The Influence of Body Mass Index on Outcomes in Patients Undergoing Mechanical Thrombectomy for Anterior Circulation Large Vessel Occlusion: Institutional Experience and Meta-analysis.

BACKGROUND: An obesity paradox, whereby patients with higher body mass index (BMI) experience improved outcomes, has been described for ischemic stroke. It is unclear whether this applies to patients undergoing mechanical thrombectomy (MT) for large vessel occlusion (LVO). METHODS: Mechanical thrombectomies for anterior circulation LVO between 2015 and 2021 at a single institution were reviewed. Multivariable logistic regressions were used to determine the association between BMI and favorable functional outcome (90-day modified Rankin Scale 0-2), intracranial hemorrhage, and malignant middle cerebral infarction. A systematic review was performed to identify studies reporting the effect of BMI on outcomes among patients receiving MT for LVO. The data from the systematic review were combined with the institutional data by using a random effects model. RESULTS: The institutional cohort comprised 390 patients with a median BMI of 27 kg/m2. Most patients were obese [36.7% (BMI ≥ 30 kg/m2)], followed by overweight [30.5% (BMI ≥ 25 and < 30 kg/m2)], normal [27.9% (BMI ≥ 18.5 and < 25 kg/m2)], and underweight [4.9% (BMI < 18.5 kg/m2)]. As a continuous variable, BMI was not associated with any of the outcomes. When analyzing BMI ordinally, obesity was associated with lower odds of favorable 90-day modified Rankin Scale (odds ratio 0.42, 95% confidence interval 0.20-0.86). The systematic review identified three eligible studies comprising 1,348 patients for a total of 1,738 patients. In the random effects model, there was no association between obesity and favorable outcome (odds ratio 0.89, 95% confidence interval 0.63-1.24). CONCLUSIONS: Obesity is not associated with favorable outcomes in patients undergoing MT for LVO.

Machine learning prediction of malignant middle cerebral artery infarction after mechanical thrombectomy for anterior circulation large vessel occlusion.

OBJECTIVE: Prediction of malignant middle cerebral artery infarction (MMI) could identify patients for early intervention. We trained and internally validated a ML model that predicts MMI following mechanical thrombectomy (MT) for ACLVO. METHODS: All patients who underwent MT for ACLVO between 2015 - 2021 at a single institution were reviewed. Data was divided into 80% training and 20% test sets. 10 models were evaluated on the training set. The top 3 models underwent hyperparameter tuning using grid search with nested 5-fold CV to optimize the area under the receiver operating curve (AUROC). Tuned models were evaluated on the test set and compared to logistic regression. RESULTS: A total of 381 patients met the inclusion criteria. There were 50 (13.1%) patients who developed MMI. Out of the 10 ML models screened on the training set, the top 3 performing were neural network (median AUROC 0.78, IQR 0.72 - 0.83), support vector machine ([SVM] median AUROC 0.77, IQR 0.72 - 0.83), and random forest (median AUROC 0.75, IQR 0.68 - 0.81). On the test set, random forest (median AUROC 0.78, IQR 0.73 - 0.83) and neural network (median AUROC 0.78, IQR 0.73 - 0.83) were the top performing models, followed by SVM (median AUROC 0.77, IQR 0.70 - 0.83). These scores were significantly better than those for logistic regression (AUROC 0.72, IQR 0.66 - 0.78), individual risk factors, and the Malignant Brain Edema score (p < 0.001 for all). CONCLUSION: ML models predicted MMI with good discriminative ability. They outperformed standard statistical techniques and individual risk factors.

Venous Injury in Patients with Blunt Traumatic Brain Injury: Retrospective Analysis of a National Cohort.

