RAPID CT Perfusion-Based Relative CBF Identifies Good Collateral Status Better Than Hypoperfusion Intensity Ratio, CBV-Index, and Time-to-Maximum in Anterior Circulation Stroke.

BACKGROUND AND PURPOSE: Information of collateral flow may help to determine eligibility for thrombectomy. Our aim was to identify CT perfusion-based surrogate parameters of good collateral status in acute anterior circulation ischemic stroke. MATERIALS AND METHODS: In this retrospective study, we assessed the collateral status of 214 patients who presented with acute ischemic stroke due to occlusion of the MCA M1 segment or the carotid terminus. Collaterals were assessed on dynamic CTA images analogous to the multiphase CTA score by Menon et al. CT perfusion parameters (time-to-maximum, relative CBF, hypoperfusion intensity ratio, and CBV-index) were assessed with RAPID software. The Spearman rank correlation and receiver operating characteristic analyses were performed to identify the parameters that correlate with collateral scores and good collateral supply (defined as a collateral score of ≥4). RESULTS: The Spearman rank correlation was highest for a relative CBF < 38% volume (ρ = -0.66, P < .001), followed by the hypoperfusion intensity ratio (ρ = -0.49, P < .001), CBV-index (ρ = 0.51, P < .001), and time-to-maximum > 8 seconds (ρ = -0.54, P < .001). Good collateral status was better identified by a relative CBF < 38% at a lesion size <27 mL (sensitivity of 75%, specificity of 80%) compared with a hypoperfusion intensity ratio of <0.4 (sensitivity of 75%, specificity of 62%), CBV-index of >0.8 (sensitivity of 60%, specificity of 78%), and time-to-maximum > 8 seconds (sensitivity of 68%, specificity of 76%). CONCLUSIONS: Automated CT perfusion analysis allows accurate identification of collateral status in acute ischemic stroke. A relative CBF < 38% may be a better perfusion-based indicator of good collateral supply compared with time-to-maximum, the hypoperfusion intensity ratio, and the CBV-index.

Automated detection and segmentation of intracranial hemorrhage suspect hyperdensities in non-contrast-enhanced CT scans of acute stroke patients.

OBJECTIVES: Artif icial intelligence (AI)-based image analysis is increasingly applied in the acute stroke field. Its implementation for the detection and quantification of hemorrhage suspect hyperdensities in non-contrast-enhanced head CT (NCCT) scans may facilitate clinical decision-making and accelerate stroke management. METHODS: NCCTs of 160 patients with suspected acute stroke were analyzed regarding the presence or absence of acute intracranial hemorrhages (ICH) using a novel AI-based algorithm. Read was performed by two blinded neuroradiology residents (R1 and R2). Ground truth was established by an expert neuroradiologist. Specificity, sensitivity, and area under the curve were calculated for ICH and intraparenchymal hemorrhage (IPH) detection. IPH-volumes were segmented and quantified automatically by the algorithm and semi-automatically. Intraclass correlation coefficient (ICC) and Dice coefficient (DC) were calculated. RESULTS: In total, 79 of 160 patients showed acute ICH, while 47 had IPH. Sensitivity and specificity for ICH detection were 0.91 and 0.89 for the algorithm; 0.99 and 0.98 for R1; and 1.00 and 0.98 for R2. Sensitivity and specificity for IPH detection were 0.98 and 0.89 for the algorithm; 0.83 and 0.99 for R1; and 0.91 and 0.99 for R2. Interreader reliability for ICH and IPH detection showed strong agreements for the algorithm (0.80 and 0.84), R1 (0.96 and 0.84), and R2 (0.98 and 0.92), respectively. ICC indicated an excellent (0.98) agreement between the algorithm and the reference standard of the IPH-volumes. The mean DC was 0.82. CONCLUSION: The AI-based algorithm reliably assessed the presence or absence of acute ICHs in this dataset and quantified IPH volumes precisely. KEY POINTS: • Artificial intelligence (AI) is able to detect hyperdense volumes on brain CTs reliably. • Sensitivity and specificity are highest for the detection of intraparenchymal hemorrhages. • Interreader reliability for hemorrhage detection shows strong agreement for AI and human readers.

