Posterior Cerebral Research Articles

Angiographic features and progression risk factors in children with asymptomatic moyamoya disease

ObjectiveThis study aims to explore the potential contribution of angiographic characteristics in the increased stroke risk among pediatric patients.MethodsThis study retrospectively enrolled pediatric patients with ischemic, hemorrhagic, and asymptomatic moyamoya disease. Their hemispheres were categorized into five groups for the analysis of angiographic characteristics, which included Suzuki’s stage, moyamoya vessels, lenticulostriate artery, thalamotuberal artery, thalamoperforating artery, anterior choroidal arteries, posterior choroidal arteries, and posterior cerebral artery involvement.ResultsTwo hundred and nineteen pediatric patients with four hundred and thirty-eight hemispheres were enrolled. There was no significant difference in collateral dilatation between asymptomatic and hemorrhagic hemispheres. However, asymptomatic hemispheres had significantly lower incidence of posterior cerebral artery involvement and Suzuki’s stage compared to hemorrhagic (p = 0.008, p = 0.004) and ischemic hemispheres (p = 0.026, p < 0.001). Multivariate analysis revealed that Suzuki’s stage (p = 0.002, 95% CI 1.261–2.867) is a risk factor for ischemia, while age (p < 0.001, 95% CI 0.712–2.014) and posterior cerebral artery involvement (p = 0.037, 95% CI 0.087–13.377) are risk factors for hemorrhage.InterpretationAngiographic features in children with asymptomatic moyamoya disease resemble those observed in the hemorrhagic pediatric patients, indicating that greater attention should be focused on the risk of future hemorrhage in these patients, rather than on ischemia. Additionally, studies have demonstrated a correlation between posterior cerebral artery involvement and age with the incidence of hemorrhage. Monitoring angiographic characteristics may assist in tracking the transition from asymptomatic to symptomatic hemispheres.

Macrovascular blood flow and microvascular cerebrovascular reactivity are regionally coupled in adolescence.

Cerebrovascular imaging assessments are particularly challenging in adolescent cohorts, where not all modalities are appropriate, and rapid brain maturation alters hemodynamics at both macro- and microvascular scales. In a preliminary sample of healthy adolescents (n = 12, 8-25 years), we investigated relationships between 4D flow MRI-derived blood velocity and blood flow in bilateral anterior, middle, and posterior cerebral arteries and BOLD cerebrovascular reactivity (CVR) in associated vascular territories. As hypothesized, higher velocities in large arteries are associated with an earlier response to a vasodilatory stimulus (cerebrovascular reactivity delay) in the downstream territory. Higher blood flow through these arteries is associated with a larger BOLD response to a vasodilatory stimulus (cerebrovascular reactivity amplitude) in the associated territory. These trends are consistent in a case study of adult moyamoya disease. In our small adolescent cohort, macrovascular-microvascular relationships for velocity/delay and flow/CVR change with age, though underlying mechanisms are unclear. Our work emphasizes the need to better characterize this key stage of human brain development, when cerebrovascular hemodynamics are changing, and standard imaging methods offer limited insight into these processes. We provide important normative data for future comparisons in pathology, where combining macro- and microvascular assessments may better help us prevent, stratify, and treat cerebrovascular disease.

Unilateral double fenestration of the same posterior cerebral artery at P1 segment: first cadaveric case report and literature review.

Arterial fenestration involves an artery emerging from the same embryological origin, with its lumen divided into two channels that subsequently rejoin. This kind of vascular variant has consequences, such as focal defects in the histologic layers of the arteries, hemodynamic stress, and challenges for endovascular procedures in the management of vascular pathologies. The main objective of this work is to present a rare vascular variant, a double fenestration of the same P1 segment of a cadaveric specimen, and a literature review of these kind of vascular variants. A cadaveric study was performed in which 20 central nervous system specimens, from patients without neurological pathology obtained as a donation from the National Institute of Legal Medicine and Forensic Sciences, were dissected for educational and research purposes. In one specimen it was found a double fenestration of the right P1 segment, associated with a single fenestration of the right superior cerebellar artery. Few cases of posterior circulation fenestration, beyond the vertebrobasilar trunk are reported in the literature, with limited understanding of the potential hemodynamic consequences thereof. In all the literature available, only eight cadaveric cases of P1 segment fenestration are documented, often linked with other central nervous system vascular abnormalities such as aneurysms or duplications. There is a single report of unilateral double P1 segment fenestration in a living patient. To our knowledge, this is the second case reported in the literature on this specific anatomical anomaly, and the first such report in a cadaver.

