Hematologic and Inflammatory Predictors of Outcome in Patients with Brain Arteriovenous Malformations.

OBJECTIVE: This study investigated the prognostic value of admission blood counts for arteriovenous malformation (AVM) outcomes and compared admission blood counts for patients with ruptured and unruptured AVMs. METHODS: A retrospective analysis of patients who underwent surgical treatment for a ruptured cerebral AVM between February 1, 2014, and March 31, 2020, was conducted. The primary outcome was poor neurologic outcome, defined as a modified Rankin Scale score ≥2 in patients with unruptured AVMs or >2 in patients with ruptured AVMs. RESULTS: Of 235 included patients, 80 (34%) had ruptured AVMs. At admission, patients with ruptured AVMs had a significantly lower mean (SD) hemoglobin level (12.78 [2.07] g/dL vs. 13.71 [1.60] g/dL, P < 0.001), hematocrit (38.1% [5.9%] vs. 40.7% [4.6%], P < 0.001), lymphocyte count (16% [11%] vs. 26% [10%], P < 0.001), and absolute lymphocyte count (1.41 [0.72] × 103/µL vs. 1.79 [0.68] × 103/µL, P < 0.001), and they had a significantly higher mean (SD) white blood cell count (10.4 [3.8] × 103/µL vs. 7.6 [2.3] × 103/µL, P < 0.001), absolute neutrophil count (7.8 [3.8] × 103/µL vs. 5.0 [2.5] × 103/µL, P < 0.001), and neutrophil count (74% [14%] vs. 64% [13%], P < 0.001). Among patients with unruptured AVMs, white blood cell count ≥6.4 × 103/µL and absolute neutrophil count ≥3.4 × 103/µL were associated with a favorable neurologic outcome, whereas hemoglobin level ≥13.4 g/dL was associated with an unfavorable outcome. Among patients with ruptured AVMs, hypertension was associated with a 3-fold increase in odds of a poor neurologic outcome. CONCLUSIONS: Patients with ruptured and unruptured AVMs present with characteristic profiles of hematologic and inflammatory parameters evident in their admission blood work.

Optimal PHASES Scoring for Risk Stratification of Surgically Treated Unruptured Aneurysms.

OBJECTIVE: The PHASES (Population, Hypertension, Age, Size, Earlier subarachnoid hemorrhage, Site) score was developed to facilitate risk stratification for management of unruptured intracranial aneurysms (UIAs). This study aimed to identify the optimal PHASES score cutoff for predicting neurologic outcomes in patients with surgically treated aneurysms. METHODS: All patients who underwent microneurosurgical treatment for UIA at a large quaternary center from January 1, 2014, to December 31, 2020, were retrospectively reviewed. Inclusion criteria included a modified Rankin Scale (mRS) score of ≤2 at admission. The primary outcome was 1-year mRS score, with a "poor" neurologic outcome defined as an mRS score >2. RESULTS: In total, 375 patients were included in the analysis. The mean (SD) PHASES score for the entire study population was 4.47 (2.67). Of 375 patients, 116 (31%) had a PHASES score ≥6, which was found to maximize prediction of poor neurologic outcome. Patients with PHASES scores ≥6 had significantly higher rates of poor neurologic outcome than patients with PHASES scores <6 at discharge (58 [50%] vs. 90 [35%], P = 0.005) and follow-up (20 [17%] vs. 18 [6.9%], P = 0.002). After adjusting for age, Charlson Comorbidity Index score, nonsaccular aneurysm, and aneurysm size, PHASES score ≥6 remained a significant predictor of poor neurologic outcome at follow-up (odds ratio, 2.75; 95% confidence interval, 1.42-5.36, P = 0.003). CONCLUSIONS: In this retrospective analysis, a PHASES score ≥6 was associated with significantly greater proportions of poor outcome, suggesting that awareness of this threshold in PHASES scoring could be useful in risk stratification and UIA management.

Tranexamic Acid Demonstrates Efficacy without Increased Risk for Venous Thromboembolic Events in Cranial Neurosurgery: Systematic Review of the Evidence and Current Applications in Nontraumatic Pathologies.

