Characteristics and management of stroke in Korea: 2014–2018 data from Korean Stroke Registry

2019 ◽  
Vol 15 (6) ◽  
pp. 619-626 ◽  
Author(s):  
Han-Yeong Jeong ◽  
Keun-Hwa Jung ◽  
Heejung Mo ◽  
Chan-Hyuk Lee ◽  
Tae Jung Kim ◽  
...  
Keyword(s):  
Risk Factors ◽  
Reperfusion Therapy ◽  
Lifestyle Changes ◽  
Large Artery ◽  
Stroke Subtype ◽  
Vessel Occlusion ◽  
Stroke Registry ◽  
Aging Populations ◽  
Care Patterns ◽  
Ischemic Attack

Background Lifestyle changes and evolving healthcare practices in Korea have influenced disease patterns and medical care. Since strokes have high disease burden in countries with aging populations, it is necessary to evaluate the associated recent disease characteristics and patient care patterns. The Korean Stroke Registry is a nationwide, multicenter, prospective, hospital-based stroke registry in Korea used to monitor these changes across the population. Aims We aimed to evaluate the recent status of clinical characteristics and management of stroke cases in order to identify changes in the Korean population across time. Methods This study used Korean Stroke Registry data from patients experiencing ischemic stroke or transient ischemic attack patients, between 2014 and 2018. We analyzed data on demographics, risk factors, stroke subtypes, and treatments that included thrombolysis. Results A total of 39,291 patients (mean age 68.0 ± 13.0, 58.3% male) were analyzed. The proportions of hypertension, diabetes mellitus, dyslipidemia, atrial fibrillation, and prior stroke were 63.4%, 30.9%, 27.7%, 19.4%, and 17.1%, respectively. In the stroke subtype analysis, the frequency of large artery atherosclerosis was highest (32.6%), followed by cardioembolism (21.3%) and small vessel occlusion (19.9%). Acute reperfusion therapy was conducted in 15.3% of cases (11.7% using intravenous tPA and 7.3% using intra-arterial thrombectomy). Intra-arterial thrombectomy also demonstrated a steep increasing trend over time (RR 1.095 (1.060–1.131), p < 0.001). Conclusions This study provided analysis of nationwide, hospital-based, quality-controlled data from the Korean Stroke Registry database regarding changes in the characteristics, risk factors, and treatments of strokes in Korea.

Causes of Death in Different Subtypes of Ischemic and Hemorrhagic Stroke

Angiology ◽  
2017 ◽  
Vol 69 (7) ◽  
pp. 582-590 ◽  
Author(s):  
Chi-Hung Liu ◽  
Jr-Rung Lin ◽  
Chia-Wei Liou ◽  
Jiann-Der Lee ◽  
Tsung-I Peng ◽  
...  
Keyword(s):  
Cause Of Death ◽  
Causes Of Death ◽  
Hemorrhagic Stroke ◽  
First Year ◽  
Large Artery ◽  
Stroke Subtype ◽  
Vessel Occlusion ◽  
Cancer History ◽  
Stroke Registry ◽  
Undetermined Etiology

Causes of death in both ischemic stroke (IS) and hemorrhagic stroke (HS) subtypes are not comprehensively studied. Between 2008 and 2011, we enrolled 11 215 first-ever stroke patients from the Stroke Registry of Chang-Gung Healthcare System and linked these data to the national death registry. The main causes of death in each stroke subtype were assessed. Patients with HS had higher overall mortality than IS (32.0% vs 18.1%, P < .001). In IS subtypes, large-artery atherosclerosis plus cardioembolism had the worst mortality (40.7%, P < .001). Stroke was the leading cause of death in both IS and HS within the first year. Stroke remained the major cause of death in HS, but cancer was the leading cause of death in IS after the first year. After excluding the patients with previous cancer history, cancer was still an important cause of death in IS and HS, particularly in the IS subtypes of small vessel occlusion, stroke of undetermined etiology, and transient ischemic attack.