Accuracy and Prognostic Role of NCCT-ASPECTS Depend on Time from Acute Stroke Symptom-onset for both Human and Machine-learning Based Evaluation.

PURPOSE: We hypothesize that the detectability of early ischemic changes on non-contrast computed tomography (NCCT) is limited in hyperacute stroke for both human and machine-learning based evaluation. In short onset-time-to-imaging (OTI), the CT angiography collateral status may identify fast stroke progressors better than early ischemic changes quantified by ASPECTS. METHODS: In this retrospective, monocenter study, CT angiography collaterals (Tan score) and ASPECTS on acute and follow-up NCCT were evaluated by two raters. Additionally, a machine-learning algorithm evaluated the ASPECTS scale on the NCCT (e-ASPECTS). In this study 136 patients from 03/2015 to 12/2019 with occlusion of the main segment of the middle cerebral artery, with a defined symptom-onset-time and successful mechanical thrombectomy (MT) (modified treatment in cerebral infarction score mTICI = 2c or 3) were evaluated. RESULTS: Agreement between acute and follow-up ASPECTS were found to depend on OTI for both human (Intraclass correlation coefficient, ICC = 0.43 for OTI < 100 min, ICC = 0.57 for OTI 100-200 min, ICC = 0.81 for OTI ≥ 200 min) and machine-learning based ASPECTS evaluation (ICC = 0.24 for OTI < 100 min, ICC = 0.61 for OTI 100-200 min, ICC = 0.63 for OTI ≥ 200 min). The same applied to the interrater reliability. Collaterals were predictors of a favorable clinical outcome especially in hyperacute stroke with OTI < 100 min (collaterals: OR = 5.67 CI = 2.38-17.8, p < 0.001; ASPECTS: OR = 1.44, CI = 0.91-2.65, p = 0.15) while ASPECTS was in prolonged OTI ≥ 200 min (collaterals OR = 4.21,CI = 1.36-21.9, p = 0.03; ASPECTS: OR = 2.85, CI = 1.46-7.46, p = 0.01). CONCLUSION: The accuracy and reliability of NCCT-ASPECTS are time dependent for both human and machine-learning based evaluation, indicating reduced detectability of fast stroke progressors by NCCT. In hyperacute stroke, collateral status from CT-angiography may help for a better prognosis on clinical outcome and explain the occurrence of futile recanalization.

Vasogenic Brain Edema During Maintenance Hemodialysis : Preliminary Results from Tract-based Spatial Statistics and Voxel-based Morphometry.

BACKGROUND: Hemodialysis (HD), especially when first initiated, can cause neurological deterioration. Presumably this is due to transient cerebral edema, which has been observed using diffusion weighted magnetic resonance imaging (MRI) in experimental and human studies; however, this has not been investigated under maintenance hemodialysis (mHD). Moreover, there are no studies to date investigating regional effects of mHD on grey and white matter volumes. METHODS: In this study eight patients with end stage renal disease (ESRD) were examined immediately before and after mHD sessions with multimodal MRI, including diffusion tensor imaging (DTI) and high-resolution structural imaging. Additionally, eight healthy, age-matched and sex-matched controls were examined for comparison. Data were analyzed using tract-based spatial statistics and voxel-based morphometry. RESULTS: At baseline, ESRD patients had significantly reduced values of fractional anisotropy (FA) and axial diffusivity as well as bilaterally reduced grey matter volume in the insula, compared with controls. After the mHD session, FA further decreased while axial, radial, and mean diffusivity significantly increased ubiquitously throughout the white matter. Voxel-based morphometry revealed a corresponding significant increase in white matter volume in the central right hemisphere and splenium, as well as in cortical grey matter in the anterior medial frontal and cingulate cortex. None of the patients showed neurological deterioration. CONCLUSION: In this study ESRD patients showed white matter changes indicative of chronic microstructural damage when compared with healthy controls, as previously reported. In addition, patients showed signs of a transient extracellular cerebral edema, which has not yet been observed in the absence of neurological symptoms.

Periprocedural Safety and Feasibility of the New LVIS EVO Device for Stent-Assisted Coiling of Intracranial Aneurysms: An Observational Multicenter Study.

