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Two score families were introduced to help clinicians about the decision-making regarding intracranial aneurysms management. The first family estimates the growth/rupture risk (GRS), whereas the second provides straightforward recommendation (RS) for treatment decisions. However, both remain poorly validated and little is known about their agreement. In this paper, we performed a retrospective concordance analysis among the two scores families through their application to a multicenter cohort of SAH patients.Demographical, clinical and radiological data were extracted in conformance with the variables included in PHASES, UCAS, ELAPSS, Juvela's growth score (JGS), UIATS and Juvela's treatment score (JTS). Individual patients' score were calculated for both score families, and pooled data were then analyzed.Overall, 146 patients were included. True positive rates were: 51.4% for PHASES; 71.9% for UCAS; between 60.3% and 90.4% for JTS; and between 27.4% and 68.5% for UIATS. In patients showing UIATS unclear recommendation and low JTS score (RS), UCAS outperformed PHASES (GRS) in identifying aneurysms at higher risk of rupture. Same results we found for patients with conservative UIATS recommendation and very low JTS score. Forty-to-sixty percent of aneurysms with unclear or conservative RS recommendation would have been identified as at high risk with GRS.Retrospectively applied, JTS appeared outperforming UIATS in correctly recommending treatment in a higher percentage of patients. UIATS and JTS appeared agreeing more with UCAS than PHASES predictions. Around 50% of patients with unclear or conservative UIATS/JTS recommendations were been classified as at higher growth risk by ELAPSS and JGS.

BackgroundThe purpose of this study was to evaluate the effectiveness of mechanical thrombectomy (MT) in patients with isolated M2 occlusion and minor symptoms and identify possible baseline predictors of clinical outcome.MethodsThe databases of 16 high-volume stroke centers were retrospectively screened for consecutive patients with isolated M2 occlusion and a baseline National Institutes of Health Stroke Scale (NIHSS) score ≤5 who received either early MT (eMT) or best medical management (BMM) with the possibility of rescue MT (rMT) on early neurological worsening. Because our patients were not randomized, we used propensity score matching (PSM) to estimate the treatment effect of eMT compared with the BMM/rMT. The primary clinical outcome measure was a 90-day modified Rankin Scale score of 0–1.Results388 patients were initially selected and, after PSM, 100 pairs of patients receiving eMT or BMM/rMT were available for analysis. We found no significant differences in clinical outcome and in safety measures between patients receiving eMT or BMM/rMT. Similar results were also observed after comparison between eMT and rMT. Concerning baseline predicting factors of outcome, the involvement of the M2 inferior branch was associated with a favorable outcome.ConclusionOur multicenter retrospective analysis has shown no benefit of eMT in minor stroke patients with isolated M2 occlusion over a more conservative therapeutic approach. Although our results must be viewed with caution, in these patients it appears reasonable to consider BMM as the first option and rMT in the presence of early neurological deterioration.

Introduction: We sought to verify the predicting role of a favorable profile on computed tomography perfusion (CTP) in the outcome of patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO) undergoing effective mechanical thrombectomy (MT). Methods: We retrospectively enrolled 25 patients with AIS due to LVO and with a CTP study showing the presence of ischemic penumbra who underwent effective MT, regardless of the time of onset. The controls were 25 AIS patients with overlapping demographics and clinical and computed tomography angiography features at admission who had undergone successful MT within 6 h from onset and without a previous CTP study. The outcome measure was the modified Rankin Scale (mRS) score at 90 days. Results: Sixty-four percent of the study patients had an mRS score of 0–1 at 90 days versus 12% of the control patients (p < 0.001). Patients of the study group had a more favorable distribution of disability scores (median mRS [IQR] score of 0 [0–2] vs. 2 [2–3]). Multivariate analysis showed that the selection of patients based on a favorable CTP study was strongly associated (p < 0.001) with a better neurological outcome. Conclusions: In our small-sized and retrospective study, the presence of ischemic penumbra was associated with a better clinical outcome in patients with AIS due to LVO after MT. In the future, a larger and controlled study with similar criteria of enrollment is needed to further validate the role of CTP in patient selection for MT, regardless of the time from the onset of symptoms.