Abstract TP227: Vascular Calcification, Atherosclerosis Burden, and Stroke Mechanism in Ischemic Stroke

Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
Takashi Shimoyama ◽  
Kunio Nakamura ◽  
Sibaji Gaj ◽  
Shivakrishna Kovi ◽  
Ken Uchino
Keyword(s):  
Ischemic Stroke ◽  
Large Artery ◽  
Stroke Patients ◽  
Stroke Subtype ◽  
Vessel Occlusion ◽  
Stroke Registry ◽  
Stroke Subtypes ◽  
Toast Classification ◽  
Stroke Mechanism ◽  
Post Hoc

Background and Purpose: Calcification of the intracranial carotid artery is recognized as a risk factor for stroke in the general population. The significance of vascular calcifications in its relationship stroke mechanisms is incompletely understood. We hypothesized that vascular calcium quantification using CT angiography (CTA) can differ by stroke mechanism among ischemic stroke patients. Methods: From a prospective single-hospital stroke registry from 2018, we identified ischemic stroke patients who underwent CTA. Automatic artery and calcification segmentation method measured calcification volumes in the intracranial, extracranial, and aortic arteries using deep-learning U-net model and region-grow algorithms. Stroke subtypes were diagnosed based on the TOAST classification: large artery atherosclerosis (LAA), small vessel occlusion (SVO), cardioembolism (CE), others/undetermined. We evaluated the relationship between CTA calcification volume and stroke subtypes on one-way ANOVA and Tukey’s post-hoc test. Results: Of the 558 consecutive acute ischemic stroke patients, we enrolled 388 patients (212 males; mean age 66.6 years) in the study. Others/undetermined (34.8%) was the most frequent stroke subtype, followed by CE (29.4%), LAA (25.5%), and SVO (10.3%). The overall prevalence of atherosclerotic calcification was 95.9% in stroke patients. LAA had significantly higher calcification volume with 809 mm 3 compared to SVO (390 mm 3 , P=0.040), others/undetermined (300 mm 3 , P=0.001), but not CE (860 mm 3 , P=0.958). In age < 65 years subset, LAA showed higher calcification volume with 567 mm 3 than SVO (176 mm 3 , P=0.014), CE (213 mm 3 , P=0.021) and others/undetermined (180 mm 3 , P<0.001). There were no significant differences in calcification volume among stroke subtypes in age ≥65 years. Conclusion: Atherosclerotic calcium burden with a quantitative analysis of CTA images may be useful to differentiate stroke mechanism in younger patients.

Patient Demographics, Characteristics, and Intrahospital Mortality of Different Ischemic Stroke Subtypes in a Tertiary Hospital during Five-Year Period

2021 ◽  
Vol 6 (1) ◽  
pp. 6
Author(s):  
Sintija Strautmane ◽  
Kristaps Jurjāns ◽  
Estere Zeltiņa ◽  
Evija Miglāne ◽  
Andrejs Millers
Keyword(s):  
Risk Factors ◽  
Ischemic Stroke ◽  
Reperfusion Therapy ◽  
Cardioembolic Stroke ◽  
Study Group ◽  
Large Artery ◽  
Patient Demographics ◽  
Stroke Subtypes ◽  
Female Predominance ◽  
Study Population

Background and Objectives. Ischemic stroke (IS) is one of the leading causes of disability, morbidity, and mortality worldwide. The goal of the study was to evaluate patient demographics, characteristics, and intrahospital mortality among different ischemic stroke subtypes. Materials and Methods. A retrospective observational non-randomized study was conducted, including only ischemic stroke patients, admitted to Pauls Stradins Clinical university hospital, Riga, Latvia, from January of 2016 until December 2020. Ischemic stroke subtypes were determined according to Trial of Org 10172 in Acute Stroke Treatment (TOAST) criteria as a stroke due to (1) large-artery atherosclerosis (atherothrombotic stroke (AS)), (2) cardioembolism (cardioembolic stroke (CS)), (3) small-vessel occlusion (lacunar stroke (LS)), (4) stroke of other determined etiology (other specified stroke (OSS)), and (5) stroke of undetermined etiology (undetermined stroke (US)). The data between different stroke subtypes were compared. Results. There was a slight female predominance among our study population, as 2673 (56.2%) patients were females. In our study group, the most common IS subtypes were cardioembolic stroke (CS), 2252 (47.4%), and atherothrombotic stroke (AS), 1304 (27.4%). CS patients were significantly more severely disabled on admission, 1828 (81.4%), and on discharge, 378 (16.8%), p < 0.05. Moreover, patients with CS demonstrated the highest rate of comorbidities and risk factors. This was also statistically significant, p < 0.05. Differences between the total patient count with no atrial fibrillation (AF), paroxysmal AF, permanent AF, and different IS subtypes among our study population demonstrated not only statistical significance but also a strong association, Cramer’s V = 0.53. The majority of patients in our study group were treated conservatively, 3389 (71.3%). Reperfusion therapy was significantly more often performed among CS patients, 770 (34.2%), p < 0.05. The overall intrahospital mortality among our study population was 570 (12.0%), with the highest intrahospital mortality rate noted among CS patients, 378 (66.3%), p < 0.05. No statistically significant difference was observed between acute myocardial infarction and adiposity, p > 0.05. Conclusions. In our study, CS and AS were the most common IS subtypes. CS patients were significantly older with slight female predominance. CS patients demonstrated the greatest disability, risk factors, comorbidities, reperfusion therapy, and intrahospital mortality.

