M1 Segment Research Articles

Incidence and clinical outcomes of perforations during mechanical thrombectomy for medium vessel occlusion in acute ischemic stroke: A retrospective, multicenter, and multinational study.

Mechanical thrombectomy (MT) has revolutionized the treatment of acute ischemic stroke (AIS) due to large vessel occlusion (LVO), but its efficacy and safety in medium vessel occlusion (MeVO) remain less explored. This multicenter, retrospective study aims to investigate the incidence and clinical outcomes of vessel perforations (confirmed by extravasation during an angiographic series) during MT for AIS caused by MeVO. Data were collected from 37 academic centers across North America, Asia, and Europe between September 2017 and July 2021. A total of 1373 AIS patients with MeVO underwent MT. Baseline characteristics, procedural details, and clinical outcomes were analyzed. The incidence of vessel perforation was 4.8% (66/1373). Notably, our analysis indicates variations in perforation rates across different arterial segments: 8.9% in M3 segments, 4.3% in M2 segments, and 8.3% in A2 segments (p = 0.612). Patients with perforation had significantly worse outcomes, with lower rates of favorable angiographic outcomes (TICI 2c-3: 23% vs 58.9%, p < 0.001; TICI 2b-3: 56.5% vs 88.3%, p < 0.001). Functional outcomes were also worse in the perforation group (mRS 0-1 at 3 months: 22.7% vs 36.6%, p = 0.031; mRS 0-2 at 3 months: 28.8% vs 53.9%, p < 0.001). Mortality was higher in the perforation group (30.3% vs 16.8%, p = 0.008). This study reveals that while the occurrence of vessel perforation in MT for AIS due to MeVO is relatively rare, it is associated with poor functional outcomes and higher mortality. The findings highlight the need for increased caution and specialized training in performing MT for MeVO. Further prospective research is required for risk mitigation strategies.

Ayurvedic management of Hemorrhagic Stroke : A Case Report

WHO defines stroke as a "neurological deficit of cerebrovascular cause that persists beyond 24 hours or is interrupted by death within 24 hours". There are two main types of stroke: ischemic, due to lack of blood flow, and hemorrhagic, due to bleeding. Both cause parts of the brain to stop functioning properly. Stroke is a major global public health problem. According to the Global Burden of Diseases (GBD) study in 1990, stroke was the second leading cause of death worldwide. Subsequent efforts to update the GBD study reported nearly 5.87 million stroke deaths globally in 2010.With the rising proportion of mortality, stroke still remains the second leading cause of death worldwide. The present study is a diagnosed case of ruptured right DACA aneurysm and unruptured right MCA M1 segment aneurysm and ICD (International classification of diseases) classification as Subarchnoid hemorrhage from middle cerebral artery. The patient presented with symptoms of loss of strength and weakness in left upper &amp; lower extremity with stiffness. The Ayurvedic diagnosis of Vama Pakshaghata was done and managed with Dhanyamla Seka, Abhyanga, Shastika Shali Pinda Sweda, Dhara and Matrabasti. Two assessments were made before and after treatment using the National Institute of Health Stroke Scale (NIH-SS). The patient got significant improvement in the signs and symptoms and improvement in movements within 45 days. The results were remarkably encouraging.

Surgical treatment of intracranial epithelioid hemangioendothelioma: a case report

Epithelioid hemangioendothelioma (EHE) is an extremely rare vascular neoplasm with an intermediate pattern of malignancy between benign neoplasms and angiosarcomas. Only 46 cases of intracranial localization of primary EHE in adults have been published.Case report: A 47-year-old male patient developed pronounced speech disorder of sensory and amnestic aphasia type, right-sided pyramidal hemiparesis within 3–4 days. Magnetic resonance imaging revealed a delimited left sided brain islet neoplasm with signs of hemorrhage and small perifocal edema. Intraoperatively, the neoplasm was represented by a conglomerate of pathologic vessels, with involvement of the terminal branches of the M2 segment of the middle cerebral artery, which prevented radical resection of the neoplasm. Based on histopathological and immunohistochemistry analysis of the neoplasm (positive expression of CD31, CD34, proliferative activity index Ki-67 10%) the morphologic diagnosis of EHE was established. 3 months after surgery, continued growth of the residual part of the neoplasm was noted. Temozolomide chemotherapy was clinically ineffective. The patient died due to the development of dislocation syndrome after 9 months.Discussion. The malignant characteristics of EHE include invasive growth, recurrence, and metastasis, which is more common in intracranial localization of the neoplasm. If EHE is suspected, radical surgical removal of the neoplasm should be sought.

