Long-term disease-free survival following comprehensive involved site radiotherapy for oligometastases.

Introduction: Despite recent advances in drug development, durable complete remissions with systemic therapy alone for metastatic cancers remain infrequent. With the development of advanced radiation technologies capable of selectively sparing normal tissues, patients with oligometastases are often amenable to comprehensive involved site radiotherapy with curative intent. This study reports the long-term outcomes and patterns of failure for patients treated with total metastatic ablation often in combination with systemic therapy. Materials and methods: Consecutive adult patients with oligometastases from solid tumor malignancy treated by a single high volume radiation oncologist between 2014 and 2021 were retrospectively analyzed. Oligometastases were defined as 5 or fewer metastatic lesions where all sites of active disease are amenable to local treatment. Comprehensive involved site radiotherapy consisted of stereotactic radiotherapy to a median dose of 27 Gy in 3 fractions and intensity modulated radiation therapy to a median dose of 50 Gy in 15 fractions. This study analyzed overall survival, progression-free survival, patterns of failure and toxicity. Results: A total of 130 patients with 209 treated distant metastases were treated with a median follow-up of 36 months. The 4-year overall survival, progression-free survival, local control and distant control was 41%, 23%, 86% and 29%. Patterns of failure include 23% alive and free of disease (NED), 52% distant failure only, 9% NED but death from comorbid illness, 7% both local and distant failure, 4% NED but lost to follow-up, 4% referred to hospice before restaging, 1% local only failure, 1% alive with second primary cancer. Late grade 3+ toxicities occurred in 4% of patients, most commonly radionecrosis. Conclusion: Involved site radiotherapy to all areas of known disease can safely achieve durable complete remissions in patients with oligometastases treated in the real world setting. Distant failures account for the majority of treatment failures and isolated local failures are exceedingly uncommon. Oligometastases represents a promising setting to investigate novel therapeutics targeting minimal residual disease.

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.

Characteristics of a COVID-19 Cohort With Large Vessel Occlusion: A Multicenter International Study.

BACKGROUND: The mechanisms and outcomes in coronavirus disease (COVID-19)-associated stroke are unique from those of non-COVID-19 stroke. OBJECTIVE: To describe the efficacy and outcomes of acute revascularization of large vessel occlusion (LVO) in the setting of COVID-19 in an international cohort. METHODS: We conducted an international multicenter retrospective study of consecutively admitted patients with COVID-19 with concomitant acute LVO across 50 comprehensive stroke centers. Our control group constituted historical controls of patients presenting with LVO and receiving a mechanical thrombectomy between January 2018 and December 2020. RESULTS: The total cohort was 575 patients with acute LVO; 194 patients had COVID-19 while 381 patients did not. Patients in the COVID-19 group were younger (62.5 vs 71.2; P < .001) and lacked vascular risk factors (49, 25.3% vs 54, 14.2%; P = .001). Modified thrombolysis in cerebral infarction 3 revascularization was less common in the COVID-19 group (74, 39.2% vs 252, 67.2%; P < .001). Poor functional outcome at discharge (defined as modified Ranklin Scale 3-6) was more common in the COVID-19 group (150, 79.8% vs 132, 66.7%; P = .004). COVID-19 was independently associated with a lower likelihood of achieving modified thrombolysis in cerebral infarction 3 (odds ratio [OR]: 0.4, 95% CI: 0.2-0.7; P < .001) and unfavorable outcomes (OR: 2.5, 95% CI: 1.4-4.5; P = .002). CONCLUSION: COVID-19 was an independent predictor of incomplete revascularization and poor outcomes in patients with stroke due to LVO. Patients with COVID-19 with LVO were younger, had fewer cerebrovascular risk factors, and suffered from higher morbidity/mortality rates.

Association of radiation dose intensity with overall survival in patients with distant metastases.