Clinical efficacy of DSA-based features in predicting outcomes of acupuncture intervention on upper limb dysfunction following ischemic stroke

Background and objectivesThis study aimed to employ machine learning techniques to predict the clinical efficacy of acupuncture as an intervention for patients with upper limb motor dysfunction following ischemic stroke, as well as to assess its potential utility in clinical practice.MethodsMedical records and digital subtraction angiography (DSA) imaging data were collected from 735 ischemic stroke patients with upper limb motor dysfunction who were treated with standardized acupuncture at two hospitals. Following the initial screening, 314 patient datasets that met the inclusion criteria were selected. We applied three deep-learning algorithms (YOLOX, FasterRCNN, and TOOD) to develop the object detection model. Object detection results pertaining to the cerebral vessels were integrated into a clinical efficacy prediction model (random forest). This model aimed to classify patient responses to acupuncture treatment. Finally, the accuracies and discriminative capabilities of the prediction models were assessed.ResultsThe object detection model achieved an optimal recognition rate, The mean average precisions of YOLOX, TOOD, and FasterRCNN were 0.61, 0.7, and 0.68, respectively. The prediction accuracy of the clinical efficacy model reached 93.6%, with all three-treatment response classification area under the curves (AUCs) exceeding 0.95. Feature extraction using the prediction model highlighted the significant influence of various cerebral vascular stenosis sites within the internal carotid artery (ICA) on prediction outcomes. Specifically, the initial and C1 segments of the ICA had the highest predictive weights among all stenosis sites. Additionally, stenosis of the middle cerebral, anterior cerebral, and posterior cerebral arteries exerted a notable influence on the predictions. In contrast, the stenosis sites within the vertebral artery exhibited minimal impact on the model's predictive abilities.ConclusionsResults underscore the substantial predictive influence of each cerebral vascular stenosis site within the ICA, with the initial and C1 segments being pivotal predictors.

An Interventional Quandary—Clipping vs Coiling vs STA-MCA Bypass in a Ruptured Basilar Tip Aneurysm with Bilateral ICA Stenosis: A Rare Case Report and a Comprehensive Review

Our primary goal is to report a detailed case outlining the clinical and radiological characteristics of an extremely rare condition: bilateral internal carotid artery (ICA) stenosis with ruptured basilar tip aneurysm, and bilateral posterior cerebral arteries (PCAs) arising from the sac, treatment options, as well as its outcome. We searched the PUBMED database from 1980 to 2023 for similar case reports. Among seven similar cases found, two were conservatively managed, focusing on reducing intracranial pressure (ICP). One out of two survived, while one ended in fatality. In the other five cases, interventions (endovascular in four/STA-MCA (superficial temporal artery–middle cerebral artery) bypass in one) were pursued, resulting in significant recovery and discharge. Dealing with such complex cases with uncommon pathoanatomy poses treatment challenges due to their hemodynamics and the risk of collateral flow cessation despite multiple available treatment options.

Association Between the Fetal-Type Posterior Cerebral Artery and Hypertensive Thalamic Hemorrhage.

This study investigated the association between the fetal-type posterior cerebral artery (FTP) and hypertensive thalamic hemorrhage (HTH). Patients with hypertension who met the admission criteria between January 2020 and August 2022 were retrospectively analyzed and divided into the HTH and non-HTH groups based on the presence or absence of thalamic hemorrhage, respectively. In addition to whether the variable was an FTP, other variables with unbalanced distributions between the two groups were used as matching factors for 1:1 propensity score matching, and other variables that were not used as matching factors were used as covariates for conditional logistic regression. A total of 722 patients were included in the study, with 115 in the HTH group and 607 in the non-HTH group. After propensity score matching, 114 patients were included in both groups. The multivariate logistic regression analysis showed that the FTP (p = 0.003, odds ratio [OR]: 2.712, 95% confidence interval [CI]: 1.407-5.225) and homocysteine levels (p = 0.007; OR: 1.051; 95% CI: 1.014-1.089) were significantly correlated with the occurrence of HTH. The incidence of FTP is not low, and it is an independent risk factor for HTH. Early recognition and appropriate monitoring are warranted for cases of FTP.