Background Postinfectious Moyamoya syndrome (MMS) is a rare vasculopathy that can follow meningitis. Only 9 cases of MMS after meningitis have been reported in the literature. We present a unique case of MMS after meningitis caused by Aspergillus fumigatus and Escherichia coli and review all cases of MMS postmeningitis in the literature. Case Description A 41-year-old man was admitted to our emergency department for sudden hypoesthesia in the left arm and an intense headache not responsive to drugs. Computed tomography scan and magnetic resonance imaging showed acute ischemic lesions in the right centrum semiovale associated with bilateral chronic watershed cerebral ischemic lesions. The cerebral digital subtraction angiography documented a typical Moyamoya pattern. In anamnesis, the patient suffered from meningitis caused by A. fumigatus and E. coli infection after neurosurgery for subependymoma of the fourth ventricle 2 years before. Laboratory tests, clinical investigation, and imaging ruled out any other cause of vasculopathy and led to the final diagnosis of postinfectious MMS. The patient started medical therapy with oral acetyl salicylic acid, verapamil, and prednisone while surgical approach was excluded in the first instance. Conclusions Physicians should be aware of an uncommon but severe complication of meningitis such as MMS, even several years after the infection. Neuroimaging is essential for the diagnosis and to exclude other causes of neurologic symptoms in these patients.

Purpose Endovascular treatment represents the first-line therapy for cavernous sinus dural arteriovenous fistulas (CS-dAVF); however, different approaches and embolic agents as well as occlusion rates, complications and clinical outcomes are reported among the published series. In this study we performed a comprehensive meta-analysis to investigate clinical and radiological outcomes after endovascular treatment of CS-dAVFs. Methods PubMed, Ovid Medline, Ovid EMBASE, Scopus, and Web of Science were screened for a comprehensive literature review from 1990 to 2020 regarding series of patients treated for CS-dAVF with endovascular approaches. We performed a proportion meta-analysis estimating the pooled rates of each outcome also including data of patients treated in our center. Results A total of 22 studies reporting 1043 patients and 1066 procedures were included. Chemosis was reported in 559 out of 1043 patients (45.9%), proptosis in 498 (41.5%), and ophthalmoplegia in 344 (23.5%). A transvenous embolization was preferred in 753 cases (63.2%) and coils were used in 712 out of 1066 procedures (57.8%). Overall, 85% (95% confidence interval, CI 69.5–96.1%) of patients had a complete resolution of symptoms, while complications occurred in 7.75% (95% CI 3.82–12.7%) with minimal permanent deficits (0.15%). The mortality rate was 1 out of 1043 patients ( Conclusion A transvenous coiling is the most common endovascular approach for CS-dAVF, achieving a high percentage of radiological and clinical resolution and low complication rates. Transvenous approaches show less complications than transarterial ones, and coils appear safer than liquid embolic agents.

BackgroundPatients with minor stroke and M2 occlusion undergoing best medical management (BMM) may face early neurological deterioration (END) that can lead to poor long-term outcome. In case of END, rescue mechanical thrombectomy (rMT) seems beneficial. Our study aimed to define factors relevant to clinical outcome in patients undergoing BMM with the possibility of rMT on END, and find predictors of END.MethodsPatients with M2 occlusion and a baseline National Institutes of Health Stroke Scale (NIHSS) score≤5 that received either BMM only or rMT on END after BMM were extracted from the databases of 16 comprehensive stroke centers. Clinical outcome measures were a 90-day modified Rankin Scale (mRS) score of 0–1 or 0–2, and occurrence of END.ResultsAmong 10 169 consecutive patients with large vessel occlusion admitted between 2016 and 2021, 208 patients were available for analysis. END was reported in 87 patients that were therefore all subjected to rMT. In a logistic regression model, END (OR 3.386, 95% CI 1.428 to 8.032), baseline NIHSS score (OR 1.362, 95% CI 1.004 to 1.848) and a pre-event mRS score=1 (OR 3.226, 95% CI 1.229 to 8.465) were associated with unfavorable outcome. In patients with END, successful rMT was associated with favorable outcome (OR 4.549, 95% CI 1.098 to 18.851). Among baseline clinical and neuroradiological features, presence of atrial fibrillation was a predictor of END (OR 3.547, 95% CI 1.014 to 12.406).ConclusionPatients with minor stroke due to M2 occlusion and atrial fibrillation should be closely monitored for possible worsening during BMM and, in this case, promptly considered for rMT.

