Performance of the IMPACT and CRASH prognostic models for traumatic brain injury in a contemporary multicenter cohort: a TRACK-TBI study

OBJECTIVE

The International Mission on Prognosis and Analysis of Clinical Trials in Traumatic Brain Injury (IMPACT) and Corticosteroid Randomization After Significant Head Injury (CRASH) prognostic models for mortality and outcome after traumatic brain injury (TBI) were developed using data from 1984 to 2004. This study examined IMPACT and CRASH model performances in a contemporary cohort of US patients.

METHODS

The prospective 18-center Transforming Research and Clinical Knowledge in Traumatic Brain Injury (TRACK-TBI) study (enrollment years 2014-2018) enrolled subjects aged ≥ 17 years who presented to level I trauma centers and received head CT within 24 hours of TBI. Data were extracted from the subjects who met the model criteria (for IMPACT, Glasgow Coma Scale [GCS] score 3-12 with 6-month Glasgow Outcome Scale-Extended [GOSE] data [n = 441]; for CRASH, GCS score 3-14 with 2-week mortality data and 6-month GOSE data [n = 831]). Analyses were conducted in the overall cohort and stratified on the basis of TBI severity (severe/moderate/mild TBI defined as GCS score 3-8/9-12/13-14), age (17-64 years or ≥ 65 years), and the 5 top enrolling sites. Unfavorable outcome was defined as GOSE score 1-4. Original IMPACT and CRASH model coefficients were applied, and model performances were assessed by calibration (intercept [< 0 indicated overprediction; > 0 indicated underprediction] and slope) and discrimination (c-statistic).

RESULTS

Overall, the IMPACT models overpredicted mortality (intercept -0.79 [95% CI -1.05 to -0.53], slope 1.37 [1.05-1.69]) and acceptably predicted unfavorable outcome (intercept 0.07 [-0.14 to 0.29], slope 1.19 [0.96-1.42]), with good discrimination (c-statistics 0.84 and 0.83, respectively). The CRASH models overpredicted mortality (intercept -1.06 [-1.36 to -0.75], slope 0.96 [0.79-1.14]) and unfavorable outcome (intercept -0.60 [-0.78 to -0.41], slope 1.20 [1.03-1.37]), with good discrimination (c-statistics 0.92 and 0.88, respectively). IMPACT overpredicted mortality and acceptably predicted unfavorable outcome in the severe and moderate TBI subgroups, with good discrimination (c-statistic ≥ 0.81). CRASH overpredicted mortality in the severe and moderate TBI subgroups and acceptably predicted mortality in the mild TBI subgroup, with good discrimination (c-statistic ≥ 0.86); unfavorable outcome was overpredicted in the severe and mild TBI subgroups with adequate discrimination (c-statistic ≥ 0.78), whereas calibration was nonlinear in the moderate TBI subgroup. In subjects ≥ 65 years of age, the models performed variably (IMPACT-mortality, intercept 0.28, slope 0.68, and c-statistic 0.68; CRASH-unfavorable outcome, intercept -0.97, slope 1.32, and c-statistic 0.88; nonlinear calibration for IMPACT-unfavorable outcome and CRASH-mortality). Model performance differences were observed across the top enrolling sites for mortality and unfavorable outcome.

CONCLUSIONS

The IMPACT and CRASH models adequately discriminated mortality and unfavorable outcome. Observed overestimations of mortality and unfavorable outcome underscore the need to update prognostic models to incorporate contemporary changes in TBI management and case-mix. Investigations to elucidate the relationships between increased survival, outcome, treatment intensity, and site-specific practices will be relevant to improve models in specific TBI subpopulations (e.g., older adults), which may benefit from the inclusion of blood-based biomarkers, neuroimaging features, and treatment data.

Isolated Traumatic Subarachnoid Hemorrhage on Head Computed Tomography Scan May Not Be Isolated: A TRACK-TBI Study

Isolated traumatic subarachnoid hemorrhage (tSAH) after traumatic brain injury (TBI) on head computed tomography (CT) scan is often regarded as a "mild" injury, with reduced need for additional workup. However, tSAH is also a predictor of incomplete recovery and unfavorable outcome. This study aimed to evaluate the characteristics of CT-occult intracranial injuries on brain magnetic resonance imaging (MRI) scan in TBI patients with emergency department (ED) arrival Glasgow Coma Scale (GCS) score 13-15 and isolated tSAH on CT. The prospective, 18-center Transforming Research and Clinical Knowledge in Traumatic Brain Injury Study (TRACK-TBI; enrollment years 2014-2019) enrolled participants who presented to the ED and received a clinically-indicated head CT within 24 hours (h) of TBI. A subset of TRACK-TBI participants underwent venipuncture within 24h for plasma glial fibrillary acidic protein (GFAP) analysis, and research MRI at 2-weeks post-injury. In the current study, TRACK-TBI participants aged ≥17 years with ED arrival GCS 13-15, isolated tSAH on initial head CT, plasma GFAP level, and 2-week MRI data were analyzed. In 57 participants, median age was 46.0 years [quartile 1 to 3 (Q1-Q3): 34-57] and 52.6% were male. At ED disposition, 12.3% were discharged home, 61.4% were admitted to hospital ward, and 26.3% to intensive care unit. MRI identified CT-occult traumatic intracranial lesions in 45.6% (26 of 57 participants; 1 additional lesion type: 31.6%; 2 additional lesion types: 14.0%); of these 26 participants with CT-occult intracranial lesions, 65.4% had axonal injury, 42.3% had subdural hematoma, and 23.1% had intracerebral contusion. GFAP levels were higher in participants with CT-occult MRI lesions compared to without (median: 630.6 pg/ml, Q1-Q3: [172.4-941.2] vs. 226.4 [105.8-436.1], p=0.049), and were associated with axonal injury (no: median 226.7 pg/ml [109.6-435.1], yes: 828.6 pg/ml [204.0-1194.3], p=0.009). Our results indicate that isolated tSAH on head CT is often not the sole intracranial traumatic injury in GCS 13-15 TBI. Forty-six percent of patients in our cohort (26 of 57 participants) had additional CT-occult traumatic lesions on MRI. Plasma GFAP may be an important biomarker for the identification of additional CT-occult injuries, including axonal injury. These findings should be interpreted cautiously given our modest sample size and await validation from larger studies.

Medicaid Insurance is a Predictor of Prolonged Hospital Length of Stay After Traumatic Brain Injury: A Stratified National Trauma Data Bank Cohort Analysis of 552 949 Patients

BACKGROUND AND OBJECTIVES

Hospital length of stay (HLOS) is a metric of injury severity, resource utilization, and healthcare access. Recent evidence has shown an association between Medicaid insurance and increased HLOS after traumatic brain injury (TBI). This study aims to validate the association between Medicaid and prolonged HLOS after TBI using the National Trauma Data Bank.

METHODS

National Trauma Data Bank Trauma Quality Programs Participant Use Files (2003-2021) were queried for adult patients with TBI using traumatic intracranial injury ICD-9/ICD-10 codes. Patients with complete HLOS, age, sex, race, insurance payor, Glasgow Coma Scale, Injury Severity Score, and discharge disposition data were included (N = 552 949). Analyses were stratified by TBI severity using Glasgow Coma Scale. HLOS was coded into Tiers according to percentiles within TBI severity categories (Tier 1: 1-74th; 2: 75-84th; 3: 85-94th; 4: 95-99th). Multivariable logistic regressions evaluated associations between insurance payor and prolonged (Tier 4) HLOS, controlling for sociodemographic, Injury Severity Score, cranial surgery, and discharge disposition variables. Adjusted odds ratios (aOR) and 95% CI were reported.

RESULTS

HLOS Tiers consisted of 0-19, 20-27, 28-46, and ≥47 days (Tiers 1-4, respectively) in severe TBI (N = 103 081); 0-15, 16-21, 22-37, and ≥38 days in moderate TBI (N = 39 904); and 0-7, 8-10, 11-19, and ≥20 days in mild TBI (N = 409 964). Proportion of Medicaid patients increased with Tier ([Tier 1 vs Tier 4] severe: 16.0% vs 36.1%; moderate: 14.1% vs 31.6%; mild TBI: 10.2% vs 17.4%; all P < .001). On multivariable analyses, Medicaid was associated with prolonged HLOS (severe TBI: aOR = 2.35 [2.19-2.52]; moderate TBI: aOR = 2.30 [2.04-2.61]; mild TBI: aOR = 1.75 [1.67-1.83]; reference category: private/commercial).

