M1 Segment Research Articles

BIOM-08. CDKN2A --AN INDEPENDENT CYCLIN-DEPENDENT KINASE INHIBITOR VARIANT ASSOCIATED WITH MALIGNANCY AND WITH SMALL VESSEL STROKE, AS A POTENTIAL MARKER FOR RISK OF LARGE-VESSEL STROKE COMPLICATING BENIGN TERATOMA

Abstract BACKGROUND Cyclin-dependent kinase inhibitor variants, particularly those of CDKN2A are known to be associated with autosomal dominant Familial Atypical Multiple Mole/Melanoma Syndrome and pancreatic cancer predisposition. These variants are associated with risk of small vessel stroke in African/ African-American populations, and are risk factors for stroke in Nordic populations with hypertension, independent of cardiovascular risk factors. METHODS We performed a case review of a female presenting in late infancy with a central nervous system teratoma, that later was complicated by a right hemispheric middle cerebral artery (MCA)stroke, associated with a CDKN2A germline mutation. RESULTS This 14month old female presented with transient alterations of consciousness and apparent abdominal migraine events with pernicious vomiting. Neuroimaging revealed a right heterogeneous para- suprasellar mass and bilateral complex arachnoid adjacent cysts. She was observed closely for any progression, as the lesion was immediately adjacent to the optic chiasm. One year after presentation, she developed an acute ischemic right middle cerebral artery (MCA) stroke and had radiographic evidence of severe stenosis and decreased flow primarily within the right supra-clinoid internal carotid artery, the M1 segment and portion of the right A1 segment of cerebral vessels, with decreased enhancement and number of vessels in the distal right MCA territory. The vessels did not appear to be compressed by any mass effect. The radiologic appearance was consistent with vasospasm. The patient upon stoke recovery, underwent near- complete resection of the mass with no evidence of disruption of the capsule surrounding it and no vascular infiltration. Pathology revealed the expected teratoma with prominence of pancreatic acinar structures, and molecular evidence of a variant of CDKN2A, which was present in the patient and mother in the germline. CONCLUSION We propose that the imaging evidence of a vasculopathy was related to the genotype at the cyclin- dependent kinase site.

Stop Ischemic Event to the Brain: Screening Risk Factors of Cerebrovascular Stenosis in Coronary Artery Disease Patients.

In this study, we investigated the difference in risk factors between the 2 diseases, aiming to further clarify who needs to do ischemic cerebrovascular disease (ICVD)-related screening among coronary artery disease (CAD) patients. Clinical data of 326 patients with first-episode CAD from June 1, 2017, to July 31, 2020, in the Chinese PLA General Hospital were retrospectively reviewed. Outcomes, including clinical features and laboratory examination, were taken. Features related to ICVD including the extension of intracranial arterial (internal carotid artery intracranial segment, middle cerebral artery M1 segment, anterior cerebral A1 segment, vertebrobasilar artery intracranial segment, posterior cerebral artery P1 segment) and carotid arterial (internal carotid artery extracranial segment, common carotid artery, subclavian artery) stenosis were detected. Risk factors for the occurrence of ICVD in patients with CAD were analyzed. Among patients with the onset of CAD, in comparison of the nonstenosis and stenosis of intracranial artery subgroups, there were statistical differences in the onset age, hypertension, and duration of hypertension as well as the biochemical indicators, including high-density lipoprotein and glycosylated hemoglobin. In addition, statistical differences were detected in the onset age as well as the biochemical indicators, including glycosylated hemoglobin and blood glucose serum protein, along with the difference in the degree of cardiovascular stenosis. The onset age of CAD was shown to serve as a vital risk factor for ICVD. The primary prevention of ICVD in patients with CAD should lay more emphasis on the management of hypertension and diabetes.

Association between procedural time and outcome in unsuccessful mechanical thrombectomy for acute ischemic stroke: analysis from the Italian Registry of Endovascular Treatment in Acute Stroke.

