FLAIR Vascular Hyperintensities as a Surrogate of Collaterals in Acute Stroke: DWI Matters.

BACKGROUND AND PURPOSE: FLAIR vascular hyperintensities are thought to represent leptomeningeal collaterals in acute ischemic stroke. However, whether all-FLAIR vascular hyperintensities or FLAIR vascular hyperintensities-DWI mismatch, ie, FLAIR vascular hyperintensities beyond the DWI lesion, best reflects collaterals remains debated. We aimed to compare the value of FLAIR vascular hyperintensities-DWI mismatch versus all-FLAIR vascular hyperintensities for collateral assessment using PWI-derived collateral flow maps as a reference. MATERIALS AND METHODS: We retrospectively reviewed the registries of 6 large stroke centers and included all patients with acute stroke with anterior circulation large-vessel occlusion who underwent MR imaging with PWI before thrombectomy. Collateral status was graded from 1 to 4 on PWI-derived collateral flow maps and dichotomized into good (grades 3-4) and poor (grades 1-2). The extent of all-FLAIR vascular hyperintensities and FLAIR vascular hyperintensities-DWI mismatch was assessed on the 7 cortical ASPECTS regions, ranging from 0 (absence) to 7 (extensive), and associations with good collaterals were compared using receiver operating characteristic curves. RESULTS: Of the 209 included patients, 133 (64%) and 76 (36%) had good and poor collaterals, respectively. All-FLAIR vascular hyperintensity extent was similar between collateral groups (P = .76). Conversely, FLAIR vascular hyperintensities-DWI mismatch extent was significantly higher in patients with good compared with poor collaterals (P < .001). The area under the curve was 0.80 (95% CI, 0.74-0.87) for FLAIR vascular hyperintensities-DWI mismatch and 0.52 (95% CI, 0.44-0.60) for all-FLAIR vascular hyperintensities (P < .001 for the comparison), to predict good collaterals. Variables independently associated with good collaterals were smaller DWI lesion volume (P < .001) and larger FLAIR vascular hyperintensities-DWI mismatch (P = .02). CONCLUSIONS: In acute ischemic stroke with large-vessel occlusion, the extent of FLAIR vascular hyperintensities does not reliably reflect collateral status unless one accounts for DWI.

Flow Diversion in the Treatment of Intracranial Aneurysms: A Pragmatic Randomized Care Trial.

BACKGROUND AND PURPOSE: Flow diversion is a recent endovascular treatment for intracranial aneurysms. We compared the safety and efficacy of flow diversion with the alternative standard management options. MATERIALS AND METHODS: A parallel group, prerandomized, controlled, open-label pragmatic trial was conducted in 3 Canadian centers. The trial included all patients considered for flow diversion. A Web-based platform 1:1 randomly allocated patients to flow diversion or 1 of 4 alternative standard management options (coiling with/without stent placement, parent vessel occlusion, surgical clipping, or observation) as prespecified by clinical judgment. Patients ineligible for alternative standard management options were treated with flow diversion in a registry. The primary safety outcome was death or dependency (mRS > 2) at 3 months. The composite primary efficacy outcome included the core lab-determined angiographic presence of a residual aneurysm, aneurysm rupture, progressive mass effect during follow-up, or death or dependency (mRS > 2) at 3-12 months. RESULTS: Between May 2011 and November 2020, three hundred twenty-three patients were recruited: Two hundred seventy-eight patients (86%) had treatment randomly allocated (139 to flow diversion and 139 to alternative standard management options), and 45 (14%) received flow diversion in the registry. Patients in the randomized trial frequently had unruptured (83%), large (52% ≥10 mm) carotid (64%) aneurysms. Death or dependency at 3 months occurred in 16/138 patients who underwent flow diversion and 12/137 patients receiving alternative standard management options (relative risk, 1.33; 95% CI, 0.65-2.69; P = .439). A poor primary efficacy outcome was found in 30.9% (43/139) with flow diversion and 45.6% (62/136) of patients receiving alternative standard management options, with an absolute risk difference of 14.7% (95% CI, 3.3%-26.0%; relative risk, 0.68; 95% CI, 0.50-0.92; P = .014). CONCLUSIONS: For patients with mostly unruptured, large, anterior circulation (carotid) aneurysms, flow diversion was more effective than the alternative standard management option in terms of angiographic outcome.

