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.

Wall Shear Stress Associated with Stroke Occurrence and Mechanisms in Middle Cerebral Artery Atherosclerosis / 대한뇌졸중학회지

Background@#and Purpose Various mechanisms are involved in the etiology of stroke caused by atherosclerosis of the middle cerebral artery (MCA). Here, we compared differences in plaque nature and hemodynamic parameters according to stroke mechanism in patients with MCA atherosclerosis. @*Methods@#Consecutive patients with asymptomatic and symptomatic MCA atherosclerosis (≥50% stenosis) were enrolled. MCA plaque characteristics (location and plaque enhancement) and wall shear stress (WSS) were measured using high-resolution vessel wall and four-dimensional flow magnetic resonance imaging, respectively, at five points (initial, upstream, minimal lumen, downstream, and terminal). These parameters were compared between patients with asymptomatic and symptomatic MCA atherosclerosis with infarctions of different mechanisms (artery-to-artery embolism vs. local branch occlusion). @*Results@#In total, 110 patients (46 asymptomatic, 32 artery-to-artery embolisms, and 32 local branch occlusions) were investigated. Plaques were evenly distributed in the MCA of patients with asymptomatic MCA atherosclerosis, more commonly observed in the distal MCA of patients with artery-to-artery embolism, and in the middle MCA of patients with local branch occlusion. Maximum WSS and plaque enhancement were more prominent in the minimum lumen area of patients with asymptomatic MCA atherosclerosis or those with local branch occlusion, and were more prominent in the upstream area in those with artery-to-artery embolism. The elevated variability in the maximum WSS was related to stroke caused by artery-to-artery embolism. @*Conclusion@#Stroke caused by artery-to-artery embolism was related to plaque enhancement and the highest maximum WSS at the upstream point of the plaque, and was associated with elevated variability of maximum WSS.

High-on-Aspirin Platelet Reactivity Differs Between Recurrent Ischemic Stroke Associated With Extracranial and Intracranial Atherosclerosis

Background@#and Purpose Ischemic stroke recurs despite the use of antiplatelet agents. Various mechanisms are involved in recurrence due to intracranial atherosclerosis (ICAS) and extracranial atherosclerosis (ECAS). High-on-aspirin platelet reactivity (HAPR) may differ between recurrent stroke due to ICAS and ECAS. @*Methods@#Patients with recurrent ischemic stroke as a result of large-artery atherosclerosis despite taking aspirin were enrolled consecutively. Ischemic stroke was classified as stroke due to ICAS or ECAS according to the location of the culprit stenosis. An aspirin reaction units (ARU) value of >550 IU was defined as HAPR. HAPR and its associated factors were compared between the two groups and also considering the mechanism of stroke. @*Results@#Among the 190 patients with recurrent stroke (111 with ICAS and 79 with ECAS), 36 (18.3%) showed HAPR. The ARU value was higher in the ECAS than the ICAS group (492± 83 vs. 465±78, mean±standard deviation; p=0.028), as was the proportion of patients with HAPR (27.8% vs. 12.6%, p=0.008). Being male and having stroke due to ECAS (reference = stroke due to ICAS: odds ratio=5.760; 95% confidence interval=2.154–15.403; p<0.001) was independently associated with HAPR. The ARU value differed according to the stroke mechanism, and was highest in those with artery-to-artery embolism. Artery-to-artery embolism was independently associated with HAPR in both the ICAS and ECAS groups. @*Conclusions@#Recurrent stroke due to ECAS was more strongly associated with HAPR and insufficient antiplatelet inhibition than was that due to ICAS. Artery-to-artery embolism was associated with HAPR in recurrent ischemic stroke as a result of ICAS or ECAS.

Long-Term Changes in Post-Stroke Depression, Emotional Incontinence, and Anger / 대한뇌졸중학회지

