Intracranial Vessels Research Articles

The Surgical Management of Intraoperative Intracranial Artery Injury in open Skull Base Surgery - A Series of Three Cases

Background: intracranial surgery is very commonly performed around the world. During these surgeries, intraoperative injury to the major intracranial vessels is a very serious condition. It has to be addressed promptly by either direct repair or vascular bypass. We describe three cases where there was vascular injury during surgery which were managed by direct repair. This implies the necessity of learning microvascular techniques for safely perform the surgery and save the patient from neurological deficits. Bang. J Neurosurgery 2023; 12(2): 122-124

Variability in Intracranial Vessel Diameters and Considerations for Neurovascular Models: A Systematic Review and Meta‐Analysis

Background In vitro experiments are critical for understanding the impact of medical devices and techniques on blood vessels and blood flow. However, their interpretation is often limited by anatomical models’ inability to capture the wide range of vessel sizes observed in real‐world practice. The current study aims to address this limitation by describing the distribution of vessel diameters in a real‐world population. Methods This systematic literature review using the PubMed database analyzed cerebral vessel diameters in patients from 2000 to 2022. The diameter measurements of various vessels within the neurovasculature were extracted. Random‐effects meta‐analyses were performed to synthesize vessel diameters across studies. Predicted distributions were generated from the meta‐analytical results. Results Seventy‐six studies were included in the analysis. The M1 segment, internal carotid artery (cervical and communicating segments), A1 segment, V2 segment, V4 segment, and basilar artery had sufficient data for generating predicted distributions of vessel diameters. Predicted mean diameters were as follows: M1 segment, 2.55 ± 0.42 mm (95th interpercentile range [IPR]: 1.71–3.38); internal carotid artery‐cervical segment, 4.74 ± 0.64 mm (95th IPR: 3.49–5.99); internal carotid artery‐communicating segment, 3.40 ± 0.64 mm (95th IPR: 2.15–4.66); A1 segment, 1.89 ± 0.34 mm (95th IPR: 1.23–2.55); V2 segment, 3.36 ± 0.67 mm (95th IPR: 2.05–4.67); V4 segment, 2.42 ± 0.74 mm (95th IPR: 0.98–3.86); and basilar artery, 2.96 ± 0.52 mm (95th IPR: 1.94–3.97). Conclusion Cerebral vessel diameter measurements can vary substantially due to patient‐specific factors and imaging techniques. This literature review highlights the diverse range of vessel sizes observed in different patient populations, emphasizing the need for anatomical models that accurately represent clinical observations.

Streamlining neuroradiology workflow with AI for improved cerebrovascular structure monitoring

Radiological imaging to examine intracranial blood vessels is critical for preoperative planning and postoperative follow-up. Automated segmentation of cerebrovascular anatomy from Time-Of-Flight Magnetic Resonance Angiography (TOF-MRA) can provide radiologists with a more detailed and precise view of these vessels. This paper introduces a domain generalized artificial intelligence (AI) solution for volumetric monitoring of cerebrovascular structures from multi-center MRAs. Our approach utilizes a multi-task deep convolutional neural network (CNN) with a topology-aware loss function to learn voxel-wise segmentation of the cerebrovascular tree. We use Decorrelation Loss to achieve domain regularization for the encoder network and auxiliary tasks to provide additional regularization and enable the encoder to learn higher-level intermediate representations for improved performance. We compare our method to six state-of-the-art 3D vessel segmentation methods using retrospective TOF-MRA datasets from multiple private and public data sources scanned at six hospitals, with and without vascular pathologies. The proposed model achieved the best scores in all the qualitative performance measures. Furthermore, we have developed an AI-assisted Graphical User Interface (GUI) based on our research to assist radiologists in their daily work and establish a more efficient work process that saves time.

