Differences and similarities between spontaneous dissections of the internal carotid artery and the vertebral artery.

BACKGROUND AND PURPOSE: To compare potential risk factors, clinical symptoms, diagnostic delay, and 3-month outcome between spontaneous internal carotid artery dissection (sICAD) and spontaneous vertebral artery dissection (sVAD). METHODS: We compared patients with sICAD (n=668) and sVAD (n=302) treated in 3 university hospitals. RESULTS: Patients with sICAD were older (46.3 ± 9.6 versus 42.0 ± 10.2 years; P<0.001), more often men (62.7% versus 53.0%; P=0.004), and presented more frequently with tinnitus (10.9% versus 3.4%; P<0.001) and more severe ischemic strokes (median National Institutes of Health Stroke Scale, 10 ± 7.1 versus 5 ± 5.9; P<0.001). Patients with sVAD had more often bilateral dissections (15.2% versus 7.6%; P<0.001) and were more often smokers (36.0% versus 28.7%; P=0.007). Thunderclap headache (9.2% versus 3.6%; P=0.001) and neck pain were more common (65.8% versus 33.5%; P<0.001) in sVAD. Subarachnoid hemorrhage (6.0% versus 0.6%; P<0.001) and ischemic stroke (69.5% versus 52.2%; P<0.001) were more frequent in sVAD. After multivariate analysis, sex difference lost its significance (P=0.21), and all other variables remained significant. Time to diagnosis was similar in sICAD and sVAD and improved between 2001 and 2012 compared with the previous 10-year period (8.0 ± 10.5 days versus 10.7 ± 13.2 days; P=0.004). In sVAD, favorable outcome 3 months after ischemic stroke (modified Rankin Scale, 0-2: 88.8% versus 58.4%; P<0.001), recurrent transient ischemic attack (4.8% versus 1.1%; P=0.001), and recurrent ischemic stroke (2.8% versus 0.7%; P=0.02) within 3 months were more frequent. CONCLUSIONS: sICAD and sVAD patients differ in many aspects. Future studies should perform separate analyses of these 2 entities.

The ocular pulse amplitude as a noninvasive parameter for carotid artery stenosis screening: a test accuracy study.

PURPOSE: To investigate a potential correlation between the ocular pulse amplitude (OPA; i.e., the intraocular pressure difference between the systolic and diastolic phases of the heartbeat) and the severity of carotid artery stenosis (CAS) and to test its role as a screening parameter for CAS during routine ophthalmic examination. DESIGN: Test accuracy study. PARTICIPANTS: Patients referred for color duplex ultrasound examination of the extra- and intracranial cerebral arteries were enrolled consecutively. METHODS: We measured OPA on both eyes by dynamic contour tonometry. Multivariate analyses were performed with risk factors for CAS (age, total cholesterol, low-density lipoprotein, and triglycerides) to compare the diagnostic value of OPA measurements with other non- or minimally invasive screening parameters. MAIN OUTCOME MEASURES: The difference between OPA measurements in patients with no (<50%) and patients with severe CAS (>70%) as well as the value of OPA measurements to predict the severity of CAS taking further risk factors of CAS into consideration. RESULTS: One hundred thirty-four eyes of 67 patients (25 women, 42 men) with a mean age of 67±13 years (range, 25-87) were included. The means of the OPA values of those patients showing no CAS (<50%) differed significantly (P = 0.036) from those with a stenosis of ≥70%. The multivariate model produced a statistically significant odds ratio (0.46; P = 0.007) for CAS of ≥70%. CONCLUSIONS: The results of the present study provide proof of principle that the OPA is reduced in patients with CAS and may be used as a noninvasive, inexpensive, readily available, and unconfounded screening parameter to detect CAS and possibly to reduce the incidence of stroke. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any of the materials discussed in this article.

Carotid plaque surface echogenicity predicts cerebrovascular events: An Echographic Multicentric Swiss Study.

