Comparing stand-alone endovascular embolization versus stereotactic radiosurgery in the treatment of arteriovenous malformations with Spetzler-Martin grades I-III: a propensity score matched study.

BACKGROUND: Arteriovenous malformations (AVMs) are uncommon cerebral lesions that can cause significant neurological complications. Surgical resection is the gold standard for treatment, but endovascular embolization and stereotactic radiosurgery (SRS) are viable alternatives. OBJECTIVE: To compare the outcomes of endovascular embolization versus SRS in the treatment of AVMs with Spetzler-Martin grades I-III. METHODS: This study combined retrospective data from 10 academic institutions in North America and Europe. Patients aged 1 to 90 years who underwent endovascular embolization or SRS for AVMs with Spetzler-Martin grades I-III between January 2010 and December 2023 were included. RESULTS: The study included 244 patients, including 84 who had endovascular embolization and 160 who had SRS. Before propensity score matching (PSM), complete obliteration at the last follow-up was achieved in 74.5% of the SRS group compared with 57.8% of the embolization group (OR=0.47; 95% CI 0.26 to 0.48; P=0.01). After propensity score matching, SRS still achieved significantly higher occlusion rates at last follow-up (78.9% vs 55.3%; OR=0.32; 95% CI 0.12 to 0.90; P=0.03).Hemorrhagic complications were higher in the embolization group than in the SRS group, although this difference did not reach statistical significance after PSM (13.2% vs 2.6%; OR=5.6; 95% CI 0.62 to 50.47; P=0.12). Similarly, re-treatment rate was higher in the embolization group (10.5% vs 5.3%; OR=2.11; 95% CI 0.36 to 12.31; P=0.40) compared with the SRS group. CONCLUSION: Our findings indicate that SRS has a significantly higher obliteration rate at last follow-up compared with endovascular embolization. Also, SRS has a higher tendency for fewer hemorrhagic complications and lower re-treatment rate. Further prospective studies are needed.

Predictors of Aneurysm Obliteration in Patients Treated with the WEB Device: Results of a Multicenter Retrospective Study.

BACKGROUND AND PURPOSE: Despite the numerous studies evaluating the occlusion rates of aneurysms following WEB embolization, there are limited studies identifying predictors of occlusion. Our purpose was to identify predictors of aneurysm occlusion and the need for retreatment. MATERIALS AND METHODS: This is a review of a prospectively maintained database across 30 academic institutions. We included patients with previously untreated cerebral aneurysms embolized using the WEB who had available intraprocedural data and long-term follow-up. RESULTS: We studied 763 patients with a mean age of 59.9 (SD, 11.7) years. Complete aneurysm occlusion was observed in 212/726 (29.2%) cases, and contrast stasis was observed in 485/537 (90.3%) of nonoccluded aneurysms. At the final follow-up, complete occlusion was achieved in 497/763 (65.1%) patients, and retreatment was required for 56/763 (7.3%) patients. On multivariable analysis, history of smoking, maximal aneurysm diameter, and the presence of an aneurysm wall branch were negative predictors of complete occlusion (OR, 0.5, 0.8, and 0.4, respectively). Maximal aneurysm diameter, the presence of an aneurysm wall branch, posterior circulation location, and male sex increase the chances of retreatment (OR, 1.2, 3.8, 3.0, and 2.3 respectively). Intraprocedural occlusion resulted in a 3-fold increase in the long-term occlusion rate and a 5-fold decrease in the retreatment rate (P < .001), offering a specificity of 87% and a positive predictive value of 85% for long-term occlusion. CONCLUSIONS: Intraprocedural occlusion can be used to predict the chance of long-term aneurysm occlusion and the need for retreatment after embolization with a WEB device. Smoking, aneurysm size, and the presence of an aneurysm wall branch are associated with decreased chances of successful treatment.

Treatment of large intracranial aneurysms using the Woven EndoBridge (WEB): a propensity score-matched analysis.

