Oushy, Soliman H

BACKGROUND AND OBJECTIVES: Preventive treatment of unruptured intracranial aneurysms (UIAs) requires assessment of treatment risks vs expected benefit. Although established scores exist to estimate rupture and growth risk, currently, no externally validated tools exist to estimate the risks of microsurgical treatment of UIAs. Clinical prediction models based on machine learning enable generation of personalized risk estimates for each individual patient based on their specific patient and aneurysm characteristics. METHODS: Using data from 20 international centers from the prediction of adverse events after microsurgery for intracranial unruptured aneurysms study on patients treated microsurgically for UIAs, we developed and externally validated clinical prediction models for 3 outcomes measured at hospital discharge: poor neurological outcome (modified Rankin Score ≥3), new sensorimotor neurological deficits, and all-cause adverse events (Clavien-Dindo Grade ≥1). RESULTS: A total of 3705 patients were included. Data from 13 centers (2881, 78%) were used for model development. Fully trained models were evaluated on 824 patients (22%) from 7 additional centers. Average age was 56 ± 12 years, and 1049 (28%) were male. At discharge, poor neurological outcome was seen in 514 patients (14%). New sensorimotor deficits were observed in 534 patients (14%), and 894 patients (24%) experienced adverse events until discharge. At external validation, prediction of poor neurological outcome was achieved with good calibration and an area under the curve (AUC) = 0.70 (95% CI: 0.63-0.75). Similarly, new neurological deficits were predicted with good calibration and with an AUC = 0.69 (95% CI: 0.63-0.74). Prediction of all-cause adverse events only achieved an AUC = 0.59 (95% CI: 0.55-0.64) with fair calibration. The prediction model was integrated into a web application accessible at https://neurosurgery.shinyapps.io/PRAEMIUM/. CONCLUSION: The developed models for prediction of poor neurological outcome and new sensorimotor neurological deficits at discharge exhibit good calibration and fair discrimination based on a multinational external validation, indicating that the predicted probabilities correspond well to real-world risks and may thus be clinically useful in more objectively estimating the risk of microsurgical treatment.

OBJECTIVE Objective values on procedural risk are essential to facilitate informed consent and optimize clinical decision-making in patients with unruptured intracranial aneurysms (UIAs). While robust heuristics, such as the PHASES (population, hypertension, age, size of aneurysm, earlier subarachnoid hemorrhage, and site of aneurysm) score, are established for predicting rupture risk, contemporary and granular benchmarks for procedural safety remain scarce. The multinational Prediction of Adverse Events After Microsurgery for Intracranial Unruptured Aneurysms (PRAEMIUM) study aims to comprehensively characterize contemporary adverse event rates following microsurgical treatment at high-volume expert centers, stratified by aneurysm location, morphology, and complexity factors to better inform individual risk/benefit analyses. METHODS A cohort study among 20 participating expert centers from 9 countries was established. Patients treated microsurgically for UIAs were included. The authors describe the epidemiology of treated patients and UIAs and a comprehensive adverse event profile using 3 outcomes measured at hospital discharge: 1) poor neurological outcome (modified Rankin Scale score ≥ 3), 2) new sensorimotor neurological deficits, and 3) all-cause adverse events (Clavien-Dindo grade ≥ 1). Subgroup reports were given for aneurysm location, morphology, and complexity factors (prior aneurysm treatment, calcifications, complex angioanatomy involving critical branch vessels or perforators, and thrombosis). The authors purposely chose discharge as the time point to capture early postoperative risks and complications in patients with asymptomatic UIAs, for whom preserving neurological function is paramount. RESULTS The cohort included 3705 patients (mean age 56 [SD 12] years, 28% male). Overall, at discharge 13.9% of patients (95% CI 12.8%–15.0%) had poor neurological functional outcomes, 14.4% (95% CI 13.3%–15.5%) had new sensorimotor deficits, and 24.1% (95% CI 22.8%–25.5%) experienced all-cause adverse events. Poor neurological outcomes ranged from 8.5% (M1 aneurysms) to 37.4% (posterior circulation aneurysms), neurological deficits from 9.3% (distal anterior cerebral artery [ACA] aneurysms) to 34.2% (posterior circulation aneurysms), and all-cause adverse events from 21.2% (distal ACA aneurysms) to 31.3% (posterior circulation aneurysms). Dissecting and fusiform aneurysms showed notably high rates of poor neurological outcomes (22.0%–33.3%), new deficits (25.4%–26.7%), and adverse events (26.7%–37.0%). Complexity factors significantly influenced outcomes, with prior treatment (22.9%, 19.7%, and 30.1%), calcification (16.3%, 18.1%, and 30.5%), complex angioanatomy (13.1%, 15.9%, and 26.9%), and thrombosis (19.6%, 23.9%, and 39.6%) notably increasing the risks for poor neurological outcomes, deficits, and adverse events, respectively. CONCLUSIONS This large international cohort provides contemporary benchmarks for microsurgical treatment of UIAs, emphasizing variability in outcomes based on aneurysm location, morphology, and complexity. The presented granular and quotable adverse event rates support informed patient counseling and individualized risk/benefit assessments in comparable high-volume centers.