Combined intravenous and intra-arterial thrombolysis in hyperacute cerebral ischemia without significant corresponding vascular occlusion/stenosis: A Preliminary investigation

ObjectiveIn this study, we assessed the efficacy and safety of various thrombolytic treatment protocols in patients with hyperacute cerebral infarction. MethodsPatients diagnosed with acute ischemic stroke within 6 h of symptom onset and with brain computer tomography angiography confirming the absence of major vessel stenosis or occlusion were eligible for this study. The enrolled patients were subsequently randomized into two groups: all the groups received the standard intravenous thrombolysis treatment with rt-PA (0.9 mg/kg), and the experimental group underwent sequential intra-arterial thrombolysis treatment with alteplase (0.3 mg/kg, with a maximum dose of 22 mg), administered directly into the target vessel via a microcatheter. Both groups were closely monitored for changes in their National Institutes of Health Stroke Scale (NIHSS) score, modified Rankin scale score, hemorrhage rate, all-cause mortality rate, and the rate of favorable outcomes at 90 ± 7 days. ResultsNinety-four participants were enrolled in this study, with both the control and experimental groups initiating intravenous injection of rt-PA at a median time of 29 min. For the experimental group, the median time for arterial puncture was 123 min. Baseline data for both groups were similar (P > 0.05). Hemorrhagic transformation occurred in 24.47 % (23 patients), with a lower intracranial hemorrhage rate observed in the experimental group compared to the control group (15.2 % vs 33.3 %, P < 0.05). Asymptomatic hemorrhage rates were 8.7 % for the experimental group and 12.5 % for the control group, with no hemorrhage detected in other locations. Post-treatment median NIHSS scores were lower in the experimental group than in the control group (7 vs 9, P < 0.05), but short-term NIHSS scores were similar (P > 0.05). A higher proportion of patients in the experimental group achieved favorable outcomes compared to the control group (87.0 % vs 43.8 %, P < 0.05). ConclusionIn patients with acute ischemic stroke with an onset time of ≤6 h and no major intracranial vessel occlusion, combining rt-PA intravenous thrombolysis with intra-arterial thrombolysis via a microcatheter might yield superior functional outcomes.

Optimization-derived blood input function using a kernel method and its evaluation with total-body PET for brain parametric imaging

Dynamic PET allows quantification of physiological parameters through tracer kinetic modeling. For dynamic imaging of brain or head and neck cancer on conventional PET scanners with a short axial field of view, the image-derived input function (ID-IF) from intracranial blood vessels such as the carotid artery (CA) suffers from severe partial volume effects. Alternatively, optimization-derived input function (OD-IF) by the simultaneous estimation (SIME) method does not rely on an ID-IF but derives the input function directly from the data. However, the optimization problem is often highly ill-posed. We proposed a new method that combines the ideas of OD-IF and ID-IF together through a kernel framework. While evaluation of such a method is challenging in human subjects, we used the uEXPLORER total-body PET system that covers major blood pools to provide a reference for validation. MethodsThe conventional SIME approach estimates an input function using a joint estimation together with kinetic parameters by fitting time activity curves from multiple regions of interests (ROIs). The input function is commonly parameterized with a highly nonlinear model which is difficult to estimate. The proposed kernel SIME method exploits the CA ID-IF as a priori information via a kernel representation to stabilize the SIME approach. The unknown parameters are linear and thus easier to estimate. The proposed method was evaluated using 18F-fluorodeoxyglucose studies with both computer simulations and 20 human-subject scans acquired on the uEXPLORER scanner. The effect of the number of ROIs on kernel SIME was also explored. ResultsThe estimated OD-IF by kernel SIME showed a good match with the reference input function and provided more accurate estimation of kinetic parameters for both simulation and human-subject data. The kernel SIME led to the highest correlation coefficient (R = 0.97) and the lowest mean absolute error (MAE = 10.5 %) compared to using the CA ID-IF (R = 0.86, MAE = 108.2 %) and conventional SIME (R = 0.57, MAE = 78.7 %) in the human-subject evaluation. Adding more ROIs improved the overall performance of the kernel SIME method. ConclusionThe proposed kernel SIME method shows promise to provide an accurate estimation of the blood input function and kinetic parameters for brain PET parametric imaging.

Vessel wall imaging in the diagnosis of antiphospholipid syndrome presenting as Moyamoya syndrome-A case report.

Objectives: We describe a case of anti-phospholipid syndrome (APLS) vasculopathy presenting with Moyamoya syndrome (MMS) and show the associated intracranial vessel wall MRI (VWI) findings. Methods: A 37-year-old-woman presented with acute onset dizziness and left-sided weakness. Neurologic exam revealed a left facial droop and left hemiparesis. She underwent a comprehensive laboratory work-up for stroke. Neuroimaging included a CT head, CT angiogram, VWI, and digital subtraction angiography. Results: Work-up revealed a triple-positive APLS antibody profile. CT of the head showed an acute right basal ganglia infarction and right frontal subarachnoid hemorrhage. CT angiogram revealed severe stenosis of the right internal carotid artery terminus in a Moyamoya pattern. Intracranial VWI showed long-segment concentric vessel wall thickening and homogeneous vessel wall enhancement and T2-hyperintense wall edema of the stenotic right ICA terminus, M1 middle cerebral artery, and A1 anterior cerebral artery. She was treated with long-term anticoagulation with warfarin and a right superficial temporal artery to middle cerebral artery bypass. Discussion: We present intracranial VWI features of vessel wall pathology in a patient with primary APLS presenting with MMS.