Assessment of language lateralization in epilepsy patients using the super-selective Wada test

BackgroundThe classical Wada test (cWada), performed by injecting a short-acting anesthetic through the intracarotid route, helps determine language dominance. In the cWada, adverse effects are observed in 10–30% of trials, hindering accurate assessments. In this study, we assessed the effectiveness of the super-selective Wada test (ssWada), a more selective approach for anesthetic infusion into the middle cerebral artery (MCA).MethodsWe retrospectively examined the data of 17 patients with epilepsy who underwent ssWada via anesthetic injection into one M1 segment of the MCA and at least one contralateral trial.ResultsThe ssWada identified 12 patients with left language dominance, 3 with right language dominance, and 2 with bilateral language distribution. Nine trials on the language dominant side resulted in global aphasia for patients with left- or right language dominance. Of the 13 trials conducted on the non-dominant language side, 12 revealed intact language function and one resulted in confusion. Among these, the outcomes of global aphasia or no language impairment were confirmed in the contralateral trials. Among the 22 trials of unilateral M1 injections in patients with unilateral language dominance, 21 (95.5%) showed either global aphasia or no language impairment, indicating language dominance.ConclusionsThe ssWada yields clear results, with a high rate of over 90% in determining the language dominant hemisphere with few side effects.

Endovascular Thrombectomy Treatment Effect in Direct vs Transferred Patients With Large Ischemic Strokes

Patients with large ischemic core stroke have poor clinical outcomes and are frequently not considered for interfacility transfer for endovascular thrombectomy (EVT). To assess EVT treatment effects in transferred vs directly presenting patients and to evaluate the association between transfer times and neuroimaging changes with EVT clinical outcomes. This prespecified secondary analysis of the SELECT2 trial, which evaluated EVT vs medical management (MM) in patients with large ischemic stroke, evaluated adults aged 18 to 85 years with acute ischemic stroke due to occlusion of the internal carotid or middle cerebral artery (M1 segment) as well as an Alberta Stroke Program Early CT Score (ASPECTS) of 3 to 5, core of 50 mL or greater on imaging, or both. Patients were enrolled between October 2019 and September 2022 from 31 EVT-capable centers in the US, Canada, Europe, Australia, and New Zealand. Data were analyzed from August 2023 to January 2024. EVT vs MM. Functional outcome, defined as modified Rankin Scale (mRS) score at 90 days with blinded adjudication. A total of 958 patients were screened and 606 patients were excluded. Of 352 enrolled patients, 145 (41.2%) were female, and the median (IQR) age was 66.5 (58-75) years. A total of 211 patients (59.9%) were transfers, while 141 (40.1%) presented directly. The median (IQR) transfer time was 178 (136-230) minutes. The median (IQR) ASPECTS decreased from the referring hospital (5 [4-7]) to an EVT-capable center (4 [3-5]). Thrombectomy treatment effect was observed in both directly presenting patients (adjusted generalized odds ratio [OR], 2.01; 95% CI, 1.42-2.86) and transferred patients (adjusted generalized OR, 1.50; 95% CI, 1.11-2.03) without heterogeneity (P for interaction = .14). Treatment effect point estimates favored EVT among 82 transferred patients with a referral hospital ASPECTS of 5 or less (44 received EVT; adjusted generalized OR, 1.52; 95% CI, 0.89-2.58). ASPECTS loss was associated with numerically worse EVT outcomes (adjusted generalized OR per 1-ASPECTS point loss, 0.89; 95% CI, 0.77-1.02). EVT treatment effect estimates were lower in patients with transfer times of 3 hours or more (adjusted generalized OR, 1.15; 95% CI, 0.73-1.80). Both directly presenting and transferred patients with large ischemic stroke in the SELECT2 trial benefited from EVT, including those with low ASPECTS at referring hospitals. However, the association of EVT with better functional outcomes was numerically better in patients presenting directly to EVT-capable centers. Prolonged transfer times and evolution of ischemic change were associated with worse EVT outcomes. These findings emphasize the need for rapid identification of patients suitable for transfer and expedited transport. ClinicalTrials.gov Identifier: NCT03876457.