BACKGROUND: Cerebral venous injury (CVI) includes injury to a dural venous sinus or major vein and leads to poorer outcomes for patients with blunt traumatic brain injury (TBI). We sought to identify the incidence, associated factors, and outcomes associated with CVI in a large national cohort. METHODS: Adult patients with blunt TBI were identified from the National Trauma Databank (2013-2017). Outcomes included inpatient mortality, discharge disposition, stroke, length of stay (LOS), intensive care unit LOS, and duration of mechanical ventilation. Multivariate regression models were used to identify the association between exposure variables and CVI, as well as each outcome. RESULTS: There were 619,659 patients with blunt TBI who met the inclusion criteria. CVI occurred in 1792 (0.3%) patients. Mixed intracranial injury type had the strongest association with CVI (odds ratio [OR] 2.89, 95% confidence interval [CI] 2.38-3.50), followed by isolated TBI (OR 1.76, 95% CI 1.54-2.02) and skull fracture (OR 1.72, 95% CI 1.55-1.91). CVI was associated with increased odds of mortality (OR 1.38, 95% CI 1.19-1.60), nonroutine discharge (OR 1.26, 95% CI 1.12-1.40), and stroke (OR 1.95, 95% CI 1.33-2.86). It was also associated with longer LOS (ß 2.02, 95% CI 1.55-2.50) and intensive care unit LOS (ß 0.14, 95% CI 0.13-0.16). Among locations of venous injury, superior sagittal sinus injury had significant associations with mortality (OR 2.93, 95% CI 1.62-5.30) and nonroutine discharge disposition (OR 1.94, 95% CI 1.12-3.35), whereas the others did not. CONCLUSIONS: We identified a 0.3% incidence of CVI in all-comers with blunt TBI as well as several injury-related variables that may be used to guide investigation for dural venous sinus injury. CVI was associated with poorer outcomes, with superior sagittal sinus injury having the strongest association.

Comparison of the Safety, Efficacy, and Procedural Characteristics Associated with Proximal and Distal Radial Access for Diagnostic Cerebral Angiography.

OBJECTIVES: Radial access is an increasingly popular approach for performing cerebral angiography. There are two sites for radial artery puncture: proximal transradial access (pTRA) in the wrist and distal transradial access (dTRA) in the snuffbox. These approaches have not been directly compared. MATERIALS AND METHODS: Consecutive diagnostic cerebral angiograms performed at a single institution were retrospectively reviewed. Outcomes included fluoroscopy time, radiation dose, contrast volume, time to obtain access, procedure duration, and time to discharge home. Success rates as well as minor and major complication rates associated with each approach were also compared. Multivariate linear regression models were used to determine the relationship between access site and outcomes while adjusting for covariates. RESULTS: A total of 287 angiograms on 244 patients met the inclusion criteria. pTRA was associated with shorter fluoroscopy time (ß -2.54, 95% CI -4.18 - -0.9, p = 0.003) and lower radiation dose (ß -242.89, 95% CI -351.55 - -134.24, p < 0.001), but not contrast volume. Time to obtain access, procedure duration, and time to discharge home were similar between approaches. A total of 10 minor complications occurred with similar rates for each approach (8 for dTRA, 2 for pTRA, p = 0.168) and there were no major complications. The conversion rate to femoral access was low (1.05% overall) and did not differ with approach. CONCLUSION: dTRA and pTRA are associated with similarly high rates of safety and efficacy. Procedure duration, time to obtain access, and time to discharge did not differ between approaches.

Ten-Year Trend in Age, Sex, and Racial Disparity in tPA (Alteplase) and Thrombectomy Use Following Stroke in the United States.

Background and Purpose: IV tPA (intravenous thrombolysis with alteplase) and mechanical thrombectomy (MT) utilization increased in acute ischemic stroke hospitalizations in the United States over the last decade. It is uncertain whether this increase occurred equally across all age, sex, and racial groups. Methods: Adult acute ischemic stroke hospitalizations (weighted n=4 442 657) contained in the 2008 to 2017 National Inpatient Sample were identified using International Classification of Diseases codes. Proportions of hospitalizations with IV tPA and MT were computed according to age, sex, and race. Joinpoint and multivariable-adjusted logistic regression models were used to evaluate trends over time. Results: Across this period, 32.4% of all hospitalizations were in patients ≥80 years, and 64.7% of these were women. IV tPA and MT use differed by age with highest proportion of utilization of both treatments in patients aged 18 to 39 years (IV tPA, 12.3%) and lowest percentage in patients aged ≥90 years (IV tPA, 7.9%). Utilization of both procedures increased over time in all age groups, but the pace of increase was faster in patients ≥90 years compared with patients aged 18 to 39 years (MT: odds ratio, 1.25 [95% CI, 1.20­1.35] per unit increase in year, P interaction <0.001). Frequency of utilization of IV tPA and MT was lower in Black patients compared with White patients in most age groups. Usage of both procedures increased over time in all races and after 2015, IV tPA utilization was >10% in all demographic subgroups except in Black patients 60 to 79 years and Black patients ≥80 years. Analysis of race-by-time interaction revealed the Black-vs-White treatment gaps for IV tPA (odds ratio, 1.02 [95% CI, 1.01­1.03]) and MT (odds ratio, 1.08 [95% CI,1.05­1.12]) declined over time (both P interaction <0.01). Sex-related differences in IV tPA use were noted, but this gap also declined over time. Conclusions: Age- and sex-related treatment gaps in IV tPA and MT reduced over the last decade. Racial disparity in IV tPA and MT utilization persists with particularly lower frequency of usage of both acute stroke treatments in Black patients compared with White patients, but race-associated treatment gaps also declined over time.

