Middle Cerebral Artery Main Stem Research Articles

Bifurcation occlusions and endovascular treatment outcome in acute ischemic stroke

BackgroundA thrombus in the M1 segment of the middle cerebral artery (MCA) can occlude this main stem only or extend into the M1-M2 bifurcation. The occlusion pattern may affect endovascular...

ADAPT First-Line Strategy for MCA Mainstem Occlusion; Analysis for Optimal Salvage Therapy and its Related Factor

ObjectivesA direct first-pass aspiration technique (ADAPT) is an attractive interventional technique for mechanical thrombectomy (MT), which could achieve recanalization quickly and safely at a small amount of material resources. To clarify its usefulness, our ADAPT first-line strategy for middle cerebral artery (MCA)-mainstem occlusion was retrospectively analyzed. Materials and MethodsWe reviewed 54 consecutive patients who underwent MT for MCA-mainstem occlusion using ADAPT first-line strategy. A salvage procedure was concurrently conducted in cases that failed to achieve successful recanalization by ADAPT attempt alone. Procedural and clinical outcome were assessed in both ADAPT alone and Salvage groups. Further investigation was performed in cases that required salvage procedure to determine the reason, risk factors, and optimal procedure. ResultsForty-one patients (75.9%) were able to achieve successful recanalization with ADAPT technique alone. In salvage group, the procedural time was longer, and rates of successful recanalization were lower than in ADAPT-alone group. No significant difference in the rates of favorable outcomes was observed. Among 13 patients who required salvage therapy, the major reason (eight cases) was intra-procedural “thrombus distal migration”. Failure of recanalization was seen in two cases due to “inaccessibility”. In patients who had “thrombus distal migration”, occlusion in the proximal portion was more frequently observed than in patients who did not (p = 0.032, 63.6% vs. 23.3%). ConclusionsOur ADAPT first-line strategy for MCA-mainstem occlusion demonstrated favorable procedural and clinical outcomes, even in cases that required additional procedures. Further investigation and better understanding are required to refine this promising procedure.

Predictors for basal ganglia viability after mechanical thrombectomy in proximal middle cerebral artery occlusion

Background/purposeIn acute proximal middle cerebral artery (MCA) occlusion covering the lenticulostriate arteries (LSA), ischemic tolerance of basal ganglia is limited due to supposed lack of collateral supply. However, in several patients, basal ganglia (BG) infarction was absent after successful mechanical thrombectomy (MTE). Purpose of our study was to evaluate predictors for BG viability in stroke patients despite prolonged MCA mainstem occlusion. Material/methodsWe retrospectively reviewed all stroke patients from our local registry with MCA mainstem occlusion after mechanical thrombectomy between November 2009 and October 2016. All patients underwent non-enhanced post-interventional cranial CT imaging (NCCT) and were classified according to 6 patterns of BG viability: complete: putamen (P) and globus pallidus (GP); partial: P or GP, and combination of complete or partial BG and/or adjacent white matter/cortical (WMC) viability. We compared viability patterns with respect to pre-interventional stroke imaging including NCCT, CT-angiography (CTA), CT perfusion (CTP); demographics, pre- and intra-procedural data and occurrence of post-procedural intracerebral hematoma (ICH). CTP imaging of the affected and contralateral BG-territories were obtained separately and CTA-collateral score (CS) was assessed. ResultsA significant correlation between higher collateral score and viability of GP (OR = 1.949; p = .011), P (OR = 2.039, p = .011), and the combination of GP, P and WMC (OR = 2.767, p = .007) was revealed. Higher relative CBV ratio (rCBVR) was significantly associated with viability of the pattern GP + WMC (univariate: OR = 3.160, p = .014; multivariate: OR = 6.058; p = .021). ConclusionCTA collateral score and rCBVR were predictive for BG viability in stroke patients after successful MTE in prolonged complete MCA-mainstem and LSA occlusion.