Endovascular Thrombectomy for Large Ischemic Stroke Across Ischemic Injury and Penumbra Profiles

Whether endovascular thrombectomy (EVT) efficacy for patients with acute ischemic stroke and large cores varies depending on the extent of ischemic injury is uncertain. To describe the relationship between imaging estimates of irreversibly injured brain (core) and at-risk regions (mismatch) and clinical outcomes and EVT treatment effect. An exploratory analysis of the SELECT2 trial, which randomized 352 adults (18-85 years) with acute ischemic stroke due to occlusion of the internal carotid or middle cerebral artery (M1 segment) and large ischemic core to EVT vs medical management (MM), across 31 global centers between October 2019 and September 2022. EVT vs MM. Primary outcome was functional outcome-90-day mRS score (0, no symptoms, to 6, death) assessed by adjusted generalized OR (aGenOR; values >1 represent more favorable outcomes). Benefit of EVT vs MM was assessed across levels of ischemic injury defined by noncontrast CT using ASPECTS score and by the volume of brain with severely reduced blood flow on CT perfusion or restricted diffusion on MRI. Among 352 patients randomized, 336 were analyzed (median age, 67 years; 139 [41.4%] female); of these, 168 (50%) were randomized to EVT, and 2 additional crossover MM patients received EVT. In an ordinal analysis of mRS at 90 days, EVT improved functional outcomes compared with MM within ASPECTS categories of 3 (aGenOR, 1.71 [95% CI, 1.04-2.81]), 4 (aGenOR, 2.01 [95% CI, 1.19-3.40]), and 5 (aGenOR, 1.85 [95% CI, 1.22-2.79]). Across strata for CT perfusion/MRI ischemic core volumes, aGenOR for EVT vs MM was 1.63 (95% CI, 1.23-2.16) for volumes ≥70 mL, 1.41 (95% CI, 0.99-2.02) for ≥100 mL, and 1.47 (95% CI, 0.84-2.56) for ≥150 mL. In the EVT group, outcomes worsened as ASPECTS decreased (aGenOR, 0.91 [95% CI, 0.82-1.00] per 1-point decrease) and as CT perfusion/MRI ischemic core volume increased (aGenOR, 0.92 [95% CI, 0.89-0.95] per 10-mL increase). No heterogeneity of EVT treatment effect was observed with or without mismatch, although few patients without mismatch were enrolled. In this exploratory analysis of a randomized clinical trial of patients with extensive ischemic stroke, EVT improved clinical outcomes across a wide spectrum of infarct volumes, although enrollment of patients with minimal penumbra volume was low. In EVT-treated patients, clinical outcomes worsened as presenting ischemic injury estimates increased. ClinicalTrials.gov Identifier: NCT03876457.

Neurological Improvement by One-Thirds Is Associated With Early Recanalization in Stroke With Large Vessel Occlusion.

A proportion of large vessel occlusion strokes demonstrate early recanalization, obviating the initial intention to proceed to endovascular thrombectomy. Neurological improvement is a possible surrogate marker for reperfusion. We aimed to determine the optimal threshold of neurological improvement, as defined by the National Institutes of Health Stroke Scale (NIHSS), which best associates with early recanalization. We retrospectively analyzed consecutive patients with large vessel occlusion transferred from primary stroke centers to a tertiary comprehensive stroke center in Melbourne, Australia, for possible endovascular thrombectomy from January 2018 to December 2022. Absolute and percentage changes in NIHSS between transfer, as well as other definitions of neurological improvement, were compared using receiver operating characteristic curve analysis for association with recanalization as defined by the absence of occlusion in the internal carotid artery, middle cerebral artery (M1 or M2 segments), or basilar artery on repeat vascular imaging. Six hundred and fifty-four transferred patients with large vessel occlusion were included in the analysis: mean age was 68.8±14.0 years, 301 (46.0%) were women, and 338 (52%) received intravenous thrombolytics. The proportion of extracranial internal carotid artery, intracranial internal carotid artery, M1, proximal M2, and basilar artery occlusion was 18.8%, 13.6%, 48.3%, 15.0%, and 4.3%, respectively, on initial computed tomography angiogram. Median NIHSSprimary stroke center and NIHSScomprehensive stroke center scores were 15 (interquartile range, 9-18) and 13 (interquartile range, 8-19), respectively. Early recanalization occurred in 82 (13%) patients. NIHSS reduction of ≥33% was the best tradeoff between sensitivity (64%) and specificity (83%) for identifying recanalization. NIHSS reduction of ≥33% had the highest discriminative ability to predict recanalization (area under the curve, 0.735) in comparison with other definitions of neurological improvement. One-third neurological improvement between the primary hospital and tertiary center was the best predictor of early recanalization.

