Infratentorial Stroke Research Articles

Differences in motor network dynamics during recovery between supra- and infra-tentorial ischemic strokes.

Most previous stroke studies have been performed in heterogeneous patient populations. Moreover, the brain network might demonstrate different recovery dynamics according to lesion location. In this study, we investigated variation in motor network alterations according to lesion location. Forty patients with subcortical ischemic stroke were enrolled. Patients were divided into two groups: 21 patients with supratentorial stroke (STS) and 19 patients with infratentorial stroke (ITS). All patients underwent resting-state functional magnetic resonance imaging and behavioral assessment at 2 weeks and 3 months poststroke. Twenty-four healthy subjects participated as a control group. To compare altered connectivity between groups, measures used in previous studies to evaluate interhemispheric balance and global network reorganization were investigated and the relationship between network measures and motor functions were examined. Cortico-cerebellar connectivity was also extracted to investigate its relationship with interhemispheric connectivity. In the STS group, measures related to interhemispheric balance were disrupted compared to the control group 2 weeks poststroke, while this was not found in the ITS group. During recovery, measures related to global network reorganization in the STS group and measures related to interhemispheric balance in the ITS group demonstrated significant changes, respectively. Moreover, motor functions were correlated with altered network measures in both groups. There was an interactive relationship between cortico-cerebellar and interhemispheric cortical connectivity only in the ITS group. Different changes in the motor network were observed depending on the location of stroke lesions. These results might originate from differences in the interactions between cortico-cerebellar and interhemispheric connectivity.

Differences in alteration of motor network between supra- and infratentorial ischemic stroke patients

In recent stroke studies, connectivity-based approaches have been used to investigate recovery-related indicators. However, most of previous studies were performed in heterogenous patients with different lesion locations or different types of stroke. In addition, there is not enough investigation on recovery-related network analysis in the infratentorial stroke (ITS), which may show different network dynamics from the supratentorial stroke (STS). In this study, we investigated the differences in alteration of motor network between STS and ITS in ischemic stroke patients. Forty first-onset ischemic stroke patients were recruited within 2 weeks after stroke onset. Patients were divided into STS and ITS groups according to their lesion location. All patients underwent resting-state fMRI scans twice (2 weeks and 3 months after onset). Twenty-four healthy subjects participated as an age-matched control group. To investigate the altered connectivity during recovery and to compare between groups, various analysis methods such as interhemispheric connectivity, network symmetry, and graph theoretical analysis which were already established in the previous studies were used. In STS group, interhemispheric connectivity was significantly decreased and network symmetry was disrupted compared to control group at 2 weeks post-stroke, while the ITS group did not show differences compared to control group at this time point. During recovery, global efficiency and global reorganization including increasing network efficiency and randomization showed only in the STS group. In contrast, the ITS group demonstrated significantly increased interhemispheric connectivity during recovery. There was an interactive relationship between cortico-cerebellar connectivity and interhemispheric connectivity in the ITS group. Alterations of recovery-related motor network connectivity in ITS patients were very different from that of STS patients. These results may be caused by differences of damage of diverse motor-related pathways by stroke lesion.

An investigation of oral stereognostic ability in patients with stroke : A cross-sectional study