Circle of Willis and Its Anatomical Relevance

The Circle of Willis is an arterial network located at the base of the brain, formed by the interconnection of the anterior, middle, and posterior cerebral arteries, along with the anterior and posterior communicating arteries. It connects the internal carotid arteries to the vertebral arteries, allowing the distribution of cerebral blood flow. Its significance lies in its ability to offer an alternative pathway in cases of arterial obstruction, helping to prevent cerebral ischemia. However, anatomical variations of this structure are common, and only 20% to 25% of the population has a "complete" or symmetrical configuration. Such variations can influence the risk of cerebrovascular diseases, such as stroke, as they may compromise the efficiency of the compensatory mechanism. These anatomical variations have a direct impact on the diagnosis and treatment of neurological conditions. The integrity of the Circle of Willis can influence the severity of symptoms in cases of ischemic strokes, as well as affect aneurysm formation and its clinical implications. Advances in imaging techniques, such as CT angiography and magnetic resonance imaging, have enabled more accurate diagnoses and the development of more effective treatments for conditions associated with the Circle of Willis, making its anatomical understanding essential for the prevention and management of cerebrovascular diseases.

Quantifying neurovascular coupling through a concurrent assessment of arterial, capillary, and neuronal activation in humans: A multimodal EEG-fNIRS-TCD investigation

BackgroundThis study explored a novel multimodal neuroimaging approach to assess neurovascular coupling (NVC) in humans using electroencephalography (EEG), functional near-infrared spectroscopy (fNIRS), and transcranial Doppler ultrasound (TCD). MethodsFifteen participants (nine females; age 19–32) completed concurrent EEG-fNIRS-TCD imaging during motor (finger tapping) and visual (“Where's Waldo?”) tasks, with synchronized monitoring of blood pressure, capnography, and heart rate. fNIRS assessed microvascular oxygenation within the frontal, motor, parietal, and occipital cortices, while the middle and posterior cerebral arteries (MCA/PCA) were insonated using TCD. A 16-channel EEG set-up was placed according to the 10–20 system. Wilcoxon signed-rank tests were used to compare physiological responses between the active and resting phases of the tasks, while cross-correlations with zero legs compared cerebral and systemic hemodynamic responses across both tasks. ResultsTime-frequency analysis demonstrated a reduction in alpha and low beta band power in electrodes C3/C4 during finger tapping (p<0.045) and all electrodes during the Waldo task (all p<0.001). During Waldo, cross-correlation analysis demonstrated the change in oxygenated hemoglobin and cerebral blood velocity had a moderate-to-strong negative correlation with systemic physiological influences, highlighting the measured change resulted from neuronal input. Deoxygenated hemoglobin displayed the greatest negative cross-correlation with the MCA/PCA within the motor cortices and visual during the motor and visual tasks, respectively (range:0.54, -0.82). ConclusionsThis investigation demonstrated the feasibility of the proposed EEG-fNIRS-TCD response to comprehensively assess the NVC response within human, specifically quantifying the real-time temporal synchrony between neuronal activation (EEG), microvascular oxygenation changes (fNIRS), and conduit artery velocity alterations (TCD).

Moyamoya disease: insights into the clinical implications of the RNF213 gene

Moyamoya disease (MMD) is a rare cerebrovascular disorder characterized by progressive stenosis of the terminal internal carotid arteries and the formation of compensatory collateral vessels, which appear as a “puff of smoke” on cerebral angiography. It is a significant cause of stroke in East Asia, with an incidence of 0.5 to 1.5 cases per 100,000 people annually. The etiology of MMD remains unclear; however, the identification of the RNF213 gene, particularly the R4810K variant, as a major susceptibility factor among the East Asian population, has provided crucial insights into the disease's pathophysiology and clinical manifestations. MMD typically presents with transient ischemic attacks, ischemic and hemorrhagic strokes, seizures, headaches, and cognitive deficits. Diagnostic criteria have evolved to emphasize advanced imaging techniques. Pathological features include fibrocellular intimal thickening, irregular undulation of the elastic lamina, and the formation of moyamoya vessels. The mutation in the RNF213 gene impairs the degradation of proteins involved in vessel development, leading to abnormal angiogenesis. Genotype-phenotype studies indicate that the RNF213 variant is associated with an earlier onset, transient ischemic attacks, infarctions, and involvement of the posterior cerebral artery, although its effects vary between regions. Additionally, the homozygous RNF213 variant consistently correlates with an earlier age of onset and a higher risk of cerebral infarction. However, further research is necessary to fully understand its long-term impacts and its relationship with revascularization outcomes. Ongoing research is crucial to fully comprehend the pathophysiology and genetics of MMD, improve prognostic predictions, and develop novel therapies.