Risk Factors and Outcomes Associated with Blunt Cerebrovascular Injury in Patients with Mild or Moderate Traumatic Brain Injury.

BACKGROUND: Blunt cerebrovascular injury (BCVI) represents a spectrum of traumatic injuries to the carotid and vertebral arteries that is an often-overlooked source of morbidity and mortality. Its incidence, risk factors, and effect on outcomes in patients with mild or moderate traumatic brain injury (mTBI) have not been studied independently. METHODS: The National Trauma Data Bank from 2013 to 2017 was queried to identify patients with mTBI who suffered blunt injuries. BCVI was identified using abbreviated injury scores and included blunt carotid artery injury (BCAI) and blunt vertebral artery injury (BVAI). A binary logistic regression was used to identify patient-related and injury-related factors associated with BCVI. Binary logistic regressions were also performed to evaluate the effect of BCVI on stroke, in-hospital mortality, nonroutine discharge disposition, total length of stay (LOS), intensive care unit LOS, and number of days mechanically ventilated. RESULTS: Of 485,880 patients with mTBI, there were 4,382 (0.9%) with BCVI. Cervical spine fracture was the strongest factor associated with BCAI (odds ratio [OR], 1.97; 95% confidence interval [95% CI], 1.77-2.19), followed by mandible fracture and basilar skull fracture. Cervical spine fracture also had the strongest association with BVAI (OR, 18.28; 95% CI, 16.47-20.28), followed by spinal cord injury and neck contusion. Stroke was more common in patients with BCAI (OR, 5.50; 95% CI, 4.19-7.21) and BVAI (OR, 7.238; 95% CI, 5.929-8.836). BVAI increased the odds of mortality, but BCAI did not. Both were associated with nonroutine discharge and increased LOS, intensive care unit LOS, and number of days mechanically ventilated. CONCLUSIONS: The incidence of BCVI in patients with mTBI is low, and it usually does not require invasive treatment. However, it is associated with greater odds of stroke and negative outcomes. Knowledge of risk factors for BCVI may tailor further investigation to aid prompt diagnosis.

The Effect of Timing of Intracranial Pressure Monitor Placement in Patients with Severe Traumatic Brain Injury.

BACKGROUND/OBJECTIVE: Intracranial pressure (ICP) monitor placement is indicated for patients with severe traumatic brain injury (sTBI) to minimize secondary brain injury. There is little evidence to guide the optimal timing of ICP monitor placement. METHODS: A retrospective cohort study using the National Trauma Data Bank (NTDB) from 2013 to 2017 was performed. The NTDB was queried to identify patients with sTBI who underwent external ventricular drain or intraparenchymal ICP monitor placement. Propensity score matching was used to create matched pairs of patients who underwent early compared to late ICP monitor placement using 6-h and 12-h cutoffs. The outcomes of interest were in-hospital mortality, non-routine discharge disposition, total length of stay (LOS), intensive care unit (ICU) LOS, and number of days mechanically ventilated. RESULTS: A total of 5057 patients with sTBI were included in the study. In-hospital mortality for patients with early compared to late ICP monitor placement was 33.6% and 30.4%, respectively (p = 0.049). The incidence of non-routine disposition was 92.6% in the within 6 h group and 94.4% in the late placement group (p = 0.037). Hospital LOS, ICU LOS, and number of days mechanically ventilated were significantly greater in the late ICP monitoring group. Similar results were seen when using a 12-h cutoff for late ICP monitor placement. In the Cox proportional hazards model, craniotomy (HR 1.097, 95% CI 1.037-1.160) and isolated intracranial injury (HR 1.128, 95% CI 1.055-1.207) were associated with early ICP monitor placement. Hypotension was negatively associated with early ICP monitor placement (HR 0.801, 95% CI 0.725-0.884). CONCLUSION: Despite a statistically marginal association between mortality and early ICP monitor placement, most outcomes were superior when ICP monitors were placed within 6 or 12 h of arrival. This may be due to earlier identification and treatment of intracranial hypertension.