목적: 본 연구는 뇌졸중 환자의 일반적 특성에 따른 구강 입체인지지각 능력의 차이를 알아보고 구강 입체인지지각 능력과 인지기능 사이에 상관관계를 조사하였다. 방법: 본 연구에 84명의 뇌졸중 환자가 참여하였다. 구강 입체인지지각 검사(Oral Stereognostic Test; OST)는 입 안에 각기 다른 도형 20개를 넣고 구분하였다. 구강 입체인지지각 검사는 구강 입체인지지각 총점과 검사 동안 응답에 대한 반응속도(Respone Time; RT)를 확인하였다. 간이 정신상태 검사(Mini-Mental State Examination; MMSE)로 인지기능을 확인하였다. 모든 측정은 임상경력 3년 이상의 작업치료사가 수행하였다. 결과: 실험 후, 흡인과 같은 부작용은 발생하지 않았다. 뇌졸중 환자의 성별, 마비측, 뇌졸중 유형에 따른 구강 입체인지지각 총점, 반응시간, 인지기능의 차이는 보이지 않았다. 손상위치에 따른 인지기능은 유의한 차이가 있었다. 천막상 뇌졸중 환자는 천막하 뇌졸중 환자보다 인지기능에서 유의하게 더 낮은 점수를 나타냈다. 구강 입체인지지각 총점과 인지기능은 유의한 상관관계를 보였다. 결론: 본 연구의 결과는 구강 입체인지지각과 인지기능이 상관이 있으므로 임상에서 이를 고려한 훈련을 실시해야 함을 의미한다. 또한 뇌졸중 환자의 구강 입체인지지각에 대한 기초자료로 유용하게 쓰일 수 있을 것이다.This study was to investigate the differences in oral stereognosis according to general characteristics of stroke patients and the correlation relationship between oral stereognosis and cognitive function. Eighty four stroke patients have participated in this study. The Oral Stereognostic Test (OST) was to tell between 20 different pieces placed in the mouth. OST test was measured in two ways: One is OST total score and the other is the response time (RT) of the test. MMSE was used to identify the cognitive function. Occupational therapists who had over three years of clinical career conducted all measurements. After the experiment, there was no adverse event such as aspiration. No difference was found in OST, RT, and MMSE by sex, hemiplegia side, and stroke type in stroke patients (p>.05). There was a significant difference in MMSE according to the lesion site; the patients with supratentorial strokes showed significantly lower scores on MMSE than those with infratentorial strokes (p<.05). OST and MMSE showed a significant correlation (p<.05). These results demonstrate that one should consider this when conducting clinical training because oral stereognosis and cognitive function are each correlated. It may also be useful as a neuroanatomical basis for oral stereognosis in stroke patients.

Clinical Importance of Temporal Bone Features for the Efficacy of Contrast-Enhanced Sonothrombolysis: a Retrospective Analysis of the NOR-SASS Trial.

Contrast-enhanced sonothrombolysis (CEST) seems to be a safe and promising treatment in acute ischemic stroke. It remains unknown if temporal bone features may influence the efficacy of CEST. We investigated the association between different temporal bone features on admission computed tomography (CT) scan and the outcome in acute ischemic stroke patients included in the randomized Norwegian Sonothrombolysis in Acute Stroke Study (NOR-SASS). Patients diagnosed as stroke mimics and those with infratentorial stroke or with incorrect insonation were excluded. We retrospectively assessed temporal bone heterogeneity (presence of diploë), diploë ratio, thickness, and density on admission CT scans. National institute of Health Stroke Scale (NIHSS) at 24h and modified Rankin Scale (mRS) at 3months were correlated with CT findings both in CEST and sham CEST patients. A total of 99 patients were included of which 52 were assigned to CEST and 47 to sham CEST. Approximately 20% patients had a heterogeneous temporal bone in both the CEST and sham CEST group. All temporal bone CT features studied were associated with female sex. In the CEST group, temporal bone heterogeneity (p=0.006) and higher temporal bone diploë ratio (p=0.002) were associated with higher NIHSS at 24h. There was no association between temporal bone features and mRS at 3months. Approximately 20% of acute ischemic stroke patients have heterogeneous temporal bone and may be resistant to standard 2-MHz transcranial Doppler ultrasound treatment. Sonothrombolysis resistance may easily be predicted by admission CT for better selection.

The Relationship Between Lesion Localization and Dysphagia in Acute Stroke.

Factors that can facilitate early identification of individuals at risk of dysphagia such as stroke location are potentially of great benefit. The aim of this study was to examine the role of hemisphere and lesion location in assessing dysphagia pattern and airway invasion as identified through the use of validated, standardized interpretation measures for the videofluoroscopic swallowing study. Consecutive patients (N=80) presenting with stroke symptoms who had a first-time acute ischemic stroke confirmed on diffusion-weighted magnetic resonance imaging (DW-MRI) scan participated. Three swallowing outcome variables were assessed using regression models: modified barium swallow impairment profile (MBSImP) oral impairment (OI) and pharyngeal impairment (PI) scores and penetration aspiration scale (PAS) score. Subjects were primarily male and demonstrated mild stroke and mild to moderate dysphagia. There was a significantly higher likelihood of abnormal PAS scores for infratentorial lesions compared to right hemisphere location (Odds ratio: 3.1, SE: 1.8, p=0.046) and for Whites compared to African Americans (Odds ratio: 5.5, SE: 2.6, p=<0.001). However, OI scores were higher (worse) in African Americans compared to Whites (Beta=-1.2; SE: 0.56; p=0.037). PI scores had no significant association with race or lesion location. Using DW-MRI to identify infratentorial stroke can help identify individuals at risk of airway invasion; however, imaging information concerning supratentorial infarct hemisphere and location may not be useful to predict which individuals with mild stroke are at risk for dysphagia and aspiration when admitted with acute stroke symptoms. Future studies should explore the role of race in the development of stroke-related dysphagia.

