International controlled study of revascularization and outcomes following COVID-positive mechanical thrombectomy.

BACKGROUND AND PURPOSE: Previous studies suggest that mechanisms and outcomes in patients with COVID-19-associated stroke differ from those in patients with non-COVID-19-associated strokes, but there is limited comparative evidence focusing on these populations. The aim of this study, therefore, was to determine if a significant association exists between COVID-19 status with revascularization and functional outcomes following thrombectomy for large vessel occlusion (LVO), after adjustment for potential confounding factors. METHODS: A cross-sectional, international multicenter retrospective study was conducted in consecutively admitted COVID-19 patients with concomitant acute LVO, compared to a control group without COVID-19. Data collected included age, gender, comorbidities, clinical characteristics, details of the involved vessels, procedural technique, and various outcomes. A multivariable-adjusted analysis was conducted. RESULTS: In this cohort of 697 patients with acute LVO, 302 had COVID-19 while 395 patients did not. There was a significant difference (p < 0.001) in the mean age (in years) and gender of patients, with younger patients and more males in the COVID-19 group. In terms of favorable revascularization (modified Thrombolysis in Cerebral Infarction [mTICI] grade 3), COVID-19 was associated with lower odds of complete revascularization (odds ratio 0.33, 95% confidence interval [CI] 0.23-0.48; p < 0.001), which persisted on multivariable modeling with adjustment for other predictors (adjusted odds ratio 0.30, 95% CI 0.12-0.77; p = 0.012). Moreover, endovascular complications, in-hospital mortality, and length of hospital stay were significantly higher among COVID-19 patients (p < 0.001). CONCLUSION: COVID-19 was an independent predictor of incomplete revascularization and poor functional outcome in patients with stroke due to LVO. Furthermore, COVID-19 patients with LVO were more often younger and had higher morbidity/mortality rates.

Ischemic Stroke Occurs Less Frequently in Patients With COVID-19: A Multicenter Cross-Sectional Study.

BACKGROUND AND PURPOSE: The impact of coronavirus disease 2019 (COVID-19) on the occurrence of ischemic stroke has been the subject of increased speculation but has not been confirmed in large observational studies. We investigated the association between COVID-19 and stroke. METHODS: We performed a cross-sectional study involving patients discharged from a healthcare system in New York State, from January to April 2020. A mixed-effects logistic regression analysis and a propensity score-weighted analysis were used to control for confounders and investigate the association of COVID-19 with ischemic stroke. Similar techniques were used to detect the impact of concurrent COVID-19 infection on unfavorable outcomes for patients with stroke. RESULTS: Among 24 808 discharges, 2513 (10.1%) were diagnosed with COVID-19, and 566 (0.2%) presented with acute ischemic stroke. Patients diagnosed with COVID-19 were at one-quarter the odds of stroke compared with other patients (odds ratio, 0.25 [95% CI, 0.16-0.40]). This association was consistent in all age groups. Our results were robust in sensitivity analyses, including propensity score-weighted regression models. In patients presenting with stroke, concurrent infection with severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) was associated with higher case-fatality (odds ratio, 10.50 [95% CI, 3.54-31.18]) and a trend towards increased occurrence of discharge to rehabilitation (odds ratio, 2.45 [95% CI, 0.81-1.25]). CONCLUSIONS: Using a comprehensive cross-section of patients from a large NY-based healthcare system, we did not identify a positive association between ischemic stroke and COVID-19. However, patients with stroke with COVID-19 had worse outcomes compared with those without, with over a 9-fold increase in mortality. Although no definitive conclusions can be reached from our observational study, our data do not support the concerns for an epidemic of stroke in young adults with COVID-19.

Correlation of hospital magnet status with the quality of physicians performing neurosurgical procedures in New York State.