BACKGROUND: Patients with metastatic cancer referred to radiation oncology have diverse prognoses and there is significant interest in personalizing treatment. We hypothesized that patients selected for higher biologically equivalent doses have improved overall survival. METHODS: The study population consists of 355 consecutive adult patients with distant metastases treated by a single radiation oncologist from 2014 to 2018. The validated NEAT model was used to prospectively stratify patients into four distinct cohorts. Radiation dose intensity was standardized using the equivalent dose in 2 Gy fractions (EQD2) model with an α/ß of 10. Radiation dose intensity on survival was assessed via Cox regression models and propensity score match pairing with Kaplan-Meier analysis. RESULTS: The median survival was 9.3 months and the median follow-up for surviving patients was 18.3 months. The NEAT model cohorts indicated median survivals of 29.5, 11.8, 4.9, and 1.8 months. Patients receiving an EQD2 of ≥40 Gy had a median survival of 16.0 months versus 3.8 months for patients receiving an EQD2 of <40 Gy (p < 0.001). On multivariable analysis, performance status, primary tumor site, radiation dose intensity, albumin, liver metastases, and number of active tumors were all independent predictors of survival (p < 0.05 for all). Propensity score matching was performed for performance status, albumin, number of active tumors, primary tumor site, and liver metastasis, finding higher EQD2 to remain significantly associated with improved survival within the matched cohort (p = 0.004). CONCLUSION: Higher radiation dose intensity was used in patients with better prognosis and was associated with improved survival for patients with metastatic disease.

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.

Cerebral ischemic and hemorrhagic complications of coronavirus disease 2019.

BACKGROUND: The coronavirus disease 2019 is associated with neurological manifestations including stroke. OBJECTIVES: We present a case series of coronavirus disease 2019 patients from two institutions with acute cerebrovascular pathologies. In addition, we present a pooled analysis of published data on large vessel occlusion in the setting of coronavirus disease 2019 and a concise summary of the pathophysiology of acute cerebrovascular disease in the setting of coronavirus disease 2019. METHODS: A retrospective study across two institutions was conducted between 20 March 2020 and 20 May 2020, for patients developing acute cerebrovascular disease and diagnosed with coronavirus disease 2019. We performed a literature review using the PubMed search engine. RESULTS: The total sample size was 22 patients. The mean age was 59.5 years, and 12 patients were female. The cerebrovascular pathologies were 17 cases of acute ischemic stroke, 3 cases of aneurysm rupture, and 2 cases of sinus thrombosis. Of the stroke and sinus thrombosis patients, the mean National Institute of Health Stroke Scale was 13.8 ± 8.0, and 16 (84.2%) patients underwent a mechanical thrombectomy procedure. A favorable thrombolysis in cerebral infarction score was achieved in all patients. Of the 16 patients that underwent a mechanical thrombectomy, the mortality incidence was five (31.3%). Of all patients (22), three (13.6%) patients developed hemorrhagic conversion requiring decompressive surgery. Eleven (50%) patients had a poor functional status (modified Rankin Score 3-6) at discharge, and the total mortality incidence was eight (36.4%). CONCLUSIONS: Despite timely intervention and favorable reperfusion, the mortality rate in coronavirus disease 2019 patients with large vessel occlusion was high in our series and in the pooled analysis. Notable features were younger age group, involvement of both the arterial and venous vasculature, multivessel involvement, and complicated procedures due to the clot consistency and burden.

Predictors of ventriculostomy infection in a large single-center cohort.

OBJECTIVE: External ventricular drain (EVD) placement is a common neurosurgical procedure. While this procedure is simple and effective, infection is a major limiting factor. Factors predictive of infection reported in the literature are not conclusive. The aim of this retrospective, single-center large series was to assess the rate and independent predictors of ventriculostomy-associated infection (VAI). METHODS: The authors performed a retrospective chart review of consecutive patients who underwent EVD placement between January 2012 and January 2018. RESULTS: A total of 389 patients were included in the study. The infection rate was 3.1% (n = 12). Variables that were significantly associated with VAI were EVD replacement (OR 10, p = 0.001), bilateral EVDs (OR 9.2, p = 0.009), duration of EVD placement (OR 1.1, p = 0.011), increased CSF output/day (OR 1.0, p = 0.001), CSF leak (OR 12.9, p = 0.001), and increased length of hospital stay (OR 1.1, p = 0.002). Using multivariate logistic regression, independent predictors of VAI were female sex (OR 7.1, 95% CI 1.1-47.4; p = 0.043), EVD replacement (OR 8.5, 95% CI 1.44-50.72; p = 0.027), increased CSF output/day (OR 1.01, 95% CI 1.0-1.02; p = 0.023), and CSF leak (OR 15.1, 95% CI 2.6-87.1; p = 0.003). CONCLUSIONS: The rate of VAI was 3.1%. Routine CSF collection (every other day or every 3 days) and CSF collection when needed were not associated with VAI. The authors recommend CSF collection when clinically needed rather than routinely.

