Thalamic stereoelectroencephalography in epilepsy surgery: a scoping literature review.

OBJECTIVE: Stereoelectroencephalography (sEEG) is a well-established surgical method for defining the epileptogenic network. Traditionally reserved for identifying discrete cortical regions for resection or ablation, sEEG in current practice is also used for identifying more broadly involved subcortical epileptic network components, driven by the availability of brain-based neuromodulation strategies. In particular, sEEG investigations including thalamic nuclei are becoming more frequent in parallel with the increase in therapeutic strategies involving thalamic targets such as deep brain stimulation (DBS) and responsive neurostimulation (RNS). The objective to this study was to evaluate existing evidence and trends regarding the purpose, techniques, and relevant electrographic findings of thalamic sEEG. METHODS: MEDLINE and Embase databases were systematically queried for eligible peer-reviewed studies involving sEEG electrode implantation into thalamic nuclei of patients with epilepsy. Available data were abstracted concerning preoperative workup and purpose for implanting the thalamus, thalamic targets and trajectories, and electrophysiological methodology and findings. RESULTS: sEEG investigations have included thalamic targets for both basic and clinical research purposes. Medial pulvinar, dorsomedial, anterior, and centromedian nuclei have been the most frequently studied. Few studies have reported any complications with thalamic sEEG implantation, and no studies have reported long-term complications. Various methods have been utilized to characterize thalamic activity in epileptic disorders including evoked potentials, power spectrograms, synchronization indices, and the epileptogenicity index. Thalamic intracranial recordings are beginning to be used to guide neuromodulation strategies including RNS and DBS, as well as to understand complex, network-dependent seizure disorders. CONCLUSIONS: Inclusion of thalamic coverage during sEEG evaluation in drug-resistant epilepsy is a growing practice and is amenable to various methods of electrographic data analysis. Further study is required to establish well-defined criteria for thalamic implantation during invasive investigations as well as safety and ethical considerations.

Delayed Diagnosis of Charcot Foot: A Systematic Review.

This study aims to examine the duration and rate of delayed diagnosis in Charcot foot. We systematically reviewed articles published in Medline, SCOPUS, and Cumulative Index of Nursing and Allied Health Literature to identify articles discussing delayed or misdiagnosis of Charcot foot. Random-effects models were generated to determine the average time from symptom onset to correct diagnosis (diagnostic delay duration) and proportion of patients misdiagnosed prior to being correctly diagnosed (delayed diagnosis rate). Our search identified 142 articles, 7 of which are included in this review. The review found that 53.2% of cases of Charcot osteoarthropathy experienced a delay in diagnosis (95% CI: 28.9%-77.4%). Overall, the duration of diagnostic delay was determined to be 86.9 days (95% CI: 10.5-162.1). We found that patients with Charcot foot experienced prolonged delays from symptom onset to correct diagnosis, and a majority of patients are misdiagnosed. These delays in diagnosis contribute to worse patient outcomes.

Predicting in-hospital mortality after traumatic brain injury: External validation of CRASH-basic and IMPACT-core in the national trauma data bank.

BACKGROUND: Traumatic brain injury (TBI) prognostic prediction models offer value to individualized treatment planning, systematic outcome assessments and clinical research design but require continuous external validation to ensure generalizability to different settings. The Corticosteroid Randomization After Significant Head Injury (CRASH) and International Mission on Prognosis and Analysis on Clinical Trials in TBI (IMPACT) models are widely available but lack robust assessments of performance in a current national sample of patients. The purpose of this study is to assess the performance of the CRASH-Basic and IMPACT-Core models in predicting in-hospital mortality using a nationwide retrospective cohort from the National Trauma Data Bank (NTDB). METHODS: The 2016 NTDB was used to analyze an adult cohort with moderate-severe TBI (Glasgow Coma Scale [GCS] ≤ 12, head Abbreviated Injury Scale of 2-6). Observed in-hospital mortality or discharge to hospice was compared to the CRASH-Basic and IMPACT-Core models' predicted probability of 14-day or 6-month mortality, respectively. Performance measures included discrimination (area under the receiver operating characteristic curve [AUC]) and calibration (calibration plots and Brier scores). Further sensitivity analysis included patients with GCS ≤ 14 and considered patients discharged to hospice to be alive at 14-days. RESULTS: A total of 26,228 patients were included in this study. Both models demonstrated good ability in differentiating between patients who died and those who survived, with IMPACT demonstrating a marginally greater AUC (0.863; 95% CI: 0.858 - 0.867) than CRASH (0.858; 0.854 - 0.863); p < 0.001. On calibration, IMPACT overpredicted at lower scores and underpredicted at higher scores but had good calibration-in-the-large (indicating no systemic over/underprediction), while CRASH consistently underpredicted mortality. Brier scores were similar (0.152 for IMPACT, 0.162 for CRASH; p < 0.001). Both models showed slight improvement in performance when including patients with GCS ≤ 14. CONCLUSION: Both CRASH-Basic and IMPACT-Core accurately predict in-hospital mortality following moderate-severe TBI, and IMPACT-Core performs well beyond its original GCS cut-off of 12, indicating potential utility for mild TBI (GCS 13-15). By demonstrating validity in the NTDB, these models appear generalizable to new data and offer value to current practice in diverse settings as well as to large-scale research design.