PURPOSE: The quality of physicians practicing in hospitals recognized for nursing excellence by the American Nurses Credentialing Center has not been studied before. We investigated whether Magnet hospital recognition is associated with higher quality of physicians performing neurosurgical procedures. MATERIALS AND METHODS: We performed a cohort study of patients undergoing neurosurgical procedures from 2009-2013, who were registered in the New York Statewide Planning and Research Cooperative System (SPARCS) database. Propensity score adjusted multivariable regression models were used to adjust for known confounders, with mixed effects methods to control for clustering at the facility level. An instrumental variable analysis was used to control for unmeasured confounding and simulate the effect of a randomized trial. RESULTS: During the study period, 185,277 patients underwent neurosurgical procedures, and met the inclusion criteria. Of these, 66,607 (35.6%) were hospitalized in Magnet hospitals, and 118,670 (64.4%) in non-Magnet institutions. Instrumental variable analysis demonstrated that undergoing neurosurgical operations in Magnet hospitals was associated with a 13.6% higher chance of being treated by a physician with superior performance in terms of mortality (95% CI, 13.2% to 14.1%), and a 4.3% higher chance of being treated by a physician with superior performance in terms of length-of-stay (LOS) (95% CI, 3.8% to 4.7%) in comparison to non-Magnet institutions. The same associations were present in propensity score adjusted mixed effects models. CONCLUSIONS: Using a comprehensive all-payer cohort of neurosurgical patients in New York State we identified an association of Magnet hospital recognition with superior physician performance.

Anesthesia Technique and Outcomes of Mechanical Thrombectomy in Patients With Acute Ischemic Stroke.

BACKGROUND AND PURPOSE: The impact of anesthesia technique on the outcomes of mechanical thrombectomy for acute ischemic stroke remains an issue of debate. We investigated the association of general anesthesia with outcomes in patients undergoing mechanical thrombectomy for ischemic stroke. METHODS: We performed a cohort study involving patients undergoing mechanical thrombectomy for ischemic stroke from 2009 to 2013, who were registered in the New York Statewide Planning and Research Cooperative System database. An instrumental variable (hospital rate of general anesthesia) analysis was used to simulate the effects of randomization and investigate the association of anesthesia technique with case-fatality and length of stay. RESULTS: Among 1174 patients, 441 (37.6%) underwent general anesthesia and 733 (62.4%) underwent conscious sedation. Using an instrumental variable analysis, we identified that general anesthesia was associated with a 6.4% increased case-fatality (95% confidence interval, 1.9%-11.0%) and 8.4 days longer length of stay (95% confidence interval, 2.9-14.0) in comparison to conscious sedation. This corresponded to 15 patients needing to be treated with conscious sedation to prevent 1 death. Our results were robust in sensitivity analysis with mixed effects regression and propensity score-adjusted regression models. CONCLUSIONS: Using a comprehensive all-payer cohort of acute ischemic stroke patients undergoing mechanical thrombectomy in New York State, we identified an association of general anesthesia with increased case-fatality and length of stay. These considerations should be taken into account when standardizing acute stroke care.

Does scope of practice correlate with the outcomes of craniotomy for tumor resection in children?

BACKGROUND: The relationship of scope of practice (predominantly adult, versus predominantly pediatric) with the outcomes of brain tumor surgery in children remains uncertain. We investigated the association of practice focus with the outcomes of neurosurgical oncology operations in pediatric patients. METHODS: We performed a cohort study of all pediatric patients (younger than 18 years old) who underwent craniotomies for tumor resections from 2009 to 2013 and were registered in the Statewide Planning and Research Cooperative System (SPARCS) database. In order to control for confounding, we used propensity score conditioning with mixed effects analysis to account for clustering at the hospital level. RESULTS: During the study period, there were 770 pediatric patients who underwent craniotomy for tumor resection and met the inclusion criteria. Of these, 370 (48.1%) underwent treatment by providers with predominantly adult practices and 400 (51.9%) by physicians who operated predominantly on children. Mixed-effects multivariable regression analysis demonstrated lack of association of predominantly adult practice with inpatient mortality (OR, 1.12; 95% CI, 0.48-2.58), and discharge to a facility (OR, 1.25; 95% CI, 0.77-2.03). These associations persisted in propensity-adjusted models. CONCLUSIONS: In a cohort of pediatric patients undergoing craniotomy for tumor resection from a comprehensive all-payer database, we did not demonstrate a difference in mortality, and discharge to a facility between providers with predominantly adult and predominantly pediatric practices.

Radiosurgery for Cerebral Arteriovenous Malformations in A Randomized Trial of Unruptured Brain Arteriovenous Malformations (ARUBA)-Eligible Patients: A Multicenter Study.