Predictive factors of functional independence after optimal reperfusion in anterior circulation ischaemic stroke with indication for intravenous thrombolysis plus mechanical thrombectomy.

BACKGROUND AND PURPOSE: Intravenous thrombolysis plus mechanical thrombectomy (IVT + MT) is the best current management of acute stroke due to large-vessel occlusion and results in optimal reperfusion for most patients. Nevertheless, some of these patients do not subsequently achieve functional independence. The aim was to identify baseline factors associated with 3-month independence after optimal reperfusion and to validate a prediction model. METHODS: All consecutive patients with intracranial anterior large-vessel occlusion, with indication for IVT + MT and achieving optimal reperfusion (defined as modified Treatment in Cerebral Ischaemia score 2b-3), from the THRACE trial and the ETIS registry, were included in order to identify a prediction model. The primary outcome was 3-month independence [modified Rankin Scale (mRS) score ≤ 2]. Multivariate inferences invoked forward logistic regression, multiple imputation and bootstrap resampling. Predictive performance was assessed by c-statistic. Model validation was conducted on patients from the ASTER trial. RESULTS: Amongst 139 patients (mean age 65.5 years; 54.3% female), predictors of 3-month mRS ≤ 2 (n = 82) were younger age [odds ratio 0.62 per 10-year increase; 95% confidence interval (CI) 0.53-0.72] and higher Alberta Stroke Program Early Computed Tomography Score (ASPECTS) (odds ratio 1.65 per 1-point increase; 95% CI 1.47-1.86) with c-statistic 0.77. Model validation (n = 104/181 patients with 3-month mRS ≤ 2) demonstrated a moderate discrimination (c-statistic 0.74; 95% CI 0.66-0.81) combining age and ASPECTS. The validation model was improved by the adjunction of three candidate variables that were found to be predictors. Addition of baseline National Institutes of Health Stroke Scale (NIHSS) score, history of vascular risk factor and onset-to-reperfusion time significantly improved discrimination (c-statistic 0.85; 95% CI 0.83-0.87). CONCLUSIONS: After optimal reperfusion, younger age, higher ASPECTS, lower NIHSS score, shorter onset-to-reperfusion time and absence of vascular risk factor were predictive of independence and could help to guide patient management.

Clot Burden Score and Collateral Status and Their Impact on Functional Outcome in Acute Ischemic Stroke.

BACKGROUND AND PURPOSE: Collateral status and thrombus length have been independently associated with functional outcome in patients with acute ischemic stroke. It has been suggested that thrombus length would influence functional outcome via interaction with the collateral circulation. We investigated the individual and combined effects of thrombus length assessed by the clot burden score and collateral status assessed by a FLAIR vascular hyperintensity-ASPECTS rating system on functional outcome (mRS). MATERIALS AND METHODS: Patients with anterior circulation acute ischemic stroke due to large-vessel occlusion from the ASTER and THRACE trials treated with endovascular thrombectomy were pooled. The clot burden score and FLAIR vascular hyperintensity score were determined on MR imaging obtained before endovascular thrombectomy. Favorable outcome was defined as an mRS score of 0-2 at 90 days. Association of the clot burden score and the FLAIR vascular hyperintensity score with favorable outcome (individual effect and interaction) was examined using logistic regression models. RESULTS: Of the 326 patients treated by endovascular thrombectomy with both the clot burden score and FLAIR vascular hyperintensity assessment, favorable outcome was observed in 165 (51%). The rate of favorable outcome increased with clot burden score (smaller clots) and FLAIR vascular hyperintensity (better collaterals) values. The association between clot burden score and functional outcome was significantly modified by the FLAIR vascular hyperintensity score, and this association was stronger in patients with good collaterals, with an adjusted OR = 6.15 (95% CI, 1.03-36.81). CONCLUSIONS: The association between the clot burden score and functional outcome varied for different collateral scores. The FLAIR vascular hyperintensity score might be a valuable prognostic factor, especially when contrast-based vascular imaging is not available.