Attitudes to Stem Cell Therapy Among Ischemic Stroke Survivors in the Lund Stroke Recovery Study.

Preclinical studies suggest that stem cell therapy (SCT) may improve poststroke recovery, and clinical trials investigating safety are ongoing. However, knowledge about patients' attitudes to SCT in stroke is limited. We evaluated the knowledge and attitudes to this therapeutic approach as well as possible factors influencing this among stroke patients potentially suitable for SCT. Consecutive first-ever acute ischemic stroke patients aged 20-75 years with NIH stroke scale scores 1-18 were included. Exclusion criteria were severe comorbidities or infratentorial stroke. Clinical follow-up after 3-5 years assessed severity of residual stroke symptoms, cognitive function, functional status, patient-reported outcome, and comorbidity, and after receiving standardized information, the participants also completed an eight-item questionnaire on knowledge and attitudes about SCT. The relationships between clinical variables and positive attitude to SCT were assessed with logistic regression analyses. Of 108 patients included at baseline, 84 participated at follow-up and completed the questionnaire. In total, 12% had prior knowledge of SCT. When informed, 63% were positive toward it and 36% reported willingness to participate in SCT trials. Only 5%-8% expressed ethical considerations regarding different stem cell sources. Positive attitudes to SCT were associated with male gender (OR: 3.74; 95% CI: 1.45-9.61; P < 0.01) and better patient-reported outcome (OR: 1.02; 95% CI: 1.00-1.04; P < 0.05). In conclusion, stroke patients had limited prior knowledge of SCT, yet attitudes were positive among the majority after receiving standardized and neutral information. Gender and degree of stroke recovery may influence attitudes to SCT, indicating a need for targeted information to improve knowledge about SCT.

Abstract WP175: Attitudes to Stem Cell-based Treatments Among Ischemic Stroke Patients

Background: Pre-clinical studies have shown that stem cell therapy (SCT) may improve recovery after stroke, and clinical trials investigating safety are ongoing. It is important to consider stroke patients’ knowledge and attitudes about SCT, as these factors may have implications for the possible clinical use of SCT. Therefore, we examined the knowledge and attitudes about SCT among stroke patients potentially suitable for such therapy. Methods: We recruited consecutive first-ever ischemic stroke patients admitted to Skåne University Hospital in Lund, Sweden, in 2009-2011. Included patients were aged 20-75 years, had a National Institutes of Health Stroke Scale (NIHSS) score of 1-18, and underwent DW-MRI within 4 days of stroke onset. Patients with severe comorbidity, contraindications to MRI, and/or infratentorial stroke were excluded. A clinical follow-up was performed after 3-5 years assessing stroke severity (NIHSS), stroke recovery (NIHSS baseline - NIHSS follow-up ; ΔNIHSS), functional status (modified Rankin Scale; mRS), comorbidity (Charlson Comorbidity Index; CCI), and patient-reported outcome (Stroke Impact Scale; SIS). The participants also completed an 8-part questionnaire on knowledge and attitudes about SCT. Results: Of 108 patients at baseline, 84 participated in the follow-up. In total, 12% had prior knowledge of SCT. Also, 63% had positive attitudes towards it. Positive attitudes towards SCT were associated with male sex (crude OR: 3.7; 95% CI: 1.5-9.6; P =0.006) and better patient-reported outcome (crude OR: 1.0; 95% CI: 1.0-1.0; P =0.034). No such associations were found for age, education, functional status and stroke severity at follow-up. Likewise, willingness to participate in clinical SCT trials was associated with male sex (crude OR: 5.4; 95% CI: 1.8-16.2; P =0.003) and a higher degree of stroke recovery (crude OR: 1.3; 95% CI: 1.1-1.7; P =0.005). Conclusions: Our findings may have implications for SCT trials in stroke as most stroke patients had limited knowledge about SCT, indicating a need for patient education programs. The attitudes towards SCT were mostly positive and willingness to participate in SCT trials was associated with male sex and higher degree of stroke recovery, which may affect patient selection.

