MR microscopy to assess clot composition following mechanical thrombectomy predicts recanalization and clinical outcome.

BACKGROUND: Mechanical thrombectomy (MT) is the standard of care for patients with a stroke and large vessel occlusion. Clot composition is not routinely assessed in clinical practice as no specific diagnostic value is attributed to it, and MT is performed in a standardized 'non-personalized' approach. Whether different clot compositions are associated with intrinsic likelihoods of recanalization success or treatment outcome is unknown. METHODS: We performed a prospective, non-randomized, single-center study and analyzed the clot composition in 60 consecutive patients with ischemic stroke undergoing MT. Clots were assessed by ex vivo multiparametric MRI at 9.4 T (MR microscopy), cone beam CT, and histopathology. Clot imaging was correlated with preinterventional CT and clinical data. RESULTS: MR microscopy showed red blood cell (RBC)-rich (21.7%), platelet-rich (white,38.3%) or mixed clots (40.0%) as distinct morphological entities, and MR microscopy had high accuracy of 95.4% to differentiate clots. Clot composition could be further stratified on preinterventional non-contrast head CT by quantification of the hyperdense artery sign. During MT, white clots required more passes to achieve final recanalization and were not amenable to contact aspiration compared with mixed and RBC-rich clots (maneuvers: 4.7 vs 3.1 and 1.2 passes, P<0.05 and P<0.001, respectively), whereas RBC-rich clots showed higher probability of first pass recanalization (76.9%) compared with white clots (17.4%). White clots were associated with poorer clinical outcome at discharge and 90 days after MT. CONCLUSION: Our study introduces MR microscopy to show that the hyperdense artery sign or MR relaxometry could guide interventional strategy. This could enable a personalized treatment approach to improve outcome of patients undergoing MT.

IV Thrombolysis With or Without Endovascular Treatment for Suspected Ischemic Stroke in Patients With Intracranial Tumors.

BACKGROUND AND OBJECTIVES: IV thrombolysis (IVT) for suspected ischemic stroke in patients with intracranial neoplasms is off-label. However, data on risks of intracranial hemorrhage (ICH) are scarce. METHODS: In a multicenter registry-based analysis within the European Thrombolysis in Ischemic Stroke Patients (TRISP) collaboration, we assessed frequencies of symptomatic and fatal ICH after IVT for suspected ischemic stroke in patients with intracranial tumors by descriptive statistics and analyzed associations with clinical and imaging characteristics by binary logistic regression. Definition of symptomatic ICH was based on the clinical criteria of the European Cooperative Acute Stroke-II trial including hemorrhage at any site in cranial imaging and concurrent clinical deterioration. RESULTS: Screening data of 21,289 patients from 14 centers, we identified 105 patients receiving IVT; among them were 29 patients (28%) with additional endovascular treatment, with suspected, that is, imaging-based, or histologically confirmed diagnosis of intracranial tumors. Among 104 patients with CT or MRI after IVT available, symptomatic and fatal ICH were observed in 9 and 4 patients (9% and 4%, respectively). Among 82 patients with suspected or confirmed meningioma, symptomatic and fatal ICH occurred in 6 and 3 patients (7% and 4%), respectively. In 18 patients with intra-axial suspected or confirmed primary or secondary brain tumors, there was 1 symptomatic nonfatal ICH (6%). Of 4 patients with tumors of the pituitary region, 2 patients (50%) had symptomatic ICH including 1 fatal ICH (25%). Tumor size was not associated with the occurrence of symptomatic ICH (odds ratio 2.8, 95% CI 0.3-24.8, p = 0.34). DISCUSSION: In our dataset from routine clinical care, we provide insights on the safety of IVT for suspected ischemic stroke in patients with intracranial tumors, a population that is commonly withheld thrombolysis in clinical practice and prospective trials. Except for a potential high risk of symptomatic ICH after IVT in patients with tumors of the pituitary region, frequencies of symptomatic ICH in patients with intracranial tumors in our cohort seem to be in the upper range of rates observed in previous studies within the TRISP cooperation. These results may guide individual treatment decisions in patients with acute stroke and intracranial tumors with potential benefit of IVT.

