Anterior versus Posterior Ventricular Catheter Placement in Pediatric Patients: A Systematic Review and Meta-Analysis.

BACKGROUND: Ventriculoperitoneal shunt placement is the mainstay of treatment for hydrocephalus, but there are relatively high rates of malfunction. Shunt catheter entry can be performed anteriorly or posteriorly, with the body of evidence from randomized controlled trials and retrospective studies suggesting conflicting findings. METHODS: A systematic review of PubMed, Medline, Scopus, and Web of Science was performed adherent to PRISMA guidelines, searching for clinical studies examining outcomes for anterior or frontal and posterior or occipital ventriculoperitoneal shunt placement. A random-effects model meta-analysis was performed on R. RESULTS: Six studies (2 randomized controlled trials and 4 retrospective cohort studies) comprising 1808 patients were identified. There were no statistically significant differences between anterior and posterior ventriculoperitoneal shunt placement for the outcomes of poor catheter placement (odds ratio [OR], 0.74; P = 0.6) and shunt infections (OR, 1.01; P = 0.9). Posterior shunts trended toward greater number of shunt revisions (OR, 0.72; P = 0.06). Six and 12 months shunt survival was comparable between anterior and posterior approaches (P > 0.05). There were significant differences between long-term shunt survival (2 and 5 years shunt survival), favoring anterior shunt placement with greater odds of survival (OR, 1.91 and OR, 1.62, respectively; P < 0.05). CONCLUSIONS: We show that although anteriorly and posteriorly placed shunts have mostly comparable outcomes, shunt survival at 2-year and 5-year intervals favors anteriorly placed shunts. Additional well-designed clinical trials are needed to validate the findings of greater late shunt failure in posteriorly placed shunts, with more time-dependent statistical measures.

Initial Clinical Experience With ClearPoint SmartFrame Array-Aided Stereotactic Procedures.

BACKGROUND: The ClearPoint SmartFrame Array (ClearPoint Neuro, Inc., Solana Beach, CA) system consists of a magnetic resonance imaging compatible frame supported by a customized neuro navigation software. This system received U.S. Food and Drug Administrationclearance for clinical use in January 2021. Our objective was to report initial safety data and user experience of SmartFrame Array-supported stereotactic procedures. METHODS: We prospectively followed the first 10 consecutive patients who underwent stereotactic procedures supported by SmartFrame Array. Clinical and procedural data were recorded and compared to data obtained from prior cases with SmartFrame XG. RESULTS: Ten patients underwent stereotactic needle biopsy, stereotactic laser ablation (SLA), or combined biopsy/SLA procedures. For needle biopsies (n = 9), the average maximal diameter of the contrast-enhancing target lesion was 9.9 ± 2.8 mm. The radial error of stereotaxis was less than 2 mm. Definitive diagnosis was achieved in all cases. For procedures involving SLA (n = 5), 100% of the contrast-enhancing lesion was ablated. All patients were discharged home by postoperative day 2. There were no 30-day readmissions, morbidity, or mortality. The average stereotaxis time for the SmartFrame Array-aided single trajectory procedure was 80 ± 9.5 minutes, which compared favorably to that required for the earlier generation SmartFrame XG frame (111.5 ± 16.5 minutes; P < 0.01). The unique Array design supported stereotactic procedures that cannot be easily achieved with the previous SmartFrame XG frame. CONCLUSIONS: The SmartFrame Array system offers a more rigid and compact build to enhance procedural efficiency while maintaining accuracy and safety. The design supports multi-trajectory stereotaxis, allowing novel clinical applications.

Learning Curve Associated with ClearPoint Neuronavigation System: A Case Series.

BACKGROUND: The ClearPoint neuronavigation system affords real-time magnetic resonance imaging (MRI) guidance during stereotactic procedures. While such information confers potential clinical benefits, additional operative time may be needed. METHODS: We conducted a retrospective analysis of procedural time associated with ClearPoint Stereotaxis, with hypothesis that this procedural time is comparable with that associated with frame-based biopsy. RESULTS: Of the 52 patients evaluated, the total procedural time for ClearPoint stereotactic biopsy averaged 150.0 (±40.4) minutes, of which 111.5 (±16.5) minutes were dedicated to real-time MRI acquisition and trajectory adjustment. This procedural time is within the range of those reported for frame-based needle biopsies. Approximately 5 minutes of the procedural time is related to the mounting of the MRI-compatible stereotactic frame. Based on the procedural time, we estimate that four cases are required in the learning curve to achieve this efficiency. Efficient algorithms for distortion corrections and isocenter localization are keys to ClearPoint stereotaxis. Routine quality assurance/control after each MRI software update and institutional information technology maintenance also contribute to efficiency. Real-time MRI is essential for definitive diagnosis in select cases. CONCLUSIONS: ClearPoint stereotactic needle biopsy can be achieved in time frames comparable to frame-based stereotaxis. However, procedural efficiency requires 4 "learning curve" cases as well as vigilance in terms of MR distortion correction and information technology maintenance.

