Search

Purpose: To investigate the differences in endovascular thrombectomy (EVT) outcomes of patients treated for acute ischaemic stroke (AIS) during business versus off-business hours. Methods: A single-centre retrospective cohort study of patients with AIS treated with EVT from February 1, 2015, to May 31, 2021, was performed at a comprehensive stroke centre (CSC). Patients were divided into business (Monday to Friday, 8 AM-5 PM) versus off-business hours groups. The primary outcome was functional neurological disability, scored using the modified Rankin Scale (mRS) at 90 days. Secondary outcomes included the rate of successful reperfusion and procedural workflow time delays. Differences in proportions were assessed using Fisher's exact and Chi-Square tests as appropriate. For continuous variables, differences in medians between groups were assessed using Mann-Whitney U tests. Results: A total of 676 patients were included, with 399 patients (59%) comprising the off-business-hour group. No significant differences were seen in age, sex, ASPECTS score, or NIHSS at arrival. Off-business hours strokes had a longer delay between CSC arrival to groin puncture (minutes: 81 vs 44, P <.0001) and between imaging to groin puncture (minutes: 67 vs 32, P <.0001) compared to the business hours strokes. There were no differences in the rate of successful reperfusion (mTICI ≥2b) between groups (82% vs 83%, P =.61). At 90 days, 65% of patients in both groups had an mRS ≤2 (P =.91). Conclusion: Despite workflow delays in initiating EVT during off-business hours, there were no differences in the rate of successful reperfusion or functional outcomes. [ABSTRACT FROM AUTHOR]

Endovascular treatment of complex vascular pathologies in the pediatric population is often performed by nonpediatric subspecialists with adaptation of equipment and techniques developed for adult patients. We aimed to report our center's experience with safety and outcomes of endovascular treatments for pediatric vascular pathologies. We performed a retrospective review of our endovascular database. All patients ≤18 years who underwent endovascular treatment between January 1, 2004 and December 1, 2022 were included. During the study time frame, 118 cerebral angiograms were performed for interventional purposes in 55 patients. Of these patients, 8(14.5%) had intracranial aneurysms, 21(38.2%) had intracranial arteriovenous malformations, 6(10.9%) had tumors, 5(9.1%) had arterial occlusions (n = 3) or dissections (n = 2), 8(14.5%) had vein of Galen malformations, and 7(12.7%) had other cerebrovascular conditions. Of the total 118 procedures, access-site complications occurred in 2(1.7%), intraprocedural complications occurred in 3(2.5%), and transient neurological deficits were observed after 2(1.7%). Treatment-related mortality occurred in 1(1.8%) patient. Neurointervention in pediatric patients was safe and effective in our experience. [ABSTRACT FROM AUTHOR]

Endovascular treatment for isolated dural arteriovenous fistula (DAVF) in the middle cranial fossa (MCF) with pure cortical venous drainage poses challenges, including the absence of a safe access route for transvenous embolization (TVE) and the risk of ischemia to neuro feeding vessels and dangerous anastomosis at the sphenoid wing. Therefore, surgical treatment involving direct blockage of venous reflux via craniotomy is typically preferred. We describe the case of a 63-year-old woman presented with generalized seizures and was diagnosed with a Borden III left MCF-DAVF. Initial TVE was unsuccessful due to an occluded inferior petrosal sinus and a lack of connection between the cavernous sinus and the shunt point. After reducing the shunt flow with transarterial embolization, retrograde TVE through cortical drainage enabled successful treatment for the DAVF. We used a triple coaxial system (4-French guiding sheath, 3.2-French intermediate distal access catheter, and 1.5-French microcatheter) to retrogradely navigate a microcathter from the right jugular vein through the superior sagittal sinus, the vein of Trolard, and into the superficial middle cerebral vein, ultimately achieving shunt occlusion using several coils. This case demonstrates that TVE for MCF-DAVFs with pure cortical venous drainage is feasible when a safe anatomical route is established using appropriate strategies and instruments and provides a safe and effective treatment option for similar cases.

Peri-medullary arteriovenous fistula (PMAVF) is a rare spinal vascular malformation that manifests as progressive neurologic deficits or hemorrhage in the spinal canal. We report a case of high-flow PMAVF in a child, with a single feeder artery and a large venous pouch, which was successfully treated with transarterial endovascular intervention. A 2-year-old boy was referred with a progressive 2-year history of myelopathy. The MRI revealed a large venous pouch at the midthoracic spinal cord with segmental surrounding edema. A spinal angiogram confirmed high-flow PMAVF with a single feeder artery from the anterior radiculomedullary artery, draining into the peri-medullary vein. The patient underwent transarterial embolization at the distal feeder artery, resulting in gradual motor strength improvement. PMAVF is classified as type IV spinal vascular malformation, usually presenting as a large, high-flow fistula with multiple feeders, although there was only one in this case. PMAVFs are intradural and may cause severe neurologic deficits due to mass effect, venous congestion, or hemorrhage, hence requiring prompt treatment. Treatment options for PMAVF include microsurgery, endovascular intervention, or a combination of the 2. Endovascular intervention with coil or liquid embolic material is considered first-line treatment for IVc PMAVF, and effective in type IVb with good clinical outcome. PMAVF is a rare spinal vascular malformation commonly manifesting as severe neurologic deficits but has the potential of favorable outcomes with endovascular therapy. This case demonstrates a unique angioarchitecture of high-flow PMAVF with a single feeder artery and large venous pouch, treated successfully with endovascular therapy.

Brain arteriovenous malformations (AVM) present complex treatment decisions, particularly for low-grade AVM where surgical resection is often considered the standard. This case report emphasizes the importance of patient preferences and cultural considerations in selecting endovascular embolization over traditional surgical approaches for Spetzler-Martin Grade I AVM management, highlighting the evolving practice of patient-centered care in neurointervention. A 30-year-old male presented with recurrent seizures, characterized by a sudden onset of headache followed by speech arrest, without any preceding medical history of neurological deficits. Initial physical examination revealed no focal neurological deficits. Non-contrast computed tomography, magnetic resonance imaging, and magnetic resonance angiography suggested an AVM involving the cortical-subcortical regions of the left frontal lobe, measuring approximately 1.7 × 2.6 × 1.5 cm, fed by the left middle cerebral artery M3 segment, and draining into the superior sagittal sinus. Spetzler-Martin Grade I classification was confirmed via digital subtraction angiography. Given the patient's strong preference against invasive procedures, driven by personal and cultural beliefs, endovascular embolization was selected as the treatment strategy. Post-embolization, the patient showed marked symptomatic improvement with no evidence of residual AVM on follow-up imaging, and no postprocedure complications were reported. This case highlights the importance of considering patient preferences in AVM treatment planning, illustrating that endovascular embolization can be an effective and less invasive alternative to surgery in selected patients, reinforcing the need for personalized, patient-centered approaches in neurointerventional care.