Novel Technique of Stent Placement via Gateway Balloon in Intracranial Atherosclerosis-associated Large Vessel Occlusion (P3-5.019)

Novel Technique of Stent Placement via Gateway Balloon in Intracranial Atherosclerosis-associated Large Vessel Occlusion (P3-5.019)

Progression of Intracranial Artery Stenosis and Cerebral Small Vessel Disease and Associations Between the Two Entities: A Prospective Community-based Cohort Study (S6.003)

Progression of Intracranial Artery Stenosis and Cerebral Small Vessel Disease and Associations Between the Two Entities: A Prospective Community-based Cohort Study (S6.003)

Traditional Thrombus Composition and Related Endovascular Outcomes: Catching up with the Recent Evidence.

Endovascular thrombectomy is the primary treatment for acute intracranial vessel occlusion and significantly improves recanalization success rate. However, achieving optimal recanalization remains a challenge. The histopathological components of thrombus composition play a crucial role in determining endovascular outcomes. This review aimed to consolidate the recent evidence on the impact of thrombus composition on mechanical properties and endovascular outcomes. The relationship between thrombus composition and mechanical properties was significant, with fibrin and/or platelet-rich thrombi being stiff, tough, elastic, and less deformable; fibrin-rich thrombi were sticky and had higher friction with the vessel wall. Erythrocyte composition was positively associated with successful recanalization, whereas lower platelet composition was associated with specific outcomes, such as the first-pass effect and complete recanalization. The number of thrombectomy device passes was possibly related to erythrocyte, platelet, and fibrin composition, with a smaller number of passes associated with erythrocyte-rich thrombi. Procedural time was consistently related to thrombus composition, with shorter times observed for erythrocyte-rich thrombi. The relationship between thrombus composition and secondary embolism remains inconclusive. Understanding the role of thrombus composition in endovascular outcomes is crucial to optimize stroke treatment. Although evidence suggests a link between thrombus composition and mechanical properties, further research is needed to establish stronger correlations and to reduce study variations. Exploring non-traditional thrombus components such as leukocytes and neutrophil extracellular traps is vital. Thrombus imaging could provide a practical solution for predicting thrombus composition before endovascular procedures. This review highlights the importance of thrombus composition for enhancing endovascular stroke treatment strategies.

Intravenous Tirofiban Versus Alteplase Before Endovascular Treatment in Acute Ischemic Stroke: A Pooled Analysis of the DEVT and RESCUE BT Trials.

The present study aimed to evaluate the efficacy and safety of intravenous tirofiban versus alteplase before endovascular treatment (EVT) in acute ischemic stroke patients with intracranial large vessel occlusion. This was a post hoc analysis using data from 2 multicenter, randomized trials: the DEVT trial (Direct Endovascular Treatment for Large Vessel Occlusion Stroke) from May 2018 to May 2020 and the RESCUE BT trial (Intravenous Tirofiban Before Endovascular Thrombectomy for Acute Ischemic Stroke) from October 2018 to October 2021. Patients with acute intracranial large vessel occlusion within 4.5 hours from last known well were dichotomized into 2 groups: tirofiban plus EVT versus alteplase bridging with EVT. The primary outcome was functional independence (modified Rankin Scale score of 0-2) at 90 days. Safety outcomes included symptomatic intracranial hemorrhage and 3-month mortality. Multivariable logistic regression (adjusting for baseline systolic blood pressure, occlusion site, onset-to-puncture time, anesthesia, and first choice of EVT) and propensity score overlap weighting (balance in demographic covariates, stroke characteristics, and initial management between groups) were performed. One-hundred and eighteen alteplase-treated patients in the DEVT trial and 98 tirofiban-treated patients in the RESCUE BT trial were included (median age, 70 years; 115 [53.2%] men). The rate of functional independence was 60.2% in the tirofiban group compared with 46.6% in the alteplase group (adjusted odds ratio, 1.25 [95% CI, 0.60-2.63]). Compared with alteplase, tirofiban was not associated with increased risk of symptomatic intracranial hemorrhage (6.8% versus 9.2%; P=0.51) and mortality (17.8% versus 19.4%; P=0.76). The propensity score overlap weighting analyses showed consistent outcomes. Among patients with intracranial large vessel occlusion within 4.5 hours of onset, tirofiban plus EVT was comparable to alteplase bridging with EVT regarding the efficacy and safety outcomes. These findings should be interpreted as preliminary and require confirmation in a randomized trial. URL: https://www.chictr.org.cn; Unique identifiers: ChiCTR-IOR-17013568 and ChiCTR-INR-17014167.