Potential and limitations of radiomics in neuro-oncology.

Radiomics seeks to apply classical methods of image processing to obtain quantitative parameters from imaging. Derived features are subsequently fed into algorithmic models to aid clinical decision making. The application of radiomics and machine learning techniques to clinical medicine remains in its infancy. The great potential of radiomics lies in its objective, granular approach to investigating clinical imaging. In neuro-oncology, advanced machine learning techniques, particularly deep learning, are at the forefront of new discoveries in the field. However, despite the great promise of machine learning aided radiomic approaches, the current use remains confined to scholarly research, without real-world deployment in neuro-oncology. The paucity of data, inconsistencies in preprocessing, radiomic feature instability, and the rarity of the events of interest are critical barriers to clinical translation. In this article, we will outline the major steps in the process of radiomics, as well as review advances and challenges in the field as they pertain to neuro-oncology.

Online Reviews of Hemodialysis Centers Correlate With Medicare and Medicaid Survey Measures of Patient Experience.

BACKGROUND AND OBJECTIVES: Patient experience in outpatient hemodialysis has been shown to be significantly correlated with health outcomes. The current gold standard for assessing patient experience in outpatient hemodialysis is the In-Center Hemodialysis Consumer Assessment of Healthcare Providers and Systems (ICH-CAHPS). Online reviews of outpatient hemodialysis centers could potentially serve as an additional source of information regarding patient experience, but they have not been well validated. This study aims to determine whether overall scores and subscores from patient-authored online reviews of outpatient dialysis centers are correlated with current gold standard survey-based measures of patient experience in outpatient hemodialysis. METHODS: All reviews of hemodialysis centers posted to the online review site CiteHealth.com between March 2008 and October 2019 were collected (1081 reviews of 762 centers). Publicly-available ICH-CAHPS survey summary data and End Stage Renal Disease Quality Incentive Program (ESRD QIP) summary data from May 2016 to October 2019 were obtained from the Dialysis Facility Compare website. Spearman correlation coefficients were calculated between facilities' mean online review overall scores and subscores within a given year and their ICH-CAHPS ratings from the same year. Statistical significance was assessed with a 2-tailed permutation test. A Bonferroni correction for multiple hypothesis testing was applied. RESULTS: The mean "Overall" score from CiteHealth.com had a significant positive correlation with the "Center Care Quality," "Staff," and "Facility" scores from ICH-CAHPS surveys. No significant correlation could be found between the mean "Overall" CiteHealth.com score and any other ICH-CAHPS patient satisfaction metric. There was a significant positive correlation between the mean CiteHealth.com "Center" score and the ICH-CAHPS "Center Care Quality" score, the mean CiteHealth.com "Facility" score and the ICH-CAHPS "Facility" score, and the mean CiteHealth.com "Staff" score and the ICH-CAHPS "Staff" score. No significant correlation was found between the mean CiteHealth.com "Nephrologist" score and the ICH-CAHPS "Nephrologist" score. No significant correlation was found between online review scores and ESRD QIP health outcome measures. CONCLUSION: Certain components of online reviews are significantly correlated with ICH-CAHPS measures of patient experience. Additionally, online reviews come with narrative comments that can offer specific insights into positive and negative aspects of patient care that cannot always be elucidated by numeric survey questions. Online reviews may have utility as an adjunctive source of information to patient experience surveys such as the ICH-CAHPS.

Detection of Isocitrate Dehydrogenase Mutated Glioblastomas Through Anomaly Detection Analytics.

