Intracranial Meningioma Surgery: Value-Based Care Determinants in New York State, 1995-2015

OBJECTIVE

Intracranial meningiomas are the most commonly diagnosed brain tumor in the United States. With increasing incidence, efficient allocation of limited health care resources is a critical component of emerging value-based models of care. The purpose of this study was to evaluate the effect of patient and hospital variables on metrics of value-based care.

METHODS

The Statewide Planning and Research Cooperative System database was queried for records of patients undergoing intracranial meningioma surgery in New York State from 1995 to 2015. Multivariate logistic regression was used to investigate the effect of hospital volume and patient demographics on 30-day readmissions, 30-day mortality, prolonged length of stay (pLOS), and excess hospital charges.

RESULTS

Among the 14,239 patients included, 10,252 (72%) cases were performed at high-volume centers (HVC) (>75th percentile). HVC were associated with lower rates of readmissions, mortality, and pLOS, but higher hospital charges. In the multivariate analysis, HVC had reduced odds of pLOS (odds ratio, 0.56; P < 0.0001) and 30-day mortality (odds ratio, 0.39; P < 0.0001). Patient variables associated with adverse outcomes in the multivariate model included advanced age, male gender, higher Charlson Comorbidity Index, lower socioeconomic status (low income, Medicaid, and Medicare insurance), black race, and Hispanic ethnicity. These populations were more likely to undergo treatment at lower-volume centers.

CONCLUSIONS

This statewide population analysis of readmissions, mortality, length of stay, and hospital charges after intracranial meningioma surgery identified patient predictors of adverse outcomes. These determinants may be used by hospitals to develop improved systems of care in at-risk populations.

Brain metastasis from squamous cell carcinoma of the head and neck: a review of the literature in the genomic era

Squamous cell carcinoma of the head and neck (HNSCC) affects nearly 500,000 individuals globally each year. With the rise of human papillomavirus (HPV) in the general population, clinicians are seeing a concomitant rise in HPV-related HNSCC. Notably, a hallmark of HPV-related HNSCC is a predilection for unique biological and clinical features, which portend a tendency for hematogenous metastasis to distant locations, such as the brain. Despite the classic belief that HNSCC is restricted to local spread via passive lymphatic drainage, brain metastases (BMs) are a rare complication that occurs in less than 1% of all HNSCC cases. Time between initial diagnosis of HNSCC and BM development can vary considerably. Some patients experience more than a decade of disease-free survival, whereas others present with definitive neurological symptoms that precede primary tumor detection. The authors systematically review the current literature on HNSCC BMs and discuss the current understanding of the effect of HPV status on the risk of developing BMs in the modern genomic era.

The Stereotactic Intracerebral Hemorrhage Underwater Blood Aspiration (SCUBA) technique for minimally invasive endoscopic intracerebral hemorrhage evacuation

Background

Endoscopic intracerebral hemorrhage (ICH) evacuation techniques have gained interest as a potential therapeutic option. However, the instrumentation and techniques employed are still being refined to optimize hemostasis and evacuation efficiency.

Objective

We describe the application of a specific endoscopic technique in the treatment of ICH called the Stereotactic Intracerebral Hemorrhage Underwater Blood Aspiration (SCUBA) technique. It differs from previously described minimally invasive ICH interventions in that it combines two separate neuroendoscopic strategies in two phases, the first under dry-field conditions and the second using a wet-field strategy.

Methods

All patients who underwent endoscopic ICH evacuation with the SCUBA technique from December 2015 to September 2017 were included.

Results

The SCUBA technique was performed in 47 patients. The average evacuation percentage was 88.2% (SD 20.8). Active bleeding identified to derive from a specific source was observed in 23 (48.9%) cases. Active bleeding was addressed with irrigation alone in five cases (10.6%) and required electrocautery in 18 cases (38.3%). Intraoperative bleeding occurred in 3 patients (6.4%) and postoperative bleeding occurred in a single case (2.1%).

Conclusions

The SCUBA technique provides surgeons with a defined strategy for true endoscopic hematoma evacuation. In particular, the fluid-filled cavity in SCUBA Phase 2 has the potential to provide several advantages over the traditional air-filled strategy, including clear identification and cauterization of bleeding vessels and visualization of residual clot burden. Further investigation is necessary to compare this technique to others that are currently used.