Prolonged impairment of deglutition in supratentorial ischaemic stroke: the predictive value of Parramatta Hospitals' Assessment of Dysphagia.

Up to 50% of ischaemic stroke patients show initial dysphagia, which may persist for months. Guidelines recommend switching nasogastric (NG) to percutaneous endoscopic gastrostomy (PEG) tube feeding at the second week after the stroke if impaired deglutition is expected for another 4 weeks. Precise prognostic criteria are lacking. We hypothesised that the Parramatta Hospitals' Assessment of Dysphagia (PAHD) performed 8 to 10 days after the stroke predicts impaired deglutition for another 4 weeks. After a first dysphagia assessment (buccolingual motor function, liquid and semisolid swallow tests, "two-out-of-six" scale) within 48 hours of onset, patients with a first hemispheric stroke and risk of aspiration, defined as a two-out-of-six scale score of ≥2 (dysphonia, dysarthria, abnormal gag reflex, abnormal volitional cough, cough / voice change after swallowing) were included and were assessed by a blinded rater using the PHAD. The same dysphagia assessments were repeated 8 to 10 days after the stroke (second assessment) and patients remained in the study if the two-out-of-six scale score remained ≥2. At a final evaluation by telephone after 4 weeks, impaired deglutition was assessed with the Bogenhausen dysphagia score (BODS-2). Exclusion criteria were infratentorial or recurrent stroke and pre-existing dysphagia. The primary objective was to define a threshold score and value of the PHAD at second assessment that predicted impaired deglutition as assessed with the BODS-2 (score ≥4) at the final evaluation. The secondary objective was to explore the value of the PHAD assessed within 48 hours to predict impaired deglutition (BODS-2 ≥4) at final evaluation. To evaluate the predictive value of the PHAD score assessed 8 to 10 days after stroke onset for impaired deglutition for another 4 weeks, we determined the area under the receiver operating curve (ROC AUC). Over a 1-year period, 29 out of 252 assessed patients remained at risk of aspiration after the second assessment. In these patients, ROC analysis of PHAD recorded 8 to 10 days after the stroke showed excellent accuracy with an AUC of 0.971 (cut-off 71.5) predicting a BODS-2 score of ≥4 at final evaluation. The accuracy of ROC analysis of the PHAD score assessed within 48 hours of stroke onset to predict prolonged impairment of deglutition was poor (AUC 0.685). In a selected population at risk of aspiration, the PHAD with a threshold of 70 assessed in the second week after stroke onset may be a valuable tool to predict prolonged impairment of deglutition for another 4 weeks and to guide the decision about switching from NG to PEG tube feeding after supratentorial ischaemic stroke.

Diagnostic accuracy of whole-brain CT perfusion in the detection of acute infratentorial infarctions.

Although the diagnostic performance of whole-brain computed tomographic perfusion (WB-CTP) in the detection of supratentorial infarctions is well established, its value in the detection of infratentorial strokes remains less well defined. We examined its diagnostic accuracy in the detection of infratentorial infarctions and compared it to nonenhanced computed tomography (NECT), aiming to identify factors influencing its detection rate. Out of a cohort of 1380 patients who underwent WB-CTP due to suspected stroke, we retrospectively included all patients with MRI-confirmed infratentorial strokes and compared it to control patients without infratentorial strokes. Two blinded readers evaluated NECT and four different CTP maps independently for the presence and location of infratentorial ischemic perfusion deficits. The study was designed as a retrospective case-control study and included 280 patients (cases/controls=1/3). WB-CTP revealed a greater diagnostic sensitivity than NECT (41.4 vs. 17.1%, P=0.003). The specificity, however, was comparable (93.3 vs. 95.0%). Mean transit time (MTT) and time to drain (TTD) were the most sensitive (41.4 and 40.0%) and cerebral blood volume (CBV) the most specific (99.5%) perfusion maps. Infarctions detected using WB-CTP were significantly larger than those not detected (15.0 vs. 2.2ml; P=0.0007); infarct location, however, did not influence the detection rate. The detection of infratentorial infarctions can be improved by assessing WB-CTP as part of the multimodal stroke workup. However, it remains a diagnostic challenge, especially small volume infarctions in the brainstem are likely to be missed.

Sensitivity of Diffusion-Weighted STEAM MRI and EPI-DWI to Infratentorial Ischemic Stroke.

