Complete recanalization predicts favorable outcome in patients with distal M2-M3 middle cerebral artery occlusions following endovascular thrombectomy.

BACKGROUND: - scanty articles illustrate the prognostic factors for favorable outcome after endovascular thrombectomy (EVT) in distal vessel occlusion (DMVO). Moreover, the current literature is diversified; conglomerating both primary, secondary, and anterior, posterior circulations embolic strokes in the same shell. PURPOSE: to identify the association between complete reperfusion and favorable outcome following EVT for DMVO in the middle cerebral artery (MCA) territory. METHODS: -we performed a retrospective analysis of prospectively maintained EVT registries at two comprehensive stroke centers between January 2015 and December 2019 for consecutive stroke patients with MCA-DMVO. DMVO was defined as an occlusion of distal M2 and M3 segments of the MCA. Only patients with primary isolated occlusions were included. A multivariate logistic regression was utilized to identify clinical and procedural-related factors associated with the 90-day favorable clinical outcome [defined as modified Rankin score (mRS) 0-2] after EVT. RESULTS: -Out of 1823 within the registries; 66 patients (median age was 72 (60-78) and 59% were males) with primary isolated DMVO of the MCA were eligible for inclusion in the current study. Complete reperfusion was achieved in 56% (37/66) of the patients with no difference among the reperfusion strategies while the favorable outcome was observed in 68% (45/66). In the multivariate analysis, final complete reperfusion [modified Thrombolysis In Cerebral Infarction (mTICI) score 2c-3] was significantly associated with favorable outcome [aOR=7.69; (95% CI 1.73-34.17); p=.01], while higher baseline NIHSS score [aOR=0.82; (95% CI 0.69-0.98); p=.03] and increased imaging to puncture interval [aOR=0.99; (95% CI 0.98, 1.00); p=.01] decreased the probability of the favorable outcome. CONCLUSION: according to our results, complete reperfusion was the most significant predictor of the favorable outcome, while higher baseline NIHSS and longer imaging to puncture interval decreased the probability of the favorable outcome.

Diagnostic Accuracy of Non-Contrast-Enhanced Time-Resolved MR Angiography to Assess Angioarchitectural Classification Features of Brain Arteriovenous Malformations.

This study aims to assess the diagnostic accuracy of non-contrast-enhanced 4D MR angiography (NCE-4D-MRA) compared to contrast-enhanced 4D MR angiography (CE-4D-MRA) for the detection and angioarchitectural characterisation of brain arteriovenous malformations (bAVMs). Utilising a retrospective design, we examined 54 MRA pairs from 43 patients with bAVMs, using digital subtraction angiography (DSA) as the reference standard. Both NCE-4D-MRA and CE-4D-MRA were performed using a 3-T MR imaging system. The primary objectives were to evaluate the diagnostic performance of NCE-4D-MRA against CE-4D-MRA and DSA and to assess concordance between imaging modalities in grading bAVMs according to four main scales: Spetzler-Martin, Buffalo, AVM embocure score (AVMES), and R2eDAVM. Our results demonstrated that NCE-4D-MRA had a higher accuracy and specificity compared to CE-4D-MRA (0.85 vs. 0.83 and 95% vs. 85%, respectively) and similar agreement, with DSA detecting shunts in bAVMs or residuals. Concordance in grading bAVMs was substantial between NCE-4D-MRA and DSA, particularly for the Spetzler-Martin and Buffalo scales, with CE-4D-MRA showing slightly higher kappa values for interobserver agreement. The study highlights the potential of NCE-4D-MRA as a diagnostic tool for bAVMs, offering comparable accuracy to CE-4D-MRA while avoiding the risks associated with gadolinium-based contrast agents. The safety profile of imaging techniques is a significant concern in the long-term follow up of bAVMs, and further prospective research should focus on NCE-4D-MRA protocol improvement for clinical use.

Frontline thrombectomy strategy and outcome in acute basilar artery occlusion.

