Surgical management of Rathke cleft cysts in pediatric patients: a single institution experience.

OBJECTIVE: Rathke cleft cysts (RCCs) are benign, epithelial-lined sellar lesions that arise from remnants of the craniopharyngeal duct. Due to their rarity in the pediatric population, data are limited regarding the natural history and optimal management of growing or symptomatic RCCs. We present our institutional experience with the surgical management of RCCs. METHODS: We performed a retrospective study of consecutive RCC patients ≤ 18 years old treated surgically at our institution between 2006 and 2022. RESULTS: Overall, 567 patients with a diagnosis of pituitary mass or cyst were identified. Of these, 31 had a histopathological diagnosis of RCC, 58% female and 42% male. The mean age was 13.2 ± 4.2 years. Presenting symptoms included headache (58%), visual changes (32%), and endocrinopathies or growth delay (26%); 13% were identified incidentally and subsequently demonstrated growth on serial imaging. Six percent presented with symptomatic intralesional hemorrhage. Surgical approach was transsphenoidal for 90% of patients and orbitozygomatic for 10%. Preoperative headaches resolved in 61% of patients and preoperative visual deficits improvement in 55% after surgery. New pituitary axis deficits were seen in 9.7% of patients. Only two complications occurred from a first-time surgery: one cerebrospinal fluid leak requiring lumbar drain placement, and one case of epistaxis requiring cauterization. No patients experienced new visual or neurological deficits. Patients were followed postoperatively with serial imaging at a mean follow-up was 62.9 ± 58.4 months. Recurrence requiring reoperation occurred in 32% of patients. Five-year progression-free survival was 47.9%. Except for one patient with multiple neurological deficits from a concurrent tectal glioma, all patients had a modified Rankin Scale score of 0 or 1 (good outcome) at last follow-up. CONCLUSION: Due to their secretory epithelium, pediatric RCCs may demonstrate rapid growth and can cause symptoms due to local mass effect. Surgical management of symptomatic or growing pediatric RCCs via cyst fenestration or partial resection of the cyst wall can be performed safely, with good neurologic outcomes. There is a nontrivial risk of endocrinologic injury, and long-term follow up is needed due to high recurrence rates.

Frequency and predictors of concurrent complications in multi-suture release for syndromic craniosynostosis.

PURPOSE: Understanding the complication profile of craniosynostosis surgery is important, yet little is known about complication co-occurrence in syndromic children after multi-suture craniosynostosis surgery. We examined concurrent perioperative complications and predictive factors in this population. METHODS: In this retrospective cohort study, children with syndromic diagnoses and multi-suture involvement who underwent craniosynostosis surgery in 2012-2020 were identified from the National Surgical Quality Improvement Program-Pediatric database. The primary outcome was concurrent complications; factors associated with concurrent complications were identified. Correlations between complications and patient outcomes were assessed. RESULTS: Among 5,848 children identified, 161 children (2.75%) had concurrent complications: 129 (2.21%) experienced two complications and 32 (0.55%) experienced ≥ 3. The most frequent complication was bleeding/transfusion (69.53%). The most common concurrent complications were transfusion/superficial infection (27.95%) and transfusion/deep incisional infection (13.04%) or transfusion/sepsis (13.04%). Two cardiac factors (major cardiac risk factors (odds ratio (OR) 3.50 [1.92-6.38]) and previous cardiac surgery (OR 4.87 [2.36-10.04])), two pulmonary factors (preoperative ventilator dependence (OR 3.27 [1.16-9.21]) and structural pulmonary/airway abnormalities (OR 2.89 [2.05-4.08])), and preoperative nutritional support (OR 4.05 [2.34-7.01]) were independently associated with concurrent complications. Children who received blood transfusion had higher odds of deep surgical site infection (OR 4.62 [1.08-19.73]; p = 0.04). CONCLUSIONS: Our results indicate that several cardiac and pulmonary risk factors, along with preoperative nutritional support, were independently associated with concurrent complications but procedural factors were not. This information can help inform presurgical counseling and preoperative risk stratification in this population.

Treatment of pediatric intracranial aneurysms: institutional case series and systematic literature review.

