Rinaldo, Lorenzo

BACKGROUND AND OBJECTIVES: Ventriculoperitoneal shunt (VPS) placement is a common treatment for idiopathic normal pressure hydrocephalus (iNPH), but patients may require VPS revision. This study aims to evaluate the effectiveness of a standardized VPS placement protocol by comparing indications and rates of shunt revision compared with a historical institutional cohort. METHODS: All patients treated with VPS for “suspected” iNPH at a tertiary care center between January 2000 and January 2023 were retrospectively reviewed and divided into temporally distinct historical (before 2017) and standardized (after 2017) cohorts. Cumulative incidence and timing of VPS revision were compared using competing risks analyses. RESULTS: A total of 561 patients (median age 75.0 years) were identified with 324 (57.8%) in the historical and 237 (42.2%) in the standardized cohorts. Significant variations in surgical technique and shunt hardware were noted between the cohorts. With a median follow-up of 11.4 months for historical and 12.4 months for standardized cohort, shunt revisions occurred in 19.4% and 8.4% of patients in the historical and standardized cohorts, respectively ( P < .001). Revision indications also varied significantly with lower rates of overdrainage ( P < .001), infection ( P < .001), and proximal malfunction ( P = .042) but higher rate of distal malfunction ( P = .03) in the standardized cohort. Notably, no infections were noted in the standardized cohort. CONCLUSION: Risk of shunt revision among iNPH patients may be associated with modifiable factors related to surgical technique and shunt hardware selection. Importantly, no short-term complications such as hemorrhage, infection, or catheter malposition were observed with the standardized protocol. Development and refinement of standardized shunt protocols for iNPH patients should be commonplace to facilitate tracking, identification, and modification of modifiable technical risk factors.

Background Animal models are essential for evaluating endovascular device safety and efficacy. Rats offer advantages, such as genetic manipulability, lower cost, and shorter healing and breeding cycles, compared to large animals. These features support studying aneurysm healing mechanisms and enable high-throughput testing. We developed an optimal rat aneurysm model for device evaluation. Methods Saccular aneurysms were created at the origins of the left renal artery (LRA) with acetylsalicylic acid (ASA) (LRA/ASA group, n = 7); the right common iliac artery (RCIA) with ASA alone (RCIA/ASA group, n = 6) or ASA plus clopidogrel (CLP) (RCIA/ASA + CLP group, n = 7); and the left common iliac artery (LCIA) with ASA + CLP (LCIA/ASA + CLP group, n = 7). The origins of these arteries were surgically exposed. During temporary ligation of the vessel origin, the vessel was bisected and endoluminal elastase was incubated in the proximal stump for 10 min, followed by release of the proximal ligation and permanent ligation of the stump. Angiographical and histological analysis were performed 4 weeks post-procedure. Results Follow-up digital subtraction angiography revealed mean ± standard deviation aneurysm height/neck dimensions of 1.2 ± 0.4/1.2 ± 0.1, 2.9/3.1, 2.3 ± 0.6/1.9 ± 0.3, and 2.1 ± 0.6/2.0 ± 0.4 mm for the LRA/ASA, RCIA/ASA, RCIA/ASA + CLP, and LCIA/ASA + CLP groups, respectively. The survival rate was 29%, 17%, 71%, and 86% in the LRA/ASA, RCIA/ASA, RCIA/ASA + CLP, and LCIA/ASA + CLP groups, respectively. Histopathological analysis of these aneurysms confirmed the absence of the internal elastic lamina and revealed aneurysmal changes in the arterial wall, resembling the pathological findings observed in human aneurysm specimens. Conclusions Common iliac aneurysm models with ASA + CLP can be used to evaluate the safety and efficacy of endovascular devices.