Variation in Vessel Size and Angiographic Outcomes Following Stent‐Retriever Thrombectomy in Acute Ischemic Stroke: STRATIS Registry

Background Mechanical thrombectomy is established for large‐vessel occlusions in acute ischemic stroke, but the potential role in distal vessel occlusions of medium arteries is less well established. Such medium or distal arterial segments have not been assessed with respect to thrombectomy devices used during endovascular therapy. We conducted an analysis of arterial size, segmental anatomy, and stent‐retriever device performance with respect to vessel size during thrombectomy. Methods The STRATIS registry angiography core laboratory adjudicated the exact location of the occlusion, proximal, and distal device deployment, relationship to arterial bifurcations, and anatomic nomenclature. Arterial diameters were measured at all these sites. Statistical analyses examined the relationship between vessel and stent size, and arterial recanalization using expanded Thrombolysis in Cerebral Infarction reperfusion score. Results Overall, 665 patients with stroke were included following thrombectomy using various Solitaire device sizes, including Solitaire 4×40, Solitaire 6×30, Solitaire 4×20, Solitaire 6×20, and Solitaire 4×15. Arterial diameter at the occlusion site was a median of 2.17 mm (interquartile range [IQR], 1.88–2.60 mm) in the distal M1, 1.67 mm (IQR, 1.47–2.06 mm) in the proximal M2 middle cerebral artery, 1.50 mm (IQR, 1.15–1.61 mm) in the distal M2 middle cerebral artery, 1.24 mm (IQR, 1.11–1.24 mm) in the M3 middle cerebral artery, and 1.88 mm (IQR, 1.49–1.94 mm) in the P1 posterior cerebral artery. Expanded Thrombolysis in Cerebral Infarction 2b to 3 reperfusion was achieved in all M3 or P1 segment occlusions. The rate of first‐pass recanalization was significantly higher in patients with medium (0.75–2 mm) versus large (&gt;2 mm) vessel occlusion (69.5% versus 57.1%; P = 0.003). Conclusion Considerable overlap was noted between arterial sizes at occlusion sites carrying different segmental arterial nomenclature or vessel names. Substantial reperfusion may be achieved with currently available mechanical thrombectomy devices in medium arteries.

Risk factor analysis of changes in blood flow in the A1 segment of the anterior cerebral artery after flow-diverter coverage of it.

Few studies have explored the effect of a flow-diverter device (FD) on blood flow in the A1 segment of the anterior cerebral artery (ACA), after treatment of intracranial aneurysms in the bifurcation region of the internal carotid artery (ICA). The main objective of this article is to investigate the factors that affect A1 blood flow after FD covers the A1 artery. This is a single-center, retrospective study. Data were collected retrospectively from our center, and patients whose FDs were placed for treatment from the terminal of the ICA to the M1 segment were analyzed. A total of 42 patients were included in the study. Immediate post-procedural angiography following device placement revealed decreased blood flow in the A1 of 15 (35.7%) patients and complete occlusion of the A1 segment in 11 (26.2%) patients. During an average follow-up period of 9.8months, the A1 segment was ultimately occluded in 25 patients (59.5%) and decreased blood flow in 4 patients (9.5%). When using FD to cover the A1 artery for the treatment of intracranial aneurysms, patients with preoperative opening of the anterior communicating artery (AcomA) are more prone to occlusion or decreased blood flow of the A1 artery, compared to patients without opening.

Abstract TP201: Impact of Microguide Wire Stiffness on Microcatheter and Aspiration Catheter Navigation in Tortuous Vessels

Background and Purpose: Endovascular therapies require devices to access treatment sites safely and efficiently. Vessel tortuosity often complicates this navigation, increasing the risk of microguide wire (MGW) or microcatheter (MC) kickback, which may result in unstable device movements or sudden drop of devices. This study aims to elucidate the effect of MGW stiffness variability on the trackability of MC and aspiration catheters (AC). Methods: Using two silicone vascular models, we replicated the M2 segment of the middle cerebral artery (MCA) at an 80-degree branch (MCA model, Fig. A) and a severely tortuous internal carotid artery (ICA model, Fig. B). Experiments were conducted under conditions of 37°C, 60 BPM, and an ICA flow rate of 240 mL/min. In the MCA model, the MC (TrevoTrak21) was advanced from the M1 segment to distal M2 while three MGWs (Synchro SELECT Soft, Standard, Support) were placed at distal M2. In the ICA model, the AC (Zoom 71) was advanced from ICA to M1 with MC and MGW at distal M2. Maximum push force and kickback length were measured while TrevoTrack21 or Zoom71 were advanced at 4 mm/sec for 7 runs per device. One-way ANOVA assessed group differences. Results: In the MCA model, when using the Soft MGW, the MC recorded the highest pushing force at 59.3mN and kickback of 29.87mm. Conversely, the Support MGW demonstrated the least pushing force at 38.2mN (P&lt;0.001) and the shortest kickback length at 17.83mm (P&lt;0.001). For the ICA model, differences in forces across the MGW types were less distinct. However, the kickback length with the Soft MGW at 13.78mm was significantly greater than that with the Standard MGW at 6.26mm and the Support MGW at 6.76mm (P=0.026). Conclusion: Our findings suggest that MGWs with higher stiffness offer more stable guidance, requiring less force in both MC and AC navigation. Moreover, increased MGW stiffness consistently leads to shorter kickback lengths, emphasizing its importance in stable device navigation.