A Retrospective Single-Center Case Series of Direct Aspiration Thrombectomy as First-Line Approach in Ischemic Stroke and Review of the Literature

Introduction: The benefit of the direct aspiration thrombectomy (ADAPT) technique for the treatment of ischemic stroke due to large vessel occlusion are challenged after publishing of the ASTER trial that failed to show superiority of ADAPT compared to stent retriever. Aim of the present single-center study was a retrospective evaluation of the ADAPT technique comparing our results with literature. Material/methods: We retrospectively analyzed institutional data of stroke procedures in patients with mainstem occlusion of the middle cerebral artery treated between November 2016 and December 2017 with an initial attempt of manual thrombaspiration. Reperfusion rate (thrombolysis in cerebral infarction), procedural times, early clinical outcome and complications were recorded. Results: Forty patients were treated by using direct thrombaspiration in middle cerebral artery mainstem occlusion. Median age was 67.5 (±17.8) years (m = 27.5%). Median Baseline National Institutes of Health Stroke Scale score was 12 (IQR 7) preintervention and 3 (IQR 11) postintervention. Twenty-eight (70%) patients received intravenous thrombolysis. Successful recanalization (modified thrombolysis in cerebral infarction ≥ 2b) could be achieved in 85% with direct aspiration alone. Mean time from groin puncture to recanalization was 25.2 ± 14.3 minutes. Embolization to new territories occurred in 1 of 40 (2.5%) cases and symptomatic intracranial hemorrhage in 3 of 40 (7.5%). Nineteen of 40 (47.5%) patients achieved favorable outcome (modified Rankin scale 0-2) at discharge. Conclusions: The ADAPT technique presented as a safe and efficient first-line recanalization strategy with good clinical outcome for treatment of acute ischemic stroke resulting from large vessel occlusions in this single-center study and review of the literature. However, the concept of ADAPT as an equivalent first-line approach to stent retriever thrombectomy has to be proven by future randomized studies.

CT Angiography of Collateral Vessels and Outcomes in Endovascular-Treated Acute Ischemic Stroke Patients.

Background and PurposeMeasuring the extent of the collateral blood vessels using computed tomography (CT) angiography source images may promote tissue survival and functional gain in acute ischemic stroke patients who are candidates for endovascular recanalization treatment.MethodsOf 5,558 acute stroke patients registered in a prospective clinical stroke registry, 104 met the selection criteria of endovascular recanalization treatment for internal cerebral artery or middle cerebral artery main-stem (M1) occlusions and presented for treatment ≤4 hours after the event. Using CT angiography source images, two independent and blinded reviewers measured the extent of collateral circulations at four regions, with good interrater reliability. The functional recovery at 3 months after stroke was used as an outcome variable.ResultsCases with a sufficient collateral circulation at the Sylvian fissure showed significantly increased likelihood of having a modified Rankin Scale score of ≤2 at 3 months after stroke (adjusted odds ratio=3.03, 95% confidence interval=1.19–7.73, p=0.02), but the association became nonsignificant after adding the infarct volume to the model (p=0.65). The association between leptomeningeal convexity collaterals and functional recovery was no longer significant after adjusting for the infarct volume (p=0.28). The natural indirect effect of infarct volume on functional recovery was significant for both the Sylvian fissure (p=0.03) and leptomeningeal convexity (p=0.02) collaterals.ConclusionsThe extent of collateral circulation at the Sylvian fissure was significantly associated with functional recovery, which may be mediated via the volume of the final infarction.

Impact of the Implementation of Thrombectomy with Stent Retrievers on the Frequency of Hemicraniectomy in Patients with Acute Ischemic Stroke.

The increasing use of endovascular treatments has led to higher recanalization rates and better clinical outcomes compared with intravenous thrombolysis alone. Stent retrievers represent the latest development for recanalization of large vessel occlusions. Decompressive hemicraniectomy has proved beneficial in patients suffering from rising intracranial pressure after malignant stroke. We investigated the effect of the implementation of stent retriever treatment on the frequency of hemicraniectomy as a surrogate marker for infarct size and thus for poor neurological outcome. Patients with acute ischemic stroke were retrospectively studied. We compared the frequency of hemicraniectomy following proximal artery occlusion of the internal carotid artery and middle cerebral artery main stem in the years before (2009 and 2010) and after (2012 and 2013) introducing stent retrievers. Overall, 497 patients with proximal arterial occlusion were included in the study. Of 253 patients admitted in the years 2009 and 2010 44 (17.4 %) and of 244 patients admitted in 2012 and 2013, 20 (8.2 %) received a hemicraniectomy. This decrease in the proportion of hemicraniectomies was statistically significant (p < 0.01). The findings in this study illustrate a significantly reduced rate of hemicraniectomies in patients with proximal artery occlusions after implementation of thrombectomy with stent retriever. Hereby, we could show a significant reduction of malignant infarctions after thrombectomy with stent retriever.