BACKGROUND AND PURPOSE: Stent-assisted treatment techniques can be an effective treatment option for intracranial aneurysms. The aim of this study was to evaluate the periprocedural feasibility and safety of the new LVIS EVO stent for the treatment of intracranial aneurysms. MATERIALS AND METHODS: Patients with intracranial aneurysms treated with the LVIS EVO in 11 European neurovascular centers were retrospectively reviewed. Patient and aneurysm characteristics, procedural parameters, immediate grade of occlusion, and technical and clinical complications were assessed. RESULTS: Fifty-seven patients with 59 aneurysms were treated with the LVIS EVO device; 57.6% of the aneurysms were incidental; 15.3% were acutely ruptured; 15.3% were recanalized or residual aneurysms; and 11.9% were treated for symptoms other than acute hemorrhage. The most frequent aneurysm locations were the middle cerebral artery (25.4%) and the anterior communicating artery (22.0%). The rate of immediate successful deployment was 93.2%. In 6.8% (n = 4) of cases, additional in-stent angioplasty was needed. The immediate complete occlusion rate was 54.2%, while there was a residual aneurysm in 35.6% and a residual neck in 10.2%. Periprocedural technical complications occurred in 7/59 treatments (11.9%; the most frequent technical complication [n = 3] was thrombus formation), which all resolved completely without clinical sequelae. Postprocedural neurologic complications occurred after 4/59 treatments (6.8%; 2 transient ischemic attacks, 1 minor stroke, 1 major stroke), of which only 1 persistent complication was directly related to the procedure (minor stroke in the vascular territory distal to the stent). CONCLUSIONS: The LVIS EVO stent is a safe, feasible device for the treatment of intracranial aneurysms.

Risk factors associated with progressive lacunar strokes and benefit from dual antiplatelet therapy.

BACKGROUND AND PURPOSE: Early neurological deterioration (END) occurs in 20%-30% of patients with lacunar stroke and challenges their clinical management. This retrospective cohort study analyzed clinical and neuroimaging risk factors predicting the occurrence of END, the functional outcome after END and potential benefit from dual antiplatelet therapy (DAPT) in patients with lacunar strokes. METHODS: Factors associated with END and benefit from DAPT were retrospectively analyzed in 308 patients with lacunar stroke symptoms and detected lacunar infarction by magnetic resonance imaging. END was defined by deterioration of ≥3 total National Institutes of Health Stroke Scale (NIHSS) points, ≥2 NIHSS points for limb paresis or documented deterioration within 5 days after admission. Patients were treated with DAPT according to in-house standards. The primary efficacy end-point for functional outcome was fulfilled if NIHSS at discharge improved after END at least to the score at admission. RESULTS: Male gender [odds ratio (OR) 2.08; 95% confidence interval (CI) 1.09-4.00], higher age (OR = 1.65 per 10 years; 95% CI 1.18-2.31), motor paresis (OR = 18.89, 95% CI 4.66-76.57) and infarction of the internal capsule or basal ganglia (OR = 3.58, 95% CI 1.26-10.14) were associated with an increased risk for END. A larger diameter of infarction (OR = 0.85, 95% CI 0.76-0.95), more microangiopathic lesions (OR = 0.75, 95% CI 0.57-0.99) and pontine localization (OR = 0.29, 95% CI 0.12-0.65) were factors associated with unfavorable functional outcome after END occurred. Localization in the internal capsule or basal ganglia was identified as a significant predictive factor for a benefit from DAPT after END. CONCLUSIONS: Identified clinical and neuroimaging factors predicting END occurrence, functional outcome after END and potential benefit from DAPT might improve the clinical management of patients with lacunar strokes.

The Influence of Angioarchitectural Features on the Success of Endovascular Embolization of Cranial Dural Arteriovenous Fistulas with Onyx.