Moyamoya disease in Southeast Asians: genetic and autopsy data, new cases, systematic review, and meta-analysis of all patients from the literature

BackgroundMoyamoya disease (MMD) is a rare disorder causing ischemic and hemorrhagic juvenile stroke. It is associated with the founder susceptibility variant p.R4810K in the RNF213 gene in East Asia. Our aim was to enhance understanding of MMD in so far poorly characterized Southeast Asians and exploring differences with Caucasian Europeans.MethodsBy retrospective analysis of medical records and systematic database search on PubMed for all published cases, we identified Southeast Asian patients with MMD. We extracted and pooled proportions using fixed-effects models. Our own cohort was tested for the East Asian RNF213 founder variant p.R4810K. One of our Southeast Asian patients underwent post-mortem histopathological examination.ResultsThe study cohort comprised 32 Southeast Asians. Mean age at onset in the entire cohort was 32.5 ± 20.3 years (n = 24), 43.4 ± 8.7 years in patients admitted to our center (n = 11), and 23.4 ± 22.4 years in patients from the international literature (n = 13). Female-to-male ratio was 1.6:1. MMD predominantly affected bilateral anterior intracranial vessels. Cerebral ischemia outnumbered transient ischemic attacks (TIAs) and intracranial hemorrhage. TIAs, arterial hypertension and obesity were significantly less frequent in Southeast Asian patients compared to Caucasian Europeans. p.R4810K was absent in all examined Southeast Asians despite of typical histopathological signs of MMD in one autopsy case.ConclusionClinical and histopathological manifestations of MMD in Southeast Asians are similar to those in Caucasian Europeans. The genotype of MMD in Southeast Asians differs from that of most East Asian patients.

Effect of MRI acquisition parameters on accuracy and precision of phase-contrast measurements in a small-lumen vessel phantom

BackgroundPhase-contrast magnetic resonance imaging (PC-MRI) quantifies blood flow and velocity noninvasively. Challenges arise in neurovascular disorders due to small vessels. We evaluated the impact of voxel size, number of signal averages (NSA), and velocity encoding (VENC) on PC-MRI measurement accuracy and precision in a small-lumen vessel phantom.MethodsWe constructed an in vitro model with a constant flow rate using a 2.2-mm inner diameter plastic tube. A reservoir with a weight scale and timer was used as standard reference. Gradient-echo T1 weighted PC-MRI sequence was performed on a 3-T scanner with varying voxel size (2.5, 5.0, 7.5 mm3), NSA (1, 2, 3), and VENC (200, 300, 400 cm/s). We repeated measurements nine times per setting, calculating mean flow rate, maximum velocity, and least detectable difference (LDD).ResultsPC-MRI flow measurements were higher than standard reference values (mean ranging from 7.3 to 9.5 mL/s compared with 6.6 mL/s). Decreased voxel size improved accuracy, reducing flow rate measurements from 9.5 to 7.3 mL/s. The LDD for flow rate and velocity varied between 1 and 5%. The LDD for flow rate decreased with increased voxel size and NSA (p = 0.033 and 0.042). The LDD for velocity decreased with increased voxel size (p < 10-16). No change was observed when VENC varied.ConclusionsPC-MRI overestimated flow. However, it has high precision in a small-vessel phantom with constant flow rate. Improved accuracy was obtained with increasing spatial resolution (smaller voxels). Improved precision was obtained with increasing signal-to-noise ratio (larger voxels and/or higher NSA).Relevance statementPhase-contrast MRI is clinically used in large vessels. To further investigate the possibility of using phase-contrast MRI for smaller intracranial vessels in neurovascular disorders, we need to understand how acquisition parameters affect phase-contrast MRI-measured flow rate and velocity in small vessels.Key points• PC-MRI measures flow and velocity in a small lumen phantom with high precision but overestimates flow rate.• The precision of PC-MRI measurements matches the precision of standard reference for flow rate measurements.• Optimizing PC-MRI settings can enhance accuracy and precision in flow rate and velocity measurements.Graphical

An extended phase graph-based framework for DANTE-SPACE simulations including physiological, temporal, and spatial variations.