The Woven EndoBridge (WEB) device is primarily used for treating wide-neck intracranial bifurcation aneurysms under 10 mm. Limited data exists on its efficacy for large aneurysms. We aim to assess angiographic and clinical outcomes of the WEB device in treating large versus small aneurysms. We conducted a retrospective review of the WorldWide WEB Consortium database, from 2011 to 2022, across 30 academic institutions globally. Propensity score matching (PSM) was employed to compare small and large aneurysms on baseline characteristics. A total of 898 patients were included. There was no significant difference observed in clinical presentations, smoking status, pretreatment mRS, presence of multiple aneurysms, bifurcation location, or prior treatment between the two groups. After PSM, 302 matched pairs showed significantly lower last follow-up adequate occlusion rates (81% vs 90%, p = 0.006) and higher retreatment rates (12% vs 3.6%, p < 0.001) in the large aneurysm group. These findings may inform treatment decisions and patient counseling. Future studies are needed to further explore this area.

Symptomatic intracerebral hemorrhage in proximal and distal medium middle cerebral artery occlusion patients treated with mechanical thrombectomy.

BACKGROUND: Acute ischemic stroke (AIS) caused by distal medium vessel occlusions (DMVOs) represents a significant proportion of overall stroke cases. While intravenous thrombolysis (IVT) has been a primary treatment, advancements in endovascular procedures have led to increased use of mechanical thrombectomy (MT) in DMVO stroke patients. However, symptomatic intracerebral hemorrhage (sICH) remains a critical complication of AIS, particularly after undergoing intervention. This study aims to identify factors associated with sICH in DMVO stroke patients undergoing MT. METHODS: This retrospective analysis utilized data from the Multicenter Analysis of Distal Medium Vessel Occlusions: Effect of Mechanical Thrombectomy (MAD-MT) registry, involving 37 centers across North America, Asia, and Europe. Middle cerebral artery (MCA) DMVO stroke patients were included. The primary outcome measured was sICH, as defined per the Heidelberg Bleeding Classification. Univariable and multivariable logistic regression were used to identify factors independently associated with sICH. RESULTS: Among 1708 DMVO stroke patients, 148 (8.7%) developed sICH. Factors associated with sICH in DMVO patients treated with MT included older age (adjusted odds ratio (aOR) 1.01, 95% confidence interval (95% CI) 1.00 to 1.03, P=0.048), distal occlusion site (M3, M4) compared with medium occlusions (M2) (aOR 1.71, 95% CI 1.07 to 2.74, P=0.026), prior use of antiplatelet drugs (aOR 2.06, 95% CI 1.41 to 2.99, P<0.001), lower Alberta Stroke Program Early CT Scores (ASPECTS) (aOR 0.75, 95% CI 0.66 to 0.84, P<0.001), higher preoperative blood glucose level (aOR 1.00, 95% CI 1.00 to 1.01, P=0.012), number of passes (aOR 1.27, 95% CI 1.15 to 1.39, P<0.001), and successful recanalization (Thrombolysis In Cerebral Infarction (TICI) 2b-3) (aOR 0.43, 95% CI 0.28 to 0.66, P<0.001). CONCLUSION: This study provides novel insight into factors associated with sICH in patients undergoing MT for DMVO, emphasizing the importance of age, distal occlusion site, prior use of antiplatelet drugs, lower ASPECTS, higher preoperative blood glucose level, and procedural factors such as the number of passes and successful recanalization. Pending confirmation, consideration of these factors may improve personalized treatment strategies.

Antithrombotic Therapy in Cerebral Cavernous Malformations: A Systematic Review, Meta-Analysis, and Network Meta-Analysis.