BACKGROUND AND PURPOSE: Endovascular embolization can be an effective treatment for cranial dural arteriovenous fistulas. However, a considerable number of dural arteriovenous fistulas still cannot be treated sufficiently. The purpose of this study was to report our single-center experience of endovascular embolization of dural arteriovenous fistulas with Onyx, including the investigation of the influence of angioarchitectural features on the treatment success. MATERIALS AND METHODS: Clinical data, angioarchitectural features, complications, treatment success (defined as complete symptom remission for low-grade dural arteriovenous fistulas and complete occlusion for high-grade dural arteriovenous fistulas), and occlusion rates were assessed. The influence of various angioarchitectural features (including location, pattern of venous drainage, and quantity and origin of feeding arteries) was investigated using multivariable backward logistic regression. RESULTS: One hundred four patients with 110 dural arteriovenous fistulas were treated in 132 treatment procedures. Treatment success and complete occlusion rates were 81.8% and 90.9%, respectively. After a mean follow-up of 23.6 months, 95.5% of the patients showed complete symptom remission or symptom relief. The overall complication rate was 8.3% (4.5% asymptomatic, 2.3% transient, and 1.5% permanent complications). Logistic regression showed that ≥10 feeding arteries (P = .041) and involvement of the ascending pharyngeal artery (P = .039) significantly lowered the probability of treatment success. Treatment success tended to be lower for low-grade dural arteriovenous fistulas, Cognard type I dural arteriovenous fistulas, and dural arteriovenous fistulas with involvement of dural branches of the internal carotid artery, however without reaching statistical significance in the multivariable model. CONCLUSIONS: The presence of multiple feeding arteries and involvement of the pharyngeal artery negatively influence the treatment success of endovascular embolization of cranial dural arteriovenous fistulas with Onyx.

Clinical Outcome after Thrombectomy in Patients with Stroke with Premorbid Modified Rankin Scale Scores of 3 and 4: A Cohort Study with 136 Patients.

BACKGROUND AND PURPOSE: We aimed to analyze the clinical outcome after mechanical thrombectomy in patients with premorbid mRS 3 and 4 because there are currently no data on this patient group. MATERIALS AND METHODS: Between January 2009 and November 2017, all patients with premorbid mRS 3 or 4 undergoing mechanical thrombectomy due to anterior circulation stroke were selected. Good outcome was defined as a clinical recovery to the status before stroke onset (ie, equal premorbid mRS and mRS at 90 days). In addition, mortality at discharge and at 90 days was analyzed. RESULTS: One hundred thirty-six patients were included, of whom 81.6% presented with premorbid mRS 3; and 18.4%, with premorbid mRS 4; 24.0% of patients with premorbid mRS 4 achieved clinical recovery compared with 20.7% of patients with premorbid mRS 3 (P = .788). However, the proportion of hospital mortality and mortality at 90 days was nonsignificant, but markedly higher in patients with premorbid mRS 4. Multivariate analysis identified low NIHSS scores (OR, 0.92; 95% CI, 0.85-0.99; P = .040), high ASPECTS (OR, 1.45; 95% CI, 1.02-2.16; P = .049), and TICI 2b-3 (OR, 7.11; 95% CI, 1.73-49.90; P = .017) as independent predictors of good outcome. CONCLUSIONS: Good outcome in patients with premorbid mRS 3 and 4 is less frequent compared with premorbid mRS 0-2. Nevertheless, about 20% of the patients return to their premorbid mRS, which may justify endovascular treatment. The most important predictor of good outcome is successful recanalization.

Value of Contrast-Enhanced MRA versus Time-of-Flight MRA in Acute Ischemic Stroke MRI.

BACKGROUND AND PURPOSE: Vessel imaging in acute ischemic stroke is essential to select patients with large-vessel occlusion for mechanical thrombectomy. Our aim was to compare the diagnostic accuracy of time-of-flight MR angiography and contrast-enhanced MR angiography for identification of vessel occlusion and collateral status in acute ischemic stroke. MATERIALS AND METHODS: One hundred twenty-three patients with stroke with large-vessel occlusion before thrombectomy were included in this retrospective study. Before thrombectomy, 3T MR imaging, including conventional 3D TOF-MRA of the intracranial arteries and contrast-enhanced MRA of intra- and extracranial arteries, was performed. Both techniques were assessed independently by 2 neuroradiologists for location of the occlusion, imaging quality, and collateral status. Findings were compared, with subsequent DSA as the reference standard. RESULTS: Both techniques had good interrater agreement of κ = 0.74 (95% CI, 0.66-0.83) for TOF-MRA and κ = 0.72 (95% CI, 0.63-0.80) for contrast-enhanced MRA. Occlusion localization differed significantly on TOF-MRA compared with DSA (P < .001), while no significant difference was observed between DSA and contrast-enhanced MRA (P = .75). Assessment of collaterals showed very good agreement between contrast-enhanced MRA and DSA (94.9% with P = .25), but only fair agreement between TOF-MRA and DSA (23.2% with P < .001). CONCLUSIONS: Contrast-enhanced MRA offers better diagnostic accuracy than TOF-MRA in acute ischemic stroke. Contrast-enhanced MRA was superior in localizing vessel occlusion within a shorter acquisition time while providing a larger coverage, including extracranial vessels, and a more accurate assessment of collateral status. These results support inclusion of contrast-enhanced MRA in acute stroke MR imaging, perhaps making TOF-MRA superfluous.

