Systematic evaluation and plan quality assessment of the Leksell® gamma knife® lightning dose optimizer.

To compare stereotactic radiosurgery (SRS) plan quality metrics of manual forward planning (MFP) and Elekta Fast Inverse Planning™ (FIP)-based inversely optimized plans for patients treated with Gamma Knife®. Clinically treated, MFP SRS plans for 100 consecutive patients (115 lesions; 67 metastatic and 48 benign) were replanned with the FIP dose optimizer based on a convex linear programming formulation. Comparative plans were generated to match or exceed the following metrics in order of importance: Target Coverage (TC), Paddick Conformity Index (PCI), beam-on time (BOT), and Gradient Index (GI). Plan quality metrics and delivery parameters between MFP and FIP were compared for all lesions and stratified into subgroups for further analysis. Additionally, performance of FIP for multiple punctate (<4 mm) metastatic lesions on a subset of cases was investigated. A Wilcoxon signed-rank test for non-normal distributions was used to assess the statistical differences between the MFP and FIP treatment plans. Overall, 76% (87/115) of FIP plans showed a statistically significant improvement in plan quality compared to MFP plans. As compared to MFP, FIP plans demonstrated an increase in the median PCI by 1.1% (p<0.01), a decrease in GI by 3.7% (p< 0.01), and an increase in median number of shots by 74% (p< 0.01). TC and BOT were not statistically significantly different between MFP and FIP plans (p>0.05). FIP plans showed a statistically significant increase in use of 16 mm (p< 0.01) and blocked shots (p< 0.01), with a corresponding decrease in 4 mm shots (p< 0.01). Use of multiple shots per coordinate was significantly higher in FIP plans (p<0.01). The FIP optimizer failed to generate a clinically acceptable plan in 4/115 (3.5%) lesions despite optimization parameter changes. The mean optimization time for FIP plans was 5.0 min (Range: 1.0 - 10.0 min). In the setting of multiple punctate lesions, PCI for FIP was significantly improved (p<0.01) by changing the default low-dose/BOT penalty optimization setting from a default of 50/50 to 75-85/40. FIP offers a significant reduction in manual effort for SRS treatment planning while achieving comparable plan quality to an expert planner-substantially improving overall planning efficiency. FIP plans employ a non-intuitive increased use of blocked sectors and shot-in-shot technique to achieve high quality plans. Several FIP plans failed to achieve clinically acceptable treatments and warrant further investigation.

Factors associated with unplanned readmissions and costs following resection of brain metastases in the United States.

The purpose of this study was to critically analyze the risk of unplanned readmission following resection of brain metastasis and to identify key risk factors to allow for early intervention strategies in high-risk patients. We analyzed data from the Nationwide Readmissions Database (NRD) from 2010-2014, and included patients who underwent craniotomy for brain metastasis, identified using ICD-9-CM diagnosis (198.3) and procedure (01.59) codes. The primary outcome of the study was unplanned 30-day all-cause readmission rate. Secondary outcomes included reasons and costs of readmissions. Hierarchical logistic regression model was used to identify the factors associated with 30-day readmission following craniotomy for brain metastasis. During the study period, 44,846 index hospitalizations occurred for patients who underwent resection of brain metastasis. In this cohort, 17.8% (n = 7,965) had unplanned readmissions within the first 30 days after discharge from the index hospitalization. The readmission rate did not change significantly during the five-year study period (p-trend = 0.286). The median per-patient cost for 30-day unplanned readmission was $11,109 and this amounted to a total of $26.4 million per year, which extrapolates to a national expenditure of $269.6 million. Increasing age, male sex, insurance status, Elixhauser comorbidity index, length of stay, teaching status of the hospital, neurological complications and infectious complications were associated with 30-day readmission following discharge after an index admission for craniotomy for brain metastasis. Unplanned readmission rates after resection of brain metastasis remain high and involve substantial healthcare expenditures. Developing tools and interventions to prevent avoidable readmissions could focus on the high-risk patients as a future strategy to decrease substantial healthcare expense.

A Safe Transitions Pathway for post-craniotomy neurological surgery patients: high-value care that bypasses the intensive care unit.