Republished: Intracavitary ultrasound (ICARUS): a neuroendoscopic adaptation of intravascular ultrasound for intracerebral hemorrhage evacuation

Neurosurgeons performing intracerebral hemorrhage evacuation procedures have limited options for monitoring hematoma evacuation and assessing residual hematoma burden intraoperatively. Here, we report the successful neuroendoscopic adaptation of intravascular ultrasound, referred to here as intracavitary ultrasound (ICARUS), in two patients. Pre-evacuation ICARUS demonstrated dense hematomas in both patients. Post-evacuation ICARUS in patient 1 demonstrated significant reduction in clot burden and two focal hyperechoic regions consistent with pockets of hematoma not previously seen with the endoscope or burr hole ultrasound. These areas were directly targeted and resected with the endoscope and suction device. Post-evacuation ICARUS in patient 2 showed significant reduction of hematoma volume without indication of residual blood. ICARUS findings were confirmed on intraoperative DynaCT and postoperative CT 24 hours later. ICARUS is feasibly performed in a hematoma cavity both before and after hematoma aspiration. ICARUS may provide additional information to the operating surgeon and assist in maximizing hematoma removal.

A step-down unit transfer protocol for low-risk aneurysmal subarachnoid hemorrhage

OBJECTIVE

Patients who have experienced subarachnoid hemorrhage (SAH) often receive care in the setting of the ICU. However, SAH patients may not all require extended ICU admission. The authors established a protocol on January 1, 2015, to transfer select, low-risk patients to a step-down unit (SDU) to streamline care for SAH patients. This study describes the results of the implemented protocol.

METHODS

In this retrospective chart review, patients presenting with SAH between January 2011 and September 2016 were reviewed for inclusion. The control group consisted of patients admitted prior to establishment of the SDU transfer protocol, while the intervention group consisted of patients admitted afterward.

RESULTS

Of the patients in the intervention group, 79.2% (57/72) were transferred to the SDU during their admission. Of these transferred patients, 29.8% (17/57) required return to the neurosurgical ICU (NSICU). There were no instances of morbidity or mortality directly related to care in the SDU. Patients in the intervention group had a mean reduced NSICU length of stay, by 1.95 days, which trended toward significance, and a longer average hospitalization, by 2.7 days, which also trended toward significance. In-hospital mortality and 90-day readmission rate were not statistically different between the groups. In addition, early transfer timing prior to 7 days was associated with neither a higher return rate to the NSICU nor higher 90-day readmission rate.

CONCLUSIONS

In this retrospective study, the authors demonstrated that the transfer protocol was safe, feasible, and effective in reducing the ICU length of stay and was independent of transfer timing. Confirmation of these results is needed in a large, multicenter study.

Intracavitary ultrasound (ICARUS): a neuroendoscopic adaptation of intravascular ultrasound for intracerebral hemorrhage evacuation

Neurosurgeons performing intracerebral hemorrhage evacuation procedures have limited options for monitoring hematoma evacuation and assessing residual hematoma burden intraoperatively. Here, we report the successful neuroendoscopic adaptation of intravascular ultrasound, referred to here as intracavitary ultrasound (ICARUS), in two patients. Pre-evacuation ICARUS demonstrated dense hematomas in both patients. Post-evacuation ICARUS in patient 1 demonstrated significant reduction in clot burden and two focal hyperechoic regions consistent with pockets of hematoma not previously seen with the endoscope or burr hole ultrasound. These areas were directly targeted and resected with the endoscope and suction device. Post-evacuation ICARUS in patient 2 showed significant reduction of hematoma volume without indication of residual blood. ICARUS findings were confirmed on intraoperative DynaCT and postoperative CT 24 hours later. ICARUS is feasibly performed in a hematoma cavity both before and after hematoma aspiration. ICARUS may provide additional information to the operating surgeon and assist in maximizing hematoma removal.

Three-Dimensional, computer simulated navigation in endoscopic neurosurgery

BACKGROUND

In order to address the pre- and perioperative need for visualization and prediction of patient-specific anatomy for surgical planning, endoscopic neurosurgeons have increasingly relied on computerized navigation devices to guide their surgical approaches.