We aim to assess the association between procedural time and outcomes in patients in unsuccessful mechanical thrombectomy (MT) for anterior circulation acute stroke. We conducted a cohort study on prospectively collected data from patients with M1 and/or M2 segment of middle cerebral artery occlusion with a thrombolysis in cerebral infarction 0-1 at the end of procedure. Primary outcome was 90-day poor outcome. Secondary outcomes were early neurological deterioration (END), symptomatic intracranial hemorrhage (sICH) according to ECASS II and sICH according to SITS-MOST. Among 852 patients, after comparing characteristics of favourable and poor outcome groups, logistic regression analysis showed age (OR: 1.04; 95%CI: 1.02-1.05; p < 0.001), previous TIA/stroke (OR: 0.23; 95%CI: 0.12-0.74; p = 0.009), M1 occlusion (OR: 1.69; 95%CI: 1.13-2.50; p = 0.01), baseline NIHSS (OR: 1.01; 95%CI: 1.06-1.13; p < 0.001) and procedural time (OR:1.00; 95% CI: 1.00-1.01; p = 0.003) as independent predictors poor outcome at 90days. Concerning secondary outcomes, logistic regression analysis showed NIHSS (OR:0.96; 95%CI: 0.93-0.99; p = 0.008), general anaesthesia (OR:2.59; 95%CI: 1.52-4.40; p < 0.001), procedural time (OR: 1.00; 95% CI: 1.00-1.01; p = 0.002) and intraprocedural complications (OR: 1.89; 95%CI: 1.02-3.52; p = 0.04) as independent predictors of END. Bridging therapy (OR:2.93; 95%CI: 1.21-7.09; p = 0.017) was associated with sICH per SITS-MOST criteria whereas M1 occlusion (OR: 0.35; 95%CI: 0.18-0.69; p = 0.002), bridging therapy (OR: 2.02; 95%CI: 1.07-3.82; p = 0.03) and intraprocedural complications (OR: 5.55; 95%CI: 2.72-11.31; p < 0.001) were independently associated with sICH per ECASS II criteria. No significant association was found between the number of MT attempts and analyzed outcomes. Regardless of the number of MT attempts and intraprocedural complications, procedural time was associated with poor outcome and END. We suggest a deeper consideration of procedural time when treating anterior circulation occlusions refractory to MT.

Comparing Outcomes of Thrombectomy Versus Intravenous Thrombolysis Based on Middle Cerebral Artery M2 Occlusion Features.

Current evidence provides limited support for the superiority of endovascular thrombectomy (EVT) in patients with M2 segment middle cerebral artery occlusion. We aim to investigate whether imaging features of M2 segment occlusion impact the effectiveness of EVT. We conducted a retrospective cohort study from January 2017 to January 2022, drawing data from the CASE II registry (Computer-Based Online Database of Acute Stroke Patients for Stroke Management Quality Evaluation), which specifically documented patients with acute ischemic stroke presenting with M2 segment occlusion undergoing reperfusion therapy. Patients were stratified into the intravenous thrombolysis (IVT) group (IVT alone) and EVT group (IVT plus EVT or EVT alone). The primary outcome was a modified Rankin Scale score 0 to 2 at 90 days. Secondary outcomes included additional thresholds and distribution of modified Rankin Scale scores, 24-hour recanalization, early neurological deterioration, and relevant complications during hospitalization. Safety outcomes encompassed intracranial hemorrhagic events at 24 hours and mortality at 90 days. Binary logistic regression analyses with propensity score matching were used. Subgroup analyses were performed based on the anatomic site of occlusion, including right versus left, proximal versus distal, dominant/co-dominant versus nondominant, single versus double/triple branch(es), and anterior versus central/posterior branch. Among 734 patients (43.3% were females; median age, 73 years) with M2 segment occlusion, 342 (46.6%) were in the EVT group. Propensity score matching analysis revealed no statistical difference in the primary outcome (odds ratio, 0.860 [95% CI, 0.611-1.209]; P=0.385) between the EVT group and IVT group. However, EVT was associated with a higher incidence of subarachnoid hemorrhage (odds ratio, 6.655 [95% CI, 1.487-29.788]; P=0.004) and pneumonia (odds ratio, 2.015 [95% CI, 1.364-2.977]; P<0.001). Subgroup analyses indicated that patients in the IVT group achieved better outcomes when presenting with right, distal, or nondominant branch occlusion (Pall interaction<0.05). Our study showed similar efficiency of EVT versus IVT alone in acute M2 segment middle cerebral artery occlusion. This suggested that only specific patient subpopulations might have a potentially higher benefit of EVT over IVT alone. URL: https://clinicaltrials.gov; Unique identifier: NCT04487340.