The Obesity Paradox in Spontaneous Intracerebral Hemorrhage: Results from a Retrospective Analysis of the Nationwide Inpatient Sample.

BACKGROUND/OBJECTIVE: Mild obesity is associated with a survival benefit in cardiovascular and cerebrovascular disease. Only a few studies have analyzed the effect of obesity on outcomes after spontaneous intracerebral hemorrhage (ICH), and none have used a national US database. We sought to determine whether or not obesity was associated with outcomes and in-hospital complications following ICH. METHODS: The Nationwide Inpatient Sample was used to identify patients with ICH in the USA who were discharged between 2002 and 2011. The presence of obesity (body mass index [BMI] 30-39.9) or morbid obesity (BMI ≥ 40) was noted. The primary outcome of interest was in-hospital mortality, and secondary outcomes included non-routine discharge disposition, tracheostomy or gastrostomy placement, length of stay (LOS), inflation-adjusted hospital charges, and in-hospital complications. RESULTS: A total of 123,415 patients with ICH met the inclusion criteria, and the 10-year overall incidence of obesity was 4.5%. Between 2002 and 2011, the incidence of obesity increased from 1.9 to 4.4% and the incidence of morbid obesity increased from 0.7 to 3.2%. Both obese (OR 0.62, 95% CI 0.56-0.69) and morbidly obese (OR 0.76, 95% CI 0.66-0.88) patients had lower odds of inpatient mortality. Obese (OR 0.85, 95% CI 0.78-0.93) but not morbidly obese patients had lower odds of non-routine discharge. Morbidly obese patients were twice as likely to require a tracheostomy than non-obese patients (OR 2.07, 95% CI 1.62-2.66). Both obese and morbidly obese patients had higher total hospital charges and rates of pulmonary, renal, and venous thromboembolic complications. There was no difference in LOS according to body habitus. CONCLUSIONS: In patients with spontaneous ICH, obesity is associated with decreased in-hospital mortality but higher rates of in-hospital complications and greater total hospital charges. Non-morbid obesity carries lower odds of non-routine hospital discharge.

A Propensity Score-Matched Comparison of Readmission Rates Associated With Microsurgical Clipping and Endovascular Treatment of Ruptured Intracranial Aneurysms.

BACKGROUND: In the treatment of aneurysmal subarachnoid hemorrhage (aSAH), microsurgical clipping, and endovascular therapy (EVT) with coiling are modalities for securing the ruptured aneurysm. Little data is available regarding associated readmission rates. We sought to determine whether readmission rates differed according to treatment modality for ruptured intracranial aneurysms. METHODS: The Nationwide Readmissions Database (NRD) was used to identify adults who experienced aSAH and underwent clipping or EVT. Primary outcomes of interest were the incidences of 30- and 90-day readmissions (30dRA, 90dRA). Propensity score matching was used to generate matched pairs based on age, comorbidities, hospital volume, and hemorrhage severity. RESULTS: We identified 13,623 and 11,160 patients who were eligible for 30dRA and 90dRA analyses, respectively. Among the patients eligible for 30dRA and 90dRA, we created 4282 and 3518 propensity score-matched pairs, respectively. There was no difference in the incidence of 30dRA (12.4% for clipping versus 11.2% for EVT; P = .094). However, 90dRA occurred more frequently after clipping (22.5%) compared to EVT (19.7%; P = .003). Clipping was associated with poor outcome after 30dRA (odds ratio [OR] = 1.51, 95% confidence interval [CI] 1.21-1.88, P < .001) and after 90dRA (OR = 1.60, 95% CI 1.34-1.91, P = .001). Mean duration to readmission and cost of readmission did not vary, but clipping was associated with longer lengths of stay during readmission. CONCLUSIONS: Microsurgical clipping of ruptured aneurysms is associated with a greater incidence of 90dRA, but not 30dRA, compared to EVT. Poor outcomes after readmission are more common following clipping.

The risk factors, outcomes, and costs associated with venous thromboembolism after traumatic brain injury: a nationwide analysis.