The delay alternating with nutation for tailored excitation (DANTE)-sampling perfection with application-optimized contrasts (SPACE) sequence facilitates 3D intracranial vessel wall imaging with simultaneous suppression of blood and CSF. However, the achieved image contrast depends closely on the selected sequence parameters, and the clinical use of the sequence is limited in vivo by observed signal variations in the vessel wall, CSF, and blood. This paper introduces a comprehensive DANTE-SPACE simulation framework, with the aim of providing a better understanding of the underlying contrast mechanisms and facilitating improved parameter selection and contrast optimization. An extended phase graph formalism was developed for efficient spin ensemble simulation of the DANTE-SPACE sequence. Physiological processes such as pulsatile flow velocity variation, varying flow directions, intravoxel velocity variation, diffusion, and effects were included in the framework to represent the mechanisms behind the achieved signal levels accurately. Intravoxel velocity variation improved temporal stability and robustness against small velocity changes. Time-varying pulsatile velocity variation affected CSF simulations, introducing periods of near-zero velocity and partial rephasing. Inclusion of diffusion effects was found to substantially reduce the CSF signal. Blood flow trajectory variations had minor effects, but differences along the trajectory reduced DANTE efficiency in low- areas. Introducing low-velocity pulsatility of both CSF and vessel wall helped explain the in vivo observed signal heterogeneity in both tissue types. The presented simulation framework facilitates a more comprehensive optimization of DANTE-SPACE sequence parameters. Furthermore, the simulation framework helps to explain observed contrasts in acquired data.

Monocyte to high-density lipoprotein ratio as an independent predictor of intracranial atherosclerotic stenosis-related emergency large vessel occlusion

ObjectiveTo evaluate the correlation between the monocyte-to-high-density lipoprotein cholesterol ratio (MHR) and intracranial atherosclerotic stenosis-related emergent large vessel occlusion (ICAS-ELVO) in acute ischemic stroke patients with endovascular thrombectomy. MethodsIncluded in this study were 215 patients who underwent endovascular thrombectomy. They were randomly assigned to training and testing datasets. The patients in training dataset (n=128) were divided into ICAS group (n=65) and embolism group (n=63). MHR was compared between the two groups. According to the cut-off value, patients in testing dataset (n=87) were divided into low-MHR group (n=54) and high-MHR group (n=33). MHR was compared between the two groups. ResultsIn training dataset, the proportion of male patients, diabetic patients and smokers in ICAS group was significantly higher than that in embolism group [(50 (76.9%) vs. 30 (47.6%), P=0.001; 29 (44.6%) vs. 14(22.2%), P=0.007; 37(56.9%) vs. 14 (22.2%), P=0.001; 37 (56.9%) vs. 14 (22.2%), P=0.001], while the mean age and the proportion of patients with coronary heart disease (CHD), stroke and atrial fibrillation were significantly lower [(64.74±9.13 vs. 71.38±13.34, P=0.001; 6 (9.2%) vs. 14 (22.2%), P=0.043; 12 (18.5%) vs. 22 (34.9%), P=0.035; 5 (7.7%)vs. 56 (88.9%), P<0.001)]. The laboratory test results showed that monocyte count was significantly higher and high-density lipoprotein level was significantly lower in ICAS group than those in embolism group (0.61±0.26 vs. 0.45±0.13, P=0.001; 1.17±0.28 vs. 1.37±0.27, P=0.001). MHR in ICAS group was significantly higher than that in embolism group (0.55±0.26 vs. 0.34±0.11, P=0.001). In training set, MHR was found to be an independent predictor for the occurrence of ICAS-ELVO with an adjusted OR of 2.39 (95%CI 1.29–4.48, P=0.006). ROC curve analysis showed that the area under the curve (AUC) of MHR was 0.8 (95% CI, 0.72–0.87, p < 0.001), with a sensitivity of 0.60 and a specificity of 0.873. The optimal cut-off value of the MHR level was 0.46. In testing dataset, the rate of ICAS-ELVO in higher quartile was significantly higher than that in the lower quartile (81.8% vs. 33.3%, P<0.001). Patients with a low MHR had a higher rate of cerebral hemorrhagic than those with a high MHR. ConclusionMHR was associated with ICAS-ELVO in acute ischemic stroke patients with endovascular thrombectomy, and the higher level of MHR does benefit to differentiate ICAS from intracranial embolism, suggesting that MHR may prove to be an independent predictor for ICAS-ELVO.