INTRODUCTION: Pediatric intracranial aneurysms (IAs) are rare and have distinct clinical profiles compared to adult IAs. They differ in location, size, morphology, presentation, and treatment strategies. We present our experience with pediatric IAs over an 18-year period using surgical and endovascular treatments and review the literature to identify commonalities in epidemiology, treatment, and outcomes. METHODS: We identified all patients < 20 years old who underwent treatment for IAs at our institution between 2005 and 2020. Medical records and imaging were examined for demographic, clinical, and operative data. A systematic review was performed to identify studies reporting primary outcomes of surgical and endovascular treatment of pediatric IAs. Demographic information, aneurysm characteristics, treatment strategies, and outcomes were collected. RESULTS: Thirty-three patients underwent treatment for 37 aneurysms over 18 years. The mean age was 11.4 years, ranging from one month to 19 years. There were 21 males (63.6%) and 12 females (36.4%), yielding a male: female ratio of 1.75:1. Twenty-six (70.3%) aneurysms arose from the anterior circulation and 11 (29.7%) arose from the posterior circulation. Aneurysmal rupture occurred in 19 (57.5%) patients, of which 8 (24.2%) were categorized as Hunt-Hess grades IV or V. Aneurysm recurrence or rerupture occurred in five (15.2%) patients, and 5 patients (15.2%) died due to sequelae of their aneurysms. Twenty-one patients (63.6%) had a good outcome (modified Rankin Scale score 0-2) on last follow up. The systematic literature review yielded 48 studies which included 1,482 total aneurysms (611 with endovascular treatment; 656 treated surgically; 215 treated conservatively). Mean aneurysm recurrence rates in the literature were 12.7% and 3.9% for endovascular and surgical treatment, respectively. CONCLUSIONS: Our study provides data on the natural history and longitudinal outcomes for children treated for IAs at a single institution, in addition to our treatment strategies for various aneurysmal morphologies. Despite the high proportion of patients presenting with rupture, good functional outcomes can be achieved for most patients.

A cost analysis of MR-guided laser interstitial thermal therapy for adult refractory epilepsy.

OBJECTIVE: MR-guided laser interstitial thermal therapy (LITT) is used increasingly for refractory epilepsy. The goal of this investigation is to directly compare cost and short-term adverse outcomes for adult refractory epilepsy treated with temporal lobectomy and LITT, as well as to identify risk factors for increased costs and adverse outcomes. METHODS: The National Inpatient Sample (NIS) was queried for patients who received LITT between 2012 and 2019. Patients with adult refractory epilepsy were identified. Multivariable mixed-effects models were used to analyze predictors of cost, length of stay (LOS), and complications. RESULTS: LITT was associated with reduced LOS and overall cost relative to temporal lobectomy, with a statistical trend toward lower incidence of postoperative complications. High-volume surgical epilepsy centers had lower LOS overall. Longer LOS was a significant driver of increased cost for LITT, and higher comorbidity was associated with non-routine discharge. SIGNIFICANCE: LITT is an affordable alternative to temporal lobectomy for adult refractory epilepsy with an insignificant reduction in inpatient complications. Patients may benefit from expanded access to this treatment modality for both its reduced LOS and lower cost.

Going the distance in acoustic neuroma resection: microsurgical outcomes at high-volume centers of excellence.

PURPOSE: High-volume hospitals are associated with improved surgical outcomes for acoustic neuromas (ANs). Due to the benign and slow-growing nature of ANs, many patients travel to geographically distant cities, states, or countries for their treatment. However, the impact of travel burden to high-volume centers, as well as its relative benefit are poorly understood. We compared post-operative outcomes between AN patients that underwent treatment at local, low-volume hospitals with those that traveled long distances to high-volume hospitals. METHODS: The National Cancer Database was used to analyze AN patients that underwent surgery (2004-2015). Patients in the lowest quartile of travel distance and volume (Short-travel/Low-Volume: STLV) were compared to patients in the highest quartile of travel distance and volume (Long-travel/High-Volume: LTHV). Only STLV and LTHV cases were included for analysis. RESULTS: Of 13,370 cases, 2,408 met inclusion criteria. STLV patients (n = 1,305) traveled a median of 6 miles (Interquartile range [IQR] 3-9) to low-volume centers (median 2, IQR 1-3 annual cases) and LTHV patients (n = 1,103) traveled a median of 143 miles [IQR 103-230, maximum 4,797] to high-volume centers (median 34, IQR 28-42 annual cases). LTHV patients had lower Charlson/Deyo scores (p = 0.001), mostly received care at academic centers (81.7% vs. 39.4%, p < 0.001), and were less likely to be minorities (7.0% vs. 24.2%, p < 0.001) or underinsured (4.2% vs. 13.8%, p < 0.001). There was no difference in average tumor size. On multivariable analysis, LTHV predicted increased likelihood of gross total resection (odds ratio [OR] 5.6, 95% confidence interval [CI] 3.8-8.4, p < 0.001), longer duration between diagnosis and surgery (OR 1.3, 95% CI 1.0-1.6, p = 0.040), decreased length of hospital stay (OR 0.5, 95% CI 0.4-0.7, p < 0.001), and greater overall survival (Hazard Ratio [HR] 0.6, 95% CI 0.4-0.95, p = 0.029). There was no significant difference in 30-day readmission on adjusted analysis. CONCLUSION: Although traveling farther to high-volume centers was associated with greater time between diagnosis and treatment for AN patients, they experienced superior postoperative outcomes compared to patients who received treatment locally at low-volume centers. Enabling access and travel to high-volume centers may improve AN patient outcomes.