Functional outcome 1 year after aneurysmal subarachnoid hemorrhage due to ruptured intracranial aneurysm in elderly patients.

BACKGROUND: Population aging raises questions about extending treatment indications in elderly patients with aneurysmal subarachnoid hemorrhage (aSAH). We therefore assessed functional status 1 year after treatment. METHODS: This study involved 310 patients, aged over 70 years, with ruptured brain aneurysm, enrolled between 2008 and 2014 in a prospective multicentre trial (FASHE study: NCT00692744) but considered unsuitable for randomisation and therefore analysed in the observational arms of the study: endovascular occlusion (EV), microsurgical exclusion (MS) and conservative treatment. The aims were to assess independence, cognition, autonomy and quality of life (QOL) at 1 year post-treatment, using questionnaires (MMSE, ADLI, IADL, EORTC-QLQ-C30) filled in by independent nurses after discharge. RESULTS: The 310 patients received the following treatments: 208 underwent EV (67.1%), 54 MS (17.4%) and 48 were conservatively managed (15.5%). At 1 year, independence rates for patients admitted with good clinical status (WFNS I-III) were, according to the aneurysm exclusion procedure (EV, MS or conservative), 58.9%, 50% and 12.1% respectively. MMSE score was pathological in 26 of the 112 EV patients (23.2%), 10 of the 25 MS patients (40%) and 4 of the 9 patients treated conservatively (44%), without any statistically significant difference [Pearson's Chi2 test, F ratio=4.29; P=0.11]. Regarding QoL, overall score was similar between the EV and MS cohorts, but significantly lower with conservative treatment. CONCLUSION: Elderly patients in good clinical condition with aSAH should be treated regardless of associated comorbidities. Curative treatment (EV or MS) reduced mortality without increasing dependence, in comparison with conservative treatment.

The ophthalmic artery: a new variant involving two branches from the supracavernous internal carotid artery.

PURPOSE: We report an extremely rare, double ophthalmic artery configuration. METHODS: We present 2D- and 3D-angiographic features of an anomalous origin of the ophthalmic artery. RESULTS: The double ophthalmic artery was the result of the persistence of the primitive dorsal ophthalmic artery combined with the presence of a second orbital artery originating from the supracavernous internal carotid artery, passing through the superior orbital fissure and into the orbit to furnish the muscular, lacrimal and ethmoidal arteries and the medial long posterior ciliary artery. CONCLUSIONS: A heretofore undocumented instance of ophthalmic artery duplication is presented. Knowledge of such variations is important for the planning of endovascular treatments and the comprehension of unusual angiographic images. Such fine arterial variants may very well be frequent, but difficult to demonstrate on simple 2D angiographies. Multiplanar reconstructions of 3D angiography data make it possible to diagnose rare, but embryologically predictable arterial variants.

Susceptibility-Weighted Angiography for the Follow-Up of Brain Arteriovenous Malformations Treated with Stereotactic Radiosurgery.

The criterion standard for assessing brain AVM obliteration postradiosurgery is DSA. To explore the value of susceptibility-weighted angiography, we followed 26 patients with brain AVMs treated by radiosurgery using susceptibility-weighted angiography and DSA. Studies were evaluated by 2 independent readers for residual nidi. Susceptibility-weighted angiography demonstrated good intermodality (κ = 0.71) and interobserver (κ = 0.64) agreement, and good sensitivity (85.7%) and specificity (85.7%). Susceptibility-weighted angiography is a useful radiation- and contrast material-free technique to follow-up brain AVM obliteration postradiosurgery.