BACKGROUND: Cerebral cavernous malformations are complex vascular anomalies in the central nervous system associated with a risk of intracranial hemorrhage. Traditional guidelines have been cautious about the use of antithrombotic therapy in this patient group, citing concerns about potential bleeding risk. However, recent research posits that antithrombotic therapy may actually be beneficial. This study aims to clarify the association between antithrombotic therapy, including antiplatelet and anticoagulant medications, and the risk of intracranial hemorrhage in patients with cerebral cavernous malformations. METHODS AND RESULTS: A comprehensive literature search was conducted in PubMed, Web of Science, and Scopus databases, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Nine single-center, nonrandomized cohort studies involving 2709 patients were included. Outcomes were analyzed using random-effects model, and a network meta-analysis was conducted for further insight. Of the 2709 patients studied, 388 were on antithrombotic therapy. Patients on antithrombotic therapy had a lower risk of presenting with intracranial hemorrhage (odds ratio [OR], 0.56 [95% CI, 0.45-0.7]; P<0.0001). In addition, the use of antithrombotic therapy was associated with lower risk of intracranial hemorrhage from a cerebral cavernous malformation on follow-up (OR, 0.21 [95% CI, 0.13-0.35]; P<0.0001). A network meta-analysis revealed a nonsignificant OR of 0.73 (95% CI, 0.23-2.56) when antiplatelet therapy was compared with anticoagulant therapy. CONCLUSIONS: Our study explores the potential benefits of antithrombotic therapy in cerebral cavernous malformations. Although the analysis suggests a possible role for antithrombotic agents, it is critical to note that the evidence remains preliminary. Fundamental biases in study design, such as ascertainment and assignment bias, limit the weight of our conclusions. Therefore, our findings should be considered hypothesis-generating and not definitive for clinical practice change.

The feasibility of mechanical thrombectomy versus medical management for acute stroke with a large ischemic territory.

BACKGROUND: Mechanical thrombectomy (MT) for acute ischemic stroke is generally avoided when the expected infarction is large (defined as an Alberta Stroke Program Early CT Score of <6). OBJECTIVE: To perform a meta-analysis of recent trials comparing MT with best medical management (BMM) for treatment of acute ischemic stroke with large infarction territory, and then to determine the cost-effectiveness associated with those treatments. METHODS: A meta-analysis of the RESCUE-Japan, SELECT2, and ANGEL-ASPECT trials was conducted using R Studio. Statistical analysis employed the weighted average normal method for calculating mean differences from medians in continuous variables and the risk ratio for categorical variables. TreeAge software was used to construct a cost-effectiveness analysis model comparing MT with BMM in the treatment of ischemic stroke with large infarction territory. RESULTS: The meta-analysis showed significantly better functional outcomes, with higher rates of patients achieving a modified Rankin Scale score of 0-3 at 90 days with MT as compared with BMM. In the base-case analysis using a lifetime horizon, MT led to a greater gain in quality-adjusted life-years (QALYs) of 3.46 at a lower cost of US$339 202 in comparison with BMM, which led to the gain of 2.41 QALYs at a cost of US$361 896. The incremental cost-effectiveness ratio was US$-21 660, indicating that MT was the dominant treatment at a willingness-to-pay of US$70 000. CONCLUSIONS: This study shows that, besides having a better functional outcome at 90-days' follow-up, MT was more cost-effective than BMM, when accounting for healthcare cost associated with treatment outcome.

Factors impacting neurosurgery residents' operative case volume: a nationwide survey.

OBJECTIVE: Neurological surgery residency remains one of the most competitive and longest specialties in terms of training in medicine. The Accreditation Council for Graduate Medical Education uses residents' case volume throughout residency as one of its measures for the quality of surgical training. The objective was to study the variability of residency case volume among US training programs and to analyze the factors that potentially influence that case volume. METHODS: In line with the Checklist for Reporting Results of Internet E-Surveys (CHERRIES) guidelines, an online survey regarding department size, case volume, number of residents per year, number of dedicated research years, presence of fellows, and resident case volume by the time of graduation was created using Google Forms and distributed to all neurosurgery residency program directors and coordinators in the US. RESULTS: A total of 97 of the 115 programs (84.3%) responded to the survey. Fifteen programs were excluded due to missing data or incomplete resident cohort at the time of the survey, and a total of 82 programs were included in the analysis. The average number of cases performed by residents as lead or senior surgeons by the time of graduation ranged from 900 to 2250 (median 1600 cases). The resident case volume did not have a significant correlation with the program case volume, number of operating attending neurosurgeons, number of residents, number of research years, or presence of fellows. The only factor that impacted the resident case volume was the number of cases performed per faculty. CONCLUSIONS: The number of cases performed by residents throughout residency varied significantly between programs. Although other factors play important roles in the quality of training, including autonomy, variation, and complexity of cases, the resident case volume is one of the only measurable factors. This study sheds some light on the factors that potentially influence neurosurgical resident case volume.

Stem cell therapy for traumatic brachial plexus injury.