Prognostic factors in diffuse leptomeningeal glioneuronal tumor (DLGNT): a systematic review.

BACKGROUND: Diffuse leptomeningeal glioneuronal tumor (DLGNT) is a rare tumor, first described by the WHO Classification of Central Nervous System Tumors in 2016. The clinical course is variable. Most tumors have low-grade histological findings although some may have more aggressive features. The goal of this systematic review was to identify prognostic factors for poor overall survival (OS). MATERIAL AND METHODS: We performed a systematic review using three databases (PubMed, Google Scholar, and Embase) and the following search terms: diffuse leptomeningeal glioneuronal tumor, DLGNT, DLMGNT. Statistical analysis was performed using Statistica 13.3. RESULTS: We included 34 reports in our review comprising 63 patients, published from 2016 to 2022. The median OS was 19 months (range: 12-51 months). Using multivariable Cox survival analysis, we showed that Ki-67 ≥ 7%, age > 9 years, symptoms of elevated intracranial pressure (ICP) at admission, and the presence of contrast-enhancing intraparenchymal tumor are associated with poor OS. Receiver operating characteristic (ROC) analysis identified Ki-67 ≥ 7% as a significant predictor of poor OS. CONCLUSIONS: Signs or symptoms of increased ICP with imaging findings of diffuse leptomeningeal enhancement should raise suspicion for DLGNT. In our systematic review, Ki-67 ≥ 7% was the most important prognostic factor for OS in DLGNT. The presence of intraparenchymal tumor with contrast enhancement was thought to represent disease progression and, together with patient age, was associated with poor OS.

Application of Antibiotic-Impregnated Polymethyl-Methacrylate Bone Cement for the Treatment of Infected Cranioplasties: Initial Experience.

BACKGROUND: Management of infected cranioplasty implants remains a surgical challenge. Surgical debridement, removal of the infected implant, and prolonged antibiotic therapy are part of the acute management. In addition, cranioplasty removal poses the risk of dural tear. Reconstruction of the cranial defect is usually delayed for several months to years, increasing the difficulty due to soft tissue contraction and scarring. OBJECTIVE: The aim of the study was to propose an alternative to delayed reconstruction in the face of infection with a dual purpose: treat the infection with a material which delivers antibiotic to the area (polymethyl-methacrylate antibiotic) and which functions as a temporary or permanent cranioplasty. METHODS: We reviewed the records of 3 consecutive patients who underwent single-stage polymethyl-methacrylate antibiotic salvage cranioplasty. RESULTS: All patients underwent debridement of infected tissue. Titanium mesh was placed over the bony defect. Polymethyl methacrylate impregnated with vancomycin and tobramycin was then spread over the plate and defect before closure. Patients also received extended treatment with systemic antimicrobials. Early outcomes have been encouraging for both cosmesis and treatment of infection. CONCLUSIONS: Benefits of this treatment strategy include immediate reconstruction rather than staged procedures and delivery of high concentrations of antibiotics directly to the affected area in addition to systemic antibiotics.

Arteriovenous malformation surgery in children: the Rady Children's Hospital experience (2002-2019).