CONCLUSION

This study supports Medicaid as an independent predictor of prolonged HLOS across TBI severity strata. Reasons may include different efficacies in care delivery and reimbursement, which require further investigation. Our findings support the development of discharge coordination pathways and policies for Medicaid patients with TBI.

Longitudinal Recovery Following Repetitive Traumatic Brain Injury

Importance

One traumatic brain injury (TBI) increases the risk of subsequent TBIs. Research on longitudinal outcomes of civilian repetitive TBIs is limited.

Objective

To investigate associations between sustaining 1 or more TBIs (ie, postindex TBIs) after study enrollment (ie, index TBIs) and multidimensional outcomes at 1 year and 3 to 7 years.

Design, Setting, and Participants

This cohort study included participants presenting to emergency departments enrolled within 24 hours of TBI in the prospective, 18-center Transforming Research and Clinical Knowledge in Traumatic Brain Injury (TRACK-TBI) study (enrollment years, February 2014 to July 2020). Participants who completed outcome assessments at 1 year and 3 to 7 years were included. Data were analyzed from September 2022 to August 2023.

Exposures

Postindex TBI(s).

Main Outcomes and Measures

Demographic and clinical factors, prior TBI (ie, preindex TBI), and functional (Glasgow Outcome Scale-Extended [GOSE]), postconcussive (Rivermead Post-Concussion Symptoms Questionnaire [RPQ]), psychological distress (Brief Symptom Inventory-18 [BSI-18]), depressive (Patient Health Questionnaire-9 [PHQ-9]), posttraumatic stress disorder (PTSD; PTSD Checklist for DSM-5 [PCL-5]), and health-related quality-of-life (Quality of Life After Brain Injury-Overall Scale [QOLIBRI-OS]) outcomes were assessed. Adjusted mean differences (aMDs) and adjusted relative risks are reported with 95% CIs.

Results

Of 2417 TRACK-TBI participants, 1572 completed the outcomes assessment at 1 year (1049 [66.7%] male; mean [SD] age, 41.6 [17.5] years) and 1084 completed the outcomes assessment at 3 to 7 years (714 [65.9%] male; mean [SD] age, 40.6 [17.0] years). At 1 year, a total of 60 participants (4%) were Asian, 255 (16%) were Black, 1213 (77%) were White, 39 (2%) were another race, and 5 (0.3%) had unknown race. At 3 to 7 years, 39 (4%) were Asian, 149 (14%) were Black, 868 (80%) were White, 26 (2%) had another race, and 2 (0.2%) had unknown race. A total of 50 (3.2%) and 132 (12.2%) reported 1 or more postindex TBIs at 1 year and 3 to 7 years, respectively. Risk factors for postindex TBI were psychiatric history, preindex TBI, and extracranial injury severity. At 1 year, compared with those without postindex TBI, participants with postindex TBI had worse functional recovery (GOSE score of 8: adjusted relative risk, 0.57; 95% CI, 0.34-0.96) and health-related quality of life (QOLIBRI-OS: aMD, -15.9; 95% CI, -22.6 to -9.1), and greater postconcussive symptoms (RPQ: aMD, 8.1; 95% CI, 4.2-11.9), psychological distress symptoms (BSI-18: aMD, 5.3; 95% CI, 2.1-8.6), depression symptoms (PHQ-9: aMD, 3.0; 95% CI, 1.5-4.4), and PTSD symptoms (PCL-5: aMD, 7.8; 95% CI, 3.2-12.4). At 3 to 7 years, these associations remained statistically significant. Multiple (2 or more) postindex TBIs were associated with poorer outcomes across all domains.

Conclusions and Relevance

In this cohort study of patients with acute TBI, postindex TBI was associated with worse symptomatology across outcome domains at 1 year and 3 to 7 years postinjury, and there was a dose-dependent response with multiple postindex TBIs. These results underscore the critical need to provide TBI prevention, education, counseling, and follow-up care to at-risk patients.

Socioeconomic and clinical factors associated with prolonged hospital length of stay after traumatic brain injury

BACKGROUND

Hospital length of stay (HLOS) after traumatic brain injury (TBI) is a metric of injury severity, resource utilization, and access to services. This study aimed to evaluate socioeconomic and clinical factors associated with prolonged HLOS after TBI.

METHODS

Retrospective data from adult hospitalized patients diagnosed with acute TBI at a US Level 1 trauma center between August 1, 2019 - April 1, 2022 were extracted from the electronic health record. HLOS was stratified by Tier (1: 1-74th percentile; 2: 75-84th; 3: 85-94th; 4: 95-99th). Demographic, socioeconomic, injury severity, and level-of-care factors were compared by HLOS. Multivariable logistic regressions evaluated associations between socioeconomic and clinical variables and prolonged HLOS, using multivariable odds ratios (mOR) and [95% confidence intervals]. Estimated daily charges were calculated for a subset of medically-stable inpatients awaiting placement. Statistical significance was assessed at p < 0.05.

RESULTS

In 1443 patients, median HLOS was 4 days (interquartile range 2-8; range 0-145). HLOS Tiers were 0-7, 8-13, 14-27, and ≥28 days (Tiers 1-4, respectively). Patients with Tier 4 HLOS differed significantly from others, with increased Medicaid insurance (53.4% vs. 30.3-33.1%, p = 0.003), severe TBI (Glasgow Coma Scale 3-8: 38.4% vs. 8.7-18.2%, p < 0.001), younger age (mean 52.3-years vs. 61.1-63.7-years, p = 0.003), low socioeconomic status (53.4% vs. 32.0-33.9%, p = 0.003), and need for post-acute care (60.3% vs. 11.2-39.7%, p < 0.001). Independent factors associated with prolonged (Tier 4) HLOS were Medicaid (mOR = 1.99 [1.08-3.68], vs. Medicare/commercial), moderate and severe TBI (mOR = 3.48 [1.61-7.56]; mOR = 4.43 [2.18-8.99], respectively, vs. mild TBI), and need for post-acute placement (mOR = 10.68 [5.74-19.89], while age was protective (per-year mOR = 0.98 [0.97-0.99]). Estimated daily charges for a medically-stable inpatient was $17126.

CONCLUSIONS

Medicaid insurance, moderate/severe TBI, and need for post-acute care were independently associated with prolonged HLOS ≥28 days. Medically-stable inpatients awaiting placement accrue immense daily healthcare costs. At-risk patients should be identified early, receive care transitions resources, and be prioritized for discharge coordination pathways.

A standardized postoperative bowel regimen protocol after spine surgery

Objectives

Spine surgery is associated with early impairment of gastrointestinal motility, with postoperative ileus rates of 5–12%. A standardized postoperative medication regimen aimed at early restoration of bowel function can reduce morbidity and cost, and its study should be prioritized.

Methods

A standardized postoperative bowel medication protocol was implemented for all elective spine surgeries performed by a single neurosurgeon from March 1, 2022 to June 30, 2022 at a metropolitan Veterans Affairs medical center. Daily bowel function was tracked and medications were advanced using the protocol. Clinical, surgical, and length of stay data are reported.

Results

Across 20 consecutive surgeries in 19 patients, mean age was 68.9 years [standard deviation (SD) = 10; range 40–84]. Seventy-four percent reported preoperative constipation. Surgeries consisted of 45% fusion and 55% decompression; lumbar retroperitoneal approaches constituted 30% (10% anterior, 20% lateral). Two patients were discharged in good condition prior to bowel movement after meeting institutional discharge criteria; the other 18 cases all had return of bowel function by postoperative day (POD) 3 (mean = 1.8-days, SD = 0.7). There were no inpatient or 30-day complications. Mean discharge occurred 3.3-days post-surgery (SD = 1.5; range 1–6; home 95%, skilled nursing facility 5%). Estimated cumulative cost of the bowel regimen was $17 on POD 3.