Two-Layered Susceptibility Vessel Sign and High Overestimation Ratio on MRI Are Predictive of Cardioembolic Stroke.

In a prospective study among patients in the THRombectomie des Artères Cerebrales trial, we analyzed the diagnostic accuracy of 2 imaging biomarkers, the 2-layered susceptibility vessel sign and a high overestimation ratio, obtained on pretreatment brain T2* sequences, to identify cardioembolic stroke etiology (107/260 patients). In combination, these 2 biomarkers, on 1.5T or 3T systems (159 and 101 patients, respectively), demonstrated high specificity (0.77 at 1.5T and 1 at 3T) and their simultaneous presence is highly associated with cardioembolism.

A randomized controlled study assessing outcome, cognition, autonomy and quality of life in over 70-year-old patients after aneurysmal subarachnoid hemorrhage.

BACKGROUND: Current aging of the population with good physiological status and the increasing incidence of subarachnoid hemorrhage (SAH) in elderly patients has enhanced the benefit of treatment in terms of independence and long-term quality of life (QoL). METHODS: From November 1, 2008 to October 30, 2012, 351 patients aged 70 years or older with aneurysmal SAH underwent adapted treatment: endovascular coiling (EV) for 228 (65%) patients, microsurgical clipping (MS) for 75 (29.3%) or conservative treatment for 48 (13.7%). Forty-one of these were randomized to EV (n=20) or to MS (n=21). The objectives were to determine the proportion of patients with modified Rankin Scale score≤2 (independence) at 1 year, and, secondarily, to compare cognitive function on the Mini-Mental State Examination (MMSE), autonomy on the Activities of Daily Living Index (ADLI) and Instrumental Activities of Daily Living scale (IADL), and QoL, in the prospective and randomized arms, at 1 year. RESULTS: At 1 year, with 1 loss to follow-up in the EV arm, 11 patients (55%) were independent after EV occlusion and 8 (38.1%) after MS exclusion, without significant difference (P=0.29). Mortality was higher after MS during the first 2 postoperative months, and thereafter the difference between MS and EV ceased to be significant. Cognitive function and autonomy scores were similar in both arms. CONCLUSION: In elderly patients treated for aneurysmal SAH, approximately 50% were independent at 1 year, with conserved cognition and autonomy. EV and MS are valid procedures in this population, with similar results at 1 year in terms of independence, cognition, autonomy, and QoL.

Thrombectomy outcomes for acute stroke patients with anterior circulation tandem lesions: a clinical registry and an update of a systematic review with meta-analysis.

BACKGROUND AND PURPOSE: Although mechanical thrombectomy (MT) appears to be superior in stroke patients with extracranial carotid disease (ECD) compared to thrombolysis alone, the impact of emergent carotid stenting during MT remains unclear. The MT outcomes were assessed in anterior stroke patients with ECD, especially when combined with carotid stenting. METHODS: A retrospective analysis of our registry was performed and an update of a systematic review and meta-analysis of MT studies with or without stenting for anterior circulation stroke with ECD published between November 2010 and April 2017 was conducted. RESULTS: In our registry, 46 patients with ECD underwent MT. In the meta-analysis including 13 primary studies plus our prospective registry data (590 patients in total), the successful reperfusion rate (modified thrombolysis in cerebral infarction score ≥2b) reached 75% [95% confidence interval (CI) 69%-81%]. The rate of symptomatic intracranial haemorrhage (sICH) was 8% (95% CI 6%-11%), 90-day favourable outcome was achieved in 50% (95% CI 42%-59%) and mortality rate was 16% (95% CI 11%-22%). When using carotid stenting, rates of successful reperfusion, sICH, 90-day favourable outcome and mortality were 80% (95% CI 73%-87%), 7% (95% CI 4%-12%), 53% (95% CI 43%-62%) and 14% (95% CI 9%-19%), respectively. CONCLUSIONS: Our data report an association between acute stenting and successful reperfusion rates in stroke patients with tandem lesion treated with MT. Further studies are warranted to determine the intracranial bleeding risk after MT and stenting according to the antiplatelet therapy.