Abstract 82: Differences Between Caucasians and Asians in Intracranial Arterial Stenosis Among TIA and Minor Stroke Patients: Comparisons of Two Contemporary Cohorts

Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
Xinyi Leng ◽  
Robert Hurford ◽  
Xueyan Feng ◽  
Ka Lung Chan ◽  
Linxin Li ◽  
...  
Keyword(s):  
Risk Factors ◽  
Ct Angiography ◽  
Interobserver Agreement ◽  
Arterial Stenosis ◽  
Minor Stroke ◽  
Intracranial Arterial Stenosis ◽  
Stroke Patients ◽  
Stroke Registry ◽  
The Difference ◽  
Ischemic Attack

Background: Despite numerous reports indicating ethnic difference in intracranial arterial stenosis (ICAS) between Caucasians and Asians, there has been no direct comparison in disease burden and clinical correlates of ICAS in stroke patients in the two populations with the same criteria to define ICAS. Methods: Acute minor stroke or transient ischemic attack patients who received cerebral MR/CT angiography exam in two cohorts were analyzed: Oxford Vascular Study (OXVASC, 2011-2018) with predominantly Caucasians, and the Chinese University of Hong Kong (CUHK) stroke registry (2011-2015) with predominantly Chinese. ICAS was defined as ≥50% stenosis in any major intracranial artery in MR/CT angiography. Interobserver agreement between 2 investigators for presence of ICAS was assessed in 50 cases with Cohen’s kappa. We compared the burden and risk factors of ICAS in the two cohorts. Results: Overall, 1,287 patients from OXVASC (mean age 69 years) and 640 from the CUHK cohort (mean age 66 years) were analyzed. Interobserver agreement for presence of ICAS was good (kappa=0.82). Prevalence of ICAS was significantly higher in Chinese than in Caucasians: 43.6% in the CUHK cohort versus 20.0% in OXVASC (crude OR 3.10; age-adjusted OR 3.81, 95% CI 3.06-4.75; p<0.001). Mean ages of patients with ICAS in the two cohorts were 75 and 68 years, respectively. The difference between Caucasians and Chinese in ICAS prevalence was smaller in those aged ≥70 years (28.1% versus 51.9%) than those <70 years (9.8% versus 38.0%) (Figure). ICAS shared similar risk factors in the two cohorts, including older age, and history of hypertension and diabetes. Conclusions: Chinese are more susceptible to ICAS, with an earlier onset age than Caucasians, but the ICAS burden in Caucasians was higher than previously estimated, especially in older patients.

Abstract 3884: Stroke Subtypes in Hispanic Patients in the NINDS Stroke Genetics Network (SiGN): A Comparison of Two Classification Systems

Stroke ◽  
2012 ◽  
Vol 43 (suppl_1) ◽  
Author(s):  
Michael Katsnelson ◽  
Tatjana Rundek ◽  
Ralph Sacco ◽  
Hannah Gardener ◽  
Shaneela Malik ◽  
...  
Keyword(s):  
Risk Factors ◽  
Ischemic Stroke ◽  
Classification Systems ◽  
Blood Collection ◽  
Large Artery ◽  
Stroke Subtype ◽  
Reliable Determination ◽  
Stroke Treatment ◽  
Stroke Subtypes ◽  
Small Artery Occlusion