PURPOSE: Compared to adult AVMs, there is a paucity of data on the microsurgical treatment of pediatric AVMs. We report our institutional experience with pediatric AVMs treated by microsurgical resection with or without endovascular embolization and radiation therapy. METHODS: We retrospectively reviewed all patients ≤ 18 years of age with cerebral AVMs that underwent microsurgical resection at Rady Children's Hospital 2002-2019. RESULTS: Eighty-nine patients met inclusion criteria. The mean age was 10.3 ± 5.0 years, and 56% of patients were male. In total, 72 (81%) patients presented with rupture. Patients with unruptured AVMs presented with headache (n = 5, 29.4%), seizure (n = 9, 52.9%), or incidental finding (n = 3, 17.7%). The mean presenting mRS was 2.8 ± 1.8. AVM location was lobar in 78%, cerebellar/brainstem in 15%, and deep supratentorial in 8%. Spetzler-Martin grade was I in 28%, II in 45%, III in 20%, IV in 6%, and V in 1%. Preoperative embolization was utilized in 38% of patients and more frequently in unruptured than ruptured AVMs (62% vs. 32%, p = 0.022). Radiographic obliteration was achieved in 76/89 (85.4%) patients. Complications occurred in 7 (8%) patients. Annualized rates of delayed rebleeding and recurrence were 1.2% and 0.9%, respectively. The mean follow-up was 2.8 ± 3.1 years. A good neurological outcome (mRS score ≤ 2) was obtained in 80.9% of patients at last follow-up and was improved relative to presentation for 75% of patients. CONCLUSIONS: Our case series demonstrates high rates of radiographic obliteration and relatively low incidence of neurologic complications of treatment or AVM recurrence.

Analysis of Actual Versus Predicated Intracranial Volume Changes for Distraction Osteogenesis Using Virtual Surgical Planning in Patients With Craniosynostosis.

INTRODUCTION: The primary outcome metric in patients with craniosynostosis are changes in intracranial volumes (ICVs). In patients who undergo distraction osteogenesis (DO) to treat craniosynostosis, changes are also dependent on the length of distraction. Virtual surgical planning (VSP) has been used to predict anticipated changes in ICV during cranial vault reconstruction. The purpose of this study is to analyze the actual versus predicted ICV changes using VSP in patients who undergo DO for craniosynostosis management. METHODS: All patients with craniosynostosis treated with DO at a single institution, Rady Children's Hospital, between December 2013 and May 2019 were identified. Inclusion criteria are as follows: VSP planning with predicted postoperative ICV values and preoperative and postdistraction CT scans to quantify ICV. Postoperative ICV and VSP-estimated ICV were adjusted for age-related ICV growth. The primary outcome measure calculated was age-adjusted percent volume change per millimeter distraction (PVCPD), and results were analyzed using paired Wilcoxon signed rank tests. RESULTS: Twenty-seven patients underwent DO for cranial vault remodeling. Nineteen patients were nonsyndromic, and 8 patients were syndromic. The median postoperative PVCPD was 0.30%/mm, and the median VSP-estimated PVCPD was 0.36% per millimeter (P < 0.001). A subanalysis of nonsyndromic patients showed a median postoperative PVCPD of 0.29%/mm in nonsyndromic patients that differed significantly from the VSP estimate of 0.34%/mm (P = 0.003). There was also a significant difference in syndromic patients' observed PVCPD of 0.41%/mm versus VSP estimate of 0.79%/mm (P = 0.012). CONCLUSIONS: Virtual surgical planning overestimates the change in ICV attributable to DO in both syndromic and nonsyndromic patients.

Quality of care at safety-net hospitals and the impact on pay-for-performance reimbursement.

BACKGROUND: Pay-for-performance reimbursement ties hospital payments to standardized quality-of-care metrics. To the authors' knowledge, the impact of pay-for-performance reimbursement models on hospitals caring primarily for uninsured or underinsured patients remains poorly defined. The objective of the current study was to evaluate how standardized quality-of-care metrics vary by a hospital's propensity to care for uninsured or underinsured patients and demonstrate the potential impact that pay-for-performance reimbursement could have on hospitals caring for the underserved. METHODS: The authors identified 1,703,865 patients with cancer who were diagnosed between 2004 and 2015 and treated at 1344 hospitals. Hospital safety-net burden was defined as the percentage of uninsured or Medicaid patients cared for by that hospital, categorizing hospitals into low-burden, medium-burden, and high-burden hospitals. The authors evaluated the impact of safety-net burden on concordance with 20 standardized quality-of-care measures, adjusting for differences in patient age, sex, stage of disease at diagnosis, and comorbidity. RESULTS: Patients who were treated at high-burden hospitals were more likely to be young, male, Black and/or Hispanic, and to reside in a low-income and low-educated region. High-burden hospitals had lower adherence to 13 of 20 quality measures compared with low-burden hospitals (all P < .05). Among the 350 high-burden hospitals, concordance with quality measures was found to be lowest for those caring for the highest percentage of uninsured or Medicaid patients, minority patients, and less educated patients (all P < .001). CONCLUSIONS: Hospitals caring for uninsured or underinsured individuals have decreased quality-of-care measures. Under pay-for-performance reimbursement models, these lower quality-of-care scores could decrease hospital payments, potentially increasing health disparities for at-risk patients with cancer.