Hydrogel versus Bare Platinum Coils in Patients with Large or Recurrent Aneurysms Prone to Recurrence after Endovascular Treatment: A Randomized Controlled Trial.

BACKGROUND AND PURPOSE: Some patients are at high risk of aneurysm recurrence after endovascular treatment: patients with large aneurysms (Patients Prone to Recurrence After Endovascular Treatment PRET-1) or with aneurysms that have previously recurred after coiling (PRET-2). We aimed to establish whether the use of hydrogel coils improved efficacy outcomes compared with bare platinum coils. MATERIALS AND METHODS: PRET was an investigator-led, pragmatic, multicenter, parallel, randomized (1:1) trial. Randomized allocation was performed separately for patients in PRET-1 and PRET-2, by using a Web-based platform ensuring concealed allocation. The primary outcome was a composite of a residual/recurrent aneurysm, adjudicated by a blinded core laboratory, or retreatment, intracranial bleeding, or mass effect during the 18-month follow-up. Secondary outcomes included adverse events, mortality, and morbidity (mRS > 2). The hypothesis was that hydrogel would decrease the primary outcome from 50% to 30% at 18 months, necessitating 125 patients per group (500 for PRET-1 and PRET-2). RESULTS: The trial was stopped once 250 patients in PRET-1 and 197 in PRET-2 had been recruited because of slow accrual. A poor primary outcome occurred in 44.4% (95% CI, 35.5%-53.2%) of those in PRET-1 allocated to platinum compared with 52.5% (95% CI, 43.4%-61.6%) of patients allocated to hydrogel (OR, 1.387; 95% CI, 0.838-2.295; P = .20) and in 49.0% (95% CI, 38.8%-59.1%) in PRET-2 allocated to platinum compared with 42.1% (95% CI, 32.0%-52.2%) allocated to hydrogel (OR, 0.959; 95% CI, 0.428-1.342; P = .34). Adverse events and morbidity were similar. There were 3.6% deaths (1.4% platinum, 5.9% hydrogel; P = .011). CONCLUSIONS: Coiling of large and recurrent aneurysms is safe but often poorly effective according to angiographic results. Hydrogel coiling was not shown to be better than platinum.

[Endovascular treatment of giant intracranial aneurysms]. / Traitement endovasculaire des anévrismes géants.

Giant aneurysms are defined as having a maximal diameter higher than 25mm. The dynamic aspect of giant aneurysms, in particular, is its growth, which was responsible for parenchyma sequellae either due to haemorrhagic complications or a compression of cranial nerves. The treatment of these giant aneurysms was challenging because of its size, the mass effect and the neck diameter. These morphologic conditions required complex endovascular procedures such as remodelling, stenting, using flow diverters. Subsequently, the complex procedures increased the risk of morbidity because of ischemic complications. Despite these procedures, the risk of recurrence was high.

Endovascular treatment of ruptured intracranial aneurysms: Indications, techniques and results.

Rupture of an intracranial aneurysm is a diagnostic and therapeutic emergency. Occlusion of the aneurysm with coils is the first line treatment and should be performed promptly to avoid any further rupture, which carries a poor prognosis. Most aneurysms are accessible to this type of treatment. The risks of coiling, which are mostly thromboembolic and less commonly hemorrhagic due to peroperative rupture, are low. The use of stents or a flow diverter requires dual anti-aggregation which increases their risks so that their use are restricted to specific situations such as dissecting aneurysms. Endovascular treatment is effective in the long and short term prevention of recurrent hemorrhage provided that patients are followed up by imaging, which allows possible early recanalization to be detected early and treated if necessary.