Conclusions

Careful monitoring of return of bowel function after elective spine surgery is important for preventing ileus, reducing healthcare cost, and ensuring quality. Our standardized postoperative bowel regimen was associated with return of bowel function within 3 days and low costs. These findings can be utilized in quality-of-care pathways.

Neuroworsening in the Emergency Department Is a Predictor of Traumatic Brain Injury Intervention and Outcome: A TRACK-TBI Pilot Study

INTRODUCTION

Neuroworsening may be a sign of progressive brain injury and is a factor for treatment of traumatic brain injury (TBI) in intensive care settings. The implications of neuroworsening for clinical management and long-term sequelae of TBI in the emergency department (ED) require characterization.

METHODS

Adult TBI subjects from the prospective Transforming Research and Clinical Knowledge in Traumatic Brain Injury Pilot Study with ED admission and disposition Glasgow Coma Scale (GCS) scores were extracted. All patients received head computed tomography (CT) scan <24 h post-injury. Neuroworsening was defined as a decline in motor GCS at ED disposition (vs. ED admission). Clinical and CT characteristics, neurosurgical intervention, in-hospital mortality, and 3- and 6-month Glasgow Outcome Scale-Extended (GOS-E) scores were compared by neuroworsening status. Multivariable regressions were performed for neurosurgical intervention and unfavorable outcome (GOS-E ≤ 3). Multivariable odds ratios (mOR) with [95% confidence intervals] were reported.

RESULTS

In 481 subjects, 91.1% had ED admission GCS 13-15 and 3.3% had neuroworsening. All neuroworsening subjects were admitted to intensive care unit (vs. non-neuroworsening: 26.2%) and were CT-positive for structural injury (vs. 45.4%). Neuroworsening was associated with subdural (75.0%/22.2%), subarachnoid (81.3%/31.2%), and intraventricular hemorrhage (18.8%/2.2%), contusion (68.8%/20.4%), midline shift (50.0%/2.6%), cisternal compression (56.3%/5.6%), and cerebral edema (68.8%/12.3%; all p < 0.001). Neuroworsening subjects had higher likelihoods of cranial surgery (56.3%/3.5%), intracranial pressure (ICP) monitoring (62.5%/2.6%), in-hospital mortality (37.5%/0.6%), and unfavorable 3- and 6-month outcome (58.3%/4.9%; 53.8%/6.2%; all p < 0.001). On multivariable analysis, neuroworsening predicted surgery (mOR = 4.65 [1.02-21.19]), ICP monitoring (mOR = 15.48 [2.92-81.85], and unfavorable 3- and 6-month outcome (mOR = 5.36 [1.13-25.36]; mOR = 5.68 [1.18-27.35]).

CONCLUSIONS

Neuroworsening in the ED is an early indicator of TBI severity, and a predictor of neurosurgical intervention and unfavorable outcome. Clinicians must be vigilant in detecting neuroworsening, as affected patients are at increased risk for poor outcomes and may benefit from immediate therapeutic interventions.

Predictors of Extreme Hospital Length of Stay After Traumatic Brain Injury

BACKGROUND

Hospital length of stay (HLOS) after traumatic brain injury (TBI) is an important metric of injury severity, resource utilization, and access to post-acute care services. Risk factors for protracted HLOS after TBI require further characterization.

METHODS

Data regarding adult inpatients admitted to a single U.S. level 1 trauma center with a diagnosis of acute TBI between August 1, 2019, and April 1, 2022, were extracted from the electronic health record. Patients with extreme HLOS (XHLOS, >99th percentile of institutional TBI HLOS) were compared with those without XHLOS. Socioeconomic status (SES), clinical/injury factors, and discharge disposition were analyzed.

RESULTS

In 1638 patients, the median HLOS was 3 days (interquartile range [IQR]: 2-8 days). XHLOS threshold was >70 days (N = 18; range: 72-146 days). XHLOS was associated with younger age (XHLOS/non-XHLOS: 50.4/59.6 years; P = 0.042) and greater proportions with severe TBI (55.6%/11.4%; P < 0.001), low SES (72.2%/31.4%; P < 0.001), and Medicaid insurance (77.8%/30.1%; P < 0.001). XHLOS patients were more likely to die in hospital (22.2%/8.1%) and discharge to post-acute facility (77.8%/16.3%; P < 0.001). No XHLOS patients were discharged to home. In XHLOS patients alive at discharge, medical stability was documented at median 39 days (IQR: 28-58 days) and were hospitalized for another 56 days (IQR: 26.5-78.5 days).

CONCLUSIONS

XHLOS patients were more likely to have severe injuries, low SES, and Medicaid. XHLOS is associated with in-hospital mortality and need for post-acute placement. XHLOS patients often demonstrated medical stability long before placement, underscoring complex relationships between SES, health insurance, and outcome. These findings have important implications for quality improvement and resource utilization at acute care hospitals and await validation from larger trials.

Evacuation of a multi-loculated acute-on-chronic subdural hematoma using tandem bedside subdural evacuation port systems

Background

Purpose

Findings

Conclusions

Is the Centers for Medicare and Medicaid Services Hierarchical Condition Category Risk Adjustment Model Satisfactory for Quantifying Risk After Spine Surgery?

BACKGROUND

The Centers for Medicare and Medicaid Services (CMS) hierarchical condition category (HCC) coding is a risk adjustment model that allows for the estimation of risk-and cost-associated with health care provision. Current models may not include key factors that fully delineate the risk associated with spine surgery.

OBJECTIVE

To augment CMS HCC risk adjustment methodology with socioeconomic data to improve its predictive capabilities for spine surgery.

METHODS

The National Inpatient Sample was queried for spinal fusion, and the data was merged with county-level coverage and socioeconomic status variables obtained from the Brookings Institute. We predicted outcomes (death, nonroutine discharge, length of stay [LOS], total charges, and perioperative complication) with pairs of hierarchical, mixed effects logistic regression models-one using CMS HCC score alone and another augmenting CMS HCC scores with demographic and socioeconomic status variables. Models were compared using receiver operating characteristic curves. Variable importance was assessed in conjunction with Wald testing for model optimization.

RESULTS

We analyzed 653 815 patients. Expanded models outperformed models using CMS HCC score alone for mortality, nonroutine discharge, LOS, total charges, and complications. For expanded models, variable importance analyses demonstrated that CMS HCC score was of chief importance for models of mortality, LOS, total charges, and complications. For the model of nonroutine discharge, age was the most important variable. For the model of total charges, unemployment rate was nearly as important as CMS HCC score.

CONCLUSION

The addition of key demographic and socioeconomic characteristics substantially improves the CMS HCC risk-adjustment models when modeling spinal fusion outcomes. This finding may have important implications for payers, hospitals, and policymakers.

Do social determinants of health impact access to neurosurgical care in the United States? A workforce perspective

OBJECTIVE

This study attempts to use neurosurgical workforce distribution to uncover the social determinants of health that are associated with disparate access to neurosurgical care.

METHODS

Data were compiled from public sources and aggregated at the county level. Socioeconomic data were provided by the Brookings Institute. Racial and ethnicity data were gathered from the Centers for Disease Control and Prevention Wide-ranging Online Data for Epidemiologic Research. Physician density was retrieved from the Health Resources and Services Administration Area Health Resources Files. Catchment areas were constructed based on the 628 counties with neurosurgical coverage, with counties lacking neurosurgical coverage being integrated with the nearest covered county based on distances from the National Bureau of Economic Research's County Distance Database. Catchment areas form a mutually exclusive and collectively exhaustive breakdown of the entire US population and licensed neurosurgeons. Socioeconomic factors, race, and ethnicity were chosen as independent variables for analysis. Characteristics for each catchment area were calculated as the population-weighted average across all contained counties. Linear regression analysis modeled two outcomes of interest: neurosurgeon density per capita and average distance to neurosurgical care. Coefficient estimates (CEs) and 95% confidence intervals were calculated and scaled by 1 SD to allow for comparison between variables.