Pipeline for Distal Cerebral Circulation Aneurysms.

BACKGROUND: Pipeline embolization device (PED; Medtronic, Dublin, Ireland) utilization is not limited to the treatment of giant wide-necked aneurysms. It has been expanded to handle small blisters, fusiforms, and dissecting intracranial aneurysms. OBJECTIVE: To report the use of the PED in various off-label distal cerebral circulation (DCC) arteries with a follow-up to assess clinical outcomes. METHODS: Between 2011 and 2016, of 437 consecutive patients, 23 patients with aneurysms located in DCCs were treated with PED. Data on patient presentation, aneurysm characteristics, procedural outcomes, postoperative course, and aneurysm occlusion were gathered. To control confounding, we used multivariable logistic regression and propensity score conditioning. RESULTS: A total of 437 patients (mean age 52.12 years; 62 women [14.2%]) underwent treatment with PED in our institution. Twenty-three of 437 (5.2%) received a pipeline in a distal artery: 11/23 middle cerebral artery, 6/23 posterior cerebral artery, 3/23 anterior cerebral artery (A1/A2, pericallosal artery), and 3/23 posterior inferior cerebellar artery. Twenty percent of the aneurysms were treated in the past, 10% had previously ruptured, and 5.9% ruptured at presentation to our hospital. The mean aneurysm size was 9.0 ± 6 mm. The mean follow-up was 12 mo (SD = 12.5). In multivariable logistic regression, no associations were found between PED deployment in DCCs and aneurysm occlusion or thromboembolic complications. PED use in DCC was associated with a good clinical outcome. Twenty-two people of 23 (95%) had a good clinical outcome in the latest follow-up. CONCLUSION: Treatment of DCC aneurysms with PED is technically challenging mainly because of the small caliber and tortuosity of the parent arteries. The results of this study further support the safety of flow diverters in the treatment of various distal aneurysms.

Emergency medical services for acute ischemic stroke: Hub-and-spoke model versus exclusive care in comprehensive centers.

BACKGROUND: The emergent disposition of acute stroke patients remains an issue of debate. We investigated whether a hub-and-spoke model was associated with worse stroke outcomes when compared to care exclusively in comprehensive centers. METHODS: We performed a cohort study of all acute ischemic stroke patients who were hospitalized in endovascular-capable facilities, and were registered in the New York Statewide Planning and Research Cooperative System (SPARCS) database from 2009 to 2015. We examined the association of transfer status (transfer to endovascular capable hospitals versus initial treatment in these facilities) with inpatient case-fatality, discharge to a facility, and length of stay (LOS). An instrumental variable analysis was used to control for unmeasured confounding and simulate a randomized trial. RESULTS: During the study period, 128,122 acute stroke patients met inclusion criteria. Instrumental variable analysis demonstrated that patients transferred to endovascular-capable hospitals did not have higher case-fatality (Adjusted difference, 4.4%; 95% CI, -0.1% to 9.0%), rate discharge to a facility (Adjusted difference, -2.3%; 95% CI, -5.2% to 0.6%), or longer LOS (Adjusted difference, 4.2; 95% CI, -2.2 to 10.1) in comparison to patients presenting for initial treatment in these facilities. The same associations were present when restricting the cohort to patients receiving intravenous tissue plasminogen (IV-tPA) and to patients receiving mechanical thrombectomy. CONCLUSIONS: Using a comprehensive all-payer cohort of acute ischemic stroke patients in New York State we demonstrated that patients treated in a hub-and-spoke model were not associated with worse outcomes than patients receiving care exclusively in comprehensive institutions. This needs to be taken into consideration when considering acute emergency services in this setting.

Surgical outcomes for patients diagnosed with dementia: A coarsened exact matching study.