ObjectivesTo assess the sensitivity of stimulated echo acquisition mode diffusion weighted imaging (STEAM-DWI) to ischemic stroke in comparison to echo-planar imaging diffusion weighted imaging (EPI-DWI) in the infratentorial compartment.MethodsFifty-seven patients presenting with clinical features of infratentorial stroke underwent STEAM-DWI, high-resolution EPI-DWI (HR-DWI, 2.5 mm slice thickness) and low-resolution EPI-DWI (LR-DWI, 5 mm slice thickness). Four readers assessed the presence of ischemic lesions and artifacts. Agreement between sequences and interobserver agreement on the presence of ischemia were calculated. The sensitivities of the DWI sequences were calculated in 45 patients with a confirmed diagnosis of infratentorial stroke.ResultsMedian time from symptom onset to imaging was 24 hours. STEAM-DWI agreed with LR-DWI in 89.5% of cases (kappa = 0.72, p<0.0001) and with HR-DWI in 89.5% of cases (kappa = 0.68, p<0.0001). STEAM-DWI showed fewer intraparenchymal artifacts (1/57) than HR-DWI (44/57) and LR-DWI (41/57). Ischemia was visible in 87% of cases for LR-DWI, 93% of cases for HR-DWI, and 89% of cases for STEAM-DWI. Interobserver agreement was good for STEAM-DWI (kappa = 0.62, p<0.0001).ConclusionsCompared to the best currently available MR sequence for detecting ischemia (HR-DWI), STEAM-DWI shows fewer artifacts and a similar sensitivity to infratentorial stroke.

Early Initiation of Anticoagulation with Direct Oral Anticoagulants in Patients after Transient Ischemic Attack or Ischemic Stroke

Direct oral anticoagulants (DOACs) are increasingly used for secondary prevention of cardioembolic stroke. While DOACs are associated with a long-term reduced risk of intracranial hemorrhage compared to vitamin K antagonists, pivotal trials avoided the very early period after stroke and few data exist on early initiation of DOAC therapy post stroke. We retrospectively analyzed data from our prospective database of all consecutive transient ischemic attack (TIA) or ischemic stroke patients with atrial fibrillation treated with DOACs during hospital stay. As per our institutional treatment algorithm for patients with cardioembolic ischemia DOACs are started immediately in TIA and minor stroke (group 1), within days 3-5 in patients with infarcts affecting one third or less of the middle cerebral artery, the anterior cerebral artery, or the posterior cerebral artery territories (group 2) as well as in infratentorial stroke (group 3) and after 1-2 weeks in patients with large infarcts (>⅓MCA territory, group 4). We investigated baseline characteristics, time to initiation of DOAC therapy after symptom onset, and hemorrhagic complications. In 243 included patients, administration of DOAC was initiated 40.5 hours (interquartile range [IQR] 23.0-65.5) after stroke onset in group 1 (n = 41) and after 76.7 hours (IQR 48.0-134.0), 108.4 hours (IQR 67.3-176.4), and 161.8 hours (IQR 153.9-593.8) in groups 2-4 (n = 170, 28, and 4), respectively. Two cases of asymptomatic intracranial hemorrhage (.8%) and 1 case of symptomatic intracranial hemorrhage (.4%) were observed, both in group 2. No severe safety issues were observed in early initiation of DOACs for secondary prevention after acute stroke in our in-patient cohort.

Exploration of factors affecting prognosis of stroke preceded by transient ischemic attack

Background: Age is the most important risk factor for stroke. The regional brain affection was not considered in a comparison between different brain locations as a predictor for outcome in those with and without prior TIA.Aims and Objectives: Can transient Ischemic attack predict stroke prognosis?Materials and Methods: Fifty nine patients, aged ≥ 55 years old, with recent ischemic stroke were studied, with (cases, 40.68%) and without (controls) antecedent TIA. National Institutes of Health Stroke Scale (NIHSS), modified Rankin scale (MRS), and California risk score (CRS) were assessed. A brain computed tomography was done.Results: Older age was a predictor of more severe stroke (P&lt;0.001). Different latencies for TIA were studied. With reference to our controls, better prognosis was found only in cases with TIA ≤ seven days as a predictor for better NIHSS and MRS. In cases, CRS was a significant predictor of shorter latency. Infratentorial ischemic stroke, not supratentorial ischemic stroke, with prior TIA, was a significant predictor of lower NIHSS.Conclusion: TIA ≤ seven days is a predictor for better NIHSS and MRS.Asian Journal of Medical Sciences Vol.7(4) 2016 68-74

Thin section magnetic resonance diffusion-weighted imaging in the detection of acute infratentorial stroke.

