Timing, type, and impact of thromboembolic events caused by flow diversion: a 10-year experience.

OBJECTIVE: Thromboembolic (TE) events are among the most feared complications after flow diversion (FD) and have been reported to occur even with adequate dual antiplatelet therapy. Herein, the authors characterize thrombotic and embolic events that developed after FD, focusing on the morbidity of each of these events and the predisposing factors associated with their development. METHODS: A retrospective analysis of aneurysms treated with FD at a single institution in the US between 2013 and 2023 was performed. The authors documented the emergence of intraprocedural and postoperative TE events. A survival analysis and a Cox regression model was conducted to identify predictors associated with these events. RESULTS: The authors included 651 procedures performed in 591 patients to treat 746 aneurysms. TE events occurred in 38 of the procedures performed (5.8%), causing permanent deficit in 20 patients and death in 4 patients. Eleven cases presented with acute stent thrombosis, 11 with large-vessel occlusion, and 9 with perforator strokes. At a median follow-up of 9.5 months, 73.0% of patients with an ischemic event had a modified Rankin Scale score ≤ 2. Three of the deaths were secondary to occlusion at the basilar trunk and vertebral artery. In patients with TE events in the anterior circulation, 7 of 11 patients with middle cerebral artery occlusion and 9 of 12 patients with internal carotid artery occlusion achieved independence. Time-to-event Cox regression analysis demonstrated that TE events were more frequent in patients exhibiting aspirin resistance (hazard ratio 2.66; 95% CI 1.10-6.70). CONCLUSIONS: TE events after FD result from multiple factors, including age, aneurysm characteristics, aneurysm location, antiplatelet resistance, and procedural factors. In our cohort, we found the highest morbidity for patients with TE events presenting with large-vessel occlusion at the middle cerebral artery, and vertebrobasilar system.

A Novel Scoring System Predicting Aneurysm Incomplete Occlusion after Flow Diversion: A 10-year experience.

BACKGROUND: Factors impacting the rate of aneurysm occlusion after FD have been well described in the literature. In this paper, we sought to evaluate those variables to develop and validate a scoring system predicting aneurysm incomplete occlusion after FD. METHODS: Retrospective review of patients with intracranial aneurysms treated with FD at a single institution between March 2013 and March 2023. Multivariable logistic regression model was developed using factors associated with aneurysm incomplete occlusion. The ABC scoring system consisted of: Age (< 60 years old: 0, 60-69 years: 1, 70-79: 2, and ≥80: 3), Branch coming out of the aneurysm dome/neck (yes: 2, no:0), and Cigarette smoking history (never-smoker:1, current or past smoker: 0). The scoring system performance was evaluated with receiver operating characteristic curve and calculating the area under the curve (AUC). RESULTS: A total of 449 patients with 563 aneurysms treated in 482 procedures were evaluated. Most cases were females (81.7%) with a median age of 59 years-old. At a median follow-up of 13.2 months, 84.0% of aneurysms were completely or near-complete occluded. The scoring system had an AUC of 0.71. A value ≥2, reached a sensitivity of 74.4%, specificity of 60.9%, an LR+ of 1.90, and proved to be reliable in predicting the risk of incomplete occlusion (OR=4.53; 95% confidence interval, 2.73-7.54; P < 0.001). CONCLUSION: The proposed ABC scoring system can be used to evaluate the risk of aneurysm incomplete occlusion after treatment with FD, identifying patients who would benefit from adjunctive coiling or alternate treatment modalities.

The Neurovascular Disease Management Course: A Medical Student Opportunity for Early Exposure and Technical Development in Vascular Neurosurgery.