Trimethylamine-N-Oxide Levels Are Similar in Asymptomatic vs. Symptomatic Cerebrovascular Atherosclerosis.

Introduction: Trimethylamine-N-oxide (TMAO) is correlated with atherosclerosis and vascular diseases such as coronary heart disease and ischemic stroke. The aim of the study was to investigate whether TMAO levels are different in symptomatic vs. asymptomatic cerebrovascular atherosclerosis. Methods: This was a prospective, case-control study, conducted at a tertiary care university hospital. Patients were included if they had large-artery atherosclerosis (TOAST criteria). Symptomatic patients with ischemic stroke were compared with asymptomatic patients. As primary endpoint, TMAO levels on admission were compared between symptomatic and asymptomatic patients. Univariable analysis was performed using Mann-Whitney U test and multivariable analysis using binary logistic regression. TMAO values were adjusted for glomerular filtration rate (GFR), age, and smoking. Results: Between 2018 and 2020, 82 symptomatic and asymptomatic patients were recruited. Median age was 70 years; 65% were male. Comparing symptomatic (n = 42) and asymptomatic (n = 40) patients, no significant differences were found in univariable analysis in TMAO [3.96 (IQR 2.30-6.73) vs. 5.36 (3.59-8.68) µmol/L; p = 0.055], GFR [87 (72-97) vs. 82 (71-90) ml/min*1.73 m2; p = 0.189] and age [71 (60-79) vs. 69 (67-75) years; p = 0.756]. In multivariable analysis, TMAO was not a predictor of symptomatic cerebrovascular disease after adjusting for age and GFR [OR 1.003 (95% CI: 0.941-1.070); p = 0.920]. In a sensitivity analysis, we only analyzed patients with symptomatic stenosis and excluded patients with occlusion of brain-supplying arteries. Again, TMAO was not a significant predictor of symptomatic stenosis [OR 1.039 (0.965-1.120), p = 0.311]. Conclusion: TMAO levels could not be used to differentiate between symptomatic and asymptomatic cerebrovascular disease in our study.

Radiation exposure in endovascular stroke treatment of acute basilar artery occlusions-a matched-pair analysis.

PURPOSE: To determine the radiation exposure in endovascular stroke treatment (EST) of acute basilar artery occlusions (BAO) and compare it with radiation exposure of EST for embolic middle cerebral artery occlusions (MCAO). METHODS: In this retrospective analysis of an institutional review board-approved prospective stroke database of a comprehensive stroke center, we focused on radiation exposure (as per dose area product in Gy × cm2, median (IQR)), procedure time, and fluoroscopy time (in minutes, median [IQR]) in patients receiving EST for BAO. Patients who received EST for BAO were matched case by case with patients who received EST for MCAO according to number of thrombectomy attempts, target vessel reperfusion result, and thrombectomy technique. RESULTS: Overall 180 patients (n = 90 in each group) were included in this analysis. General anesthesia was conducted more often during EST of BAO (BAO: 75 (83.3%); MCAO: 18 (31.1%), p < 0.001). Procedure time (BAO: 31 (20-43); MCAO: 27 (18-38); p value 0.226) and fluoroscopy time (BAO: 29 (20-59); MCAO: 29 (17-49), p value 0.317) were comparable. Radiation exposure was significantly higher in patients receiving EST for BAO (BAO: 123.4 (78.7-204.2); MCAO: 94.3 (65.5-163.7), p value 0.046), which represents an increase by 23.7%. CONCLUSION: Endovascular stroke treatment of basilar artery occlusions is associated with a higher radiation exposure compared with treatment of middle cerebral artery occlusions.

Radiation exposure per thrombectomy attempt in modern endovascular stroke treatment in the anterior circulation.

