A Multimodal Ensemble Deep Learning Model for Functional Outcome Prognosis of Stroke Patients / 대한뇌졸중학회지

Background@#and Purpose The accurate prediction of functional outcomes in patients with acute ischemic stroke (AIS) is crucial for informed clinical decision-making and optimal resource utilization. As such, this study aimed to construct an ensemble deep learning model that integrates multimodal imaging and clinical data to predict the 90-day functional outcomes after AIS. @*Methods@#We used data from the Korean Stroke Neuroimaging Initiative database, a prospective multicenter stroke registry to construct an ensemble model integrated individual 3D convolutional neural networks for diffusion-weighted imaging and fluid-attenuated inversion recovery (FLAIR), along with a deep neural network for clinical data, to predict 90-day functional independence after AIS using a modified Rankin Scale (mRS) of 3–6. To evaluate the performance of the ensemble model, we compared the area under the curve (AUC) of the proposed method with that of individual models trained on each modality to identify patients with AIS with an mRS score of 3–6. @*Results@#Of the 2,606 patients with AIS, 993 (38.1%) achieved an mRS score of 3–6 at 90 days post-stroke. Our model achieved AUC values of 0.830 (standard cross-validation [CV]) and 0.779 (time-based CV), which significantly outperformed the other models relying on single modalities: b-value of 1,000 s/mm2 (P<0.001), apparent diffusion coefficient map (P<0.001), FLAIR (P<0.001), and clinical data (P=0.004). @*Conclusion@#The integration of multimodal imaging and clinical data resulted in superior prediction of the 90-day functional outcomes in AIS patients compared to the use of a single data modality.

Pain Control and Sedation in Neuro Intensive Critical Unit

Neurocritical patients who can self-report pain use the 0-10 numerical rating scale (NRS, verbal or visual form). However, critically ill patients whose nervous systems cannot express pain use the behavioral pain scale (BPS) and the critical care pain observation tool (CPOT) behavioral pain assessment tools. These tools reveal pain-related changes in movement, facial expression, posture, and physiological indicators such as heart rate, blood pressure, and respiratory rate. In pain control, it is first essential to reduce unnecessary painkillers through non-drug therapy and maximize the effect of the administered analgesics. For nonneuropathic pain, narcotic analgesics such as fentanyl, hydromorphone, morphine, and remifentanil are administered intravenously. Gabapentin, pregabalin, and carbamazepine are recommended along with narcotic analgesics for neuropathic pain control. In addition, nonnarcotic analgesics for multi-modal analgesia are used to reduce the use of narcotic analgesics or the side effects of narcotic analgesics. In the intensive care unit (ICU), the sedation-agitation scale (SAS) and the Richmond agitation-sedation scale (RASS) are used to determine the depth of sedation to be maintained during shallow or deep sedation, considering the condition of the critically ill patient. When selecting sedatives for critically ill patients, preferentially consider nonbenzodiazepines such as propofol or dexmedetomidine rather than benzodiazepines such as midazolam or lorazepam. In addition, patients use painkillers or sedatives for over a week, and neurological changes or physiological dependence may occur. Therefore, clinicians should evaluate the critically ill patient’s condition, and sedatives and painkillers should be reduced or discontinued.

Reperfusion therapy in acute ischemic stroke

Until mid-2010, intravenous thrombolysis remains the only reperfusion therapy for acute ischemic stroke. In 2015, the five pivotal endovascular recanalization therapy (ERT) trials demonstrated that ERT improved the prognosis of acute ischemic stroke with large artery occlusion within 6 hours after onset. Currently, ERT has been established as a crucial acute ischemic stroke treatment option. The prognosis of acute ischemic stroke is known to be time-dependent. Several studies addressed that ERT expands the time window for reperfusion therapy; thereby, improving prognosis.Current Concepts: Recent randomized clinical trials revealed that ERT improved the outcome in patients even within the late time window of up to 24 hours of stroke onset. The trials enrolled participants who had target mismatch, defined as either clinical-core or perfusion-core mismatch, which prompted an update of the national guidelines in several countries. To select the patients with stroke who were eligible for ERT, advanced imaging tools could be recommended.Discussion and Conclusion: According to the updated ERT guidelines, stroke centers were recommended to establish an appropriate imaging protocol and strategy for patients with acute ischemic stroke who were within the late time window. Additionally, if ERT is further practiced nationally, more manpower and infrastructure for patients with stroke should be supported at the stroke center.