Abstract TP219: Outcomes and Differences by Occluded Vessel in the Endovascular Treatment for Acute Ischemic Stroke Patients With Medium Vessel Occlusion

Introduction: The outcomes of mechanical thrombectomy (MT) for patients with acute ischemic stroke (AIS) caused by medium vessel occlusions (MeVOs) in different vessels remains unknown. The aim of this study is to investigate MT outcomes in AIS patients with isolated MeVOs in different occluded vessel segments using the data from an ongoing international multicenter registry, the Stroke Thrombectomy and Aneurysm Registry (STAR). The aim of this study is to investigate MT outcomes in AIS patients with isolated MeVOs in different occluded vessel segments using the data from an ongoing international multicenter registry, the Stroke Thrombectomy and Aneurysm Registry (STAR). Methods: 110 AIS patients with MeVO who undertook MT between January 2010 and December 2022 were retrospectively investigated. MeVO was defined as isolated occlusion of the A2 or A3 (A23O) segment of the anterior cerebral artery, M3 segment of the middle cerebral artery (M3O), and P2 or P3 segment of the posterior cerebral artery (P23O). The primary outcome measure was a 90-day modified Rankin score (mRS) 0-2. The 90-day mRS 0-1, any intracranial hemorrhage, symptomatic intracranial hemorrhage, and 90-day mortality were used as secondary outcomes. Outcomes were compared between A23O, M3O, and P23O. Results: Median (interquartile range) age was 68.3 (58.4-76.0) years and 49 patients were female (46.7%). MeVO included 17 A23O (15.5%), 60 M3O (54.5%), and 33 P23O (30.0%).Compared to patients with A23O (17.7%), those with M3O (56.7%) and P23O (45.5%) had a higher proportion of 90-day mRS 0-2 (M3O, adjusted odds ratio 10.3, 95% confidence interval 1.71-62.2, p = 0.01; P23O adjusted odds ratio 8.86, 95% confidence interval 1.32-59.3, p =0.02). Other outcomes showed no significant differences. Conclusions: This study indicates A2O might be related to poorer outcomes compared to M3O and P23 in MT treatment for AIS patients due to isolated MeVO. Efforts should be aimed at improving outcomes following A23O to match those at other MeVO locations.

Abstract WP132: The Significance of Fluid-Attenuated Inversion Recovery Vascular Hyperintensity in Combination With Occlusion Site and Reperfusion Status by Mechanical Thrombectomy for Proximal and Distal Middle Cerebral Artery Occlusion

Introduction: In patients with acute ischemic stroke, FLAIR vascular hyperintensity (FVH) is a reliable indicator of large vessel occlusion and salvageable tissue requiring mechanical thrombectomy (MT). However, its significance in distal arterial occlusion has not been established. This study aimed to investigate the significance of FVH in DWI-negative areas, in combination with occlusion site and reperfusion status, by MT for regional tissue outcomes in proximal and distal middle cerebral artery (MCA) occlusion. Methods: The clinical records of patients admitted to a single institute between April 2017 and June 2022, who presented with MCA occlusion with initial NIHSS ≥ 5 and underwent MT within 24 h of onset were retrospectively analyzed. Proximal occlusion was defined as M1 segment occlusion, and distal occlusion as M2 or M3 segment based on initial MRA. Each cortical MCA area in Alberta Stroke Program Early CT Score (ASPECTS) ipsilateral to the occluded vessel was categorized into group A (DWI-, FVH-) or B (DWI-, FVH+) based on initial MRI. Regional collateral status on initial angiogram, expanded Thrombolysis in Cerebral Infarction (eTICI) grade on final angiogram, and regional unfavorable tissue outcome with the appearance of low or high density on CT 24 h after MT were recorded. Univariate and multivariate analyses using mixed-effects models for regional unfavorable tissue outcome were performed. Results: A total of 103 patients (56 with proximal and 47 with distal occlusion) were included. Categorizing cortical areas resulted in 256 areas in group A and 171 in group B. The rate of unfavorable tissue outcome in order of eTICI 0-2a, 2b50-67, and 2c-3 reperfusion status in group A were 14.3%, 11.3%, and 6.0%, respectively (p=0.06) while those in group B were 47.1%, 34.0%, and 12.9%, respectively (p&lt;0.01). In multivariate analysis, eTICI 0-2b67 vs. eTICI 2c-3 in group B of distal occlusion was an independent predictor for unfavorable regional tissue outcome (OR 7.8, 95% CI 1.1-55.6, p=0.04), along with ASPECTS M2 or M5 and poor angiographical collaterals. Conclusions: FVH in DWI-negative areas can reveal penumbra tissue secondary to both proximal and distal MCA occlusions. However, salvage requires fairly reliable reperfusion in distal occlusion.