BACKGROUND: The cautionary stance normally taken towards tranexamic acid (TXA) is rooted in concerns regarding its complication profile, namely its purported risk for venous thromboembolic events (VTEs). In the present review, we intend to bring increased attention to TXA as a remarkably valuable tool that does not appear to increase the risk for VTE when used as indicated in select patients. METHODS: We queried three databases to identify reporting use of TXA during nontraumatic cranial neurosurgery procedures (excluded traumatic brain injury). Data gathered included VTE complications, deep venous thrombosis, use of allogeneic blood transfusions, estimated blood loss, and operative duration. RESULTS: Twenty-eight studies were deemed eligible for inclusion in the present meta-analysis, including nine studies on surgical resection of intracranial neoplasms, ten studies on aneurysmal subarachnoid hemorrhage, and nine studies on craniosynostosis. In brain tumor surgery, TXA appears to successfully reduce blood loss without predisposing patients to VTE or seizure (P < 0.01). However, it does not appear to reduce rates of vasospasm in aneurysmal subarachnoid hemorrhage (P = 0.27), and its administration is not associated with clinically meaningful differences in long term neurological outcomes. For pediatric patients undergoing craniosynostosis procedures, TXA similarly reduces blood loss (P < 0.01). Nonetheless, low dosing protocols should be used because they appear effective and the effects of high dose TXA in children have not been studied. CONCLUSIONS: TXA is an effective hemostatic agent that can be administered to reduce blood loss and transfusion requirements for a wide range of neurosurgical applications in a broad spectrum of patient populations.

Publication patterns of posters and oral presentations at the Annual Meeting of the Joint AANS/CNS Cerebrovascular Section.

OBJECTIVE: The American Association of Neurological Surgeons (AANS) and Congress of Neurological Surgeons (CNS) Joint Cerebrovascular (CV) Section serves as a centralized entity for the dissemination of information related to CV neurosurgery. The quality of scientific conferences, such as the CV Section's Society of NeuroInterventional Surgery Annual Meeting, can be gauged by the number of poster and oral presentations that are published in peer-reviewed journals. However, publication rates from the CV Section's meetings are unknown. The objective of this study was to assess the rate at which abstracts presented at the AANS/CNS CV Section Annual Meeting from 2014 to 2018 were subsequently published in peer-reviewed journals. METHODS: The abstract titles for all accepted poster and oral podium presentation abstracts from the 2014-2018 Annual Joint AANS/CNS CV Section Meetings were searched using PubMed. A match was defined as sufficient similarity between the abstract and its corresponding journal publication with regard to title, authors, methods, and results. Five-year impact factors (IFs) from Journal Citation Reports (JCR), the country of the corresponding author, and the number of citations in the Scopus database were obtained using the articles' digital object identifier when available, or the exact article title, journal, and year of publication. RESULTS: Of the 607 total poster and oral presentations from the 2014-2018 Annual Meetings of the AANS/CNS Joint CV Section, 46.29% (n = 281) have been published. Published articles received 3233 total citations for an average number of citations per article (± SD) of 10.89 ± 16.37. The average 5-year JCR IF of published studies was 4.64 ± 3.13. Additionally, 98.22% of published abstracts were in publication within 4 years from the time the abstract was presented. The most common peer-reviewed neurosurgical journals featuring these publications were the Journal of Neurosurgery, World Neurosurgery, the Journal of NeuroInterventional Surgery, Neurosurgery, and the Journal of Clinical Neuroscience. CONCLUSIONS: Nearly half of all poster and oral presentations at the annual meetings of the AANS/CNS Joint CV Section from 2014 to 2018 have been published in PubMed-indexed, peer-reviewed journals. The average number of citations per publication (10.89 ± 16.37) reflects the high quality of abstracts accepted for presentation. It is important to continuously assess the quality of research presented at national conferences to ensure that standards are being maintained for the advancement of clinical practice in a given area of medicine. Conference abstract publication rates in peer-reviewed journals represent a way in which research quality can be gauged, and the authors encourage others to conduct similar investigations in their subspecialty area of interest and/or practice.

Mortality After Microsurgical Treatment of Unruptured Intracranial Aneurysms in the Modern Era.