RESULTS

Catchment areas with higher poverty (CE = 0.64, 95% CI 0.34-0.93) and higher prime age employment (CE = 0.58, 95% CI 0.40-0.76) were significantly associated with greater neurosurgeon density. Among categories of race and ethnicity, catchment areas with higher proportions of Black residents (CE = 0.21, 95% CI 0.06-0.35) were associated with greater neurosurgeon density. Meanwhile, catchment areas with higher proportions of Hispanic residents displayed lower neurosurgeon density (CE = -0.17, 95% CI -0.30 to -0.03). Residents of catchment areas with higher housing vacancy rates (CE = 2.37, 95% CI 1.31-3.43), higher proportions of Native American residents (CE = 4.97, 95% CI 3.99-5.95), and higher proportions of Hispanic residents (CE = 2.31, 95% CI 1.26-3.37) must travel farther, on average, to receive neurosurgical care, whereas people living in areas with a lower income (CE = -2.28, 95% CI -4.48 to -0.09) or higher proportion of Black residents (CE = -3.81, 95% CI -4.93 to -2.68) travel a shorter distance.

CONCLUSIONS

Multiple factors demonstrate a significant correlation with neurosurgical workforce distribution in the US, most notably with Hispanic and Native American populations being associated with greater distances to care. Additionally, higher proportions of Hispanic residents correlated with fewer neurosurgeons per capita. These findings highlight the interwoven associations among socioeconomics, race, ethnicity, and access to neurosurgical care nationwide.

Repetitive transcranial magnetic stimulation (rTMS) as therapy in an infant with epilepsia partialis continua

•

rTMS was safely performed in a 10-month old at 10 Hz without apparent adverse effects.

•

rTMS was successfully performed in an infant for refractory epilepsia partialis continua.

•

rTMS may have a treatment role in recurring, refractory epilepsia partialis continua in children.

Introduction: We present a case of a 10-month-old girl undergoing repetitive TMS (rTMS) for the treatment of drug-resistant epilepsy. Case report: A 10-month-old girl, later diagnosed with pathogenic POLG1 mutations, presented to our institution with chronic progressive EPC (epilepsia partialis continua) manifesting as a frequent, left-sided, synchronous continuous jerking of the arms and legs. The seizures were drug-resistant to multiple antiseizure medications and epilepsy surgery, responding only to continuous anesthesia. rTMS therapy was attempted to interrupt seizures. Results: rTMS therapy, using an activating protocol to introduce a temporary lesion effect, was used to interrupt persistent, ongoing seizures. Conclusion: rTMS can be safely used to abort seizures in patients as young as 10 months old.

The Morbidity and Mortality of Surgery for Traumatic Brain Injury in Geriatric Patients: A Study of Over 100 000 Patient Cases

BACKGROUND

Geriatric patients have the highest rates of Traumatic Brain Injury (TBI)-related hospitalization and death. This contributes to an assumption of futility in aggressive management in this population.

OBJECTIVE

To evaluate the effect of surgical intervention on the morbidity and mortality of geriatric patients with TBI.

METHODS

A retrospective analysis of patients ≥80 yr old with TBI from 2003 to 2016 was performed using the National Trauma Data Bank. Univariate and multivariate analyses were performed to compare outcomes between surgery and nonsurgery groups.

RESULTS

A total of 127 129 patient incidents were included: 121 185 (95.3%) without surgery and 5944 (4.7%) with surgery. The surgical group was slightly younger (84.0 vs 84.3, P < .001) and predominantly male (60.2% vs 44.4%, P < .001). Mean emergency department (ED) Glasgow Coma Scale (GCS) was lower in surgical patients (12.4 vs 13.7, P < .001). Complications (OR = 1.91, CI:1.80-2.02, P < .001) and hospital length of stay (LOS, ß = 5.25, CI:5.08-5.42, P < .001) were independently associated with surgery. Intensive care unit (ICU) LOS (ß = 3.19, CI:3.05-3.34, P < .001), ventilator days (ß = 1.57, CI:1.22-1.92, P < .001), and reduced discharge home (OR = 0.434, CI:0.400-0.470, P < .001) were also independently associated with surgery. However, surgery was not independently associated with mortality on multivariate analysis (OR = 1.03, CI:0.955-1.12, P = .423). Recursive partitioning analysis identified ED GCS and injury severity score (ISS) as prognosticators of mortality following surgical intervention.

CONCLUSION

Surgical treatment of geriatric patients with TBI is associated with increased complications, hospital LOS, ICU LOS, and ventilator days as well as reduced discharge to home. However, surgery is not associated with increased mortality. ISS and ED GCS are prognosticators of mortality following surgical intervention.

Does state malpractice environment affect outcomes following spinal fusions? A robust statistical and machine learning analysis of 549,775 discharges following spinal fusion surgery in the United States

OBJECTIVE

Spine surgery is especially susceptible to malpractice claims. Critics of the US medical liability system argue that it drives up costs, whereas proponents argue it deters negligence. Here, the authors study the relationship between malpractice claim density and outcomes.

METHODS

The following methods were used: 1) the National Practitioner Data Bank was used to determine the number of malpractice claims per 100 physicians, by state, between 2005 and 2010; 2) the Nationwide Inpatient Sample was queried for spinal fusion patients; and 3) the Area Resource File was queried to determine the density of physicians, by state. States were categorized into 4 quartiles regarding the frequency of malpractice claims per 100 physicians. To evaluate the association between malpractice claims and death, discharge disposition, length of stay (LOS), and total costs, an inverse-probability-weighted regression-adjustment estimator was used. The authors controlled for patient and hospital characteristics. Covariates were used to train machine learning models to predict death, discharge disposition not to home, LOS, and total costs.

RESULTS

Overall, 549,775 discharges following spinal fusions were identified, with 495,640 yielding state-level information about medical malpractice claim frequency per 100 physicians. Of these, 124,425 (25.1%), 132,613 (26.8%), 130,929 (26.4%), and 107,673 (21.7%) were from the lowest, second-lowest, second-highest, and highest quartile states, respectively, for malpractice claims per 100 physicians. Compared to the states with the fewest claims (lowest quartile), surgeries in states with the most claims (highest quartile) showed a statistically significantly higher odds of a nonhome discharge (OR 1.169, 95% CI 1.139-1.200), longer LOS (mean difference 0.304, 95% CI 0.256-0.352), and higher total charges (mean difference [log scale] 0.288, 95% CI 0.281-0.295) with no significant associations for mortality. For the machine learning models-which included medical malpractice claim density as a covariate-the areas under the curve for death and discharge disposition were 0.94 and 0.87, and the R2 values for LOS and total charge were 0.55 and 0.60, respectively.

CONCLUSIONS

Spinal fusion procedures from states with a higher frequency of malpractice claims were associated with an increased odds of nonhome discharge, longer LOS, and higher total charges. This suggests that medicolegal climate may potentially alter practice patterns for a given spine surgeon and may have important implications for medical liability reform. Machine learning models that included medical malpractice claim density as a feature were satisfactory in prediction and may be helpful for patients, surgeons, hospitals, and payers.

Arteriovenous malformations in the optic apparatus: systematic literature review and report of four cases

OBJECTIVE

Rare arteriovenous malformations (AVMs) of the optic apparatus account for < 1% of all AVMs. The authors conducted a systematic review of the literature for cases of optic apparatus AVMs and present 4 cases from their institution. The literature is summarized to describe preoperative characteristics, surgical technique, and treatment outcomes for these lesions.

METHODS

A comprehensive search of the English-language literature was performed in accordance with established Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to identify all published cases of AVM in the optic apparatus in the PubMed, Web of Science, and Cochrane databases. The authors also searched their prospective institutional database of vascular malformations for such cases. Data regarding the clinical and radiological presentation, visual acuity, visual fields, extent of resection, and postoperative outcomes were gathered.