A simple brain atrophy measure improves the prediction of malignant middle cerebral artery infarction by acute DWI lesion volume

In patients with malignant middle cerebral artery infarction (MMI) decompressive surgery within 48 h improves functional outcome. In this respect, early identification of patients at risk of developing MMI is crucial. While the acute diffusion weighted imaging (DWI) lesion volume was found to predict MMI with high predictive values, the potential impact of preexisting brain atrophy on the course of space-occupying middle cerebral artery (MCA) infarction and the development of MMI remains unclear. We tested the hypothesis that the combination of the acute DWI lesion volume with simple measures of brain atrophy improves the early prediction of MMI. Data from a prospective, multicenter, observational study, which included patients with acute middle cerebral artery main stem occlusion studied by MRI within 6 h of symptom onset, was analyzed retrospectively. The development of MMI was defined according to the European randomized controlled trials of decompressive surgery. Acute DWI lesion volume, as well as brain and cerebrospinal fluid volume (CSF) were delineated. The intercaudate distance (ICD) was assessed as a linear brain atrophy marker by measuring the hemi-ICD of the intact hemisphere to account for local brain swelling. Binary logistic regression analysis was used to identify significant predictors of MMI. Cut-off values were determined by Classification and Regression Trees analysis. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the resulting models were calculated. Twenty-one (18 %) of 116 patients developed a MMI. Malignant middle cerebral artery infarctions patients had higher National Institutes of Health Stroke Scale scores on admission and presented more often with combined occlusion of the internal carotid artery and MCA. There were no differences in brain and CSF volume between the two groups. Diffusion weighted imaging lesion volume was larger (p < 0.001), while hemi-ICD was smaller (p = 0.029) in MMI patients. Inclusion of hemi-ICD improved the prediction of MMI. Best cut-off values to predict the development of MMI were DWI lesion volume > 87 ml and hemi-ICD ≤ 9.4 mm. The addition of hemi-ICD to the decision tree strongly increased PPV (0.93 vs. 0.70) resulting in a reduction of false positive findings from 7/23 (30 %) to 1/15 (7 %), while there were only slight changes in specificity, sensitivity and NPV. The absolute number of correct classifications increased by 4 (3.4 %). The integration of hemi-ICD as a linear marker of brain atrophy, that can easily be assessed in an emergency setting, may improve the prediction of MMI by lesion volume based predictive models.

Predictors of re-canalisation in acute cerebral infarction from occlusion of the terminal internal carotid artery or of the middle cerebral artery mainstem treated with thrombolysis

Objective: We have evaluated the factors of unsuccessful re-canalisation in a large series of patients with hemispheric cerebral infarction treated with thrombolysis. Patients and methods: All patients aged 18–80 years with an acute hemispheric infarction, admitted within the first few hours of symptoms onset, were immediately submitted to Magnetic Resonance both Imaging (MRI) and Angiography (MRA). MRI and MRA were repeated at 24 h of stroke. Re-canalisation was attributed if grade 2 or 3 of Thrombolysis in Myocardial Infarction (TIMI) criteria for the myocardial infarction. Outcome was rated at three months of stroke. Re-canalisation was matched with ageing and with the common risk factors for stroke. Results: One hundred and twenty-one patients, 70 men and 51 women, with a median age of 67 years, were included. Re-canalisation was seen in 62 patients (51%). Twenty-three patients (19%) died by 90 days of stroke. Re-canalisation was associated to survival (1 death vs. 22, p < 0.0001). Regression analysis retained advanced age (Odds ratio 0.37, 95% Confidence interval 0.13–0.98), baseline National Institute of Health Stroke Scale (NIHSS) (Odds ratio 0.94, 95% Confidence interval 0.89–0.98) and diabetes mellitus (Odds ratio 0.28, 95% Confidence interval 0.09–0.84) as factors contrasting re-canalisation. Conclusions: Our study indicates that in patients with proven occlusion of the terminal segment of the internal carotid artery and/or of the mainstem of the Middle Cerebral Artery, re-canalisation at 24 h of the acute ischemic stroke is dramatically associated with survival, and halted by advanced age and diabetes mellitus.