BACKGROUND AND PURPOSE: To determine the prognostic value for ischemic stroke or transitory ischemic attack (TIA) of plaque surface echogenicity alone or combined to degree of stenosis in a Swiss multicenter cohort METHODS: Patients with ≥60% asymptomatic or ≥50% symptomatic carotid stenosis were included. Grey-scale based colour mapping was obtained of the whole plaque and of its surface defined as the regions between the lumen and respectively 0-0.5, 0-1, 0-1.5, and 0-2 mm of the outer border of the plaque. Red, yellow and green colour represented low, intermediate or high echogenicity. Proportion of red color on surface (PRCS) reflecting low echogenictiy was considered alone or combined to degree of stenosis (Risk index, RI). RESULTS: We included 205 asymptomatic and 54 symptomatic patients. During follow-up (median/mean 24/27.7 months) 27 patients experienced stroke or TIA. In the asymptomatic group, RI ≥0.25 and PRCS ≥79% predicted stroke or TIA with a hazard ratio (HR) of respectively 8.7 p = 0.0001 and 10.2 p < 0.0001. In the symptomatic group RI ≥0.25 and PRCS ≥81% predicted stroke or TIA occurrence with a HR of respectively 6.1 p = 0.006 and 8.9 p = 0.001. The best surface parameter was located at 0-0.5mm. Among variables including age, sex, degree of stenosis, stenosis progression, RI, PRCS, grey median scale values and clinical baseline status, only PRCS independently prognosticated stroke (p = 0.005). CONCLUSION: In this pilot study including patients with at least moderate degree of carotid stenosis, PRCS (0-0.5mm) alone or combined to degree of stenosis strongly predicted occurrence of subsequent cerebrovascular events.

Impact of obesity on stroke outcome after intravenous thrombolysis.

BACKGROUND AND PURPOSE: Obesity is an established risk factor for stroke and has reached epidemic proportions. However, its impact on intravenous thrombolysis applied for acute ischemic stroke is not well known. We aimed to compare the clinical outcome and safety after intravenous thrombolysis in obese (body mass index ≥30 kg/m²) and nonobese (body mass index <30 kg/m²) patients with ischemic stroke. METHODS: Data of 304 consecutive patients with stroke (251 nonobese and 53 obese) treated with intravenous thrombolysis were studied. We assessed the rate of favorable outcome (modified Rankin Scale score 0 or 1), mortality, and symptomatic intracranial hemorrhage in the 2 groups. RESULTS: Obese patients presented more often with diabetes mellitus (30.2% versus 12.4%, P<0.01) and arterial hypertension (77.4% versus 61.4%, P=0.03) as compared with their nonobese counterparts. At 3 months, the rate of favorable outcome was lower in obese compared with nonobese patients (50.9% versus 68.1%, P=0.02). More obese than nonobese patients died (13.2% versus 4.0%, P=0.01), whereas the rate of symptomatic intracranial hemorrhage was similar in the 2 groups (1.9% versus 1.6%, P=1.0). After multivariable adjustment, obesity still remained an independent predictor of unfavorable outcome (P=0.04) and mortality (P=0.04). CONCLUSIONS: Our data indicate that obesity is an independent predictor of unfavorable clinical outcome and mortality in acute ischemic stroke treated with intravenous thrombolysis.

Intravenous thrombolysis in nonagenarians with ischemic stroke.

BACKGROUND AND PURPOSE: Demographic changes will result in a rapid increase of patients age ≥90 years (nonagenarians), but little is known about outcomes in these patients after intravenous thrombolysis (IVT) for acute ischemic stroke. We aimed to assess safety and functional outcome in nonagenarians treated with IVT and to compare the outcomes with those of patients age 80 to 89 years (octogenarians). METHODS: We analyzed prospectively collected data of 284 consecutive stroke patients age ≥80 years treated with IVT in 7 Swiss stroke units. Presenting characteristics, favorable outcome (modified Rankin scale [mRS] 0 or 1), mortality at 3 months, and symptomatic intracranial hemorrhage (SICH) using the National Institute of Neurological Disorders and Stroke (NINDS) and Safe Implementation of Thrombolysis in Stroke-Monitoring Study (SITS-MOST) criteria were compared between nonagenarians and octogenarians. RESULTS: As compared with octogenarians (n=238; mean age, 83 years), nonagenarians (n=46; mean age, 92 years) were more often women (70% versus 54%; P=0.046) and had lower systolic blood pressure (161 mm Hg versus 172 mm Hg; P=0.035). Patients age ≥90 years less often had a favorable outcome and had a higher incidence of mortality than did patients age 80 to 89 years (14.3% versus 30.2%; P=0.034; and 45.2% versus 22.1%; P=0.002; respectively), while more nonagenarians than octogenarians experienced a SICH (SICH(NINDS), 13.3% versus 5.9%; P=0.106; SICH(SITS-MOST), 13.3% versus 4.7%; P=0.037). Multivariate adjustment identified age ≥90 years as an independent predictor of mortality (P=0.017). CONCLUSIONS: Our study suggests less favorable outcomes in nonagenarians as compared with octogenarians after IVT for ischemic stroke, and it demands a careful selection for treatment, unless randomized controlled trials yield more evidence for IVT in very old stroke patients.