Changes in High-Density Lipoprotein Cholesterol and Risks of Cardiovascular Events: A Post Hoc Analysis from the PICASSO Trial / 대한뇌졸중학회지

Background@#and purpose Whether pharmacologically altered high-density lipoprotein cholesterol (HDL-C) affects the risk of cardiovascular events is unknown. Recently, we have reported the Prevention of Cardiovascular Events in Asian Patients with Ischaemic Stroke at High Risk of Cerebral Haemorrhage (PICASSO) trial that demonstrated the non-inferiority of cilostazol to aspirin and superiority of probucol to non-probucol for cardiovascular prevention in ischemic stroke patients (clinicaltrials.gov: NCT01013532). We aimed to determine whether on-treatment HDL-C changes by cilostazol and probucol influence the treatment effect of each study medication during the PICASSO study. @*Methods@#Of the 1,534 randomized patients, 1,373 (89.5%) with baseline cholesterol parameters were analyzed. Efficacy endpoint was the composite of stroke, myocardial infarction, and cardiovascular death. Cox proportional hazards regression analysis examined an interaction between the treatment effect and changes in HDL-C levels from randomization to 1 month for each study arm. @*Results@#One-month post-randomization mean HDL-C level was significantly higher in the cilostazol group than in the aspirin group (1.08 mmol/L vs. 1.00 mmol/L, P<0.001). The mean HDL-C level was significantly lower in the probucol group than in the non-probucol group (0.86 mmol/L vs. 1.22 mmol/L, P<0.001). These trends persisted throughout the study. In both study arms, no significant interaction was observed between HDL-C changes and the assigned treatment regarding the risk of the efficacy endpoint. @*Conclusions@#Despite significant HDL-C changes, the effects of cilostazol and probucol treatment on the risk of cardiovascular events were insignificant. Pharmacologically altered HDL-C levels may not be reliable prognostic markers for cardiovascular risk.

Acute Ischemic Stroke in Moyamoya Syndrome Associated with Thyrotoxicosis

BACKGROUND: A few cases of moyamoya syndrome associated with thyrotoxicosis have been reported. However, studies on the association of hyperthyroidism with moyamoya syndrome are insufficient. CASE REPORT: Here we report a case of hyperthyroidism associated with moyamoya syndrome in a 41-year-old woman with aphasia and right side weakness. Brain imaging revealed acute cerebral infarction of left middle cerebral artery territory and occlusion of bilateral distal internal carotid arteries. CONCLUSION: Antithyroid medication stabilized the patient's neurologic deterioration, suggesting that thyrotoxicosis could aggravate acute cerebral infarction caused by moyamoya syndrome.

Renal Cholesterol Embolism during Warfarin Treatment

Cholesterol embolization syndrome (CES) usually occurs after endovascular procedures, it may also occurs after using anticoagulants and thrombolytics. We report a case of 66-year-old man with sudden elevation of creatinine after using warfarin due to cortical infarction. Histologic examinations revealed a cholesterol cleft on the arcuate artery. We concluded it as warfarin induced atheroembolic renal disease. Careful observation of kidneys is necessary in the case of renal abnormalities after using anticoagulation, considering the possibility of cholesterol embolism due to anticoagulant therapy.

Impacts of Rapid Recanalization and Collateral Circulation on Clinical Outcome after Intraarterial Thrombolysis / 대한뇌졸중학회지

BACKGROUND AND PURPOSE: Rapid recanalization might improve clinical outcomes after intraarterial thrombolysis (IAT) for acute ischemic stroke patients with collateral circulation. We determined whether rapid recanalization and collateral circulation affect clinical outcomes after IAT. METHODS: We retrospectively evaluated the clinical and radiological data of 134 consecutive patients who underwent IAT for intracranial artery occlusion. The interval from symptom onset to recanalization after IAT (onset-to-recanalization time) as an estimate of the probability of good clinical outcome (modified Rankin scale 0-2) was calculated in patients with collateral circulation in the ischemic hemisphere, which was rated poor (0/1 American Society of Interventional and Therapeutic Neuroradiology criteria) or good (2-4). Changes in National Institute of Health Stroke Scale (NHISS) score before and after IAT and modified Rankins scale scores 3 months after discharge were compared with respect to onset-to-recanalization time. RESULTS: In patients with good collateral circulation, the estimated onset-to-recanalization time for a 0.5 probability of a good clinical outcome was 347 minutes; with poor collateral circulation, it was 172 minutes for a 0.2 probability of good clinical outcome. Outcome analyses according to onset-to-recanalization time showed patients recanalized 6 hours of onset-to-recanalization time, and non-recanalization: 5.1, 6.9, 11.9, and 19.8, respectively) at discharge and higher percentages of good clinical outcome (69%, 66.7%, 21.9%, and 0%, respectively) 3 months after IAT. CONCLUSIONS: The time window to expect a high probability of a good clinical outcome after IAT is highly dependent on the collateral circulation.