O-021 Endovascular treatment significantly improves outcomes compared to IV thrombolysis for strokes secondary to large vessel occlusions. 8-year experience

IntroductionNew thrombectomy devices for acute ischemic stroke (AIS) may allow endovascular therapy (EVT) to gain traction. However for EVT to have a significant impact on stroke it has to demonstrate...

Outcome of MRI-based intravenous thrombolysis in carotid-T occlusion

Low recanalization rates and poor clinical outcome have been reported after intravenous thrombolysis (IV-tPA) in carotid-T occlusion (CTO). We studied clinical outcome and imaging findings of MRI-based intravenous thrombolysis in CTO. Data of patients with acute ischemic stroke and CTO treated with IV-tPA within 6 h of symptom onset based on MRI criteria were retrospectively analyzed. Vessel occlusion was defined based on MR angiography. Acute diffusion and perfusion lesion volumes and final infarct volumes after 3-7 days were delineated. The National Institutes of Health Stroke Scale (NIHSS) was used to assess the neurological deficit on admission. Recanalization was evaluated after 24 h. Clinical outcome was assessed using the modified Rankin Scale (mRS) after 90 days. Clinical and imaging data were compared to patients with middle cerebral artery main stem occlusion (MCAO). A total of 20 patients with CTO and 51 patients with MCAO were studied. Onset to treatment time, NIHSS on admission, initial diffusion and perfusion lesion volumes, and recanalization rates after 24 h were similar between groups. Final infarct volume was larger for CTO (82 vs. 30 ml, p = 0.006). Although overall outcome was not significantly different between groups (p = 0.251), independent outcome (mRS 0-2) tended to be less frequent in CTO (17 vs. 39 %), while poor outcome (mRS 4-6) appeared more common (72 vs. 43 %). The proportion of patients with good clinical outcome after intravenous thrombolysis in CTO is small. Moreover, final infarct volume is larger and clinical outcome appears to be worse compared to MCAO.

Prediction of malignant middle cerebral artery infarction by magnetic resonance imaging within 6 hours of symptom onset: A prospective multicenter observational study

Early identification of patients at risk of space-occupying "malignant" middle cerebral artery (MCA) infarction (MMI) is needed to enable timely decision for potentially life-saving treatment such as decompressive hemicraniectomy. We tested the hypothesis that acute stroke magnetic resonance imaging (MRI) predicts MMI within 6 hours of stroke onset. In a prospective, multicenter, observational cohort study patients with acute ischemic stroke and MCA main stem occlusion were studied by MRI including diffusion-weighted imaging (DWI), perfusion imaging (PI), and MR-angiography within 6 hours of symptom onset. Multivariate regression analysis was used to identify clinical and imaging predictors of MMI. Of 140 patients included, 27 (19.3%) developed MMI. The following parameters were identified as independent predictors of MMI: larger acute DWI lesion volume (per 1 ml odds ratio [OR] 1.04, 95% confidence interval [CI] 1.02-1.06; p < 0.001), combined MCA + internal carotid artery occlusion (5.38, 1.55-18.68; p = 0.008), and severity of neurological deficit on admission assessed by the National Institutes of Health Stroke Scale score (per 1 point 1.16, 1.00-1.35; p = 0.053). The prespecified threshold of a DWI lesion volume >82 ml predicted MMI with high specificity (0.98, 95% CI 0.94-1.00), negative predictive value (0.90, 0.83-0.94), and positive predictive value (0.88, 0.62-0.98), but sensitivity was low (0.52, 0.32-0.71). Stroke MRI on admission predicts malignant course in severe MCA stroke with high positive and negative predictive value and may help in guiding treatment decisions, such as decompressive surgery. In a subset of patients with small initial DWI lesion volumes, repeated diagnostic tests are required.

Disappearing Hyperdense Middle Cerebral Artery Sign Is Associated with Striatocapsular Infarcts on Follow-Up CT in Ischemic Stroke Patients Treated with Intravenous Thrombolysis