BACKGROUND AND PURPOSE: The benefit of intervention for patients with unruptured cerebral arteriovenous malformations (AVMs) was challenged by results demonstrating superior clinical outcomes with conservative management from A Randomized Trial of Unruptured Brain AVMs (ARUBA). The aim of this multicenter, retrospective cohort study is to analyze the outcomes of stereotactic radiosurgery for ARUBA-eligible patients. METHODS: We combined AVM radiosurgery outcome data from 7 institutions participating in the International Gamma Knife Research Foundation. Patients with ≥12 months of follow-up were screened for ARUBA eligibility criteria. Favorable outcome was defined as AVM obliteration, no postradiosurgery hemorrhage, and no permanently symptomatic radiation-induced changes. Adverse neurological outcome was defined as any new or worsening neurological symptoms or death. RESULTS: The ARUBA-eligible cohort comprised 509 patients (mean age, 40 years). The Spetzler-Martin grade was I to II in 46% and III to IV in 54%. The mean radiosurgical margin dose was 22 Gy and follow-up was 86 months. AVM obliteration was achieved in 75%. The postradiosurgery hemorrhage rate during the latency period was 0.9% per year. Symptomatic and permanent radiation-induced changes occurred in 11% and 3%, respectively. The rates of favorable outcome, adverse neurological outcome, permanent neurological morbidity, and mortality were 70%, 13%, 5%, and 4%, respectively. CONCLUSIONS: Radiosurgery may provide durable clinical benefit in some ARUBA-eligible patients. On the basis of the natural history of untreated, unruptured AVMs in the medical arm of ARUBA, we estimate that a follow-up duration of 15 to 20 years is necessary to realize a potential benefit of radiosurgical intervention for conservative management in unruptured patients with AVM.

Regional disparities in hospitalization charges for patients undergoing craniotomy for tumor resection in New York State: correlation with outcomes.

There is increasing regulatory pressure for cost containment in neuro-oncology, and rationalization of the observed regional disparities. We investigated the presence of such disparities in New York State and examined the impact of risk adjustment on the magnitude of this variation. We performed a cohort study involving patients with brain tumors (gliomas, metastases, or meningiomas), who underwent craniotomy for resection from 2009 to 2013, and were registered in the Statewide Planning and Research Cooperative System (SPARCS) database. A linear regression model was utilized for risk-adjustment of inpatient charges using socioeconomic factors and comorbidities. Hospitals with fewer than 20 craniotomies were excluded. 13,535 patients underwent treatment, including 5032 (37.2 %) gliomas, 4858 (35.9 %) metastases, and 3645 (26.9 %) meningiomas. Unadjusted median hospitalization charges ranged from $22,954 to $177,398 at the hospital level, and $30,086 to $159,281 at the county level. Despite extensive risk-adjustment we observed persistent disparities with median hospitalization charges ranging from $40,455 to $124,691 at the hospital level, and $53,999 to $94,844 at the county level. Analysis of variance (ANOVA) demonstrated that these disparities were significant at the facility and the county level (P < 0.0001). Increased charges were not associated with shorter LOS (r = 0.10, P = 0.41), or lower rates of death (r = 0.09, P = 0.46), and unfavorable discharge (r = 0.24, P = 0.06). Using a comprehensive all-payer cohort of patients with brain tumors in New York State we identified wide disparities at the hospital and the county level despite comprehensive risk-adjustment. Increased charges were not associated with shorter LOS, or lower rates of death and unfavorable discharge.

Scope of practice and outcomes of cerebrovascular procedures in children.

PURPOSE: The impact of scope of practice of providers (predominantly adult versus predominantly pediatric) on the outcomes of cerebrovascular procedures in children remains an issue of debate. We investigated the association of scope of practice with the outcomes of cerebrovascular interventions. METHODS: We performed a cohort study of all pediatric patients (younger than 18 years old) who underwent cerebrovascular procedures from 2009 to 2013 and were registered in the Statewide Planning and Research Cooperative System (SPARCS) database. In order to control for confounding, we used propensity score conditioning and mixed effects analysis to account for clustering at the hospital level. RESULTS: During the study period, there were 1243 pediatric patients who underwent cerebrovascular procedures and met the inclusion criteria. Of these, 631 (50.7 %) underwent treatment by providers with predominantly adult practices and 612 (49.3 %) by physicians who operated predominantly on children. The mixed-effects multivariable regression analysis demonstrated lack of association of predominantly adult practice with inpatient mortality (OR, 1.20; 95 % CI, 0.61-2.38), discharge to a facility (OR, 1.50; 95 % CI, 0.73-3.09), and length of stay (LOS) (adjusted difference, 0.003; 95 % CI, -0.09 to 0.10). These associations persisted in propensity-adjusted models. CONCLUSIONS: In a cohort of pediatric patients undergoing cerebrovascular procedures from a comprehensive all-payer database, we did not demonstrate a difference in mortality, discharge to a facility, and LOS between providers with predominantly adult and predominantly pediatric practices.