Radial loops are infrequent; however, they are a major cause for failure of radial access for procedure. Interventionists should be familiar with bail-out techniques when a radial loop is encountered to avoid spasm/injury. We describe our experience with two cases with 360 degrees radial loop in which we used low-profile microcatheter system to successfully complete the procedure

Abstract Background Trans-radial (TRA) access has become increasingly prevalent in neurointervention. Nonetheless, mediastinal hematoma after TRA is an infrequent yet grave complication associated with a notably elevated mortality rate. While our review found no reported mediastinal hematoma cases managed conservatively within neuro-interventional literature, similar complications are documented in cardiac and vascular interventional radiology, indicating its potential occurrence across disciplines. Case Presentation Carotid computed tomography angiography (CTA) showed calcified plaques with stenosis (Left: Severe, Right: Moderate) in the bilateral internal carotid arteries (ICAs) of an 81-year-old male presented with paroxysmal weakness in the right upper limb. Dual antiplatelet therapy with aspirin and clopidogrel was administered. On day 7, DSA of the bilateral ICAs was performed via TRA. Post-DSA, the patient experienced transient loss of consciousness, chest tightness, and other symptoms without ECG or MRI abnormalities. Hemoglobin level decreased from 110 g/L to 92 g/L. Iodinated contrast-induced laryngeal edema was suspected, and the patient was treated with intravenous methylprednisolone. Neck CT indicated a possible mediastinal hemorrhage, which chest CTA confirmed. The patient’s treatment plan involved discontinuing antiplatelet medication as a precautionary measure against the potential occurrence of an ischemic stroke instead of the utilization of a covered stent graft and surgical intervention. Serial CTs revealed hematoma absorption. Discharge CT showed a reduced hematoma volume of 35 × 45 mm. Conclusions This case underscores the need for timely identification and precise manipulation of guidewires and guide-catheters through trans-radial access. The critical components of successful neuro-interventional techniques include timely examination, rapid identification, proper therapy, and diligent monitoring.

Neurosurgeons often use radiation to visualize blood vessels and implants intraoperatively. However, high exposure to radiation increases one's cancer risk. This study aims to investigate intraoperative ionizing radiation exposure awareness and associated morbidity among neurosurgeons. An anonymized 30-question survey about their intraoperative radiation exposure, protective measures, radiation knowledge, and any conditions that can arise from protracted radiation exposure was disseminated to 3344 American Association of Neurological Surgeons members. A total of 227 (6.8%) neurosurgeons completed the survey. Most neurosurgeons (61, 27%) performed 2–4 surgeries per week necessitating radiation (61, 27%), did not use a dosimeter (134, 59%), and wore a lead apron (89%) and a thyroid shield (75%). Only 7 (3%) of respondents could correctly identify the safety limit for occupational radiation. One hundred and thirty-four (59%) respondents correctly identified the relationship between distance and radiation dose reduction. Two hundred and thirteen (94%) neurosurgeons reported concern about occupational radiation exposure. No significant association was found between occupational radiation exposure and the rate of cataracts, combined cancer, and skin cancer. Multivariate logistic regression adjusting for age and cancer history found that the likelihood of developing leukemia (P = 0.02) and nonmalignant thyroid nodular disease (P = 0.01) is positively associated with increased total occupational radiation exposure. There is a need for improved radiation safety awareness among neurosurgeons, especially in the context of rising usage of minimally invasive surgery. This can allow for a greater understanding of radiation-associated risks among neurosurgeons and guide the implementation of safer practices. [ABSTRACT FROM AUTHOR]

Radial loops are infrequent; however, they are a major cause for failure of radial access for procedure. Interventionists should be familiar with bail-out techniques when a radial loop is encountered to avoid spasm/injury. We describe our experience with two cases with 360 degrees radial loop in which we used low-profile microcatheter system to successfully complete the procedure [ABSTRACT FROM AUTHOR]

Purpose: Transradial access (TRA) for diagnostic and interventional neurointerventional procedures has recently gained traction over transfemoral access (TFA) in the neurointerventional community. This meta-analysis aims to assess and summarize the utility of TRA in cerebral angiography and neurointerventional procedures. Methods: A systematic literature review was performed utilizing Pubmed, Embase, and Scopus databases. Using PRISMA guidelines, records were extracted with the following search terms: transradial approach, transradial access, radial access, cerebral angiogram, cerebral angiography, neurointervention, and neuroendovascular. The primary outcomes assessed were case success rate, complication rate, and crossover rate from TRA to TFA. Secondary analysis was performed on procedure time, fluoroscopy time, fluoroscopy time per vessel (diagnostic procedures only), contrast dose, radial artery diameter, distal radial artery diameter, and patient preference for TRA over TFA. Results: Sixty-two full-text articles were analyzed for this meta-analysis, representing 12,927 diagnostic and interventional TRA access patients. Our analysis revealed a combined diagnostic and interventional case success rate of 95.9% and complication rate of 3.5%, with crossover to TFA occurring in 4.9% of cases. Conclusion: This meta-analysis demonstrates that TRA access for diagnostic angiography and neurointerventional procedures is a safe and effective approach, though determining a true complication rate is challenging as the definition of TRA complications has changed in various publications over time. [ABSTRACT FROM AUTHOR]

Key Clinical Message: Cerebral venous sinus thrombosis in itself is rarely encountered clinical entity and its association with immune thrombocytopenic purpura (ITP) makes it more unusual presentation. No any as such standard guidelines exist that guides the prompt evidence based management in such concurrent cases but neuroendovascular modality can play a pivotal role. [ABSTRACT FROM AUTHOR]

Background: Large core acute ischemic strokes have predominantly been excluded from endovascular therapy (EVT) studies due to perceived higher risks of hemorrhage and poorer functional outcomes. However, recent randomized controlled trials (RCTs) indicate that EVT for large vessel occlusion (LVO) strokes improves functional outcomes compared to medical management alone, despite higher hemorrhagic transformation rates, with no corresponding increase in symptomatic intracerebral hemorrhage (sICH) rates. The real-world outcomes of this intervention in Indian patients remain underexplored. Objectives: To evaluate the real-world outcomes of EVT for large core acute ischemic strokes with LVO in an Indian population. Methods: We conducted a single-center, retrospective observational study using a 7 years prospective database of EVT in anterior circulation stroke patients. Patients with Alberta Stroke Program Early Computed Tomography Score (ASPECTS) of 3–5 were included. Clinical and radiologic data were analyzed, with the primary endpoint being 90-day modified Rankin scale (mRS) scores. Safety outcomes included rates of sICH and mortality. Descriptive statistical analysis was done using Microsoft Excel. Results: The study included 25 patients who met the inclusion criteria. Mean age of patients was 52.9 ± 14.3 years, and there were 13 (52%) males. Median ASPECTS was 5 (interquartile range 4–5). Successful recanalization, classified by modified Thrombolysis in Cerebral Infarction score, was 92%. Good functional recovery, that is, 90-day mRS 0–3, was achieved in nine (36%) patients. Safety outcomes: sICH was seen in four (16%) and mortality was reported in nine (36%) patients. Conclusions: Our results reaffirm findings from RCTs, provide updated real-world evidence, and suggest that EVT is a viable option to be considered in selected patients with large core ischemic infarcts.