Probing the lithium-response pathway in hiPSCs implicates the phosphoregulatory set-point for a cytoskeletal modulator in bipolar pathogenesis.

The molecular pathogenesis of bipolar disorder (BPD) is poorly understood. Using human-induced pluripotent stem cells (hiPSCs) to unravel such mechanisms in polygenic diseases is generally challenging. However, hiPSCs from BPD patients responsive to lithium offered unique opportunities to discern lithium's target and hence gain molecular insight into BPD. By profiling the proteomics of BDP-hiPSC-derived neurons, we found that lithium alters the phosphorylation state of collapsin response mediator protein-2 (CRMP2). Active nonphosphorylated CRMP2, which binds cytoskeleton, is present throughout the neuron; inactive phosphorylated CRMP2, which dissociates from cytoskeleton, exits dendritic spines. CRMP2 elimination yields aberrant dendritogenesis with diminished spine density and lost lithium responsiveness (LiR). The "set-point" for the ratio of pCRMP2:CRMP2 is elevated uniquely in hiPSC-derived neurons from LiR BPD patients, but not with other psychiatric (including lithium-nonresponsive BPD) and neurological disorders. Lithium (and other pathway modulators) lowers pCRMP2, increasing spine area and density. Human BPD brains show similarly elevated ratios and diminished spine densities; lithium therapy normalizes the ratios and spines. Consistent with such "spine-opathies," human LiR BPD neurons with abnormal ratios evince abnormally steep slopes for calcium flux; lithium normalizes both. Behaviorally, transgenic mice that reproduce lithium's postulated site-of-action in dephosphorylating CRMP2 emulate LiR in BPD. These data suggest that the "lithium response pathway" in BPD governs CRMP2's phosphorylation, which regulates cytoskeletal organization, particularly in spines, modulating neural networks. Aberrations in the posttranslational regulation of this developmentally critical molecule may underlie LiR BPD pathogenesis. Instructively, examining the proteomic profile in hiPSCs of a functional agent-even one whose mechanism-of-action is unknown-might reveal otherwise inscrutable intracellular pathogenic pathways.

Detailed analysis of the impact of surgeon and hospital volume in microsurgical breast reconstruction.

BACKGROUND: Prior investigations of microsurgical breast reconstruction have not distinguished the effects of surgeon versus hospital volume and failed to address the effect of patient clustering. Our data-driven analysis aims to determine the impacts of surgeon and hospital volume on outcomes of microsurgical breast reconstruction. METHODS: Nationwide Inpatient Sample (NIS) data from 2008 to 2011 was analyzed for patients who underwent microsurgical breast reconstruction. Volume-outcome relationships were analyzed with restricted cubic spline analysis. A multivariable mixed-effects logistic regression was used to account for patient clustering effect. RESULTS: A total of 5,404 NIS patients met inclusion criteria. High-volume (HV) surgeons had a 59% decrease in the risk of inpatient complications, which became non-significant after clustering correction. For HV hospitals, there was a 47% decrease in the risk of inpatient complications (odds ratio = 0.53; 95% confidence intervals 0.30, 0.91; p = 0.021) that was statistically significant with the clustering adjustment. Neither the volume-cost relationship for surgeons nor hospitals remained statistically significant after accounting for clustering. CONCLUSIONS: Hospital volume plays a significant impact on outcomes in microsurgical breast reconstruction, while surgeon volume has comparatively not shown to be similarly impactful. The complexity of care related to microsurgical breast reconstruction warrants equally complex and engineered health systems.

A Comparison of Intracranial Volume Growth in Normal Children and Patients With Metopic Craniosynostosis.

BACKGROUND: The impact of metopic craniosynostosis on intracranial volume (ICV) and ICV growth is unclear. In addition, the relationship between head circumference (HC) and ICV in these patients is not previously described. METHODS: A retrospective review of 72 patients with metopic craniosynostosis was performed. The ICVs were calculated from manually segmented preoperative computed tomography scans. Magnetic resonance imaging data for 270 healthy children were available. The ICVs were calculated in FreeSurfer.First, a growth curve for metopic patients was generated and a logarithmic best-fit curve was calculated. Second, the impact of metopic craniosynostosis on ICV relative to healthy controls was assessed using multivariate linear regression. Third, the growth curves for metopic patients and healthy children were compared.Pearson's correlation was used to measure the association between HC and ICV. RESULTS: Mean metopic ICV was significantly lower than normal ICV within the first 3 to 6 months (674.9 versus 813.2 cm; P = 0.002), 6 to 9 months (646.6 versus 903.9 cm; P = 0.005), and 9 to 12 months of life (848.0 versus 956.6 cm; P = 0.038). There was no difference in ICV after 12 months of age (P = 0.916).The ICV growth in patients with metopic craniosynostosis is defined by a significantly different growth curve than in normal children (P = 0.005).The ICV and HC were highly correlated across a broad range of ICVs and patient age (r = 0.98, P < 0.001). CONCLUSION: Patients with metopic craniosynostosis have significantly reduced ICVs compared to healthy children, yet greater than normal ICV growth, which allows them to achieve normal volumes by 1 year of age. The HC is a reliable metric for ICV in these patients.