Stem cell therapy is rapidly evolving, with preclinical studies showing various stem cell types successfully promoting peripheral nerve regeneration. Despite the lack of clinical studies demonstrating efficacy and safety, the number of commercial entities marketing and promoting this treatment direct to patients is also increasing. We describe three adult traumatic brachial plexus injury (BPI) patients who had stem cell therapies prior to consultation in a multidisciplinary brachial plexus clinic. No functional improvement was noted at long-term follow-up despite claims reported by the commercial entities. Considerations and implications of stem cell application in BPI patients are reviewed.

Health inequities and socioeconomic factors predicting the access to treatment for unruptured intracranial aneurysms in the USA in the last 20 years: interaction effect of race, gender, and insurance.

BACKGROUND: The literature suggests that minority racial and ethnic groups have lower treatment rates for unruptured intracranial aneurysms (UIA). It is uncertain how these disparities have changed over time. METHODS: A cross-sectional study using the National Inpatient Sample database covering 97% of the USA population was carried out. RESULTS: A total of 213 350 treated patients with UIA were included in the final analysis and compared with 173 375 treated patients with aneurysmal subarachnoid hemorrhage (aSAH) over the years 2000-2019. The mean (SD) age of the UIA and aSAH groups was 56.8 (12.6) years and 54.3 (14.1) years, respectively. In the UIA group, 60.7% were white patients, 10.2% were black patients, 8.6% were Hispanic, 2% were Asian or Pacific Islander, 0.5% were Native Americans, and 2.8% were others. The aSAH group comprised 48.5% white patients, 13.6% black patients, 11.2% Hispanics, 3.6% Asian or Pacific Islanders, 0.4% Native Americans, and 3.7% others. After adjusting for covariates, black patients (OR 0.637, 95% CI 0.625 to 0.648) and Hispanic patients (OR 0.654, 95% CI 0.641 to 0.667) had lower odds of treatment compared with white patients. Medicare patients had higher odds of treatment than private patients, while Medicaid and uninsured patients had lower odds. Interaction analysis showed that non-white/Hispanic patients with any insurance/no insurance had lower treatment odds than white patients. Multivariable regression analysis showed that the treatment odds of black patients has improved slightly over time, while the odds for Hispanic patients and other minorities have remained the same over time. CONCLUSION: This study from 2000 to 2019 shows that disparities in the treatment of UIA have persisted but have slightly improved over time for black patients while remaining constant for Hispanic patients and other minority groups.

Comparing treatment outcomes of various intracranial bifurcation aneurysms locations using the Woven EndoBridge (WEB) device.

BACKGROUND: The Woven EndoBridge (WEB) device has Food and Drug Administration approval for treatment of wide-necked intracranial bifurcation aneurysms. The WEB device has been shown to result in adequate occlusion in bifurcation aneurysms overall, but its usefulness in the individual bifurcation locations has been evaluated separately only in few case series, which were limited by small sample sizes. OBJECTIVE: To compare angiographic and clinical outcomes after treatment of bifurcation aneurysms at various locations, including anterior communicating artery (AComA), anterior cerebral artery (ACA) bifurcation distal to AComA, basilar tip, internal carotid artery (ICA) bifurcation, and middle cerebral artery (MCA) bifurcation aneurysms using the WEB device. METHODS: A retrospective cohort analysis was conducted at 22 academic institutions worldwide to compare treatment outcomes of patients with intracranial bifurcation aneurysms using the WEB device. Data include patient and aneurysm characteristics, procedural details, angiographic and functional outcomes, and complications. RESULTS: A total of 572 aneurysms were included. MCA (36%), AComA (35.7%), and basilar tip (18.9%) aneurysms were most common. The rate of adequate aneurysm occlusion was significantly higher for basilar tip (91.6%) and ICA bifurcation (96.7%) aneurysms and lower for ACA bifurcation (71.4%) and AComA (80.6%) aneurysms (p=0.04). CONCLUSION: To our knowledge, this is the most extensive study to date that compares the treatment of different intracranial bifurcation aneurysms using the WEB device. Basilar tip and ICA bifurcation aneurysms showed significantly higher rates of aneurysm occlusion than other locations.