The short-term outcome of intracranial stenosis with distal thrombosis treated with balloon-assisted tracking.

Treating intracranial stenosis with distal thrombosis (IS&DT) using traditional mechanical thrombectomy (MT) techniques has proven challenging. This study aimed to summarize the experience of utilizing the balloon-assisted tracking (BAT) technique for IS&DT. Demographic and morphologic characteristics of patients with IS&DT were collected for this study. The BAT technique, involving a half-deflated balloon outside the intermediate catheter tip, was used in all patients to navigate through the proximal stenosis. Various parameters were recorded, including the sequence of vascular reperfusion, the puncture-to-reperfusion time (PRT), the residual stenosis rate, and the occurrence of re-occlusion. The thrombolysis in cerebral infarction (TICI) scale was used to assess the reperfusion of intracranial vessels, with a TICI score of ≥2b considered as successful perfusion. The clinical status of patients was evaluated at three time points: pre-procedure, post-procedure, and at discharge using the modified Rankin score (mRS). In this study, a total of 10 patients were diagnosed with IS&DT, consisting of 9 male patients (90.0%) and 1 female patient (10.0%). The patients' mean age was 63.10 years (ranging from 29 to 79 years). The mean National Institute of Health Stroke Scale (NIHSS) score before treatment was 24.3 (ranging from 12 to 40), indicating the severity of their condition. Following the procedure, all patients achieved successful reperfusion with a thrombolysis in cerebral infarction (TICI) score of ≥2b. The average puncture-to-reperfusion time (PRT) was 51.8 min (ranging from 25 to 100 min), indicating the time taken for the procedure. During the perioperative period, three patients (30.0%) experienced complications. One patient had hemorrhage, while two patients had contrast extravasation. Among these cases, only the patient with hemorrhage (10%) suffered from a permanent neurological function deficit. At discharge, the patient's condition showed improvement. The mean NIHSS score decreased to 13.2 (ranging from 1 to 34), indicating a positive response to treatment. The mean mRS score at discharge was 3.2 (ranging from 1 to 5), showing some level of functional improvement. In conclusion, the use of the balloon-assisted tracking (BAT) technique for treating intracranial stenosis with distal thrombosis (IS&DT) showed promising results. However, a moderate rate of perioperative complications was observed, warranting further investigation and refinement of the procedure.

Clinico-radiological features of intracranial atherosclerosis-related large vessel occlusion prior to endovascular treatment

The identification of large vessel occlusion with underlying intracranial atherosclerotic disease (ICAS-LVO) before endovascular treatment (EVT) continues to be a challenge. We aimed to analyze baseline clinical-radiological features associated with ICAS-LVO that could lead to a prompt identification. We performed a retrospective cross-sectional study of consecutive patients with stroke treated with EVT from January 2020 to April 2022. We included anterior LVO involving intracranial internal carotid artery and middle cerebral artery. We analyzed baseline clinical and radiological variables associated with ICAS-LVO and evaluated the diagnostic value of a multivariate logistic regression model to identify ICAS-LVO before EVT. ICAS-LVO was defined as presence of angiographic residual stenosis or a trend to re-occlusion during EVT procedure. A total of 338 patients were included in the study. Of them, 28 patients (8.3%) presented with ICAS-LVO. After adjusting for confounders, absence of atrial fibrillation (OR 9.33, 95% CI 1.11–78.42; p = 0.040), lower hypoperfusion intensity ratio (HIR [Tmax > 10 s/Tmax > 6 s ratio], (OR 0.69, 95% CI 0.50–0.95; p = 0.025), symptomatic intracranial artery calcification (IAC, OR .15, 95% CI 1.64–26.42, p = 0.006), a more proximal occlusion (ICA, MCA-M1: OR 4.00, 95% CI 1.23–13.03; p = 0.021), and smoking (OR 2.91, 95% CI 1.08–7.90; p = 0.035) were associated with ICAS-LVO. The clinico-radiological model showed an overall well capability to identify ICAS-LVO (AUC = 0.88, 95% CI 0.83–0.94; p < 0.001). In conclusion, a combination of clinical and radiological features available before EVT can help to identify an ICAS-LVO. This approach could be useful to perform a rapid assessment of underlying etiology and suggest specific pathophysiology-based measures. Prospective studies are needed to validate these findings in other populations.