Background: A striatocapsular infarct (SCI) is a subcortical infarct in the territory of the lenticulostriate arteries, most likely due to transient occlusion of the main stem of the middle cerebral artery (MCA). Presence of the hyperdense middle cerebral artery sign (HMCAS) is a reliable marker of occlusion of the MCA. We hypothesized that SCIs are related to HMCAS at baseline, which subsequently disappears (HMCAS-D) on follow-up CT in stroke patients treated with intravenous rtPA. Methods: Baseline and 24-hour follow-up CTs were evaluated for HMCAS in acute ischemic stroke patients treated with intravenous rtPA and follow-up scans were also reviewed for the presence of isolated cortical (CIn), SCI, cortical and striatocapsular (CI-SCI) or lacunar infarct. We determined the incidence of SCI and the association between SCI and HMCAS on baseline and follow-up CT. Results: Of the 247 patients, 43 had an SCI (17.4%; 95% CI: 13.1–22.5). The presence of HMCAS at baseline was related to the occurrence of infarction with involvement of the striatocapsular region (SCI or CI-SCI) on follow-up CT (OR: 11.6; 95% CI: 5.9–22.8). HMCAS-D on follow-up scans was significantly related to SCI on follow-up CT compared to CI-SCI (OR: 4.9; 95% CI: 3.7–6.1). Conclusions: Occurrence of SCI and CI-SCI is associated with the presence of HMCAS on CT before thrombolysis, whereas HMCAS-D on follow-up CT is strongly related to the occurrence of SCI. Our findings support the causative role of transient occlusion of the MCA main stem in the pathogenesis of SCI.

Transcranial Duplex Sonography and CT Angiography in Acute Stroke Patients

Acute occlusion of cervical or intracranial arteries is the most common cause of ischemic stroke (IS). The aims of the current study were to compare the occurrence of acute pathologic findings in intracranial arteries using transcranial color-coded sonography (TCCS) and computed tomographic angiography (CTA) performed within 3 hours of IS onset and to assess the correlation between the vascular findings on admission and the patient's clinical state on admission and 3 months after the IS. Forty-five consecutive patients with an acute IS were included in the prospective study during an 18-month period. All patients underwent CTA and TCCS within the first 3 hours of symptom onset. A high rate of pathologic findings in the intracranial circulation was found (70.9% in CTA and 77.4% in TCCS examinations). The CTA and TCCS findings with respect to the intracranial arteries were consistent in 87.1% of cases (Cohen's kappa, .797). The sensitivity, specificity, and positive and negative predictive values achieved with TCCS in patients with middle cerebral artery main stem occlusion were 92.3%, 94.4%, and 92.3% and 94.4%, respectively. There was no correlation between the patient's clinical status on admission and 3 months after the onset of the IS and the CTA or the TCCS findings (P > .1 in all cases). A substantial agreement was found between TCCS and CTA in the detection of pathologic findings in intracranial vessels in acute stroke patients. Both methods can be used for this purpose.