OBJECTIVE

This manuscript aims to review: 1) the use of neuronavigation in endoscopic neurosurgery for pre-operative planning, 2) the intraoperative advantages of neuronavigation in endoscopic neurosurgery, and 3) the effects of navigation guidance on operative time, registration accuracy, brain shift, and avoidance of complications. Limitations of the current neuroendoscopic navigation literature will be discussed.

METHODS

We conducted a search using PubMed-MEDLINE; the keywords "stereotactic navigation AND endoscopic surgery" and "simulation AND endoscopic neurosurgery". 36 studies were identified that addressed the use of neuronavigation in endoscopic neurosurgery. These studies were then further analyzed for topics relevant to computerized neuroendoscopy and reviewed for the purposes of this article.

CONCLUSION

Three-dimensional, frameless neuronavigation systems are useful in endoscopic neurosurgery to assist in the pre-operative planning of potential trajectories and to help localize the pathology of interest. Neuronavigation appears to be accurate to < 1-2 mm without issues related to brain shift. Further work is necessary in the investigation of the effect of neuronavigation on operative time, cost, and patient-centered outcomes.

Quantitative Computed Tomography Ventriculography for Assessment and Monitoring of Hydrocephalus: A Pilot Study and Description of Method in Subarachnoid Hemorrhage

BACKGROUND

There is no facile quantitative method for monitoring hydrocephalus (HCP). We propose quantitative computed tomography (CT) ventriculography (qCTV) as a novel computer vision tool for empirically assessing HCP in patients with subarachnoid hemorrhage (SAH).

METHODS

Twenty patients with SAH who were evaluated for ventriculoperitoneal shunt (VPS) placement were selected for inclusion. Ten patients with normal head computed tomography (CTH) findings were analyzed as negative controls. CTH scans were segmented both manually and automatically (by qCTV) to generate measures of ventricular volume.

RESULTS

The median manually calculated ventricular volume was 36.1 cm³ (interquartile range [IQR], 30-115 cm³), which was similar to the median qCTV measured volume of 37.5 cm³ (IQR, 32-118 cm³) (P = 0.796). Patients undergoing VPS placement demonstrated an increase in median ventricular volume on qCTV from 21 cm³ to 40 cm³ on day T-2 and to 51 cm³ by day 0, a change of 144%. This is in contrast to patients who did not require shunting, in whom median ventricular volume decreased from 16 cm³ to 14 cm³ on day T-2 and to 13 cm³ by day 0, with an average overall volume decrease 19% (P = 0.001). The average change in ventricular volume predicted which patients would require VPS placement, successfully identifying 7 of 10 patients (P = 0.004). Using an optimized cutoff of a change in ventricular volume of 2.5 cm³ identified all patients who went on to require VPS placement (10 of 10; P = 0.011).

CONCLUSIONS

qCTV is a reliable means of quantifying ventricular volume and hydrocephalus. This technique offers a new tool for monitoring neurosurgical patients for hydrocephalus, and may be beneficial for use in future research studies, as well as in the routine care of patients with hydrocephalus.

Abstract WMP22: Multiparametric CT Perfusion to Determine the Collaterals Status in Patients With Acute Ischemic Stroke: A New Perfusion Index

Introduction: Good collateral flow is an independent predictor of reperfusion that can be used to extend the treatment window in the new era of endovascular therapies for patients with acute ischemic stroke (AIS). Using a multiparametric approach, we aimed to identify perfusion parameter/s that can represent the extent of collaterals in comparison to CTA.

Methods: AIS patients with anterior circulation large vessel occlusion who had baseline CTA and CT perfusion were included. CT perfusion data were processed by Bayesian method to generate arterial tissue delay (ATD) maps at thresholds of 2 & 6 seconds. The volume of mild delayed perfusion (Vol-ATD >2sec ), moderate delayed (Vol-ATD 2-6sec ) and critical delayed perfusion (Vol-ATD >6sec ) in addition to corresponding rCBV and rCBF were calculated. Baseline CTA collaterals were scored using an established scoring scale1 and dichotomized to poor or good. The association of perfusion parameters and status of collaterals was assessed by repeated measure of analyses and receiver operating characteristic (ROC).