BACKGROUND: The rarity of Isocitrate Dehydrogenase mutated (mIDH) glioblastomas relative to wild-type IDH glioblastomas, as well as their distinct tumor physiology, effectively render them "outliers". Specialized tools are needed to identify these outliers. OBJECTIVE: To carefully craft and apply anomaly detection methods to identify mIDH glioblastoma based on radiomic features derived from magnetic resonance imaging. METHODS: T1-post gadolinium images for 188 patients and 138 patients were downloaded from The Cancer Imaging Archive's (TCIA) The Cancer Genome Atlas (TCGA) glioblastoma collection, and from the University of Minnesota Medical Center (UMMC), respectively. Anomaly detection methods were tested on glioblastoma image features for the precision of mIDH detection and compared to standard classification methods. RESULTS: Using anomaly detection training methods, we were able to detect IDH mutations from features in noncontrast-enhancing regions in glioblastoma with an average precision of 75.0%, 69.9%, and 69.8% using three different models. Anomaly detection methods consistently outperformed traditional two-class classification methods from 2 unique learning models (67.9%, 67.6%). The disparity in performances could not be overcome through newer, popular models such as neural networks (67.4%). CONCLUSION: We employed an anomaly detection strategy in the detection of IDH mutation in glioblastoma using preoperative T1 postcontrast imaging. We show these methods outperform traditional two-class classification in the setting of dataset imbalances inherent to IDH mutation prevalence in glioblastoma. We validate our results using an external dataset and highlight new possible avenues for radiogenomic rare event prediction in glioblastoma and beyond.

State of Radiomics in Glioblastoma.

Radiomics is an emerging discipline that aims to make intelligent predictions and derive medical insights based on quantitative features extracted from medical images as a means to improve clinical diagnosis or outcome. Pertaining to glioblastoma, radiomics has provided powerful, noninvasive tools for gaining insights into pathogenesis and therapeutic responses. Radiomic studies have yielded meaningful biological understandings of imaging features that are often taken for granted in clinical medicine, including contrast enhancement on glioblastoma magnetic resonance imaging, the distance of a tumor from the subventricular zone, and the extent of mass effect. They have also laid the groundwork for noninvasive detection of mutations and epigenetic events that influence clinical outcomes such as isocitrate dehydrogenase (IDH) and O6-methylguanine-DNA methyltransferase (MGMT). In this article, we review advances in the field of glioblastoma radiomics as they pertain to prediction of IDH mutation status and MGMT promoter methylation status, as well as the development of novel, higher order radiomic parameters.

Increases in female academic productivity and female mentorship highlight sustained progress in previously identified neurosurgical gender disparities.

OBJECTIVE: A meta-analysis was performed to understand disparities in the representation of female authorship within the neurosurgical literature and implications for career advancement of women in neurosurgery. METHODS: Author names for articles published in 16 of the top neurosurgical journals from 2002 to 2019 were obtained from MEDLINE. The gender of each author was determined using automated prediction methods. Publication trends were compared over time and across subdisciplines. Female authorship was also compared to the proportionate composition of women in the field over time. RESULTS: The metadata obtained from 16 major neurosurgical journals yielded 66,546 research articles. Gender was successfully determined for 96% (127,809/133,578) of first and senior authors, while the remainder (3.9%) were unable to be determined through prediction methods. Across all years, 13.3% (8826) of articles had female first authorship and 9.1% (6073) had female senior authorship. Female first authorship increased significantly over time from 5.8% in 2002 to 17.2% in 2019 (p < 0.001). Female senior authorship also increased significantly over time, from 5.5% in 2002 to 12.0% in 2019 (p < 0.001). The journals with the highest proportions of female first authors and senior authors were the Journal of Neurosurgery: Pediatrics (33.5%) and the Asian Journal of Neurosurgery (23.8%), respectively. Operative Neurosurgery had the lowest fraction of female first (12.4%) and senior (4.7%) authors. There was a significant difference between the year-by-year proportion of female neurosurgical trainees and the year-by-year proportion of female neurosurgical first (p < 0.001) and senior (p < 0.001) authors. Articles were also more likely to have a female first author if the senior author of the article was female (OR 2.69, CI 2.52-2.86; p < 0.001). From 1944 to 2019, the Journal of Neurosurgery showed a steady increase in female first and senior authorship, with a plateau beginning in the 1990s. CONCLUSIONS: Large meta-analysis techniques have the potential to effectively leverage large amounts of bibliometric data to quantify the representation of female authorship in the neurosurgical literature. The proportion of female authors in major neurosurgical journals has steadily increased. However, the rate of increase in female senior authorship has lagged behind the rate of increase in first authorship, indicating a disparity in academic advancement in women in neurosurgery.

An integrated disease-specific graded prognostic assessment scale for melanoma: contributions of KPS, CITV, number of metastases, and BRAF mutation status.