A foreign body that has been left for 20 years causes a pseudoaneurysm of the middle cerebral artery: a case report

BackgroundWe report a patient with extensive subarachnoid hemorrhage caused by the rupture of a middle cerebral artery pseudoaneurysm from a foreign body that had been left for two decades.Case presentationA 74-year-old male patient from Han nationality was admitted to the emergency department of our hospital with impaired consciousness for 1 hour. Cranial computed tomography examination indicated a massive subarachnoid hemorrhage with intraventricular blood accumulation, and a high-density short strip dense shadow was seen in the M1 segment of the right middle cerebral artery, considering the possibility of a foreign body. Subsequently, a cerebral angiography was suggested; the foreign body was seen through the right middle cerebral artery, and the aneurysm was seen in the lower wall, so a pseudoaneurysm was considered. The emergent surgical intervention involved the clipping of the pseudoaneurysm and intracranial extraction of the foreign body. Unfortunately,the patient ultimately expired due to severe pulmonary infection.ConclusionIntracranial pseudoaneurysm caused by foreign body has been rarely reported previously, and microsurgical treatment of an intracranial pseudoaneurysm caused by a foreign body is a good choice.

Contrast-induced encephalopathy after an embolization procedure for a cerebral aneurysm in a female with subarachnoid hemorrhage: a case report

BackgroundContrast-induced encephalopathy (CIE) is a rare complication during or after angiography, usually transient and reversible. CIE diagnosis is challenging due to the absence of no formal diagnostic criteria. CIE can mimic stroke symptoms, including visual disturbances, seizures, confusion, coma, and focal neurological deficits. This case reports neurological deficit reversal in a CIE patient due to the embolization of an intracranial aneurysm, the second angiographic procedure in six days.Case presentationA 77-year-old woman was admitted to the hospital for headaches. The cerebral computed tomography (CT) scan indicated a subarachnoid hemorrhage. The first digital subtraction angiography (DSA) identified an aneurysm of 4 mm ∗ 3 mm in size in the M1 segment of the right middle cerebral artery (MCA). Then, embolization surgery was performed for the cerebral aneurysm, which was successful. However, the patient had post-operative headaches, slurred speech, epilepsy, limb weakness, and delirium post-procedure. The non-contrast cerebral CT indicated widespread edema in the right cerebral hemisphere. The patient was diagnosed with CIE and treated with symptomatic supportive therapy. Eventually, the patient’s neurological deficits and cerebral edema improved significantly.ConclusionsThe current case emphasized the importance of early diagnosis and symptomatic treatment of CIE. Thus, CIE should be the first consideration during the differential diagnosis of a patient having acute neurological impairment after repeated DSA.

A "Radial Ready" Tricoaxial Setup for Anterior Circulation Mechanical Thrombectomy: Technical Aspects and Preliminary Results.