Endovascular Treatment of Dural Arteriovenous Fistulas Using Transarterial Liquid Embolization in Combination with Transvenous Balloon-Assisted Protection of the Venous Sinus.

BACKGROUND AND PURPOSE: Sinus-preserving endovascular embolization was described as a promising treatment technique for dural arteriovenous fistulas. Our aim was to report our single-center experience in patients with dural arteriovenous fistulas who were treated with transarterial liquid embolization in combination with transvenous balloon-assisted protection of the affected venous sinus. MATERIALS AND METHODS: A retrospective analysis of a prospectively collected data base was performed. Demographic and clinical data, angiographic features of the dural arteriovenous fistulas, procedural parameters, complications, treatment success, follow-up imaging, and clinical outcome were assessed. RESULTS: Twenty-two patients were treated in 25 procedures. All patients were symptomatic, of whom 81.8% presented with tinnitus; 9.1%, with ocular symptoms; and 9.1%, with headache. Most fistulas were located at the transverse and/or sigmoid sinus. The most frequent fistula type was Cognard IIa+b (40.9%), followed by Cognard I (31.8%) and Cognard IIa (27.3%)/Borden I (59.1%), followed by Borden II (40.9%). The affected sinus could be preserved in all except for 1 patient in whom it was sacrificed in a second treatment procedure by coil embolization. The overall complete occlusion rate was 86.4%. The overall complication rate was 20%, with transient and permanent morbidity and mortality of 8%, 0%, and 0%, respectively. After a mean follow-up of 18 months, most patients (68.2%) achieved complete symptom remission, 27.3% showed symptom relief, and 4.6% had stable symptoms. CONCLUSIONS: Transarterial liquid embolization of dural arteriovenous fistulas in combination with transvenous balloon-assisted protection of the venous sinus is feasible and safe and offers high rates of occlusion and of symptom remission.

The pCONus Device in Treatment of Wide-necked Aneurysms : Technical and Midterm Clinical and Angiographic Results.

PURPOSE: A variety of devices for treatment of wide-necked bifurcation aneurysms are emerging. Here we report our results using the new pCONus device with special emphasis on the morphological and anatomical requirements for successful implantation. METHODS: In this study we treated 21 patients with 22 aneurysms by endovascular interventions. After providing informed consent, patients were included according to the following criteria: aneurysm dome to neck ratio <2 or neck diameter >4 mm. The primary end points for clinical safety were the absence of death, absence of major or minor stroke and absence of transient ischemic attack. RESULTS: A total of 22 aneurysms in 21 patients were treated with pCONus-assisted coiling. In 19 patients harboring 20 aneurysms the implantation of the device was successful and these aneurysms showed an adequate occlusion after 6 months in 95 %. The complication rate was low (5 %) with one case of minor neurological stroke. Analysis of the data showed that the difference in aneurysm angulation between successful (mean 45°) and failed implantations (mean 71.5°) was highly significant. CONCLUSION: Use of the pCONus device and coiling in wide-necked bifurcation aneurysms is safe and provides good occlusion rates but might be limited by the angulation between the aneurysm and the parent vessel.

First Experiences with the New Enterprise2® Stent.