RESULTS

Nine patients in the literature and 4 patients in the authors' single-surgeon series who fit the inclusion criteria were identified. The median age at presentation was 29 years (range 8-39 years). Among these patients, 11 presented with visual disturbance, 9 with headache, and 1 with multiple prior subarachnoid hemorrhages; the AVM in 1 case was found incidentally. Four patients described prior symptoms of headache or visual disturbance consistent with sentinel events. Visual acuity was decreased from baseline in 10 patients, and 11 patients had visual field defects on formal visual field testing. The most common visual field defect was temporal hemianopia, found in one or both eyes in 7 patients. The optic chiasm was affected in 10 patients, the hypothalamus in 2 patients, the optic nerve (unilaterally) in 8 patients, and the optic tract in 2 patients. Six patients underwent gross-total resection; 6 patients underwent subtotal resection; and 1 patient underwent craniotomy, but no resection was attempted. Postoperatively, 9 of the patients had improved visual function, 1 had no change, and 3 had worse visual acuity. Eight patients demonstrated improved visual fields, 1 had no change, and 4 had narrowed fields.

CONCLUSIONS

AVMs of the optic apparatus are rare lesions. Although they reside in a highly eloquent region, surgical outcomes are generally good; the majority of patients will see improvement in their visual function postoperatively. Microsurgical technique is critical to the successful removal of these lesions, and preservation of function sometimes requires subtotal resection of the lesion.

Navigated transcranial magnetic stimulation mapping of the motor cortex for preoperative diagnostics in pediatric epilepsy

OBJECTIVE

Navigated transcranial magnetic stimulation (nTMS) is a noninvasive technique often used for localization of the functional motor cortex via induction of motor evoked potentials (MEPs) in neurosurgical patients. There has, however, been no published record of its application in pediatric epilepsy surgery. In this study, the authors aimed to investigate the feasibility of nTMS-based motor mapping in the preoperative diagnostic workup within a population of children with medically refractory epilepsy.

METHODS

A single-institution database was screened for preoperative nTMS motor mappings obtained in pediatric patients (aged 0 to 18 years, 2012 to present) with medically refractory epilepsy. Patient clinical data, demographic information, and mapping results were extracted and used in statistical analyses.

RESULTS

Sixteen patients met the inclusion criteria, 15 of whom underwent resection. The median age was 9 years (range 0-17 years). No adverse effects were recorded during mapping. Specifically, no epileptic seizures were provoked via nTMS. Recordings of valid MEPs induced by nTMS were obtained in 10 patients. In the remaining patients, no MEPs could be elicited. Failure to generate MEPs was associated significantly with younger patient age (r = 0.8020, p = 0.0001863). The most frequent seizure control outcome was Engel Epilepsy Surgery Outcome Scale class I (9 patients).

CONCLUSIONS

Navigated TMS is a feasible, effective, and well-tolerated method for mapping the motor cortex of the upper and lower extremities in pediatric patients with epilepsy. Patient age modulates elicitability of MEPs, potentially reflecting various stages of myelination. Successful motor mapping has the potential to add to the existing presurgical diagnostic workup in this population, and further research is warranted.

Preoperative Applications of Navigated Transcranial Magnetic Stimulation

Preoperative mapping of cortical structures prior to neurosurgical intervention can provide a roadmap of the brain with which neurosurgeons can navigate critical cortical structures. In patients undergoing surgery for brain tumors, preoperative mapping allows for improved operative planning, patient risk stratification, and personalized preoperative patient counseling. Navigated transcranial magnetic stimulation (nTMS) is one modality that allows for highly accurate, image-guided, non-invasive stimulation of the brain, thus allowing for differentiation between eloquent and non-eloquent cortical regions. Motor mapping is the best validated application of nTMS, yielding reliable maps with an accuracy similar to intraoperative cortical mapping. Language mapping is also commonly performed, although nTMS language maps are not as highly concordant with direct intraoperative cortical stimulation maps as nTMS motor maps. Additionally, nTMS has been used to localize cortical regions involved in other functions such as facial recognition, calculation, higher-order motor processing, and visuospatial orientation. In this review, we evaluate the growing literature on the applications of nTMS in the preoperative setting. First, we analyze the evidence in support of the most common clinical applications. Then we identify usages that show promise but require further validation. We also discuss developing nTMS techniques that are still in the experimental stage, such as the use of nTMS to enhance postoperative recovery. Finally, we highlight practical considerations when utilizing nTMS and, importantly, its safety profile in neurosurgical patients. In so doing, we aim to provide a comprehensive review of the role of nTMS in the neurosurgical management of a patient with a brain tumor.

Value of aggressive surgical and intensive care unit in elderly patients with traumatic spinal cord injury

OBJECTIVEThe elderly are a growing subpopulation within traumatic spinal cord injury (SCI) patients. Studies have reported high morbidity and mortality rates in elderly patients who undergo surgery for SCI. In this study, the authors compare the perioperative outcomes of surgically managed elderly SCI patients with those of a younger cohort and those reported in the literature.METHODSData on a consecutive series of adult traumatic SCI patients surgically managed at a single institution in the period from 2007 to 2017 were retrospectively reviewed. The cohort was divided into two groups based on age: younger than 70 years and 70 years or older. Assessed outcomes included complications, in-hospital mortality, intensive care unit (ICU) stay, hospital length of stay (LOS), disposition, and neurological status.RESULTSA total of 106 patients were included in the study: 83 young and 23 elderly. The two groups were similar in terms of imaging features (cord hemorrhage and fracture), operative technique, and American Spinal Injury Association Impairment Scale (AIS) grade. The elderly had a significantly higher proportion of cervical SCIs (95.7% vs 71.1%, p = 0.047). There were no significant differences between the young and the elderly in terms of the ICU stay (13.1 vs 13.3 days, respectively, p = 0.948) and hospital LOS (23.3 vs 21.7 days, p = 0.793). Elderly patients experienced significantly higher complication (73.9% vs 43.4%, p = 0.010) and mortality (13.0% vs 1.2%, p = 0.008) rates; in other words, the elderly patients had 1.7 times and 10.8 times the rate of complications and mortality, respectively, than the younger patients. No elderly patients were discharged home (0.0% vs 18.1%, p = 0.029). Discharge AIS grade and AIS grade change were similar between the groups.CONCLUSIONSElderly patients had higher complication and mortality rates than those in younger patients and were less likely to be discharged home. However, it does seem that mortality rates have improved compared to those in prior historical reports.

Motor Cortical Network Plasticity in Patients With Recurrent Brain Tumors

Objective: The adult brain’s potential for plastic reorganization is an important mechanism for the preservation and restoration of function in patients with primary glial neoplasm. Patients with recurrent brain tumors requiring multiple interventions over time present an opportunity to examine brain reorganization. Magnetoencephalography (MEG) is a noninvasive imaging modality that can be used for motor cortical network mapping which, when performed at regular intervals, offers insight into this process of reorganization. Utilizing MEG-based motor mapping, we sought to characterize the reorganization of motor cortical networks over time in a cohort of 78 patients with recurrent glioma.

Methods: MEG-based motor cortical maps were obtained by measuring event-related desynchronization (ERD) in ß-band frequency during unilateral index finger flexion. Each patient presented at our Department at least on two occasions for tumor resection due to tumor recurrence, and MEG-based motor mapping was performed as part of preoperative assessment before each surgical resection. Whole-brain activation patterns from first to second MEG scan (obtained before first and second surgery) were compared. Additionally, we calculated distances of activation peaks, which represent the location of the primary motor cortex (MC), to determine the magnitude of movement in motor eloquent areas between the first and second MEG scan. We also explored which demographic, anatomic, and pathological factors influence these shifts.

Results: The whole-brain activation motor maps showed a subtle movement of the primary MC from first to second timepoint, as was confirmed by the determination of motor activation peaks. The shift of ipsilesional MC was directly correlated with a frontal-parietal tumor location (p < 0.001), presence of motor deficits (p = 0.021), and with a longer period between MEG scans (p = 0.048). Also, a disengagement of wide areas in the contralesional (ipsilateral to finger movement) hemisphere at the second time point was observed.

Conclusions: MEG imaging is a sensitive method for depicting the plasticity of the motor cortical network. Although the location of the primary MC undergoes only subtle changes, appreciable shifts can occur in the setting of a stronger and longer impairment of the tumor on the MC. The ipsilateral hemisphere may serve as a reservoir for functional recovery.