Outcomes of intravenous thrombolysis in posterior versus anterior circulation stroke.

BACKGROUND AND PURPOSE: Intravenous thrombolysis is an approved treatment for anterior (ACS) and posterior (PCS) circulation stroke. However, no randomized controlled trial has investigated safety and efficacy of intravenous thrombolysis according to stroke territory, although PCS is assumed to differ from ACS in many ways. We aimed to compare the safety and clinical outcome of intravenous thrombolysis applied to patients with PCS and ACS. METHODS: Prospectively collected data of 883 consecutive patients with acute ischemic stroke (788 ACS, 95 PCS) treated with intravenous thrombolysis in 3 Swiss stroke centers were analyzed. Presenting characteristics, symptomatic intracranial hemorrhage, mortality, and favorable outcome (modified Rankin scale 0 or 1) at 3 months were compared between patients with PCS and ACS. RESULTS: As compared with patients with ACS, those with PCS were younger (mean age, 63 versus 67 years, P=0.012) and had a lower mean baseline National Institutes of Health Stroke Scale score (9 versus 12, P<0.001). Patients with PCS less often had symptomatic intracranial hemorrhage (0% versus 5%, P=0.026) and had more often a favorable outcome (66% versus 47%, P<0.001). Mortality was similar in the 2 groups (PCS, 9%; ACS, 13%; P=0.243). After multivariable adjustment, PCS was an independent predictor of lower symptomatic intracranial hemorrhage frequency (P=0.001), whereas stroke territory was not associated either with favorable outcome (P=0.177) or with mortality (P=0.251). CONCLUSIONS: Our study suggests that PCS is associated with a lower risk of symptomatic intracranial hemorrhage after intravenous thrombolysis as compared with ACS, whereas favorable outcome and mortality were similar in the 2 stroke territories.

Safety and functional outcome of thrombolysis in dissection-related ischemic stroke: a meta-analysis of individual patient data.

BACKGROUND AND PURPOSE: The safety and efficacy of thrombolysis in cervical artery dissection (CAD) are controversial. The aim of this meta-analysis was to pool all individual patient data and provide a valid estimate of safety and outcome of thrombolysis in CAD. METHODS: We performed a systematic literature search on intravenous and intra-arterial thrombolysis in CAD. We calculated the rates of pooled symptomatic intracranial hemorrhage and mortality and indirectly compared them with matched controls from the Safe Implementation of Thrombolysis in Stroke-International Stroke Thrombolysis Register. We applied multivariate regression models to identify predictors of excellent (modified Rankin Scale=0 to 1) and favorable (modified Rankin Scale=0 to 2) outcome. RESULTS: We obtained individual patient data of 180 patients from 14 retrospective series and 22 case reports. Patients were predominantly female (68%), with a mean±SD age of 46±11 years. Most patients presented with severe stroke (median National Institutes of Health Stroke Scale score=16). Treatment was intravenous thrombolysis in 67% and intra-arterial thrombolysis in 33%. Median follow-up was 3 months. The pooled symptomatic intracranial hemorrhage rate was 3.1% (95% CI, 1.3 to 7.2). Overall mortality was 8.1% (95% CI, 4.9 to 13.2), and 41.0% (95% CI, 31.4 to 51.4) had an excellent outcome. Stroke severity was a strong predictor of outcome. Overlapping confidence intervals of end points indicated no relevant differences with matched controls from the Safe Implementation of Thrombolysis in Stroke-International Stroke Thrombolysis Register. CONCLUSIONS: Safety and outcome of thrombolysis in patients with CAD-related stroke appear similar to those for stroke from all causes. Based on our findings, thrombolysis should not be withheld in patients with CAD.