OBJECTIVE: To quantify radiation exposure (RE) of endovascular stroke treatment (EST) in the anterior circulation per thrombectomy attempt and determine causes for interventions associated with high RE. METHODS: A retrospective single-center study of an institutional review board-approved stroke database of patients receiving EST for large vessel occlusions in the anterior circulation between January 2013 and April 2018 to evaluate reference levels (RL) per thrombectomy attempt. ESTs with RE above the RL were analyzed to determine causes for high RE. RESULTS: Overall, n = 544 patients (occlusion location, M1 and M2 segments of the middle cerebral artery 53.5% and 27.2%, carotid artery 17.6%; successful recanalization rate 85.7%) were analyzed. In the overall population, DAP (in Gy cm2, median (IQR)) was 113.7 (68.9-181.7) with a median fluoroscopy time of 31 min (IQR, 17-53) and a median of 2 (IQR, 1-4) thrombectomy attempts. RE increased significantly with every thrombectomy attempt (DAP1, 68.7 (51.2-106.8); DAP2, 106.4 (84.8-115.6); p value1vs2, < 0.001; DAP3, 130.2 (89.1-183.6); p value2vs3, 0.044; DAP4, 169.9 (128.4-224.1); p value3vs4, 0.001; and DAP5, 227.6 (146.3-294.6); p value4vs5, 0.019). Procedures exceeding the 90th percentile of the attempt-dependent radiation exposure level were associated with procedural complications (n = 17/52, 29.8%) or a difficult vascular access (n = 8/52, 14%). CONCLUSIONS: Radiation exposure in endovascular stroke treatment is depending on the number of thrombectomy attempts. Radiation exposure doubles when three attempts and triples when five attempts are necessary compared with single-maneuver interventions. Procedural complications and difficult vascular access were associated with a high radiation exposure in this collective. KEY POINTS: • Radiation exposure of endovascular stroke treatment (EST) is dependent on the number of thrombectomy attempts. • Reference levels as means for quality control in hospitals performing endovascular stroke treatment should be defined by the number of thrombectomy attempts-we suggest 107 Gy cm2, 156 Gy cm2, 184 Gy cm2, 244 Gy cm2, and 295 Gy cm2 for 1 to 5 maneuvers, respectively, for EST of the anterior circulation • Cases with high rates of radiation exposure are associated with periprocedural complications and difficult anatomical access as a probable cause for a high radiation exposure.

Effect of mode of anesthesia on radiation exposure in patients undergoing endovascular recanalization of anterior circulation embolic stroke.

PURPOSE: To determine the effect of general anesthesia (GA) versus conscious sedation (CS) on radiation exposure (RE), procedure time (PT), and fluoroscopy time (FT) in patients receiving endovascular stroke treatment (EST) for large vessel occlusions (LVOs) in the anterior circulation. METHODS: Retrospective analysis of an institutional review board-approved prospective stroke database of a comprehensive stroke center focusing on RE (as dose area product (DAP) in Gy.cm², median (IQR)), PT, and FT (in minutes, median (IQR)) in patients receiving EST for LVOs of the anterior circulation according to the mode of anesthesia during the intervention. RESULTS: Overall 544 patients were included in this analysis (GA: n=143, CS: n=401). For all included LVOs in the anterior circulation PTs (GA: 69 (44-100); CS: 59 (37-99); p=0.235), FTs (GA: 33 (20-56); CS: 29 (16-51); p=0.286), and RE (DAP, GA: 116.23 (73.47-173.41); CS: 110.5 (68.35-184.65); p=0.929) were comparable. In a subgroup analysis of occlusions of the middle cerebral artery (M1-segment; GA: n=80/544, 14.7%; CS: n=211/544, 38.8%), PTs (GA: 69 (37-101); CS: 54 (35 - 89); p=0.223), FTs (GA: 33 (19-55); CS: 25 (14-48); p=0.264), and RE (DAP, GA: 110.91 (66.8-169.12); CS: 103.8 (63.17-181); p=0.893) were similar. CONCLUSION: In this retrospective analysis, no effect of the mode of anesthesia on the radiation exposure during EST was detected as GA and CS showed comparable PT, FT, and DAPs.

Asymptomatic Carotid Stenosis: Intervention or Best Medical Therapy?