The Association of Insurance Status and Race With Transfers of Patients With Traumatic Brain Injury Initially Evaluated at Level III and IV Trauma Centers.

OBJECTIVE: To investigate the association of lack of insurance and African American race with the probability of transfer to level I/II trauma centers after evaluation in the emergency department of level III/IV trauma centers for traumatic brain injury (TBI). BACKGROUND: The influence of nonmedical factors on the disposition of TBI patients initially seen in less specialized institutions is debated. METHODS: We conducted a retrospective cohort study involving TBI patients who were registered in the National Trauma Data Bank between 2009 and 2011. Regression methods were used to investigate the association of insurance status and race with the disposition of TBI patients evaluated in less specialized trauma centers. RESULTS: During the study period, there were 26,031 TBI patients who were registered in the National Trauma Data Bank and met inclusion criteria. Of these, 10,572 (35.9%) were transferred to a higher level of care institution. Multivariable logistic regression after coarsened exact matching demonstrated an association of uninsured patients with an increased possibility of transfer (odds ratio [OR] = 1.22; 95% confidence interval [CI], 1.05-1.42). On the contrary, there was no association of African Americans with transfers (OR = 1.27; 95% CI, 0.99-1.62). Those with Glasgow Coma Scale score above 8 (OR = 1.22; 95% CI, 1.08-1.39) or Injury Severity Score below 16 (OR = 1.33; 95% CI, 1.13-1.56) had a higher possibility of transfer. CONCLUSIONS: In TBI patients, lack of insurance was associated with an increased possibility of transfer to higher level of care institutions after evaluation in a level III or IV trauma center emergency department. Regardless of insurance status, this transfer pattern was also observed for African Americans, but only for those with milder injuries.

Prehospital helicopter transport and survival of patients with traumatic brain injury.

OBJECTIVE: To investigate the association of helicopter transport with survival of patients with traumatic brain injury (TBI), in comparison with ground emergency medical services (EMS). BACKGROUND: Helicopter utilization and its effect on the outcomes of TBI remain controversial. METHODS: We performed a retrospective cohort study involving patients with TBI who were registered in the National Trauma Data Bank between 2009 and 2011. Regression techniques with propensity score matching were used to investigate the association of helicopter transport with survival of patients with TBI, in comparison with ground EMS. RESULTS: During the study period, there were 209,529 patients with TBI who were registered in the National Trauma Data Bank and met the inclusion criteria. Of these patients, 35,334 were transported via helicopters and 174,195 via ground EMS. For patients transported to level I trauma centers, 2797 deaths (12%) were recorded after helicopter transport and 8161 (7.8%) after ground EMS. Multivariable logistic regression analysis demonstrated an association of helicopter transport with increased survival [OR (odds ratio), 1.95; 95% confidence interval (CI), 1.81-2.10; absolute risk reduction (ARR), 6.37%]. This persisted after propensity score matching (OR, 1.88; 95% CI, 1.74-2.03; ARR, 5.93%). For patients transported to level II trauma centers, 1282 deaths (10.6%) were recorded after helicopter transport and 5097 (7.3%) after ground EMS. Multivariable logistic regression analysis demonstrated an association of helicopter transport with increased survival (OR, 1.81; 95% CI, 1.64-2.00; ARR 5.17%). This again persisted after propensity score matching (OR, 1.73; 95% CI, 1.55-1.94; ARR, 4.69). CONCLUSIONS: Helicopter transport of patients with TBI to level I and II trauma centers was associated with improved survival, in comparison with ground EMS.

The subventricular zone in the immature piglet brain: anatomy and exodus of neuroblasts into white matter after traumatic brain injury.