Microsurgical clipping and endovascular management of unruptured anterior circulation aneurysms: how age, frailty, and comorbidity indexes influence outcomes.

OBJECTIVE: Frailty is one of the important factors in predicting the outcomes of surgery. Many surgical specialties have adopted a frailty assessment in the preoperative period for prognostication; however, there are limited data on the effects of frailty on the outcomes of cerebral aneurysms. The object of this study was to find the effect of frailty on the surgical outcomes of anterior circulation unruptured intracranial aneurysms (UIAs) and compare the frailty index with other comorbidity indexes. METHODS: A retrospective study was performed utilizing the National Inpatient Sample (NIS) database (2016-2018). The Hospital Frailty Risk Score (HFRS) was used to assess frailty. On the basis of the HFRS, the whole cohort was divided into low-risk (0-5), intermediate-risk (> 5 to 15), and high-risk (> 15) frailty groups. The analyzed outcomes were nonhome discharge, complication rate, extended length of stay, and in-hospital mortality. RESULTS: In total, 37,685 patients were included in the analysis, 5820 of whom had undergone open surgical clipping and 31,865 of whom had undergone endovascular management. Mean age was higher in the high-risk frailty group than in the low-risk group for both clipping (63 vs 55.4 years) and coiling (64.6 vs 57.9 years). The complication rate for open surgical clipping in the high-risk frailty group was 56.1% compared to 0.8% in the low-risk group. Similarly, for endovascular management, the complication rate was 60.6% in the high-risk group compared to 0.3% in the low-risk group. Nonhome discharges were more common in the high-risk group than in the low-risk group for both open clipping (87.8% vs 19.7%) and endovascular management (73.1% vs 4.4%). Mean hospital charges for clipping were $341,379 in the high-risk group compared to $116,892 in the low-risk group. Mean hospital charges for coiling were $392,861 in the high-risk frailty group and $125,336 in the low-risk group. Extended length of stay occurred more frequently in the high-risk frailty group than in the low-risk group for both clipping (82.9% vs 10.7%) and coiling (94.2% vs 12.7%). Frailty had higher area under the receiver operating characteristic curve values than those for other comorbidity indexes and age in predicting outcomes. CONCLUSIONS: Frailty affects surgical outcomes significantly and outperforms age and other comorbidity indexes in predicting outcome. It is imperative to include frailty assessment in preoperative planning.

Intrasaccular flow disruption for ruptured aneurysms: an international multicenter study.

BACKGROUND: The Woven EndoBridge (WEB) device is a novel intrasaccular flow disruptor tailored for bifurcation aneurysms. We aim to describe the degree of aneurysm occlusion at the latest follow-up, and the rate of complications of aneurysms treated with the WEB device stratified according to rupture status. METHODS: Our data were taken from the WorldWideWeb Consortium, an international multicenter cohort including patients treated with the WEB device. Aneurysms were classified into two groups: ruptured and unruptured. We compared clinical and radiologic outcomes of both groups. Propensity score matching (PSM) was done to match according to age, gender, bifurcation, location, prior treatment, neck, height, dome width, daughter sac, incorporated branch, pretreatment antiplatelets, and last imaging follow-up. RESULTS: The study included 676 patients with 691 intracranial aneurysms (529 unruptured and 162 ruptured) treated with the WEB device. The PSM analysis had 55 pairs. In both the unmatched (85.8% vs 84.3%, p=0.692) and matched (94.4% vs 83.3%, p=0.066) cohorts there was no significant difference in the adequate occlusion rate at the last follow-up. Likewise, there were no significant differences in both ischemic and hemorrhagic complications between the two groups. There was no documented aneurysm rebleeding after WEB device implantation. CONCLUSION: There was no significant difference in both the radiologic outcomes and complications between unruptured and ruptured aneurysms. Our findings support the feasibility of treatment of ruptured aneurysms with the WEB device.

Endovascular Management of Hemorrhagic Stroke.