BACKGROUND: An increasing number of elderly patients with dementia are undergoing surgical operations. Little is known about the differential impact of dementia on surgical outcomes. We investigated whether demented patients undergoing surgical operations have worse outcomes than their non-demented counterparts. METHODS: We performed a cohort study of all patients undergoing a series of surgical operations who were registered in the New York Statewide Planning and Research Cooperative System (SPARCS) database from 2009 to 2013. We examined the association of dementia with inpatient case-fatality, discharge to a facility, and length of stay (LOS). Coarsened exact matching was used to balance comorbidities among the comparison groups, and mixed effect methods were used to control for clustering at the hospital level. RESULTS: During the study period, 342,075 patients underwent surgical operations that met the inclusion criteria. Multivariable logistic regression models, after coarsened exact matching, demonstrated that demented patients were not associated with higher case-fatality (OR, 0.43; 95% CI, 0.13-1.36), but were associated with higher rates of discharge to a facility (OR, 1.71; 95% CI, 1.26-2.31) and longer LOS (Adjusted difference, 31%; 95% CI, 26%-36%). These persisted in pre-specified subgroups stratified on particular operations. CONCLUSIONS: Using a comprehensive all-payer cohort of surgical patients in New York State we identified an association of dementia with increased rate of discharge to rehabilitation and longer LOS. No difference was identified in the case fatality of the two groups. Policy makers, payers, and physicians should take these findings into account when designing new policies, and when counseling patients.

Effect of treatment period on outcomes after stereotactic radiosurgery for brain arteriovenous malformations: an international multicenter study.

OBJECTIVEThe role of and technique for stereotactic radiosurgery (SRS) in the management of arteriovenous malformations (AVMs) have evolved over the past four decades. The aim of this multicenter, retrospective cohort study was to compare the SRS outcomes of AVMs treated during different time periods.METHODSThe authors selected patients with AVMs who underwent single-session SRS at 8 different centers from 1988 to 2014 with follow-up ≥ 6 months. The SRS eras were categorized as early (1988-2000) or modern (2001-2014). Statistical analyses were performed to compare the baseline characteristics and outcomes of the early versus modern SRS eras. Favorable outcome was defined as AVM obliteration, no post-SRS hemorrhage, and no permanently symptomatic radiation-induced changes (RICs).RESULTSThe study cohort comprised 2248 patients with AVMs, including 1584 in the early and 664 in the modern SRS eras. AVMs in the early SRS era were significantly smaller (p < 0.001 for maximum diameter and volume), and they were treated with a significantly higher radiosurgical margin dose (p < 0.001). The obliteration rate was significantly higher in the early SRS era (65% vs 51%, p < 0.001), and earlier SRS treatment period was an independent predictor of obliteration in the multivariate analysis (p < 0.001). The rates of post-SRS hemorrhage and radiological, symptomatic, and permanent RICs were not significantly different between the two groups. Favorable outcome was achieved in a significantly higher proportion of patients in the early SRS era (61% vs 45%, p < 0.001), but the earlier SRS era was not statistically significant in the multivariate analysis (p = 0.470) with favorable outcome.CONCLUSIONSDespite considerable advances in SRS technology, refinement of AVM selection, and contemporary multimodality AVM treatment, the study failed to observe substantial improvements in SRS favorable outcomes or obliteration for patients with AVMs over time. Differences in baseline AVM characteristics and SRS treatment parameters may partially account for the significantly lower obliteration rates in the modern SRS era. However, improvements in patient selection and dose planning are necessary to optimize the utility of SRS in the contemporary management of AVMs.

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.

Association of Hospitalization for Neurosurgical Operations in Magnet Hospitals With Mortality and Length of Stay.

BACKGROUND: The association of Magnet hospital status with improved surgical outcomes remains an issue of debate. OBJECTIVE: To investigate whether hospitalization in a Magnet hospital is associated with improved outcomes for patients undergoing neurosurgical operations. METHODS: A cohort study was executed using all patients undergoing neurosurgical operations in New York registered in the Statewide Planning and Research Cooperative System database from 2009 to 2013. We examined the association of Magnet status hospitalization after neurosurgical operations with inpatient case fatality and length of stay (LOS). We employed an instrumental variable analysis to simulate a randomized trial. RESULTS: Overall, 190 787 patients underwent neurosurgical operations. Of these, 68 046 (35.7%) were hospitalized in Magnet hospitals, and 122 741 (64.3%) in non-Magnet institutions. Instrumental variable analysis demonstrated that hospitalization in Magnet hospitals was associated with decreased case fatality (adjusted difference, -0.8%; -95% confidence interval, -0.7% to -0.6%), and LOS (adjusted difference, -1.9; 95% confidence interval, -2.2 to -1.5) in comparison to non-Magnet hospitals. These associations were also observed in propensity score adjusted mixed effects models. These associations persisted in prespecified subgroups of patients undergoing spine surgery, craniotomy for tumor resection, or neurovascular interventions. CONCLUSION: We identified an association of Magnet hospitals with lower case fatality, and shorter LOS in a comprehensive New York State patient cohort undergoing neurosurgical procedures.