Objective: We sought to identify risk factors for VTE following traumatic brain injury (TBI) and determine how venous thromboembolism (VTE) affects outcomes and costs using a national database.Methods: The Nationwide Inpatient Sample (NIS) was used to identify patients with TBI between 2002 and 2014. VTE was identified as any occurrence of deep venous thrombosis or pulmonary embolism. We investigated putative risk factors for VTE and determined the effect of VTE on outcomes including mortality and disposition.Results: 424,929 patients met the inclusion criteria. There were 16,690 (3.9%) patients who developed a VTE. The annual incidence of VTE increased from 2.2% in 2002 to 5.4% in 2014 (R2 = 0.992, p < .001). Older age, increasing number of comorbidities, craniotomy or craniectomy, and more severe injuries were associated with increased odds of developing VTE (p < .001 for all). Patients with VTE had decreased odds of in-hospital mortality (OR 0.53; 95% CI 0.50-0.57) and increased odds of non-routine disposition (OR 2.05; 95% CI 1.97-2.14), tracheostomy, and gastrostomy.Conclusion: To our knowledge, we provide the largest analysis of VTE in TBI. This entity appears to be increasing in frequency, which may merit new strategies for prevention.

The Incidence of Meningitis in Patients with Traumatic Brain Injury Undergoing External Ventricular Drain Placement: A Nationwide Inpatient Sample Analysis.

BACKGROUND/OBJECTIVE: Infection is the most common complication of external ventricular drain (EVD) placement. National trends in the annual incidence of meningitis among patients with traumatic brain injury (TBI) who have undergone EVD placement have not been reported. METHODS: The Nationwide Inpatient Sample was used to select adults with a primary diagnosis of TBI who underwent EVD placement between 2002 and 2011. Annual rates of meningitis among patients who underwent EVD placement were determined. We also calculated mortality rates and length of stay (LOS). Potential factors associated with meningitis were evaluated in a binary logistic regression analysis. RESULTS: Out of 1,571,927 adult discharges with a primary diagnosis of TBI between 2002 and 2011, 39,029 (2.5%) underwent EVD placement. Of these, 1544 (4.3%) patients developed meningitis. There was no significant trend in the annual incidence of meningitis (p = 0.88), mortality (p = 0.55), or mean LOS (p = 0.13) during the study period. Meningitis and mortality rates remained stable when stratifying patients by hospital volume. In the binary logistic regression, acquired immunodeficiency syndrome, sepsis, and cerebrospinal fluid leak were associated with meningitis. CONCLUSIONS: The incidence of meningitis in patients who underwent EVD placement remained stable between 2002 and 2011. Further prospective studies are needed to identify approaches for preventing these infections.

Causes, Predictors, and Trends of Unplanned Readmissions after Elective Endovascular Embolization of Cerebral Aneurysms.

BACKGROUND: 30- and 90-day readmissions (dRA) are being increasingly scrutinized as quality metrics for hospital and provider performances. Little information regarding risk factors for readmission after elective endovascular treatment (EVT) of an unruptured cerebral aneurysm (UCA) is available. METHODS: The Nationwide Readmissions Database was used to identify patients who underwent elective endovascular embolization of an unruptured aneurysm between 2010 and 2014. The primary outcomes of interest were unplanned readmissions occurring within 30 or 90 days of discharge. Binary logistic regressions were used to identify variables related to patients' demographics, comorbidities, and index hospital admission that were associated with 30dRA and 90dRA. RESULTS: A total of 8588 patients met the inclusion criteria for 30dRA analysis and 7289 patients were eligible for 90dRA analysis. The 5-year 30dRA and 90dRA readmission rates were 7.1% and 13.5%, respectively. The annual incidences of 30dRAs and 90dRAs between 2010 and 2014 decreased significantly (pooled odds ratio (OR) for 30dRA: .874, 95% confidence interval (CI) .765-.998; pooled OR for 90dRA: .841, 95% CI .755-.938). Patients in higher income quartiles experienced decreased odds of 30dRA and 90dRA. Nonroutine disposition following the index admission and greater comorbidity burdens were associated with higher likelihoods of both 30dRA and 90dRA. The presence of pulmonary or cardiac complications was associated with increased odds of 90dRA. CONCLUSION: Readmission rates after elective EVT of UCAs decreased between 2010 and 2014. We identified several novel risk factors for both 30dRAs and 90dRAs that can be used to identify patients who are at highest risk of readmission.