BACKGROUND: Novel thrombectomy strategies emanate expeditiously day-by-day counting on access system, clot retriever device, proximity to and integration with the thrombus, and microcatheter disengagement. Nonetheless, the relationship between native thrombectomy strategies and revascularization success remains to be evaluated in basilar artery occlusion (BAO). PURPOSE: To compare the safety and efficacy profile of key frontline thrombectomy strategies in BAO. METHODS: Retrospective analyses of prospectively maintained stroke registries at two comprehensive stroke centers were performed between January 2015 and December 2019. Patients with BAO selected after MR imaging were categorized into three groups based on the frontline thrombectomy strategy (contact aspiration (CA), stent retriever (SR), or combined (SR+CA)). Patients who experienced failure of clot retrieval followed by an interchanging strategy were categorized as a fourth (switch) group. Clinicoradiological features and procedural variables were compared. The primary outcome measure was the rate of complete revascularization (modified Thrombolysis in Cerebral Infarction (mTICI) grade 2c-3). Favorable outcome was defined as a 90 day modified Rankin Scale score of 0-2. RESULTS: Of 1823 patients, we included 128 (33 underwent CA, 35 SR, 35 SR +CA, and 25 switch techniques). Complete revascularization was achieved in 83/140 (59%) primarily analyzed patients. SR +CA was associated with higher odds of complete revascularization (adjusted OR 3.04, 95% CI 1.077 to 8.593, p=0.04) which was an independent predictor of favorable outcome (adjusted OR 2.73. 95% CI 1.152 to 6.458, p=0.02). No significant differences were observed for symptomatic intracranial hemorrhage, functional outcome, or mortality rate. CONCLUSION: Among BAO patients, the combined technique effectively contributed to complete revascularization that showed a 90 day favorable outcome with an equivalent complication rate after thrombectomy.

Outcomes Following Mechanical Thrombectomy in Different Etiological Subtypes of Acute Basilar Artery Occlusion : Stroke Etiology and Outcome after EVT in BAO.

BACKGROUND AND PURPOSE: Vertebrobasilar occlusion stroke (VBOS) is innately associated with high morbimortality despite advances in endovascular thrombectomy (EVT). Nonetheless, notable outcome dissimilarities exist between angiographically categorized stroke subtypes. We aim to evaluate potential differences concerning clinical angiographic outcomes among etiological subtypes of VBOS based on the Trial of Org 10172 in Acute Stroke Treatment (TOAST) criteria. METHODS: We retrospectively reviewed prospective EVT databases at two tertiary care stroke centers for consecutive patients with VBOS who had preinterventional MRI and underwent EVT from January 2015 to December 2019. We identified three groups: large artery atherosclerosis (LAA), cardioembolic stroke (CES), and embolic stroke of undetermined source (ESUS). The primary endpoints were the rates of poor outcome (identified as 90-day modified Rankin scale score of 3-6) and mortality, while the secondary endpoint included the rates of incomplete reperfusion (identified as modified treatment in cerebral infarction scale mTICI 0-2b), and periprocedural symptomatic intracranial hemorrhage. We evaluated the association between the etiology and clinical angiographic outcomes through stepwise logistic regression analysis. RESULTS: Out of 1823 patients, 139 (91 men; median age, 69 (61-76) years) with VBOS were qualified for the final analysis with incidence as follows: LAA (41%, n = 57), CES (35%, n = 48), and ESUS (24%, n = 34). Overall, incomplete reperfusion was realized in 41% (57/139) of the patients, a poor outcome in 65% (90/139), and mortality in 40% (55/139). Longer puncture to reperfusion interval (aOR 1.0182 [95% CI: 1.008-1.029]; p < 0.001) and utilization of combined aspiration-retriever technique (aOR 0.1998 [95% CI: 0.066-0.604]; p = 0.004) were associated with a greater likelihood of incomplete reperfusion (mTICI 0-2b) irrespective of the stroke etiology. After adjustment for confounding factors in the regression analysis, ESUS was an independent predictor of poor outcome (aOR 5.315 [95% CI: 1.646-17.163]; p = 0.005) and mortality (aOR 4.667 [95% CI: 1.883-11.564]; p < 0.001) at 90 days following EVT. CONCLUSION: The functional outcome following EVT for VBOS might depend on stroke etiology. According to our results, ESUS seems to be associated with the worst outcome, which needs further investigation to tailor the appropriate therapeutic plan.