Background@#and Purpose Long-term changes in post-stroke depression (PSD), post-stroke emotional incontinence (PSEI), and post-stroke anger (PSA) have rarely been studied. @*Methods@#This is a sub-study of EMOTION, a randomized, placebo-controlled trial, that examined the efficacy of escitalopram on PSD, PSEI, and PSA in patients with stroke. We interviewed patients at the long-term period (LTP) using predefined questionnaires: Montgomery-Åsberg depression rating scale (MADRS) for PSD, modified Kim’s criteria for PSEI, and Spielberger trait anger scale for PSA. Additionally, the ENRICHD Social Support Instrument (ESSI) for the social support state and the modified Rankin Scale (mRS) were measured. We investigated the changes in and factors behind PSD, PSEI, and PSA at LTP. @*Results@#A total of 222 patients were included, and the median follow-up duration was 59.5 months (interquartile range, 50 to 70). Compared to the data at 6 months post-stroke, the prevalence of PSEI (11.7% at 6 months, 6.3% at LTP; P=0.05) and mean anger score (21.62, 16.24; P<0.01) decreased, while the prevalence of PSD (35.6%, 44.6%; P=0.03) and mean MADRS (6.16, 8.67; P<0.01) increased at LTP. ESSI was associated with PSD and PSA, but not with PSEI. The effect of the baseline National Institutes of Health Stroke Scale score on PSD decreased over time. The effect of low social support on PSD was greater than that of mRS at LTP. @*Conclusions@#The prevalence and degree of PSD significantly increased, while those of PSEI and PSA decreased at LTP. PSD in this stage appeared to be more closely associated with a lack of social support than patients' physical disabilities.

Long-Term Changes in Post-Stroke Depression, Emotional Incontinence, and Anger / 대한뇌졸중학회지

Background@#and Purpose Long-term changes in post-stroke depression (PSD), post-stroke emotional incontinence (PSEI), and post-stroke anger (PSA) have rarely been studied. @*Methods@#This is a sub-study of EMOTION, a randomized, placebo-controlled trial, that examined the efficacy of escitalopram on PSD, PSEI, and PSA in patients with stroke. We interviewed patients at the long-term period (LTP) using predefined questionnaires: Montgomery-Åsberg depression rating scale (MADRS) for PSD, modified Kim’s criteria for PSEI, and Spielberger trait anger scale for PSA. Additionally, the ENRICHD Social Support Instrument (ESSI) for the social support state and the modified Rankin Scale (mRS) were measured. We investigated the changes in and factors behind PSD, PSEI, and PSA at LTP. @*Results@#A total of 222 patients were included, and the median follow-up duration was 59.5 months (interquartile range, 50 to 70). Compared to the data at 6 months post-stroke, the prevalence of PSEI (11.7% at 6 months, 6.3% at LTP; P=0.05) and mean anger score (21.62, 16.24; P<0.01) decreased, while the prevalence of PSD (35.6%, 44.6%; P=0.03) and mean MADRS (6.16, 8.67; P<0.01) increased at LTP. ESSI was associated with PSD and PSA, but not with PSEI. The effect of the baseline National Institutes of Health Stroke Scale score on PSD decreased over time. The effect of low social support on PSD was greater than that of mRS at LTP. @*Conclusions@#The prevalence and degree of PSD significantly increased, while those of PSEI and PSA decreased at LTP. PSD in this stage appeared to be more closely associated with a lack of social support than patients' physical disabilities.

Causes, Risk Factors, and Clinical Outcomes of Stroke in Korean Young Adults: Systemic Lupus Erythematosus is Associated with Unfavorable Outcomes

Background@#and Purpose: The incidence of ischemic stroke (IS) in young adults is increasing, and the associated large socioeconomic impact makes understanding IS in young adults important. We investigated the causes of and risk factors for IS in young adults, and their impact on outcomes. @*Methods@#The Stroke in Korean Young Adults (SKY) study is a standardized multicenter prospective study involving eight medical centers of the Republic of Korea. First-ever IS patients aged 18 years to 44 years were prospectively included in this study within 7 days of stroke onset.Their outcomes at 3 months were analyzed. @*Results@#This study enrolled 270 patients from April 2014 to December 2018, most (67.8%) of whom were male. About 41.5% of the patients had one or more vascular risk factors from among hypertension, diabetes mellitus, and dyslipidemia. However, only half of them had received regular treatment. Arterial dissection was more common in males, and systemic lupus erythematosus (SLE) and Moyamoya disease were more common in females. The outcome was favorable (modified Rankin Scale score of 0 or 1) in 81.9% of the patients at 3 months after stroke onset. More severe initial symptoms, higher initial glucose level, and SLE as a comorbidity were associated with unfavorable outcomes. @*Conclusions@#Young adult IS patients in Korea exhibit low awareness and poor management of their risk factors. Although the short-term outcome was relatively favorable in those patients, having SLE was associated with unfavorable outcomes. More attention needs to be paid for improving awareness and controlling risk factors in this population.