Intracranial thrombus composition is associated with occlusion location and endovascular treatment outcomes: results from ITACAT multicenter study

BackgroundThe impact of thrombolytics directed towards different thrombus components regarding site of occlusion in combination with mechanical thrombectomy (MT) to achieve endovascular complete recanalization is unclear.MethodsRetrospective analysis of a prospective...

Effect of Endovascular Thrombectomy for Acute Ischemic Stroke on Cognitive Outcomes: A Secondary Analysis of the ESCAPE Trial.

The effect of endovascular therapy (EVT) for large vessel occlusion stroke on cognitive outcomes is not well understood. We evaluated the effect of EVT on cognitive function in the Endovascular Treatment for Small Core and Anterior Circulation Proximal Occlusion With Emphasis on Minimizing CT to Recanalization Times (ESCAPE) trial. Patient data from the ESCAPE randomized trial were analyzed. Cognitive assessments completed at 90 days after stroke were the Montreal Cognitive Assessment (MoCA), the Sunnybrook Neglect Assessment Procedure (SNAP), the Boston Naming Test (BNT), Trail-making test A (Trails A), and Trail-making test B (Trails B). We used logistic regression to evaluate the association between EVT and favorable cognitive outcome on the 5 separate tests, adjusting for demographic and clinical factors. We used generalized estimating equations and ordinal regression to determine the odds of favorable outcome with EVT on global cognition incorporating the 5 tests. We added final infarct volume (FIV) to the models to assess the relationship of FIV with cognitive outcome. The ESCAPE trial included 315 patients, 165 randomized to EVT and 150 randomized to control. There was higher odds of favorable outcome with EVT for MoCA (adjusted odds ratio [aOR] 2.32, 95% CI 1.30-4.16), SNAP (aOR 3.85, 95% CI 2.00-7.45), BNT (aOR 2.33, 95% CI 1.30-4.17), trails A (aOR 3.50, 95% CI 1.93-6.36), and trails B (aOR 2.56, 95% CI 1.46-4.48). There was higher odds of favorable outcome with EVT on global binary (aOR 2.57, 95% CI 1.67-3.94) and ordinal analyses (aOR 2.83, 95% CI 1.68-4.76) of cognitive function. After adding FIV to the models, both FIV and EVT were significantly associated with cognitive outcome. There was a significant correlation between global cognitive performance and mRS at day 90 (r = -0.78, p < 0.001), with the largest reductions in favorable cognitive outcome from mRS score 4 to 5 and from mRS 2 to 3. In this secondary analysis of the ESCAPE trial, EVT was associated with favorable outcome on 5 separate cognitive tests and in global analyses of cognitive benefit. These results provide novel evidence for the effect of EVT on cognition and support the global benefit of treatment with EVT. This study provides Class II evidence that in patients with acute ischemic stroke due to intracranial internal carotid artery (ICA) or M1 segment MCA occlusion, including tandem extracranial ICA occlusions, EVT compared with best medical therapy increased odds of favorable cognitive outcome.

Effect of Drug-Coated Balloon Versus Stent Angioplasty in Patients With Symptomatic Intracranial Atherosclerotic Stenosis.

Drug-coated balloons (DCBs) have exhibited promising results in coronary and peripheral artery diseases, but conclusive evidence is lacking in intracranial vasculature. We assessed the safety and efficacy of DCBs vs stent angioplasty for symptomatic intracranial atherosclerotic stenosis (sICAS) and initially identified patients who might have benefited most from DCB treatment. A single-center, retrospective cohort study was conducted from June 2021 to May 2022 with 154 patients with sICAS divided into 2 treatment groups: a DCB group (with or without remedial stenting, n = 47) and a stent group (n = 107). The treatment outcomes were compared using 1:2 propensity score matching. The primary safety end point was perioperative stroke or mortality, and the primary efficacy end point was the rate of target vessel restenosis at 12 months. The degree of luminal change was analyzed as a subgroup, defined as the difference between the degree of stenosis at follow-up and immediately after intervention. One hundred eighteen patients were enrolled using propensity score matching, with 43 patients in the DCB group and 75 in the stent group. The incidence of perioperative adverse events was 2.3% in the DCB group and 8.0% in the stent group (P = .420). At a median follow-up of 12 months, the incidence of restenosis (11.9% [5/43] vs 28.0% [21/75], P = .045) and the median degree of stenosis (30% [20%, 44%] vs 30% [30%, 70%], P = .009, CI [0-0.01, 0.2]) were significantly lower in the DCB group than in the stent group. DCB angioplasty effectively prevented adverse events in the target vessel area and significantly reduced the degree of luminal change in the M1 segment of the middle cerebral artery (0 [0, 15%] vs 10% [0, 50%], P = .016). DCB angioplasty might be a safe and effective alternative to stent angioplasty to treat sICAS, particularly among patients with M1 segment of the middle cerebral artery stenosis.