Stimulation of postnatal neurogenesis in the subventricular zone (SVZ) and robust migration of neuroblasts to the lesion site in response to traumatic brain injury (TBI) is well established in rodent species; however, it is not yet known whether postnatal neurogenesis plays a role in repair after TBI in gyrencephalic species. Here we describe the anatomy of the SVZ in the piglet for the first time and initiate an investigation into the effect of TBI on the SVZ architecture and the number of neuroblasts in the white matter. Among all ages of immaturity examined the SVZ contained a dense mesh network of neurogenic precursor cells (doublecortin+) positioned directly adjacent to the ependymal cells (ventricular SVZ, Vsvz) and neuroblasts organized into chains that were distinct from the Vsvz (abventricular SVZ, Asvz). Though the architecture of the SVZ was similar among ages, the areas of Vsvz and Asvz neuroblast chains declined with age. At postnatal day (PND) 14 the white matter tracts have a tremendous number of individual neuroblasts. In our scaled cortical impact model, lesion size increased with age. Similarly, the response of the SVZ to injury was also age dependent. The younger age groups that sustained the proportionately smallest lesions had the largest SVZ areas, which further increased in response to injury. In piglets that were injured at 4 months of age and had the largest lesions, the SVZ did not increase in response to injury. Similar to humans, swine have abundant gyri and gyral white matter, providing a unique platform to study neuroblasts potentially migrating from the SVZ to the lesioned cortex along these white matter tracts. In piglets injured at PND 7, TBI did not increase the total number of neuroblasts in the white matter compared to uninjured piglets, but redistribution occurred with a greater number of neuroblasts in the white matter of the hemisphere ipsilateral to the injury compared to the contralateral hemisphere. At 7 days after injury, less than 1% of neuroblasts in the white matter were born in the 2 days following injury. These data show that the SVZ in the piglet shares many anatomical similarities with the SVZ in the human infant, and that TBI had only modest effects on the SVZ and the number of neuroblasts in the white matter. Piglets at an equivalent developmental stage to human infants were equipped with the largest SVZ and a tremendous number of neuroblasts in the white matter, which may be sufficient in lesion repair without the dramatic stimulation of neurogenic machinery. It has yet to be determined whether neurogenesis and migrating neuroblasts play a role in repair after TBI and/or whether an alteration of normal migration during active postnatal population of brain regions is beneficial in species with gyrencephalic brains.

Drivers of hospitalization cost after craniotomy for tumor resection: creation and validation of a predictive model.

BACKGROUND: The economic sustainability of all areas of medicine is under scrutiny. Limited data exist on the drivers of cost after a craniotomy for tumor resection (CTR). The objective of the present study was to develop and validate a predictive model of hospitalization cost after CTR. METHODS: We performed a retrospective study involving CTR patients who were registered in the Nationwide Inpatient Sample (NIS) database from 2005-2010. This cohort underwent 1:1 randomization to create derivation and validation subsamples. Regression techniques were used for the creation of a parsimonious predictive model. RESULTS: Of the 36,433 patients undergoing CTR, 14638 (40.2%) underwent craniotomies for primary malignant, 9574 (26.3%) for metastatic, and 11414 (31.3%) for benign tumors. The median hospitalization cost was $24,504 (Interquartile Range (IQR), $4,265-$44,743). Common drivers of cost identified in the multivariate analyses included: length of stay, number of procedures, hospital size and region, and patient income. The models were validated in independent cohorts and demonstrated final R2 very similar to the initial models. The predicted and observed values in the validation cohort demonstrated good correlation. CONCLUSIONS: This national study identified significant drivers of hospitalization cost after CTR. The presented model can be utilized as an adjunct in the cost containment debate and the creation of data-driven policies.

Renaissance of laser interstitial thermal ablation.

Laser interstitial thermal therapy (LITT) is a minimally invasive technique for treating intracranial tumors, originally introduced in 1983. Its use in neurosurgical procedures was historically limited by early technical difficulties related to the monitoring and control of the extent of thermal damage. The development of magnetic resonance thermography and its application to LITT have allowed for real-time thermal imaging and feedback control during laser energy delivery, allowing for precise and accurate provision of tissue hyperthermia. Improvements in laser probe design, surgical stereotactic targeting hardware, and computer monitoring software have accelerated acceptance and clinical utilization of LITT as a neurosurgical treatment alternative. Current commercially available LITT systems have been used for the treatment of neurosurgical soft-tissue lesions, including difficult to access brain tumors, malignant gliomas, and radiosurgery-resistant metastases, as well as for the ablation of such lesions as epileptogenic foci and radiation necrosis. In this review, the authors aim to critically analyze the literature to describe the advent of LITT as a neurosurgical, laser excision tool, including its development, use, indications, and efficacy as it relates to neurosurgical applications.