Background: Large core acute ischemic strokes have predominantly been excluded from endovascular therapy (EVT) studies due to perceived higher risks of hemorrhage and poorer functional outcomes. However, recent randomized controlled trials (RCTs) indicate that EVT for large vessel occlusion (LVO) strokes improves functional outcomes compared to medical management alone, despite higher hemorrhagic transformation rates, with no corresponding increase in symptomatic intracerebral hemorrhage (sICH) rates. The real-world outcomes of this intervention in Indian patients remain underexplored. Objectives: To evaluate the real-world outcomes of EVT for large core acute ischemic strokes with LVO in an Indian population. Methods: We conducted a single-center, retrospective observational study using a 7 years prospective database of EVT in anterior circulation stroke patients. Patients with Alberta Stroke Program Early Computed Tomography Score (ASPECTS) of 3-5 were included. Clinical and radiologic data were analyzed, with the primary endpoint being 90-day modified Rankin scale (mRS) scores. Safety outcomes included rates of sICH and mortality. Descriptive statistical analysis was done using Microsoft Excel. Results: The study included 25 patients who met the inclusion criteria. Mean age of patients was 52.9 ± 14.3 years, and there were 13 (52%) males. Median ASPECTS was 5 (interquartile range 4-5). Successful recanalization, classified by modified Thrombolysis in Cerebral Infarction score, was 92%. Good functional recovery, that is, 90-day mRS 0-3, was achieved in nine (36%) patients. Safety outcomes: sICH was seen in four (16%) and mortality was reported in nine (36%) patients. Conclusions: Our results reaffirm findings from RCTs, provide updated real-world evidence, and suggest that EVT is a viable option to be considered in selected patients with large core ischemic infarcts. [ABSTRACT FROM AUTHOR]

Background: Improved endovascular methods make it possible to treat complex ruptured aneurysms, but surgery is still needed in certain cases. We evaluated the effects on the clinical results of the changes in aneurysm treatment. Methods: The study cohort was 837 patients with spontaneous subarachnoid hemorrhage (SAH) and one or multiple aneurysms, admitted to Dept of Neurosurgery, Uppsala University Hospital from 2012 to 2021. Demography, location and treatment of aneurysms, neurologic condition at admission and discharge, mortality and last tier treatment of high intracranial pressure (ICP) was evaluated. Functional outcome was measured using the Extended Glasgow Outcome Scale (GOSE) Data concerning national incidences of stroke diseases was collected from open Swedish databases. Results: Endovascular methods were used in 666 cases (79.6%). In 111 (13.3%) with stents. Surgery was performed in 115 cases (13.7%) and 56 patients (6.7%) had no aneurysm treatment. The indications for surgery were a hematoma (51 cases, 44.3%), endovascular treatment not considered safe (47 cases, 40.9%), or had been attempted without success (13 cases, 11.3%). Treatment with stent devices increased, and with surgery decreased over time. There was a trend in decrease in hemicraniectomias over time. Both the patient group admitted awake (n = 681) and unconscious (n = 156) improved significantly in consciousness between admission and discharge. Favorable outcome (GOSE 5–8) was seen in 69% for patients admitted in Hunt & Hess I-II and 25% for Hunt & Hess III-V. Mortality at one year was 10.9% and 42.7% for those admitted awake and unconscious, respectively.The number of cases decreased during the study period, which was in line with Swedish national data. Conclusions: The incidence of patients with SAH gradually decreased in our material, in line with national data. The treatment policy in our unit has been shifting to more use of endovascular methods. During the study period the use of hemicraniectomies decreased. [ABSTRACT FROM AUTHOR]

Femoral access (TFA) for neuroendovascular procedures may present a challenge in very high body mass index (BMI) individuals. Whether radial access (TRA) confers a comparative benefit in this specific population has not been studied. We retrospectively identified all patients undergoing neuroendovascular procedures at our center between 2017 and 2021 with BMI ≥35 kg/m2. A total of 335 patients met our inclusion criteria, with 224 undergoing femoral access and 111 undergoing radial access. Electronic medical records were reviewed for baseline clinical and angiographic characteristics and procedural outcomes. The primary outcome of any bleeding complication occurred in 7% of the femoral group and 2% of the radial group (odds ratio 4.2, 95% confidence interval 1.0–18.6, P = 0.0421). Radial access was also associated with significantly shorter mean procedure times (median 43 minutes for radial, median 58 minutes for femoral, P = 0.0009) and mean fluoroscopy exposure times (median 15 minutes for radial, median 20 minutes for femoral, P = 0.0003). There were no significant differences in nonaccess site complications, procedural failure, length of stay, or deaths during hospitalization. When compared to TRA, TFA was associated with a significantly greater rate of bleeding complications in very high BMI patients undergoing neuroendovascular procedures. Procedure time and fluoroscopy time were both significantly longer when using TFA compared to TRA in this patient population. [ABSTRACT FROM AUTHOR]

Background: There are little available data regarding the influence of intravenous thrombolysis (IVT) on the efficacy of different first line endovascular treatment (EVT) techniques. Methods: We used the dataset of the SWIFT-DIRECT trial which randomized 408 patients to IVT + EVT or EVT alone at 48 international sites. The protocol required the use of a stent retriever (SR), but concomitant use of a balloon guide catheter (BGC) and/or distal aspiration (DA) catheter was left to the discretion of the operators. Four first line techniques were applied in the study population: SR, SR + BGC, SR + DA, SR + DA + BGC. To assess whether the effect of allocation to IVT + EVT versus EVT alone was modified by the first line technique, interaction models were fitted for predefined outcomes. The primary outcome was first pass mTICI 2c‑3 reperfusion (FPR). Results: This study included 385 patients of whom 172 were treated with SR + DA, 121 with SR + DA + BGC, 57 with SR + BGC and 35 with SR. There was no evidence that the effect of IVT + EVT versus EVT alone would be modified by the choice of first line technique; however, allocation to IVT + EVT increased the odds of FPR by a factor of 1.68 (95% confidence interval, CI 1.11–2.54). Conclusion: This post hoc analysis does not suggest treatment effect heterogeneity of IVT + EVT vs EVT alone in different stent retriever techniques but provides evidence for increased FPR if bridging IVT is administered before stent retriever thrombectomy. [ABSTRACT FROM AUTHOR]