Mechanical thrombectomy (MT) is the standard of care for acute ischemic stroke (AIS) due to large vessel occlusion (LVO). The choice of a transradial approach (TRA) for anterior circulation LVOs is still debatable; the use of a specific tricoaxial system could help mitigate numerous issues related to transradial MT. From November 2022 to November 2023, 22 patients underwent TRA-MT for anterior circulation LVOs, both as first-line and rescue from transfemoral approach (TFA) failure, with the same triaxial setup consisting of a 7F introducer sheath, 7F guide catheter, and aspiration catheters ranging from 5.5F to 5F in relation to the occlusion site. Choice of thrombectomy technique was at operator discretion. Patients' demographic data, clinical presentation, treatment details, complications, rate of crossover to TFA, successful revascularization (modified thrombolysis in cerebral infarction [mTICI] score ≥2b), and good clinical outcome at 3 months (modified Rankin scale [mRS] 0-2) were reported. Of 20 patients selected, 10 (50%) had occlusion of M1 segment of middle cerebral artery (MCA), 6 (30%) of internal carotid artery (ICA) terminus, and 4 (20%) with M2 MCA occlusions; 12/20 (60%) were right-sided occlusions and 8/20 (40%) were left-sided. The mean National Institutes of Health Stroke Scale score was 9.25 at admission. Successful revascularization to mTICI 2b-3 was achieved in 18/20 patients (90%). Intracranial complications were reported in 2 (10%) patients. Rate of radial artery occlusion at 24 hours was 10,6%; no access-site haemorrhagic complications were reported. Symptomatic intracranial hemorrhage occurred in 2 (10%) patients. mRS score 0-2 at 3 months was 50%. The high technical effectiveness and good safety profile of this specific tricoaxial setup for TRA-MT in AIS, even for large proximal LVOs, could constitute a viable alternative to TFA-MT in selected cases.

Twig-like middle cerebral artery as a variety of isolated middle cerebral artery disease with new vessel formation: illustrative case.

Twig-like middle cerebral artery (T-MCA) is reported as a rare vascular anomaly characterized by reconstitution of the M1 segment of the middle cerebral artery (MCA) by a plexiform network of small vessels. Although it is generally believed that the etiology of T-MCA is an embryological persistence, some investigators have suggested that T-MCA may be a secondary consequence. Here, the authors report a second case of de novo T-MCA formation and reconsider the concept of T-MCA in connection with isolated MCA disease. A 40-year-old man's brain magnetic resonance imaging (MRI) checkup showed moderate stenosis of the M1 segment of the left MCA. Annual MRI follow-up was planned, and when performed 1 year later, it showed occlusion of the M1 segment of the left MCA. Cerebral angiography revealed occlusion of that M1 segment with abnormal arterial networks. This case was diagnosed as de novo T-MCA. The patient has remained asymptomatic for 2 years. The reports of de novo T-MCA indicate that acquired factors may be involved in the pathogenesis of T-MCA. We suggest that T-MCA should be defined as a variety of isolated MCA disease with new vessel formation.

Continuous direct intraarterial treatment of meningitis-induced vasospasm in a pediatric patient: illustrative case.

Bacterial meningitis-induced ischemic stroke continues to cause significant long-term complications in pediatric patients. The authors present a case of severe right internal carotid artery terminus and M1 segment vasospasm in a 9-year-old with an infected cholesteatoma, which was refractory to multiple intraarterial treatments with verapamil and milrinone. This is the first report of continuous intraarterial antispasmodic treatment in a pediatric patient as well as the first report of continuous treatment in an awake and extubated patient. Arterial narrowing was successfully treated by continuous direct intraarterial administration of both a calcium channel blocker (verapamil) and a phosphodiesterase-3 inhibitor (milrinone). The patient recovered remarkably well and was discharged home with no neurological deficit (National Institutes of Health Stroke Scale score 0) and ambulatory without assistance after 22 days. The authors report a promising outcome of this technique performed in a pediatric patient. This represents a novel treatment option for the prevention of stroke in pediatric bacterial meningitis. Continuous, direct intraarterial administration of antispasmodic medications can successfully prevent long-term neurological deficit in pediatric meningitis-associated vasospasm. The described method has the potential to significantly improve outcomes in severe pediatric meningitis-associated vasospasm.

Effect of Intravenous Thrombolysis Prior to Mechanical Thrombectomy According to the Location of M1 Occlusion.