Introduction: Iatrogenic cervical artery dissection (CeAD) may result from various procedures such as procedural and diagnostic angiography. Due to the rarity of iatrogenic CeAD, existing literature on management and outcomes is limited. This observational cohort study investigates clinical approaches and long-term outcomes of iatrogenic CeAD after endovascular interventions. Methods: We conducted a retrospective chart review to analyze patients who underwent endovascular treatments at the Mayo Clinic from 1998 to 2021. We focused on patients with iatrogenic CeAD resulting from interventions. Pertinent patient factors were extracted. Descriptive statistics highlighted the relationship between treatments and long-term clinical outcomes. Results: Between 1998 and 2021, 21,191 patients underwent catheter cerebral angiography. Among them, 32 had iatrogenic CeAD (30 identified as white, 23 women, median age 59 [range 40.5–92.9]). Common comorbidities included hypertension (62.5%), smoking (56.3%), and hyperlipidemia (46.9%). Of the 32 patients, 9(28.1%) had dissection with diagnostic angiograms, 6(18.8%) endovascular thrombectomy, 15(46.9%) aneurysm treatment, and 2(6.3%) angioplasty with or without stenting. The location of dissections was dependent upon the intervention: 17(53.1%) had internal carotid artery dissection, 13(40.6%) vertebral artery dissection, and 2(6.3%) common carotid dissection. One patient was symptomatic with neck pain. All dissections were diagnosed by cerebral angiography during the same session as the initial intervention. Only 4(12.5%) were treated with hyperacute stenting. Following diagnosis, 30(93.7%) were placed on antithrombotic therapy, including aspirin alone (34.4%) or dual antiplatelet therapy with aspirin and clopidogrel (37.5%). The median duration of acute treatment was 3 months. The median duration of imaging follow up was 1022 days. Follow-up imaging showed an excellent radiological course, with complete or nearly complete dissection remodeling. Conclusions: Iatrogenic CeAD with endovascular interventions is rare and typically benign. Most cases are managed medically without significant clinical complications or long-term negative outcomes. Single or dual antiplatelet therapies remain preferred treatments, in line with current trends. Key factors influencing clinical decision-making include location, occlusion rate, pseudoaneurysm formation, intracranial extension, distal collateral circulation, and ischemia.