Clinical Characteristics of Non-Amnestic Mild Cognitive Impairment: A Single-Center Experience

BACKGROUND: To evaluate the clinical characteristics of patients with non-amnestic mild cognitive impairment (naMCI) in a memory disorder clinic at a single center. METHODS: A retrospective study was conducted involving 312 patients with naMCI from May 2011 to July 2018. Brain magnetic resonance imaging and detailed neuropsychological tests were performed in all patients. We used the proposed criteria for naMCI to classify the patients into single- and multiple-domain groups. We compared the baseline clinical characteristics, neuroimaging findings, and the rate of progression to dementia between these two groups. RESULTS: The 312 patients comprised 210 in the single-domain group (67.3%) and 102 in the multiple-domain group (32.7%). The mean age was significantly higher in the multiple-domain group than in the single-domain group. The years of education, mean Mini Mental State Examination score, and mean Clinical Dementia Rating Scale Sum of Boxes score were significantly lower in the multiple-domain group than in the single-domain group. The Z-scores of neuropsychological tests in most cognitive domains were significantly lower in the multiple-domain group than in the single-domain group. Compared to the single-domain group, the multiple-domain group showed more-severe medial temporal atrophy and contained a higher proportion of patients with moderate white-matter hyperintensities. Thirteen (8.4%) patients with naMCI progressed to dementia, most of who were diagnosed with Alzheimer's disease. CONCLUSIONS: We present a single-center experience of clinical characteristics in patients with naMCI. Close observation of the clinical profiles of patients with naMCI may help identify individuals at the greatest risk of dementia.

Differences in Therapeutic Responses and Factors Affecting Post-Stroke Depression at a Later Stage According to Baseline Depression / 대한뇌졸중학회지

BACKGROUND AND PURPOSE: The pathophysiology of post-stroke depression (PSD) is complex and may differ according to an individual’s mood immediately after stroke. Here, we compared the therapeutic response and clinical characteristics of PSD at a later stage between patients with and without depression immediately after stroke. METHODS: This study involved a post hoc analysis of data from EMOTION (ClinicalTrials.gov NCT01278498), a placebo-controlled, double-blind trial that examined the efficacy of escitalopram (10 mg/day) on PSD and other emotional disturbances among 478 patients with acute stroke. Participants were classified into the Baseline-Blue (patients with baseline depression at the time of randomization, defined per the Montgomery-Asberg Depression Rating Scale [MADRS] ≥8) or the Baseline-Pink groups (patients without baseline depression). We compared the efficacy of escitalopram and predictors of 3-month PSD (MADRS ≥8) between these groups. RESULTS: There were 203 Baseline-Pink and 275 Baseline-Blue patients. The efficacy of escitalopram in reducing PSD risk was more pronounced in the Baseline-Pink than in the Baseline-Blue group (p for interaction=0.058). Several risk factors differentially affected PSD development based on the presence of baseline depression (p for interaction < 0.10). Cognitive dysfunction was an independent predictor of PSD in the Baseline-Blue, but not in the Baseline-Pink group, whereas the non-use of escitalopram and being female were more strongly associated with PSD in the Baseline-Pink group. CONCLUSIONS: Responses to escitalopram and predictors of PSD 3 months following stroke differed based on the presence of baseline depression. Our data suggest that PSD pathophysiology is heterogeneous; therefore, different therapeutic strategies may be needed to prevent PSD emergence following stroke.

Ethnic Differences in Intracranial Artery Tortuosity: A Possible Reason for Different Locations of Cerebral Atherosclerosis / 대한뇌졸중학회지

No abstract available.

Basilar Artery Plaque and Pontine Infarction Location and Vascular Geometry / 대한뇌졸중학회지