Significant advances in endovascular neurosurgery tools, devices, and techniques are changing the approach to the management of acute hemorrhagic stroke. The endovascular treatment of intracranial aneurysms emerged in the early 1990s with Guglielmi detachable coils, and since then, it gained rapid popularity that surpassed open surgery. Stent-assisted coiling and balloon remodeling techniques have made the treatment of wide-necked aneurysms more durable. With the introduction of flow diverters and flow disrupters, many aneurysms with complex geometrics can now be reliably managed. Arteriovenous malformations and fistulae can also benefit from endovascular therapy by embolization using n-butyl cyanoacrylate (NBCA), Onyx, polyvinyl alcohol (PVA), and coils. In this article, we describe the role of endovascular treatment for the most common causes of intracerebral and subarachnoid hemorrhages, particularly ruptured aneurysms and vascular malformations.

Repeat Flow Diversion for Cerebral Aneurysms Failing Prior Flow Diversion: Safety and Feasibility From Multicenter Experience.

BACKGROUND: Aneurysmal persistence after flow diversion (FD) occurs in 5% to 25% of aneurysms, which may necessitate retreatment. There are limited data on safety/efficacy of repeat FD-a frequently utilized strategy in such cases. METHODS: A series of consecutive patients undergoing FD retreatment from 15 centers were reviewed (2011-2019), with inclusion criteria of repeat FD for the same aneurysm at least 6 months after initial treatment, with minimum of 6 months post-retreatment imaging. The primary outcome was aneurysmal occlusion, and secondary outcome was safety. A multivariable logistic regression model was constructed to identify predictors of incomplete occlusion (90%-99% and <90% occlusion) versus complete occlusion (100%) after retreatment. RESULTS: Ninety-five patients (median age, 57 years; 81% women) harboring 95 aneurysms underwent 198 treatment procedures. Majority of aneurysms were unruptured (87.4%), saccular (74.7%), and located in the internal carotid artery (79%; median size, 9 mm). Median elapsed time between the first and second treatment was 12.2 months. Last available follow-up was at median 12.8 months after retreatment, and median 30.6 months after the initial treatment, showing complete occlusion in 46.2% and near-complete occlusion (90%-99%) in 20.4% of aneurysms. There was no difference in ischemic complications following initial treatment and retreatment (4.2% versus 4.2%; P>0.99). On multivariable regression, fusiform morphology had higher nonocclusion odds after retreatment (odds ratio [OR], 7.2 [95% CI, 1.97-20.8]). Family history of aneurysms was associated with lower odds of nonocclusion (OR, 0.18 [95% CI, 0.04-0.78]). Likewise, positive smoking history was associated with lower odds of nonocclusion (OR, 0.29 [95% CI, 0.1-0.86]). History of hypertension trended toward incomplete occlusion (OR, 3.10 [95% CI, 0.98-6.3]), similar to incorporated branch into aneurysms (OR, 2.78 [95% CI, 0.98-6.8]). CONCLUSIONS: Repeat FD for persistent aneurysms carries a reasonable success/safety profile. Satisfactory occlusion (100% and 90%-99% occlusion) was encountered in two-thirds of patients, with similar complications between the initial and subsequent retreatments. Fusiform morphology was the strongest predictor of retreatment failure.

Flow Diversion for Middle Cerebral Artery Aneurysms: An International Cohort Study.

BACKGROUND: Open surgery has traditionally been preferred for the management of bifurcation middle cerebral artery (MCA) aneurysms. Flow diverting stents present a novel endovascular strategy for aneurysm treatment. OBJECTIVE: To add to the limited literature describing the outcomes and complications in the use of flow diverters for the treatment of these complex aneurysms. METHODS: This is a multicenter retrospective review of MCA bifurcation aneurysms undergoing flow diversion. We assessed post-treatment radiological outcomes and both thromboembolic and hemorrhagic complications. RESULTS: We reviewed the outcomes of 54 aneurysms treated with flow diversion. Four (7.4%) of the aneurysms had a history of rupture (3 remote and 1 acute). Fourteen (25.9%) of the aneurysms already underwent either open surgery or coiling prior to flow diversion. A total of 36 out of the 45 aneurysms (80%) with available follow-up data had adequate aneurysm occlusion with a median follow-up time of 12 mo. There were no hemorrhagic complications but 16.7% (9/54) had thromboembolic complications. CONCLUSION: Flow diverting stents may be a viable option for the endovascular treatment of complex bifurcation MCA aneurysms. However, compared to published series on the open surgical treatment of this subset of aneurysms, flow diversion has inferior outcomes and are associated with a higher rate of complications.