Stereotactic radiosurgery for Spetzler-Martin Grade IV and V arteriovenous malformations: an international multicenter study.

OBJECTIVE Due to the complexity of Spetzler-Martin (SM) Grade IV-V arteriovenous malformations (AVMs), the management of these lesions remains controversial. The aims of this multicenter, retrospective cohort study were to evaluate the outcomes after single-session stereotactic radiosurgery (SRS) for SM Grade IV-V AVMs and determine predictive factors. METHODS The authors retrospectively pooled data from 233 patients (mean age 33 years) with SM Grade IV (94.4%) or V AVMs (5.6%) treated with single-session SRS at 8 participating centers in the International Gamma Knife Research Foundation. Pre-SRS embolization was performed in 71 AVMs (30.5%). The mean nidus volume, SRS margin dose, and follow-up duration were 9.7 cm3, 17.3 Gy, and 84.5 months, respectively. Statistical analyses were performed to identify factors associated with post-SRS outcomes. RESULTS At a mean follow-up interval of 84.5 months, favorable outcome was defined as AVM obliteration, no post-SRS hemorrhage, and no permanently symptomatic radiation-induced changes (RIC) and was achieved in 26.2% of patients. The actuarial obliteration rates at 3, 7, 10, and 12 years were 15%, 34%, 37%, and 42%, respectively. The annual post-SRS hemorrhage rate was 3.0%. Symptomatic and permanent RIC occurred in 10.7% and 4% of the patients, respectively. Only larger AVM diameter (p = 0.04) was found to be an independent predictor of unfavorable outcome in the multivariate logistic regression analysis. The rate of favorable outcome was significantly lower for unruptured SM Grade IV-V AVMs compared with ruptured ones (p = 0.042). Prior embolization was a negative independent predictor of AVM obliteration (p = 0.024) and radiologically evident RIC (p = 0.05) in the respective multivariate analyses. CONCLUSIONS In this multi-institutional study, single-session SRS had limited efficacy in the management of SM Grade IV-V AVMs. Favorable outcome was only achieved in a minority of unruptured SM Grade IV-V AVMs, which supports less frequent utilization of SRS for the management of these lesions. A volume-staged SRS approach for large AVMs represents an alternative approach for high-grade AVMs, but it requires further investigation.

Phase I Trial of Radiosurgery Dose Escalation Plus Bevacizumab in Patients With Recurrent/Progressive Glioblastoma.

BACKGROUND: The effectiveness of stereotactic radiosurgery (SRS) for recurrent glioblastoma (rGBM) remains uncertain. SRS has been associated with a high risk of radionecrosis in gliomas. OBJECTIVE: To determine the safety of dose escalation of single-fraction radiosurgery for rGBM in the setting of bevacizumab therapy. METHODS: We conducted a prospective trial to determine the safety and synergistic benefit of higher doses of SRS administered with bevacizumab for rGBM. A single dose of bevacizumab was given prior to SRS and continued until progression. Dose-limiting toxicity was evaluated in successive cohorts of 3 patients. RESULTS: Seven males and 2 females entered the study. The maximum linear diameter of the enhancing tumor was 2.58 cm (2.04-3.09). Prescription dose was escalated from 18 to 22 Gy. The radiosurgery target was chosen before the first dose of bevacizumab, about 1 wk prior to SRS treatment. Pre-SRS bevacizumab treatment was associated with a reduction of the mean volume of the enhancing lesion from 4.7 to 2.86 cm3 on the day of SRS (P = .103). No patient developed an acute side effect related to SRS treatment. The combination of SRS and bevacizumab resulted in a partial response in 3 patients and stable disease in 6 patients. Median progression-free and overall survival were 7.5 and 13 mo, respectively. CONCLUSION: A single dose of bevacizumab prior to SRS permitted safe prescription dose escalation up to 22 Gy for rGBM. Further evaluation of the efficacy of SRS for rGBM should be performed in the setting of bevacizumab treatment.