Background Iatrogenic cervical artery dissection (CeAD) results from various procedures including interventional angiographic procedures and diagnostic angiography. Iatrogenic CeAD is rare, resulting in limited literature on management and outcomes. This observational cohort study investigates approaches and outcomes of iatrogenic CeAD after endovascular interventions. Methods We conducted a retrospective review for patients who underwent endovascular intervention with resulting iatrogenic CeAD at Mayo Clinic, Rochester, MN, from 1998 to 2021. Pertinent patient factors were extracted and descriptive statistics generated. Results Between 1998 and 2021, 21,191 patients underwent catheter-based cerebral angiography. Thirty-two had iatrogenic CeADs (23 women; median age 59 [range 40.5–92.9]). Common comorbidities included hypertension (62.5%), smoking (56.3%), and hyperlipidemia (46.9%). Nine (28.1%) had dissection with diagnostic angiograms, 6 (18.8%) endovascular thrombectomy, 15 (46.9%) intracranial aneurysm treatment/coiling, and 2 (6.3%) intracranial angioplasty with/without stenting. All dissections were diagnosed by cerebral angiography during the same session as initial interventions. Four (12.5%) underwent hyperacute stenting. Thirty (93.7%) were placed on antithrombotic therapy with aspirin alone (34.4%) or dual-antiplatelet therapy with aspirin and clopidogrel (37.5%). Median duration of acute treatment was three months. Follow-up imaging showed excellent radiological course. Conclusions Iatrogenic CeAD with endovascular interventions is rare and typically benign. Most are managed medically without complications or long-term negative outcomes. Oral single or dual-antiplatelet therapies are preferred compared to previous studies which emphasize intravenous anticoagulation. The duration of acute therapy varied from three months to lifelong. Key factors influencing clinical decision-making may include occlusion rate, pseudoaneurysm formation, intracranial extension, distal collateral circulation, and resultant ischemia.

Cerebrospinal fluid (CSF)-venous fistulas necessitate a comprehensive understanding of spinal venous anatomy for successful embolization. 1 This video details the essential technical and anatomical nuances of CSF-venous fistula embolization at various spinal levels, including the cervical, thoracic, and lumbar spine. Precise microcatheter navigation, guided by a detailed understanding of spinal venous anatomy, is crucial for reaching the fistula site and successful treatment. Embolization typically focuses on the foraminal vein, paraspinal vein, and lateral epidural plexus, aiming to create a comprehensive liquid embolic plug. 2 As experience with this procedure grows, continued refinement of techniques and exploration of optimal access routes will further enhance success rates.

Neurostimulation is an increasingly common treatment option for medically intractable epilepsy. SANTE (Stimulation of the Anterior Nucleus of the Thalamus for Epilepsy) and Responsive Neurostimulation (RNS) System are landmark neurostimulation trials that utilized either duty cycle or a responsive stimulation paradigm. A seizure-free outcome is rarely observed with responsive and duty cycle neurostimulation devices. Chronic subthreshold cortical stimulation (CSCS) is a promising treatment for adult drug-resistant epilepsy involving eloquent cortex and has demonstrated safety and efficacy. Herein, the authors describe the surgical technique as well as details of stimulation programming involved in CSCS placement to facilitate the adoption of this promising treatment. The video can be found here: https://stream.cadmore.media/r10.3171/2024.4.FOCVID2422

Background Mechanical thrombectomy (MT) is a well-established treatment modality for large vessel occlusion (LVO) in adults, but there are limited data in the pediatric population. The rarity of the condition makes prospective trial design difficult, and therefore evaluation of MT devices and outcomes is sparse. In pediatric LVO cases, some newer devices may be appropriate for use in revascularization procedures. Furthermore, illustrative specific device-access combinations have rarely been presented in young patients under the age of 5 years. Methods This was a single institution experience in intracranial MT procedures for pediatric acute ischemic stroke (AIS). A given procedure was included if there was an attempt at MT between 2015 and 2023. Results Sixteen endovascular procedures were performed in 15 patients with AIS, with a mean age of 7.4 years; eight patients were <5 years of age. MT was attempted in 15/16 (93.7%) procedures, including 11 (73.3%) in the anterior circulation and four (26.7%) in the posterior circulation; one case recanalized after medical treatment. The most common MT techniques were combined aspiration with a stentriever (n=10, 66.7%) and aspiration alone (n=3, 20%). Traditional stentrievers (4–6 mm) were used in seven cases and low-profile stentrievers in four cases. Improved reperfusion was achieved in all low-profile stentriever cases. Reperfusion of modified Thrombolysis in Cerebral Infaction ≥2b was obtained in 73.3% of cases, including 72.7% of those in which a stentriever was used. Conclusions Low-profile thrombectomy devices may achieve similar revascularization results to other approaches in challenging clinical scenarios observed in younger children.