Cost-effectiveness of Intraoperative MRI for Treatment of High-Grade Gliomas.

Background Intraoperative MRI has been shown to improve gross-total resection of high-grade glioma. However, to the knowledge of the authors, the cost-effectiveness of intraoperative MRI has not been established. Purpose To construct a clinical decision analysis model for assessing intraoperative MRI in the treatment of high-grade glioma. Materials and Methods An integrated five-state microsimulation model was constructed to follow patients with high-grade glioma. One-hundred-thousand patients treated with intraoperative MRI were compared with 100 000 patients who were treated without intraoperative MRI from initial resection and debulking until death (median age at initial resection, 55 years). After the operation and treatment of complications, patients existed in one of three health states: progression-free survival (PFS), progressive disease, or dead. Patients with recurrence were offered up to two repeated resections. PFS, valuation of health states (utility values), probabilities, and costs were obtained from randomized controlled trials whenever possible. Otherwise, national databases, registries, and nonrandomized trials were used. Uncertainty in model inputs was assessed by using deterministic and probabilistic sensitivity analyses. A health care perspective was used for this analysis. A willingness-to-pay threshold of $100 000 per quality-adjusted life year (QALY) gained was used to determine cost efficacy. Results Intraoperative MRI yielded an incremental benefit of 0.18 QALYs (1.34 QALYs with intraoperative MRI vs 1.16 QALYs without) at an incremental cost of $13 447 ($176 460 with intraoperative MRI vs $163 013 without) in microsimulation modeling, resulting in an incremental cost-effectiveness ratio of $76 442 per QALY. Because of parameter distributions, probabilistic sensitivity analysis demonstrated that intraoperative MRI had a 99.5% chance of cost-effectiveness at a willingness-to-pay threshold of $100 000 per QALY. Conclusion Intraoperative MRI is likely to be a cost-effective modality in the treatment of high-grade glioma. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Bettmann in this issue.

The impact of traveling distance and hospital volume on post-surgical outcomes for patients with glioblastoma.

BACKGROUND: High-volume hospitals are associated with improved outcomes in glioblastoma (GBM). However, the impact of travel burden to high-volume centers is poorly understood. We examined post-operative outcomes between GBM patients that underwent treatment at local, low-volume hospitals with those that traveled long distances to high-volume hospitals. METHODS: The National Cancer Database was queried for GBM patients that underwent surgery (2010-2014). We established two cohorts: patients in the lowest quartile of travel distance and volume (Short-travel/Low-Volume: STLV) and patients in the highest quartile of travel and volume (Long-travel/High-Volume: LTHV). Outcomes analyzed were 30-day, 90-day mortality, overall survival, 30-day readmission, and hospital length of stay. RESULTS: Of 35,529 cases, STLV patients (n = 3414) traveled a median of 3 miles (Interquartile range [IQR] 1.8-4.2) to low-volume centers (5 [3-7] annual cases) and LTHV patients (n = 3808) traveled a median of 62 miles [44.1-111.3] to high-volume centers (48 [42-71]). LTHV patients were younger, had lower Charlson scores, largely received care at academic centers (84.4% vs 11.9%), were less likely to be minorities (8.1% vs 17.1%) or underinsured (6.9% vs 12.1), and were more likely to receive trimodality therapy (75.6% vs 69.2%; all p < 0.001). On adjusted analysis, LTHV predicted improved overall survival (HR 0.87, p = 0.002), decreased 90-day mortality (OR 0.72, p = 0.019), lower 30-day readmission (OR 0.42, p < 0.001), and shorter hospitalizations (RR 0.79, p < 0.001). CONCLUSIONS: Glioblastoma patients who travel farther to high-volume centers have superior post-operative outcomes compared to patients who receive treatment locally at low-volume centers. Strategies that facilitate patient travel to high-volume hospitals may improve outcomes.

The Cost to Attending Surgeons of Resident Involvement in Academic Hand Surgery.