Association of Hospital Teaching Status with Neurosurgical Outcomes: An Instrumental Variable Analysis.

BACKGROUND: The interpretation of the results of prior studies on the association of hospital teaching status with surgical outcomes is limited by selection bias. We investigated whether undergoing surgical operations in teaching hospitals is associated with improved outcomes. METHODS: We performed a cohort study of all patients undergoing spine and cranial operations who were registered in the New York Statewide Planning and Research Cooperative System database from 2009 to 2013. We examined the association of teaching status (defined as academic affiliation for the primary analysis) with inpatient case fatality, discharge to a facility, and length of stay (LOS). An instrumental variable analysis was used to control for unmeasured confounding and to simulate the effect of a randomized trial. RESULTS: During the study period, 186,483 patients underwent surgical operations that met the inclusion criteria. Instrumental variable analysis demonstrated that hospitalization in teaching hospitals was associated with higher rates of case fatality (adjusted difference, 25%; 95% confidence interval [CI], 4%-46%), discharge to a facility (adjusted difference, 5.7%; 95% CI, 4.5%-7.0%), and longer LOS (adjusted difference, 31.4%; 95% CI, 16.0%-46.1%) in comparison with nonteaching hospitals. The same associations were present in propensity score adjusted mixed effects models. These persisted in prespecified subgroups stratified on particular operations and for different definitions of teaching hospitals. CONCLUSIONS: Using a comprehensive all-payer cohort of surgical patients in New York State, we identified an association of treatment in teaching hospitals with increased case fatality, rate of discharge to rehabilitation, and longer LOS. Further research into the factors contributing to superior outcomes in nonteaching institutions is warranted.

Outcomes of Elective Cerebral Aneurysm Treatment Performed by Attending Neurosurgeons after Night Work.

BACKGROUND: The association between long work hours and outcomes among attending surgeons remains an issue of debate. OBJECTIVE: To investigate whether operating emergently the night before an elective case was associated with inferior outcomes among attending neurosurgeons. METHODS: We executed a cohort study with unruptured cerebral aneurysm patients, who underwent endovascular coiling or surgical clipping from 2009 to 2013 and were registered in the Statewide Planning and Research Cooperative System database. We investigated the association of treatment by surgeons performing emergency procedures the night before with outcomes of elective cerebral aneurysm treatment using an instrumental variable analysis. RESULTS: Overall, 4700 patients underwent treatment for unruptured cerebral aneurysms. There was no difference in inpatient mortality (adjusted difference, -0.7%; 95% confidence interval [CI], -1.4% to 0.02%), discharge to a facility (adjusted difference, -0.1%; 95% CI, -1.2% to 1.2%), or length of stay (adjusted difference, -0.58; 95% CI, -1.66 to 0.50) between patients undergoing elective cerebral aneurysm treatment by surgeons who performed emergency procedures the night before, and those who did not. CONCLUSION: Using a comprehensive patient cohort in New York State for elective treatment of unruptured cerebral aneurysms, we did not identify an association of treatment by surgeons performing emergency procedures the night before, with mortality, discharge to a facility, or length of stay. Our study had 80% power to detect differences in mortality (our primary outcome), as small as 4.1%. The results of the present study do not support the argument for regulation of attending work hours.

Access disparities to Magnet hospitals for patients undergoing neurosurgical operations.