The impact of high functional connectivity network hub resection on language task performance in adult low- and high-grade glioma

OBJECTIVE

Gliomas are intrinsic brain tumors with the hallmark of diffuse white matter infiltration, resulting in short- and long-range network dysfunction. Preoperative magnetoencephalography (MEG) can assist in maximizing the extent of resection while minimizing morbidity. While MEG has been validated in motor mapping, its role in speech mapping remains less well studied. The authors assessed how the resection of intraoperative electrical stimulation (IES)-negative, high functional connectivity (HFC) network sites, as identified by MEG, impacts language performance.

METHODS

Resting-state, whole-brain MEG recordings were obtained from 26 patients who underwent perioperative language evaluation and glioma resection that was guided by awake language and IES mapping. The functional connectivity of an individual voxel was determined by the imaginary coherence between the index voxel and the rest of the brain, referenced to its contralesional pair. The percentage of resected HFC voxels was correlated with postoperative language outcomes in tasks of increasing complexity: text reading, 4-syllable repetition, picture naming, syntax (SYN), and auditory stimulus naming (AN).

RESULTS

Overall, 70% of patients (14/20) in whom any HFC tissue was resected developed an early postoperative language deficit (mean 2.3 days, range 1-8 days), compared to 33% of patients (2/6) in whom no HFC tissue was resected (p = 0.16). When bifurcated by the amount of HFC tissue that was resected, 100% of patients (3/3) with an HFC resection > 25% displayed deficits in AN, compared to 30% of patients (6/20) with an HFC resection < 25% (p = 0.04). Furthermore, there was a linear correlation between the severity of AN and SYN decline with percentage of HFC sites resected (p = 0.02 and p = 0.04, respectively). By 2.2 months postoperatively (range 1-6 months), the correlation between HFC resection and both AN and SYN decline had resolved (p = 0.94 and p = 1.00, respectively) in all patients (9/9) except two who experienced early postoperative tumor progression or stroke involving inferior frontooccipital fasciculus.

CONCLUSIONS

Imaginary coherence measures of functional connectivity using MEG are able to identify HFC network sites within and around low- and high-grade gliomas. Removal of IES-negative HFC sites results in early transient postoperative decline in AN and SYN, which resolved by 3 months in all patients without stroke or early tumor progression. Measures of functional connectivity may therefore be a useful means of counseling patients about postoperative risk and assist with preoperative surgical planning.

Pediatric firearm-related traumatic brain injury in United States trauma centers

OBJECTIVE

Pediatric firearm injury is a leading cause of death and disability in the youth of the United States. The epidemiology of and outcomes following gunshot wounds to the head (GSWHs) are in need of systematic characterization. Here, the authors analyzed pediatric GSWHs from a population-based sample to identify predictors of prolonged hospitalization, morbidity, and death.

METHODS

All patients younger than 18 years of age and diagnosed with a GSWH in the National Sample Program (NSP) of the National Trauma Data Bank (NTDB) in 2003-2012 were eligible for inclusion in this study. Variables of interest included injury intent, firearm type, site of incident, age, sex, race, health insurance, geographic region, trauma center level, isolated traumatic brain injury (TBI), hypotension in the emergency department, Glasgow Coma Scale (GCS) score, and Injury Severity Score (ISS). Risk predictors for a prolonged hospital stay, morbidity, and mortality were identified. Odds ratios, mean increases or decreases (B), and 95% confidence intervals were reported. Statistical significance was assessed at α < 0.001 accounting for multiple comparisons.

RESULTS

In a weighted sample of 2847 pediatric patients with GSWHs, the mean age was 14.8 ± 3.3 years, 79.2% were male, and 59.0% had severe TBI (GCS score 3-8). The mechanism of assault (63.0%), the handgun as firearm (45.6%), and an injury incurred in a residential area (40.6%) were most common. The mean hospital length of stay was 11.6 ± 14.4 days for the survivors, for whom suicide injuries involved longer hospitalizations (B = 5.9-day increase, 95% CI 3.3-8.6, p < 0.001) relative to those for accidental injuries. Mortality was 45.1% overall but was greater with injury due to suicidal intent (mortality 71.5%, p < 0.001) or caused by a shotgun (mortality 56.5%, p < 0.001). Lower GCS scores, higher ISSs, and emergency room hypotension predicted poorer outcomes. Patients with private insurance had lower mortality odds than those with Medicare/Medicaid (OR 2.4, 95% CI 1.7-3.4, p < 0.001) or government insurance (OR 3.6, 95% CI 2.2-5.8, p < 0.001). Management at level II centers, compared to level I, was associated with lower odds of returning home (OR 0.3, 95% CI 0.2-0.5, p < 0.001).

CONCLUSIONS

From 2003 to 2012, with regard to pediatric TBI hospitalizations due to GSWHs, their proportion remained stable, those caused by accidental injuries decreased, and those attributable to suicide increased. Overall mortality was 45%. Hypotension, cranial and overall injury severity, and suicidal intent were associated with poor prognoses. Patients treated at level II trauma centers had lower odds of being discharged home. Given the spectrum of risk factors that predispose children to GSWHs, emphasis on screening, parental education, and standardization of critical care management is needed to improve outcomes.

Pediatric Firearm-Related Traumatic Brain Injury in United States Trauma Centers

INTRODUCTION

Firearm injury is a leading cause of death and disability in the American youth. Epidemiology and outcomes following gunshot wound to the head (GSWH) are in need of systematic characterization. Here, we analyzed pediatric GSWH to identify predictors of prolonged hospitalization, morbidity and mortality.

METHODS

All patients < 18 yr with GSWH in the National Sample Program (NSP) of the National Trauma Data Bank (NTDB) from 2003 to 2012 were identified. Variables included injury intent, firearm choice, injury site, age, sex, race, health insurance, geographic region, trauma center level, isolated TBI, emergency department (ED) hypotension, Glasgow Coma Scale (GCS), and Injury Severity Score (ISS). Outcomes were hospital length of stay (HLOS), morbidity and mortality. Odds ratios (OR), mean increase/decrease (B), and 95% confidence intervals (CI) were reported. Statistical significance was assessed at a < 0.001 accounting for multiple comparisons.

RESULTS

In a weighted sample of 2847 pediatric GSWHs, age was 14.8 ± 3.3 yr, 79.2% were male, and 59.0% had severe traumatic brain injury (TBI; Glasgow Coma Scale [GCS] score 3-8). Assault (63.0%), handgun as firearm (45.6%), and injury in residential areas (40.6%) were most common. HLOS was 11.6 ± 14.4 d for the survivors, for which suicide injuries had longer hospitalization (B = 5.9 day increase, 95% CI [3.3-8.6], P < .001) relative to accidents. The overall mortality was 45.1%, and was greater with suicide intent (mortality = 71.5%, P < .001) and shotgun as firearm (mortality = 56.5%, P < .001). Lower GCS, higher ISS, and hypotension predicted poorer outcomes. Management at level II centers was associated with lower odds of returning home (OR = 0.3, [0.2-0.5], P < .001).

CONCLUSION

From 2003 to 2012, the proportion of accidental injuries decreased while suicides increased. The overall mortality was 45%, with hypotension, cranial and overall injury severity, and suicide intent being associated with poor prognosis. Patients treated at level II trauma centers had lower odds of being discharged home. Improved risk screening, parental education and standardization of critical care management are needed.

MEG imaging of recurrent gliomas reveals functional plasticity of hemispheric language specialization

In patients with gliomas, changes in hemispheric specialization for language determined by magnetoencephalography (MEG) were analyzed to elucidate the impact of treatment and tumor recurrence on language networks. Demonstration of reorganization of language networks in these patients has significant implications on the prevention of postoperative functional loss and recovery. Whole-brain activity during an auditory verb generation task was estimated from MEG recordings in a group of 73 patients with recurrent gliomas. Hemisphere of language dominance was estimated using the language laterality index (LI), a measure derived from the task. The initial scan was performed prior to resection; patients subsequently underwent surgery and adjuvant treatment. A second scan was performed upon recurrence prior to repeat resection. The relationship between the shift in LI between scans and demographics, anatomic location, pathology, and adjuvant treatment was analyzed. Laterality shifts were observed between scans; the median percent change was 29.1% across all patients. Laterality shift magnitude and relative direction were associated with the initial position of language dominance; patients with increased lateralization experienced greater shifts than those presenting more bilateral representation. A change in LI from left or right to bilateral (or vice versa) occurred in 23.3% of patients; complete switch occurred in 5.5% of patients. Patients with tumors within the language-dominant hemisphere experienced significantly greater shifts than those with contralateral tumors. The majority of patients with glioma experience shifts in language network organization over time which correlate with the relative position of language lateralization and tumor location.