PURPOSE OF REVIEW: Provide a current overview regarding the optimal strategy for managing patients with asymptomatic carotid artery stenosis. RECENT FINDINGS: Carotid endarterectomy (CEA) and carotid artery stenting (CAS) reduce long-term stroke risk in asymptomatic patients. However, CAS is associated with a higher risk of peri-procedural stroke. Improvements in best medical therapy (BMT) have renewed uncertainty regarding the extent to which results from older randomised controlled trials (RCTs) comparing outcomes following carotid intervention can be generalised to modern medical practise. 'Average surgical risk' patients with an asymptomatic carotid artery stenosis of 60-99% and increased risk of late stroke should be considered for either CEA or CAS. In patients deemed 'high risk' for surgery, CAS is indicated. Use of an anti-platelet, anti-hypertensive and statin, with strict glycaemic control, is recommended. Results from ongoing large, multicentre RCTs comparing CEA, CAS and BMT will provide clarity regarding the optimal management of patients with asymptomatic carotid artery stenosis.

Influence of stent design and use of protection devices on outcome of carotid artery stenting: a pooled analysis of individual patient data.

BACKGROUND AND PURPOSE: Carotid artery stenting is an alternative to endarterectomy for the treatment of symptomatic carotid stenosis but was associated with a higher risk of procedural stroke or death in randomized controlled trials (RCTs). Technical aspects of treatment may partly explain these results. The purpose of this analysis was to investigate the influence of technical aspects such as stent design or the use of protection devices, as well as clinical variables, on procedural risk. METHODS: We pooled data of 1557 individual patients receiving stent treatment in three large RCTs comparing stenting versus endarterectomy for symptomatic carotid stenosis. The primary outcome event was any procedural stroke or death occurring within 30 days after stenting. RESULTS: Procedural stroke or death occurred significantly more often with the use of open-cell stents (61/595 patients, 10.3%) than with closed-cell stents (58/962 patients, 6.0%; RR 1.76; 95% CI 1.23 to 2.52; P=0.002). Procedural stroke or death occurred in 76/950 patients (8.0%) treated with protection devices (predominantly distal filters) and in 43/607 (7.1%) treated without protection devices (RR 1.10; 95% CI 0.71 to 1.70; P=0.67). Clinical variables predicting the primary outcome event were age, severity of the qualifying event, history of prior stroke, and level of disability at baseline. The effect of stent design remained similar after adjustment for these variables. CONCLUSIONS: In symptomatic carotid stenosis, the use of stents with a closed-cell design is independently associated with a lower risk of procedural stroke or death compared with open-cell stents. Filter-type protection devices do not appear to reduce procedural risk.

Effect of General Anesthesia versus Conscious Sedation for Stroke Thrombectomy on Angiographic Workflow in a Randomized Trial: A Post Hoc Analysis of the SIESTA Trial.

Purpose To investigate whether the sedation mode (ie, conscious sedation [CS] vs general anesthesia [GA]) affects the angiographic workflow applied for treatment of endovascular stroke in a post hoc analysis of a recent randomized controlled trial, Sedation versus Intubation for Endovascular Stroke Treatment (SIESTA). Materials and Methods SIESTA was an institutional review board-approved, single-center, prospective, randomized, parallel-group, open-label treatment trial with a blinded end-point evaluation to compare GA with CS for treatment of endovascular stroke in 73 and 77 patients, respectively. By using descriptive data from SIESTA, the influence of the mode of sedation on angiographic workflow during treatment for endovascular stroke (eg, procedure times) and other radiologic outcome parameters (eg, radiation exposure) were analyzed. The time between angiographic key steps for patients who underwent GA and CS was evaluated with t tests. P values were corrected for false discovery rate. Results The median time from groin puncture to first intracranial flow restoration with CS was 47 minutes (interquartile range [IQR], 29-70 minutes), and for GA, it was 41 minutes (IQR, 28-60 minutes) (P = .546). The median time to the end of angiography with CS was 104 minutes (IQR, 75-150 minutes), and with GA, it was 73 minutes (IQR, 53-125 minutes) (P = .052). Fluoroscopy time with CS was 49 minutes (IQR, 25-85 minutes), and with GA, it was 35 minutes (IQR, 20-74 minutes) (P = .098). The times were comparable in both groups for these measures. The time from groin puncture to the final angiographic result with GA, at 72 minutes (IQR, 45-109 minutes) was shorter than that with CS, at 98 minutes (IQR, 64-135 minutes) (P = .048). Conclusion This post hoc analysis of the single-center SIESTA trial revealed that time from groin puncture to final angiographic result was shorter with patients under GA than that with patients under CS. © RSNA, 2017 Online supplemental material is available for this article.