Mechanical Thrombectomy in Medium Vessels Occlusion (MeVOs): An Institutional Experience with M2 Divisions of Middle Cerebral Artery.

Mechanical thrombectomy has been established as a safe, standard and effective treatment option for occlusions of the proximal segment of the middle cerebral artery (MCA), as demonstrated in numerous studies. However, performing thrombectomy in the M2 divisions of MCA presents inherent challenges. In this institutional experience, we aim to delineate the recanalisation rates achieved through mechanical thrombectomy in cases involving the M2 segment of the MCA. We conducted a retrospective analysis of patients who underwent thrombectomy due to M2 MCA occlusions in the period from January 2018 to December 2021. Various factors affecting recanalisation rates were assessed. A total of 15 patients with M2 segment occlusions of the middle cerebral artery were included in the study, comprising 11 in the superior division and 4 in the inferior division. The successful recanalisation rate was 72.33%, with notably higher success observed in cases of inferior division occlusion. The primary outcome of our study was the mTICI recanalisation status, categorised as successful recanalisation (mTICI = 2b or mTICI = 3) and unsuccessful recanalisation (mTICI = 1 or mTICI = 2a) and mRS at 6 months. None of the predictors assessed reached statistical significance. Mechanical thrombectomy demonstrates favourable efficacy and recanalisation rates in cases of M2 MCA division occlusion. Notably, inferior division occlusions exhibit a higher likelihood of successful recanalisation.

Correlations between intravascular pressure gradients and cerebral blood flow in patients with symptomatic, medically refractory, anterior circulation artery stenosis: an exploratory study

BackgroundFractional flow reserve is widely used in coronary disease management, with a threshold of 0.80. However, similar thresholds are unclear in functional assessment of intracranial atherosclerotic stenosis (ICAS).ObjectiveTo investigate the...

Super-selective injection of propofol into the intracranial arteries enables Patient's self-evaluation of expected neurological deficit

IntroductionIt is hard to realize the extent of the expected postoperative neurological deficit for patients themselves. The provision of appropriate information can contribute not only to examining surgical indications but also to filling the gap between patient and expert expectations. We hypothesized that propofol infusion into the intracranial arteries (ssWada) could induce focal neurological symptoms with preserved wakefulness, enabling the patients to evaluate the postsurgical risk subjectively. MethodsPresurgical evaluation using ssWada was performed in 28 patients with drug-resistant epilepsy. Based on anatomical knowledge, propofol was super-selectively infused into the intracranial arteries including the M1, M2, and M3 segments of the middle cerebral artery (MCA), A2 segment of the anterior cerebral artery, and P2 segment of the posterior cerebral artery to evaluate the neurological and cognitive symptoms. We retrospectively analyzed a total of 107 infusion trials, including their target vessels, and elicited symptoms of motor weakness, sensory disturbance, language, unilateral hemispatial neglect (UHN), and hemianopsia. We evaluated preserved wakefulness which enabled subjective evaluations of the symptoms and comparison of the subjective experience to the objective findings, besides adverse effects during the procedure. ResultsPreserved wakefulness was found in 97.2% of all trials. Changes in neurological symptoms were positively evaluated for motor weakness in 51.4%, sensory disturbance in 5.6%, language in 48.6%, UHN in 22.4%, and hemianopsia in 32.7%. Six trials elicited seizures. Multivariate analysis showed significant correlations between symptom and infusion site of language and left side, language and MCA branches, motor weakness and A2 or M2 superior division, and hemianopsia and P2. Transient adverse effect was observed in 8 cases with 12 infusion trials (11.2 %). ConclusionThe ssWada could elicit focal neurological symptoms with preserved wakefulness. The methodology enables specific evaluation of risk for cortical resection and subjective evaluation of the expected outcome by the patients.

A Comparative Study of AI-Based Automated and Manual Postprocessing of Head and Neck CT Angiography: An Independent External Validation with Multi-Vendor and Multi-Center Data.