Introduction Post‐market and multicenter studies report low complete occlusion rates (41‐49%) and higher retreatment rates (13%) following WEB deployment, compared to 3.8% with microsurgical clipping. While retreatment after WEB has been shown to be technically feasible, data on final angiographic outcomes remain limited. We performed a retrospective analysis of prospective databases from 14 cerebrovascular centers in the US to compare the safety and efficacy of retreatment versus continued observation for residual and recurrent aneurysms after initial WEB deployment. Materials/Methods Multinomial logistic regression was used to identify baseline characteristics of untreated and residual/recurrent aneurysms that may act as confounders, which then underwent propensity scored matching (PSM). Results Among 211 patients (125 observed, 86 retreated), retreatment was more common in initially ruptured aneurysms (p<0.001), which showed higher recurrence (p=0.036) and sac‐dominant residuals (p=0.004). These were primarily due to WEB compression on follow‐up (p=0.001), rather than incomplete occlusion with an appropriately sized device (p<0.001). Retreatment was associated with significantly higher rates of complete angiographic occlusion at last follow‐up compared to observation alone (p<0.001), a finding that remained consistent across subgroups defined by initial unruptured status, residual type, and recurrence patterns (all p<0.05). Clipping demonstrated higher, though statistically insignificant, rates of complete occlusion; flow diversion and stent‐assisted coil embolization yielded comparable complete occlusion rates at follow‐up. After propensity score matching, retreatment remained significantly associated with higher rates of complete angiographic occlusion (all p<0.05), with comparable outcomes observed between clipping and various endovascular approaches as above. Conclusion Retreatment improved complete occlusion rates; however, no aneurysmal hemorrhages occurred in either group. Further intervention may be unnecessary when the WEB device—whether compressed or intact (BOSS 0/1)—adequately protects the dome. In cases where WEB compression significantly exposes the aneurysm wall, stent‐assisted coiling or flow diversion can be performed safely and successfully, depending on vascular anatomy and surgeon preference. image image

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.

High-resolution imaging is critical for the diagnosis, treatment planning, and postoperative monitoring of cerebral aneurysms, which affect up to 5% of the population and pose a significant risk of rupture and subarachnoid hemorrhage. Surgical clipping remains a definitive treatment option, but metallic clips can introduce substantial imaging artifacts, complicating posttreatment assessment. This review synthesizes current knowledge on the impact of aneurysm clip materials and designs on artifact generation and explores strategies for artifact mitigation. Conventional materials like titanium are favored for their biocompatibility and reduced ferromagnetism but still cause beam hardening, streak artifacts, and signal loss in CT and MRI scans. Emerging alternatives, including ceramics, composites, polymers, and bioresorbable clips, show promise in reducing artifacts while maintaining mechanical reliability. Innovations in clip design, such as fenestrated or low-profile models, further aid in minimizing imaging distortion. Advanced imaging methods, including dual-energy CT, iterative reconstruction algorithms, and metal artifact reduction software, demonstrate significant improvements in image quality but may introduce limitations such as increased processing demands or subtle anatomical distortions. Future directions emphasize the development of next-generation clip materials, robotic-assisted surgical approaches, and artificial intelligence-driven reconstruction techniques to further optimize visualization and patient safety. Continued research and multidisciplinary collaboration will be essential to translate these innovations into routine neurosurgical practice.

Purpose Aneurysmal rupture and subarachnoid hemorrhage (SAH) have an exceptionally high mortality and morbidity burden. The aim of this study was to develop interpretable machine learning models for predicting short-term poor outcomes defined by the National Inpatient Sample Subarachnoid Hemorrhage Outcome Measure (NIS-SOM). Methods The National Inpatient Sample (NIS) database was queried from 2008 to 2018 to identify patients diagnosed with SAH who had undergone endovascular coiling or clipping for intracranial aneurysm. Demographic, comorbidity, risk factor, and hospital characteristic variables were recorded. Variables were preprocessed, and the feature space was reduced to include the most important features. To predict poor outcomes, machine learning models were trained and cross-validated before being evaluated on a separate testing set. Shapley Additive exPlanations of the best performing model was used for general and local model interpretation. Results Among 18,149 admissions (mean age 55 ± 14 years, 68.8% women), 52.9% had a poor outcome. Test-set AUCs ranged 0.74–0.80; a multilayer perceptron performed best (AUC 0.80, precision 0.74, recall 0.82). SHAP ranked the ten most influential variables: age, neurological comorbidity, paralysis, Medicare insurance, smoking status, Elixhauser burden, fluid-electrolyte disorders, weight loss, arrhythmia, and heart failure. Conclusions The modeling predicted nationwide aSAH prognosis with decent accuracy and highlighted clinical, socioeconomic, and system-level drivers of determinants of poor short-term outcome. These results support the potential of explainable ML tools as complementary tools for early risk stratification, guiding resource allocation, and informing prospective multi-center validation and implementation studies.