Smoking is Not a Good Prognostic Factor following First-Ever Acute Ischemic Stroke / 대한뇌졸중학회지

BACKGROUND AND PURPOSE: There is evidence that smoking increases stroke risk; however, the effect of smoking on functional outcome after stroke is unclear. The aim of this study was to explore the effect of smoking status on outcome following acute ischemic stroke. METHODS: We assessed 1,117 patients with first-ever acute cerebral infarction and no prestroke disability whose functional outcome was measured after three months. A poor outcome was defined as a modified Rankin Scale score of > or =2. Smoking within one month prior to admission was defined as current smoking. Our analysis included demographics, vascular risk factors, initial National Institutes of Health Stroke Scale (NIHSS) score, stroke subtype, onset-to-admission time, thrombolytic therapy, initial blood pressure, and prognostic blood parameters as covariates. RESULTS: At baseline, current smokers were predominantly male, approximately 10 years younger than non-smokers (mean age, 58.6 vs. 68.3 years), and less likely to have hypertension and atrial fibrillation (53.9% vs. 65.4% and 8.7% vs. 25.9%, respectively), with a lower mean NIHSS score (4.6 vs. 5.7). The univariate analyses revealed that current smokers had a better functional outcome and significantly fewer deaths at three months follow-up when compared with non-smokers (functional outcome: 64.0% vs. 58.4%, P=0.082; deaths: 3.0% vs. 8.4%, P=0.001); however, these effects disappeared after adjusting for covariates (P=0.168 and P=0.627, respectively). CONCLUSIONS: In this study, smoking was not associated with a good functional outcome, which does not support the paradoxical benefit of smoking on functional outcome following acute ischemic stroke.

Reversible Encephalopathy Caused by Reactive Hypereosinophilia due to Toxocariasis

A 69-year-old male admitted to the psychological department due to delusion. One week later, he developed pneumonia and deep drowsy mental status. Despite improvement of pneumonia, his mental status got worse and he was referred to neurological department. The complete blood count tests showed repeated hypereosinophilia. The serologic tests revealed toxocariasis. He was treated with steroid and albendazole and his mental state rapidly improved. Toxocariasis is a common cause of reactive hypereosinophilia, which may be an underestimated etiology of reversible encephalopathy.

The Response of Carotid Intima-Media Thickness to Medical Treatment Is Correlated with That of Intracranial Atherosclerosis

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.

Validity and Reliability of a Korean Version of the National Institutes of Health Stroke Scale

BACKGROUND AND PURPOSE: The National Institutes of Health Stroke Scale (NIHSS) is a clinical assessment tool that is widely used in clinical trials and practice to evaluate stroke-related neurological deficits. The aim of this study was to determine the validity and reliability of the Korean version of the NIHSS (K-NIHSS) for evaluating Korean stroke patients. METHODS: The K-NIHSS was translated and adapted with regard to cultural and linguistic peculiarities. To examine its content validity, we quantified the Content Validity Index (CVI), which was rated by 11 stroke experts. The validity of the K-NIHSS was assessed by comparison with the Glasgow Coma Scale (GCS), the modified Rankin Scale (mRS), and the Barthel Index. The reliability of the K-NIHSS was evaluated using the unweighted kappa statistics for multiple raters and an intraclass correlation coefficient (ICC). RESULTS: The CVI of the K-NIHSS reached 0.91-1.00. The median K-NIHSS score at baseline was 3 (interquartile range, 2-7), and the mean+/-SD score was 6.0+/-6.6. The baseline K-NIHSS had a significantly negative correlation with the GCS at baseline and the Barthel Index after 90 days. The K-NIHSS also had a significantly positive correlation with the mRS after 90 days. Facial paresis and dysarthria had moderate interrater reliability (unweighted kappa, 0.41-0.60); kappa values were substantial to excellent (unweighted kappa, >0.60) for all the other items. The ICC for the overall K-NIHSS score was 0.998. The intrarater reliability was acceptable, with a median kappa range of 0.524-1.000. CONCLUSIONS: The K-NIHSS is a valid and reliable tool for assessing neurological deficits in Korean acute stroke patients.