BACKGROUND AND PURPOSE: Subclinical atherosclerotic plaques are common in patients with pontine infarctions (PIs) but without basilar artery (BA) stenosis. We hypothesized that BA plaque locations may differ by PI type and vertical location as well as vertebrobasilar artery geometry. METHODS: Ninety-six patients with PI but without BA stenosis on magnetic resonance imaging (MRI) and magnetic resonance angiography were enrolled. PIs were classified by type (paramedian, deep, or lateral) and vertical location (rostral, middle, or caudal). Patients underwent high-resolution MRI to evaluate BA plaque location (anterior, posterior, or lateral). The mid-BA angle on anteroposterior view and angle between the BA and dominant vertebral artery (BA-VA angle) on lateral view were measured. RESULTS: The PIs were paramedian (72.9%), deep (17.7%), and lateral (9.4%) type with a rostral (32.3%), middle (42.7%), and caudal (25.0%) vertical location. The BA plaque locations differed by PI type (P=0.03) and vertical location (P < 0.001); BA plaques were most frequent at the posterior wall in paramedian (37.1%) and caudal (58.3%) PIs and at the lateral wall in lateral (55.5%) and middle (34.1%) PIs. The BA-VA and mid-BA angles differed by BA plaque and PI vertical location; the greatest BA-VA angle was observed in patients with posterior plaques (P < 0.001) and caudal PIs (P<0.001). Greatest mid-BA angles were observed with lateral BA plaques (P=0.03) and middlelocated PIs (P=0.03). CONCLUSIONS: Greater mid-BA angulation may enhance lateral plaque formation, causing lateral and middle PIs, whereas greater BA-VA angulation may enhance posterior plaque formation, causing paramedian or caudal PIs.

Differences between the Molecular Mechanisms Underlying Ruptured and Non-Ruptured Carotid Plaques, and the Significance of ABCA1 / 대한뇌졸중학회지

BACKGROUND AND PURPOSE: Carotid plaques are a strong risk factor for ischemic stroke, and plaque rupture poses an even higher risk. Although many studies have investigated the pathogenic mechanisms of carotid plaque formation, few have studied the differences in molecular mechanisms underlying the rupture and non-rupture of carotid plaques. In addition, since early diagnosis and treatment of carotid plaque rupture are critical for the prevention of ischemic stroke, many studies have sought to identify the important target molecules involved in the rupture. However, a target molecule critical in symptomatic ruptured plaques is yet to be identified. METHODS: A total of 79 carotid plaques were consecutively collected, and microscopically divided into ruptured and non-ruptured groups. Quantitative polymerase chain reaction array, proteomics, and immunohistochemistry were performed to compare the differences in molecular mechanisms between ruptured and non-ruptured plaques. Enzyme-linked immunosorbent assay was used to measure the differences in ATP-binding cassette subfamily A member 1 (ABCA1) levels in the serum. RESULTS: The expression of several mRNAs and proteins, including ABCA1, was higher in ruptured plaques than non-ruptured plaques. In contrast, the expression of other proteins, including β-actin, was lower in ruptured plaques than non-ruptured plaques. The increased expression of ABCA1 was consistent across several experiments, ABCA1 was positive only in the serum of patients with symptomatic ruptured plaques. CONCLUSIONS: This study introduces a plausible molecular mechanism underlying carotid plaque rupture, suggesting that ABCA1 plays a role in symptomatic rupture. Further study of ABCA1 is needed to confirm this hypothesis.

Impairments of Inhibitory Motor Control in Cerebral Cortical Infarction

No abstract available.

Preoperative Coronary Stenosis Is a Determinant of Early Vascular Outcome after Carotid Endarterectomy

BACKGROUND AND PURPOSE: The benefit of carotid endarterectomy (CEA) is directly influenced by the risk of perioperative adverse outcomes. However, patient-level risks and predictors including coronary stenosis are rarely evaluated, especially in Asian patients. The aim of this study was to determine the relationship between the vascular risk factors underlying CEA, including coronary stenosis, and postoperative outcome. METHODS: One hundred and fifty-three consecutive CEAs from our hospital records were included in this analysis. All patients underwent coronary computed tomography angiography before CEA. Data were analyzed to determine the vascular outcomes in patients with mild-to-moderate vs. severe coronary stenosis and high vs. standard operative risk, based on the criteria for high operative risk defined in the Stenting and Angioplasty with Protection in Patients at High Risk for Endarterectomy (SAPPHIRE) trial. The vascular outcome was defined as the occurrence of postoperative (< or =30 days) stroke, myocardial infarction (MI), or death. RESULTS: An adverse vascular outcome occurred in 8 of the 153 CEAs, with 6 strokes, 2 MIs, and 3 deaths. The vascular outcome differed significantly between the groups with mild-to-moderate and severe coronary stenosis (p=0.024), but not between the high- and standard-operative-risk groups (stratified according to operative risk as defined in the SAPPHIRE trial). Multivariable analysis adjusting for potent predictors revealed that severe coronary stenosis (odds ratio, 6.87; 95% confidence interval, 1.20-39.22) was a significant predictor of the early vascular outcome. CONCLUSIONS: Severe coronary stenosis was identified herein as an independent predictor of an adverse early vascular outcome.