To evaluate whether arterial and venous color-coded mCTA score may predict clinical outcome in anterior circulation acute ischemic stroke.Consecutive patients referred to the emergency department with anterior circulation acute ischemic stroke (AIS) were retrospectively reviewed at our center. All patients underwent multimodal brain computed tomography (CT) imaging, including non-contrast CT (NCCT) and multiphase computed tomography angiography (mCTA). Baseline collateral scores of color-coded mCTA, also known as ColorViz, and conventional mCTA were recorded. mCTA was assessed by a 6-point scale whereas color-coded mCTA was assessed by a 3-point scale. In the Color-coded maps, a different color is assigned to intracranial vessels based on the arrival time of the contrast medium and on a per-person adaptive threshold technique. We compared the radiological and clinical features of a group of patients who reached independency (defined as modified Rankin Scale score ≤ 2) with those of patients who did not. A multivariate logistic regression model was then used to assess the potential of color-coded mCTA scores to predict patients' outcome after AIS.A total of 86 patients (36 M, 50 F) were enrolled in the study. Multivariate logistic regression showed that score 3 at Color-coded mCTA was a good predictor of favorable outcome (p = 0.003). Moreover, NIHSS at onset (p = 0.004) and discharge (p 0.001) along with ischemic core area (p = 0.011) were significant predictors of favorable prognosis.our data confirm that ColorViz is a useful and easily understandable neuroimaging tool that might have a predictive role in assessing the outcome of anterior circulation acute ischemic stroke patients regardless of revascularization therapy.

Background Recent trials established the efficacy of mechanical stent-retriever thrombectomy for treatment of stroke patients with large vessel occlusion (LVO) in the anterior circulation. However, stent-retriever thrombectomy may not accomplish successful recanalization in all patients. The aim of this study is to report the role of bail-out permanent stenting after failure of mechanical thrombectomy. Methods Among 430 patients included in a prospectively maintained database, we analysed 325 cases of anterior circulation LVO. Mechanical thrombectomy (mTICI 2b-3) was effective in 213/325 (65%) and failed in 112/325 (35%). Bail-out intracranial stenting was performed in 17/325 (5.2%) patients. In all cases a fully retrievable detachable stent was used (Solitaire AB, Medtronic). Results No intraprocedural technical complications occurred. Successful reperfusion (mTICI 2b/3) was achieved in 12/17 patients (70.6%). Three (17.6%) patients died: one extensive infarction in the internal carotid artery territory, one large intracerebral haemorrhage, and one massive pulmonary embolism. Haemorrhagic conversion, both symptomatic and asymptomatic, occurred in 2/17 (11.7%). Good clinical outcome (mRS 0–2) at 3-months was achieved in 41.2% of patients. Conclusion Bail-out intracranial stenting after unsuccessful thrombectomy is technically feasible and the associated haemorrhagic risk seems acceptable in selected patients. We suggest that bail-out intracranial stenting, is safe and effective in selected patients with LVO stroke who failed to respond to thrombectomy.

BACKGROUND AND PURPOSE: Successful vessel recanalization in posterior circulation large-vessel occlusion is considered crucial, though the evidence of clinical usefulness, compared with the anterior circulation, is not still determined. The aim of this study was to evaluate predictors of favorable clinical outcome and to analyze the effect of first-pass thrombectomy. MATERIALS AND METHODS: A retrospective, multicenter, observational study was conducted in 10 high-volume stroke centers in Europe, including the period from January 2016 to July 2019. Only patients with an acute basilar artery occlusion or a single, dominant vertebral artery occlusion (“functional” basilar artery occlusion) who had a 3-month mRS were included. Clinical, procedural, and radiologic data were evaluated, and the association between these parameters and both the functional outcome and the first-pass effect was assessed. RESULTS: A total of 191 patients were included. A lower baseline NIHSS score (adjusted OR, 0.77; 95% CI, 0.61–0.96; P = .025) and higher baseline MR imaging posterior circulation ASPECTS (adjusted OR, 3.01; 95% CI, 1.03–8.76; P = .043) were predictors of better outcomes. The use of large-bore catheters (adjusted OR, 2.25; 95% CI, 1.08–4.67; P = .030) was a positive predictor of successful reperfusion at first-pass, while the use of a combined technique was a negative predictor (adjusted OR, 0.26; 95% CI, 0.09–0.76; P = .014). CONCLUSIONS: The analysis of our retrospective series demonstrates that a lower baseline NIHSS score and a higher MR imaging posterior circulation ASPECTS were predictors of good clinical outcome. The use of large-bore catheters was a positive predictor of first-pass modified TICI 2b/3; the use of a combined technique was a negative predictor.