Magnetic resonance diffusion-weighted imaging (DWI) is the most accurate technique available for demonstrating acute infarction; however, false-negative DWI is higher in the infratentorium due to the limited spatial resolution with conventional 5mm DWI. The aim of this study was to compare 5mm DWI with 3mm DWI in the detection of acute infratentorial infarction. A 3mm DWI sequence of the infratentorium was incorporated into the conventional MRI stroke protocol for the evaluation of patients with vertebrobasilar stroke-like deficits. The 5mm and 3mm DWI sequences were assessed by two neuroradiologists who were blinded to the clinical findings. Sensitivity and specificity analysis was then performed against the final clinical diagnosis. The sensitivity for detection of infratentorial infarction was 81.1% for 5mm DWI and 94.6% for 3mm DWI and the specificity was 100% for 5mm DWI and 97.7% for 3-mm DWI. The false-negative rate in detection of infratentorial infarcts was 5.6% for the 5-mm sequence and 1.6% for the 3-mm sequence. The six 5-mm DWI false-negative cases (4.8%) were less than 9mm in diameter (3-8mm, average 4.67mm) and located in the brainstem. This supports the hypothesis that small lesions may not be detected on 5mm DWI due to partial volume averaging. Where there is clinical suspicion of infratentorial infarction, 3mm DWI of the infratentorium adds sensitivity compared to 5mm DWI with only a small reduction in specificity.

Thrombosis at the Site of Pulmonary Venous Anastomosis Following Lung Transplantation Presenting with Multiple, Bilateral, Supra- and Infra-Tentorial Ischemic Strokes in the Setting of a Known Patent Foramen Ovale (P4.355)

Thrombosis at the Site of Pulmonary Venous Anastomosis Following Lung Transplantation Presenting with Multiple, Bilateral, Supra- and Infra-Tentorial Ischemic Strokes in the Setting of a Known Patent Foramen Ovale (P4.355)

Infratentorial posterior circulation stroke in a Nigerian population: Clinical characteristics, risk factors, and predictors of outcome.

Background:Posterior circulation stroke (PCS), though less common, differs from stroke in anterior circulation in many aspects. Relatively, it portends a poorer prognosis. However, there is a paucity of data from African countries, in particular, where stroke is a menace.Objective:The study aimed to evaluate the etiology, clinical characteristics, outcome, and predictors of outcome in a cohort of patients with IPCS in Northwestern Nigeria.Materials and Methods:Out of 595 patients with stroke, we prospectively analyzed 57 patients with PCS in a Tertiary Care Center in Kano, Northwestern Nigeria. Patients were analyzed for demographic data, risk factors, clinical characteristics, stroke subtypes, mortality, and predictors of mortality.Results:Posterior circulation ischemic stroke accounted for 57 (9.6%) of 595 of all strokes seen in the study period. They comprised 44 males (mean age 47.8 ± 17.7) and 13 females (mean age 46.3 ± 13.7). Overall, their age ranged between 24 and 90 (mean age 47.4 ± 16.7). However, 52.7% of the patients were < 45 years of age. The most common site affected was the cerebellum seen in 33 (57.9%) patients. Hypertension was the most common risk factor (86%). Headache and vertigo were the most common features accounting for 83.6% and 86.3%, respectively. Thirty-eight (66.7%) patients had an ischemic stroke. Twenty-one (36.8%) of the patients died during the 1-month period of follow-up. Independent predictors of death in the study were hyperglycemia on admission and hemorrhagic stroke.Conclusions:IPCS occurred in a relatively younger age group. Headache and vertigo were the most common symptoms. The independent predictors of death in the study were hyperglycemia at presentation and hemorrhagic stroke.

Model of understanding fatigue after stroke.