BACKGROUND: As endovascular neurosurgery techniques continue to evolve, medical students in the United States have widely varying exposures to the field, particularly with respect to opportunities for hands-on experiences. Current medical school curricula could benefit from a novel and adaptive course on vascular neurosurgery to increase student exposure earlier in their training. METHODS: We launched a yearly hands-on vascular neurosurgery course for medical students and residents. The day-long course is a combination of lectures focused on neurovascular disease and management accompanied by hands-on sessions where students practiced fundamental microsurgery and angiography techniques using real microscopes and angiography simulators. We surveyed the students before and after each of the 2 courses. The survey following the second annual course included quiz questions the students had not previously seen. RESULTS: Over 2 courses, we had 149 attendees, 71.8% of which were first and second-year medical students representing fifteen institutions. The average survey completion rate was 41.4% for the 4 surveys across the 2 courses. Attendees' interest in pursuing a surgical specialty (t = 1.815, P = 0.039) along with their comfort with neuroanatomy (t = 8.780, P ≤ 0.001) and neurosurgical disease (t = 6.133, P ≤ 0.001) was significantly elevated after the completion of the second course. Responses to the post-survey showed a good grasp of the fundamentals with 68% of attendees answering 70% of the quiz questions correctly. CONCLUSIONS: An interactive course on vascular neurosurgery may be an effective vehicle to provide medical students with exposure to the field and the opportunity to learn the fundamentals.

Endovascular Treatment of Basilar Apex Aneurysms: An Updated Systematic Review and Meta-Analysis in the Era of Flow Diversion.

BACKGROUND: Endovascular options for the treatment of basilar apex aneurysms (BAAs) are heterogeneous, and evidence is limited to retrospective cohorts and case series. We seek to evaluate the efficacy and complications associated with various endovascular treatment methods of BAAs. METHODS: Systematic review of PubMed, Embase, and Web of Science adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Retrospective and prospective studies evaluating endovascular treatment of BAAs between January 2010 and July 2024 were included. Relevant information including occlusion rates, aneurysm recurrence, retreatment rates, and complications were subjected to meta-analysis. RESULTS: Fifteen studies with 1049 BAAs were included. The median aneurysm diameter was 8.5 mm (range, 4.6-19.75), with a median follow-up of 33.7 months (range, 6.0-117.6). Residual aneurysm filling occurred in 24% after primary coiling (95% CI = 0.16-0.32), 25% after single stent-assisted coiling (s-SAC; 95% CI = 0.04-0.46), 25% after Y-stents (95% CI = 0.12-0.37), and 23% after flow diverter stent (FDS; 95% CI = 0.11-0.35). Recurrence rates were high for primary coiling (27%, 95% CI = 0.18-0.36) and s-SAC (19%, 95% CI = 0.13-0.26), but significantly lower for Y-stents (9%, 95% CI = 0.03-0.15) and FDS (4%, 95% CI = -0.04-0.11). Retreatment rates were 19% for primary coiling (95% CI = 0.12-0.26), 17% for s-SAC (95% CI = 0.07-0.27), 5% for Y-stents (95% CI = -0.03-0.12), and 13% for FDS (95% CI = -0.01-0.27). Meta-regression indicated larger aneurysms had higher complication rates (P = 0.02). Thromboembolic events were most frequent with FDS and Y-stents(12%). CONCLUSIONS: Occlusion rates were similar across treatments, but recurrence rates were significantly lower after Y-stents and FDS compared to primary coiling, although they carried a higher number of thromboembolic complications.

Defining light transmission aggregometry cutoff values for clopidogrel and aspirin resistance in flow diversion treatment of intracranial aneurysms.

OBJECTIVE: Concern about thromboembolic events after flow diversion (FD) warrants dual antiplatelet therapy for 3 to 6 months. Platelet function tests are routinely performed prior to the procedure to detect clopidogrel responsiveness, as resistance is associated with CYP2C19 gene polymorphisms. This study aimed to identify optimal cutoff values in light transmission aggregometry (LTA) for clopidogrel and aspirin as predictive indicators of thromboembolic complications. METHODS: The authors conducted a retrospective analysis of aneurysms treated with FD between 2013 and 2023 at a single academic institution. Patients with LTA data for adenosine diphosphate (ADP) and arachidonic acid (ARA) were included, excluding those with aborted procedures. Receiver operating characteristic curves were plotted for ADP and ARA assays to determine optimal cutoff values. RESULTS: A total of 442 patients harboring 552 aneurysms treated in 485 procedures were selected for this analysis. Complete and near-complete aneurysm occlusion on the last radiological follow-up was achieved in 81.8% of aneurysms in a median last imaging follow-up of 13.9 months. A good functional outcome (modified Rankin Scale score ≤ 2) was achieved in 96.3% of patients on the last follow-up. Thromboembolic complications occurred in 4.9% of procedures, and intracranial hemorrhagic complications in 1.9%. For the ADP assay, a value ≥ 40% reached a sensitivity of 82.1% and a specificity of 42.9% with a positive likelihood ratio (LR) of 1.50. For the ARA assay, a value ≥ 13.5% reached a sensitivity of 82.1% and a specificity of 45.6% with a positive LR of 1.51. CONCLUSIONS: This study analyzed the largest FD-treated cohort in which optimal LTA platelet function thresholds for clopidogrel were evaluated and is the first to assess LTA values for aspirin. The authors found that values ≥ 40% for clopidogrel and ≥ 13.5% for aspirin were optimal for predicting thromboembolic complications after FD in treating aneurysms.