Successfully intravenous thrombolytic therapy in systemic lupus erythematosus-related ischemic stroke: A case report.

Stroke is a relatively frequent complication occurring in patients with systemic lupus erythematosus (SLE). The increasing number of patients with Ischemic Stroke secondary to SLE aroused the clinician's concern. SLE thrombosis markers, diagnostic high-resolution magnetic resonance image (HR-MRI), and therapeutic interventions for acute ischemic stroke were recently coming into focus perspectives from the field. A 42-year-old female with slurred speech and numbness in her left limb was admitted to our hospital. Magnetic resonance imaging (MRI) revealed right thalamic infarction with diffusion-weighted lesions. Prior to admission, the patient had a National Institute of Health Stroke Scale (NIHSS) score of 3. In light of the clinical manifestation, the American Heart Association/American Stroke Association (AHA/ASA) Guidelines for Intravenous Thrombolysis in Acute Ischemic Stroke (2019) should be referred to. The patient was treated with thrombolytic alteplase (rt-PA). The patient was hospitalized for 2 weeks and discharged after his symptoms improved. After thrombolysis, the NIHSS score of the patient decreased to zero. The computed tomography scan was reexamined 24 hours later, and no acute changes or hemorrhage were identified in the infarcted area. Subsequent imaging and serological analyses indicated that HR-MRI of the responsible vessel was negative, but the infarction in this patient was still regarded as being caused by vasculitis of the right posterior cerebral artery in the region supplying the thalamus. This is the first case of successful intravenous thrombolytic therapy with rt-PA in a patient with SLE secondary to stroke with an NIHSS score of 3. This provides further evidence for expanding the reference of indications with rt-PA intravenous thrombolysis.

Effect of prolonged sitting on dynamic cerebral autoregulation in the anterior and posterior cerebral circulations.

Individuals who experience prolonged sitting daily are reported to be at risk of developing cerebrovascular disease, which is associated, in part, with attenuation in cerebral blood flow regulation. However, the effect of prolonged sitting on dynamic cerebral autoregulation (dCA), a crucial mechanism of cerebral blood flow regulation, remains unclear. Additionally, cerebrovascular disease occurs heterogeneously within cerebral arteries. The purpose of the present study was to examine the hypothesis that prolonged sitting attenuates dCA in the cerebral circulation heterogeneously. Twelve young, healthy participants were instructed to maintain a seated position for 4h without moving their lower limbs. Mean arterial pressure and mean blood velocities of the middle cerebral artery (MCA Vm) and the posterior cerebral artery (PCA Vm) were measured continuously throughout the experiment. The dCA was assessed using transfer function analysis (TFA) with mean arterial pressure and either MCA Vm or PCA Vm. In the MCA, very low-frequency TFA-normalized gain decreased significantly during 4h of prolonged sitting (P=0.029), indicating an improvement rather than attenuation in dCA, despite a significant reduction in MCA Vm after 4h of continuous sitting (P=0.039). In the PCA, PCA Vm remained stable throughout the 4h sitting period (P=0.923), and all TFA parameters remained unchanged throughout the 4h of sitting. Contrary to our hypothesis, these results suggest that the dCA in both the MCA and the PCA was well stabilized in healthy young individuals during acute prolonged sitting.

