Predictors of perfusion computed tomography alterations in stroke mimics attended as stroke code.

BACKGROUND AND PURPOSE: Stroke mimics (SMs) account for a significant number of patients attended as stroke code (SC) with an increasing number over the years. Recent studies show perfusion computed tomography (PCT) alterations in some SMs, especially in seizures. The objective of our study was to evaluate the clinical characteristics and PCT alterations in SMs attended as SC in order to identify potential predictors of PCT alterations in SMs. METHODS: A retrospective study was performed including all SC activations undergoing a multimodal CT study including non-enhanced computed tomography (CT), CT angiography and PCT, as part of our SC protocol, over 39 months. Patients with a final diagnosis of SM after complete diagnosis work-up were therefore selected. Clinical variables, diagnosis, PCT alteration patterns and type of map affected (Tmax or time to peak, cerebral blood flow and cerebral blood volume) were registered. RESULTS: Stroke mimics represent up to 16% (284/1761) of SCs with a complete multimodal study according to our series. Amongst SMs, 26% (74/284) showed PCT alterations. PCT abnormalities are more prevalent in seizures and status epilepticus and the main pattern is alteration of the time to peak map, of unilateral hemispheric distribution or of non-vascular territory. In our series, the independent predictors of alteration in PCT in SMs are aphasia, female sex and older age. CONCLUSIONS: Perfusion computed tomography alterations can be found amongst almost a third of SMs attended as SC, especially older women presenting with aphasia with a final diagnosis of epileptic seizures and status epilepticus.

Acutely altered mental status as the main clinical presentation of multiple strokes in critically ill patients with COVID-19.

BACKGROUND AND AIMS: Cerebral infarction in COVID-19 patients might be associated with a hypercoagulable state related to a systemic inflammatory response. Its diagnosis might be challenging. We present two critically ill patients with COVID-19 who presented acutely altered mental status as the main manifestation of multiple strokes. METHODS: Clinical presentation and diagnostic work-up of the patients. RESULTS: Two patients in their sixties were hospitalized with a bilateral pneumonia COVID-19. They developed respiratory failure and were admitted to ICU for mechanical ventilation and intense medical treatment. They were started on low-molecular-weight heparin since admission. Their laboratory results showed lymphopenia and increased levels of C-reactive protein and D-dimer. Case 1 developed hypofibrinogenemia and presented several cutaneous lesions with biopsy features of thrombotic vasculopathy. Case 2 was performed a CT pulmonary angiogram at ICU showing a bilateral pulmonary embolism. When waking up, both patients were conscious but with a remarkable global altered mental status without focal neurological deficits. A brain MRI revealed multiple acute bilateral ischemic lesions with areas of hemorrhagic transformation in both patients (case 1: affecting the left frontal and temporal lobes and both occipital lobes; case 2: affecting both frontal and left occipital lobes). Cardioembolic source and acquired antiphospholipid syndrome were ruled out. COVID-19-associated coagulopathy was suspected as the possible main etiology of the strokes. CONCLUSION: Acutely altered mental status might be the main manifestation of multiple brain infarctions in critically ill COVID-19 patients. It should be specially considered in those with suspected COVID-19-associated coagulopathy. Full-dose anticoagulation and clinical-radiological monitoring might reduce their neurological consequences.

Management of Large Vessel Occlusion Stroke Related to Infective Endocarditis: Is Mechanical Thrombectomy a Safe Option?

INTRODUCTION: Acute ischemic stroke is the most common neurological complication of infective endocarditis. Intravenous thrombolysis is contraindicated in these patients due to a higher risk of hemorrhagic complications. Whether mechanical thrombectomy has some benefit in these patients remains unanswered although some favorable results can be found in literature. METHODS: We report twelve cases of acute ischemic stroke due to septic emboli treated with mechanical thrombectomy in two comprehensive stroke centers. RESULTS: Median age was 63 years (IQR 58.8-77.5 years). Diagnosis of infective endocarditis was previous to the diagnosis of stroke in three of the patients. There were five cases of prosthetic-valve endocarditis and eight cases of native-valve endocarditis. Two patients were treated with intravenous thrombolysis with an extensive subarachnoid hemorrhage in 24 h follow-up CT in one of them. Another patient suffered an arterial perforation during the endovascular procedure without successful recanalization. 6 of the patients (50%) developed some type of hemorrhagic complications with three cases of symptomatic intracerebral hemorrhage. Early neurological recovery was achieved in 3 (25%) patients. Functional independence at 3 months in patients with successful revascularization was reached in 50% of the cases. CONCLUSIONS: In patients with large vessel acute ischemic stroke related to infective endocarditis, mechanical thrombectomy might be considered with some potential benefit reported. There may be a high risk of hemorrhagic complications, as known for intravenous thrombolysis in this condition, suggesting that this procedure should be carefully evaluated in these patients.