Background Because of the variability in patient responses to clopidogrel and to reduce the risk of thromboembolic complications, adjusting the antiplatelet regimen based on platelet function testing has become a widespread practice in neurointervention. We aimed to explore current patterns related to this practice. Methods We conducted a survey targeting neurointerventionalists, comprising multiple‐choice questions and opportunities for free‐text responses when necessary. The survey was distributed via a professional society distribution list (the Society of Vascular and Interventional Neurology) and 2 consortium emailing lists (WovenEndoBridge and Neurointerventional Research Consortia). The data obtained from the responses were analyzed using descriptive statistics. Results A total of 133 neurointerventionalists, representing 79 institutions within 27 countries, responded to the survey. A total of 62% of respondents tested for clopidogrel resistance before any neurovascular stent placements. A total of 80% used VerifyNow point‐of‐care P2Y12 assay; other assays included multiplate analyzer, platelet function analyzer, and CYP2C19 genotype assay. Respondents reported 25 different therapeutic thresholds, with the P2Y12 reaction unit range between 60 and 180 most commonly used (16.4%). A total of 61% reported they would switch to ticagrelor in the case of persistent resistance. On the other hand, when patients are supratherapeutic, 48% did not make any changes, whereas 42% reduced clopidogrel dose. Finally, 93% opined that a well‐established protocol for management of clopidogrel resistance was needed. Conclusions Neurointerventional practice patterns around clopidogrel resistance remain heterogeneous. Our results underscore the need for evidence‐based guidance on the management of clopidogrel resistance in neurointervention.

Key Clinical Message Cerebral venous sinus thrombosis in itself is rarely encountered clinical entity and its association with immune thrombocytopenic purpura (ITP) makes it more unusual presentation. No any as such standard guidelines exist that guides the prompt evidence based management in such concurrent cases but neuroendovascular modality can play a pivotal role.

Abstract Background A carotid-cavernous fistula is an abnormal communication between the arteries and veins within the cavernous sinus. While conservative management may be prudent in low risk cases, many patients require intervention and endovascular embolization has evolved as the preferred method of treatment. Embolization can be performed via either the transarterial or transvenous approach. One major challenge of the transvenous approach is the complex and variable compartmentation of the cavernous sinus, which often requires the use of low profile microcatheters to navigate and reach the fistulous point. Fibered coils are also preferred when performing transvenous embolization of carotid-cavernous fistula, as they are of higher thrombogenicity and allow for faster occlusion of the fistula. However, most low profile (0.017-inch) microcatheters are not able to deploy fibered coils based on the manufacturer’s instructions. Case presentation We present two successful cases of off-label use of Medtronic Concerto fibered coils via a 0.017-inch microcatheter during transvenous embolization of carotid-cavernous fistula in a 60-year-old and an 80-year-old Chinese female, respectively. Conclusion Our case series highlight the possibility of deploying large diameter (up to 10 mm) Concerto fibered coils through a low profile (0.017-inch) microcatheter in an off-label manner for transvenous embolization of indirect carotid-cavernous fistula.

Complex intracranial aneurysms pose significant challenges in the realm of neurointervention, necessitating meticulous planning and execution. This article highlights the crucial roles played by anesthetists in these procedures, including patient assessment, anesthesia planning, and continuous monitoring and maintaining hemodynamic stability, which are pivotal in optimizing patient safety. Understanding these complex procedures and their complications will aid the anesthetist in delivering optimal care and in foreseeing and managing the potential associated complications. The anesthetist's responsibility extends beyond the procedure itself to postprocedure care, ensuring a smooth transition to the recovery phase. Successful periprocedural anesthetic management in flow diverter interventions for complex intracranial aneurysms hinges on carefully orchestrating these elements. Moreover, effective communication and collaboration with the interventional neuroradiologist and the procedural team are emphasized, as they contribute significantly to procedural success. This article underscores the essential requirement for a multidisciplinary team approach when managing patients undergoing neurointerventions. In this collaborative framework, the expertise of the anesthetist harmoniously complements the skills and knowledge of other team members, contributing to the overall success and safety of these procedures. By providing a high level of care throughout the periprocedural period, anesthetists play a pivotal role in enhancing patient outcomes and minimizing the risks associated with these intricate procedures. In conclusion, the periprocedural anesthetic management of neurointervention using flow diverters for complex intracranial aneurysms is a multifaceted process that requires expertise, communication, and collaboration.

Yu Zhou,1– 3,&ast; Yong Ma,2– 4,&ast; Dongliang Qian,2,3,&ast; Zhou Zhou,5,6,&ast; Bin Li,2,3,&ast; Erqing Chai1– 3 1First Clinical Medical College, Lanzhou University, Lanzhou, People’s Republic of China; 2Cerebrovascular Disease Center, Gansu Provincial Hospital, Lanzhou, People’s Republic of China; 3Key Laboratory of Cerebrovascular Diseases, Lanzhou, People’s Republic of China; 4Clinical Medicine College, Ningxia Medical University, Yinchuan, People’s Republic of China; 5First Teaching Hospital of Tianjin University of Traditional Chinese Medicine, Tianjin, People’s Republic of China; 6National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion, Tianjin, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Erqing Chai, First Clinical Medical College, Lanzhou University, No. 204, Donggang West Road, Chengguan District, Lanzhou City, 730000, People’s Republic of China, Tel +86 13893439044, Email ldyy_chaieq@lzu.edu.cnPurpose: To explore the predictive value of atherogenic index of plasma(AIP) for carotid in-stent restenosis(ISR).Methods: Patients who underwent carotid artery stenting (CAS) in hospital from January 2016 to January 2021 were retrospectively enrolled. They were randomly divided into training and validation sets. Based on the results of carotid digital subtraction angiography (DSA) during the follow-up period, the patients were divided into ISR group and non-ISR group. The differences of AIP and lipid levels between the two groups were compared. The independent risk factors of ISR and the predictive value of AIP for ISR were analyzed. A nomogram was developed based on the independent risk factors, and the receiver operating characteristic (ROC) curve, the calibration curve and the decision curve analysis were conducted to assess the predictive ability and clinical practicability of the nomogram in both the training set and validation sets.Results: A total of 361 patients were enrolled, including 98 in the ISR group and 263 in the non-ISR group. In the training set, AIP was significantly higher in the ISR group than in the non-ISR group (P < 0.05) and was independently associated with ISR (OR= 10.912, 95% CI: 2.520– 47.248). When AIP was 0.10, it had the highest predictive value for ISR, with a sensitivity of 72. 1% and a specificity of 75.0%. Additionally, hypertension, residual stenosis, symptomatic stenosis and Hcy were also independent risk factors for ISR. The nomogram showed good discrimination performance and clinical practicability in both the training set (AUC = 0.827) and the validation set (AUC = 0.880).Conclusion: AIP was an independent risk factor for ISR and was closely related to ISR. The nomogram developed by AIP and other variables had good predictive ability and clinical practicability for ISR.Keywords: atherogenic index of plasma, carotid stenosis, carotid in-stent restenosis, neurointervention, nomogram