Wall stress of the cervical carotid artery in patients with carotid dissection: a case-control study.

Spontaneous internal carotid artery (ICA) dissection (sICAD) results from an intimal tear located around the distal carotid sinus. The mechanisms causing the tear are unknown. This case-control study tested the hypotheses that head movements increase the wall stress in the cervical ICA and that the stress increase is greater in patients with sICAD than in controls. Five patients with unilateral, recanalized, left sICAD and five matched controls were investigated before and after maximal head rotation to the left and neck hyperextension after 45° head rotation to the left. The anatomy of the extracranial carotid arteries was assessed by magnetic resonance imaging and used to create finite element models of the right ICA. Wall stress increased after head movements. Increases above the 80th and 90th percentile were located at the intimal side of the artery wall from 7.4 mm below to 10 mm above the cranial edge of the carotid sinus, i.e., at the same location as histologically confirmed tears in patients with sICAD. Wall stress increase did not differ between patients and controls. The present findings suggest that wall stress increases at the intimal side of the artery wall surrounding the distal edge of the carotid bulb after head movements may be important for the development of carotid dissection. The lack of wall stress difference between the two groups indicates that the carotid arteries of patients with carotid dissection have either distinct functional or anatomical properties or endured unusually heavy wall stresses to initiate dissection.

Differences in demographic characteristics and risk factors in patients with spontaneous vertebral artery dissections with and without ischemic events.

BACKGROUND AND PURPOSE: Spontaneous vertebral artery dissection (sVADs) mainly cause cerebral ischemia, with or without associated local symptoms and signs (headache, neck pain, or cervical radiculopathy), or with local symptoms and signs only. METHODS: We compared the presenting characteristics of consecutive patients with single sVADs and ischemic events and those with local symptoms and signs only. RESULTS: Of the 186 patients with first-ever unilateral sVAD, 165 (89%) presented with cerebral ischemia, and 21 (11%) presented with local symptoms and signs only. Patients with sVAD and ischemia were more often male (63% vs 29%; P=0.002), older (mean+/-SD age, 43.6+/-9.9 vs 38.6+/-9.0 years; P=0.027), and smokers (14% vs 3%; P=0.010), but less often, they had a history of migraine without aura (17% vs 38%; P=0.025) than did patients without ischemia. The multivariate analysis confirmed independent associations between male sex (P=0.024), increasing age (0.027), and smoking (P=0.012) and sVADs causing cerebral ischemia. CONCLUSIONS: These results suggest that men, older patients, and smokers with sVADs may be at increased risk for ischemic events.

Emerging concepts in acute mountain sickness and high-altitude cerebral edema: from the molecular to the morphological.

Acute mountain sickness (AMS) is a neurological disorder that typically affects mountaineers who ascend to high altitude. The symptoms have traditionally been ascribed to intracranial hypertension caused by extracellular vasogenic edematous brain swelling subsequent to mechanical disruption of the blood-brain barrier in hypoxia. However, recent diffusion-weighted magnetic resonance imaging studies have identified mild astrocytic swelling caused by a net redistribution of fluid from the "hypoxia-primed" extracellular space to the intracellular space without any evidence for further barrier disruption or additional increment in brain edema, swelling or pressure. These findings and the observation of minor vasogenic edema present in individuals with and without AMS suggest that the symptoms are not explained by cerebral edema. This has led to a re-evaluation of the relevant pathogenic events with a specific focus on free radicals and their interaction with the trigeminovascular system.

Management of spontaneous dissection of the cervical carotid artery.

This manuscript reviews the management of patients with spontaneous dissection of the cervical internal carotid artery (sICAD). Recommendations are not based on controlled-randomized trials, but on case-control and observational, hospital-based studies, and case reports. Vascular risk factors seem to be as prevalent in patients with sICAD as in age-matched, healthy volunteers. Stroke prevention includes the treatment of vascular risk factors and the administration of oral aspirin, which may be as effective as anticoagulation. The few available data indicate that most patients with sICAD causing severe stenosis or occlusion, or an aneurysm can be treated conservatively. Patients with sICAD were not excluded in the intravenous controlled-randomized thrombolysis trials with tissue plasminogen activator, but were excluded in the intraarterial controlled-randomized thrombolysis trials. Taking the few published case series and reports on thrombolysis in patients with sICAD into consideration, intravenous thrombolysis may be beneficial, whereas it remains unclear whether intraarterial thrombolysis is useful.