OBJECTIVE: High-value medical care is described as care that leads to excellent patient outcomes, high patient satisfaction, and efficient costs. Neurosurgical care in particular can be expensive for the hospital, as substantial costs are accrued during the operation and throughout the postoperative stay. The authors developed a "Safe Transitions Pathway" (STP) model in which select patients went to the postanesthesia care unit (PACU) and then the neuro-transitional care unit (NTCU) rather than being directly admitted to the neurosciences intensive care unit (ICU) following a craniotomy. They sought to evaluate the clinical and financial outcomes as well as the impact on the patient experience for patients who participated in the STP and bypassed the ICU level of care. METHODS: Patients were enrolled during the 2018 fiscal year (FY18; July 1, 2017, through June 30, 2018). The electronic medical record was reviewed for clinical information and the hospital cost accounting record was reviewed for financial information. Nurses and patients were given a satisfaction survey to assess their respective impressions of the hospital stay and of the recovery pathway. RESULTS: No patients who proceeded to the NTCU postoperatively were upgraded to the ICU level of care postoperatively. There were no deaths in the STP group, and no patients required a return to the operating room during their hospitalization (95% CI 0%-3.9%). There was a trend toward fewer 30-day readmissions in the STP patients than in the standard pathway patients (1.2% [95% CI 0.0%-6.8%] vs 5.1% [95% CI 2.5%-9.1%], p = 0.058). The mean number of ICU days saved per case was 1.20. The average postprocedure length of stay was reduced by 0.25 days for STP patients. Actual FY18 direct cost savings from 94 patients who went through the STP was $422,128. CONCLUSIONS: Length of stay, direct cost per case, and ICU days were significantly less after the adoption of the STP, and ICU bed utilization was freed for acute admissions and transfers. There were no substantial complications or adverse patient outcomes in the STP group.

Insurance type impacts the economic burden and survival of patients with newly diagnosed glioblastoma.

OBJECTIVE: Glioblastoma (GBM) carries a high economic burden for patients and caregivers, much of which is associated with initial surgery. The authors investigated the impact of insurance status on the inpatient hospital costs of surgery for patients with GBM. METHODS: The authors conducted a retrospective review of patients with GBM (2010-2015) undergoing their first resection at the University of California, San Francisco, and corresponding inpatient hospital costs. RESULTS: Of 227 patients with GBM (median age 62 years, 37.9% females), 31 (13.7%) had Medicaid, 94 (41.4%) had Medicare, and 102 (44.9%) had private insurance. Medicaid patients had 30% higher overall hospital costs for surgery compared to non-Medicaid patients ($50,285 vs $38,779, p = 0.01). Medicaid patients had higher intensive care unit (ICU; p < 0.01), operating room (p < 0.03), imaging (p < 0.001), room and board (p < 0001), and pharmacy (p < 0.02) costs versus non-Medicaid patients. Medicaid patients had significantly longer overall and ICU lengths of stay (6.9 and 2.6 days) versus Medicare (4.0 and 1.5 days) and privately insured patients (3.9 and 1.8 days, p < 0.01). Medicaid patients had similar comorbidity rates to Medicare patients (67.8% vs 68.1%), and both groups had higher comorbidity rates than privately insured patients (37.3%, p < 0.0001). Only 67.7% of Medicaid patients had primary care providers (PCPs) versus 91.5% of Medicare and 86.3% of privately insured patients (p = 0.009) at the time of presentation. Tumor diameter at diagnosis was largest for Medicaid (4.7 cm) versus Medicare (4.1 cm) and privately insured patients (4.2 cm, p = 0.03). Preoperative (70 vs 90, p = 0.02) and postoperative (80 vs 90, p = 0.03) Karnofsky Performance Scale (KPS) scores were lowest for Medicaid versus non-Medicaid patients, while in subgroup analysis, postoperative KPS score was lowest for Medicaid patients (80, vs 90 for Medicare and 90 for private insurance; p = 0.03). Medicaid patients had significantly shorter median overall survival (10.7 months vs 12.8 months for Medicare and 15.8 months for private insurance; p = 0.02). Quality-adjusted life year (QALY) scores were 0.66 and 1.05 for Medicaid and non-Medicaid patients, respectively (p = 0.036). The incremental cost per QALY was $29,963 lower for the non-Medicaid cohort. CONCLUSIONS: Patients with GBMs and Medicaid have higher surgical costs, longer lengths of stay, poorer survival, and lower QALY scores. This study indicates that these patients lack PCPs, have more comorbidities, and present later in the disease course with larger tumors; these factors may drive the poorer postoperative function and greater consumption of hospital resources that were identified. Given limited resources and rising healthcare costs, factors such as access to PCPs, equitable adjuvant therapy, and early screening/diagnosis of disease need to be improved in order to improve prognosis and reduce hospital costs for patients with GBM.