Background Infantile-type dural arteriovenous shunts (IDAVS) are rare and heterogeneous vascular lesions, complicating their classification and management. The current tripartite classification of pediatric dural arteriovenous shunts (DAVS) into dural sinus malformation, infantile-type, and adult-type, does not stand up to scrutiny, given the variable presentations of the latter two types in children. We estimate the prevalence of IDAVS and evaluate the long term outcomes after endovascular treatment (EVT). Methods A retrospective review of a pediatric cerebrovascular database between 2006 and 2023 was conducted. Clinical and radiographic data were analyzed to evaluate the presentation and long term outcomes of IDAVS. Results IDAVS were identified in 8 (0.5%) of 1463 patients, with mean age at diagnosis of 34.7 months; male infants comprised 62.5%. The most common clinical presentations included macrocephaly (37.5%), seizures (25%), and dilated scalp veins (25%). EVT was performed in 87.5% of cases, averaging 5.8 procedures per patient. Radiographic obliteration was observed in 28.6%. Good clinical outcomes (modified Rankin Scale score of ≤2) were achieved in 85.7%. Our findings showcased discrepancies and limitations in the current classification of pediatric DAVS, prompting a re-evaluation. Conclusion IDAVS accounted for a small proportion of pediatric cerebrovascular pathologies, with markedly heterogeneous presentations. Stepwise selective embolization was associated with favorable outcomes, and is recommended over an aggressive approach with the goal of complete angiographic obliteration. Our proposed revised classification system bifurcates pediatric DAVS into dural sinus malformations and all other DAVS that are manifest in children, thereby enhancing diagnostic clarity and therapeutic approaches.

BACKGROUND AND OBJECTIVES: Schwannomas originating from the lower cranial nerves (LCNS) are rare and pose a significant surgical challenge. Resection is the mainstay treatment; however, risk of treatment morbidity is considerable, and the available literature regarding differential treatment outcomes in this vulnerable population is sparse. METHODS: A single-institution cohort study and systematic literature review of LCNS were performed. RESULTS: Fifty-eight patients were included: 34 underwent surgical resection and 24 underwent stereotactic radiosurgery (SRS). The median age at diagnosis was 48 years (range 17-74). Presenting symptoms were dysphagia (63%), dysarthria/hypophonia (47%), imbalance (33%), and hearing loss/tinnitus (30%). Tumor size was associated with surgical resection, as compared with initial SRS (4.1 cm vs 1.5 cm, P = .0001). Gross total resection was obtained in 52%, with tumor remnants predominantly localized to the jugular foramen (62%). Post-treatment worsening of symptoms occurred in 68% of surgical and 29% of SRS patients ( P = .003). Postoperative symptoms were mostly commonly hypophonia/hoarseness (63%) and dysphagia (59%). Seven patients (29%) had new neurological issues after SRS treatment, but symptoms were overall milder. The median follow-up was 60 months (range 12-252); 98% demonstrated meaningful clinical improvement. Eighteen surgical patients (53%) underwent adjuvant radiation at a median of 5 months after resection (range 2-32). At follow-up, tumor control was 97% in the surgical cohort and 96% among SRS patients. CONCLUSION: Although LCNS resection is potentially morbid, most postoperative deficits are transient, and patients achieve excellent tumor control—particularly when paired with adjuvant SRS. For minimally symptomatic patients undergoing surgical intervention, we advise maximally safe resection with intracapsular dissection to preserve nerve integrity where possible. For residual or as a primary treatment modality, SRS is associated with low morbidity and high rates of long-term tumor control.

Endovascular recanalization is increasingly being utilized in symptomatic patients with chronically occluded carotid arteries. 1 In carefully selected patients, endovascular recanalization has shown to lower the risk of ischemic events when compared to medical management alone.1 However, successful endovascular revascularization is technically challenging and not without risk. 1 , 2 In this video, we demonstrate a case of a 64-year-old woman who presented with recurrent transient ischemic attacks. On imaging she was found to have a chronic total occlusion of the common carotid artery from the arch. After obtaining informed consent, the patient underwent a successful endovascular recanalization and stenting of a chronically occluded left common carotid artery with aid from an intravascular guided re-entry catheter. Post operatively the patient developed a neck hematoma which improved and she returned to her neurological baseline. She reported no further symptoms on her three month follow up.