Impact of intravenous thrombolysis on functional outcome in patients with mild ischemic stroke without large vessel occlusion or rapidly improving symptoms.

BACKGROUND: Optimal treatment strategy in patients with mild ischemic stroke remains uncertain. While functional dependency or death has been reported in up to one-third of non-thrombolyzed mild ischemic stroke patients, intravenous thrombolysis is currently not recommended in this patient group. Emerging evidence suggests two risk factors-rapid early improvement and large vessel occlusion-as main associates of unfavorable outcome in mild ischemic stroke patients not undergoing intravenous thrombolysis. AIMS: To analyze natural course as well as safety and three-month outcome of intravenous thrombolysis in mild ischemic stroke without rapid early improvement or large vessel occlusion. METHODS: Mild ischemic stroke was defined by a National Institute of Health Stroke Scale score ≤6. We used the modified Rankin Scale (mRS) to compare three-month functional outcome in 370 consecutive mild ischemic stroke patients without early rapid improvement and without large vessel occlusion, who either underwent intravenous thrombolysis (n = 108) or received best medical treatment (n = 262). RESULTS: Favorable outcome (mRS ≤ 1) was common in both groups (intravenous thrombolysis: 91%; no intravenous thrombolysis: 90%). Although intravenous thrombolysis use was independently associated with a higher risk of asymptomatic hemorrhagic transformation (OR = 4.62, p = 0.002), intravenous thrombolysis appeared as an independent predictor of mRS = 0 at three months (OR = 3.33, p < 0.0001). CONCLUSIONS: Mild ischemic stroke patients without rapidly improving symptoms and without large vessel occlusion have a high chance of favorable three-month outcome, irrespective of treatment type. Patients receiving intravenous thrombolysis, however, more often achieved complete remission of symptoms, which particularly in mild ischemic stroke may constitute a meaningful endpoint.

R2-recanalization of spontaneous carotid artery dissection.

BACKGROUND AND PURPOSE: We set out to investigate the predictors and time course for recanalization of spontaneous dissection of the cervical internal carotid artery (SICAD). METHODS: We prospectively included 249 consecutive patients (mean age, 45+/-11 years) with 268 SICAD. Ultrasound examinations were performed at presentation, during the first month, and then at 3, 6, and 12 months, and clinical follow-ups after 3, 6, and 12 months. RESULTS: Of 268 SICADs, 20 (7.5%) presented with

Consensus recommendations for transcranial color-coded duplex sonography for the assessment of intracranial arteries in clinical trials on acute stroke.

BACKGROUND AND PURPOSE: Transcranial color-coded duplex sonography has become a standard diagnostic technique to assess the intracranial arterial status in acute stroke. It is increasingly used for the evaluation of prognosis and the success of revascularization in multicenter trials. The aim of this international consensus procedure was to develop recommendations on the methodology and documentation to be used for assessment of intracranial occlusion and for monitoring of recanalization. METHODS: Thirty-five experts participated in the consensus process. The presented recommendations were approved during a meeting of the consensus group in October 2008 in Giessen, Germany. The project was an initiative of the German Competence Network Stroke and performed under the auspices of the Neurosonology Research Group of the World Federation of Neurology. RESULTS: Recommendations are given on how examinations should be performed in the time-limited situation of acute stroke, including criteria to assess the quality of the acoustic bone window, the use of echo contrast agents, and the evaluation of intracranial vessel status. The important issues of the examiners' training and experience, the documentation, and analysis of study results are addressed. One central aspect was the development of standardized criteria for diagnosis of arterial occlusion. A transcranial color-coded duplex sonography recanalization score based on objective hemodynamic criteria is introduced (consensus on grading intracranial flow obstruction [COGIF] score). CONCLUSIONS: This work presents consensus statements in an attempt to standardize the application of transcranial color-coded duplex sonography in the setting of acute stroke research, aiming to improve the reliability and reproducibility of the results of future stroke studies.