Background: A carotid-cavernous fistula is an abnormal communication between the arteries and veins within the cavernous sinus. While conservative management may be prudent in low risk cases, many patients require intervention and endovascular embolization has evolved as the preferred method of treatment. Embolization can be performed via either the transarterial or transvenous approach. One major challenge of the transvenous approach is the complex and variable compartmentation of the cavernous sinus, which often requires the use of low profile microcatheters to navigate and reach the fistulous point. Fibered coils are also preferred when performing transvenous embolization of carotid-cavernous fistula, as they are of higher thrombogenicity and allow for faster occlusion of the fistula. However, most low profile (0.017-inch) microcatheters are not able to deploy fibered coils based on the manufacturer's instructions. Case presentation: We present two successful cases of off-label use of Medtronic Concerto fibered coils via a 0.017-inch microcatheter during transvenous embolization of carotid-cavernous fistula in a 60-year-old and an 80-year-old Chinese female, respectively. Conclusion: Our case series highlight the possibility of deploying large diameter (up to 10 mm) Concerto fibered coils through a low profile (0.017-inch) microcatheter in an off-label manner for transvenous embolization of indirect carotid-cavernous fistula. [ABSTRACT FROM AUTHOR]

Introduction: Current methods for angioplasty and stenting of the intracranial vasculature for neurointervention are limited. The Wingspan Stent System is Food and Drug Administration (FDA) approved with human device exemption for a limited patient group and despite numerous prospective registries and trials demonstrating reasonable safety, still carries warnings from the FDA for its use. Given these limitations, we present the technical nuances and outcomes of the off-label use of the Resolute Onyx drug-eluting stent (DES) for neurointerventional purposes. Methods: Retrospective chart review of all patients undergoing a neurointerventional procedure with the Resolute Onyx DES was done from January 2017–2021. The Resolute Onyx is a coronary balloon-mounted drug-eluting (zotarolimus) single wire laser cut stent. Technical details and procedural outcomes were collected. Results: In total 40 patients had attempted placement of the Resolute Onyx DES with procedural success in 95% of patients. The most common vessel stented was the basilar artery, 30% (12/40). The most common indication was intracranial atherosclerotic disease in 62.5% (25/40) patients, followed by acute stroke in 17.5% (7/40) of patients. The technical and procedural outcomes were excellent with only one technical complication (2.5%). Conclusions: This series describes the initial technical safety and utility of utilizing a new generation balloon-mounted drug-eluting stent for neurointerventional purposes. This stent offers the potential for improved navigability, delivery, and outcomes compared to current neurointerventional options and warrants further study. [ABSTRACT FROM AUTHOR]

Complex intracranial aneurysms pose significant challenges in the realm of neurointervention, necessitating meticulous planning and execution. This article highlights the crucial roles played by anesthetists in these procedures, including patient assessment, anesthesia planning, and continuous monitoring and maintaining hemodynamic stability, which are pivotal in optimizing patient safety. Understanding these complex procedures and their complications will aid the anesthetist in delivering optimal care and in foreseeing and managing the potential associated complications. The anesthetist’s responsibility extends beyond the procedure itself to postprocedure care, ensuring a smooth transition to the recovery phase. Successful periprocedural anesthetic management in flow diverter interventions for complex intracranial aneurysms hinges on carefully orchestrating these elements. Moreover, effective communication and collaboration with the interventional neuroradiologist and the procedural team are emphasized, as they contribute significantly to procedural success. This article underscores the essential requirement for a multidisciplinary team approach when managing patients undergoing neurointerventions. In this collaborative framework, the expertise of the anesthetist harmoniously complements the skills and knowledge of other team members, contributing to the overall success and safety of these procedures. By providing a high level of care throughout the periprocedural period, anesthetists play a pivotal role in enhancing patient outcomes and minimizing the risks associated with these intricate procedures. In conclusion, the periprocedural anesthetic management of neurointervention using flow diverters for complex intracranial aneurysms is a multifaceted process that requires expertise, communication, and collaboration. [ABSTRACT FROM AUTHOR]

Background Artificial intelligence platforms, like Viz.ai with large vessel occlusion detection, have been used for disease detection and interprovider communication. Whether this software expedites patient transfer and evaluation for treatment needs further exploration. Methods A single‐center retrospective registry was queried for patients with acute large vessel occlusion of the intracranial internal carotid, middle cerebral M1 or M2 segments, or basilar artery treated in a comprehensive stroke network (8 spokes, 1 hub) for 6 months pre‐ and post‐implementation of the Viz large vessel occlusion platform (excluding a 1‐month “washout” period). Robust regression was used to summarize time from initial hospital contact to arterial puncture (primary outcome) between periods, with prespecified subgroup analyses, which were assessed using interaction terms. Results Of the 132 patients (n = 58 preintervention), there were nonsignificantly fewer patients undergoing endovascular therapy in the postintervention period (86.2% preintervention versus 73.0% postintervention; P = 0.07). Among patients who underwent endovascular therapy (n = 50 preintervention, n = 54 postintervention), there was a nonsignificant reduction in time from first contact to arterial puncture (median 155 minute preintervention versus 116 minute postintervention; P = 0.10); however, this became significant in adjusted robust regression accounting for stroke severity, age, Alberta Stroke Program Early Computed Tomography Scale score, daytime versus nighttime and weekend versus weekday arrival, and use of perfusion imaging (β −20.9 [95% CI, −40.5 to −1.4)]. There was also a significant interaction observed for the association between spoke versus hub arrival and the Viz large vessel occlusion period, with shorter intervals observed for transferred patients (n = 32 preintervention with a median of 169 versus 142 minutes for n = 33 postintervention; Pinteraction

Abstract Supratentorial veins are divided into superficial and deep venous systems. Most superficial veins drain into the superior sagittal sinus, cavernous sinus, transverse sinus, and inferior sagittal sinuses. Most deep veins drain into the internal cerebral vein, and some drain into the basal vein of Rosenthal, which head toward the great cerebral vein of Galen. The functional anatomy of the supratentorial cerebral veins can be explained by dividing them into (1) veins on the lateral surface of the cerebral hemisphere, (2) the basal vein of Rosenthal system, and (3) the internal cerebral vein system. Many anastomotic channels exist between the superficial venous systems, veins at the base of the brain, and transcerebral veins. To understand and prevent adverse neurointerventional effects, in this study, we review the cerebral venous anatomy from the viewpoint of venous collaterals.