Early Endarterectomy Carries a Lower Procedural Risk Than Early Stenting in Patients With Symptomatic Stenosis of the Internal Carotid Artery: Results From 4 Randomized Controlled Trials.

BACKGROUND AND PURPOSE: Patients undergoing carotid endarterectomy (CEA) for symptomatic stenosis of the internal carotid artery benefit from early intervention. Heterogeneous data are available on the influence of timing of carotid artery stenting (CAS) on procedural risk. METHODS: We investigated the association between timing of treatment (0-7 days and >7 days after the qualifying neurological event) and the 30-day risk of stroke or death after CAS or CEA in a pooled analysis of individual patient data from 4 randomized trials by the Carotid Stenosis Trialists' Collaboration. Analyses were done per protocol. To obtain combined estimates, logistic mixed models were applied. RESULTS: Among a total of 4138 patients, a minority received their allocated treatment within 7 days after symptom onset (14% CAS versus 11% CEA). Among patients treated within 1 week of symptoms, those treated by CAS had a higher risk of stroke or death compared with those treated with CEA: 8.3% versus 1.3%, risk ratio, 6.7; 95% confidence interval, 2.1 to 21.9 (adjusted for age at treatment, sex, and type of qualifying event). For interventions after 1 week, CAS was also more hazardous than CEA: 7.1% versus 3.6%, adjusted risk ratio, 2.0; 95% confidence interval, 1.5 to 2.7 (P value for interaction with time interval 0.06). CONCLUSIONS: In randomized trials comparing stenting with CEA for symptomatic carotid artery stenosis, CAS was associated with a substantially higher periprocedural risk during the first 7 days after the onset of symptoms. Early surgery is safer than stenting for preventing future stroke. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00190398; URL: http://www.controlled-trials.com. Unique identifier: ISRCTN57874028; Unique identifier: ISRCTN25337470; URL: http://www.clinicaltrials.gov. Unique identifier: NCT00004732.

Combined proximal balloon occlusion and distal aspiration: a new approach to prevent distal embolization during neurothrombectomy.

BACKGROUND AND PURPOSE: Embolization of thrombus fragments in a new vascular territory is a potential adverse event in neurothrombectomy. This study was performed to evaluate the safety and feasibility of a novel approach combining proximal balloon occlusion and distal aspiration to prevent distal thrombembolic complications. METHODS: Patients with ischemic stroke meeting the following inclusion criteria were eligible: occlusion in the anterior circulation, neurothrombectomy using a balloon catheter for proximal flow arrest, and an intermediate catheter for distal aspiration. Pre- and post-interventional Thrombolysis In Cerebral Infarction (TICI) scores were assessed. Clinical presentation at admission and discharge and after 3 months was also evaluated and complications (particularly new thrombembolic events) were recorded. RESULTS: We retrospectively identified 31 patients from our prospectively collected stroke database who met the inclusion criteria. In all patients the initial TICI was 0. A TICI score of ≥2b was achieved in 96.8%. No new thrombembolic complications occurred. The median NIH Stroke Scale score was 19 at admission and 4.5 at discharge. After 3 months, 51.6% of the patients had a favorable clinical outcome (modified Rankin Scale score 0-2) and 19.3% had died. CONCLUSIONS: A combination of proximal internal carotid artery occlusion using a balloon catheter and distal aspiration through an intermediate catheter represents a safe and efficient adjunct to mechanical thrombectomy with stent retrievers. In our patient cohort, no new thrombembolic complications were detected.