Objectives: Identification of gene variants of stroke subtypes is important for the development of tailored ischemic stroke therapies among various ethnic groups. Valid and reliable determination of ischemic stroke subtype is essential for achieving this goal and to standardize a classification scheme across multi-center studies and different populations. Causative Classification System for Ischemic Stroke (CCS) is a novel computerized subclassification tool developed to improve reliability and accuracy of classifying stroke types. The CCS algorithm relies on both phenotypic and causative stroke variables. A Hispanic subset of the SiGN, an important and distinct target population with greater risk of certain stroke subtypes, was evaluated with Trial of Org 10172 in Acute Stroke Treatment (TOAST) and CCS and the agreement between the two classification systems was analyzed. Methods: Over 6000 subjects at 15 sites across US and Europe were enrolled, with TOAST and CCS locally adjudicated. Blood collection and central data quality control (10% central readjudication) were performed on all participants. A subset of Hispanics was analyzed for the purpose of this study and the agreement between the TOAST and CCS were assessed by kappa statistic. Findings: Hispanics (n=595, 10.9%) compared to non-Hispanics (n=5457) were more likely to be younger (63.7 vs. 64.0), male (55% vs. 46%) and have fewer of the traditional stroke risk factors HTN (54% vs. 64%), Afib (11% vs. 14%), DM(23% vs. 25%), CAD(16% vs. 20%) and smoking(19% vs. 22%). While the TOAST showed no differences between stroke subtypes for Hispanic vs. non-Hispanics, in CCS, Hispanics were classified with more of large vessel (22% vs. 20%), cardioembolic (37% vs. 30%) and small vessel strokes (13% vs. 9%) and fewer with undetermined etiology (28% vs. 40%) as compared to non-Hispanics. TOAST and CCS offered moderate correlation across all stroke types in Hispanics: kappa of 0.66 for large artery atherosclerosis, 0.58 for cardioembolic, and 0.58 for small artery occlusion. Conclusion: CCS offers a more sensitive and accurate system for subphenotyping of strokes in Hispanics who tended to have relatively fewer risk factors and unclassified strokes. Further studies correlating the two classification systems and their relation to genotyping data are warranted.

Abstract 2919: Do Premature Ventricular Contractions Play a Role in the Etiologic Subtypes of Ischemic Stroke?

Stroke ◽  
2012 ◽  
Vol 43 (suppl_1) ◽  
Author(s):  
JUN LEE ◽  
Na-Young Kim
Keyword(s):  
Risk Factors ◽  
Ischemic Stroke ◽  
Cryptogenic Stroke ◽  
Holter Monitoring ◽  
Median Number ◽  
Large Artery ◽  
Vessel Occlusion ◽  
Premature Ventricular Contractions ◽  
Ordinal Logistic Regression Analysis ◽  
The Relationship

Background The relationship between stroke and non-atrial fibrillation cardiac arrhythmias remains unclear. Frequent premature ventricular contractions (PVCs) are associated with impaired ventricular relaxation and may increase the risk of clot formation and subsequent embolization. This study investigated the relationship between frequency of PVCs and etiologic subtypes of ischemic stroke. Methods Consecutive ischemic stroke patients admitted within 7 days of onset who underwent 24-hour Holter monitoring were enrolled (n=451). Subtypes of ischemic stroke were defined according to the SSS-TOAST classification as Large artery atherosclerosis (LAD), cardioembolic stroke (CE), small vessel occlusion (SVO), other causes (OC), and cryptogenic stroke (CS). Risk factors, demographic information, and 24-hour Holter recordings were compared between the subtypes of ischemic stroke. Results There were 182 women and 269 men (191 LAD, 90 CE, 93 SVO, 13 OC, 64 CS), with a mean age of 66 years (median 68). PVCs were seen in 305 patients (67.5%) on 24-hour Holter monitoring (median 3, IQR 0-48). CE had a higher median number of PVCs (median 24, IQR 0-258) than LAD (median 2, p=0.01), SVO (median 1, p<0.001), OC (median 0, p=0.013), and CS (median 4, p=0.2). The proportions of frequent PVCs (>50 in a 24-hour Holter monitoring) were higher in CE (43.3%) compared with the other groups (20.9% in LAD, 15.1% in SVO, 15.4% in OC, and 23.4% in CS; p<0.001). Compared with the SVO, the upper 3 quartiles of PVCs were associated with CE (OR 2.93; 95% CI, 1.69 to 5.06) and CS (OR 1.86; 95% CI, 1.07 to 3.2) in ordinal logistic regression analysis after adjustment for traditional risk factors. Conclusions The number of PVCs detected by 24-hour Holter monitoring is associated with CE and CS. The presence of high frequency of PVC may help in stratifying patients with different stroke subtypes, particularly embolic stroke. The role of these arrhythmias as a risk marker for ischemic stroke deserves further investigation.