Subtentorial cerebral nocardiosis in immunocompetent patients: CT and MR imaging findings.

PURPOSE: To describe the clinical presentation and computed tomography (CT) and magnetic resonance imaging (MRI) appearances of subtentorial nocardia cerebral abscesses developing in immunocompetent patients. PATIENTS AND METHODS: The clinical findings and the results of CT and MRI examinations of three immunocompetent patients with nocardiosis located initially only in the subtentorial region were studied. Three patients underwent CT examination and two patients had MRI. RESULTS: Clinically, two patients had cerebellar syndrome and the third had meningism with fever. The diagnosis of nocardiosis was bacteriologically confirmed by demonstrating the organism in lumbar puncture fluid in one patient and by an aspiration biopsy of the abscess in the other two. Two of the patients improved under targeted antibiotic therapy whereas the third patient died. The main imaging features of the lesions were a multiloculated appearance with peripheral enhancement after intravenous administration of iodinated contrast material on CT and a multicystic appearance on MRI, with a peripheral hypointense rim on T2-weighted images, a relatively minor mass effect and a multiloculated appearance on gadolinium-chelate enhanced T1-weighted images. CONCLUSION: The clinical presentation of cerebral nocardiosis is relatively non-specific. A microcystic lesion surrounded by hypointensity on T2-weighted MR images with a multiloculated pattern after gadolinium chelate administration on T1-weighted MR images in association with a relatively minor mass effect should suggest this diagnosis even if the lesion is single and in the absence of immunosuppression.

Patients prone to recurrence after endovascular treatment: periprocedural results of the PRET randomized trial on large and recurrent aneurysms.

BACKGROUND AND PURPOSE: Some patients with large or recurrent aneurysms may be at increased risk of recurrence postcoiling. The Patients Prone to Recurrence after Endovascular Treatment (PRET) trial was designed to assess whether hydrogel coils were superior to platinum coils in these high-risk patients. This article reports periprocedural safety and operator-assessed angiographic results from the PRET trial. MATERIALS AND METHODS: PRET was a pragmatic, multicenter, randomized controlled trial. Patients had ≥10-mm aneurysms (PRET-1) or a major recurrence after coiling of an aneurysm of any size (PRET-2). Patients were randomly allocated to hydrogel or control arms (any platinum coil) by using concealed allocation with minimization. Assist devices could be used as clinically required. Aneurysms could be unruptured or recently ruptured. Analyses were on an intent-to-treat basis. RESULTS: Four hundred forty-seven patients were recruited (250 PRET-1; 197 PRET-2). Aneurysms were recently ruptured in 29% of PRET-1 and 4% of PRET-2 patients. Aneurysms were ≥10 mm in all PRET-1 and in 50% of PRET-2 patients. They were wide-neck (≥4 mm) in 70% and in the posterior circulation in 24% of patients. Stents were used in 28% of patients (35% in PRET-2). Coiling was successful in 98%. Adverse events occurred in 28 patients with hydrogel and 23 with platinum coils. Mortality (n=2, unrelated to treatment) and morbidity (defined as mRS>2 at 1 month) occurred in 25 patients (5.6%; 12 hydrogel, 13 platinum), related to treatment in 10 (4 hydrogel; 6 platinum) (or 2.3% of 444 treated patients). No difference was seen between hydrogel and platinum for any of the indices used to assess safety up to at least 30 days after treatment. At 1 month, 95% of patients were home with a good outcome (mRS≤2 or unchanged). Operator-assessed angiographic outcomes were satisfactory (complete occlusion or residual neck) in 339 of 447 or 76.4% of patients, with no significant difference between groups. CONCLUSIONS: Endovascular treatment of large and recurrent aneurysms can be performed safely with platinum or hydrogel coils.

Endovascular treatment of aneurisms: pre, intra and post operative management.