The Neck-Crossing Technique Using the Low-Profile Distal Access Catheter in Flow Diverter Placement for Dissecting Posterior Cerebral Artery Aneurysm: A Case Report

AbstractWe report a case in which a novel distal access catheter proved successful in the placement of a flow diverter for a challenging distal cerebral artery lesion. We discuss the advantages and pitfalls of this technique and considerations for its use. A 74-year-old female presented with intermittent headaches, and was diagnosed with a dissecting aneurysm at the proximal right posterior cerebral artery with a sharp bleb, measuring 9.8 mm in diameter. Given the complex vascular anatomy, stent-assisted coil embolization was initially considered but deemed high risk for dual catheter for jailing technique with 6-Fr size guiding catheter due to the tortuosity and stenosis of the parent vessel. Therefore, we opted for flow diverter treatment, which presented its challenges during delivery. By employing a low-profile distal access catheter, Phenom Plus (outer diameter: 4.2-Fr. inner diameter: 1.13 mm; Medtronic, Minneapolis, Minnesota, United States), with a minimal ledge between it and the delivery catheter, Phenom 27 (outer diameter: 2.8-Fr, 0.91 mm; Medtronic), we successfully crossed the neck of the aneurysm with Phenom Plus and placed the flow diverter. While acknowledging potential risks, this case demonstrates the value of the neck-crossing technique using a low-profile distal access catheter as an alternative option for treating challenging peripheral artery aneurysms with flow diverters. This technique offers promise in specific situations where conventional methods pose challenges.

The relationships between age, sex and exercise intensity on cerebral artery haemodynamics during isometric handgrip exercise.

Age and sex may alter the cerebral blood flow (CBF) responses to acute isometric exercise, via associated elevations in mean arterial pressure (MAP) and sympathetic activation. Our aim was to determine the relationships between age, sex and exercise intensity on cerebrovascular responses to isometric handgrip exercise. In 78 healthy adults (18-80 years, N=42 female), cerebrovascular responses were assessed during two minute isometric exercise bouts at three intensities (15, 30, 45% maximal voluntary contraction). Intracranial responses of the middle cerebral artery (MCA) and posterior cerebral artery (PCA) velocity (v) were measured using transcranial Doppler ultrasound. Extracranial responses of the internal carotid artery (ICA) and vertebral artery (VA) were assessed using Duplex ultrasound. Cardiopulmonary haemodynamic and neural parameters were measured throughout, including muscle sympathetic nerve activity, end-tidal carbon dioxide, and MAP. There were significant positive relationships between exercise intensity and the cerebral responses of the MCAv (P<0.001) and PCAv (P=0.005). There were no effects of intensity on ICA and VA responses (P>0.05), despite intensity-dependent increases in MAP (P<0.001). The increased MCAv response to exercise was blunted with advancing age (P=0.01) with no influence of sex (P=0.86). The present study provides data on age, sex and intensity specific relationships with intracranial and extracranial cerebrovascular responses to isometric exercise. Despite similar ICA, VA, and PCA responses, MCAv responses were attenuated with advancing age during handgrip exercise with no sex dependent influence. Further, intracranial responses were intensity dependent, whereas extracranial blood flow, shear-stress and velocity responses were similarly increased at all intensities during handgrip exercise.

Endovascular therapy versus medical management in isolated posterior cerebral artery acute ischemic stroke: A multinational multicenter propensity score-weighted study.

Despite the proven effectiveness of endovascular therapy (EVT) in acute ischemic strokes (AIS) involving anterior circulation large vessel occlusions, isolated posterior cerebral artery (PCA) occlusions (iPCAo) remain underexplored in clinical trials. This study investigates the comparative effectiveness and safety of EVT against medical management (MM) in patients with iPCAo. This multinational, multicenter propensity score-weighted study analyzed data from the Multicenter Analysis of primary Distal medium vessel occlusions: effect of Mechanical Thrombectomy (MAD-MT) registry, involving 37 centers across North America, Asia, and Europe. We included iPCAo patients treated with either EVT or MM. The primary outcome was the modified Rankin Scale (mRS) at 90 days, with secondary outcomes including functional independence, mortality, and safety profiles such as hemorrhagic complications. A total of 177 patients were analyzed (88 MM and 89 EVT). EVT showed a statistically significant improvement in 90-day mRS scores (OR = 0.55, 95% CI = 0.30-1.00, p = 0.048), functional independence (OR = 2.52, 95% CI = 1.02-6.20, p = 0.045), and a reduction in 90-day mortality (OR = 0.12, 95% CI = 0.03-0.54, p = 0.006) compared to MM. Hemorrhagic complications were not significantly different between the groups. EVT for iPCAo is associated with better neurological outcomes and lower mortality compared to MM, without an increased risk of hemorrhagic complications. Nevertheless, these results should be interpreted with caution due to the study's observational design. The findings are hypothesis-generating and highlight the need for future randomized controlled trials to confirm these observations and establish definitive treatment guidelines for this patient population.