BACKGROUND: The incidence of mortality after treatment of unruptured intracranial aneurysms (UIAs) has been described historically. However, many advances in microsurgical treatment have since emerged, and most available data are outdated. We analyzed the incidence of mortality after microsurgical treatment of patients with UIAs treated in the past decade. METHODS: The medical records of all patients with UIAs who underwent elective treatment at our large quaternary center from January 1, 2014, to December 31, 2020, were reviewed retrospectively. We analyzed mortality at discharge and 1-year follow-up as the primary outcome using univariate to multivariable progression with P < 0.20 inclusion. RESULTS: During the 7-year study period, 488 patients (mean [SD] age = 58 [12] years) had UIAs treated microsurgically. Of these patients, 61 (12.5%) had a prior subarachnoid hemorrhage. One patient (0.2%) with a dolichoectatic vertebrobasilar aneurysm died while hospitalized, and 7 other patients (8 total; 1.6%) were determined to have died at 1-year follow-up (1 trauma, 2 myocardial infarction, 2 cerebrovascular accident, 1 pulmonary embolism, and 1 subdural hematoma complicated by abscess). On univariate analysis, significant risk factors for mortality at follow-up included diabetes mellitus, preoperative anticoagulant or antiplatelet use, aneurysm calcification, nonsaccular aneurysm, and higher American Society of Anesthesiologists grades (all P < 0.03). On multivariable logistic regression analysis, only nonsaccular aneurysms and higher American Society of Anesthesiologists grades were predictors of mortality. CONCLUSIONS: A low mortality rate is associated with recent microsurgical treatment of UIAs. However, nonsaccular aneurysms and higher American Society of Anesthesiologists grades appear to be predictors of mortality.

Cerebrospinal Fluid Biomarkers for Diagnosis and the Prognostication of Acute Ischemic Stroke: A Systematic Review.

Despite the high incidence and burden of stroke, biological biomarkers are not used routinely in clinical practice to diagnose, determine progression, or prognosticate outcomes of acute ischemic stroke (AIS). Because of its direct interface with neural tissue, cerebrospinal fluid (CSF) is a potentially valuable source for biomarker development. This systematic review was conducted using three databases. All trials investigating clinical and preclinical models for CSF biomarkers for AIS diagnosis, prognostication, and severity grading were included, yielding 22 human trials and five animal studies for analysis. In total, 21 biomarkers and other multiomic proteomic markers were identified. S100B, inflammatory markers (including tumor necrosis factor-alpha and interleukin 6), and free fatty acids were the most frequently studied biomarkers. The review showed that CSF is an effective medium for biomarker acquisition for AIS. Although CSF is not routinely clinically obtained, a potential benefit of CSF studies is identifying valuable biomarkers from the pathophysiologic microenvironment that ultimately inform optimization of targeted low-abundance assays from peripheral biofluid samples (e.g., plasma). Several important catabolic and anabolic markers can serve as effective measures of diagnosis, etiology identification, prognostication, and severity grading. Trials with large cohorts studying the efficacy of biomarkers in altering clinical management are still needed.

Middle meningeal artery embolization associated with reduced chronic subdural hematoma volume and midline shift in the acute postoperative period.

BACKGROUND: Middle meningeal artery (MMA) embolization for endovascular treatment of chronic subdural hematoma (cSDH) is growing in popularity. cSDH volume and midline shift were analyzed in the immediate postoperative window after MMA embolization. METHODS: A retrospective analysis of cSDHs managed via MMA embolization from January 1, 2018 to March 30, 2021 was performed at a large quaternary center. Pre- and postoperative cSDH volume and midline shift were quantified with CT. Postoperative CT was obtained 12 to 36 hours after embolization. Paired t-tests were used to determine significant reduction. Multivariate analysis was performed using logistic and linear regression for percent improvement from baseline volume. RESULTS: In total, 80 patients underwent MMA embolization for 98 cSDHs during the study period. The mean (SD) initial cSDH volume was 66.54 (34.67) mL, and the mean midline shift was 3.79 (2.85) mm. There were significant reductions in mean cSDH volume (12.1 mL, 95% CI 9.32 to 14.27 mL, P<0.001) and midline shift (0.80 mm, 95% CI 0.24 to 1.36 mm, P<0.001). In the immediate postoperative period, 22% (14/65) of patients had a>30% reduction in cSDH volume. A multivariate analysis of 36 patients found that preoperative antiplatelet and anticoagulation use was significantly associated with an expansion in volume (OR 0.028, 95% CI 0.000 to 0.405, P=0.03). CONCLUSION: MMA embolization is safe and effective for the management of cSDH and is associated with significant reductions in hematoma volume and midline shift in the immediate postoperative period.

A comprehensive assessment of self-reported symptoms among patients harboring an unruptured intracranial aneurysm.