INTRODUCTION: Stent-assisted coiling of wide-necked intracranial aneurysms has become an established treatment and has significantly benefited from the introduction of compliant, self-expanding devices, such as the Enterprise VRD (EP-VRD). We report our experiences with the successor model, the Enterprise2 (EP2) stent in stent-assisted coiling as well as in the treatment of atherosclerotic stenosis. MATERIALS AND METHODS: In 11 consecutive patients 12 EP2 were used to treat 9 intracranial aneurysms and 2 stenoses. RESULTS: All stents could easily be delivered including partial or complete recapturing when necessary. In two cases with sharp angled curves in the carotid siphon there was kinking and flattening of the stent resulting in incomplete wall apposition of the stent. Moreover, when vascular anatomy showed curves with angles >50° it was regularly observed that the proximal stent markers were asymmetrically arranged along the vessel circumference without influence on the stent apposition. Both findings could be reproduced in a silicone flow model. CONCLUSION: The EP2 performed well in our small patient cohort; however, above a critical acute angle there may be incomplete wall apposition of the stent.

e-ASPECTS Correlates with and Is Predictive of Outcome after Mechanical Thrombectomy.

BACKGROUND AND PURPOSE: The e-ASPECTS software is a tool for the automated use of ASPECTS. Our aim was to analyze whether baseline e-ASPECT scores correlate with outcome after mechanical thrombectomy. MATERIALS AND METHODS: Patients with ischemic strokes in the anterior circulation who were admitted between 2010 and 2015, diagnosed by CT, and received mechanical thrombectomy were included. The ASPECTS on baseline CT was scored by e-ASPECTS and 3 expert raters, and interclass correlation coefficients were calculated. The e-ASPECTS was correlated with functional outcome (modified Rankin Scale) at 3 months by using the Spearman rank correlation coefficient. Unfavorable outcome was defined as mRS 4-6 at 3 months, and a poor scan was defined as e-ASPECTS 0-5. RESULTS: Two hundred twenty patients were included, and 147 (67%) were treated with bridging protocols. The median e-ASPECTS was 9 (interquartile range, 8-10). Intraclass correlation coefficients between e-ASPECTS and raters were 0.72, 0.74, and 0.76 (all, P < .001). e-ASPECTS (Spearman rank correlation coefficient = -0.15, P = .027) correlated with mRS at 3 months. Patients with unfavorable outcome had lower e-ASPECTS (median, 8; interquartile range, 7-10 versus median, 9; interquartile range, 8-10; P = .014). Sixteen patients (7.4%) had a poor scan, which was associated with unfavorable outcome (OR, 13.6; 95% CI, 1.8-104). Independent predictors of unfavorable outcome were e-ASPECTS (OR, 0.79; 95% CI, 0.63-0.99), blood sugar (OR, 1.01; 95% CI, 1.004-1.02), atrial fibrillation (OR, 2.64; 95% CI, 1.22-5.69), premorbid mRS (OR, 1.77; 95% CI, 1.21-2.58), NIHSS (OR, 1.11; 95% CI, 1.04-1.19), general anesthesia (OR, 0.24; 95% CI, 0.07-0.84), failed recanalization (OR, 8.47; 95% CI, 3.5-20.2), and symptomatic intracerebral hemorrhage (OR, 25.8; 95% CI, 2.5-268). CONCLUSIONS: The e-ASPECTS correlated with mRS at 3 months and was predictive of unfavorable outcome after mechanical thrombectomy, but further studies in patients with poor scan are needed.

Correlation of Thrombectomy Maneuver Count with Recanalization Success and Clinical Outcome in Patients with Ischemic Stroke.

BACKGROUND AND PURPOSE: In the treatment of acute thromboembolic stroke, the effectiveness and success of thrombus removal when using stent retrievers is variable. In this study, we analyzed the correlation of thrombectomy maneuver count with a good clinical outcome and recanalization success. MATERIALS AND METHODS: One hundred and four patients with acute occlusion of the middle cerebral artery or the terminal internal carotid artery who were treated with thrombectomy were included in this retrospective study. A good clinical outcome was defined as a 90-day mRS of ≤2, and successful recanalization was defined as TICI 2b-3. RESULTS: The maneuver count ranged between 1-10, with a median of 2. Multivariate logistic regression analyses identified an increasing number of thrombectomy maneuvers as an independent predictor of poor outcome (adjusted OR, 0.59; 95% CI, 0.38-0.87; P = .011) and unsuccessful recanalization (adjusted OR, 0.48; 95% CI, 0.32-0.66; P < .001). A good outcome was significantly more likely if finished within 2 maneuvers compared with 3 or 4 maneuvers, or even more than 4 maneuvers (P < .001). CONCLUSIONS: An increasing maneuver count correlates strongly with a decreasing probability of both good outcome and recanalization. The probability of successful recanalization decreases below 50% if not achieved within 5 thrombectomy maneuvers. Patients who are recanalized within 2 maneuvers have the best chance of achieving a good clinical outcome.