Early-stage Alcoholic Cerebellar Degeneration: Diagnostic Imaging Clues

No abstract available.

Sleep Disturbances and Predictive Factors in Caregivers of Patients with Mild Cognitive Impairment and Dementia

BACKGROUND AND PURPOSE: We examined the characteristics of sleep disturbances and sleep patterns in the caregivers of patients with amnestic mild cognitive impairment (aMCI) and dementia. METHODS: We prospectively studied 132 patients (60 with aMCI and 72 with dementia) and their caregivers, and 52 noncaregiver controls. All caregivers and controls completed several sleep questionnaires, including the Pittsburgh Sleep Quality Index (PSQI). The patients were administered neuropsychological tests and the neuropsychiatric inventory to evaluate their behavioral and neuropsychiatric symptoms of dementia (BPSD). RESULTS: The PSQI global score was 6.25+/-3.88 (mean+/-SD) for the dementia caregivers and 5.47+/-3.53 for the aMCI caregivers. The Insomnia Severity Index (ISI) and short form of the Geriatric Depression Scale (GDS-S) predicted higher PSQI global scores in aMCI caregivers, and higher scores for the ISI, Epworth Sleepiness Scale (ESS), and GDS-S in dementia caregivers. BPSD, including not only agitation, depression, and appetite change in dementia patients, but also depression, apathy, and disinhibition in aMCI patients, was related to impaired sleep quality of caregivers, but nighttime behavior was not. Age and gender were not risk factors for disturbed sleep quality. CONCLUSIONS: Dementia and aMCI caregivers exhibit impaired quality of sleep versus non-caregivers. ISI, GDS-S, and ESS scores are strong indicators of poor sleep in dementia caregivers. In addition, some BPSD and parts of the neuropsychological tests may be predictive factors of sleep disturbance in dementia caregivers.

Isolated Weakness of Radial-side Fingers Due to a Small Cortical Infarction

Predominant involvement of a particular group of fingers due to a central nervous system lesion has been described as pseudoperipheral palsy. Two patients visited our hospital with isolated weakness of a particular group of fingers due to small cortical infarctions. A 51-year-old woman suddenly developed weakness in her left index and middle fingers. The brain MRI showed a small infarct in the right frontal cortex. A 67-year-old man was sudden difficulty using his chopsticks and had weakness in his right thumb and index finger. The brain MRI showed a small infarct in the left precentral cortex.

Superior Rectus-Levator Palpebrae Complex Myositis Presenting as Isolated Painless Ptosis

No abstract available.

Recurrent Cerebral Infarction in Polycythemia Vera

Polycythemia vera (PV) is a chronic myeloproliferative disorder that is characterized by increased production of leukocytes, erythrocytes, and platelets. Arterial and venous thromobotic complications are common in the clinical course of this disorder. There have been a few reports of acute ischemic stroke with PV. A case of PV associated with progression of middle cerebral artery stenosis and recurrent ischemic stroke is presented herein.

Bilateral Striopallidodentate Calcinosis in Chromosome 22q11.2 Deletion Syndrome

Symptomatic bilateral striopallidodentate calcinosis is required to identify the underlying causes. Disorder of calcium metabolism, such as hypoparathyroidism is the most common cause. We report a patient with hypoparathyroidism induced intracranial calcification who presented seizure and psychotic symptoms in adult and finally diagnosed as a choromosome 22q11.2 deletion syndrome.

Magnetic Resonance Findings in Two Episodes of Repeated Cerebral Fat Embolisms in a Patient with Autologous Fat Injection into the Face

We report magnetic resonance image (MRI) and magnetic resonance spectroscopy (MRS) findings in a patient of cerebral fat embolism (CFE) occurred in a 26-year-old woman after an autologous fat injection into the face. After initial neurologic symptom onset, MRI and MRS data were obtained two times to investigate repeated CFE. We obtained the MRS data in the two different time intervals and two different echo times to compare the lesions with normal brain parenchyma. The results of MRS data showed that a decrease in N-acetyl-aspartate, an increase in lactate and a very high early peak of free lipids between 0.9 and 1.4 ppm were obtained at the acute infarcted lesion as compared with normal brain parenchyma. In addition, these findings were more clearly detected on short echo time spectrum rather than long spectrum. A close relationship between the clinical manifestations and MRI and MRS findings of the brain can helpful to distinguish CFE with other conditions and to evaluate the cause materials of infarctions rather than conventional MRI or diffusion-weighted imaging.