Background: Approximately 3.2%-6% of the general population harbor an unruptured intracranial aneurysm (UIA). Ruptured aneurysms represent a significant healthcare burden, and preventing rupture relies on early detection and treatment. Most patients with UIAs are asymptomatic, and many of the symptoms associated with UIAs are nonspecific, which makes diagnosis challenging. This study explored symptoms associated with UIAs, the rate of resolution of such symptoms after microsurgical treatment, and the likely pathophysiology. Methods: A retrospective review of patients with UIAs who underwent microsurgical treatment from January 1, 2014, to December 31, 2020, at a single quaternary center were identified. Analyses included the prevalence of nonspecific symptoms upon clinical presentation and postoperative follow-up; comparisons of symptomatology by aneurysmal location; and comparisons of patient demographics, aneurysmal characteristics, and poor neurologic outcome at postoperative follow-up stratified by symptomatic versus asymptomatic presentation. Results: The analysis included 454 patients; 350 (77%) were symptomatic. The most common presenting symptom among all 454 patients was headache (n = 211 [46%]), followed by vertigo (n = 94 [21%]), cognitive disturbance (n = 68[15%]), and visual disturbance (n = 64 [14%]). Among 328 patients assessed for postoperative symptoms, 258 (79%) experienced symptom resolution or improvement. Conclusion: This cohort demonstrates that the clinical presentation of patients with UIAs can be associated with vague and nonspecific symptoms. Early detection is crucial to prevent aneurysmal subarachnoid hemorrhage. It is imperative that physicians not rule out aneurysms in the setting of nonspecific neurologic symptoms.

Analysis of the Weekend Effect at a High-Volume Center for the Treatment of Intracranial Aneurysms.

OBJECTIVE: The "weekend effect" is the negative effect on disease course and treatment resulting from being admitted to the hospital during a weekend. Whether the weekend effect is associated with worse outcomes for patients treated for aneurysmal subarachnoid hemorrhage (aSAH) is unknown. We assessed neurologic outcomes of patients with aSAH admitted during the weekend versus during the week. METHODS: A retrospective database was reviewed to identify all patients with aSAH who received open or endovascular treatment from August 1, 2007, to July 31, 2019, at a quaternary center. The primary outcome was a poor neurologic outcome (modified Rankin Scale score >2). Propensity adjustment included age, sex, treatment type, Hunt and Hess grade, and Charlson Comorbidity Index. RESULTS: A total of 1014 patients (women, 703 [69.3%]; men, 311 [30.7%]; mean age, 56 [standard deviation, 14]) met inclusion criteria; 726 (71.6%) had weekday admissions, and 288 (28.4%) had weekend admissions. There was no significant difference between patients with a weekday versus a weekend admission in mean (standard deviation) time to treatment (0.85 [1.29] vs. 0.93 [1.30] days, P = 0.10) or length of stay (19 [9] vs. 19 [9] days, P = 0.04). Total cost and rates of delayed cerebral ischemia and vasospasm were similar between the admission groups, both overall and within the open and endovascular treatment cohorts. After propensity adjustment, weekend admission was not a significant predictor of a modified Rankin Scale score greater than 2 (odds ratio [95% confidence interval]; 1.12 [0.85-1.49]; P = 0.4). CONCLUSION: No difference in neurologic outcomes was associated with weekend admission among this cohort of patients with aSAH.

Challenging access during flow diversion treatment of a giant cavernous ICA aneurysm.

A man in his 60s presented with severe ophthalmoparesis and loss of visual acuity in his right eye. He was found to have a giant aneurysm of the cavernous internal carotid artery (ICA). Treatment with a flow diverter was recommended. The aneurysm caused matricidal outflow restriction of the ICA. Microwire and microcatheter access through the aneurysm was challenging, requiring multiple wires, stentriever reduction, and more. Eventually, a construct of 3 Pipeline embolization devices was created across the aneurysm. Troubleshooting access across giant aneurysms is an important part of treatment. Informed consent was obtained for the procedure and for publication. The video can be found here: https://stream.cadmore.media/r10.3171/2022.7.FOCVID2258.

Safe dissection and complication avoidance for L1-2 interbody placement via a lateral access approach.

The lateral access approach for L1-2 interbody placement or other levels at or near the thoracolumbar junction may be difficult without proper knowledge and visualization of anatomy. Specifically, understanding where the fibers of the diaphragm travel and avoiding injury to the diaphragm are paramount. The video can be found here: https://stream.cadmore.media/r10.3171/2022.3.FOCVID2221.

Sphenoparietal Sinus Dural Arteriovenous Fistulas: A Series of 10 Patients.