PURPOSE: For many types of surgical cases, there is an increase in length with the participation of a resident physician. The lost operative time productivity is not necessarily mitigated in any fashion other than to benefit the experience of the trainee. Moreover, increasing pressures to maximize productivity, coupled with diminishing reimbursements serve to disincentive resident involvement. The aim of this study was to examine the opportunity cost in the academic setting for intraoperative resident participation during specific hand surgery cases. METHODS: Retrospective analysis was performed on the American College of Surgeons National Surgical Quality Improvement Project (NSQIP) database from 2006 to 2015. Cases were identified by Current Procedural Terminology code to isolate distal radius fracture repairs, carpal tunnel releases, scaphoid fractures repairs, and metacarpal fracture repairs. Variables collected included operation time, presence or absence of resident physician, and postgraduate year level. Statistical analysis was performed using the statistical computing software R 3.4.2 (R Foundation for Statistical Computing, Vienna, Austria). Cost analysis was performed to quantify the effect of operative times in terms of relative value units (RVUs) lost. RESULTS: A total of 3727 cases were identified. Of those, 1264 cases were performed with a resident present. Residents participated in cases with higher total RVU (14.91 vs 13.16, P < 0.001). There was a statistically significant increase of 24.3 minutes (P < 0.001) in the mean operation time with a resident present as compared with those without. Moreover, RVU per hour in resident cases was significantly lower by 2.97 RVU per hour or 21% (P < 0.001). Using the late 2018 Medicare physician conversion factor of US $33.9996, the opportunity cost to attending physicians is US $159.20 per case. CONCLUSIONS: Resident participation in surgical cases is paramount to the education of future trainees, particularly in the era of trainee duty hour reform. Because residents are participating in higher total RVU cases, this selection bias may be playing a role in explaining our result. Nonetheless, resident involvement for certain procedures comes at an opportunity cost to faculty surgeons. How to balance the cost to train residents in the emerging value-based health systems will prove to be challenging but requires consideration.

A Study to Evaluate Change in Ventricular Volume Obtained by Cranial Distraction for Craniosynostosis.

BACKGROUND: The aims of the current analysis were to study the change in ventricular volume (VV) obtained with cranial distraction in patients with craniosynostosis and compare it with the change in total intracranial volume (ICV) and brain volume. METHODS: After institutional review board approval, a retrospective review was performed on patients undergoing cranial distraction over a 5-year period. GE Healthcare AdW 4.3 volume assessment software was utilized to calculate preoperative and postdistraction ICV, VV, and whole-brain volume. Data were also collected on patient demographics, age at the time of distraction, time spent in distraction and consolidation, and length of stay. t Tests were used for comparison. RESULTS: Twenty-three patients met our inclusion criteria. Forty-eight percent of patients (n = 11) had right-sided cranial distraction, 30% (n = 7) had bilateral distraction, and 22% of patients (n = 5) had left-sided distraction. At the preoperative stage, mean head circumference was 42.5 ± 4.7 cm, mean ICV was 810.1 ± 27 cm, mean non-VV (NVV) was 796.2 ± 268 cm, and mean VV was 13.9 ± 9 cm. After a mean of 27.4 mm of distraction, occurring over a mean of 26 days and consolidation period of 149 days, a second computed tomography scan was obtained. Mean postdistraction head circumference was 49.1 ± 3.9 cm, mean ICV was 1074.1 ± 203 cm, mean NVV was 1053.5 ± 197 cm, and VV was 20.6 ± 14 cm. Mean % increase in ICV at this stage was 47.4%; mean % NVV increase was 48.5% as opposed to 60.3% increase in VV. CONCLUSIONS: Cranial distraction is known to effectively increase ICV. Our study suggests that the effect of this volumetric increase is much more pronounced on the VV compared with the brain volume. Further studies are underway to investigate whether this short-term marked increase in VV is sustained over a long-term period.

Can Head Circumference Be Used as a Proxy for Intracranial Volume in Patients With Craniosynostosis?