To externally validate the performance of automated postprocessing (AP) on head and neck CT Angiography (CTA) and compare it with manual postprocessing (MP). This retrospective study included head and neck CTA-exams of patients from three tertiary hospitals acquired on CT scanners from five manufacturers. AP was performed by CerebralDoc. The image quality was assessed using Likert scales, and the qualitative and quantitative diagnostic performance of arterial stenosis and aneurysm, postprocessing time, and scanning radiation dose were also evaluated. A total of 250 patients were included. Among these, 55 patients exhibited significant stenosis (≥ 50%), and 33 patients had aneurysms, diagnosed using original CTA datasets and corresponding multiplanar reconstructions as the reference. While the scores of the V4 segment and the edge of the M1 segment on volume rendering (VR), as well as the C4 segment on maximum intensity projection (MIP), were significantly lower with AP compared to MP across vendors (all P < 0.05), most scores in AP demonstrated image quality that was either superior to or comparable with that of MP. Furthermore, the diagnostic performance of AP was either superior to or comparable with that of MP. Moreover, AP also exhibited advantages in terms of postprocessing time and radiation dose when compared to MP (P < 0.001). The AP of CerebralDoc presents clear advantages over MP and holds significant clinical value. However, further optimization is required in the image quality of the V4 and M1 segments on VR as well as the C4 segment on MIP.

Distance to thrombus, ischemic lesion volume and clinical outcome after thrombectomy for M1 middle cerebral artery occlusion.

Stroke resulting from occlusion of the middle cerebral artery (MCA) can have devastating consequences, potentially leading to aloss of independence. This study aimed to investigate the relationship between the distance to the thrombus (DT) and both ischemic lesion volume (ILV) and clinical outcomes. We retrospectively evaluated patients with thromboembolic MCA M1 segment occlusion who underwent neurovascular imaging followed by endovascular thrombectomy (EVT) at two comprehensive stroke centers over a3-year period (2018-2020). Preinterventional computed tomography (CT) or magnetic resonance (MR) angiography was used to measure DT, defined as the distance from the carotid‑T bifurcation to the proximal surface of the M1 occlusion. Postinterventional CT or MR imaging was employed to determine the ILV and clinical outcomes were assessed using the modified Rankin scale (mRS) at 3 months. There were 346 patients evaluated. The median DT was 9.4 mm (interquartile range, IQR 6.0-13.7 mm) and the median ILV was 13.9 ml (IQR 2.2-53.1 ml). After adjustment, an increase in DT was associated with adecrease in odds for a larger ILV (odds ratio, OR 0.96, 95% confidence interval, CI 0.92-0.99, p = 0.041). Through this association, more distal thrombi were associated with good clinical outcome (mRS 0-2; clinical outcome available in 282 patients, p = 0.018). The ILV was inversely associated with better clinical outcome OR 0.52 (95% CI 0.40-0.67). Based on the findings, DT was identified as an independent albeit weak predictor for ILV and clinical outcomes in patients with MCA M1 occlusion who underwent EVT.

Impact of preaneurysmal M1 length in unruptured middle cerebral artery aneurysm: mid-term outcome and single-center experience

ObjectiveThis study was design to investigate the surgical and functional outcome based on the preaneurysmal M1 length for unruptured MCA aneurysm. MethodsAmong 250 consecutive patients with unruptured aneurysms operated in our institution between 2015 and 2017, 72 were MCA aneurysms. Risk factors for IR (i.e., intraoperative rupture) were investigated including age, sex, preaneurysmal M1 length, maximal MCA aneurysm diameter, neck size, aneurysm shape, sphenoid ridge proximation sign. Outcome was measured at discharge, 1 yr and last follow-up. Outcome was compared according to the preaneurysmal M1 length. ResultsAmong 68 patients included, five patients (7.3%) suffered IR. Mean maximal diameter of MCA aneurysm (7.9 mm ± 3.4 vs. 4.5 ± 1.8; p = 0.01) was significantly associated with IR risk. Mean M1 length seemed to be shorter in the IR group although not statistically significant (16.2 mm ± 5.1 vs. 11.5 mm ± 4.8; p = 0.053). Mid-term outcome was favorable for all patients at last follow-up but was worsen in case of short preaneurysmal M1 segment (10.7 mm ± 4.8 vs. 16.4 mm ± 5.3, p = 0.02). Complete aneurysm occlusion was achieved for sixty-nine patients (95.5%) with 6.9% of early postoperative complications. ConclusionsThe microsurgical treatment of unruptured MCA aneurysm was associated with favorable mid-term outcome in all patients and high rates of complete occlusion. Aneurysm size was significantly associated with the intraoperative rupture risk for unruptured MCA aneurysm and patients with a short preaneurysmal M1 segment seemed to have a greater risk of intraoperative rupture although not statistically significant. Short preaneurysmal M1 patients had worsen mid-term outcome.