Venous Thromboembolism Prophylaxis in Elective Neurosurgery: A Survey of Board-Certified Neurosurgeons in the United States and Updated Literature Review.

BACKGROUND: Venous thromboembolism (VTE) remains the single most important preventable cause of morbidity and mortality following neurosurgical procedures, with an incidence of approximately 16%. In the absence of stringent guidelines, the variation in current practice patterns could be considerable and was the underlying basis for this study. OBJECTIVES: Our objective is to evaluate the modality of thromboprophylaxis used by neurosurgeons. METHODS: In line with "CHERRIES" (Checklist for Reporting Results of Internet E-Surveys) guidelines, an online survey regarding postoperative VTE prophylaxis following elective neurosurgical procedures was created using Google Forms and distributed to 1500 board-certified neurosurgeons in the United States. RESULTS: A total of 370 board-certified neurosurgeons (24.7%) responded to the survey. Sequential compression device was the only primary method of thromboprophylaxis used by 27.2% and 26.5% of respondents after elective craniotomy for tumor resection and spine surgery, respectively. Of the chemical prophylaxis, subcutaneous heparin 5000 U every 8 hours was the most commonly used medication followed by enoxaparin 40 mg daily. Most responders were comfortable starting chemical prophylaxis on postoperative day 1, followed by day 2 and day 3 in both types of surgeries. The mean postoperative time of chemical prophylaxis initiation was significantly more delayed by respondents with longer years in practice. CONCLUSIONS: This study highlights the variation in practice between neurosurgeons in managing postoperative VTE prophylaxis after elective spine and cranial surgeries. In lieu of this variation, our results showed that most neurosurgeons are comfortable starting chemical prophylaxis as soon as postoperative day 1 following both types of procedures.

Does preoperative embolization improve outcomes of meningioma resection? A systematic review and meta-analysis.

Current evidence regarding the benefit of preoperative embolization (POE) of meningiomas is inconclusive. This systematic review and meta-analysis aims to evaluate the safety profile of the procedure and to compare outcomes in embolized versus non-embolized meningiomas. PubMed was queried for studies after January 1990 reporting outcomes of POE. Pertinent variables were extracted and synthesized from eligible articles. Heterogeneity was assessed using I2, and random-effects model was employed to calculate pooled 95% CI effect sizes. Publication bias was assessed using funnel plots and Harbord's and Begg's tests. Meta-analyses were used to assess estimated blood loss and operative duration (mean difference; MD), gross-total resection (odds ratio; OR), and postsurgical complications and postsurgical mortality (risk difference; RD). Thirty-four studies encompassing 1782 preoperatively embolized meningiomas were captured. The pooled immediate complication rate following embolization was 4.3% (34 studies, n = 1782). Although heterogeneity was moderate to high (I2 = 35-86%), meta-analyses showed no statistically significant differences in estimated blood loss (8 studies, n = 1050, MD = 13.9 cc, 95% CI = -101.3 to 129.1), operative duration (11 studies, n = 1887, MD = 2.4 min, 95% CI = -35.5 to 30.8), gross-total resection (6 studies, n = 1608, OR = 1.07, 95% CI = 0.8-1.5), postsurgical complications (12 studies, n = 2060, RD = 0.01, 95% CI = -0.04 to 0.07), and postsurgical mortality (12 studies, n = 2060, RD = 0.01, 95% CI = 0-0.01). Although POE is relatively safe, no clear benefit was observed in operative and postoperative outcomes. However, results must be interpreted with caution due to heterogeneity and selection bias between studies. Well-controlled future investigations are needed to define the patient population most likely to benefit from the procedure.

An Analysis of Trends in National Residency Matching Program Match Data for Orthopedic Surgery.