Ultra-Early (<12 Hours) Surgery Correlates With Higher Rate of American Spinal Injury Association Impairment Scale Conversion After Cervical Spinal Cord Injury

BACKGROUND

Cervical spinal cord injury (SCI) is a devastating condition with very few treatment options. It remains unclear if early surgery correlated with conversion of American Spinal Injury Association Impairment Scale (AIS) grade A injuries to higher grades.

OBJECTIVE

To determine the optimal time to surgery after cervical SCI through retrospective analysis.

METHODS

We collected data from 48 patients with cervical SCI. Based on the time from Emergency Department (ED) presentation to surgical decompression, we grouped patients into ultra-early (decompression within 12 h of presentation), early (within 12-24 h), and late groups (&gt;24 h). We compared the improvement in AIS grade from admission to discharge, controlling for confounding factors such as AIS grade on admission, injury severity, and age. The mean time from injury to ED for this group of patients was 17 min.

RESULTS

Patients who received surgery within 12 h after presentation had a relative improvement in AIS grade from admission to discharge: the ultra-early group improved on average 1.3. AIS grades compared to 0.5 in the early group (P = .02). In addition, 88.8% of patients with an AIS grade A converted to a higher grade (AIS B or better) in the ultra-early group, compared to 38.4% in the early and late groups (P = .054).

CONCLUSION

These data suggest that surgical decompression after SCI that takes place within 12 h may lead to a relative improved neurological recovery compared to surgery that takes place after 12 h.

Adult Firearm-Related Traumatic Brain Injury in United States Trauma Centers

Civilian firearm injury is an important public health concern in the United States. Gunshot wounds to the head (GSWH) remain in need of update and systematic characterization. We identify predictors of prolonged hospital length of stay (HLOS), intensive care unit length of stay (ICU LOS), medical complications, mortality, and discharge disposition from a population-based sample using the National Sample Program (NSP) of the National Trauma Data Bank (NTDB), years 2003-2012. Statistical significance was assessed at α < 0.001 to correct for multiple comparisons. In total, 8148 adult GSWH patients were included extrapolating to 32,439 national incidents. Age was 36.6 ± 16.4 years and 64.4% were severe traumatic brain injury (TBI; Glasgow Coma Scale [GCS] score 3-8). Assault (49.2%), handgun (50.3%), and residential injury (43.2%) were of highest incidence. HLOS and ICU LOS were 7.7 ± 14.2 and 5.7 ± 13.4 days, respectively. Overall mortality was 54.6%; suicide/self-injury was associated with the highest mortality rate (71.6%). GCS, Injury Severity Score, and hypotension were significant predictors for outcomes overall. Medicare/Medicaid patients had longer HLOS compared to private/commercial insured (mean increase, 4.4 days; 95% confidence interval [2.6-6.3]). Compared to the Midwest, the South had longer HLOS (mean increase, 3.7 days; [2.0-5.4]) and higher odds of complications (odds ratio [OR], 1.7 [1.4-2.0]); the West had lower odds of complications (OR, 0.6; [0.5-0.7]). Versus handgun, shotgun (OR, 0.3; [0.2-0.4]) and hunting rifle (OR, 0.5; [0.4-0.8]) resulted in lower mortality. Patients with government/other insurance had higher odds of discharging home compared to private/commercially insured (OR, 1.7; [1.3-2.3]). In comparison to level I trauma centers, level II trauma centers had lower odds of discharge to home (OR, 0.7; [0.5-0.8]). Our results support hypotension, injury severity, injury intent, firearm type, and U.S. geographical location as important prognostic variables in firearm-related TBI. Improved understanding of civilian GSWH is critical to promoting increased awareness of firearm injuries as a public health concern and reducing its debilitating injury burden to patients, families, and healthcare systems.

Predictors of 30-Day Outcomes in Octogenarians with Traumatic C2 Fractures Undergoing Surgery

BACKGROUND

Predictors of surgical outcomes following traumatic axis (C2) fractures in octogenarians remain undercharacterized.

METHODS

Patients age ≥80 years undergoing cervical spine surgery following traumatic C2 fractures were extracted from the National Sample Program of the National Trauma Data Bank (2003-2012). Outcomes include overall inpatient complications, individual complications with an incidence >1%, hospital length of stay (HLOS), discharge disposition, and mortality. Demographics, comorbidities, and injury predictors were analyzed using multivariable regression. Odds ratios (OR), mean differences, and 95% confidence intervals (CIs) were calculated. Statistical significance was assessed at P < 0.05.

RESULTS

The cohort of 442 patients was 48.6% male and had a mean age of 84.3 ± 2.7 years. The distribution of admissions was 42.3% to the hospital floor, 40.3% to the intensive care unit (ICU), 7.7% to telemetry, 2.0% to the operating room, and 7.7% to other/unknown. Mortality was 9.7%, mean HLOS was 13.1 ± 9.2 days, the rate of complications was 38.5%, and 81.5% of survivors were discharged to a nonhome facility. Injury severity was predictive of mortality and overall complications. History of bleeding disorder/coagulopathy predicted mortality (OR, 4.02; 95% CI, 1.07-15.05), overall complications (OR, 3.01; 95% CI, 1.09-8.32), cardiac arrest (OR, 8.19; 95% CI, 1.06-63.54), and renal complications (OR, 10.36; 95% CI, 2.13-50.38). History of congestive heart failure predicted mortality (OR, 3.10; 95% CI, 1.10-8.69). ICU admission (vs. floor) predicted overall complications (OR, 2.01; 95% CI, 1.23-3.27) and pneumonia (OR, 4.65; 95% CI, 1.91-11.30). Telemetry admission (vs. floor) predicted unplanned intubation (OR, 7.76; 95% CI, 1.24-48.49).

CONCLUSIONS

In this cohort of octogenarians undergoing surgery for traumatic C2 fracture, injury severity and a history of bleeding disorder/coagulopathy were identified as risk factors for inpatient complications and mortality. Heightened surveillance should be considered for ICU and/or telemetry admissions for the development of complications. These findings warrant consideration by the clinician, patient, and family to inform clinical decisions and goals of care.

Apolipoprotein E epsilon 4 (APOE-ε4) genotype is associated with decreased 6-month verbal memory performance after mild traumatic brain injury

INTRODUCTION

The apolipoprotein E (APOE) ε4 allele associates with memory impairment in neurodegenerative diseases. Its association with memory after mild traumatic brain injury (mTBI) is unclear.

METHODS

mTBI patients (Glasgow Coma Scale score 13-15, no neurosurgical intervention, extracranial Abbreviated Injury Scale score ≤1) aged ≥18 years with APOE genotyping results were extracted from the Transforming Research and Clinical Knowledge in Traumatic Brain Injury Pilot (TRACK-TBI Pilot) study. Cohorts determined by APOE-ε4(+/-) were assessed for associations with 6-month verbal memory, measured by California Verbal Learning Test, Second Edition (CVLT-II) subscales: Immediate Recall Trials 1-5 (IRT), Short-Delay Free Recall (SDFR), Short-Delay Cued Recall (SDCR), Long-Delay Free Recall (LDFR), and Long-Delay Cued Recall (LDCR). Multivariable regression controlled for demographic factors, seizure history, loss of consciousness, posttraumatic amnesia, and acute intracranial pathology on computed tomography (CT).

