, PTCL, and NK/T-cell lymphoma were observed. CONCLUSIONS: Korea had lower rates of HL and follicular lymphoma, and higher rates of extranodal NHL, extranodal MZBCL, and NK/T-cell lymphoma of nasal type compared with Western countries. Changes in the relative frequency of lymphoma subtypes are likely ascribed to refined diagnostic criteria and a change in national health care policy.
Academies and Institutes ; Delivery of Health Care ; Hodgkin Disease ; Korea ; Lymphocytes ; Lymphoid Tissue ; Lymphoma ; Lymphoma, B-Cell ; Lymphoma, B-Cell, Marginal Zone ; Lymphoma, Follicular ; Lymphoma, Non-Hodgkin ; Lymphoma, T-Cell, Peripheral ; Sclerosis ; World Health Organization