Geographical Variation in Traumatic Brain Injury Mortality by Proximity to the Nearest Neurosurgeon.

BACKGROUND: Trauma mortality disproportionately affects populations farther from potentially lifesaving trauma care, and traumatic brain injury (TBI) is no exception. Previous examinations have examined proximity to trauma centers as an explanation for trauma mortality, but little is known about the relationship between proximity to neurosurgeons specifically in TBI mortality. MATERIALS AND METHODS: In this cross-sectional study, county-level TBI mortality rates from 2008 to 2014 were examined in relation to the distance to the nearest neurosurgeon and trauma facility. The locations of practicing neurosurgeons and trauma facilities in the United States were determined by geocoding data from the 2017 Medicare Physician and Other Supplier and Provider of Services files (respectively). The association between TBI mortality and the distance from the population-weighted centroid of the county to a closest neurosurgeon and trauma facility was examined using multivariate negative binomial regression. RESULTS: A total of 761 of the 3108 counties (24.5%) in the continental United States were excluded from the analysis because they had 20 or fewer TBI deaths during this time, producing unstable estimates. Excluded counties accounted for 1.67% of the US population. Multivariate analysis revealed a county's mortality increased 10% for every 25 miles from the nearest neurosurgeon (adjusted incident rate ratio: 1.10 [95% confidence interval: 1.08-1.12]; P < 0.001). The distance to the nearest trauma facility was not found to be significantly associated with mortality (adjusted incident rate ratio: 1.01 [95% confidence interval: 0.99-1.03]; P = 0.36). CONCLUSIONS: These findings suggest that proximity to neurosurgeons may influence county-level TBI mortality. Further research into this topic with more granular data may help to allocate scarce public health resources.

A Systematic Review of Ion Radiotherapy in Maintaining Local Control Regarding Atypical and Anaplastic Meningiomas.

OBJECTIVE: Atypical and anaplastic meningiomas, unlike their benign counterparts, are highly aggressive, locally destructive, and likely to recur after treatment. These diseases are difficult to definitively treat with traditional radiotherapy without injuring adjacent brain parenchyma. The physical properties of ion radiotherapy allows for treatment plans that avoid damaging critical neural structures. The objectives of this systematic review were to evaluate the use and efficacy of ion radiotherapy in the treatment of atypical and anaplastic meningiomas. METHODS: We performed a systematic review of the literature by querying the PubMed and Ovid databases to identify and examine literature addressing the efficacy of ion radiotherapy in maintaining long-term local tumor control for patients with atypical or anaplastic meningiomas. The outcome of interest was rate of local tumor control at 5 years after ion radiotherapy. RESULTS: Across the included studies, proton therapy delivered a mean local control rate of 59.62% after 5 years. Carbon ion radiotherapy studies showed local control rates of 95% and 63% at 2 years for grade II and III meningiomas, respectively. In contrast, carbon ion radiotherapy studies that failed to differentiate between atypical and anaplastic meningiomas produced a local control rate of 33% at 2 years. CONCLUSIONS: Proton and carbon ion radiotherapy maintain comparable rates of local control to conventional photon therapy and allow for more targeted treatment plans that may limit excess radiation damage. Although additional prospective trials are needed, ion therapy represents a burgeoning field in the treatment of atypical and anaplastic meningiomas.