Mechanical thrombectomy using a combined CT/C-arm X-ray system.

BACKGROUND: Mechanical thrombectomy (MT) using stent-retrievers has been proven to be a safe and effective treatment in acute ischemic stroke (AIS), particularly in large vessel occlusion. Other than patient characteristics, time to recanalization is the most important factor linked to outcome. MT is usually performed in a dedicated angiography suite using a floor- and/or ceiling-mounted biplane angiographic system. Here we report our first experience of MT with a new combined CT and mobile C-arm X-ray device setup. METHODS: Patients with AIS underwent stroke imaging (non-contrast enhanced CT, CT perfusion, and CT angiography) using a commercially available 64-slice CT scanner which was modified for combined use with a C-arm system. In patients with large vessel occlusion, MT was conducted without further patient transfer within the CT imaging suite using a mobile C-arm X-ray device equipped with a 30×30 cm (12×12 inch), 1.5×1.5 k full-view flat detector which was positioned between the gantry and patient table. The safety and feasibility of this new system was assessed in preliminary patients. RESULTS: Angiographic imaging quality of the mobile C-arm was feasible and satisfactory for diagnostic angiography and MT. Using this setup, time between stroke imaging and groin puncture (picture-to-puncture time) was reduced by up to 35 min (including time for preparation of the patient such as intubation). CONCLUSIONS: MT using a combined CT/C-arm system is safe and feasible. The potential advantages, particularly time saving and ensuing improvement in patient outcome, need to be assessed in a larger study.

Carotid stenting: is there an operator effect? A pooled analysis from the carotid stenting trialists' collaboration.

BACKGROUND AND PURPOSE: Randomized clinical trials show higher 30-day risk of stroke or death after carotid artery stenting compared with surgery. We examined whether operator experience is associated with 30-day risk of stroke or death in the Carotid Stenting Trialists' Collaboration database. METHODS: The Carotid Stenting Trialists' Collaboration is a pooled individual patient database including all patients recruited in 3 randomized trials of stenting versus endarterectomy for symptomatic carotid stenosis (Endarterectomy Versus Angioplasty in patients with Symptomatic Severe Carotid Stenosis trial, Stent-Protected Angioplasty versus Carotid Endarterectomy trial, and International Carotid Stenting Study). Lifetime carotid artery stenting experience, lifetime experience in stenting procedures excluding the carotid, and annual number of procedures performed within the trial (in-trial volume), divided into tertiles, were used to measure operator experience. The outcome event was the occurrence of any stroke or death within 30 days of the procedure. The analysis was done per protocol. RESULTS: Among 1546 patients who underwent carotid artery stenting, 120 (7.8%) had a stroke or death within 30 days of the procedure. The 30-day risk of stroke or death did not differ according to operator lifetime carotid artery stenting experience (P=0.8) or operator lifetime stenting experience excluding the carotid (P=0.7). In contrast, the 30-day risk of stroke or death was significantly higher in patients treated by operators with low (mean ≤3.2 procedures/y; risk 10.1%; adjusted risk ratio=2.30 [1.36-3.87]) and intermediate annual in-trial volumes (3.2-5.6 procedures/y; 8.4%; adjusted risk ratio=1.93 [1.14-3.27]) compared with patients treated by high annual in-trial volume operators (>5.6 procedures/y; 5.1%). CONCLUSIONS: Carotid stenting should only be performed by operators with annual procedure volume ≥6 cases per year.

The diagnosis, treatment and follow-up of extracranial carotid stenosis.