Abstract The infratentorial veins are densely packed in a smaller space compared to the supratentorial veins and have many variations, such as disconnections and anastomoses. Knowledge of the functional venous anatomy of the posterior fossa is becoming increasingly important in neurointerventional procedures. The basic brainstem veins are longitudinal and transverse veins. The venous drainage of the brainstem and cerebellum follows 3 paths: superior (Galenic), anterior (petrosal), and posterior (torcular). Knowledge of the basic venous anatomy of the brainstem and cerebellum is essential for understanding the routes and patterns of venous drainage under pathological conditions, particularly in arteriovenous shunts. This review describes posterior fossa venous development and the functional venous anatomy of the posterior fossa, mainly the veins of the brainstem, cerebellum, and the emissary veins.

Abstract Background Many studies have shown that coronary angiography (CAG) and percutaneous coronary intervention (PCI) via distal radial access (DRA) are safe and effective. Safety and efficacy of neuroangiography and neurointerventions via DRA are unknown. Purpose Search the literatures on neuroangiography and neurointerventions via DRA and conduct a systematic review and meta-analysis. Methods PubMed, Embase and Cochrane were searched from inception to November 10, 2022. After literature screening, data extraction and assessment of literature quality, random effects model was used for meta-analysis. Results A total of 236 literatures were retrieved, and 17 literatures including 1163 patients were finally included for meta-analysis.The pooled access success rate was 0.96 (95% confidence interval, 0.94–0.98), and the heterogeneity was obvious (I2 = 55.5%). The pooled access-related complications incidence rate was 0.03 (95% confidence interval, 0.02–0.05), and the heterogeneity was not obvious (I2 = 15.8%). Conclusion Neuroangiography and neurointerventions via DRA may be safe and effective. DRA is an alternative access for neuroangiography and neurointerventions.

At the time of this writing, the coronavirus disease 2019 pandemic continues to be a global threat, disrupting usual processes, and protocols for delivering health care around the globe. There have been significant regional and national differences in the scope and timing of these disruptions. Many hospitals were forced to temporarily halt elective neurointerventional procedures with the first wave of the pandemic in the spring of 2020, in order to prioritize allocation of resources for acutely ill patients and also to minimize coronavirus disease 2019 transmission risks to non-acute patients, their families, and health care workers. This temporary moratorium on elective neurointerventional procedures is generally credited with helping to "flatten the curve" and direct scarce resources to more acutely ill patients; however, there have been reports of some delaying seeking medical care when it was in fact urgent, and other reports of patients having elective treatment delayed with the result of morbidity and mortality. Many regions have resumed elective neurointerventional procedures, only to now watch coronavirus disease 2019 positivity rates again climbing as winter of 2020 approaches. A new wave is now forecast which may have larger volumes of hospitalized coronavirus disease 2019 patients than the earlier wave(s) and may also coincide with a wave of patients hospitalized with seasonal influenza. This paper discusses relevant and practical elements of cessation and safe resumption of nonemergent neurointerventional services in the setting of a pandemic.

Background: Many studies have shown that coronary angiography (CAG) and percutaneous coronary intervention (PCI) via distal radial access (DRA) are safe and effective. Safety and efficacy of neuroangiography and neurointerventions via DRA are unknown. Purpose: Search the literatures on neuroangiography and neurointerventions via DRA and conduct a systematic review and meta-analysis. Methods: PubMed, Embase and Cochrane were searched from inception to November 10, 2022. After literature screening, data extraction and assessment of literature quality, random effects model was used for meta-analysis. Results: A total of 236 literatures were retrieved, and 17 literatures including 1163 patients were finally included for meta-analysis.The pooled access success rate was 0.96 (95% confidence interval, 0.94–0.98), and the heterogeneity was obvious (I2 = 55.5%). The pooled access-related complications incidence rate was 0.03 (95% confidence interval, 0.02–0.05), and the heterogeneity was not obvious (I2 = 15.8%). Conclusion: Neuroangiography and neurointerventions via DRA may be safe and effective. DRA is an alternative access for neuroangiography and neurointerventions. [ABSTRACT FROM AUTHOR]

Background and purpose: Several studies in the literature have attempted to subjectively assess the degree of visualization of different neurovascular structures using different contrast agents and concentrations. Given the recent contrast shortages, we aim to objectively compare the radiopacity achieved with four angiographic contrast agents used in clinical practice. Methods: Isovue 370, Visipaque 320, Omnipaque 300, and Isovue 300 were each drawn up at 25%, 50%, 75%, and 100% concentrations and compared against normal saline and air syringes. CT scans were obtained, and regions of interest were analyzed for radiopacity using Hounsfield unit (HU) measurements. An aneurysm model with different contrast concentrations was also scanned and dimensions compared. Two‐tailed t‐tests and Cohen's d coefficients were applied to assess for differences in mean HU measurements. Results: Isovue 370 and Isovue 300 had the highest and lowest mean HU, respectively (p <.001). Visipaque 320 at 25% concentration had the lowest mean HU at −.76. Statistically similar agents (p <.05) were Visipaque 320 and Omnipaque 300 at a 100% concentration (p =.30), and Omnipaque 300 and Isovue 300 at a 25% concentration (p =.73). Aneurysm dimensions among Isovue 370, Visipaque 320, and Omnipaque 300 were all similar, whereas with Isovue 300, the dimensions were significantly smaller (p <.05). Conclusion: Isovue 370 provides the highest HU radiopacity and the most accurate aneurysm measurements. Angiographic measurements obtained with Isovue 300 may underestimate the actual aneurysmal dimensions. Visipaque 320 and Omnipaque 300 at 100% concentration have similar mean HUs and are beneficial for patients with chronic kidney or cardiac disease. [ABSTRACT FROM AUTHOR]

The Wada test is used to lateralize the dominant hemisphere in epilepsy patients prior to surgery. Either amobarbital, methohexital, or propofol is injected via a transfemoral catheter into a unilateral carotid artery, briefly suppressing the ipsilateral cerebral hemisphere to allow functional evaluation of the opposite side. Here, we highlight and propose a radial artery approach for the Wada test, allowing easier arterial access, better patient comfort, and ample procedural efficacy. [ABSTRACT FROM AUTHOR]