BACKGROUND: Dural arteriovenous fistulas (DAVFs) of the sphenoparietal sinus or sphenoid wing region are uncommon lesions with unique and interesting angioarchitecture. Understanding appropriate anatomy and recognizing patterns provide important treatment implications. OBJECTIVE: To describe a single surgeon's experience with open surgical treatment of sphenoparietal sinus DAVFs, the surgical indications for this uncommon lesion, and the microsurgical techniques related to its treatment and to review the literature on its surgical treatment. METHODS: Consecutive cases of sphenoparietal sinus DAVF treatment conducted by a single surgeon over 24 years (1997-2020) were retrospectively reviewed. Published reports of similar cases were reviewed. RESULTS: Of 202 surgically treated DAVFs, 10 lesions in 10 patients were sphenoparietal sinus DAVFs. Four patients presented with intracranial hemorrhage, 3 with headache, and 2 with pulsatile tinnitus; 1 patient was incidentally identified as having a DAVF during treatment for a ruptured aneurysm. Most patients (7 of 10) had undergone endovascular embolization previously. Nine patients had Borden type III DAVFs and one had a Borden type II fistula. Surgery in all 10 patients resulted in angiographically confirmed fistula obliteration. Clinical outcomes at the last follow-up, measured by a modified Rankin Scale (mRS) score, were excellent in 6 patients (mRS ≤ 2) and poor in 1 patient (mRS ≥ 3); late outcomes were not available for 3 patients. CONCLUSION: Sphenoparietal sinus DAVFs are an uncommon anatomic subtype. Careful attention to angiographic detail leads to identification of the site of venous interruption and results in a high rate of surgical cure with excellent clinical outcomes.

Mini-Open Lateral Approach for Corpectomy in the Thoracolumbar Spine.

The thoracolumbar spine poses unique challenges when considering surgical treatment options. In the era of modern medicine, nonoperative treatments have become more available for pathology of the thoracolumbar spine, including infectious, oncologic, traumatic, and degenerative etiologies. However, surgery is often warranted in the presence of deformity or with spinal cord compression resulting in neurologic deficits. Traditionally, posterior or anterior approaches were used for surgical treatment in the thoracolumbar spine. The mini-open lateral approach for corpectomy in the thoracolumbar spine is relatively new but not yet widely utilized, is less invasive, and is a less morbid surgical option for treating what has historically been a challenging surgical location. A thorough understanding of the anatomy associated with this approach is essential to perform safe and successful surgery with this technique. This review outlines the preoperative and anatomical considerations, surgical technique, contraindications, potential complications, and clinical outcomes associated with performing corpectomies in the thoracolumbar spine via the mini-open lateral approach. This is a safe, successful, and appealing surgical option for appropriately selected patients with diseases of the thoracolumbar region.

Versatile use of catheter systems for deployment of the Pipeline embolization device: a comparison of biaxial and triaxial catheter systems.

BACKGROUND: A Pipeline embolization device (PED; Medtronic, Dublin, Ireland) can be deployed using either a biaxial or a triaxial catheter delivery system. OBJECTIVE: To compare the use of these two catheter delivery systems for intracranial aneurysm treatment with the PED. METHODS: A retrospective study of patients undergoing PED deployment with biaxial or triaxial catheter systems between 2014 and 2016 was conducted. Experienced neurointerventionalists performed the procedures. Patients who received multiple PEDs or adjunctive coils were excluded. The two groups were compared for PED deployment time, total fluoroscopy time, patient radiation exposure, complications, and cost. RESULTS: Eighty-two patients with 89 intracranial aneurysms were treated with one PED each. In 49 cases, PEDs were deployed using biaxial access; triaxial access was used in 33 cases. Time (min) from guide catheter run to PED deployment was significantly shorter in the biaxial group (24.0±18.7 vs 38.4±31.1, P=0.006) as was fluoroscopy time (28.8±23.0 vs 50.3±27.1, P=0.001). Peak radiation skin exposure (mGy) in the biaxial group was less than in the triaxial group (1243.7±808.2 vs 2074.6±1505.6, P=0.003). No statistically significant differences were observed in transient and permanent complication rates or modified Rankin Scale scores at 30 days. The triaxial access system cost more than the biaxial access system (average $3285 vs $1790, respectively). Occlusion rates at last follow-up (mean 6 months) were similar between the two systems (average 88.1%: biaxial, 89.2%: triaxial). CONCLUSION: Our results indicate near-equivalent safety and effectiveness between biaxial and triaxial approaches. Some reductions in cost and procedure time were noted with the biaxial system.