BACKGROUND: Extracranial atherosclerotic lesions of the carotid bifurcation cause 10% to 20% of all cases of cerebral ischemia. Until now, there have been no comprehensive evidence- and consensus-based recommendations for the management of patients with extracranial carotid stenosis in Germany and Austria. METHODS: The literature was systematically searched for pertinent publications (1990-2011). On the basis of 182 randomized clinical trials (RCTs) and 308 systematic reviews, 30 key questions were answered and evidence-based recommendations were issued. RESULTS: The prevalence of extracranial carotid stenosis is more than 5% from age 65 onward. Men are affected twice as frequently as women. The most important diagnostic technique is Doppler- and color-coded duplex ultrasonography. RCTs have shown that the treatment of high-grade asymptomatic carotid stenosis with carotid endarterectomy (CEA) can lower the 5-year risk of stroke from 11% to 5%. Intensive conservative treatment may lower the stroke risk still further. Moreover, RCTs have shown that CEA for symptomatic 50% to 99% carotid stenosis lowers the 5-year stroke risk by 5% to 16%. Meta-analyses of the 13 available RCTs comparing carotid artery stenting (CAS) with CEA have shown that CAS is associated with a 2% to 2.5% higher risk of periprocedural stroke or death and with a 0.5% to 1% lower risk of periprocedural myocardial infarction. If no particular surgical risk factors are present, CEA is the standard treatment for high-grade carotid stenosis. CAS may be considered as an alternative to CEA if the rate of procedure-related stroke or death can be kept below 3% or 6% for asymptomatic and symptomatic stenosis, respectively. CONCLUSION: Further studies are needed so that better selection criteria can be developed for individually tailored treatment.

Safety of thrombolysis in stroke mimics: results from a multicenter cohort study.

BACKGROUND AND PURPOSE: Intravenous thrombolysis for acute ischemic stroke is beneficial within 4.5 hours of symptom onset, but the effect rapidly decreases over time, necessitating quick diagnostic in-hospital work-up. Initial time strain occasionally results in treatment of patients with an alternate diagnosis (stroke mimics). We investigated whether intravenous thrombolysis is safe in these patients. METHODS: In this multicenter observational cohort study containing 5581 consecutive patients treated with intravenous thrombolysis, we determined the frequency and the clinical characteristics of stroke mimics. For safety, we compared the symptomatic intracranial hemorrhage (European Cooperative Acute Stroke Study II [ECASS-II] definition) rate of stroke mimics with ischemic strokes. RESULTS: One hundred stroke mimics were identified, resulting in a frequency of 1.8% (95% confidence interval, 1.5-2.2). Patients with a stroke mimic were younger, more often female, and had fewer risk factors except smoking and previous stroke or transient ischemic attack. The symptomatic intracranial hemorrhage rate in stroke mimics was 1.0% (95% confidence interval, 0.0-5.0) compared with 7.9% (95% confidence interval, 7.2-8.7) in ischemic strokes. CONCLUSIONS: In experienced stroke centers, among patients treated with intravenous thrombolysis, only a few had a final diagnosis other than stroke. The complication rate in these stroke mimics was low.

Cerebral amyloid angiopathy--an underdiagnosed entity in younger adults with lobar intracerebral hemorrhage?

Cerebral amyloid angiopathy (CAA) is a progressive microvascular amyloidosis affecting the small- and medium-sized arterioles and the capillaries of brain parenchyma and leptomeninges, and is recognized as a cause of lobar intracerebral hemorrhage (ICH). We report two patients who experienced recurrent ICH due to CAA at an age of 37 (A) and 42 (B) years, respectively. The classic and modified Boston criteria for the diagnosis of CAA include an age limit of 55 years if no biopsy or postmortem examination is performed; CAA is typically not considered in the differential diagnosis of lobar ICH in younger patients. We assume that sporadic CAA is an underdiagnosed entity in younger adults with lobar ICH.

The risk of carotid artery stenting compared with carotid endarterectomy is greatest in patients treated within 7 days of symptoms.