Fatigue is ubiquitous but it is more common and more severe in patients with acute and chronic conditions, including stroke. The reported proportion of people with fatigue after stroke ranges from 23% to 75%.1 The variation in proportion between studies reflects the heterogeneity in the studied populations, time since stroke, and assessment methods for fatigue. Fatigue is common immediately after stroke, and it tends to persist in most but not all patients. It contributes to lower quality of life and a higher risk of death.2,3 How to manage and prevent fatigue is ranked by stroke survivors and health professionals among the top 10 research priorities relating to life after stroke.4 However, there is no effective treatment, which is partly because of our lack of knowledge of its mechanisms. Fatigue after stroke may share some common underlying mechanisms with other conditions. For example, Zedlitz and colleagues found that the psychosocial profiles of stroke patients with fatigue were similar to those reported in patients with cancer, multiple sclerosis, and chronic fatigue syndrome.5 Several fatigue models have been developed for patients with other conditions; a myriad of biological,6,7 psychosocial,8,9 and behavioral factors,9 as well as other symptoms, such as pain and sleep problems,10 are involved. In this review, we explored whether these factors contribute to fatigue after stroke. We systematically reviewed studies of post-stroke fatigue (PSF) and discussed the definition of PSF, its natural history, and its associations. By drawing on literature of fatigue in other conditions alongside evidence from stroke studies, we propose a conceptual model of PSF. This model is potentially useful in understanding the mechanisms of PSF and informing the development of its treatment. In stroke studies, PSF is usually defined by cut-off scores on fatigue …

Abstract T P150: NIHSS Zero Strokes: Immeasurable but Not Innocent

Aims: Patients with acute ischemic stroke (AIS) lasting &gt;24 hours may have an immeasurable deficit on the admission NIHSS score. We sought to better characterize factors that are associated with NIHSS zero strokes and evaluate their long term outcome. Methods: We used all AIS patients with a measurable admission NIHSS in the Acute STroke Registry and Analysis and of Lausanne (ASTRAL) from 2003 - 2012. We then retrospectively analyzed and compared patients with an admission NIHSS of zero with all other patients regarding demographics, clinical characteristics, radiological and laboratory findings in uni- and multivariate analyses. Patients with a pre-stroke NIHSS&gt;0 were also considered “NIHSS zero strokes” if a clearly described preexisting deficit accounted for the current deficit and no new NIHSS points were found. Outcome was assessed at 3 months using the modified Rankins score corrected for pre-stroke disability (corrected mRS) and considered favorable if it was ≤ 1. Combined stroke &amp; TIA recurrences and rehospitalisation rates over 12 months were compared. Results: Comparing 109 NIHSS zero with 2’189 other strokes in multivariate analysis, patients with NIHSS zero stroke had lower pre-stroke disability levels, longer onset-to-hospital delays, and more lacunar and infratentorial strokes. When comparing radiological and laboratory finding in the two groups, NIHSS zero patients were less likely to have acute ischemic changes on acute NCCT, less arterial pathology on acute cervical and intracranial imaging and lower creatinine levels. In unadjusted analysis, NIHSS zero patients were more likely to have favorable corrected mRS (zero vs. others: 83.2% vs. 44.6%) and less likely to die (3.9% vs. 13.3%) at 12 months. Recurrence rates were similar (9.2% vs. 12.9%). Conclusion: Patients with NIHSS zero strokes as compared with all other patients have more frequently lacunar and infrantentorial strokes, normal acute CT, and less arterial pathology. However a significant minority faces persisting handicap at 12 months and recurrent ischemic events. These findings suggest that NIHSS zero stroke patients have better outcomes but still require support and aggressive secondary prevention.

Difficulty of MRI based identification of lesion age by acute infra-tentorial ischemic stroke.

BackgroundSystemic thrombolysis in acute ischemic stroke is restricted to the 4.5 h time window. Many patients are excluded from this treatment because symptom onset is unknown. Magnetic resonance imaging (MRI) studies have shown that stroke patients presenting with acute supra-tentorial diffusion-weighted imaging (DWI) lesions that do not have matching lesions on fluid attenuated inversion recovery (FLAIR) are likely to be within a 4.5 hour time window. This study examines the DWI-FLAIR mismatch in infra-tentorial stroke.MethodsThis was a retrospectively conducted substudy of the “1000+” study; a prospective, single-center observational study (http://clinicaltrials.gov; NCT00715533). Fifty-six patients with infra-tentorial stroke confirmed by MRI and known symptom onset who underwent the scan within 24 h after symptom onset were analysed. Two neurologists blinded to clinical information separately rated the DWI lesion visibility on FLAIR. Lesion volume, relative signal intensities of DWI and relative apparent diffusion coefficient values were determined.ResultsRegarding baseline characteristics our study population had a median age of 66 years, a median time from symptom onset to MRI of 616.5 minutes, a median NIHSS of 3 and a median DWI lesion volume of 0.26 ml. A negative FLAIR allocated patients to a time window under 4.5 h correctly with a sensitivity of 55% and a specificity of 61%, a positive predictive value of 44% and a negative predictive value of 71%. FLAIR positivity decreased with age (p = 0.018), and showed no significant correlation to lesion volume (p = 0.145).ConclusionsIn our study the DWI-FLAIR-Mismatch does not help to reliably identify patients within 4.5 h of symptom onset in acute ischemic infra-tentorial stroke. Thus therapeutical decisions based on the DWI-FLAIR mismatch estimation of time from onset cannot be recommended in patients with infra-tentorial stroke.