Association of risk factors with unfavorable outcomes after resection of adult benign intradural spine tumors and the effect of hospital volume on outcomes: an analysis of 18, 297 patients across 774 US hospitals using the National Inpatient Sample (2002-2011).

OBJECT Because of the limited data available regarding the associations between risk factors and the effect of hospital case volume on outcomes after resection of intradural spine tumors, the authors attempted to identify these associations by using a large population-based database. METHODS Using the National Inpatient Sample database, the authors performed a retrospective cohort study that involved patients who underwent surgery for an intradural spinal tumor between 2002 and 2011. Using national estimates, they identified associations of patient demographics, medical comorbidities, and hospital characteristics with inpatient postoperative outcomes. In addition, the effect of hospital volume on unfavorable outcomes was investigated. Hospitals that performed fewer than 14 resections in adult patients with an intradural spine tumor between 2002 and 2011 were labeled as low-volume centers, whereas those that performed 14 or more operations in that period were classified as high-volume centers (HVCs). These cutoffs were based on the median number of resections performed by hospitals registered in the National Inpatient Sample during the study period. RESULTS Overall, 18,297 patients across 774 hospitals in the United States underwent surgery for an intradural spine tumor. The mean age of the cohort was 56.53 ± 16.28 years, and 63% were female. The inpatient postoperative risks included mortality (0.3%), discharge to rehabilitation (28.8%), prolonged length of stay (> 75th percentile) (20.0%), high-end hospital charges (> 75th percentile) (24.9%), wound complications (1.2%), cardiac complications (0.6%), deep vein thrombosis (1.4%), pulmonary embolism (2.1%), and neurological complications, including durai tears (2.4%). Undergoing surgery at an HVC was significantly associated with a decreased chance of inpatient mortality (OR 0.39; 95% CI 0.16-0.98), unfavorable discharge (OR 0.86; 95% CI 0.76-0.98), prolonged length of stay (OR 0.69; 95% CI 0.62-0.77), high-end hospital charges (OR 0.67; 95% CI 0.60-0.74), neurological complications (OR 0.34; 95% CI 0.26-0.44), deep vein thrombosis (OR 0.65; 95% CI 0.45-0.94), wound complications (OR 0.59; 95% CI 0.41-0.86), and gastrointestinal complications (OR 0.65; 95% CI 0.46-0.92). CONCLUSIONS The results of this study provide individualized estimates of the risks of postoperative complications based on patient demographics and comorbidities and hospital characteristics and shows a decreased risk for most unfavorable outcomes for those who underwent surgery at an HVC. These findings could be used as a tool for risk stratification, directing presurgical evaluation, assisting with surgical decision making, and strengthening referral systems for complex cases.

Predictors of unfavorable outcomes following deep brain stimulation for movement disorders and the effect of hospital case volume on outcomes: an analysis of 33, 642 patients across 234 US hospitals using the National (Nationwide) Inpatient Sample from 2002 to 2011.

OBJECT: With limited data available on association of risk factors and effect of hospital case volume on outcomes following deep brain stimulation (DBS), the authors attempted to identify these associations using a large population-based database. METHODS: The authors performed a retrospective cohort study involving patients who underwent DBS for 3 primary movement disorders: Parkinson's disease, essential tremor, and dystonia from 2002 to 2011 using the National (Nationwide) Inpatient Sample (NIS) database. Using national estimates, the authors identified associations of patient demographics, clinical characteristics, and hospital characteristics on short-term postoperative outcomes following DBS. Additionally, effect of hospital volume on unfavorable outcomes was investigated. RESULTS: Overall, 33, 642 patients underwent DBS for 3 primary movement disorders across 234 hospitals in the US. The mean age of the cohort was 63.42 ± 11.31 years and 36% of patients were female. The inpatients' postoperative risks were 5.9% for unfavorable discharge, 10.2% for prolonged length of stay, 14.6% for high-end hospital charges, 0.5% for wound complications, 0.4% for cardiac complications, 1.8% for venous thromboembolism, and 5.5% for neurological complications, including those arising from an implanted nervous system device. Compared with low-volume centers, odds of having an unfavorable discharge, prolonged LOS, high-end hospital charges, wound, and cardiac complications were significantly lower in the high-volume and medium-volume centers. CONCLUSIONS: The authors' study provides individualized estimates of the risks of postoperative complications based on patient demographics and comorbidities and hospital characteristics, which could potentially be used as an adjunct for risk stratification for patients undergoing DBS.