OBJECTIVE: Among patients with symptomatic carotid artery stenosis, carotid artery stenting (CAS) is associated with a higher risk of periprocedural stroke or death than carotid endarterectomy (CEA). Uncertainty remains whether the balance of risk changes with time since the most recent ischemic event. METHODS: We investigated the association of time between the qualifying ischemic event and treatment (0-7 days, 8-14 days, and >14 days) with the risk of stroke or death within 30 days after CAS or CEA in a pooled analysis of data from individual patients randomized in the Endarterectomy vs Angioplasty in Patients with Symptomatic Severe Carotid Stenosis (EVA-3S) trial, the Stent-Protected Angioplasty versus Carotid Endarterectomy (SPACE) trial, and the International Carotid Stenting Study (ICSS). Data were analyzed with a fixed-effect binomial regression model adjusted for source trial. RESULTS: Information on time of qualifying event was available for 2839 patients. In the first 30 days after intervention, any stroke or death occurred significantly more often in the CAS group (110/1434 [7.7%]) compared with the CEA group (54/1405 [3.8%]; crude risk ratio, 2.0; 95% confidence interval, 1.5-2.7). Patients undergoing CEA within the first 7 days of the qualifying event had the lowest periprocedural stroke or death rate (3/106 [2.8%]). Patients treated with CAS in the same period had a 9.4% risk of periprocedural stroke or death (13/138; risk ratio CAS vs CEA: 3.4; 95% confidence interval, 1.01-11.8; adjusted for age, sex, and type of qualifying event). Patients treated between 8 and 14 days showed a periprocedural stroke or death rate of 3.4% (7/208) and 8.1% (19/234), respectively, for CEA and CAS. The latest treatment group had 4% complications in the CEA group (44/1091) and 7.3% in the CAS group (78/1062). CONCLUSIONS: The increase in risk of CAS compared with CEA appears to be greatest in patients treated within 7 days of symptoms. Early surgery might remain most effective in stroke prevention in patients with symptomatic carotid artery stenosis.

Herpes simplex virus encephalitis despite normal cell count in the cerebrospinal fluid.

OBJECTIVES: To describe herpes simplex virus encephalitis despite normal cell count in the cerebrospinal fluid in patients with malignoma after whole brain irradiation. INTERVENTIONS: Blood and cerebrospinal fluid analysis and magnetic resonance imaging. MEASUREMENTS AND MAIN RESULTS: Three male and two female patients with malignoma and a recent history of whole-brain irradiation presented with impaired consciousness with or without epileptic seizure. Although cerebrospinal fluid analysis revealed a normal cell count, herpes simplex virus DNA was detected in all samples by polymerase chain reaction. CONCLUSIONS: In patients with impaired consciousness, epileptic seizure, or temporal lobe symptoms of new onset and a recent history of brain irradiation with normal cerebrospinal fluid, an atypical anergic course of herpes simplex virus encephalitis should be considered. Herpes simplex virus polymerase chain reaction should be used as method of choice to detect herpes simplex virus genomes as early as possible rather than relying on routine cerebrospinal fluid parameters. Importantly, antiviral therapy should be started without delay in any case of faint suspicion and should be continued until herpes simplex virus encephalitis is clearly ruled out.

Long-term outcome after surgical treatment for space-occupying cerebellar infarction: experience in 56 patients.

BACKGROUND AND PURPOSE: Surgical management of space-occupying cerebellar infarction is still controversial. Data on long-term outcome are lacking. The objective of this study was (1) to evaluate outcome after at least 3 years poststroke in patients with space-occupying cerebellar infarction treated by ventriculostomy/extraventricular drainage (EVD) or suboccipital decompressive craniectomy (SDC), or both, and (2) to determine predicting factors for outcome. METHODS: In this retrospective single-center study 56 consecutive patients with acute space-occupying cerebellar infarction treated surgically between 1996 and 2005 were included. Baseline data included clinical findings, Glasgow Coma Scale on admission and before surgery, NIHSS on admission, mass effects on neuroimaging, and surgical treatment strategies. Modified Rankin Scale, NIHSS, and Scale for the Assessment and Rating of Ataxia were used to assess outcome. RESULTS: 39.3% of patients had died, 51.8% had a mRS < or =3, 35.7% had a mRS < or =2, 28.6% had a mRS < or =1. There were no significant differences in survival between treatment groups. In multivariate analysis age and mRS score at discharge were the most evident independent predictors for outcome. CONCLUSIONS: So far this is the largest study on long-term outcome after space-occupying cerebellar infarction. The value of different treatment strategies and prognostic factors for patient selection remain unclear and should be evaluated in larger prospective case-series or registries. To investigate the issue of preventive SDC randomized trials are needed.