Ultrasound-Enhanced Thrombolysis: From Bedside to Bench

HomeStrokeVol. 39, No. 12Ultrasound-Enhanced Thrombolysis: From Bedside to Bench Free AccessLetterPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessLetterPDF/EPUBUltrasound-Enhanced Thrombolysis: From Bedside to Bench Jürgen Eggers, MD Jürgen EggersJürgen Eggers Stroke Unit, Department of Neurology, Asklepios Hospital North, Hamburg, Germany Search for more papers by this author Originally published23 Oct 2008https://doi.org/10.1161/STROKEAHA.108.531848Stroke. 2008;39:e193Other version(s) of this articleYou are viewing the most recent version of this article. Previous versions: October 23, 2008: Previous Version 1 To the Editor:We highly appreciate Tsivgoulis and Alexandrov’s1 comment regarding our article about sonothrombolysis with transcranial color-coded sonography (TCCS) and recombinant tissue plasminogen activator.2 However, several conclusions made by these colleagues require a response. The assumption that the multibeam configuration of TCCS causes an increased rate of symptomatic intracranial hemorrhage in the target group is not justified. The overwhelming part of insonation was performed by using the pulsed wave Doppler mode as it was also used by Alexandrov and coworkers in the CLOTBUST trial.3 As we described in the Methods section, multibeam color-coded mode was only used for the identification of the vessel occlusion before starting the continuous insonation.2 Additionally, the exact location of the Doppler sample volume at the targeted occlusion site was recurrently proved by intermitted switching from the Doppler mode to the color-coded mode. This interval of switching depends on the examiner’s choice, either using the so called “refreshing-mode” of the device for an ultrashort period (every 7 seconds during continuous insonation for enhancing thrombolysis in our study) or individually when used for diagnostic purpose. This frequent visualization of the Doppler sample volume location allows optimal targeting of the occlusion site by the ultrasound beam. Because the position of transducer at the acoustic window of the temporal bone did not change, the insonation angle did not vary remarkably.This ability of switching from Doppler mode to color-coded mode by using the same device and transducer makes TCCS such an advanced and useful tool for identifying (and treating) acute intracranial vessel occlusion.2,4 As the pulsed wave Doppler mode enables to measure blood flow velocities at a defined location, the color-coded mode displays the flow of the major part of the Circle of Willis at one glance. Also, the modality of brightness-mode is helpful to identify landmarks which allow locating the site of an occluded middle cerebral artery without any residual flow (like in our study) in Doppler or color-coded mode.The statement by Tsivgoulis that there was only a trend toward a better functional outcome after 90 days as determined by both the modified Rankin Scale and the Barthel Index does not reflect the results of our study correctly. The modified Rankin Scale showed only a trend, but the Barthel Index measurement revealed a highly significant improvement of the target group. However, the Barthel Index is no longer accepted as an end point for stroke trials, so we did not regard this result as valid.Both transcranial Doppler ultrasound and TCCS enhance thrombolysis by the same high-frequency low-energy “diagnostic” transcranial pulsed wave ultrasound. However, in our opinion TCCS is the more advanced tool offering many advantages compared to transcranial Doppler ultrasound.DisclosuresNone.1 Tsivgoulis G, Alexandrov AV. Ultrasound-enhanced thrombolysis from bedside to bench. Stroke. 2008; 39: 1404–1405.LinkGoogle Scholar2 Eggers J, König IR, Koch B, Händler G, Seidel G. Sonothrombolysis with transcranial color-coded sonography and recombinant tissue-type plasminogen activator in acute middle cerebral artery main stem occlusion: results from a randomized study. Stroke. 2008; 39: 1470–1475.LinkGoogle Scholar3 Alexandrov AV, Molina CA, Grotta JC, Garami Z, Ford SR, Alvarez-Sabin J, Montaner J, Saqqur M, Demchuk AM, Moye LA, Hill MD, Wojner AW; CLOTBUST Investigators. Ultrasound-enhanced systemic thrombolysis for acute ischemic stroke. N Engl J Med. 2004; 351: 2170–2178.CrossrefMedlineGoogle Scholar4 Gerriets T, Postert T, Goertler M, Stolz E, Schlachetzki F, Sliwka U, Seidel G, Weber S, Kaps M. DIAS I: duplex-sonographic assessment of the cerebrovascular status in acute stroke: a useful tool for future stroke trials. Stroke. 2000; 31: 2342–2345.CrossrefMedlineGoogle Scholar Previous Back to top Next FiguresReferencesRelatedDetails December 2008Vol 39, Issue 12 Advertisement Article InformationMetrics https://doi.org/10.1161/STROKEAHA.108.531848PMID: 18948600 Originally publishedOctober 23, 2008 PDF download Advertisement

Sonothrombolysis With Transcranial Color-Coded Sonography and Recombinant Tissue-Type Plasminogen Activator in Acute Middle Cerebral Artery Main Stem Occlusion

Sonothrombolysis is a new treatment approach in acute ischemic stroke. The results of a monocenter, randomized clinical study are presented. Subjects with acute middle cerebral artery main stem occlusion were randomized into a target group receiving 1-hour transcranial continuous insonation using a 1.8-MHz Doppler ultrasound (US) probe or a control group. All underwent standard thrombolysis with intravenous recombinant tissue-type plasminogen activator. Thirty-seven subjects were included; 19 subjects were treated in the target (US) group and 18 in the control (no-US) group, all with no residual flow in the middle cerebral artery main stem occlusion (Thrombolysis in Brain Ischemia recanalization grade 0). Compared with the no-US group, the US group showed greater improvement in National Institutes of Health Stroke Scale values at days 1 and 4 and a higher median Thrombolysis in Brain Ischemia grade 1 hour after recombinant tissue-type plasminogen activator initiation. Recanalization (complete or partial) after 1 hour occurred in 57.9% of the US group and 22.2% of the no-US group (P=0.045). After 90 days, 4 subjects from the US group had a modified Rankin Score <or=1 (none from the no-US group) and 8 had a Barthel Index >or=95 (none from the no US group; P=0.106 and P=0.003, respectively). Three subjects from the US group (15.8%) developed a symptomatic intracranial hemorrhage as did one (5.6%) in the no-US group (P=0.60). This small randomized study indicates a beneficial impact of transcranial ultrasound on recanalization and short-term outcome in subjects with middle cerebral artery main stem occlusion and recombinant tissue-type plasminogen activator treatment.