Cortical Vein Opacification for Risk Stratification in Anterior Circulation Endovascular Thrombectomy.

INTRODUCTION: There is continued interest in identifying factors that predict a favorable outcome after endovascular thrombectomy (EVT) for anterior circulation large vessel occlusion (ACLVO). We compared the predictive values of 2 different scoring systems for evaluating venous collateral circulation. METHODS: A retrospective review of patients who underwent EVT for ACLVO at a single institution was performed. Those who underwent preprocedural computed tomography angiography (CTA) were selected. The Cortical Vein Opacification Score (COVES) and Prognostic Evaluation based on Cortical vein score difference In Stroke (PRECISE) score were calculated from each patient's CTA. Our primary outcome of interest was the Modified Rankin Scale (mRS) score at 90 days. RESULTS: A total of 103 patients were included in the study (average age = 68.3 years, median National Institutes of Health Stroke Scale = 15). The mean time to reperfusion was 6.4 hours and Thrombolysis in Cerebral Infarction 2B or 3 reperfusion was achieved in 77.7% of cases. An unfavorable COVES score was significantly associated with an unfavorable (mRS 3-6) outcome (adjusted odds ratio [aOR]: 3.06; 95% confidence interval [CI] 1.15-8.13, P = .025), while an unfavorable PRECISE score was not (aOR: 1.02; 95% CI .37-2.80, P = .966). Based on the Receiver Operating Characteristic analysis, the COVES score had a sensitivity of 68.1%, specificity of 71.4%, and area under the curve (AUC) of .77. The PRECISE score had a sensitivity of 68.9%, specificity of 70.7%, and the AUC of .73. CONCLUSIONS: The COVES score, but not the PRECISE score, is associated with functional outcomes at 90 days after EVT for ACLVO.

Rehabilitation of hand function after spinal cord injury using a novel handgrip device: a pilot study.

BACKGROUND: Activity-based therapy (ABT) for patients with spinal cord injury (SCI), which consists of repetitive use of muscles above and below the spinal lesion, improves locomotion and arm strength. Less data has been published regarding its effects on hand function. We sought to evaluate the effects of a weekly hand-focused therapy program using a novel handgrip device on grip strength and hand function in a SCI cohort. METHODS: Patients with SCI were enrolled in a weekly program that involved activities with the MediSens (Los Angeles, CA) handgrip. These included maximum voluntary contraction (MVC) and a tracking task that required each subject to adjust his/her grip strength according to a pattern displayed on a computer screen. For the latter, performance was measured as mean absolute accuracy (MAA). The Spinal Cord Independence Measure (SCIM) was used to measure each subject's independence prior to and after therapy. RESULTS: Seventeen patients completed the program with average participation duration of 21.3 weeks. The cohort included patients with American Spinal Injury Association (ASIA) Impairment Scale (AIS) A (n = 12), AIS B (n = 1), AIS C (n = 2), and AIS D (n = 2) injuries. The average MVC for the cohort increased from 4.1 N to 21.2 N over 20 weeks, but did not reach statistical significance. The average MAA for the cohort increased from 9.01 to 21.7% at the end of the study (p = .02). The cohort's average SCIM at the end of the study was unchanged compared to baseline. CONCLUSIONS: A weekly handgrip-based ABT program is feasible and efficacious at increasing hand task performance in subjects with SCI.

Quantitative Data-driven Utilization of Hematologic Labs Following Lumbar Fusion.

STUDY DESIGN: Retrospective case series. SUMMARY OF BACKGROUND DATA: Large national inpatient databases estimate that approximately 200,000 lumbar fusions are performed annually in the United States alone. It is common for surgeons to routinely order postoperative hematologic studies to rule out postoperative anemia despite a paucity of data to support routine laboratory utilization. OBJECTIVE: To describe quantitative criteria to guide postoperative utilization of hematologic laboratory assessments. METHODS: A retrospective analysis of 490 consecutive lumbar fusion procedures performed at a single institution by 3 spine surgeons was performed. Inclusion criteria included instrumented and noninstrumented lumbar fusions performed for any etiology. Data were acquired on preoperative and postoperative hematocrit, platelets, and international normalized ratio as well as age, sex, number of levels undergoing operation, indication for surgery, and intraoperative blood loss. Multivariate logistic regression was performed to determine correlation to postoperative transfusion requirement. RESULTS: A total of 490 patients undergoing lumbar fusion were identified. Twenty-five patients (5.1%) required postoperative transfusion. No patients required readmission for anemia or transfusion. Multivariate logistic regression analysis demonstrated that reduced preoperative hematocrit and increased intraoperative blood loss were independent predictors of postoperative transfusion requirement. Intraoperative blood loss >1000 mL had an odds ratio of 8.9 (P=0.013), and preoperative hematocrit <35 had an odds ratio of 4.37 (P=0.008) of requiring a postoperative transfusion. CONCLUSIONS: Routine postoperative hematologic studies are not necessary in many patients. High intraoperative blood loss and low preoperative hematocrit were independent predictors of postoperative blood transfusion. Our results describe quantitative preoperative and intraoperative criteria to guide data-driven utilization of postoperative hematologic studies following lumbar fusion.