Thromboembolic Events in the Posterior Circulation After Flow Diversion-A Closer Look at Coverage of the Posterior Cerebral Artery.

BACKGROUND: Flow diversion for bifurcation aneurysms requires excluding one of the branches from the parent artery, raising concern for ischemic events. We evaluated thromboembolic events and their relationship with covering the origin of the posterior cerebral artery (PCA). METHODS: This retrospective analysis included patients with confirmed basilar and proximal PCA aneurysms treated with flow diversion between 2013 and 2023. Procedures were classified according to the coverage of the origin of the PCA. Thromboembolic events associated with the excluded PCA were evaluated. RESULTS: Of the total 28 aneurysms included, 7 were at the basilar tip, 16 in the basilar trunk, and 5 in the first segment of the PCA; 15 were treated by excluding one of the PCAs. Dual antiplatelet therapy included aspirin and ticagrelor (57.1%), aspirin and clopidogrel (35.7%), or aspirin and prasugrel (3.57%). Complete and near-complete aneurysm occlusion was achieved in 80.8% of the aneurysms treated at a median follow-up of 12.31 months. Thromboembolic complications occurred in 3 patients (2 with basilar perforator stroke and 1 with basilar in-stent thrombosis). However, the difference in these events was not statistically significant between patients with PCA coverage and those without (P = 0.46). Diminished flow and a lack of flow was seen in 8 and 7 of the covered vessels, respectively. A modified Rankin scale score of ≤2 was reported for 89.3% of patients at a median clinical follow-up of 5.5 months. CONCLUSIONS: The incidence of thromboembolic events is high in distal basilar and proximal PCA aneurysms; however, PCA coverage was not associated with their occurrence. There was no difference in postprocedural disability between patients whose aneurysms were treated by excluding one of the PCAs and those who were not.

Provider Experience With the Use of Ketamine for Refractory Status Epilepticus.

OBJECTIVE: Refractory status epilepticus (RSE) treated with anesthetic agents can be associated with complications including respiratory depression and hypotension. Ketamine is an emerging RSE treatment, but optimal dosing and timing are unknown. We studied provider attitudes and practices regarding the use of ketamine for RSE. METHODS: A literature review informed the creation of the survey, developed by professionals in epilepsy, pharmacy, and neurocritical care. The survey was distributed to members of the Critical Care EEG Monitoring and Research Consortium, Neurocritical Care Society, American Academy of Neurology Synapse community, American Epilepsy Society, and the Canadian League Against Epilepsy. Descriptive statistics were calculated. RESULTS: There were 109 respondents. First-line agents for RSE were midazolam (53%), propofol (42%), pentobarbital (2%), and ketamine (1%). Reasons for ketamine use included failure of midazolam/propofol to control seizures (81%) or hypotension on another anesthetic (35%). Perceived contraindications included hypertension (37%), elevated intracranial pressure (24%), and heart failure (18%). Perceived benefits included decreased use of vasopressors (53%) and more rapid RSE control when used adjunctively (49%). Routine ketamine users often treated more than 10 RSE cases per year, worked as intensivists or at academic institutions. Of the respondents, 59% found ketamine useful for RSE and 94% were interested in learning more about its use. CONCLUSIONS: Although most participants found ketamine helpful for RSE, it is mainly used as a second-line agent adjunctively with midazolam or propofol. Perceived ketamine benefits included decreased need for hemodynamic support and more rapid seizure control when used in conjunction with other anesthetics. Perceived contraindications centered on cardiac and intracranial pressure concerns.

Comparison of Thromboembolic Events Between Pipeline Embolization Device (PED) Shield and PED/PED Flex: A Propensity Score-Matched Analysis.