Minor Stroke Syndromes in Large-Vessel Occlusions: Mechanical Thrombectomy or Thrombolysis Only?

While mechanical thrombectomy for large-vessel occlusions is now an evidence-based treatment, its efficacy and safety in minor stroke syndromes (NIHSS ≤ 5) is not proved. We identified, in our prospective data base, 378 patients with minor strokes in the anterior circulation; 54 (14.2%) of these had proved large-vessel occlusions. Eight of 54 (14.8%) were immediately treated with mechanical thrombectomy, 6/54 (11.1%) after early neurologic deterioration, and the rest were treated with standard thrombolysis only. Rates of successful recanalization were similar between the 2 mechanical thrombectomy groups (75% versus 100%). Rates of excellent outcome (modified Rankin Scale 0-1) were higher in patients with immediate thrombectomy (75%) compared with patients with delayed thrombectomy (33.3%) and thrombolysis only (55%). No symptomatic intracranial hemorrhage occurred in either group. These descriptive data are encouraging, and further analysis of large registries or even randomized controlled trials in this patient subgroup should be performed.

Clinical Outcome After Mechanical Thrombectomy in Non-elderly Patients with Acute Ischemic Stroke in the Anterior Circulation: Primary Admission Versus Patients Referred from Remote Hospitals.

BACKGROUND AND PURPOSE: Stroke networks have been installed to increase access to advanced stroke specific treatments like mechanical thrombectomy (MT). This concept often requires patients to be transferred to a comprehensive stroke center (CSC) offering MT. Do patient referral, transportation, and logistic effort translate into clinical outcomes comparable to patients admitted primarily to the CSC? MATERIAL AND METHODS: We categorized 112 patients with acute ischemic stroke in the anterior circulation, who received MT at our institution, into primary admissions (A) and referrals from either local (B) or regional (C) hospitals, assessed the clinical outcome, and tested the impact of distance and delay of transportation from the referring remote hospital. RESULTS: The median time from symptom onset to initial CT was similar in all groups (p = 0,939). Patients who were transferred to the CSC had significantly increasing median time between initial CT and MT (in minutes (interquartile range [IQR]); A: 83 [68-120]; B: 174 [159-208]; C: 220 [181-235]; p < 0.001) and median time between onset to MT (in minutes [IQR]; A: 178 [150-210]; B: 274 [238-349]; C: 293 [256-329]; p < 0.001). After 90 days of MT there was no significant difference in clinical outcome (modified Rankin Scale ≤ 2) between primary admitted and referred patients (p = 0.502). CONCLUSION: Clinical outcome in patients who received MT after transfer from either local or regional remote hospitals was not significantly worse than in patients primarily admitted to the CSC. In the event of an acute ischemic stroke patients living in urban or rural areas should, despite a possible delay, have access to MT.

Endovascular Stroke Treatment of Nonagenarians.

BACKGROUND AND PURPOSE: Although endovascular treatment has become a standard therapy in patients with acute stroke, the benefit for very old patients remains uncertain. The purpose of this study was the evaluation of procedural and outcome data of patients ≥90 years undergoing endovascular stroke treatment. MATERIALS AND METHODS: We retrospectively analyzed prospectively collected data of patients ≥90 years in whom endovascular stroke treatment was performed between January 2011 and January 2016. Recanalization was assessed according to the TICI score. The clinical condition was evaluated on admission (NIHSS, prestroke mRS), at discharge (NIHSS), and after 3 months (mRS). RESULTS: Twenty-nine patients met the inclusion criteria for this analysis. The median prestroke mRS was 2. Successful recanalization (TICI ≥ 2b) was achieved in 22 patients (75.9%). In 9 patients, an NIHSS improvement ≥ 10 points was noted between admission and discharge. After 3 months, 17.2% of the patients had an mRS of 0-2 or exhibited prestroke mRS, and 24.1% achieved mRS 0-3. Mortality rate was 44.8%. There was only 1 minor procedure-related complication (small SAH without clinical sequelae). CONCLUSIONS: Despite high mortality rates and only moderate overall outcome, 17.2% of the patients achieved mRS 0-2 or prestroke mRS, and no serious procedure-related complications occurred. Therefore, very high age should not per se be an exclusion criterion for endovascular stroke treatment.