The additive effects of intravenous thrombolysis (IVT) before mechanical thrombectomy (MT) remain unclear. We aimed to investigate the efficacy and safety of IVT prior to MT depending on the location of M1 occlusion. We reviewed the cases of patients who underwent MT for emergent large-vessel occlusion of the M1 segment. Baseline characteristics as well as clinical and periprocedural variables were compared according to the location of M1 occlusion (i.e., proximal and distal M1 occlusion). The main outcome was the achievement of functional independence (modified Rankin Scale score, 0-2) at 3 months after stroke. The main outcomes were compared between the proximal and distal groups based on the use of IVT before MT. Among 271 patients (proximal occlusion, 44.6%; distal occlusion, 55.4%), 33.9% (41/121) with proximal occlusion and 24.7% (37/150) with distal occlusion underwent IVT prior to MT. Largeartery atherosclerosis was more common in patients with proximal M1 occlusion; cardioembolism was more common in those with distal M1 occlusion. In patients with proximal M1 occlusion, there was no association between IVT before MT and functional independence. In contrast, there was a significant association between the use of IVT prior to MT (odds ratio=5.30, 95% confidence interval=1.56-18.05, P=0.007) and functional independence in patients with distal M1 occlusion. IVT before MT was associated with improved functional outcomes in patients with M1 occlusion, especially in those with distal M1 occlusion but not in those with proximal M1 occlusion.

The effect of asymptomatic intracranial hemorrhage after mechanical thrombectomy on clinical outcome

Background and objectiveWhether asymptomatic intracranial hemorrhage (ICH) affects the clinical outcomes in patients with acute large vessel occlusion treated with mechanical thrombectomy (MT) remains unclear. This study aimed to address this uncertainty. MethodsWe retrospectively analyzed patients with acute ischemic stroke and internal carotid or middle cerebral (M1 segment) artery occlusion treated with MT between April 2011 and March 2021 at a single center. All patients had a premorbid modified Rankin scale (mRS) score ≤ 2 and an anterior circulation occlusion and underwent magnetic resonance imaging at admission. Asymptomatic ICH was defined as ICH without symptomatic ICH defined by the SITS-MOST criteria. A favorable outcome was defined as an mRS score ≤ 2 at 90 days after stroke onset. ResultsOur study included 349 patients; 62% were men, the median age was 76 [67–83] years, and the median National Institutes of Health Stroke Scale (NIHSS) score was 15 [8–21]. As determined via computed tomography, 103 (30%) patients had ICH (20 symptomatic and 83 asymptomatic). The favorable outcome rate was significantly lower for asymptomatic vs. no ICH (30% vs. 67%, p < 0.01). In a multivariate regression analysis, a high NIHSS score (odds ratio [OR], 1.06; 95% confidence interval [CI], 1.02–1.10; p < 0.01) and low Alberta Stroke Program Early CT Score (OR, 0.78; 95% CI, 0.65–0.92; p < 0.01) were independent risk factors for ICH. ConclusionsAsymptomatic ICH is associated with poor clinical outcome at 90 days after stroke onset.

Effect of computed tomography vs. computed tomography perfusion on mechanical thrombectomy outcomes within 6hours.

It is unclear which selection strategy, plain CT vs. CT perfusion (CTP), is more powerful in predicting outcome after mechanical thrombectomy (MT). We aimed to compare the effect of plain CT and CTP in predicting outcome after MT within 6h. We conducted a prospective analysis of a retrospective cohort from our single-center study, which had occlusion of the internal carotid artery and middle cerebral artery up to the proximal M2 segment and received MT within 6h. According to the Alberta Stroke Program Early CT Score (ASPECTS), patients were divided into a high-ASPECTS group (≥ 6) and a low ASPECTS group (< 6). Similarly, patients were divided into mismatch and no-mismatch groups according to the DEFUSE3 criteria for CTP. A good outcome was defined as a 90-day modified Rankin Scale (mRS) score of ≤ 3. Univariate and binary logistic regression analyses were used to investigate the association between different imaging modality and 90-day mRS score, and mortalities, respectively. The high ASPECTS group included 307 patients (89.2%). The mismatch group included 189 (54.9%) patients meeting the DEFUSE3 criterion. Compared to the low ASPECTS group, the high ASPECTS group had a good outcome (odds ratio (OR), 2.285; [95% confidence interval (CI) (1.106, 4.723)], p = 0.026) and lower mortality (OR, 0.350; [95% CI (0.163, 0.752)], p = 0.007). However, there were no significant differences in good outcomes and mortality between the mismatch and no-mismatch groups. Compared with plain CT, CTP does not provide additional benefits in the selection of patients suitable for MT within 6h. CT perfusion is not superior to plain CT for the prediction of clinical outcomes when selecting patients for mechanical thrombectomy in the first 6h. In that clinical setting, plain CT may be safe in the absence of perfusion data. •The advantage of CT perfusion (CTP) over CT in pre-mechanical thrombectomy (MT) screening has not been proven for patients witha large infarct core. •CTP is not better than plain CT in predicting good outcome following MT within 6h. •Plain CT is sufficient for selecting patients suitable for MT within 6h of large artery occlusion.