BACKGROUND AND OBJECTIVES: The pipeline embolization device (PED) Flex with Shield technology is a third-generation flow diverter used for intracranial aneurysm treatment designed to decrease thrombogenicity through a phosphorylcholine coating. Herein, we aim to compare the rate of thromboembolic events in PED with Shield technology and PED without it through propensity score matching. METHODS: We conducted a retrospective analysis of aneurysms treated with PED first-generation/PED Flex and PED with Shield between 2013 and 2023 at a single academic institution. Patients were matched through propensity score by controlling for confounding factors including age, smoking history, diabetes, previous subarachnoid hemorrhage, modified Rankin Scale pretreatment, location, aneurysm size, previous treatment, and clopidogrel or aspirin resistance. After matching, we evaluated for periprocedural and postoperative thromboembolic events. Data analysis was performed using Stata 14. RESULTS: A total of 543 patients with 707 aneurysms treated in 605 procedures were included in the analysis. From these, 156 aneurysms were treated with PED with Shield (22.07%) and 551 (77.93%) without Shield technology. Propensity score matching resulted in 84 matched pairs. The rate of thromboembolic events was 3.57% for PED Shield and 10.71% for PED first-generation/PED Flex ( P = .07), while retreatment rates were 2.38% for PED Shield and 8.32% for PED Flex ( P = .09). Complete occlusion at first ( P = .41) and last imaging follow-up ( P = .71), in-stent stenosis ( P = .95), hemorrhagic complications ( P = .31), and functional outcomes ( P = .66) were comparable for both groups. CONCLUSION: This is the first study in the literature performing a propensity scored-matched analysis comparing PED with PED with Shield technology. Our study suggests a trend toward lower thromboembolic events for PED Shield, even after controlling for aspirin and clopidogrel resistance, and a trend toward lower aneurysm retreatment rates with PED Shield, without reaching statistical significance.

Rescue therapy after thrombectomy for large vessel occlusion due to underlying atherosclerosis: review of literature.

In this review article, we summarized the current advances in rescue management for reperfusion therapy of acute ischemic stroke from large vessel occlusion due to underlying intracranial atherosclerotic stenosis (ICAS). It is estimated that 24-47% of patients with acute vertebrobasilar artery occlusion have underlying ICAS and superimposed in situ thrombosis. These patients have been found to have longer procedure times, lower recanalization rates, higher rates of reocclusion and lower rates of favorable outcomes than patients with embolic occlusion. Here, we discuss the most recent literature regarding the use of glycoprotein IIb/IIIa inhibitors, angioplasty alone, or angioplasty with stenting for rescue therapy in the setting of failed recanalization or instant/imminent reocclusion during thrombectomy. We also present a case of rescue therapy post intravenous tPA and thrombectomy with intra-arterial tirofiban and balloon angioplasty followed by oral dual antiplatelet therapy in a patient with dominant vertebral artery occlusion due to ICAS. Based on the available literature data, we conclude that glycoprotein IIb/IIIa is a reasonably safe and effective rescue therapy for patients who have had a failed thrombectomy or have residual severe intracranial stenosis. Balloon angioplasty and/or stenting may be helpful as a rescue treatment for patients who have had a failed thrombectomy or are at risk of reocclusion. The effectiveness of immediate stenting for residual stenosis after successful thrombectomy is still uncertain. Rescue therapy does not appear to increase the risk of sICH. Randomized controlled trials are warranted to prove the efficacy of rescue therapy.

Taking a Chance to Recover: Families Look Back on the Decision to Pursue Tracheostomy After Severe Acute Brain Injury.