Model-Based Iterative Reconstruction (MBIR) for ASPECT Scoring in Acute Stroke Patients Selection: Comparison to rCBV and Follow-Up Imaging.

BACKGROUND: To compare a model-based iterative reconstruction (MBIR) versus a hybrid iterative reconstruction (HIR) for initial and final Alberta Stroke Program Early Ct Score (ASPECT) scoring in acute ischemic stroke (AIS). We hypothesized that MBIR designed for brain computed tomography (CT) could perform better than HIR for ASPECT scoring. METHODS: Among patients who had undergone CT perfusion for AIS between April 2018 and October 2019 with a follow-up imaging within 7 days, we designed a cohort of representative ASPECTS. Two readers assessed regional-cerebral-blood-volume-ASPECT (rCBV-ASPECTS) on the initial exam and final-ASPECTS on the follow-up non-contrast-CT (NCCT) in consensus. Four readers performed independently MBIR and HIR ASPECT scoring on baseline NCCT. RESULTS: In total, 294 hemispheres from 147 participants (average age of 69.59 ± 15.63 SD) were analyzed. Overall raters' agreement between rCBV-map and MBIR and HIR ranged from moderate to moderate (κ = 0.54 to κ = 0.57) with HIR and moderate to substantial (κ = 0.52 to κ = 0.74) with MBIR. Overall raters' agreement between follow-up imaging and HIR/MBIR ranged from moderate to moderate (κ = 0.55 to κ = 0.59) with HIR and moderate to almost perfect (κ = 0.48 to κ = 0.82) with MBIR. CONCLUSIONS: ASPECT scoring with MBIR more closely matched with initial and final infarct extent than classical HIR NCCT reconstruction.

Safety and Efficacy of Cangrelor Among Three Antiplatelet Regimens During Stent-Assisted Endovascular Treatment of Unruptured Intracranial Aneurysm: A Single-Center Retrospective Study.

Introduction: Thromboembolic events represent the most frequent complications of endovascular treatment of unruptured intracranial aneurysm using stent-assisted coilling or flow diverter stents. Dual antiplatelet therapy has become the standard to prevent these but remains unstandardized. We present here a single center experience of 3 standardized antiplatelet regimens during brain aneurysm treatment, while emphasizing the use of the Cangrelor. Method: We retrospectively reviewed data from patients treated using stent-assisted coilling or flow diverter stents from 2016 to 2021. We collected and compared safety and efficacy data within 6 months of three groups of patients corresponding to three antiplatelet standardized regimens: group T with Ticagrelor, with preprocedural preparation; group E with Eptifibatide, injected during procedure; group C with Cangrelor, injected during procedure. Results: Data of 112 patients were analyzed and 76 belonged to group T, 21 to group E, and 15 to group C. Eleven events over the 14 recorded were adjudicated to be related to antiplatelets, their repartition did not differ between the 3 groups (p = 0.43). All symptomatic events (N = 8) were not distributed significantly differently between the 3 groups (p = 0.11) and asymptomatic events were also balanced (p = 1.00). Of these, 6 subjects had a change in the mRS score at 3-6 months. Thrombo-embolic events represented the most encountered events in the sample: 2 acute ischemic strokes were recorded in group E and 1 in group T; 1 transient ischemic stroke was noted in group E; 4 silent infarcts were found on control MRI (2 belonged to group T, 1 to group E and 1 to group C). Among 3 intracranial bleeding events, 1 was symptomatic in group C, 2 were asymptomatic in group T. On the control evaluation performed at 6 months, there was no significant difference on aneurysmal occlusion (p = 0.67). Conclusion: This single-center retrospective study compared 3 antiplatelet regimens, finding no significant difference in the safety and efficacy in the context of endovascular treatments of unruptured aneurysm using stent or flow diverters. This study adds data for the Cangrelor use and suggests its usefulness in the field of neuro-endovascular intervention. Randomized controlled studies are warranted to confirm these results.