Abstract TP221: Progression of Intracranial Artery Stenosis and Cerebral Small Vessel Disease and Associations Between the Two Entities: A Prospective Community-Based Cohort Study

Background: Both intracranial artery stenosis (ICAS) and cerebral small vessel disease (CSVD) can cause heavy socioeconomic burdens. However, their longitudinal changes remain controversial. To investigate the risk factors for ICAS and CSVD progression and their associations in a community population. Methods: This longitudinal analysis included 756 participants who underwent both baseline and follow-up brain magnetic resonance imaging (MRI) and magnetic resonance angiography from Shunyi cohort. The follow-up duration was 5.58±0.49 years. Incident ICAS was defined as new stenosis occurring in at least one artery or increased severity of the original artery stenosis. CSVD markers included lacunes, cerebral microbleeds (CMB), and white matter hyperintensities (WMH). Results: Of the 756 participants (aged 53.7±8.0 years, 34.9% men), 8.5% had incident ICAS. Body mass index (BMI) and diabetes mellitus are independent risk factors for ICAS. Hypertension is an independent risk factor for incident lacunes and CMB, whereas WMH progression is primarily affected by BMI. Higher LDL cholesterol level independently protects against WMH progression. Baseline ICAS burden predicted an increased risk of incident lacunes (odds ratio [OR] = 2.17, 95% confidence interval [CI] = 1.10-4.29, p = 0.025) after adjusting for age, sex, follow-up time, vascular risk factors, and baseline lacunes burden. Incident ICAS was also significantly associated with incident lacunes (OR = 3.29, 95% CI = 1.61-6.72, p = 0.001). No significant correlation was identified between ICAS and CMB or WMH. Conclusions: Patients with ICAS and CSVD progression had different modifiable risk factor profiles. The disparate association between ICAS and progressions of different MRI markers of CSVD imply vital differences of their underline mechanism.

Abstract WP179: Clinical Outcomes in Acute Stroke in Patients Undergoing Emergency Intracranial Stenting Receiving IV Thrombolysis

Background: Stent-retriever thrombectomy is the first-line therapy for acute stroke with intracranial large vessel occlusion. In cases of stent-retriever thrombectomy failure, rescue stent angioplasty might be the sole option for achieving permanent recanalization. This study aims to evaluate the safety of combined intracranial vessel stent placement and thrombolysis. Methods: We conducted a retrospective analysis of patients with large vessel occlusion who underwent rescue stent angioplasty after stent-retriever thrombectomy between 2012 and 2023 in 8 neurovascular centers. We defined two binary outcomes: (1) functional clinical outcome (modified Rankin Scale 0-2) and (2) early symptomatic intracerebral hemorrhage (sICH). Clinical outcomes were assessed using uni- and multivariable logistic regression models. Results: A total of 216 patients were included, with target vessels located within the anterior circulation (133; 63.4%) and posterior circulation (79; 36.6%). Among patients who underwent emergency intracranial stenting, 66 (30.6%) received intravenous thrombolytic treatment. In multivariate logistic regression analysis, adjusted for age, gender, baseline NIHSS, target vessel, time to recanalization, number of passes including, and type of antiplatelet therapy, intravenous thrombolytic therapy was not associated with symptomatic ICH (odds ratio (OR) 1.05, 95% confidence interval (CI) 0.27-4.14, p=0.9502), but it was associated with a functional clinical outcome at 90 days (OR 3.39, 95% CI 1.11-10.43, p=0.0325). Conclusions: The use of rescue stent angioplasty can be considered after unsuccessful stent-retriever thrombectomy, along with intravenous thrombolytic therapy. Patients receiving intravenous thrombolytic therapy before the procedure exhibited higher rates of good functional outcomes.