Woodrow Wilson's hidden stroke of 1919: the impact of patient-physician confidentiality on United States foreign policy.

World War I catapulted the United States from traditional isolationism to international involvement in a major European conflict. Woodrow Wilson envisaged a permanent American imprint on democracy in world affairs through participation in the League of Nations. Amid these defining events, Wilson suffered a major ischemic stroke on October 2, 1919, which left him incapacitated. What was probably his fourth and most devastating stroke was diagnosed and treated by his friend and personal physician, Admiral Cary Grayson. Grayson, who had tremendous personal and professional loyalty to Wilson, kept the severity of the stroke hidden from Congress, the American people, and even the president himself. During a cabinet briefing, Grayson formally refused to sign a document of disability and was reluctant to address the subject of presidential succession. Wilson was essentially incapacitated and hemiplegic, yet he remained an active president and all messages were relayed directly through his wife, Edith. Patient-physician confidentiality superseded national security amid the backdrop of friendship and political power on the eve of a pivotal juncture in the history of American foreign policy. It was in part because of the absence of Woodrow Wilson's vocal and unwavering support that the United States did not join the League of Nations and distanced itself from the international stage. The League of Nations would later prove powerless without American support and was unable to thwart the rise and advance of Adolf Hitler. Only after World War II did the United States assume its global leadership role and realize Wilson's visionary, yet contentious, groundwork for a Pax Americana. The authors describe Woodrow Wilson's stroke, the historical implications of his health decline, and its impact on United States foreign policy.

National trends of incidence, treatment, and hospital charges of isolated C-2 fractures in three different age groups.

OBJECT: Incidence of C-2 fracture is increasing in elderly patients. Patient age also influences decision making in the management of these fractures. There are very limited data on the national trends of incidence, treatment interventions, and resource utilization in patients in different age groups with isolated C-2 fractures. The aim of this study is to investigate the incidence, treatment, complications, length of stay, and hospital charges of isolated C-2 fracture in patients in 3 different age groups by using the Nationwide Inpatient Sample (NIS) database. METHODS: The data were obtained from NIS from 2002 to 2011. Data on patients with closed fractures of C-2 without spinal cord injury were extracted using ICD-9-CM diagnosis code 805.02. Patients with isolated C-2 fractures were identified by excluding patients with other associated injuries. The cohort was divided into 3 age groups: < 65 years, 65-80 years, and > 80 years. Incidence, treatment characteristics, inpatient/postoperative complications, and hospital charges (mean and total annual charges) were compared between the 3 age groups. RESULTS: A total of 10,336 patients with isolated C-2 fractures were identified. The majority of the patients were in the very elderly age group (> 80 years; 42.3%) followed by 29.7% in the 65- to 80-year age group and 28% in < 65-year age group. From 2002 to 2011, the incidence of hospitalization significantly increased in the 65- to 80-year and > 80-year age groups (p < 0.001). However, the incidence did not change substantially in the < 65-year age group (p = 0.287). Overall, 21% of the patients were treated surgically, and 12.2% of the patients underwent nonoperative interventions (halo and spinal traction). The rate of nonoperative interventions significantly decreased over time in all age groups (p < 0.001). Regardless of treatment given, patients in older age groups had a greater risk of inpatient/postoperative complications, nonroutine discharges, and longer hospitalization. The mean hospital charges were significantly higher in older age groups (p < 0.001). CONCLUSIONS: The incidence of hospitalization for isolated C-2 fractures is progressively increasing in older age groups. Simultaneously, there has been a steadily decreasing trend in the preference for nonoperative interventions. Due to more complicated hospital stay, longer hospitalizations, and higher rates of nonroutine discharges, the patients in older age groups seem to have a higher propensity for greater health care resource utilization.

The association of regional intensity of neurosurgical care with spinal fusion surgery in the USA.