Thrombolysis in childhood stroke: report of 2 cases and review of the literature.

BACKGROUND AND PURPOSE: No controlled, randomized trial has investigated whether intravenous, intra-arterial (IAT), or mechanical thrombolysis is beneficial in children with ischemic stroke. We report 2 children who underwent IAT for acute ischemic stroke and include them in a review about intravenous thrombolysis, IAT, and mechanical thrombolysis for childhood stroke. METHODS: We searched in MEDLINE and EMBASE for studies that reported on treatment of childhood stroke with intravenous thrombolysis, IAT, or mechanical thrombolysis in the presence of occlusion of the basilar artery, sphenoidal, or insular middle cerebral artery. To be included in this review, the following findings had to be reported: (1) stroke severity at presentation; (2) cerebral imaging findings before thrombolysis; (3) time to treatment; (4) dose of the thrombolytic agent; (5) pre- and postinterventional angiographic findings in IAT; and (6) outcome assessed at hospital discharge or within 12 months after thrombolysis. RESULTS: Adequate data were available in 17 children (including our 2 own cases) who underwent intravenous thrombolysis (n=6), IAT (n=10), or mechanical thrombolysis (n=1). No symptomatic intracranial hemorrhage occurred, but 2 asymptomatic intracranial hemorrhages were present. Sixteen children (94%) survived, and 12 (71%) had a good outcome (modified Rankin Scale score 0 or 1). CONCLUSIONS: The available data about thrombolysis in pediatric stroke are limited. They suggest that this treatment may be beneficial in children with ischemic stroke. Controlled, randomized trials are needed to determine whether thrombolysis is useful in childhood stroke.

Intravenous thrombolysis in stroke attributable to cervical artery dissection.

BACKGROUND AND PURPOSE: Intravenous thrombolysis (IVT) for stroke seems to be beneficial independent of the underlying etiology. Whether this is also true for cervical artery dissection (CAD) is addressed in this study. METHODS: We used the Swiss IVT databank to compare outcome and complications of IVT-treated patients with CAD with IVT-treated patients with other etiologies (non-CAD patients). Main outcome and complication measures were favorable 3-month outcome, intracranial cerebral hemorrhage, and recurrent ischemic stroke. Modified Rankin Scale score

Increased prevalence of hyperhomocysteinemia in cervical artery dissection causing stroke: a case-control study.

BACKGROUND: Spontaneous cervical artery dissection (sCAD) is a nonatherosclerotic vascular disease of unknown etiology. Mild elevation of total plasma homocysteine (tHcy) levels may be a risk factor for sCAD, but the precise mechanism remains unknown. On the other hand, mild hyperhomocysteinemia is also associated with ischemic stroke related to atherothrombotic or small artery disease. We undertook a case-control study to compare the prevalence of mild hyperhomocysteinemia and tHcy levels between patients with a first ischemic stroke due to sCAD and healthy volunteers, as well as patients with a first ischemic stroke due to atherothrombotic or small artery disease. METHODS: Fasting tHcy levels were determined in 346 consecutive patients with a first ischemic stroke due to sCAD (n = 86) and atherothrombotic or small artery disease (n = 260) within 24 h after the onset of symptoms, and in 100 healthy volunteers. RESULTS: Mild hyperhomocysteinemia was more prevalent in patients with sCAD causing ischemic stroke (n = 33, 38%) than in healthy volunteers (n = 23, 23%; p = 0.034), and less prevalent than in patients with ischemic stroke due to atherothrombotic or small artery disease (n = 149, 57%; p = 0.001). Mean fasting tHcy levels of patients with ischemic stroke caused by sCAD showed a trend to be higher (11.4 +/- 3.8 micromol/l) than those of healthy volunteers (10.2 +/- 3.0 micromol/l, p = 0.61), but were lower than those of patients with stroke due to atherothrombotic or small artery disease (13.6 +/- 6.6 micromol/l, p = 0.002). CONCLUSION: Our results suggest that mild hyperhomocysteinemia may be a risk factor for sCAD causing ischemic stroke, but further studies are needed to identify a possible mechanism. This study confirms the association of hyperhomocysteinemia with ischemic stroke due to atherothrombotic or small artery disease.