The benefit of mechanical thrombectomy (MT) in patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO) and baseline mild neurological symptoms remains unclear. The purpose of this study was to evaluate the effectiveness of MT in this subgroup of patients. The databases of 9 high-volume Italian stroke centers were retrospectively screened for patients with LVO in the anterior circulation and a baseline National Institute of Health Stroke Scale (NIHSS) score ≤ 5 that received either immediate MT or best medical management (BMM) with the possibility of rescue MT upon neurological worsening. Primary outcome measure was a modified Rankin Scale score of 0–1 at 90 days. Propensity score matching (PSM) analysis was used to estimate the treatment effect of immediate MT compared to BMM/rescue MT. Two hundred and seventy-two patients received immediate MT (MT group). The BMM/rescue MT group included 41 patients. The primary outcome was achieved in 78.6% (n = 246) of overall patients, with a higher proportion in the MT group (80.5% vs. 65.9%, p = 0.03) in unadjusted analysis. After PSM, patients in the MT group had a 19.5% higher chance of excellent outcome at 90 days compared to the BMM/Rescue MT group with a similar risk of death from any cause. Our experience is in favor of a potential benefit of MT also in patients with LVO and a NIHSS score ≤ 5 at the time of groin puncture. Nonetheless, this issue waits for a clear-cut recommendation in a dedicated clinical trial.

Background Decisions to treat unruptured intracranial aneurysms remain challenging, as the risk of rupture needs to be balanced with risk of intervention. In 2015, the Unruptured Intracranial Aneurysm Treatment Score (UIATS) was introduced to assist physicians in the decision making process. As its reliability is still debated, we retrospectively applied UIATS to a multicenter cohort of aneurysmal subarachnoid hemorrhage patients to test its performance in suggesting treatment in patients with known natural history. Methods Demographical, clinical, and radiological data of subarachnoid patients admitted in 2 referral cerebrovascular centers were collected. UIATS was individually calculated for each patient, and resulting recommendations were pooled in 3 groups (favor treatment, favor conservative management, unclear indication). Results One-hundred and forty-six patients were included in this study. In the event of aneurysm discovery previous to their rupture, UIATS calculation revealed that 40 (27.4%) patients would have received an indication-to-treat advice (mean score: 4.58 ± 1.32), 46 (31.5%) would have been suggested a conservative management (mean score: −7.07 ± 4.15), and 60 (41.1%) would have been included in an unclear recommendation group (mean score: 0.07 ± 1.42). UIATS sensitivity ranged between 27% and 68% depending on the inclusion of patients with unclear indication within the conservative or intervention group. Conclusions In our study, UIATS would have failed to provide a clear recommendation to treat in up to 72.6% of patients whose aneurysm eventually ruptured. In agreement with previous reports, we provide additional evidence that some unruptured intracranial aneurysms may elude UIATS sensitivity. Further long-term prospective studies are necessary to assess UIATS reliability in real-world clinical practice.

While the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) spreads all over the world, the healthcare systems are facing the dramatic challenge of simultaneously fight against the outbreak and life-threating emergencies. In this biological setting, emergency departments and neurovascular teams are exposed to high risk of infection and should therefore be prepared to deal with neurological emergencies safely. The purpose of this article is to analyze the current evidence on COVID-19 in the context of acute ischemic stroke and to describe the model of behavior we are putting into action to maintain the stroke pathway both rapid for the patient and safe for the healthcare professionals. We reserve a specific focus on personal protection equipment, dress code and healthcare professional behavior.