Successful Treatment of Intractable Hiccup with Levetiracetam

Hiccups may be considered a form of myoclonus of diaphragm. Valproic acid has been considered the drug of choice in treatment of intractable hiccups; however, its various adverse events limit its use in the clinical basis, especially in elderly or complicated patients. Levetiracetam was known as a safe antiepileptic drug. However, the anti-hiccup property of the levetiracetam has been rarely reported. We report a 69-year old male patient who developed sudden persistent hiccups and was successfully treated with levetiracetam. Levetiracetam should be considered as alternative treatment option in selected patients with intractable hiccups.

Successful Treatment of Intractable Hiccup with Levetiracetam / 대한간질학회지

Hiccups may be considered a form of myoclonus of diaphragm. Valproic acid has been considered the drug of choice in treatment of intractable hiccups; however, its various adverse events limit its use in the clinical basis, especially in elderly or complicated patients. Levetiracetam was known as a safe antiepileptic drug. However, the anti-hiccup property of the levetiracetam has been rarely reported. We report a 69-year old male patient who developed sudden persistent hiccups and was successfully treated with levetiracetam. Levetiracetam should be considered as alternative treatment option in selected patients with intractable hiccups.

The Factors Associated with the Decision of r-tPA Use in Acute Ischemic Stroke Patients Aged 80 Years or Older / 대한뇌졸중학회지

BACKGROUND: Small proportions of all the elderly stroke patients receive recombinant tissue plasminogen activator (r-tPA) therapy, although old age is not a proven contraindication to intravenous thrombolytic therapy for acute ischemic stroke. The purpose of this study was to identify reasons for exclusion from r-tPA therapy and factors associated with the decision of r-tPA use in elderly patients with acute ischemic stroke. METHODS: From the acute stroke registries of 22 domestic university hospitals taking the r-tPA therapy from January 2007 to May 2010, we extracted data of all acute ischemic stroke patients who were aged 80 or over and arrived within onset 3 hours. For all patients, we assessed the eligibility of r-tPA therapy using National Institute of Neurological Disorders and Stroke (NINDS) r-tPA trial criteria. For eligible patients, we compared all clinical variables between patients who were treated with r-tPA and those who were not, and analyzed potential factors related to the decision of r-tPA use. RESULTS: A total of 494 patients were included in this study. 255 patients (51.6%) were excluded by NINDS r-tPA trial criteria and the major reasons for exclusion were minor neurological deficit (53.7%) and clinical improvement (17.3%). Among 239 patients who were eligible for r-tPA, 162 (32.8%) patients received r-tPA and 77 (15.6%) did not. Multivariable analysis showed that younger age, shorter time-delay from onset to admission, non-smoker, no history of prior stroke, good pre-stroke functional status and severe initial neurological deficit were independently associated with the decision of r-tPA use in the elderly stroke patients predictors for r-tPA treatment. CONCLUSION: In very elderly patients, mild neurological deficit on arrival and rapid clinical improvement in neurological symptoms were the main reasons for exclusion from thrombolytic therapy.

Clinical Characteristics of Acute Ischemic Stroke while Sleep and Awake / 대한뇌졸중학회지