Volume variation may be a relevant metric in the study of aneurysm pulsatility: a study using ECG-gated 4D-CTA (PULSAN).

​BACKGROUND AND PURPOSE: Intracranial aneurysms are a frequently occurring disease, with an estimated prevalence of 2-5% in the general population. They usually remain silent until rupture occurs, with a mortality rate of 35-50% and a high rate of morbidity, including long-term disability. However, preventative treatments have their own risk of complications and morbi-mortality rates, including stroke and hemorrhage. ECG-gated four-dimensional CT angiography (4D-CTA) allows the acquisition of time-resolved three-dimensional reconstructions. The aim of our study was to evaluate different intracranial aneurysm metrics over the cardiac cycle using ECG-gated 4D-CTA. ​MATERIALS AND METHODS: ECG-gated 4D-CTA datasets were acquired in patients presenting with intracranial aneurysms. Seven aneurysm metrics, including aneurysm height, aneurysm length, ostium width, aspect ratio, ostium area, volume, and volume-to-ostium ratio, were analysed over different cardiac phases. Intra-reader agreement, inter-reader agreement, and inter-cycle agreement were calculated through the intraclass correlation coefficient. ​RESULTS: Twenty-one aneurysms from 11 patients were considered for inclusion. Post-processing failed for three aneurysms, and 18 aneurysms were finally analysed. There was good intra-reader agreement for each metric (ICC >0.9). Agreements among three consecutive cardiac cycles were calculated for six aneurysms and were especially good for the volume metric (ICC >0.9). Volume variation appears to be the most relevant metric and seems especially perceptible for aneurysms larger than 5 mm. ​CONCLUSIONS: Quantification of aneurysm volume changes during the cardiac cycle seems quantitatively possible and reproducible, especially for aneurysms larger than 5 mm. Further studies need to be conducted to validate this parameter for intracranial aneurysm assessment.

Four-dimensional computed tomography angiography analysis of internal carotid arteries opacification at the skull base to detect delayed cerebral ischemia: a feasibility study.

PURPOSE: Delayed cerebral ischemia represents a significant cause of poor functional outcome for patients with vasospasm after subarachnoid hemorrhage. We investigated whether delayed cerebral ischemia could be detected by the arterial opacification of internal carotid artery at the level of the skull base. METHODS: In this exploratory, nested retrospective cohort diagnostic accuracy study, patients with clinical and/or transcranial Doppler suspicion of vasospasm who underwent four-dimensional computed tomography angiography were included. They were split into two groups for the main endpoint analysis, according to the actually adopted morphological (cerebral infarction) and clinical criteria (neurologic deterioration) of delayed cerebral ischemia. Opacification with a temporal resolution of 0.15 s of both internal carotid arteries at the skull base level was obtained through a semi-automated segmentation method based on skeletonization, and analyzed by a wavelet transform (rbio2.2, level 1). The results obtained by k-means clustering were analyzed with regard to the state of delayed cerebral infarction. RESULTS: Over ten patients included and analyzed, five patients presented a delayed cerebral ischemia, two of them in both side. The semi-automated processing and analysis clustered two different types of opacification curves. The obtaining of a nonlinear opacification pattern was associated (p < 0.001) with delayed cerebral ischemia. CONCLUSIONS: The analysis of arterial opacification of internal carotid arteries at skull base by the proposed processing is feasible and leads to cluster two types of opacification that may help to early detect and prevent delayed cerebral ischemia, in particularly when examinations are artifacted by aneurysm treatment materials.