Effect of incomplete (spontaneous and postthrombolytic) recanalization after middle cerebral artery occlusion: a magnetic resonance imaging study.

Early reperfusion is one of the best predictors of good outcome after acute middle cerebral artery (MCA) occlusion. The purpose of this study was to analyze the frequency and relevance of incomplete recanalization for tissue and clinical outcome. From a larger acute stroke database (Kompetenznetzwerk Schlaganfall B5), all patients (n=82) with MCA main stem occlusion (excluding carotid T-occlusions) were selected. These patients had received a multiparametric stroke MRI protocol including diffusion- and perfusion-weighted imaging (DWI, PWI) and MR angiography (MRA) within 6 hours after symptom onset, at day 1 and after 1 week. Recanalization status was determined with MRA on day 1 (according to Thrombolysis In Myocardial Infarction flow grades) and used to group patients into those with persistent occlusion (0) or minimal (1), partial (2), or complete (3) recanalization. Incomplete recanalization according to MRI criteria was found in 39 patients (grade 1: n=20; grade 2: n=19), complete recanalization in 10, and persistent occlusion in 33. There was no statistically significant difference in any of the clinical (National Institutes of Health Stroke Scale score) or MRI baseline parameters (DWI lesion, PWI deficit, mismatch volume, mismatch ratio). However, lesion growth was smaller in patients with recanalization (even in patients with only minimal recanalization) and outcome was related to the degree of recanalization (mean modified Rankin score at 90 days: 3.36, 2.70, 1.79, and 1.44 for the groups with no, minimal, partial, and complete recanalization, respectively). Both incomplete and complete recanalization was more frequent in patients receiving thrombolysis. Incomplete recanalization on day 1 is a frequent MR finding after MCA main stem occlusion, indicating a more favorable clinical course than persistent occlusion. MR indicators of early recanalization could be useful surrogates of efficacy in thrombolytic trials.

Feasibility and validity of transcranial duplex sonography in patients with acute stroke

Objectives: To evaluate in a prospective multicentre setting the feasibility of transcranial colour coded duplex sonography (TCCS) for examination of the middle cerebral artery (MCA) in patients with acute hemispheric...

Detection of stenoses in the anterior circulation using frequency-based transcranial color-coded sonography

Atherosclerotic stenoses of the intracranial vessels are less frequent than those of the extracranial vessels, but they are associated with a considerable annual stroke rate. The aim of the present study was to investigate the usefulness of frequency-based transcranial color-coded sonography (TCCS), transcranial Doppler sonography (TCD) and digital subtraction angiography (DSA) in patients with middle cerebral artery (MCA) and intracranial internal carotid artery (ICA) stenosis. Forty patients presenting with 48 intracranial stenoses of the anterior circulation were involved in the study. The stenoses were detected in the neurovascular laboratory during routine TCD examinations. All patients underwent an additional frequency-based TCCS examination. Both the axial and coronal planes were obtained to allow the exact localization of MCA stenosis and differentiation from intracranial ICA stenosis. Angle-corrected flow velocity measurements were performed if straight vessel compartments were 20 mm or more in length. A total of 18 stenoses (44%) were investigated additionally with DSA. According to the investigation with TCD, 20 (42%) stenoses were low-grade, 12 (25%) were moderate, and the remaining 16 (33%) were severe. Angle-corrected flow velocity measurements obtained with the integrated pulse-wave Doppler device of the TCCS machine were highly correlated (0.912, p < 0.001) with those obtained with TCD. TCCS achieved a reliable differentiation of MCA main stem stenosis vs. intracranial ICA stenosis in 7 patients and vs. MCA branch stenosis in 4 patients, but TCD failed in these two subgroups. The agreement between DSA and TCCS to evaluate semiquantitatively 18 intracranial stenoses resulted in a weighted-kappa value of 0.764. The major clinically relevant advantages of TCCS over TCD in MCA stenosis are its ability to differentiate MCA trunk stenosis from terminal ICA or MCA branch stenosis reliably and to perform angle-corrected flow velocity measurements.

Contrast-enhanced transcranial color-coded sonography in acute hemispheric brain infarction.