BACKGROUND: Ischemic stroke occurring during sleep is still an unexplored area of cerebrovascular event. As the exact onset time of stroke while sleeping (SWS) cannot be determined, these patients are generally excluded from the thrombolytic therapy of acute ischemic stroke. The aim of this study was to know whether differences in clinical features exist between patients suffering a SWS and those with stroke while awake (SWA). METHODS: We reviewed the medical records of acute ischemic stroke patients consecutively registered in Hallym Stroke Databank between January 1999 and June 2007. We compared the risk factors and clinical features between the SWS and SWA groups. RESULTS: A total of 2,962 patients were included in the study, of which 821 (27.7%) were SWS. No differences between SWS and SWA were identified with regard to baseline clinical characteristics and risk factors except a history of smoking. In stroke subtype, small vessel occlusions were more frequently in SWS group than SWA group. Intravenous rt-PA treatments were performed frequently in the SWA group. Clinical outcomes at discharge were better in SWA group than SWS group. CONCLUSION: This study suggest that no major differences were exist in clinical characteristics between SWS and SWA patients, except the history of smoking. Clinical outcomes of patients with ischemic stroke within 6 hours after stroke onset were poor in SWS group. In SWS group, relatively little chances of thrombolysis might be the explanation of these finding.

Immediate Anticoagulation for Acute Cardioembolic Stroke is Still Popular in Selective Cases in Korea / 대한뇌졸중학회지

BACKGROUND: Although current guidelines do not recommend immediate anticoagulation therapy (IAC) for acute ischemic stroke, judicious debates are still lingering on whether it might be done for acute cardioembolic stroke (ACES). We surveyed current practice patterns of anticoagulation therapy for ACES in Korea, and analyzed their related factors. METHODS: Using a web-based system, all neurology staffs of training hospitals in Korea surveyed about when and how they commenced anticoagulation therapy in the hypothetical cases with ACES. RESULTS: Of the 359 subjects invited, 281 responded to the e-mail, of whom 76 abstained from participating. The number of participants was therefore 205 (57.1%). Although a few physicians (4.4%) always performed IAC and some (10.7%) never did, most physicians made different decisions according to infarct size and presence of hemorrhagic transformation (HTr): IAC was performed more often in cases with medium-sized or small infarct than large one (68.2% vs. 35.9%, P<0.001), and in cases without HTr (68.6% vs. 34.9%, P<0.001). The most common method of administration was 'heparin followed by warfarin' (68.2%), and then 'warfarin alone' or 'warfarin with aspirin'. If IAC was not commenced, it resumed most commonly between 1 and 2 weeks after the onset (44.0%). CONCLUSION: Quite many neurologists in Korea did IAC in selective ACES, e.g. small sized infarction without HTr. Further studies are needed to prove the efficacy of IAC therapy in this selective population.

Establishment of a Korean Hepatitis B Surface Antigen Low Titer Performance Panel for Performance Validation of Hepatitis B Surface Antigen Immunoassays / 대한수혈학회지

BACKGROUND: A range of well characterized materials are needed for validating the performance of hepatitis B surface antigen (HBsAg) immunoassays. These materials are purchased currently from overseas manufacturers at a high cost and with limited quantity. This study was conducted to establish an HBsAg low titer performance panel for use as a national standard for validation of HBsAg immunoassays in Korea. METHODS: 476 plasma units reactive on blood donor screening were collected HBsAg was tested using 3 enzyme immunoassays (EIA) and 1 chemiluminescence immunoassay (CIA). Units reactive on the CIA assay or on 2 or more immunoassays were subjected to hepatitis B virus (HBV) DNA quantification, HBV genotyping and subtyping. Units reactive on HBV DNA quantification were confirmed for HBsAg by neutralization. Candidates for the panel were subjected to a collaborative study performed at 7 laboratories using 7 immunoassays. RESULTS: Eleven HBsAg positive units were selected for the low titer performance panel based on HBsAg immunoassay, HBV DNA quantification, HBV genotyping and subtyping results. The range of the HBsAg concentration of the panel members was 0.05~1.28 IU/mL. Two HBsAg negative units were also included as negative controls. CONCLUSION: As a result of this study, a low titer performance panel [KFDA standard (08/028); HBsAg low titer performance panel (BTRL HBV/LP)] for validation of HBsAg immunoassays has been established as a Korean national standard. Use of this panel will improve performance assessment of HBsAg immunoassays. Because the performance of immunoassays cannot be assessed properly with a limited number of panels, continuous efforts are needed to develop a range of performance panels.