Abstract WP49: Distal Hyperintense Vessels Were not a Predictor of Large Vessel Occlusion in Patients With Transient Ischemic Attack

Stroke ◽  
2016 ◽  
Vol 47 (suppl_1) ◽  
Author(s):  
Marcelo M de Figueiredo ◽  
Marcela R Vazzoller ◽  
Edson Amaro Jr ◽  
Renata A Miranda ◽  
Gisele S Silva
Keyword(s):  
Transient Ischemic Attack ◽  
Surrogate Marker ◽  
Multivariate Logistic Regression Analysis ◽  
Clinical Information ◽  
Large Vessel ◽  
Arterial Stenosis ◽  
Large Artery ◽  
Large Vessel Occlusion ◽  
Vessel Occlusion ◽  
Ischemic Attack

Introduction: Distal hyperintense vessels (DHV) detected by FLAIR imaging are not uncommon in patients with acute ischemic stroke. The presence of DHV and its predictors has been scarcely evaluated in patients with transient ischemic attack (TIA), being associated to the presence of large vessel occlusion in such patients. We assessed the hypothesis that DHV are frequent in patients with TIA and do correlate with relevant clinical and neuroimaging characteristics. Methods: We evaluated a database of consecutive patients admitted with TIA from February 2009 to June 2012 who had undergone magnetic resonance imaging within 30 h of symptoms onset and intracranial and extracranial vascular imaging. We analyzed the relationship between DHV, clinical presentation, risk factors, neuroimaging characteristics and large artery stenosis or occlusion. DHV signals were defined on FLAIR images as focal, linear or serpentine, hyperintense signals relative to gray matter. Two neuroradiologists blinded to clinical information reached consensus regarding the presence of DHV. Results: Seventy-two TIA patients were enrolled. The median time from symptoms onset to MRI was 8:39 h [4:21, 14:13]. DHV signals on FLAIR images were present in 12 (16.7 %) patients. The overall agreement between examiners was good (k 0.67). Patients with DHV had more atrial fibrillation (AF) than those without (41.7% versus 21.7%, p=0.05) and a trend towards more congestive heart failure (CHF) (8.3% versus 1.7%, p=0.2) and diabetes (41.7% versus 21.7%, p=0.1). There were no differences in the frequency of intracranial or cervical arterial stenosis, cerebral microbleeds and white matter abnormalities in patients with and without DHV. In a multivariate logistic regression analysis, only AF had a trend to be a predictor of DHV (OR=4.24, p=0.1). The statistical model to predict DHV including AF, diabetes, and CHF had a moderate fit in terms of discrimination (c statistic=0.62) Conclusion: DHV signals on FLAIR images occur in patients with TIA and might correlate with clinical variables like AF and not only with large vessel occlusion as previously described. The presence of DVH in patients with TIA and AF might be a surrogate marker for a previous large vessel occlusion spontaneously recanalized.

scholarly journals Effect of Edaravone on Neurological Symptoms in Real-World Patients With Acute Ischemic Stroke

Stroke ◽  
2019 ◽  
Vol 50 (7) ◽  
pp. 1805-1811 ◽  
Author(s):  
Susumu Kobayashi ◽  
Shingo Fukuma ◽  
Tatsuyoshi Ikenoue ◽  
Shunichi Fukuhara ◽  
Shotai Kobayashi ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Neurological Symptoms ◽  
Small Vessel ◽  
Large Artery ◽  
Stroke Subtype ◽  
Vessel Occlusion ◽  
Nihss Score ◽  
Ischemic Stroke Subtype ◽  
History Of