Longitudinal Polysomnographic Assessment from Acute to Subacute Phase in Infratentorial versus Supratentorial Stroke

Background: Regulation of sleep and sleep-related breathing resides in different brain structures. Vascular lesions can be expected to differ in their consequences on sleep depending on stroke topography. However, studies addressing the differences in sleep and sleep-related breathing depending on stroke topography are scarce. The aim of the present investigation was to compare the sleep and sleep-related breathing of patients with supratentorial versus infratentorial stroke. Methods: This study was part of the prospective multicenter study SAS-CARE-1 (Sleep-Disordered Breathing in Transient Ischemic Attack (TIA)/Ischemic Stroke and Continuous Positive Airway Pressure (CPAP) Treatment Efficacy (SAS-CARE); NCT01097967). We prospectively included 14 patients (13 male, age 66 ± 6 years) with infratentorial lesions and 14 patients (14 male, age 64 ± 7 years) with supratentorial lesions, matched for age and stroke severity. Polysomnography was recorded in all during the acute phase within 9 days after stroke onset and 3 months later. Results: During the acute phase after stroke, patients with infratentorial lesions had significantly more sleep-related breathing disorders than patients with supratentorial lesions with an apnea-hypopnea index >20 observed in 8 (57%) patients with infratentorial stroke and in only 2 (14%) patients with supratentorial stroke. Sleep-related breathing improved from the acute to the subacute phase (3 months), albeit remaining elevated in a significant proportion of subjects. Sleep parameters did not differ between the two patient groups but there was a general improvement of sleep from the acute to the subacute phase which was comparable for both patient groups. Although stroke severity was mild, recovery after 3 months was worse in patients with infratentorial stroke with 12 of 14 patients with supratentorial stroke being symptom free (NIHSS = 0), while this was the case for only 6 of 14 patients with infratentorial stroke. Conclusions: Patients with infratentorial lesions are at an increased risk for sleep-related breathing disorders, which are frequent in this group. Monitoring of sleep-related breathing is therefore especially recommended in patients with infratentorial stroke. Because of the absence of reliable differences in sleep parameters between the two patient groups, polygraphy, with reduced diagnostic costs, rather than polysomnography could be considered. The higher prevalence of sleep-related breathing disorders and the poorer recovery of patients with infratentorial lesions suggest that early treatment interventions should be considered.

White Matter Hyperintensities and Cognitive Dysfunction in Patients With Infratentorial Stroke

ObjectiveTo determine whether cognitive function is associated with white matter hyperintensities (WMH) in patients with infratentorial stroke.MethodsThis was a retrospective, cross-sectional study. Twenty-four first-ever infratentorial stroke patients between 18 and 60 years of age were enrolled. WMH was evaluated by the Fazekas scale and the Scheltens scale. Cognitive functions were assessed using the Korean Mini-Mental Status Examination (K-MMSE), Rey-Osterrieth Complex Figure Test, and the Seoul Computerized Neuropsychological Test Battery (SCNT) at one month after stroke. All participants were divided into two groups based on the presence of WMH (no-WMH group and WMH group). General characteristics and cognitive functions were compared between the groups.ResultsThere were no significant differences in general characteristics, such as age, stroke type, hypertension history, and education level between the two groups. However, K-MMSE in the WMH group was significantly lower compared to the no-WMH group (p<0.05). The verbal learning test score in SCNT was significantly higher in the no-WMH group compared to the WMH group (p<0.05). Executive function in the no-WMH group tended to be higher compared to the WMH group.ConclusionImpairment of cognitive function in patients with infratentorial stroke appeared to be associated with WMH. WMH should be carefully evaluated during rehabilitation of infratentorial stroke patients.