Objective: Simulation training has focused on education and practical training. However, the adoption rate of neurointerventional simulation training in Japan is unknown. Therefore, we sent a questionnaire survey form to consulting specialists from the Japanese Society for Neuroendovascular Therapy (JSNET) to clarify the actual simulation training situation and compare the differences between university hospitals and general hospitals in Japan. Methods: The questionnaire survey was conducted in 243 neurosurgical training facilities that had JSNET consulting specialists between May 31, 2021 and July 31, 2021. The questionnaire survey forms were distributed by Google Forms. Results: A total of 162 facilities responded to the survey (response rate: 66.7%; 35.2% from university hospitals and 64.8% from general hospitals). The adoption rate for simulation training was 53.7%, and it was significantly higher in the university hospitals than in the general hospitals (64.9% vs. 47.6%, p = 0.035). On the simulation effectiveness survey, more than 80% of respondents answered that the simulation training was a useful tool for upskill training. The open-ended question on interventional simulation training showed that there are limiting factors such as financial constraints. Additionally, respondents expressed a desire for a standard neurointerventional simulation training and education program. Conclusion: The adoption rate for simulation training was 53.7% in the training facilities of JSNET, and it was higher in the university hospitals than in the general hospitals. Most of the respondents answered that simulation training is an effective tool to improve neurointerventional skills. They also requested the establishment of simulation training programs and simulation tools. [ABSTRACT FROM AUTHOR]

Purpose: Specific decisions made by neurointerventionists are often lost behind the data of large-scale trials, and many of these studies have taken place before the development of new techniques and devices. This study compares the stent-retriever assisted vacuum-locked extraction (SAVE) technique with a direct aspiration first pass (ADAPT), as well as the use of a balloon guide catheter (BGC), in intracranial internal carotid artery (IC-ICA) occlusions. Methods: Observational and retrospective study from an Italian hospital, including patients who underwent thrombectomy for IC-ICA occlusion between 1 January 2019 and 31 March 2021. Results: Out of 91 IC-ICA occlusions, the ADAPT was the first choice in 20 (22%) and the SAVE in 71 (78%). A BGC was used in 32 (35%) cases, always in conjunction with the SAVE technique. The use of SAVE technique without BGC was associated with the least risk of distal embolization (DE) in the territory occluded (44% vs. 75% when ADAPT technique was used; p = 0.03) and achieved first pass effect (FPE) more frequently (51% vs. 25%, p = 0.09). When the SAVE technique was used, BGC (BGC-SAVE) compared to no BGC (NoBGC-SAVE) was associated with a tendency for less DE (31% vs. 44%, p = 0.3), more FPE (63% vs. 51%, p = 0.5), the same median number of passes (1, p = 0.8) and similar groin-to-recanalization times (36.5 vs. 35.5 min, p = 0.5), none of which reached statistical significance. Conclusion: Our findings support the use of SAVE technique for IC-ICA occlusions; the added benefit of BGC compared to long sheaths was not remarkable in this sample. [ABSTRACT FROM AUTHOR]

Background Unruptured cerebral aneurysms (UCAs) have a relatively low prevalence of ≈3%, but detection can prevent devastating consequences of subarachnoid hemorrhage. Here, we assess the performance of a machine learning algorithm to identify UCAs and determine whether routine use of the algorithm improves detection and patient care. Methods From a prospectively maintained multicenter registry across 8 certified stroke centers (1 comprehensive and 7 primary), we identified patients who underwent computed tomography angiography for evaluation of possible stroke from March 14, 2021, to November 31, 2021. A convolutional deep neural network (Viz ANEURYSM) trained to identify UCAs at least 4 mm in size analyzed the images, and ground truth was provided by a blinded expert neuroradiologist. The primary outcome was rate of clinical follow‐up for UCAs detected by the machine learning algorithm. Results Among 1191 computed tomography angiograms performed during the study period, 50 (4.2%) were flagged by the machine learning algorithm as possibly demonstrating a UCA, of which 31 cases were confirmed as true positive (positive predictive value, 62%). There were a total of 36 true aneurysms with 4 cases of multiple aneurysms. Overall, the most common locations included internal carotid artery (42%). Of these cases, 10 (27.8%) were not noted in the clinical radiology report or clinical notes, with a median size of 4.4 mm (interquartile range, 1.6 mm), and 24 (67%) were not referred for follow‐up, with median size of 4.4 mm (interquartile range, 4.2 mm). Of the 24 aneurysms not referred for follow‐up, 15 (62.5%) had been noted in the radiology report. A total of 33.3% (5/15) of the detected but not referred cases had a diameter >7 mm, with median PHASES score of 7. Conclusions UCAs of sizes and intradural locations that require attention and may warrant treatment are frequently missed in routine clinical care. A machine learning algorithm that flags studies and notifies clinicians may minimize missed care opportunities.

The Wada test is used to lateralize the dominant hemisphere in epilepsy patients prior to surgery. Either amobarbital, methohexital, or propofol is injected via a transfemoral catheter into a unilateral carotid artery, briefly suppressing the ipsilateral cerebral hemisphere to allow functional evaluation of the opposite side. Here, we highlight and propose a radial artery approach for the Wada test, allowing easier arterial access, better patient comfort, and ample procedural efficacy.

Purpose: The transradial approach (TRA) in neuroendovascular treatment is known to have a lower risk of complications than the transfemoral approach (TFA). However, little research has focused on assessments of efficacy and risk of complications in the treatment of intracranial aneurysms. This study aimed to compare the efficacy and complications of TRA and TFA in coil embolization of unruptured intracranial aneurysms (UIAs) at our institution. Methods: Consecutive patients who underwent endovascular surgery via TRA or TFA at a single institution from 1 April 2019, to 28 February 2022, were retrospectively analyzed. Patients were classified into TRA and TFA groups and assessed using propensity-adjusted analysis for outcomes including fluoroscopy time, volume embolization ratio (VER), and complications. Results: A total of 163 consecutive UIAs were treated with coil embolization during the 35-months study period. The incidence of minor access site complications (ASCs) was significantly higher with TFA (20%, 25/126) than with TRA (2.7%, 1/37; p = 0.01). Propensity-adjusted analysis (matched for age, sex, aneurysm volume, embolization technique, and sheath size) revealed that TRA was associated with a lower risk of minor ASCs (odds ratio, 0.085; 95% confidence interval 0.0094–0.78; p = 0.029). However, TRA did not differ significantly from TFA with respect to fluoroscopy time, VER, major ASCs, and non-ASCs. Conclusions: Coil embolization for UIAs via TRA can reduce risk of minor ASCs without increasing the risk of non-ASCs compared with conventional TFA, and can achieve comparable results in term of efficacy and fluoroscopy time. [ABSTRACT FROM AUTHOR]