Mechanical Thrombectomy in Patients with Acute Ischemic Stroke and Lower NIHSS Scores: Recanalization Rates, Periprocedural Complications, and Clinical Outcome.

BACKGROUND AND PURPOSE: Mechanical thrombectomy, in addition to intravenous thrombolysis, has become standard in acute ischemic stroke treatment in patients with large-vessel occlusion in the anterior circulation. However, previous randomized controlled stroke trials were not focused on patients with mild-to-moderate symptoms. Thus, there are limited data for patient selection, prediction of clinical outcome, and occurrence of complications in this patient population. The purpose of this analysis was to assess clinical and interventional data in patients treated with mechanical thrombectomy in case of ischemic stroke with mild-to-moderate symptoms. MATERIALS AND METHODS: We performed a retrospective analysis of a prospectively collected stroke data base. Inclusion criteria were anterior circulation ischemic stroke treated with mechanical thrombectomy at our institution between September 2010 and October 2015 with an NIHSS score of ≤8. RESULTS: Of 484 patients, we identified 33 (6.8%) with the following characteristics: median NIHSS = 5 (interquartile range, 4-7), median onset-to-groin puncture time = 320 minutes (interquartile range, 237-528 minutes). Recanalization (TICI = 2b-3) was achieved in 26 (78.7%) patients. Two cases of symptomatic intracranial hemorrhage were observed. Favorable (mRS 0-2) and moderate (mRS 0-3) clinical outcome at 90 days was achieved in 21 (63.6%) and 30 (90.9%) patients, respectively. CONCLUSIONS: The clinical outcome of patients undergoing mechanical thrombectomy for acute ischemic stroke with mild stroke due to large-vessel occlusion appears to be predominately favorable, even in a prolonged time window. However, although infrequent, angiographic complications could impair clinical outcome. Future randomized controlled trials should assess the benefit compared with the best medical treatment.

Frequency and temporal profile of recanalization after cerebral vein and sinus thrombosis.

BACKGROUND AND PURPOSE: The temporal course of recanalization and its association with clinical outcome were analysed in our patients with cerebral sinus and/or venous thrombosis (CSVT) and follow-up magnetic resonance imaging (MRI). METHODS: Between January 1998 and September 2014 all patients from our institutions with CSVT were systematically analysed. Baseline data, treatment characteristics and follow-up MRI were retrospectively recorded. The status of recanalization was assessed as complete (CRec), partial (PRec) or failed recanalization. Clinical follow-up was measured with the modified Rankin Scale. Excellent outcome was defined as modified Rankin Scale 0-1. RESULTS: Ninety-nine patients were identified; 97% of these patients were treated with oral anticoagulation (OAC) and the median (min-max) time of OAC was 7 months (1-84). CRec was achieved in 57.6% (57/99), PRec in 29.3% (29/99) and only 13 (13.1%) patients did not recanalize. The median (min-max) time to PRec was 4 months (0.25-14) and to CRec 6 months (2-34). Median time to last clinical follow-up was 8 months (1-88); 91.8% (89/99) had an excellent outcome at last clinical follow-up and only 2.1% (2/99) died. Only thrombosis of the superior sagittal sinus was independently associated with successful recanalization (odds ratio 16, 95% confidence interval 2-138). No severe haemorrhagic complications and no recurrence of CSVT occurred within clinical follow-up. No association of outcome and recanalization status was found. CONCLUSIONS: The recanalization rate of CSVT under OAC was high and the median time to CRec was 6 months. Thrombosis of the superior sagittal sinus is a positive predictor of recanalization. Outcome in this cohort was excellent but no significant association of outcome and recanalization status was found.