Results: In 28 patients included, 16 had good collaterals on CTA. After controlling for age, sex, baseline NIHSS and type of treatment, multivariate logistic regression analysis identified rCBV (p<0.001) and ATD 2-6sec (p=0.003), but not rCBF, Vol-ATD > 2sec or Vol-ATD >6sec , as independent predictors of good collaterals. ROC analysis showed AUC of 0.88 (sensitivity/specificity: 75%/100%) for rCBV and AUC of 0.84 (sensitivity/specificity: 93%/67%) for Vol-ATD 2-6sec . We defined a perfusion collateral index (PCI) calculated from Vol-ATD 2-6sec x its rCBV, that remained an independent predictor of good collaterals with improved diagnostic accuracy over each measure alone resulting in nominal AUC of 1 (sensitivity/specificity: 100%/100%).

Conclusions: Multiparametric CT perfusion can be used to assess the status of collaterals in patients with AIS. Perfusion collateral index (PCI) defined as Vol-ATD 2-6sec x rCBV is a new perfusion index with a nominal diagnostic accuracy of 100% compared to baseline CTA to predict status of collaterals in our small cohort. Our results need to be validated in a larger prospective cohort.

Impact of Neurosurgery Medical Student Research Grants on Neurosurgery Residency Choice

BACKGROUND

Recent decades have seen a rapid expansion of involvement of medical students in biomedical research during medical school training. Research within medical school has been shown to influence medical students with regard to medical knowledge, career development, and residency specialty choice. The objective of this study was to evaluate the impact of neurosurgery medical student research grants on neurosurgery residency choice and provide an insight on the demographics of grant awardees.

METHODS

In this retrospective study, a search of award recipients was performed using data available on the American Association of Neurological Surgeons, Congress of Neurological Surgeons, and Neurosurgery Research and Education Foundation websites. Searched years included the first cycle of American Association of Neurological Surgeons/Neurosurgery Research and Education Foundation (2007) and Council of State Neurosurgical Societies/Congress of Neurological Surgeons (2008-2009) grant awards until the 2015-2016 cycle, which is the latest award cycle to date.

RESULTS

The initial search yielded 163 research grants that were awarded to 158 students between the years of 2007 and 2016. Among the 163 grant recipients, 126 (77.3%) were men. Among the 88 recipients who entered postgraduate residency programs, 51% (45 of 88) matched into neurosurgery residency. When considering both neurosurgery and neurology residency programs, the percentage increased to 59.1% (52 of 88).

CONCLUSIONS

Neurosurgery grants for medical students are highly successful in producing future neurosurgeons with >50% of grant recipients matched into neurosurgery. Women are underrepresented in neurosurgery grants and neurosurgery residency programs. This situation can be improved by providing insight about the field early in medical school, perhaps through increased use of neurosurgery medical student grants.

Effect of Prior Embolization on Cerebral Arteriovenous Malformation Radiosurgery Outcomes: A Case-Control Study

BACKGROUND

Embolization before stereotactic radiosurgery (SRS) for cerebral arteriovenous malformations (AVM) has been shown to negatively affect obliteration rates, but its impact on the risks of radiosurgery-induced complications and latency period hemorrhage is poorly defined.

OBJECTIVE

To determine, in a case-control study, the effect of prior embolization on AVM SRS outcomes.

METHODS

We evaluated a database of AVM patients who underwent SRS. Propensity score analysis was used to match the case (embolized nidi) and control (nonembolized nidi) cohorts. AVM angioarchitectural complexity was defined as the sum of the number of major feeding arteries and draining veins to the nidus. Multivariate Cox proportional hazards regression analyses were performed on the overall study population to determine independent predictors of obliteration and radiation-induced changes.

RESULTS

The matching process yielded 242 patients in each cohort. The actuarial obliteration rates were significantly lower in the embolized (31%, 49% at 5, 10 years, respectively) compared with the nonembolized (48%, 64% at 5, 10 years, respectively) cohort (P = .003). In the multivariate analysis for obliteration, lower angioarchitectural complexity (P < .001) and radiologically evident radiation-induced changes (P = .016) were independent predictors, but embolization was not significant (P = .744). In the multivariate analysis for radiologic radiation-induced changes, lack of prior embolization (P = .009) and fewer draining veins (P = .011) were independent predictors.