Development and Internal Validation of Machine Learning Models to Predict Mortality and Disability After Mechanical Thrombectomy for Acute Anterior Circulation Large Vessel Occlusion.

OBJECTIVE: Mechanical thrombectomy (MT) improves outcomes in patients with LVO but many still experience mortality or severe disability. We sought to develop machine learning (ML) models that predict 90-day outcomes after MT for LVO. METHODS: Consecutive patients who underwent MT for LVO between 2015-2021 at a Comprehensive Stroke Center were reviewed. Outcomes included 90-day favorable functional status (mRS 0-2), severe disability (mRS 4-6), and mortality. ML models were trained for each outcome using prethrombectomy data (pre) and with thrombectomy data (post). RESULTS: Three hundred and fifty seven patients met the inclusion criteria. After model screening and hyperparameter tuning the top performing ML model for each outcome and timepoint was random forest (RF). Using only prethrombectomy features, the AUCs for the RFpre models were 0.73 (95% CI 0.62-0.85) for favorable functional status, 0.77 (95% CI 0.65-0.86) for severe disability, and 0.78 (95% CI 0.64-0.88) for mortality. All of these were better than a standard statistical model except for favorable functional status. Each RF model outperformed Pre, SPAN-100, THRIVE, and HIAT scores (P < 0.0001 for all). The most predictive features were premorbid mRS, age, and NIHSS. Incorporating MT data, the AUCs for the RFpost models were 0.80 (95% CI 0.67-0.90) for favorable functional status, 0.82 (95% CI 0.69-0.91) for severe disability, and 0.71 (95% CI 0.55-0.84) for mortality. CONCLUSIONS: RF models accurately predicted 90-day outcomes after MT and performed better than standard statistical and clinical prediction models.

Machine learning for clinical outcome prediction in cerebrovascular and endovascular neurosurgery: systematic review and meta-analysis.

BACKGROUND: Machine learning (ML) may be superior to traditional methods for clinical outcome prediction. We sought to systematically review the literature on ML for clinical outcome prediction in cerebrovascular and endovascular neurosurgery. METHODS: A comprehensive literature search was performed, and original studies of patients undergoing cerebrovascular surgeries or endovascular procedures that developed a supervised ML model to predict a postoperative outcome or complication were included. RESULTS: A total of 60 studies predicting 71 outcomes were included. Most cohorts were derived from single institutions (66.7%). The studies included stroke (32), subarachnoid hemorrhage ((SAH) 16), unruptured aneurysm (7), arteriovenous malformation (4), and cavernous malformation (1). Random forest was the best performing model in 12 studies (20%) followed by XGBoost (13.3%). Among 42 studies in which the ML model was compared with a standard statistical model, ML was superior in 33 (78.6%). Of 10 studies in which the ML model was compared with a non-ML clinical prediction model, ML was superior in nine (90%). External validation was performed in 10 studies (16.7%). In studies predicting functional outcome after mechanical thrombectomy the pooled area under the receiver operator characteristics curve (AUROC) of the test set performances was 0.84 (95% CI 0.79 to 0.88). For studies predicting outcomes after SAH, the pooled AUROCs for functional outcomes and delayed cerebral ischemia were 0.89 (95% CI 0.76 to 0.95) and 0.90 (95% CI 0.66 to 0.98), respectively. CONCLUSION: ML performs favorably for clinical outcome prediction in cerebrovascular and endovascular neurosurgery. However, multicenter studies with external validation are needed to ensure the generalizability of these findings.