BACKGROUND: Centers of excellence focusing on quality improvement have demonstrated superior outcomes for a variety of surgical interventions. We investigated the presence of access disparities to hospitals recognized by the Magnet Recognition Program of the American Nurses Credentialing Center (ANCC) for patients undergoing neurosurgical operations. METHODS: We performed a cohort study of all neurosurgery patients who were registered in the New York Statewide Planning and Research Cooperative System (SPARCS) database from 2009 to 2013. We examined the association of African-American race and lack of insurance with Magnet status hospitalization for neurosurgical procedures. A mixed effects propensity adjusted multivariable regression analysis was used to control for confounding. RESULTS: During the study period, 190,535 neurosurgical patients met the inclusion criteria. Using a multivariable logistic regression, we demonstrate that African-Americans had lower admission rates to Magnet institutions (OR 0.62; 95% CI, 0.58-0.67). This persisted in a mixed effects logistic regression model (OR 0.77; 95% CI, 0.70-0.83) to adjust for clustering at the patient county level, and a propensity score adjusted logistic regression model (OR 0.75; 95% CI, 0.69-0.82). Additionally, lack of insurance was associated with lower admission rates to Magnet institutions (OR 0.71; 95% CI, 0.68-0.73), in a multivariable logistic regression model. This persisted in a mixed effects logistic regression model (OR 0.72; 95% CI, 0.69-0.74), and a propensity score adjusted logistic regression model (OR 0.72; 95% CI, 0.69-0.75). CONCLUSIONS: Using a comprehensive all-payer cohort of neurosurgery patients in New York State we identified an association of African-American race and lack of insurance with lower rates of admission to Magnet hospitals.

Access disparities to Magnet hospitals for ischemic stroke patients.

Access disparities to centers of excellence can have detrimental consequences for population health. We investigated the presence of racial disparities in the access of stroke patients to hospitals recognized by the Magnet Recognition Program of the American Nurses Credentialing Center (ANCC). We performed a cohort study of all ischemic stroke patients who were registered in the New York Statewide Planning and Research Cooperative System (SPARCS) database from 2009 to 2013. We examined the association of African-American race with Magnet status hospitalization after ischemic stroke. A mixed effects propensity adjusted multivariable regression analysis was used to control for confounding. During the study period, 176,557 patients presented with ischemic stroke, and met the inclusion criteria. Overall, 4,624 (13.7%) African-Americans, and 27,468 (19.2%) non African-Americans with ischemic stroke were admitted to Magnet hospitals. Using a multivariable logistic regression, we demonstrate that African-Americans were associated with lower admission rates to Magnet institutions (OR 0.70; 95% CI, 0.68-0.73) (Table 2). This persisted in a mixed effects logistic regression model (OR 0.75; 95% CI, 0.71-0.78) to adjust for clustering at the county level, and a propensity score adjusted logistic regression model (OR 0.87; 95% CI, 0.83-0.90). Using a comprehensive all-payer cohort of ischemic stroke patients in New York State we identified an association of African-American race with lower rates of admission to Magnet hospitals.

Stereotactic Radiosurgery for Brainstem Arteriovenous Malformations: A Multicenter Study.

BACKGROUND: The management of brainstem arteriovenous malformations (bAVMs) is a formidable challenge. bAVMs harbor higher morbidity and mortality compared to other locations. OBJECTIVE: To review the outcomes following stereotactic radiosurgery (SRS) of bAVMs in a multicenter study. METHODS: Six medical centers contributed data from 205 patients through the International Gamma Knife Research Foundation. Median age was 32 yr (6-81). Median nidus volume was 1.4 mL (0.1-69 mL). Favorable outcome (FO) was defined as AVM obliteration and no post-treatment hemorrhage or permanent symptomatic radiation-induced complications. RESULTS: Overall obliteration was reported in 65.4% (n = 134) at a mean follow-up of 69 mo. Obliteration was angiographically proven in 53.2% (n = 109) and on MRA in 12.2% (n = 25). Actuarial rate of obliteration at 2, 3, 5, 7, and 10 yr after SRS was 24.5%, 43.3%, 62.3%, 73%, and 81.8% respectively. Patients treated with a margin dose >20 Gy were more likely to achieve obliteration (P = .001). Obliteration occurred earlier in patients who received a higher prescribed margin dose (P = .05) and maximum dose (P = .041). Post-SRS hemorrhage occurred in 8.8% (n = 18). Annual postgamma knife latency period hemorrhage was 1.5%. Radiation-induced complications were radiologically evident in 35.6% (n = 73), symptomatic in 14.6% (n = 30), and permanent in 14.6% (n = 30, which included long-tract signs and new cranial nerve deficits). FO was achieved in 64.4% (n = 132). Predictors of an FO were a higher Virginia radiosurgery AVM scale score (P = .003), prior hemorrhage (P = .045), and a lower prescribed maximum dose (P = .006). CONCLUSION: SRS for bAVMs results in obliteration and avoids permanent complications in the majority of patients.