Disparities in health care determine prognosis in newly diagnosed glioblastoma.

OBJECTIVE Glioblastoma (GBM) is an aggressive brain malignancy with a short overall patient survival, yet there remains significant heterogeneity in outcomes. Although access to health care has previously been linked to impact on prognosis in several malignancies, this question remains incompletely answered in GBM. METHODS This study was a retrospective analysis of 354 newly diagnosed patients with GBM who underwent first resection at the authors' institution (2007-2015). RESULTS Of the 354 patients (median age 61 years, and 37.6% were females), 32 (9.0%) had no insurance, whereas 322 (91.0%) had insurance, of whom 131 (40.7%) had Medicare, 45 (14%) had Medicaid, and 146 (45.3%) had private insurance. On average, insured patients survived almost 2-fold longer (p < 0.0001) than those who were uninsured, whereas differences between specific insurance types did not influence survival. The adjusted hazard ratio (HR) for death was higher in uninsured patients (HR 2.27 [95% CI 1.49-3.33], p = 0.0003). Age, mean household income, tumor size at diagnosis, and extent of resection did not differ between insured and uninsured patients, but there was a disparity in primary care physician (PCP) status-none of the uninsured patients had PCPs, whereas 72% of insured patients had PCPs. Postoperative adjuvant treatment rates with temozolomide (TMZ) and radiation therapy (XRT) were significantly less in uninsured (TMZ in 56.3%, XRT in 56.3%) than in insured (TMZ in 75.2%, XRT in 79.2%; p = 0.02 and p = 0.003) patients. Insured patients receiving both agents had better prognosis than uninsured patients receiving the same treatment (9.1 vs 16.34 months; p = 0.025), suggesting that the survival effect in insured patients could only partly be explained by higher treatment rates. Moreover, having a PCP increased survival among the insured cohort (10.7 vs 16.1 months, HR 1.65 [95% CI 1.27-2.15]; p = 0.0001), which could be explained by significant differences in tumor diameter at initial diagnosis between patients with and without PCPs (4.3 vs 4.8 cm, p = 0.003), and a higher rate of clinical trial enrollment, suggesting a critical role of PCPs for a timelier diagnosis of GBM and proactive cancer care management. CONCLUSIONS Access to health care is a strong determinant of prognosis in newly diagnosed patients with GBM. Any type of insurance coverage and having a PCP improved prognosis in this patient cohort. Higher rates of treatment with TMZ plus XRT, clinical trial enrollment, fewer comorbidities, and early diagnosis may explain survival disparities. Lack of health insurance or a PCP are major challenges within the health care system, which, if improved upon, could favorably impact the prognosis of patients with GBM.

Cost-effectiveness development for the postoperative care of craniotomy patients: a safe transitions pathway in neurological surgery.

OBJECTIVE The authors' institution is in the top 5th percentile for hospital cost in the nation, and the neurointensive care unit (NICU) is one of the costliest units. The NICU is more expensive than other units because of lower staff/patient ratio and because of the equipment necessary to monitor patient care. The cost differential between the NICU and Neuro transitional care unit (NTCU) is $1504 per day. The goal of this study was to evaluate and to pilot a program to improve efficiency and lower cost by modifying the postoperative care of patients who have undergone a craniotomy, sending them to the NTCU as opposed to the NICU. Implementation of the pilot will expand and utilize neurosurgery beds available on the NTCU and reduce the burden on NICU beds for critically ill patient admissions. METHODS Ten patients who underwent craniotomy to treat supratentorial brain tumors were included. Prior to implementation of the pilot, inclusion criteria were designed for patient selection. Patients included were less than 65 years of age, had no comorbid conditions requiring postoperative intensive care unit (ICU) care, had a supratentorial meningioma less than 3 cm in size, had no intraoperative events, had routine extubation, and underwent surgery lasting fewer than 5 hours and had blood loss less than 500 ml. The Safe Transitions Pathway (STP) was started in August 2016. RESULTS Ten tumor patients have utilized the STP (5 convexity meningiomas, 2 metastatic tumors, 3 gliomas). Patients' ages ranged from 29 to 75 years (median 49 years; an exception to the age limit of 65 years was made for one 75-year-old patient). Discharge from the hospital averaged 2.2 days postoperative, with 1 discharged on postoperative day (POD) 1, 7 discharged on POD 2, 1 discharged on POD 3, and 1 discharged on POD 4. Preliminary data indicate that quality and safety for patients following the STP (moving from the operating room [OR] to the neuro transitional care unit [OR-NTCU]) are no different from those of patients following the traditional OR-NICU pathway. No patients required escalation in level of nursing care, and there were no readmissions. This group has been followed for greater than 1 month, and there were no morbidities. CONCLUSIONS The STP is a new and efficient pathway for the postoperative care of neurosurgery patients. The STP has reduced hospital cost by $22,560 for the first 10 patients, and there were no morbidities. Since this pilot, the authors have expanded the pathway to include other surgical cases and now routinely schedule craniotomy patients for the (OR-NTCU) pathway. The potential cost reduction in one year could reach $500,000 if we reach our potential of 20 patients per month.