The most frequent risk in endovascular aneurysm treatment is thromboembolic complications. Thus adjuvant pharmaceuticals are largely focused on preventing and treating these latter. Additionally symptomatic treatment of subarachnoid hemorrhage (SAH) and treatments to avoid vasospasm will enter into play in cases of ruptured aneurisms. Consensus exists in the literature neither for the necessity of heparin or antiplatelets nor for the doses to be administered. The principles and rationale of the use of these medications are reviewed with a discussion of protocols according with clinical situations and technical choices.

[Treatment of arterial and venous brain ischemia. Experts' recommendations: stroke management in the intensive care unit]. / Traitement de l'ischémie cérébrale artérielle et veineuse. Recommandations formalisées d'experts: Prise en charge de l'AVC par le réanimateur.

With thrombolysis, intravenous alteplase (0.9 mg/kg body weight, maximum 90 mg), with 10% of the dose given as a bolus followed by a 60-minute infusion, is recommended within 4.5 hours of onset of ischemic stroke. When indicated, intravenous thrombolysis must be initiated as soon as possible. It is possible to use intravenous alteplase in patients with seizures at stroke onset, if the neurological deficit is related to acute cerebral ischemia. Intravenous alteplase can be discussed for use on a case-by-case basis, according to risk of bleeding, in selected patients under 18 years and over 80 years of age, although for the current European recommendations this would be an off-label use. In hospitals with a stroke unit, intravenous thrombolysis is prescribed by a neurologist (current French labelling) or a physician having the French certification for neurovascular diseases (outside the current French labelling). The patient must be monitored in the stroke unit or in case of multiple organ failure in an intensive and critical care unit. In hospitals without a stroke unit, thrombolysis must be decided by the neurologist from the corresponding stroke unit via telemedicine. It is recommended to perform brain imaging 24 hours after thromboysis. Intra-arterial thrombolysis can be contemplated on a case-by-case basis after multidisciplinary discussion within a 6-hour time window for patients with acute middle cerebral artery or carotid occlusions, and within a larger time window for patients with basilar artery occlusion, because of their very poor spontaneous prognosis. Mechanical thrombectomy can also be contemplated in the same situations. With antiplatelet agents, it is recommended that patients receive aspirin (160 mg-325 mg) within 48 hours of ischemic stroke onset. When thrombolysis is performed or contemplated, it is recommended to delay the initiation of aspirin or other antithrombotic drugs for 24 hours. The use of antiplatelet agents that inhibit the glycoprotein IIb/IIIa receptor is not recommended. Urgent anticoagulation using heparin, low-molecular-weight heparins or danaparoid with the goal to treat ischemic stroke patients is not recommended. Secondary prevention by anticoagulation can be used, immediately or within the first days, after minor ischemic stroke or TIA in patients with a high risk for cardioembolism, if uncontrolled hypertension is absent. In patients with large infarcts and a high risk for cardioembolism, the timing for initiating anticoagulation must be decided on a case-by-case basis. In patients with anticoagulation who had an ischemic stroke, the decision to temporarily stop or maintain anticoagulation must be made on a case-by-case basis, depending on thromboembolic risk, level of anticoagulation at stroke onset and estimated risk of hemorrhagic transformation. It is not recommended to use neuroprotective agents in ischemic stroke patients. Patients with cerebral venous thrombosis must be treated with therapeutic doses of heparin, even in case of concomitant intracranial hemorrhage related to cerebral venous thrombosis. If the patient's status worsens despite adequate anticoagulation, thrombolysis may be used in selected cases. The optimal administration route (local or intravenous), thrombolytic agent (urokinase or alteplase) and dose are unknown. There is currently no recommendation with regard to local thrombolytic therapy in patients with dural sinus thrombosis. Urgent blood transfusions are recommended to reduce hemoglobin S to <30% in patients with sickle cell disease and acute ischemic stroke.

Prevalence of MRI-defined recent silent ischemia and associated bleeding risk with thrombolysis.