Due to electronic residency applications, US Medical Licensing Examination Step 1 scores are frequently used by orthopedic surgery program directors to screen applicants. Prospective applicants therefore often use Step 1 scores as a proxy for specialty competitiveness. The goal of this investigation was two-fold: (1) to determine whether trends in Step 1 scores are indicative of trends in competitiveness of orthopedic surgery and (2) to report the characteristics that optimize a US medical student's match success. A retrospective review of published National Resident Matching Program data from 2009 to 2018 was performed for orthopedic surgery residency applicants. Additional data from the Charting Outcomes reports were used for specific analyses of applicant characteristics. From 2009 to 2018, the number of orthopedic surgery residency positions grew at an annual rate of 1.51% (95% confidence interval [CI], 1.37% to 1.64%; P<.001), accommodating the 1.26% (95% CI, 0.63% to 1.90%; P=.006) annual increase in the number of applicants who ranked orthopedic surgery as their preferred specialty choice (only choice or first choice). There were no significant changes in the applicant-to-position ratio (95% CI, -0.85% to 0.37%; P=.483) or the match rate for US seniors who ranked orthopedic surgery as their preferred choice (95% CI, -0.23% to 0.87%; P=.313). Increases in mean Step 1 scores of matched orthopedic surgery applicants parallel national Step 1 growth trends (0.49% vs 0.44%, respectively). Although orthopedic surgery is currently a competitive specialty to match into, this has been the case since 2009. Increasing Step 1 scores of matched applicants is not unique to orthopedic surgery and should not be misinterpreted as a proxy for increasing competitiveness of the specialty. [Orthopedics. 2020;43(6):e616-e622.].

George Chance and Frank Holdsworth: Understanding Spinal Instability and the Evolution of Modern Spine Injury Classification Systems.

The concept of spinal cord injury has existed since the earliest human civilizations, with the earliest documented cases dating back to 3000 BC under the Egyptian Empire. Howevr, an understanding of this field developed slowly, with real advancements not emerging until the 20th century. Technological advancements including the dawn of modern warfare producing mass human casualties instigated revolutionary advancement in the field of spine injury and its management. Spine surgeons today encounter "Chance" and "Holdsworth" fractures commonly; however, neurosurgical literature has not explored the history of these physicians and their groundbreaking contributions to the modern understanding of spine injury. A literature search using a historical database, Cochrane, Google Scholar, and PubMed was performed. As needed, hospitals and native universities were contacted to add their original contributions to the literature. George Quentin Chance, a Manchester-based British physician, is well known to many as an eminent radiologist of his time who described the eponymous fracture in 1948. Sir Frank Wild Holdsworth (1904-1969), a renowned British orthopedic surgeon who laid a solid foundation for rehabilitation of spinal injuries under the aegis of the Miners' Welfare Commission, described in detail the management of thoraco-lumbar junctional rotational fracture. The work of these 2 men laid the foundation for today's understanding of spinal instability, which is central to modern spine injury classification and management algorithms. This historical vignette will explore the academic legacies of Sir Frank Wild Holdsworth and George Quentin Chance, and the evolution of spinal instability and spine injury classification systems that ensued from their work.

The Origins of Eponymous Aneurysm Clips: A Review.

Aneurysm clips are indispensable tools in the armamentarium of vascular neurosurgeons. The history of the development of aneurysm clips is witness to ingenuity and tenacity in treating a potentially devastating disease. Few know the stories of their innovators and the inspiration behind their designs. Hence, we present this historical vignette in an attempt to shed more light on the pioneers who shaped the evolution of aneurysm clips as we know them. A comprehensive literature search was performed using PubMed, Google Scholar, Google Books, and library historical archives, as well as personal communications with relatives, colleagues, and institutions of the surgeon-designers. We present the following aneurysm clip innovators and chronicle their biographies and contributions: Herbert Olivecrona (1891-1980), Frank Mayfield (1908-1991), Charles Drake (1920-1998), Joseph McFadden (1920-present), Thoralf Sundt Jr. (1930-1992), William M. Lougheed (1923-2004), William B. Scoville (1906-1984), Milton D. Heifetz (1921-2015), Gazi Yasargil (1925-present), Kenichiro Sugita (1932-1994), and Robert Spetzler (1944-present). Although this compilation of eponymous clips is by no means complete, we hope that it provides an informative historical perspective and an inspiration for aspiring neurosurgeons. The history of aneurysm surgery, an entity once deemed inoperable, teaches us the importance of innovation in medicine.