Targeted reduction in neurosurgical laboratory utilization: resident-led effort at a single academic institution.

OBJECT: Given economic limitations and burgeoning health care costs, there is a need to minimize unnecessary diagnostic laboratory tests. METHODS: The authors studied whether a financial incentive program for trainees could lead to fewer unnecessary laboratory tests in neurosurgical patients in a large, 600-bed academic hospital setting. The authors identified 5 laboratory tests that ranked in the top 13 of the most frequently ordered during the 2010-2011 fiscal year, yet were least likely to be abnormal or influence patient management. RESULTS: In a single year of study, there was a 47% reduction in testing of serum total calcium, ionized calcium, chloride, magnesium, and phosphorus. This reduction led to a savings of $1.7 million in billable charges to health care payers and $75,000 of direct costs to the medical center. In addition, there were no significant negative changes in the quality of care delivered, as recorded in a number of metrics, showing that this cost savings did not negatively impact patient care. CONCLUSIONS: Engaging physician trainees in quality improvement can be successfully achieved by financial incentives. Through the resident-led quality improvement incentive program, neurosurgical trainees successfully reduced unnecessary laboratory tests, resulting in significant cost savings to both the medical center and the health care system. Similar programs that engage trainees could improve the value of care being provided at other academic medical centers.

Functional mapping-guided resection of low-grade gliomas in eloquent areas of the brain: improvement of long-term survival. Clinical article.

OBJECT: Low-grade gliomas (LGGs) frequently infiltrate highly functional or "eloquent" brain areas. Given the lack of long-term survival data, the prognostic significance of eloquent brain tumor location and the role of functional mapping during resective surgery in presumed eloquent brain regions are unknown. METHODS: We performed a retrospective analysis of 281 cases involving adults who underwent resection of a supratentorial LGG at a brain tumor referral center. Preoperative MR images were evaluated blindly for involvement of eloquent brain areas, including the sensorimotor and language cortices, and specific subcortical structures. For high-risk tumors located in presumed eloquent brain areas, long-term survival estimates were evaluated for patients who underwent intraoperative functional mapping with electrocortical stimulation and for those who did not. RESULTS: One hundred and seventy-four patients (62%) had high-risk LGGs that were located in presumed eloquent areas. Adjusting for other known prognostic factors, patients with tumors in areas presumed to be eloquent had worse overall and progression-free survival (OS, hazard ratio [HR] 6.1, 95% CI 2.6-14.1; PFS, HR 1.9, 95% CI 1.2-2.9; Cox proportional hazards). Confirmation of tumor overlapping functional areas during intraoperative mapping was strongly associated with shorter survival (OS, HR 9.6, 95% CI 3.6-25.9). In contrast, when mapping revealed that tumor spared true eloquent areas, patients had significantly longer survival, nearly comparable to patients with tumors that clearly involved only noneloquent areas, as demonstrated by preoperative imaging (OS, HR 2.9, 95% CI 1.0-8.5). CONCLUSIONS: Presumed eloquent location of LGGs is an important but modifiable risk factor predicting disease progression and death. Delineation of true functional and nonfunctional areas by intraoperative mapping in high-risk patients to maximize tumor resection can dramatically improve long-term survival.

Assessment of image guided accuracy in a skull model: comparison of frameless stereotaxy techniques vs. frame-based localization.