The aim of the present study was to investigate the diagnostic potential of contrast-enhanced transcranial color-coded real-time sonography (CE-TCCS) in otherwise ultrasound-refractory acute stroke patients with an ischemia in the territory of the middle cerebral artery (MCA). Furthermore, correlations of CE-TCCS findings with clinical, angiographic, and CT results were investigated. In 90 acute stroke patients with inadequate insonation conditions in unenhanced transcranial color-coded real-time sonography (TCCS) examinations, CE-TCCS, clinical, angiographic, and CT examinations were performed within 12 hours, 36 hours (CE-TCCS only), and 1 week after onset of clinical symptoms. A CT angiography (CTA) as reference method was available in 39 individuals. After application of a galactose-based echo-enhancing agent, the portion of conclusive ultrasound examinations of the MCA, as manifested by an MCA occlusion, decreased or increased flow velocity (FV), and symmetrical MCA FV, was evaluated. CE-TCCS findings on admission and during follow-up were correlated with infarction size as demonstrated on follow-up CT, and clinical findings were assessed by use of the European Stroke Scale. Adequate diagnosis was achieved in 74 of 90 patients (82%) by the use of echo contrast agents. MCA occlusion or reduction of MCA FV was found in 20 and 27 patients, respectively. MCA occlusion was confirmed by CTA in 17 cases. In one individual, false-positive diagnosis of MCA occlusion was made according to ultrasound criteria. In 5 patients with MCA occlusion, vessel recanalization was observed during follow-up; 15 of 27 patients with decreased flow velocities showed normalization after the third examination that was associated with a significantly better clinical outcome (P<0.0001). Furthermore, MCA occlusion or decreased FV in the first 12 hours were associated with significantly larger infarctions in the MCA territory compared with normal CE-TCCS findings (P<0.0001). CE-TCCS enables adequate diagnosis in approximately 80% of acute hemispheric stroke patients with insufficient unenhanced TCCS examinations. It is a reliable diagnostic tool regarding MCA mainstem and branch occlusions. Because this method conveys useful information concerning cerebral tissue and clinical prognosis, it may be useful to identify those patients who benefit most from local or intra-arterial thrombolytic therapy.

Diagnosis and Monitoring of Middle Cerebral Artery Occlusion with Contrast-Enhanced Transcranial Color-Coded Real-Time Sonography in Patients with Inadequate Acoustic Bone Windows

Transcranial color-coded real-time sonography (TCCS) is an emerging diagnostic technique that allows noninvasive imaging of intracranial vessels within parenchymal structures. However, in some patients, transcranial ultrasound is particularly hindered by insufficient ultrasound penetration through the temporal bone. The present study evaluates whether or not application of an echo-contrast agent in ultrasound-refractory patients with middle cerebral artery (MCA) trunk occlusion enhances image acquisition enough to yield accurate diagnoses. Contrast-enhanced (CE) TCCS examinations, computed tomography scans and angiographic studies were performed in 20 patients with clinical symptoms suggestive of MCA occlusion within 12 h of the onset of symptoms. For comparison, 20 control persons without history or clinical signs for cerebrovascular diseases were examined using CE-TCCS. In none of the patients or control subjects did unenhanced TCCS investigations depict any color-coded vascular signal of an intracranial vessel. After application of 9 mL of 400 mg/mL galactose-based microbubbles, CE-TCCS was performed. In subjects with MCA occlusion, CE-TCCS examinations were repeated within 24 h, 48 h and 5 days after stroke. In stroke patients ( n = 20), CE-TCCS showed an occluded MCA main stem in 11 patients, and this vessel was clearly demonstrable on the unaffected side. On the affected side, the posterior cerebral artery (PCA) and anterior cerebral artery (ACA) could be visualized in 8 of 11 subjects; in 3 patients, at least 1 of these vessels was detectable. Angiographic studies confirmed the diagnosis of MCA trunk occlusion in all 11 individuals. In follow-up investigations, 3 stroke patients had angiographic and CE-TCCS examinations consistent with vessel reperfusion. Nine stroke patients had a patent MCA shown in angiographic and CE-TCCS examinations. In the control group, the MCA trunk could be visualized in all subjects by CE-TCCS. CE-TCCS is a sensitive and specific ultrasound method for the diagnosis of MCA trunk occlusion that overcomes the anatomical hindrance of inadequate acoustic bone window. This technique may help to identify patients suitable for thrombolytic therapies and monitor their response.