BACKGROUND: Stereotactic radiosurgery (SRS) remains a mainstay therapy in the treatment of melanoma brain metastases (BM). While prognostic scales have been developed for melanoma patients who underwent SRS treatment for BM, the pertinence of these scales in the context of molecularly targeted therapies remains unclear. METHODS: Through a multi-institutional collaboration, we collated the survival patterns of 331 melanoma BM patients with known BRAF mutation status treated with SRS. We established a prognostic scale that was validated in an independent cohort of 174 patients. All patients with BRAF mutations in this series were treated with BRAF inhibitors. Prognostic utility was assessed using Net Reclassification Index (NRI > 0) and integrated discrimination improvement (IDI) metrics. RESULTS: In a multivariate Cox proportional hazards model, BRAF mutation status, KPS, number of metastases, and cumulative intracranial tumor volume (CITV) independently contributed to survival prognostication for melanoma patients with SRS-treated BM (P < .05 for all variables). These variables were incorporated into a prognostic scale using the disease-specific graded prognostic assessment (ds-GPA) framework. This integrated melanoma ds-GPA scale was validated in 2 independent cohorts collated through a multi-institutional collaboration. In terms of order of prognostic importance, BRAF mutation status exerted the greatest influence on survival, while KPS, the number of metastases, and CITV exhibited comparable, lesser impacts. CONCLUSIONS: Optimal survival prognostication for SRS-treated patients with melanoma BM requires an integrated assessment of patient characteristics (KPS), tumor characteristics (CITV and number of metastases), and the mutational profile of the melanoma (BRAF mutation status).

Missing diversity in brain tumor trials.

BACKGROUND: Clinical trials for brain tumors represent a significant opportunity for both patients and providers to understand and combat a disease with substantial morbidity. The aim of this study was to quantify and map ethnic and racial representation in brain tumor trials and examine the potential gaps in trial recruitment. We also show that these representation gaps persist even in large multicultural cities like New York City. METHODS: We analyzed brain tumor clinical trials registered on www.clinicaltrials.gov between July 1, 2005 and completed on or before November 11, 2017. We used a combination of PubMed/MEDLINE and Google Scholar to find associated publications and obtained trial information as well as patient demographic information (when available) including race or ancestry. RESULTS: Out of 471 trials, 27% had no published results. Only 28.4% of trials with results reported race or ethnicity of trial participants, with no observed upward trend by year. Whites were significantly overrepresented in trials for metastatic brain tumors (P < .001) and high-grade trials (P < .001). Blacks/African Americans (AAs), Hispanics, and Asians were significantly underrepresented (P < .001) in high-grade trials, while only Blacks/AAs were underrepresented in trials for metastatic brain tumors (P < .001). Representation gaps were not observed in pediatric trials. Despite being a multicultural hub, New York City displayed similar gaps in trial representation. CONCLUSIONS: Despite increasing representation in the American population, minorities are underrepresented in brain tumor trials. In addition, despite numerous legal requirements and ethical mandates, published results including race-based information are remarkably absent from 70% of brain tumor trials.

Glioblastomas located in proximity to the subventricular zone (SVZ) exhibited enrichment of gene expression profiles associated with the cancer stem cell state.

INTRODUCTION: Conflicting results have been reported in the association between glioblastoma proximity to the subventricular zone (SVZ) and enrichment of cancer stem cell properties. Here, we examined this hypothesis using magnetic resonance (MR) images derived from 217 The Cancer Imaging Archive (TCIA) glioblastoma subjects. METHODS: Pre-operative MR images were segmented automatically into contrast enhancing (CE) tumor volumes using Iterative Probabilistic Voxel Labeling (IPVL). Distances were calculated from the centroid of CE tumor volumes to the SVZ and correlated with gene expression profiles of the corresponding glioblastomas. Correlative analyses were performed between SVZ distance, gene expression patterns, and clinical survival. RESULTS: Glioblastoma located in proximity to the SVZ showed increased mRNA expression patterns associated with the cancer stem-cell state, including CD133 (P = 0.006). Consistent with the previous observations suggesting that glioblastoma stem cells exhibit increased DNA repair capacity, glioblastomas in proximity to the SVZ also showed increased expression of DNA repair genes, including MGMT (P = 0.018). Reflecting this enhanced DNA repair capacity, the genomes of glioblastomas in SVZ proximity harbored fewer single nucleotide polymorphisms relative to those located distant to the SVZ (P = 0.003). Concordant with the notion that glioblastoma stem cells are more aggressive and refractory to therapy, patients with glioblastoma in proximity to SVZ exhibited poorer progression free and overall survival (P < 0.01). CONCLUSION: An unbiased analysis of TCIA suggests that glioblastomas located in proximity to the SVZ exhibited mRNA expression profiles associated with stem cell properties, increased DNA repair capacity, and is associated with poor clinical survival.