Assessment of Collateral Circulation Using Perfusion CT in Middle Cerebral Artery Thrombectomy-Treated Patients.

INTRODUCTION: The prognostic value of leptomeningeal collateral circulation in thrombectomy-treated patients remains unclear. We evaluated the construct validity of assessing leptomeningeal collateral circulation using a new regional perfusion CT source image-based approach, the Perfusion Acquisition for THrombectomy Scale (PATHS). We also compared the prognostic value of PATHS with a further 6 scales based on various techniques: CT-angiography, perfusion CT, and digital subtraction angiography. Additionally, we studied the relationship between the scores for the different scales. PATIENTS AND METHODS: We performed a retrospective study of consecutive patients with stroke and M1/terminal carotid occlusion treated with thrombectomy in our center. Leptomeningeal collateral circulation was prospectively evaluated using 7 scales: Tan and Miteff (CT Angiography); Calleja, Cao, American Society of Intervention and Therapeutic Neuroradiology/Society of Interventional Radiology, and PATHS (perfusion); and Christoforidis (Digital Subtraction Angiography). Correlations were studied using the Spearman method. RESULTS: The study population comprised 108 patients. All scales predicted the modified Rankin Scale at 3 months (P ≤ .02) and all but 1 (Christoforidis) correlated with 24-hour brain infarct volume (P ≤ .02). These correlations were higher with PATHS (rho = -0.47, P < .001 for 3-month modified Rankin Scale; rho = -0.35, P < .001 for follow-up infarct volume). The multivariate analysis showed PATHS to be an independent predictor of modified Rankin Scale at 3 months less than equal to 2. A crosscorrelation analysis revealed a better correlation between scales that used the same techniques. CONCLUSIONS: PATHS can be used to assess leptomeningeal collateral circulation. PATHS had better prognostic value than other scales; therefore, it might be considered for assessment of leptomeningeal collateral circulation in candidates for thrombectomy. The moderate correlation between scales suggests that scores are not interchangeable.

Clinical, imaging and electroencephalographic characterization of three cases of HaNDL syndrome.

Introduction The syndrome of transient headache and neurological deficits with cerebrospinal fluid lymphocytosis (HaNDL) may mimic stroke when patients present with acute/subacute focal neurological deficits. It would be helpful to identify investigations that assist the neurologist in differentiating between HaNDL and stroke. Case reports We describe three cases that proved to be HaNDL, but were initially considered to be strokes. Hypoperfusion was noted in the CT perfusion (CTP) studies in all three cases, which extended beyond any single cerebral arterial supply. The CTP findings suggested a stroke mimic, and there was no improvement on thrombolysis. MRI failed to show any abnormalities in diffusion and EEGs showed non-epileptiform changes. Lumbar punctures demonstrated a lymphocytic pleocytosis. Conclusion The diagnosis of HaNDL is based on clinical and CSF criteria, but neuroimaging, including CT perfusion, can be helpful in differentiating the clinical syndrome from stroke.

Early automated cerebral edema assessment following endovascular therapy: impact on stroke outcome.