BACKGROUND: Calculation of intracranial volume from neuroimaging can be complex and time consuming. In the adult population, there is evidence suggesting that owing to its strong correlation, head circumference (HC) may be used as a surrogate for intracranial volume (ICV). We were interested in studying the correlation between HC and ICV in patients with craniosynostosis. METHODS: After institutional review board approval, a retrospective review was performed on patients with craniosynostosis. GE Healthcare AdW 4.3 volume assessment software was used to calculate ICV and HC based on preoperative computed tomographic scans. Pearson correlation was used to estimate correlation coefficients between ICV and HC for this patient population, with 0 to 0.3 considered a weak correlation, 0.4 to 0.6 considered a moderate correlation, 0.7 to 1 considered a strong correlation, and P < 0.05 was considered statistically significant. RESULTS: A total of 196 craniosynostosis patients were included in this study. There were 121 male and 75 female patients. Seventy-nine patients had metopic, 45 had coronal, 64 had sagittal, and 8 had lambdoid synostosis. Mean age was 8.2 months. Mean HC and ICV were 42.9 cm and 829 cm, respectively. Overall, there was a strong correlation between HC and ICV (r = 0.81). Patients were further categorized by craniosynostosis type. Very strong correlation was obtained for patients with coronal (0.89), metopic (0.98), and lambdoid craniosynostosis (0.97). Strong correlation was obtained for patients with sagittal synostosis (0.73). When categorized by sex, a stronger correlation was obtained for female patients (0.84) compared with male patients (0.80). Statistical significance was reached for all reported correlations. CONCLUSION: Our preliminary data suggest that a very strong correlation exists between HC and ICV for male and female patients with all types of craniosynostosis, making HC a useful surrogate for ICV in this patient population.

Management of glioblastoma at safety-net hospitals.

BACKGROUND: Safety-net hospitals (SNHs) provide disproportionate care for underserved patients. Prior studies have identified poor outcomes, increased costs, and reduced access to certain complex, elective surgeries at SNHs. However, it is unknown whether similar patterns exist for the management of glioblastoma (GBM). We sought to determine if patients treated at HBHs receive equitable care for GBM, and if safety-net burden status impacts post-treatment survival. METHODS: The National Cancer Database was queried for GBM patients diagnosed between 2010 and 2015. Safety-net burden was defined as the proportion of Medicaid and uninsured patients treated at each hospital, and stratified as low (LBH), medium (MBH), and high-burden (HBH) hospitals. The impact of safety-net burden on the receipt of any treatment, trimodality therapy, gross total resection (GTR), radiation, or chemotherapy was investigated. Secondary outcomes included post-treatment 30-day mortality, 90-day mortality, and overall survival. Univariate and multivariate analyses were utilized. RESULTS: Overall, 40,082 GBM patients at 1202 hospitals (352 LBHs, 553 MBHs, and 297 HBHs) were identified. Patients treated at HBHs were significantly less likely to receive trimodality therapy (OR = 0.75, p < 0.001), GTR (OR = 0.84, p < 0.001), radiation (OR = 0.73, p < 0.001), and chemotherapy (OR = 0.78, p < 0.001) than those treated at LBHs. Patients treated at HBHs had significantly increased 30-day (OR = 1.25, p = 0.031) and 90-day mortality (OR = 1.24, p = 0.001), and reduced overall survival (HR = 1.05, p = 0.039). CONCLUSIONS: GBM patients treated at SNHs are less likely to receive standard-of-care therapies and have increased short- and long-term mortality. Additional research is needed to evaluate barriers to providing equitable care for GBM patients at SNHs.

Markov modeling for the neurosurgeon: a review of the literature and an introduction to cost-effectiveness research.

OBJECTIVE Markov modeling is a clinical research technique that allows competing medical strategies to be mathematically assessed in order to identify the optimal allocation of health care resources. The authors present a review of the recently published neurosurgical literature that employs Markov modeling and provide a conceptual framework with which to evaluate, critique, and apply the findings generated from health economics research. METHODS The PubMed online database was searched to identify neurosurgical literature published from January 2010 to December 2017 that had utilized Markov modeling for neurosurgical cost-effectiveness studies. Included articles were then assessed with regard to year of publication, subspecialty of neurosurgery, decision analytical techniques utilized, and source information for model inputs. RESULTS A total of 55 articles utilizing Markov models were identified across a broad range of neurosurgical subspecialties. Sixty-five percent of the papers were published within the past 3 years alone. The majority of models derived health transition probabilities, health utilities, and cost information from previously published studies or publicly available information. Only 62% of the studies incorporated indirect costs. Ninety-three percent of the studies performed a 1-way or 2-way sensitivity analysis, and 67% performed a probabilistic sensitivity analysis. A review of the conceptual framework of Markov modeling and an explanation of the different terminology and methodology are provided. CONCLUSIONS As neurosurgeons continue to innovate and identify novel treatment strategies for patients, Markov modeling will allow for better characterization of the impact of these interventions on a patient and societal level. The aim of this work is to equip the neurosurgical readership with the tools to better understand, critique, and apply findings produced from cost-effectiveness research.