Assessing donor-recipient arterial pressure dynamics in STA-MCA bypass for moyamoya disease

BackgroundIn bypass surgery for moyamoya disease (MMD), the superficial temporal artery’s (STA) pressure needs to surpass that of the cortical M4 recipient of the middle cerebral artery (MCA), boosting cerebral blood flow into the MCA and enhancing cerebral circulation. This study investigates the STA-MCA arterial pressure parameters and gradients during bypass surgery, aiming to deepen our understanding of hemodynamic shifts pre- and post-operation.MethodsDSA imaging data were prospectively collected from patients diagnosed with bilateral MMD who underwent STA-MCA bypass surgery between 2022 and 2023 and stratified according to the Suzuki stage. The mean arterial pressure (MAP) of the donor and recipient arteries was directly measured during the STA-MCA bypass procedure, and these data were statistically analyzed and evaluated.ResultsAmong 48 MMD patients, Suzuki grading revealed that 43.8% were in early stages (II and III), while 56.2% were in advanced stages (IV, V, and VI). Predominantly, 77.1% presented with ischemic-type MMD and 22.9% with hemorrhagic type. Pre-bypass assessments showed that 62.5% exhibited antegrade blood flow direction, and 37.5% had retrograde. The mean recipient artery pressure was 35.0 ± 2.3 mmHg, with a mean donor-recipient pressure gradient (δP) of 46.4 ± 2.5 mmHg between donor and recipient arteries. Post-bypass, mean recipient artery pressure increased to 73.3 ± 1.6 mmHg. No significant correlation (r = 0.18, P = 0.21) was noted between δP and Suzuki staging.ConclusionOur study elucidated that cerebral blood pressure significantly decreases beyond the moyamoya network at the distal M4 segment. Furthermore, we observed bidirectional flow in MCA territories and a significant positive pressure gradient between the STA and M4 segments. The lack of correlation between Suzuki stages and M4 pressures indicates that angiographic severity may not reflect hemodynamic conditions before surgery, highlighting the need for customized surgical approaches.

Endovascular treatment in Danon disease: a case report

BackgroundDanon disease is a lysosomal storage disorder with X-linked inheritance. The classic triad is severe hypertrophic cardiomyopathy, myopathy, and intellectual disability, with different phenotypes between both genders. Ischemic stroke is an uncommon complication, mostly cardioembolic, related to intraventricular thrombus or atrial fibrillation, among others.Case reportWe report the case of a 14-year-old Caucasian male patient with Danon disease who suffered from an acute ischemic stroke due to occlusion in the M1 segment of the middle cerebral artery. He underwent mechanical thrombectomy, resulting in successful revascularization with satisfactory clinical outcome. We objectified the intraventricular thrombus in the absence of arrhythmic events.ConclusionTo our knowledge, we report the first case of ischemic stroke related to Danon disease treated with endovascular treatment.

The Art of Cerebral Revascularization: An Illustrative Case Series of Bypass Techniques for Complex Intracranial Aneurysms