The relationship between the state of cerebral blood flow and volemic status in patients with ischemic stroke in the acute period

The objective was to assess the relationship between the state of cerebral blood flow and volemic status in patients with acute ischemic stroke using the laboratory and instrumental parameters.Materials and methods. 51 patients with newly diagnosed ischemic stroke confirmed by MSCT/MRI of the brain were examined within less than 24 hours from the onset of the disease, and 20 practically healthy individuals (control group). To determine cerebral blood flow, the hemodynamic parameters of transcranial Doppler imaging were used: blood flow rates (maximum systolic, diastolic, averaged over time), Gosling’s pulsatility index and Purcelo’s index of peripheral resistance in the anterior, posterior, middle and main cerebral arteries from the affected and intact sides. Volemic status was assessed using laboratory (serum sodium and brain natriuretic peptide NT-pro-BNP) and instrumental parameters (echocardiography – end-diastolic volume of the left ventricle, left ventricular ejection fraction, diameter and degree of collapse on inhalation of the inferior vena cava).Results. Deterioration of the state of cerebral blood flow by speed indicators and an increase in the resistance parameters of the vascular wall was noted in the studied affected and intact arteries against the background of violations of the volemic status by the level of brain natriuretic peptide, end-diastolic volume of the left ventricle, diameter of the inferior vena cava, left ventricular ejection fraction and degree of collapse of the inferior vena cava. There is a correlation of vascular wall resistance parameters with laboratory and instrumental indicators of volemia, since both the development of deficiency and volume overload negatively affect cerebral perfusion.Conclusions. The cerebral blood flow parameters are correlated with the volemic status of patients with ischemic stroke in the acute period.

Ischemic stroke due to dissection of the posterior cerebral artery in a patient with polycystic kidney disease

Polycystic kidney disease (PKD) is a genetic condition clinically manifested by the formation of multiple cysts in the kidneys, liver and pancreas, as well as cardiovascular pathology. One of the rare complications of PKD is the development of dissections of the aorta, coronary and cerebral arteries.This article presents a clinical case of ischemic stroke due to dissection of the posterior cerebral artery in a young patient with PKD who had a history of recurrent bleeding in the deep parts of both cerebral hemispheres.

More severe cerebral small vessel disease associated with poor leptomeningeal collaterals in symptomatic intracranial atherosclerotic stenosis.

We investigated the association between cerebral small vessel disease (CSVD) and ipsilateral leptomeningeal collateral (LMC) status in patients with symptomatic intracranial atherosclerotic stenosis (sICAS). In 108 patients with 50-99% symptomatic intracranial internal carotid artery or M1 middle cerebral artery stenosis, 4 CSVD imaging markers (lacunes, cerebral microbleeds, enlarged perivascular spaces [EPVSs], and white matter hyperintensities [WMHs]) were assessed in MRI. Score of 0 or 1 was assigned to each marker and added up as a summary CSVD score (ranging 0-4) to reflect an overall CSVD burden. Ipsilateral LMC status was assessed by determining the laterality of distal vessels in anterior and posterior cerebral artery territories on CT angiography. Moderate-to-severe EPVSs (adjusted odds ratio [aOR] = 4.15; p = 0.031) and WMHs (aOR = 5.90; p = 0.010), and higher summary CSVD score (aOR = 1.66; p = 0.030) were independently associated with poor LMCs. There was significant interaction between stenosis percentage in sICAS and summary CSVD score on poor LMCs (p = 0.022 for interaction), when higher CSVD score was significantly associated with poor LMCs in patients with severe sICAS (aOR = 2.84; p = 0.011) but not in those with moderate sICAS. The findings indicated possibly adverse effect of CSVD on the recruitment or development of LMCs in sICAS patients, especially in patients with severe sICAS.