As the incidental diagnosis of unruptured intracranial aneurysms has been increasing, several scores were developed to predict risk of rupture and growth to guide the management choice. We retrospectively applied these scores to a multicenter series of patients with subarachnoid hemorrhage to test whether they would have predicted the risk of bleeding in the event of aneurysm discovery previous to its rupture. Demographical, clinical, and radiological information of 245 adults were retrieved from two neurovascular centers’ database. Data were pooled and PHASES, UCAS, and ELAPSS scores were retrospectively calculated for the whole population and their performances in identifying aneurysms at risk of rupture were compared. Mean PHASES, UCAS, and ELAPSS scores were 5.12 ± 3.08, 5.09 ± 2.62, and 15.88 ± 8.07, respectively. Around half (46%) of patients would have been assigned to the low- or very low-risk class (5-year rupture risk

To compare three commonly used large-bore aspiration catheters in terms of final successful recanalization rate and first-passage successful and complete recanalization rates (the so called "first-passage effect").it is an observational retrospective multicenter study conducted in three Italian high-volume tertiary stroke centers between January 2017 and May 2019. The study population included all consecutive patients with an ischemic stroke due to middle cerebral artery occlusion (M1 segment only) that underwent intra-arterial mechanical thrombectomy with contact aspiration as first-line strategy within 24 hours from symptoms onset.Three hundred twenty-one patients were included in the study. Multivariable logistic regression analysis comparing the three catheters revealed no differences in terms of successful recanalization. Sofia 6 Plus catheter was associated with better first-passage successful recanalization [OR, 9.09; 95% CI, 2.66-31.03] (p0.001) and first-passage complete recanalization [OR: 3.73; 95% CI: 1.43-9.72] (p=0.007) whereas rt-PA was associated with worse first-passage recanalization [OR: 0.52; 95% CI: 0.29-0.93] (p=0.028).No differences between the three catheters were reported in terms of successful recanalization. Sofia 6 Plus has proven to be superior in achieving both successful and complete first-passage recanalization. Conversely, rt-PA was found to be a negative predicting factor of first-passage effect.

Clot features along with patients' clinical features may influence thrombus compactness predisposing at distal embolization during thrombectomy. The aim of this study was to evaluate thrombus features assessed by radiological and histopathological analysis along with patient-related features to predict distal embolization during thrombectomy.We performed a retrospective analysis of a prospectively maintained dataset of a tertiary stroke center inclusive of all cases of endovascular treatment for acute ischemic stroke involving anterior circulation occlusion. All patients underwent head and neck CT-angiography (CTA) at baseline. Patients were enrolled if thrombus material was suitable for histopathologic analyses.A total of 327 patients underwent mechanical thrombectomy between March 2017 and May 2020. Among them, 133 (40.7%) had thrombus material suitable for histopathological analysis but 11 patients were excluded due to posterior circulation occlusion. A total of 122 patients were included in the analysis. A distal embolism was documented in 27 patients (28.4%). Multivariable analysis with distal embolism as dependent variable showed an adjusted OR of 2.64 (95%CI: 0.9-7.73; p-value: 0.08) for anticoagulant therapy, an adjusted OR of 1.38 (95%CI: 1.01-1.91; p-value 0.05) each 5-mm increasing of thrombus length at CTA. No association was found with age, sex, thrombolysis and first thrombectomy technique used.The combined effect of anticoagulant therapy and thrombus length may have a potentially harmful effect on reperfusion during mechanical recanalization, causing distal embolization and this aspect should be taken into account in patient's risk assessment and when planning treatment strategy.

Background PulseRider (Pulsar Vascular, Los Gatos, California, USA) is a new endovascular device designed to treat wide-neck bifurcation intracranial aneurysms. Deployment of a stent through a PulseRider to treat an aneurysm's recurrence has never been described before. Case Description We report the case of a 55-year-old man who underwent coiling of an 8-mm anterior communicating artery aneurysm with assistance of a PulseRider neck reconstruction device. The 6-month digital subtraction angiography control showed aneurysm recurrence, so we deployed an Enterprise 2 closed-cell stent (Codman, Miami Lakes, Florida, USA) in the A1-A2 segment passing across the previously implanted PulseRider. Enterprise correctly expanded and allowed for adequate coiling of the aneurysm. Conclusion An Enterprise stent can be safely opened through a PulseRider in order to treat aneurysm recurrence.