BACKGROUND: Cerebral edema (CED) is associated with poorer outcome in patients with acute ischemic stroke (AIS). The aim of the study was to investigate the factors contributing to greater early CED formation in patients with AIS who underwent endovascular therapy (EVT) and its association with functional outcome. METHODS: We conducted a multicenter cohort study of patients with an anterior circulation AIS undergoing EVT. The volume of cerebrospinal fluid (CSF) was extracted from baseline and 24-hour follow-up CT using an automated algorithm. The severity of CED was quantified by the percentage reduction in CSF volume between CT scans (∆CSF). The primary endpoint was a shift towards an unfavorable outcome, assessed by modified Rankin Scale (mRS) score at 3 months. Multivariable ordinal logistic regression analyses were performed. The ∆CSF threshold that predicted unfavorable outcome was selected using receiver operating characteristic curve analysis. RESULTS: We analyzed 201 patients (mean age 72.7 years, 47.8% women) in whom CED was assessable for 85.6%. Higher systolic blood pressure during EVT and failure to achieve modified Thrombolysis In Cerebral Infarction (mTICI) 3 were found to be independent predictors of greater CED. ∆CSF was independently associated with the probability of a one-point worsening in the mRS score (common odds ratio (cOR) 1.05, 95% CI 1.03 to 1.08) after adjusting for age, baseline mRS, National Institutes of Health Stroke Scale (NIHSS), and number of passes. Displacement of more than 25% of CSF was associated with an unfavorable outcome (OR 6.09, 95% CI 3.01 to 12.33) and mortality (OR 6.72, 95% CI 2.94 to 15.32). CONCLUSIONS: Early CED formation in patients undergoing EVT was affected by higher blood pressure and incomplete reperfusion. The extent of early CED, measured by automated ∆CSF, was associated with worse outcomes.

Predictive value of ischemia location on multimodal CT in thrombectomy-treated patients.

OBJECTIVE: Alberta Stroke Program Early CT Score (ASPECTS) applied to CT-perfusion (CTP) and CT-angiography-source-images (CTA-SI) may improve outcome prediction in large vessel occlusion (LVO) stroke if compared to non-contrast CT (NCCT) alone. Besides, ischemia location may have enhanced capabilities, compared to ischemia volume alone, in predicting stroke outcomes. We aim to evaluate the association between ischemia location as measured by ASPECTS regions in NCCT, CTP maps and CTA-SI and 3 months outcome in patients with LVO treated with mechanical thrombectomy (MT). MATERIAL AND METHODS: Consecutive patients with anterior circulation stroke treated with MT were recorded in a prospectively maintained database at a single center. Modified Rankin scale (mRS) at 3 months >2 was considered a poor outcome. Association of patients' characteristics, NCCT, CTP, and CTA-SI parameters with outcome was evaluated using single-variable analysis and binary logistic regression multivariate analysis for each imaging technique. RESULTS: 177 patients were included. 115 (65%) patients reached a favorable outcome. The involvement of lenticular, caudate, M1, or M2 in all imaging techniques, insula in NCCT and CTA-SI and M5 in CBV maps and CTA-SI was related to functional outcome in bivariate analysis. However, in the multivariate analysis, none ischemia location was independently related to outcome, no matter the imaging technique studied. This finding remained unchanged when restricted to patients with good recanalization and when analyzing subpopulations according to hemisphere involvement or territories association. CONCLUSIONS: Our study suggests ischemia location shouldn't be used solely for decision-making in LVO stroke patients. Its predictive value may be taken in consideration together with other clinical and radiological variables.

Mechanical thrombectomy in orally anticoagulated patients with acute ischemic stroke.

BACKGROUND AND PURPOSE: To investigate the efficacy and safety of mechanical thrombectomy in patients with acute ischemic stroke according to the oral anticoagulation medication taken at the time of stroke onset. MATERIALS AND METHODS: A retrospective multicenter study of prospectively collected data based on data from the registry the Madrid Stroke Network was performed. We included consecutive patients with acute ischemic stroke treated with mechanical thrombectomy and compared the frequency of intracranial hemorrhage and the modified Rankin Scale (mRS) score at 3 months according to anticoagulation status. RESULTS: The study population comprised 502 patients, of whom 389 (77.5%) were not anticoagulated, 104 (20.7%) were taking vitamin K antagonists, and 9 (1.8%) were taking direct oral anticoagulants. Intravenous thrombolysis had been performed in 59.8% and 15.0% of non-anticoagulated and anticoagulated patients, respectively. Rates of intracranial hemorrhage after treatment were similar between non-anticoagulated and anticoagulated patients, as were rates of recanalization. After 3 months of follow-up, the mRS score was ≤2 in 56.3% and 55.7% of non-anticoagulated and anticoagulated patients, respectively (P=NS). Mortality rates were similar in the two groups (13.1%and12.4%, respectively). Among anticoagulated patients, no differences were found for intracranial bleeding, mRS score, or mortality rates between patients taking vitamin K antagonists and those taking direct oral anticoagulants. CONCLUSIONS: Mechanical thrombectomy is feasible in anticoagulated patients with acute ischemic stroke. The outcomes and safety profile are similar to those of patients with no prior anticoagulation therapy.