BACKGROUND: Tracheostomy represents one important and value-laden treatment decision after severe acute brain injury (SABI). Whether to pursue this life-sustaining treatment typically hinges on intense conversations between family and clinicians. The aim of this study was, among a cohort of patient who had undergone tracheostomy after SABI, to explore the long-term reflections of patients and their families as they look back on this decision. METHODS: For this qualitative study, we reviewed the electronic medical records of patients with SABI who underwent tracheostomy. We included all patients who were admitted to our 30-bed neuro-intensive care unit with SABI and underwent tracheostomy between November 2017 and October 2019. Using purposive sampling, we invited survivors and family members to participate in telephone interviews greater than 3 months after SABI until thematic saturation was reached. Interviews were audiotaped, transcribed, and analyzed by using thematic analysis. RESULTS: Overall, 38 patients with SABI in the neuro-intensive care unit underwent tracheostomy. The mean age of patients was 49 (range 18-81), with 19 of 38 patients diagnosed with traumatic brain injury and 19 of 38 with stroke. We interviewed 20 family members of 18 of 38 patients at a mean of 16 (SD 9) months after hospitalization. The mean patient age among those with an interview was 50 (range 18-76); the mean modified Rankin Scale score (mRS) was 4.7 (SD 0.8) at hospital discharge. At the time of the interview, ten patients lived at home and two in a skilled nursing facility and had a mean mRS of 2.6 (SD 0.9), and six had died. As families reflected on the decision to proceed with a tracheostomy, two themes emerged. First, families did not remember tracheostomy as a choice because the uncertain chance of recovery rendered the certain alternative of death unacceptable or because they valued survival above all and therefore could not perceive an alternative to life-sustaining treatment. Second, families identified a fundamental need to receive supportive, consistent communication centering around compassion, clarity, and hope. When this need was met, families were able to reflect on the tracheostomy decision with peace, regardless of their loved one's eventual outcome. CONCLUSIONS: After SABI, prognostic uncertainty almost transcends the concept of choice. Families who proceeded with a tracheostomy saw it as the only option at the time. High-quality communication may mitigate the stress surrounding this high-stakes decision.

Outcomes After Tracheostomy in Patients with Severe Acute Brain Injury: A Systematic Review and Meta-Analysis.

OBJECTIVE: To synthesize reported long-term outcomes in patients undergoing tracheostomy after severe acute brain injury (SABI). METHODS: We systematically searched PubMed, EMBASE, and Cochrane Library for studies in English, German, and Spanish between 1990 and 2019, reporting outcomes in patients with SABI who underwent tracheostomy. We adhered to the preferred reporting items for systematic reviews and meta-analyses guidelines and the meta-analyses of observational studies in epidemiology guidelines. We excluded studies reporting on less than 10 patients, mixed populations with other neurological diseases, or studies assessing highly select subgroups defined by age or procedures. Data were extracted independently by two investigators. Results were pooled using random effects modeling. The primary outcome was long-term functional outcome (mRS or GOS) at 6-12 months. Secondary outcomes included hospital and long-term mortality, decannulation rates, and discharge home rates. RESULTS: Of 1405 studies identified, 61 underwent full manuscript review and 19 studies comprising 35,362 patients from 10 countries were included in the meta-analysis. The primary outcome was available from five studies with 451 patients. At 6-12 months, about one-third of patients (30%; 95% confidence interval [CI] 17-48) achieved independence, and about one-third survived in a dependent state (36%, 95% CI 28-46%). The pooled short-term mortality for 19,048 patients was 12%, (95% CI 9-17%) with no significant difference between stroke (10%) and TBI patients (13%), and the pooled long-term mortality was 21% (95% CI 11-36). Decannulation occurred in 79% (95% CI 51-93%) of survivors. Heterogeneity was high for most outcome assessments (I2 > 75%). CONCLUSIONS: Our findings suggest that about one in three patients with SABI who undergo tracheostomy may eventually achieve independence. Future research is needed to understand the reasons for the heterogeneity between studies and to identify those patients with promising outcomes as well as factors influencing outcome.

An Unusual Case of Erotomania and Delusional Misidentification Syndrome.

Delusional misidentification syndromes and erotomania are rare entities, each with several distinct manifestations and no clearly defined treatment regimen. Here we expand upon an earlier literature review and describe the case of a 40-year-old woman with a history of bipolar I disorder who presented after an extended period of medication nonadherence with symptoms consistent with both of these conditions; she believed that the staff on the unit were in fact disguised celebrities and fictional characters, and she claimed to be married to a famous singer. The exact relationship of these symptoms (and indeed, even their basic etiologies) remains unclear; however, both delusional syndromes resolved with a combination of risperidone and lithium therapy. Although earlier literature has suggested pimozide as the most effective agent for treating delusional syndromes, given the more favorable side-effect profile of atypical versus typical antipsychotics, this case suggests a role for risperidone as a first-line treatment in such situations.