Comparison of Retroauricular and Reverse Question Mark Incisions for Decompressive Hemicraniectomy.

BACKGROUND: The retroauricular (RA) incision has several theoretical benefits compared with the reverse question mark (RQM) incision for decompressive hemicraniectomy (DHC), but limited data comparing the 2 exist. METHODS: Consecutive patients who underwent DHC between 2016 and 2022 and survived ≥30 days at a single institution were included. The primary outcome was wound complication within 30 days (30dWC) requiring reoperation. Secondary outcomes included 90-day wound complication (90dWC), craniectomy size in anterior-posterior (AP) and superior-inferior dimensions, distance from the inferior craniectomy margin to the middle cranial fossa (MCF), estimated blood loss (EBL), and operative duration. Multivariate analyses were performed for each outcome. RESULTS: A total of 110 patients (RA group: 27, RQM group: 83) were included. The incidence of 30dWC was 1.2% and 0 in the RQM and RA groups, respectively. The incidence of 90dWC was 2.4% and 3.7% in the RQM and RA groups, respectively. There was no difference in mean AP size (RQM: 15 cm, RA: 14.4 cm; P = 0.18), superior-inferior size (RQM: 11.8 cm, RA: 11.9 cm; P = 0.92), and distance from MCF (RQM: 15.4 mm, RA: 18 mm; P = 0.18). Mean EBL (RQM: 418 mL, RA: 314 mL; P = 0.36) and operative duration (RQM: 103 min, RA: 89 min; P = 0.14) were similar. There was no difference in cranioplasty wound complications, EBL, or operative duration. CONCLUSIONS: Wound complications are comparable between the RQM and RA incisions. The RA incision does not compromise craniectomy size or temporal bone removal.

Percutaneous embolization of sinus pericranii.

Sinus pericranii is a rare vascular anomaly involving a venous sinus that drains into a subgaleal collection of veins through an emissary vein. Data regarding presentation, management, and outcomes are limited to case reports and small case series. There are no technical videos detailing the technique for percutaneous embolization. We present the case of a child with an enlarging, symptomatic accessory type sinus pericranii with connection to the torcula, who underwent percutaneous embolization after unsuccessful transvenous embolization. Embolization was performed with 3.4 cc Onyx-34 under live fluoroscopy and serial control superior sagittal sinus venograms . Significant reduction of flow into the sinus pericranii was achieved and the lesion had nearly completely resolved at the 3-week follow-up. Percutaneous embolization of the sinus pericranii is a reasonable alternative to transvenous embolization, but additional data are needed to determine the optimal treatment. The technical details and practical considerations discussed here may help neurointerventionalists adopt this treatment. The video also includes references 1-4 which are relevant to this topic. neurintsurg;15/8/828/V1F1V1Video 1Case presentation and technique for percutaneous embolization of sinus pericranii.

Endovascular embolization for the treatment of epistaxis: Systematic review and meta-analysis.

BACKGROUND: Endovascular embolization (EE) is a treatment option for epistaxis refractory to first-line interventions. Data regarding embolization is limited to small case series and a meta-analysis has not been performed. METHODS: PubMed, Scopus, and EMBASE were used to identify studies that reported outcomes for at least 10 patients undergoing EE for epistaxis. Outcomes included procedural success, rebleeding, and complications. Pooled rates for each outcome were obtained with random effects models. RESULTS: A total of 44 studies comprising 1664 patients met the inclusion criteria. The mean age ranged from 28.1 to 67 years and there were 28.4% females. The pooled procedural success rate was 87% (95% CI 83.9-89.6, I2 = 53%). Age (OR 0.95, 95% CI 0.91-1) and hereditary hemorrhagic telangiectasia ([HHT], OR 0.97, 95% CI 0.96-0.99) were associated with decreased odds of success. The pooled rebleeding rate was 16.4% (95% CI 13.6-19.6, I2 = 48%), and HHT was associated with greater odds of rebleeding (OR 1.02, 95% CI 1-1.03). The pooled overall complication rate was 14.4% (95% CI 9.8-20.6, I2 = 85.8%). The pooled rates of stroke and vision loss were 2.1% (95% CI 1.5-3.1, I2 = 1.5%) and 1.8% (95% CI 1.2-2.6, I2 = 0%), respectively. CONCLUSION: EE for epistaxis has a high rate of procedural success. Interventionalists should be aware of the risk for rebleeding, especially among patients with HHT.