In this review article, we aim to provide a summary of the discoveries and developments that were instrumental in the evolution of the Neurointerventional field. We begin with developments in the advent of Diagnostic Cerebral Angiography and progress to cerebral aneurysm treatment, embolization in AVMs and ischemic stroke treatment. In the process we discuss many persons who were key in the development and maturation of the field. A pivotal aspect to rapid growth in the field has been the multidisciplinary involvement of the different neuroscience specialties and therefore we close out our discussion with excitement about ongoing and future developments in the field with a focus on treatments in the non-cerebrovascular disease realm. [ABSTRACT FROM AUTHOR]

Transfemoral access for neurointerventions has been a time-tested technique of entering the vascular network of the body and reaching the intended targets. However, it has its own share of shortcomings in the form of long admission times leading to increased costs, patient inconvenience and local (though infrequent) adverse affects. Transradial route has taken the interventional cardiology domain by storm and is staring now at other vascular domains especially neurointervention. It has shown better outcomes than the transfemoral route in many aspects. The current article discusses the vascular access perspectives with an exhaustive overview of the transradial route concerning its historical perspectives, its requirement in the current clinical scenario, the procedure per se including the adverse effects and whether it has the real world charm to displace the transfemoral route into the backseat. Transradial access in neurointervention is here to stay, however it would require training, certain modifications in the standard catheters that one currently uses for cerebral procedures and constant practice by the operator to cross the learning curve and attain a certain level of competence before he becomes comfortable with the technique.

Background and Objective: Over the last few years, there has been considerable interest in the neurointervention community to use transradial approach for diagnostic and therapeutic neurointerventions. Distal radial approach has been postulated as an effective technique with reduced risk of hand ischemia. Our objective was to assess the safety and feasibility of distal transradial access (DTRA) to perform diagnostic cerebral angiography. Materials and Methods: A retrospective evaluation of 25 patients who were taken for DTRA through the anatomical snuff box from December 2021 to March 2022 was done. Results: Twenty‑five diagnostic cerebral angiographies were attempted with DTRA in 25 patients (age, 23–70 years; mean age, 45.4 years; 10 (40%) females). The right distal radial artery mean diameter was 2.09 mm. The procedure was successful in 21 (84%) procedures. Failure was seen in four cases, with three being converted to the proximal transradial approach without any need for redraping and one was converted to the transfemoral approach. The reason for access conversion was a severe spasm in three cases and dissection in one case. Selective catheterization of the cranial vessels through a distal transradial approach was achieved in 92 (96.8%) of 95 vessels. No significant access site complications were seen in the study cohort. Conclusion: DTRA is a promising approach for diagnostic cerebral angiography. Interventionists should get accustomed to this approach by overcoming the initial learning curve. [ABSTRACT FROM AUTHOR]

Background: To evaluate factors that influence the successful cannulation of intracranial vessels using a transradial approach. Methods: A total of 61 transradial diagnostic angiograms were evaluated in a tertiary care center from July 2020 to December 2021. We evaluated the learning curve and aortic arch vessel factors that may influence the cannulation of intracranial major vessels using a transradial approach. Results: Learning curve for the procedure was established after 21 cases. We were successful in cannulating the supra-aortic arteries except in 4 cases where we were unable to cannulate the left VA (vertebral artery). Significant positive correlation was seen between time to Sim (Simmons curve) formation and aortic arch diameter (p =.002). Significant positive correlation was also seen between left VA take-off angle and time to cannulate left VA (p =.001) and negative correlation was noted between left CCA (common carotid artery) take-off angle and time to cannulate left CCA (p =.001). Conclusion: Transradial approach is a feasible and safe approach for performing cerebral angiography. Multiple factors can influence the procedure time and successful cannulation of intracranial vessels. With the availability of radial specific hardware in the future, procedural success and time taken to complete the procedure may improve. [ABSTRACT FROM AUTHOR]

Purpose: The off-label use of flow diverting stents (FDS) for treating cerebral aneurysms in small distal vessels is increasing in clinical practice with encouraging results; however, data directly addressing the parent vessel size are still scarce. Our aim was to evaluate the safety and efficacy of FDS placement in anterior and posterior circulation aneurysms with parent arteries ≤ 2 mm in a real-world representative setting. Methods: We retrospectively reviewed patients treated with FDS at the three participating university hospitals between 2009 and 2021. The inclusion criteria were the placement of at least one FDS in a parent vessel with a maximum diameter of 2 mm or less. The primary clinical safety endpoint was the absence of death, major or minor symptomatic stroke, transient ischemic attack and procedure-related intracranial hemorrhage. Clinical outcome was assessed using the modified Rankin Scale (mRS) score at the follow-up visit at 1 year. The primary efficacy endpoint was defined as complete and near-complete occlusion at the 1‑year follow-up. Results: We identified 55 patients harboring 56 aneurysms. The primary clinical safety endpoint was obtained in 93% of cases. The hemorrhagic and thromboembolic complication rates were 4% and 9%, respectively. No patient died or had a relevant discrepancy (> 1 point) at the pre-mRS and post-mRS. The primary efficacy endpoint was reached in 80% of cases. Conclusion: The use of FDS in vessels < 2 mm is technically feasible with good aneurysm occlusion rates and an acceptable safety profile. Nevertheless, it is essential to be aware of the of the main complications associated when operating in small diameter vessels. [ABSTRACT FROM AUTHOR]

Background Transradial access (TRA) has proven advantages in interventional cardiology and neurointervention. There is limited literature detailing radial artery occlusion (RAO) recanalization, and generally, RAO necessitates alternate access. The purpose of this study was to evaluate the safety and feasibility of TRA in patients with RAO, allowing successful completion of the intended neurointervention procedure. Methods and Results Prospectively maintained databases at 2 Australian high‐volume neurointervention centers between January 2019 and February 2022 were reviewed. All consecutive patients with RAO who underwent attempted TRA for diagnostic neuroangiography or neurointervention procedures were included. Sixty‐one attempts at TRA through RAO for neurointervention procedures were performed in 42 patients. The mean age was 54.9 years, and 65.6% were women. Fifty‐three cases (86%) successfully completed the intended neurointervention procedure following RAO recanalization: 33 cases of diagnostic cerebral angiography, 9 cases of cerebral vasospasms, 6 cases of aneurysm repairs, 3 cases of endovascular thrombectomies, 1 case of carotid artery stenting/angioplasty, and 1 case of intracranial dural arteriovenous fistula embolization. Six cases (9.8%) required conversion to alternate access to complete the procedure because of failed TRA or anatomical challenges to select the target vessel. Two cases (3.2%) experienced transient minor radial artery extravasation without clinical sequelae. No major complications were encountered. Conclusions TRA in patients with RAO for neurointervention procedures is both safe and feasible, with no significant additional equipment or cost. RAO is not a contraindication to radial artery access in neurointervention.