Diffusion-weighted imaging in stroke attributable to internal carotid artery dissection: the significance of vessel patency.

BACKGROUND AND PURPOSE: In stroke attributable to spontaneous dissection of the internal carotid artery (sICAD), arterial patency may influence the pattern and extent of cerebral ischemia. METHODS: In 40 consecutive patients with stroke caused by sICAD, we compared the number, size and pattern of cerebral diffusion-weighted imaging lesions between patients with stenotic sICAD (n=15) and occlusive sICAD (n=25). RESULTS: Patients with stenotic sICAD had more ischemic lesions (median 5, interquartile range 1 to 10) than patients with occlusive sICAD (2, 1 to 3; P=0.014). Lesion diameters were larger in occlusive sICAD (62, 50 to 99 mm) than in stenotic sICAD (25, 10 to 50 mm; P=0.007). Border-zone infarction occurred only in stenotic sICAD (7/15, 47%). Most patients with occlusive sICAD had territorial infarcts (22/25, 88%). CONCLUSIONS: In stroke attributable to sICAD, diffusion-weighted imaging characteristics may be influenced by the patency of the carotid artery. Differences in the pathogenesis of cerebral ischemia might exist between patients with stenotic and those with occlusive sICAD.

Comparison of intraarterial and intravenous thrombolysis for ischemic stroke with hyperdense middle cerebral artery sign.

BACKGROUND AND PURPOSE: It is unclear whether intraarterial (IAT) or intravenous (IVT) thrombolysis is more effective for ischemic stroke with hyperdense middle cerebral artery sign (HMCAS) on computed tomography (CT). The aim of this study was to compare IAT and IVT in stroke patients with HMCAS. METHODS: Comparison of data from 2 stroke units with similar management of stroke associated with HMCAS, except that 1 unit performed IAT with urokinase and the other IVT with plasminogen activator. Time to treatment was up to 6 hours for IAT and up to 3 hours for IVT. Outcome was measured by mortality and the modified Rankin Scale (mRS), dichotomized at 3 months into favorable (mRS 0 to 2) and unfavorable (mRS 3 to 6). RESULTS: One hundred twelve patients exhibited a HMCAS, 55 of 268 patients treated with IAT and 57 of 249 patients who underwent IVT. Stroke severity at baseline and patient age were similar in both groups. Mean time to treatment was longer in the IAT group (244+/-63 minutes) than in the IVT group (156+/-21 minutes; P=0.0001). However, favorable outcome was more frequent after IAT (n=29, 53%) than after IVT (n=13, 23%; P=0.001), and mortality was lower after IAT (n=4, 7%) than after IVT (n=13, 23%; P=0.022). After multiple regression analysis IAT was associated with a more favorable outcome than IVT (P=0.003) but similar mortality (P=0.192). CONCLUSIONS: In this observational study intraarterial thrombolysis was more beneficial than IVT in the specific group of stroke patients presenting with HMCAS on CT, even though IAT was started later. Our results indicate that a randomized trial comparing both thrombolytic treatments in patients with middle cerebral artery occlusion is warranted.

Ultrasound diagnosis of spontaneous carotid dissection with isolated Horner syndrome.

BACKGROUND AND PURPOSE: Isolated Horner syndrome without associated cranial nerve palsies or ischemic symptoms is an important presentation of spontaneous internal carotid artery dissection (sICAD). Ultrasound is often used as a screening method in these patients because cervical MRI is not always available on an emergency basis. Current knowledge on ultrasound findings in patients with sICAD presenting with isolated Horner syndrome is limited. METHODS: Patients were recruited from prospective cervical artery dissection databases of 3 tertiary care centers. Diagnosis of sICAD was confirmed by cervical MRI and MR angiography or digital subtraction angiography in all patients. Data on Doppler sonography and color duplex sonography examinations performed within 30 days of symptom onset were analyzed. RESULTS: We identified 88 patients with Horner syndrome as the only sign of sICAD. Initial ultrasound examination was performed in 72 patients after a mean time interval from symptom onset to examination of 11 (SD 8) days. The overall frequency of false-negative ultrasound findings was 31% (22 of 72 patients). It showed stenosis >or=80% or occlusion in 34 (47%) patients, and stenosis