Long-Term Outcomes of Acute Ischemic Stroke in Patients Aged 80 Years and Older

PURPOSE: Short life expectancy influences decision-making when treating very old patients with acute ischemic stroke (AIS). We investigated mortality and survival duration in very old AIS patients (> or =80 years) who received hospital care. PATIENTS AND METHODS: Mortality data were obtained from medical records, structured telephone inquiries, death certificates from the Korean National Statistical Office, and social security data 5+/-1.9 years after stroke onset. Age, gender, vascular risk factors, and functional outcomes from modified Rankin scales (MRS) at discharge were analyzed as predictors of mortality. RESULTS: Among 134 patients, 92 (68.7%) died. On Kaplan- Meier analysis, duration of survival of patients aged 80-84 years was longer than those aged 85-89 or 90-94 (24+/-6.4, 8+/-7.3, 7+/-2.0 months, respectively, p=0.002). Duration of survival of patients discharged in a state of MRS 0-1 was longer than the remaining groups at 47+/-4.8 months (p<0.001). In Cox proportional hazard analysis, age and MRS at discharge were independent predictors of mortality. CONCLUSION: Long-term outcomes of very old patients with AIS are not uniformly grave, therefore predictors of mortality and estimated duration of survival should be considered during decision- making for treatment.

The Meaning of Polysomnographic Indexes in Patients with Obstructive Sleep Apnea and Erectile Dysfunction / 대한남성과학회지

PURPOSE: The purpose of this study was to correlate erectile function with polysomnographic indexes of obstructive sleep apnea(OSA) and other associated factors. MATERIALS AND METHODS: Among the 42 patients who visited our sleep clinic, we enrolled 32 patients who scored lower than 22 on the IIEF-5(International Index of Erectile Function-5). Polysomnography(PSG) was performed for OSA evaluation. Apnea-hypopnea index(AHI), AHI during REM sleep, AHI during non-REM sleep, arousal index(AI), and sleep efficacy(SE) were used as PSG indexes. Obesity was quantified by body mass index(BMI). The patients were divided into 2 groups according to AHI: group A 10(n=19). BMI and erectile function scores were compared between the 2 groups. The correlations among erectile function scores, PSG indexes, and BMI were analyzed. RESULTS: IIEF-5 score was negatively correlated with AHI(r=-0.372, p <0.05) and AI(r=-0.472, p <0.05), and there was a positive correlation with SE(r=0.372, p <0.05) of PSG. Between the 2 AIH groups, the low AHI group had a statistically higher mean erectile function score, especially in the EF domain and in the total IIEF score compared to the high AHI group. CONCLUSIONS: Indexes for penile rigidity were negatively correlated with AHI and AI. These findings suggest that AHI, AI, and SE of PSG are meaningful indexes of erectile function and support the hypothesis that hypoxia induced by sleep apnea plays a role in poor rigidity. Further studies in larger groups, including analysis of PSG indexes and erectile function changes before and after the treatment of sleep apnea, would be necessary to confirm this hypothesis.

Analysis of 10,811 Cases with Acute Ischemic Stroke from Korean Stroke Registry: Hospital-Based Multicenter Prospective Registration Study

BACKGROUND: Although several hospital-based stroke studies were published, there has not been any reliable data representing the clinical characteristics of stroke in Korea. We analyzed the clinical characteristics of patients with ischemic stroke registered in the Korean Stroke Registry (KSR), which is the largest prospective hospital-based nation-wide stroke registry in Korea. METHODS: The KSR provided standardized protocols for collecting data, which includes the data of demographics, subtypes of stroke, risk factors, and neurological outcome at discharge. The brain imaging studies, including CT or MRI, were performed in all cases. RESULTS: KSR registered 10,811 patients of acute ischemic stroke between Nov. 2002 and Jun. 2004. The large-artery atherosclerosis was the most common subtype (37.3%), followed by small vessel occlusion (30.8%). Hypertension (65.4%) was the most common risk factor, followed by smoking (34.5%) and diabetes (28.3%). Although most of the hypertensive and diabetic patients had been diagnosed before the stroke, less than 45.4% and 32.5% of them were under regular control. The steno-occlusive lesion of extracranial carotid artery was only 29.3% and the ratio of intra- to extracranial artery disease was more than 2 in KSR. Only 20.5% of patients were admitted within 3 hours after stroke onset and 2.1% were treated with intravenous thrombolysis. In-hospital case-fatality was 5.2%, which is relatively comparable to those of previous studies. CONCLUSIONS: The KSR provided informative data in understanding the clinical characteristics of ischemic stroke in Korea. Further analysis of KSR will facilitate clinical trials and development of guidelines for the management of stroke patients.