Abstract WMP9: Comparative Analysis of Endovascular Treatment Outcomes in Acute Large Vessel Occlusion Strokes: Intracranial Atherosclerotic vs. Non- Intracranial Atherosclerotic Occlusions

Introduction: Intracranial atherosclerotic disease (ICAD) is a common cause of ischemic stroke worldwide. We assessed the clinical outcomes of endovascular treatment in acute large vessel occlusion (LVO) strokes caused by ICAD and compared them with large vessel occlusion strokes not associated with intracranial atherosclerosis (non-ICAD LVO). Methods: Our study comprised 1390 adult patients diagnosed with LVO stroke that underwent endovascular therapy at Rhode Island Hospital from July 2015 to March 2023 and data collected retrospectively. Among these, 68 patients exhibited Intracranial Atherosclerotic Disease Large Vessel Occlusion (ICADLVO), while 1322 individuals were categorized as non-ICADLVO. In the ICADLVO group, 23 out of 68 patients underwent angioplasty, whereas 38 patients received stenting. We aim to compare treatment outcomes, including recurrent in-hospital large vessel occlusion, disability, and mortality between these two distinct groups, while also assessing demographic characteristics and medical risk factors. T-Test, Chi square and fisher’s exact tests were used for the comparison of groups. Results: The study findings highlight significant differences between the ICADLVO group and the non-ICADLVO group. The ICADLVO group had younger age (mean 66.6 ± 12.64 vs. 71.92 ± 14.56, p &lt; 0.001) , higher proportion of individuals with Asian ethnicity (5.2% vs. 0.8%, p = 0.019), higher incidence of prior strokes (43.3% vs. 23.9%, p=0.000), higher prevalence of smokers (35.6% vs. 22.7%, p = 0.022), and a lower association with known atrial fibrillation (23.9% vs. 42.3%, p=0.003) compared to the non-ICADLVO group. Additionally, the ICADLVO group had a higher occurrence of recurrent large vessel occlusion during hospitalization (11.8% vs. 4%, p = 0.008). This analysis finds no significant difference in good 90-dayfunctional outcome (mRS &lt;= 2) between the ICADLVO and NON-ICADLVO groups (OR = 0.62, 95% CI 0.34-1.13, p=0.118). Conclusion: Our study showed a higher incidence of recurrent large vessel occlusion during hospitalization in the ICADLVO group following endovascular therapy. However, we did not observe any statistically significant differences in long-term outcomes, including measures of disability and mortality.

Abstract TMP51: Clinical Factors Associated With Enlarged Perivascular Spaces in a US Population of Caucasian Descent

Introduction: Enlarged Perivascular Spaces (EPVS), characterized by distinct cerebrospinal fluid-filled structures surrounding intracranial vessels, have garnered growing attention concerning brain aging and cerebrovascular disorders. This study investigates the associations between EPVS and a spectrum of clinical factors and conditions in a large community-based sample in the northeastern United States. Method: This research was conducted on a subset of the Geisinger DiscovEHR Initiative Cohort. The total numbers of EPVS were categorized into five grades (0-4) in centrum semiovale and basal ganglia regions. A comparison was established between patients with EPVS and a propensity-score-matched cohort devoid of EPVS. Matching factors included age, gender, body mass index, and hypertension. Results: Among 3054 randomly selected participants (mean age 67.5 years, 57.4% women), 1465 (47.9%, mean age 69.6 years, 58% women) exhibited EPVS in their brain imaging. The presence of EPVS was linked to cerebral aneurysm (OR, 2.40; 95% CI, 1.5-4.0), heart failure (OR, 2.0; 95% CI, 1.5-2.8), peripheral vascular disease (OR, 1.5; 95% CI, 1.1-2.15), Parkinson's Disease (OR, 1.9; 95% CI, 1.2-3.1), history of ischemic stroke (OR, 1.18; 95% CI, 1.0-1.4), non-central nervous system malignancies (OR, 1.4; 95% CI, 1.1-2.0), smoking (OR, 1.3; 95% CI, 1.0-1.6), and warfarin use (OR, 0.76; 95% CI, 0.6-0.9). Higher scales of EPVS were notably associated with obstructive sleep apnea (OR, 1.9; 95% CI, 1.0-3.8) and hypertension (OR, 3.1; 95% CI, 1.1-9.9). Conclusion: EPVS presence and severity may be associated with several vascular risk factors, providing potential avenues for risk assessment and further research.