Background There has been growing interest in transradial procedures over the past decade due to substantial reductions in access site complications as well as improved patient recovery. While several radial-specific neurovascular catheters have come to market, all catheters that are compatible with a 7Fr sheath have small inner diameters (IDs) (0.079″–0.082″), which can limit use of modern intermediate catheters. while larger-ID catheters cannot be used with a radial sheath resulting in complications related to radial artery spasm and entrapment. We report our results using a novel 7Fr-sheath-compatible radial guide catheter with an 0.087″ ID (Piraeus 7Fr 87 NeuGlide catheter) for neurovascular procedures. Methods This is a single center retrospective case series of patients undergoing transarterial transradial neuroendovascular procedures using the Piraeus 7Fr 87 NeuGlide catheter. The primary outcome was delivery of the catheter to the target vessel and successful completion of the procedure without the need to convert to femoral access or an alternative guide. Descriptive statistics are reported. Results Forty patients were included. The most common procedure was middle meningeal artery embolization followed by aneurysm embolization. And 97.5% of procedures were completed successfully without conversion to femoral access; 75% were completed without the need of an intermediate guide catheter. One procedure required conversion to femoral access. There were no access site or neurological complications. Conclusion The Piraeus 7Fr 87 NeuGlide catheter is both safe and effective for neurovascular procedures. The larger ID and 7Fr compatible outer diameter allows for the use of standard 5Fr and 6Fr intermediate/aspiration catheters.

Abstract Introduction Moyamoya is characterized by idiopathic, progressive, large intracranial arterial steno-occlusion, affecting the anterior circulation of the brain. Common presentations include strokes, seizures, and headaches, which have been associated with poor sleep quality and sleep disorders in the general population. However, to our knowledge, sleep quality has not been previously investigated in Moyamoya disease. The aim of this study was to characterize self-reported sleep quality, sleepiness, sleep disorder diagnoses in patients with Moyamoya syndrome, and to explore possible association between sleep disturbance and quality of life in these patients. Methods We analyzed consecutive patients with Moyamoya evaluated at our institution who completed the Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS). We also abstracted the Patient-Reported Outcomes Measurement Information System (PROMIS) to measure person-centered physical, mental and social wellbeing. Results We studied 23 patients with mean age 41.8 ± 12.1 years old having disease duration of 3 ± 4.4 years. 15 (65.2%) had ischemic strokes. Mean total PSQI score was 6.9 ± 2.9, and 17 (73.9%) had poor sleep quality (PSQI&gt;5). Mean sleep efficiency was reduced at 80 ± 17%. Although Median ESS was 6 (IQR 3.25 – 8), most patients (91.3%) reported at least mild daytime dysfunction (Component 7≥1). Mean PSQI component scores (0 – 3 severity, 3 is worse) were 1.29 ± 0.62 (subjective quality), 1.1 ± 0.73 (sleep latency), 1.04 ± 0.83 (sleep duration), 0.87 ± 1.01 (sleep efficiency), 1.22 ± 0.52 (sleep disturbances), 0.3 ± 0.88 (sleep medication), and 1.1 ± 0.52 (daytime dysfunction). The total PSQI score was positively correlated with PROMIS score (r=0.47, p=0.044). Only one patient was diagnosed with obstructive sleep apnea and three with chronic insomnia. Conclusion Poor sleep quality appears to be a frequent problem in patients with Moyamoya disease. Sleep disturbance severity was similar to previous findings in clinical stroke populations. The apparent mismatch between subjective sleep disturbance and sleep disorder diagnoses suggest that sleep disorders are likely underdiagnosed in Moyamoya patients. The relationship between PSQI and PROMIS scores suggests that sleep disturbance may significantly affect quality of life in these patients. Support (if any)