INTRODUCTION: The use of image-guided systems (IGS) for brain biopsy has increased in neurosurgical practice. We sought to evaluate the accuracy of a plastic, disposable burr hole mounted guide for stereotactic biopsy using an IGS and compare the results of different targeting methods with those of frame based localization. METHODS: MRIs were performed on a skull model with mounted fiducials with a stereotactic frame in place and data was loaded onto the Stealth IGS. The model was placed in a Mayfield head holder and fixed to the OR table. Registration of imaging to physical space was carried out. Using three different targeting methods on the Stealth IGS, the distance between the target and the predicted position of the target, the offset error, was measured in three dimensions and confirmed by 2 observers. A sum of squares for the 3 offset errors in all planes was used to calculate the summed vector error. The same MRI dataset used with the Cosman-Roberts-Wells (CRW) stereotactic frame for comparison. The summed vector error was calculated in the same manner to compare the accuracy of targeting with these guides to the frame-based CRW system. RESULTS: For frameless stereotaxy using the "Straight- guide 4 2D" targeting method the mean error was 2.58 +/- 0.51 mm (n=12). The vector error was 5.23 +/- 0.54 (n=4). For the registration set and target using the "Offset- guide 4 2D" targeting method the mean error was 1.66 +/- 0.36 mm (n=12). The vector error was 3.32 +/- 0.72 (n=4). The best localization was obtained with the "probe's eye" planning and targeting. The mean error was 0.33 +/- 0.16 mm (n=12). The vector error was 1.0 +/- 0.28 (n=4). We found a statistical difference between the different techniques (P<0.001) (Kruskal-Wallis One Way Analysis of Variance on Ranks). An all pairwise multiple comparison procedure (Holm-Sidak method) found an overall significance level = 0.05. For the frame-based CRW the mean error from the target was 1.03 +/- 0.19 mm (n=18) and the mean target localization error vector was 2.23 +/- 0.14 (n=6). We found a statistically significant difference between NDT guide "Probes Eye" vs. the MR-CRW (P=0.003, Mann-Whitney Rank Sum Test). CONCLUSIONS: These results indicate that using MR imaging, surgical planning software and the skull mounted Navigus-DT with the probe's eye view option for targeting, localization accuracy appears to fall within acceptable ranges compared with frame-based methods which have been the standards for stereotactic brain biopsy and functional neurosurgery. Furthermore, there may be considerable differences in accuracy between different targeting methods.

Frame-based stereotactic biopsy remains an important diagnostic tool with distinct advantages over frameless stereotactic biopsy.

OBJECT: As the availability of image-guided surgical navigation systems has increased, the application of frame-based biopsy has declined at our institution, despite equivalent accuracy and safety. There are several cost issues separating the use of surgical navigation systems and stereotactic frames for simple biopsy which may have implications in this era of health care cost control. We retrospectively reviewed the UCSF experience with stereotactic brain biopsy from a 9 year period. METHODS: Data were collected for 213 consecutive stereotactic brain biopsies performed at UCSF (139 frame-based and 74 frameless). There were no significant differences between the frame-based and frameless biopsy groups with regard to patient demographics, overall histopathology, proportion of nondiagnostic biopsies, or incidence of complications. General anesthesia was used for 9 (6%) and 70 (95%) of the frame-based and frameless biopsy cases, respectively. Frame-based biopsies required a mean of 114+/-3 min of operating room time, while frameless biopsies required 185+/-6 min (P<0.0001). For patients admitted to our neurosurgery service who underwent frame-based (n=110) or frameless (n=52) biopsy within 24 h of admission, the mean lengths of hospital stay were 1.8+/-0.2 and 3.2+/-0.6 days, respectively (P=0.007). CONCLUSION: Frame-based and frameless stereotactic biopsy approaches were equally effective at providing a tissue diagnosis with minimum morbidity and mortality. The frame-based approach, however, required significantly less anesthesia resources, less operating room time and shorter hospital stays, and thus should still be considered a first-line approach for stereotactic brain biopsy.

Prizes, lectures, and awards of the American Association of Neurological Surgeons/Congress of Neurological Surgeons Section on Tumors.

An important goal of the Section on Tumors of the American Association of Neurological Surgeons (AANS) and Congress of Neurological Surgeons (CNS) since its founding in 1985 has been to foster both education and research in the field of brain tumor treatment. As one means of achieving this, the Section awards a number of prizes, research grants, and named lectures at the annual meetings of the AANS and CNS. After a brief examination of similar honors that were given in recognition of pioneering work by Knapp, Cushing, and other early brain tumor researchers, the authors describe the various awards given by the AANS/CNS Section on Tumors since its founding, their philanthropic donors, and the recipients of the awards. The subsequent career of the recipients is briefly examined, in terms of the rate of full publication of award-winning abstracts and achievement of grant funding by awardees.