Background and Purpose— In Japan, nearly half of ischemic stroke patients receive edaravone for acute treatment. The purpose of this study was to assess the effect of edaravone on neurological symptoms in patients with ischemic stroke stratified by stroke subtype. Methods— Study subjects were 61 048 patients aged 18 years or older who were hospitalized ≤14 days after onset of an acute ischemic stroke and were registered in the Japan Stroke Data Bank, a hospital-based multicenter stroke registration database, between June 2001 and July 2013. Patients were stratified according to ischemic stroke subtype (large-artery atherosclerosis, cardioembolism, small-vessel occlusion, and cryptogenic/undetermined) and then divided into 2 groups (edaravone-treated and no edaravone). Neurological symptoms were evaluated using the National Institutes of Health Stroke Scale (NIHSS). The primary outcome was changed in neurological symptoms during the hospital stay (ΔNIHSS=NIHSS score at discharge−NIHSS score at admission). Data were analyzed using multivariate linear regression with inverse probability of treatment weighting after adjusting for the following confounding factors: age, gender, and systolic and diastolic blood pressure at the start of treatment, NIHSS score at admission, time from stroke onset to hospital admission, infarct size, comorbidities, concomitant medication, clinical department, history of smoking, alcohol consumption, and history of stroke. Results— After adjusting for potential confounders, the improvement in NIHSS score from admission to discharge was greater in the edaravone-treated group than in the no edaravone group for all ischemic stroke subtypes (mean [95% CI] difference in ΔNIHSS: −0.46 [−0.75 to −0.16] for large-artery atherosclerosis, −0.64 [−1.09 to −0.2] for cardioembolism, and −0.25 [−0.4 to −0.09] for small-vessel occlusion). Conclusions— For any ischemic stroke subtype, edaravone use (compared with no use) was associated with a greater improvement in neurological symptoms, although the difference was small (<1 point NIHSS) and of limited clinical significance.

Neurologic deterioration in patients with acute ischemic stroke or transient ischemic attack

Neurology ◽  
2020 ◽  
Vol 95 (16) ◽  
pp. e2178-e2191
Author(s):  
Tai Hwan Park ◽  
Jeong-Kon Lee ◽  
Moo-Seok Park ◽  
Sang-Soon Park ◽  
Keun-Sik Hong ◽  
...  
Keyword(s):  
Ischemic Stroke ◽  
Acute Ischemic Stroke ◽  
Prospective Observational Study ◽  
Stroke Onset ◽  
Large Artery ◽  
Stroke Subtype ◽  
Relative Risks ◽  
Neurologic Deterioration ◽  
Early Arrival ◽  
Ischemic Attack

ObjectiveTo improve epidemiologic knowledge of neurologic deterioration (ND) in patients with acute ischemic stroke (AIS).MethodsIn this prospective observational study, we captured ND prospectively in 29,446 patients with AIS admitted to 15 hospitals in Korea within 7 days of stroke onset. ND was defined as an increase in NIH Stroke Scale (NIHSS) score ≥2 (total), or ≥1 (motor or consciousness), or any new neurologic symptoms. Change in incidence rate after stroke onset, causes, factors associated with ND, modified Rankin Scale (mRS) score at 3 months and 1 year, and a composite of stroke, myocardial infarction, and all-cause death at 1 year were assessed.ResultsND occurred in 4,299 (14.6%) patients. The highest rate, 6.95 per 1,000 person-hours incidence, was within the first 6 hours, which decreased to 2.09 within 24–48 hours, and 0.66 within 72–96 hours after stroke onset. Old age, female sex, diabetes, early arrival, large artery atherosclerosis as a stroke subtype, high NIHSS scores, glucose level, systolic blood pressure, leukocytosis at admission, recanalization therapy, TIA without a relevant lesion, and steno-occlusion of relevant arteries were associated with ND. The causes were stroke progression (71.8%) followed by recurrence (8.5%). Adjusted relative risks (95% CI) for poor outcome (mRS 3–6) at 3 months and 1 year were 1.75 (1.70–1.80) and 1.70 (1.65–1.75), respectively. The adjusted hazard ratio (95% CI) for the composite event was 1.59 (1.45–1.74).ConclusionsND should be taken into consideration as a factor that may influence the outcome in acute ischemic stroke.

Sign in / Sign up

Export Citation Format

Share Document