Complex intracranial aneurysms (CIAs) comprise a subset of lesions with defiant vascular architecture, difficult access, and prior treatment. Surgical management of CIAs is often challenging and demands an assessment on a case-by-case basis. The generational evolution of bypass surgery has offered a long-standing potential for effective cerebral revascularization. Herein, we aim to illustrate a single-center experience treating CIAs. The authors conducted a retrospective analysis of clinical records of patients treated with cerebral revascularization techniques at Hospital Nacional Dos de Mayo, Lima, Peru, during 2018-2022. Relevant data were collected, including patient history, aneurysm features on imaging, preoperative complications, the intraoperative course, aneurysm occlusion rates, bypass patency, neurological function, and postoperative complications. Seventeen patients (70.59% female; median age: 53years) with 17 CIAs (64.7% saccular; 76.5% ruptured) were included. The most common clinical presentation included loss of consciousness (70.6%) and headaches (58.8%). Microsurgical treatment included first-, second-, and third-generation bypass. In 47.1% of cases, an anastomosis between the superficial temporal artery and the M3 segment was predominantly used, followed by an A3-A3 bypass (29.4%), a superficial temporal artery-M2 bypass (17.6%), and an external carotid artery to M2 bypass (5.9%). The intraoperative aneurysm rupture rate was 11.8%. Postoperative complications included ischemia (40%), cerebrospinal fluid fistulas (26.7%), and pneumonia (20%). At hospital discharge, the median Glasgow Coma Scale score was 14 (range: 10-15). At the 6-month follow-up, 82.4% of patients had a modified Rankin Scale score ≤2, bypass patency was present in all cases, and the morbidity rate was 17.6%. CIAs represent a spectrum of defiant vascular lesions with a poor natural history. Bypass surgery offers the potential for definitive treatment. Our case series illustrated the predominant role of cerebral revascularization of CIAs with a critical case-by-case approach to provide optimal outcomes in a limited-resource setting.

EnDovascular Therapy Plus Best Medical Treatment (BMT) Versus BMT Alone for MedIum distal VeSsel Occlusion sTroke (DISTAL): An international, multicentre, randomized-controlled, two-arm, assessor-blinded trial.

Whether endovascular therapy (EVT) in addition to best medical treatment (BMT) in people with acute ischemic stroke (AIS) due to a medium distal vessel occlusion (MDVO) is beneficial remains unclear. To determine if people experiencing an AIS due to an isolated MDVO (defined as the co- or non-dominant M2 segment, the M3 or M4 segment of the middle cerebral artery, the A1, A2, or A3 segment of the anterior cerebral artery or the P1, P2 or P3 segment of the posterior cerebral artery) will have superior outcome if treated with EVT in addition to BMT compared to BMT alone. To randomize 526 participants 1:1 to EVT plus BMT or BMT alone. A multicentre, international, prospective, randomized, open-label, blinded-endpoint (PROBE) superiority trial. The primary efficacy endpoint is the distribution of disability levels on the modified Rankin Scale at 90 days. Secondary clinical efficacy outcomes include normalized change in National Institutes of Health Stroke Scale score from baseline to day 1, cognitive outcome at 90 days, and health-related quality of life at 90 days. Safety outcomes include all serious adverse events, symptomatic intracranial hemorrhage within 24 h, and all-cause mortality up to 90 days. Secondary imaging outcomes include successful reperfusion at end of EVT procedure and recanalization of target artery at 24 h. DISTAL will inform physicians whether EVT in addition to BMT in people with AIS due to a MDVO is more efficacious than BMT alone.

Anatomical Markers Associated With the Presence of Intracranial Aneurysms in Individuals Screened for Aneurysms

Background Hemodynamic stress is linked to the development of intracranial aneurysms (IAs) and may be influenced by anatomic variation of intracranial arteries. We assessed diameters and bifurcation angles of intracranial arteries forming the circle of Willis in a cohort of individuals screened for the presence of IAs. Methods Individuals with and without IAs identified at screening with magnetic resonance angiography were compared. Diameters and bifurcation angles of the following arteries were measured using semiautomatic methods: A1 and A2 segments of the anterior cerebral artery, M1 and M2 segments of the middle cerebral artery, P1 segments of the posterior cerebral artery, posterior communicating artery (Pcom), internal carotid artery, vertebral artery, and basilar artery. We employed univariate general linear models to assess group differences. This included subgroup comparisons between individuals with IAs at specific locations and matched controls, and comparisons on group level between individuals with and without IAs, corrected for age and sex. Results In 94 of the 1049 individuals (9.0%) included, IAs were detected. Individuals with middle cerebral artery IAs had wider ipsilateral M2–M2 bifurcation angles compared with controls (121±25° versus 97±19°; P &lt;0.01). Individuals with anterior communicating artery IAs showed smaller angles for the A1–A2 bifurcation (106±16° versus 120±17°; P = 0.02), while those with Pcom IAs had wider Pcom–C7 bifurcation angles (147±14° versus 127±17°; P = 0.02) and smaller diameters below the ipsilateral internal carotid artery top (2.86±0.36 mm versus 3.10±0.33 mm; P = 0.03) compared with controls. Conclusion We found associations between wider M2–M2 bifurcation angles or narrower A1–A2 bifurcation angles and IA presence, consistent with prior literature. Moreover, we uncovered previously unexplored associations, including wider Pcom–C7 bifurcation angles and smaller internal carotid artery diameters in individuals with Pcom IAs. Future research should explore the potential of these markers in predicting IAs in at‐risk populations during follow‐up screenings.