Understanding external carotid artery collateralisation after cerebral revascularisation in moyamoya disease: insights from quantitative analysis

BackgroundThis study aims to quantitatively evaluate collateralisation angiogenesis ratio (CAR) of external carotid artery and intracranial arterial residual volumes (ARV) postcerebral revascularisation in moyamoya disease (MMD) and elucidate the factors...

The Vecta 46 intermediate catheter for mechanical thrombectomy of distal medium vessel occlusions: A single-center experience.

With emerging evidence supporting the clinical efficacy and safety of mechanical thrombectomy (MT) for distal medium vessel occlusions (DMVOs), MT devices specifically designed to navigate through smaller caliber and more delicate tortuous distal cerebrovasculature are required. This study describes our single-center experience using the AXS Vecta 46 intermediate catheter for first-line thromboaspiration of DMVOs. We identified all patients who underwent MT using the Vecta 46 for first-line thromboaspiration for primary or secondary DMVOs. We collected baseline clinical data, angiographic and clinical outcomes, as well as procedural complications. The primary outcome in question was the rate of successful recanalization, which was defined as a modified Thrombolysis in Cerebral Infarction score of ≥2b. We identified 43 patients who underwent MT using the Vecta 46 catheter for thromboaspiration of 54 DMVOs. Intervened vessels included the M2 (23/54), M3 (19/54), and M4 (6/54) branches of the middle cerebral artery, A2 (1/54), A3 (1/54), and A4 (1/54) branches of the anterior cerebral artery, and P1 (1/54), P2 (1/54), and P4 (1/54) branches of the posterior cerebral artery. The median number of passes for primary DMVOs was 2 (IQR: 1-3) and 1 (IQR: 1-1.25) for secondary DMVOs. The rate of successful recanalization was 100% (18/18) for primary DMVOs and 80.6% (29/36) for secondary DMVOs. First-pass effect (FPE) was noted in 55.6% (30/54) of all primary and secondary DMVO cases. Improved short-term clinical outcomes were observed in both the primary (National Institute of Health Stroke Scale [NIHSS] shift: -5 [IQR: -14.25 to -0.25]) and secondary (NIHSS shift: -5 [IQR: -10 to -2]) DMVO groups. A total of six patients died during their hospitalization, though none were deemed procedural-related. Our study demonstrates the safety and efficacy of the Vecta 46 intermediate catheter for thromboaspiration of both primary and secondary DMVOs, achieving high rates of successful recanalization and FPE.

Anatomy of Inferior Temporal Arteries in Relation to Middle Cranial Fossa Structures: A Postmortem Computed Tomography Angiography Study

Abstract Objective The inferior temporal arteries (ITAs), branches of the posterior cerebral artery (PCA), are critical vascular structures encountered during subtemporal surgical approaches. Anatomical data based on multiphase postmortem computed tomography angiography (MPMCTA) are provided as a tool for preoperative surgical planning to lower the risk of ITA injury. Methods Adult (≥18 years) cases that underwent MPMCTA during 2015 to 2023 and whose cause of death did not involve the cerebral circulation were included in the study. Standardized measurements on four predefined coronal slices in relation to the posterior clinoid process (PCP) were established with references to projections in axial and sagittal planes. The main aim was to assess the presence, width, and course of anterior ITA (AITA), middle ITA (MITA), and posterior (PITA) particularly within the individual established quadrants of the middle cranial fossa. Results A total of 74 hemispheres were studied among 37 patients with the mean age of 52 ± 20.2 years. PITA was present in 98.7% of studied hemispheres, followed by MITA in 90.7% and AITA in 89.2%. The course of PITA was straight (65.8%) or oblique (34.3%), with significant difference in mean width (p = 0.050), branching angle (p &lt; 0.001), distance to tentorial hiatus (p &lt; 0.001), and superior petrosal sinus (p &lt; 0.001). A pattern of PITA loop was defined as a twisting of its course within the collateral sulcus. Significant relationship between the presence of AITA and MITA (p &lt; 0.001) along with the co-presence of AITA and PITA (p = 0.029) was found. Conclusion Knowledge of ITA characteristics and their relationship to surrounding anatomical structures is vital in subtemporal neurosurgical interventions. Preoperative inspection of the collateral sulcus and its relation to the surgical trajectory is critical to prevent PITA injury.