No abstract

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 ≥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 ≥30 years of age, one in 3-4 has hypertension, one in 10 diabetes, and one in 7 hypercholesterolemia. One in 3 Korean adults ≥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.

Although there have been attempts to make clinical-MRI correlation in patients with lateral medullary infarction (LMI), studies with a large number of patients are unavailable. In this study, clinical features, MRI findings and angiogram results of 130 acute, consecutive patients with pure LMI were studied and correlated. MRI-identified lesions were classified rostro-caudally as rostral, middle and caudal, and horizontally as typical, ventral, large, lateral and dorsal. The distribution of horizontal subtypes was significantly different (P <0.001) among three rostro-caudal lesions in that rostral lesions tend to be ventral types and caudal lesions are lateral types. Patients with rostrally located lesions had dysphagia, facial paresis (P < 0.01, each) and dysarthria (P < 0.05) significantly more often, and severe gait ataxia and headache (P < 0.05, each) less often than those with caudal lesions. The frequencies of dysphagia (P < 0.01), dysarthria (P < 0.01) and bilateral trigeminal sensory pattern (P < 0.05) were significantly different among horizontal subtypes in that these symptoms were frequent in patients with "large type" as compared with those with lateral type lesions. Angiograms performed in 123 patients showed vertebral artery (VA) disease in 67% and posterior inferior cerebellar artery (PICA) disease in 10%. The presumed pathogenetic mechanisms included large vessel infarction in 50%, arterial dissection in 15%, small vessel infarction in 13% and cardiac embolism in 5%. Dissection occurred more often in patients with caudal (versus rostral) lesions (P < 0.01), whereas dorsal type infarcts (versus other types) were related more often to cardiogenic embolism and normal angiogram findings (P < 0.05, each). Patients with isolated PICA disease (versus those with VA disease) more often had cardiogenic embolism (P < 0.05) and less often had dissection (P < 0.01). It is concluded that rostro-caudal and horizontal classification of MRI helps us to understand the clinical and, partly, the aetiopathogenetic aspect of the heterogeneous LMI syndrome.