CONCLUSION

The effect of prior embolization on AVM obliteration after SRS may be significantly confounded by nidus angioarchitectural complexity. Additionally, embolization could reduce the risk of radiation-induced changes. Thus, combined embolization and SRS may be warranted for appropriately selected nidi.

The impact of evidence: evolving therapy for acute ischemic stroke in a large healthcare system

BACKGROUND

With a recent surge of clinical trials, the treatment of ischemic stroke has undergone dramatic changes.

OBJECTIVE

To evaluate the impact of evidence and a revamped stroke protocol on a large healthcare system.

METHODS

A retrospective review of 69 patients with ischemic stroke treated with intra-arterial therapy was carried out. Cohort 1 included patients treated before implementation of a new stroke protocol, and cohort 2 after implementation. Angiographic outcome was graded using the Thrombolysis in Cerebral Infarction (TICI) score. Clinical outcomes were assessed using the National Institute of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS).

RESULTS

Primary outcomes comparing cohorts demonstrated decreased arrival-to-puncture time (cohort 2: 104 vs cohort 1: 181 min, p<0.001), similar TICI 2b/3 rates (86.5% vs 81.3%, p=0.5530), and similar percentage of patients with discharge mRS 0-2 (18.9% vs 21.9%, p=0.7740). Notable secondary outcomes for cohort 2 included decreased puncture-to-first pass time (34 vs 53 min, p <0.001), increased TICI 3 rates (37.8% vs 18.8%, p=0.0290), a trend toward greater improvements in NIHSS on postoperative day 1 (6.8 vs 2.6, p=0.0980) and discharge (9.5 vs 6.7, p=0.1130), and a trend toward increased percentage of patients discharged with mRS 0-3 (48.6% vs 34.4%, p=0.3280 NS). There were similar rates of symptomatic intracerebral hemorrhage (10.8% vs 9.4%, p=0.9570) and death (10.8% vs 15.6%, p=0.5530).

CONCLUSIONS

An interdisciplinary and rapid response to the emergence of strong clinical evidence can result in dramatic changes in a large healthcare system.

Association of a Distal Intradural-Extracranial Posterior Inferior Cerebellar Artery Aneurysm With Chiari Type I Malformation

BACKGROUND AND IMPORTANCE:

Distal extracranial posterior inferior cerebellar artery (PICA) aneurysms are very rare lesions and have not been previously reported in association with a Chiari type I malformation (CMI).

CLINICAL PRESENTATION:

A 56-year-old woman with a distal, low-lying, intradural-extracranial PICA aneurysm presented with a subarachnoid hemorrhage and was treated with coil embolization. The patient presented again 1 month later with symptoms of a CMI and was found to have tonsillar herniation and a large syrinx that appeared to be exacerbated by the coil mass. The patient was re-treated with a suboccipital craniectomy, C1-2 laminectomy, aneurysm trapping and excision, end-to-end PICA anastomosis, and expansile duraplasty.

CONCLUSION:

Although just a single case, important teaching points regarding the angiographic appearance of a CMI and treatment options for distal PICA aneurysms that are situated below the foramen magnum can be learned. A low-lying caudal PICA loop should trigger a workup for a CMI. Caution should be taken when using coil embolization for aneurysms in the high cervical spinal canal. Bypass with aneurysm trapping and excision may be a superior treatment option in these cases because the posterior fossa and high cervical canal can be concomitantly decompressed. To our knowledge, this is the only case reported of a distal intradural-extracranial PICA aneurysm associated with a CMI.

Ophthalmic artery occlusion immediately following placement of a flow diverter without clinical sequelae

Branch vessel occlusion is a potential consequence following flow diverter placement for intracranial aneurysms, but the frequency and clinical impact has not been completely elucidated. In this case of a 45-year-old woman with a large left internal carotid artery aneurysm, the ophthalmic artery was covered by two flow diverters and was acutely occluded along with the aneurysm. Common carotid injections failed to demonstrate collateral flow to the ophthalmic artery via the external carotid artery. Nonetheless, the patient woke from anesthesia with objectively stable and subjectively improved vision. This case demonstrates that an acute occlusion of the ophthalmic artery without external carotid artery collaterals can be tolerated clinically.