Endovascular Therapy and Outcomes Among Patients With Very Large Ischemic Core Stroke

The association of endovascular therapy (EVT) with outcomes is unclear for patients with very low Alberta Stroke Program Early Computed Tomography Score (ASPECTS) within 24 hours of stroke onset. To explore the association of EVT with functional and safety outcomes among patients with ASPECTS of 0 to 2 scored with noncontrast computed tomography. This cohort study used data from an ongoing, prospective, observational, nationwide registry including all patients treated at 38 stroke centers in China with an occlusion in the internal carotid artery or M1 or M2 segment of the middle cerebral artery within 24 hours of witnessed symptom onset. Patients with ASPECTS of 0 to 2 between November 1, 2021, and February 8, 2023, were included in analysis. Data were analyzed October to November 2023. EVT vs standard medical treatment (SMT). The primary outcome was favorable functional outcome, defined as modified Rankin Scale score (mRS) of 0 to 3, at 90 days. Safety outcomes included symptomatic intracerebral hemorrhage (sICH) within 48 hours and mortality at 90 days. A total of 245 patients (median [IQR] age, 71 [63-78] years; 118 [48%] women) with ASPECTS of 0 to 2 were included, of whom 111 patients (45.1%) received SMT and 135 patients (54.9%) received EVT. The EVT group had significantly greater odds of favorable functional outcome at 90 days than the SMT group (30 patients [22.2%] vs 11 patients [9.9%]; P = .01; adjusted odds ratio [aOR], 3.07 [95% CI, 1.29-7.31]; P = .01). Patients in the EVT group, compared with the SMT group, had significantly greater odds of any ICH (56 patients [41.5%] vs 16 patients [11.4%]; P < .001; aOR, 4.27 [95% CI, 2.19-8.35]; P < .001) and sICH (24 patients [17.8%] vs 1 patient [0.9%]; P < .001; aOR, 23.07 [95% CI, 2.99-177.79]; P = .003) within 48 hours. There were no differences between groups for 90-day mortality (80 patients [59.3%] vs 59 patients [53.2%]; P = .34; aOR, 1.38 [95% CI, 0.77-2.47]; P = .28). The results remained robust in the propensity score-matched analysis. In this cohort study of patients with very low ASPECTS based on NCCT within 24 hours of stroke onset, those treated with EVT had higher odds of a favorable functional outcome compared with those who received SMT. Randomized clinical trials are needed to assess these findings.

Comparison of 4 mm-sized and 3 mm-sized Stent Retrievers in Mechanical Thrombectomy for M2 Occlusion.

A stent retriever (SR) is widely used in mechanical thrombectomy (MT) for M2 segment occlusion. However, the suitable size of SR in M2 occlusion remains unclear. Therefore, we aimed to compare 4 mm-sized SR with 3 mm-sized SR in M2 occlusion. Patients who underwent MT with SR for M2 occlusion were dichotomized into 4×20 mm SR and 3×20 mm SR groups. Then, 1:1 propensity score matching was performed. The M2 segment was divided into proximal and distal segments according to the occlusion site. Subgroup analysis was then performed for each cohort. A total of 111 patients were enrolled, with 4×20 mm SR and 3×20 mm SR applied in 72 (64.9%) and 39 (35.1%) cases, respectively. In propensity score matching, mean number of stent passages for reperfusion was significantly lower in the 4×20 mm SR group than in the 3×20 mm SR group (1.5 ± 0.8 vs. 2.1 ± 1.1; p = 0.004). First-pass reperfusion (FPR) was more highly achieved in the 4×20 mm SR group than in the 3×20 mm SR group (52.6% vs. 42.1%; p = 0.007). In both proximal and distal occlusion cohorts, the 4 mm SR group showed lower mean number of SR passage (p = 0.004 and p = 0.003, respectively) and higher FPR rate than the 3 mm SR group (p = 0.003 and p = 0.007, respectively). In MT for M2 occlusion, 4×20 mm SR enables an effective procedure with lesser SR passage for reperfusion and a higher rate of FPR than 3×20 mm SR.