PURPOSE: There is wide regional variability in the volume of procedures performed for similar surgical patients throughout the USA. The purpose of this study was to investigate the association of spinal fusion operations with several socioeconomic factors. METHODS: We performed a retrospective cohort study involving patients who underwent any neurosurgical procedure from 2005 to 2010 and were registered in National Inpatient Sample (NIS). A sub-cohort of patients undergoing spinal operations was also created. Regression techniques were used to investigate the association of the average intensity of neurosurgical care (defined as the average number of neurosurgical procedures per capita) with the average rate of fusions. RESULTS: In the study period, there were 707,951 patients undergoing spinal procedures, who were registered in NIS. There were significant disparities in the fusion rate among different states (ANOVA, P < 0.0001), which ranged from 0.41 in Maine, where non-fusion surgeries were very predominant, to 0.62 in Virginia, where fusion was the main treatment modality used. In a multivariate analysis, the intensity of neurosurgical care was associated with an increased fusion rate. A similar effect was observed for coverage by private insurance, higher income, urban hospitals, large hospital size, African American patients, and patients with less comorbidities. Hospital location in the northeast was associated with a lower rate in comparison to the midwest, and south. Coverage by Medicaid was associated with lower fusion rate. CONCLUSIONS: We observed significant disparities in the integration of fusion operations in spine surgery practices in the USA. Increased intensity of neurosurgical care was associated with a higher fusion rate.

Stereotactic radiosurgery of intracranial arteriovenous malformations and the use of the K index in determining treatment dose.

OBJECT: The appropriate dose during stereotactic radiosurgery (SRS) of cerebral arteriovenous malformations (AVMs) remains a matter of debate. In the present study, the authors retrospectively evaluated the association of using a prescribed dose calculated utilizing the K index with the obliteration rate of cerebral AVMs after SRS. METHODS: The authors performed a retrospective analysis of the Cleveland Clinic SRS database. All patients undergoing Gamma Knife radiosurgery for cerebral AVMs from 1997 to 2010 were selected. Regression techniques and Kaplan-Meier analyses were used to investigate the effect of divergence from the optimal K index dose on the rate of AVM obliteration. RESULTS: In the study period 152 patients (mean age 43.6 years; 53.9% of treatments were performed in females) underwent 165 Gamma Knife radiosurgery treatments for AVMs. In a univariate analysis Spetzler-Martin grade (OR 0.63 [95% CI 0.42-0.93]), higher AVM score (OR 0.43 [95% CI 0.27-0.70]), larger AVM volume (OR 0.88 [95% CI 0.82-0.94]), and higher maximum diameter (OR 0.56 [95% CI 0.41-0.77]) were associated with a lower rate of AVM obliteration. Higher margin dose (OR 1.16 [95% CI 1.08-1.24]) and higher maximum dose (OR 1.08 [95% CI 1.04-1.13]) were associated with a higher obliteration rate. To further examine the effect of prescribed dose divergence from the calculated K index dose, cases were classified to groups depending on the AVM volume and dose variance from the ideal K index dose. Contingency tables and Kaplan-Meier curves were then created, and no significant differences in rates of obliteration were noted among the different groups. CONCLUSIONS: Gamma Knife radiosurgery for cerebral AVMs remains an effective and safe treatment modality. Smaller AVMs may receive doses less than the calculated K index dose without an apparent effect on obliteration rates.

Spinal cord stimulators: socioeconomic disparities in four US states.

OBJECTIVES: Spinal cord stimulators (SCS) are increasingly placed in the United States in both the inpatient and outpatient setting. Although these interventions appear to be safe, the characteristics of the patients selected for ambulatory procedures have not been investigated. MATERIALS AND METHODS: We performed a retrospective cohort study involving 4843 patients who underwent outpatient and 4197 who underwent inpatient SCS placements and were registered in State Ambulatory Surgery Databases and State Inpatient Databases, respectively, for New York, California, Florida, and North Carolina from 2005 to 2008. RESULTS: In a multivariate analysis, male gender (odds ratio (OR) 1.22, 95% confidence interval (CI), 1.12, 1.33), high volume hospitals (OR 2.16, 95% CI, 1.94, 2.41), and Caucasian race (OR 1.25, 95% CI, 1.10, 1.41) were significantly associated with outpatient procedures. Higher Charlson Comorbidity Index (OR 0.36, 95% CI, 0.24, 0.54) and Medicare/Medicaid insurance (OR 0.75, 95% CI, 0.67, 0.83) were associated with a decreased chance of outpatient procedures. The rate of 30-day postoperative readmissions was higher among inpatients. Institutional charges were significantly lower for outpatient lumbar discectomies. The median total charge for inpatient hospitalization after SCS placement was $60,624 as compared with $22,288 for the outpatient setting (p < 0.0001). CONCLUSIONS: Access to ambulatory SCS placement appears to be more common for Caucasians, male patients, with private insurance, and fewer comorbidities, in the setting of higher volume hospitals. Further investigation is needed in the direction of mapping these disparities for appropriate resource utilization.