BACKGROUND: Uncertainties about the frequency and the associated bleeding risk of recent silent ischemia (RSI), incidentally found on pretreatment MRI, in candidates for thrombolysis require clarification because exclusion from therapy is a serious consequence for patients with such MRI findings. METHODS: We retrospectively analyzed the fluid-attenuated inversion recovery (FLAIR)/diffusion-weighted imaging (DWI) obtained before IV thrombolysis in 115 patients to search for MRI-defined RSI; these corresponded to well-developed FLAIR/DWI brain hyperintensities (RSI+), as distinct from the acute index ischemia, which typically lacked FLAIR changes. Patients without such findings were assigned to the RSI- group. Groups were compared for baseline characteristics and for rates of symptomatic and asymptomatic hemorrhagic transformation (HT) using odds ratios (OR) and their 95%confidence intervals (CI). RESULTS: We observed RSI in 21 patients (18.3%). The mean (SD) volume of RSI was 6.5 (12) mL (interquartile range 0.6-9). None of the baseline parameters differed between groups. There was no significant difference in rates of any type of HT between groups. Parenchymal hemorrhage type 1 or type 2 according to European Cooperative Acute Stroke Study criteria occurred in 2 (10%) RSI+ patients and in 10 (11%) RSI- patients (OR 0.88; 95% CI 0.18-4.37). Symptomatic HT, defined according to National Institute of Neurological Disorders and Stroke criteria, occurred in 1 (5%) RSI+ patient and in 10 (11%) RSI- patients (OR 0.42; 95% CI 0.05-3.47). CONCLUSIONS: We found that 18.3% of patients with acute stroke treated by IV thrombolysis in a stroke unit had RSI on pretreatment MRI. However, the presence of RSI was not associated with an increased risk of asymptomatic or symptomatic HT.

[Imaging of cranial gunshot traumas]. / Imagerie des traumatismes crâniens par arme à feu.

Cranial traumas from gunshot wounds are characterised by the impact of a high velocity projectile. There are therefore serious, life threatening traumas. CT Scan is essential in the emergency setting for initial evaluation of traumatic bone and parenchymatous injuries to determine the indication for neurosurgery and appropriate medical management. In case of survival, CT Scan and MRI can be used to monitor progress and any possible complications, in particular vascular or infectious complications which are specific to this type of injury.

Dynamic susceptibility contrast-enhanced MRI evaluation of cerebral intraventricular tumors: preliminary results.

INTRODUCTION: The aims of the present study were to determine the perfusion characteristics of several types of intraventricular tumors and to evaluate the usefulness of dynamic contrast-enhanced MRI in making the differential diagnosis. METHODS: A total of 28 patients with intraventricular tumors (five meningiomas, five papillomas, three ependymomas, four subependymomas, seven central neurocytomas, two subependymal giant cell astrocytomas and two metastases) underwent conventional and dynamic susceptibility contrast-enhanced MRI. Cerebral blood volume (CBV) maps were obtained and the relative CBV (rCBV) calculated for each tumor. Mean rCBV(max) values were compared across the different types of tumors (ANOVA, P=0.05). RESULTS: Intraventricular tumors presented with three different patterns of vascularization: highly vascularized tumors (mean rCBV(max)>3), including papillomas, meningiomas and renal carcinoma metastases; poorly vascularized tumors (mean rCBV(max)<2), including ependymomas and subependymomas; and intermediately vascularized tumors (mean rCBV(max)>2 but<3), including central neurocytomas and lung metastases. There was a significant difference between the highly vascularized (papillomas, meningiomas) and poorly vascularized (subependymomas) tumors. In cases of suspected meningioma, papilloma or neurocytoma, low rCBV values (<3) point to a diagnosis of neurocytoma rather than either of the other tumor types. CONCLUSION: Susceptibility contrast-enhanced MRI can provide additional information on the vascularization of intraventricular cerebral tumors and may help in making the differential diagnosis.