BACKGROUND Y-stenting is an effective but challenging approach for wide-neck aneurysms. PulseRider (PR) (Pulsar/Cerenovus) is a new device designed to provide scaffolding during coiling but has never been compared with other techniques. OBJECTIVE To compare the immediate and 6-mo results of Y-stenting vs PR assisted coiling. METHODS A total of 105 consecutive patients were retrospectively divided into 2 groups (73 Y-stenting and 32 PR). All underwent angiographic 6-mo follow-up. We evaluated if some anatomical features could influence treatment results. RESULTS The groups were homogeneous. Immediate adequate occlusions as well as complication rates were similar in Y-stenting and PR group (94.5% vs 96.9% and 8.2% vs 6.2%, respectively). At 6 mo, adequate occlusion was 93.1% after Y-stenting and 84.3% after PR (P = .28), complete occlusion was significantly higher after Y-stenting: 90.3% vs 62.5% (P = .0017). Occlusion grade worsening occurred in 6.9% of Y-stenting and 18.7% of PR patients (P = .09).Neck size was associated with occlusion grade in both groups. Maximal aneurysm size was associated with occlusion grade in the PR group (P = .023) but not in the Y-stenting group (P = .06). After PR, 6-mo occlusion rate was higher in small (< 10 mm) than in large aneurysms (P = .0094); this was not observed after Y-stenting (P = .54).Location did not significantly affect the mid-term occlusion rate in both the groups. After PR, occlusion was more stable in basilar than anterior or middle cerebral artery aneurysms. CONCLUSION Y-stenting and PR are both effective with similar immediate and mid-term results. However, treatment stability seems higher after Y-stenting. Aneurysm size seems to negatively affect PR results.

Background DAWN and DEFUSE-3 trials demonstrated the benefit of endovascular thrombectomy in late-presenting acute ischemic strokes due to anterior circulation large vessel occlusion. The aim of our study is to evaluate results of endovascular thrombectomy in large intracranial vessel occlusion without perfusion CT patient selection. Methods we reviewed our prospectively collected endovascular databases for patients with an acute stroke from March 2016 to October 2018, treated after 6 h from stroke onset, without perfusion CT selection. Baseline characteristics, procedural data, and outcomes were evaluated. A good outcome was defined as a 90-day modified Rankin Scale score of 0–2. The association between clinical and procedural parameters and functional outcome was assessed. Results out of 212 patients 55 were treated after 6 h from stroke onset, 49 of which for an anterior circulation occlusion. 18/49 were functional independent at 90 days (mRS 0–2), Successful recanalization (mTICI 2b to 3) was achieved in 38/49 patients (77 %). Multivariate logistic regression indicated that a low baseline NIHSS was associated with favorable outcome (OR 0.66, 95 % CI 0.52−0.83, p-value 0.001). Conclusions in our retrospective analysis, baseline NIHSS is the only parameter that can predict good outcome (90-days mRS 0–2). We confirm data from recent papers assessing that perfusion CT can provide a better patients' selection compared to mCTA for large vessels occlusion treated beyond six hours from symptom onset.

Brain death (BD) is defined as the irreversible destruction of all brain functions. It is usually diagnosed through a clinical examination, but in certain circumstances, ancillary examinations (such as digital subtraction angiography (DSA), transcranial color Doppler (TCD), computed tomography angiography (CTA), magnetic resonance angiography (MRA), or radionuclide scanning) are required as confirmatory tests. In many countries, cervical color Doppler sonography (CCD) is not recognized as a valid test. The aim of our study is to assess its accuracy as a non-invasive, inexpensive, and easily available examination to determine cerebral circulatory arrest (CCA). We performed a retrospective study in which 123 patients with clinical diagnosis of BD underwent bedside cervical color Doppler as an additional examination for CCA assessment. We compared these cervical color Doppler findings with the results of validated ancillary tests such as CTA, TCD, and DSA. Cervical color Doppler exams showed a sensitivity of 78% (96/123 patients) in detecting CCA compared to standard ancillary tests. Twenty-seven patients showed a persistent diastolic flow in one or two of the four arterial vessels examined and thus considered as false negatives. Our results show that cervical color Doppler may become a reliable and safe technique in detecting CCA, which can shorten the time for declaring brain death. In particular, in patients lacking good bone windows at transcranial color Doppler, cervical color Doppler of the cervical internal carotids and vertebral arteries could be recommended to increase the sensitivity of transcranial color Doppler, or as an alternative bedside examination.