RESULTS

In 114 mTBI patients (APOE-ε4(-)=79; APOE-ε4(+)=35), ApoE-ε4(+) was associated with long-delay verbal memory deficits (LDFR: B = -1.17 points, 95% CI [-2.33, -0.01], p = .049; LDCR: B = -1.58 [-2.63, -0.52], p = .004), and a marginal decrease on SDCR (B = -1.02 [-2.05, 0.00], p = .050). CT pathology was the strongest predictor of decreased verbal memory (IRT: B = -8.49, SDFR: B = -2.50, SDCR: B = -1.85, LDFR: B = -2.61, LDCR: B = -2.60; p < .001). Seizure history was associated with decreased short-term memory (SDFR: B = -1.32, p = .037; SDCR: B = -1.44, p = .038).

CONCLUSION

The APOE-ε4 allele may confer an increased risk of impairment of 6-month verbal memory for patients suffering mTBI, with implications for heightened surveillance and targeted therapies. Acute intracranial pathology remains the driver of decreased verbal memory performance at 6 months after mTBI.

Selective Serotonin Reuptake Inhibitors for Treating Neurocognitive and Neuropsychiatric Disorders Following Traumatic Brain Injury: An Evaluation of Current Evidence

The prevalence of neuropsychiatric disorders following traumatic brain injury (TBI) is 20%-50%, and disorders of mood and cognition may remain even after recovery of neurologic function is achieved. Selective serotonin reuptake inhibitors (SSRI) block the reuptake of serotonin in presynaptic cells to lead to increased serotonergic activity in the synaptic cleft, constituting first-line treatment for a variety of neurocognitive and neuropsychiatric disorders. This review investigates the utility of SSRIs in treating post-TBI disorders. In total, 37 unique reports were consolidated from the Cochrane Central Register and PubMed (eight randomized-controlled trials (RCTs), nine open-label studies, 11 case reports, nine review articles). SSRIs are associated with improvement of depressive but not cognitive symptoms. Pooled analysis using the Hamilton Depression Rating Scale demonstrate a significant mean decrease of depression severity following sertraline compared to placebo-a result supported by several other RCTs with similar endpoints. Evidence from smaller studies demonstrates mood improvement following SSRI administration with absent or negative effects on cognitive and functional recovery. Notably, studies on SSRI treatment effects for post-traumatic stress disorder after TBI remain absent, and this represents an important direction of future research. Furthermore, placebo-controlled studies with extended follow-up periods and concurrent biomarker, neuroimaging and behavioral data are necessary to delineate the attributable pharmacological effects of SSRIs in the TBI population.

Protocol for motor and language mapping by navigated TMS in patients and healthy volunteers; workshop report

INTRODUCTION

Navigated transcranial magnetic stimulation (nTMS) is increasingly used for preoperative mapping of motor function, and clinical evidence for its benefit for brain tumor patients is accumulating. In respect to language mapping with repetitive nTMS, literature reports have yielded variable results, and it is currently not routinely performed for presurgical language localization. The aim of this project is to define a common protocol for nTMS motor and language mapping to standardize its neurosurgical application and increase its clinical value.

METHODS

The nTMS workshop group, consisting of highly experienced nTMS users with experience of more than 1500 preoperative nTMS examinations, met in Helsinki in January 2016 for thorough discussions of current evidence and personal experiences with the goal to recommend a standardized protocol for neurosurgical applications.

RESULTS

nTMS motor mapping is a reliable and clinically validated tool to identify functional areas belonging to both normal and lesioned primary motor cortex. In contrast, this is less clear for language-eloquent cortical areas identified by nTMS. The user group agreed on a core protocol, which enables comparison of results between centers and has an excellent safety profile. Recommendations for nTMS motor and language mapping protocols and their optimal clinical integration are presented here.

CONCLUSION

At present, the expert panel recommends nTMS motor mapping in routine neurosurgical practice, as it has a sufficient level of evidence supporting its reliability. The panel recommends that nTMS language mapping be used in the framework of clinical studies to continue refinement of its protocol and increase reliability.

Safety and cost efficiency of a restrictive transfusion protocol in patients with traumatic brain injury

OBJECTIVE Blood loss and moderate anemia are common in patients with traumatic brain injury (TBI). However, despite evidence of the ill effects and expense of the transfusion of packed red blood cells, restrictive transfusion practices have not been universally adopted for patients with TBI. At a Level I trauma center, the authors compared patients with TBI who were managed with a restrictive (target hemoglobin level > 7 g/dl) versus a liberal (target hemoglobin level > 10 g/dl) transfusion protocol. This study evaluated the safety and cost-efficiency of a hospital-wide change to a restrictive transfusion protocol. METHODS A retrospective analysis of patients with TBI who were admitted to the intensive care unit (ICU) between January 2011 and September 2015 was performed. Patients < 16 years of age and those who died within 24 hours of admission were excluded. Demographic data and injury characteristics were compared between groups. Multivariable regression analyses were used to assess hospital outcome measures and mortality rates. Estimates from an activity-based cost analysis model were used to detect changes in cost with transfusion protocol. RESULTS A total of 1565 patients with TBI admitted to the ICU were included in the study. Multivariable analysis showed that a restrictive transfusion strategy was associated with fewer days of fever (p = 0.01) and that patients who received a transfusion had a larger fever burden. ICU length of stay, ventilator days, incidence of lung injury, thromboembolic events, and mortality rates were not significantly different between transfusion protocol groups. A restrictive transfusion protocol saved approximately $115,000 annually in hospital direct and indirect costs. CONCLUSIONS To the authors' knowledge, this is the largest study to date to compare transfusion protocols in patients with TBI. The results demonstrate that a hospital-wide change to a restrictive transfusion protocol is safe and cost-effective in patients with TBI.

Morbidity and Mortality Associated with Surgery of Traumatic C2 Fractures in Octogenarians

BACKGROUND: Management of axis fractures in the elderly remains controversial. As the US population increasingly lives past 80 years, published C2 fracture morbidity/mortality profiles in younger cohorts (55+) have become less applicable to octogenarians.

OBJECTIVE: To report associations between surgery and mortality, hospital length of stay and discharge disposition in octogenarians with traumatic C2 fractures.

METHODS: Retrospective cohort study of 3847 patients age ≥ 80 years representing 17 702 incidents nationwide, divided into surgery/nonsurgery cohorts, using the National Sample Program of the National Trauma Data Bank from 2003 to 2012. Inpatient complications, mortality, length of stay, and discharge disposition are characterized; multivariable regression was utilized to determine associations between surgery and outcomes.

Institutional Review Board (IRB): The National Sample Program dataset from the National Trauma Data Bank is fully deidentified and does not contain Health Insurance Portability and Accountability Act identifiers; therefore, this study is exempt from IRB review at the University of California, San Francisco.

RESULTS: Incidence of surgery was 10.3%. Surgery was associated with increased pneumonia, acute respiratory distress syndrome, and decubitus ulcer risks (P &lt; .001). Inpatient mortality was 12.8% (nonsurgery—13.0%; surgery—10.3%; P = .120). Length of stay was 8.31 ± 9.32 days (nonsurgery 7.78 ± 9.21; surgery 12.86 ± 9.07; P &lt; .001) and showed an adjusted mean increase of 5.68 days with surgery (95% confidence interval [4.74-6.61]). Of patients surviving to discharge, 26% returned home (nonsurgery—26.8%; surgery—18.8%; P = .001); surgery patients were less likely to return home (odds ratio 0.59 [0.44-0.78]).

CONCLUSION: The present study confirms that surgery of traumatic C2 fractures in octogenarians does not significantly affect inpatient mortality and increases discharge to institutionalized care. Patients undergoing surgery are more likely to require longer hospitalization and suffer increased medical complications during their stay. Given the retrospective nature of this study, it is unclear whether these conclusions reflect differences in injury severity between surgery cohorts. This question may be considered in a future prospective study.

Adult sports-related traumatic brain injury in United States trauma centers

OBJECTIVE Sports-related traumatic brain injury (TBI) is an important public health concern estimated to affect 300,000 to 3.8 million people annually in the United States. Although injuries to professional athletes dominate the media, this group represents only a small proportion of the overall population. Here, the authors characterize the demographics of sports-related TBI in adults from a community-based trauma population and identify predictors of prolonged hospitalization and increased morbidity and mortality rates. METHODS Utilizing the National Sample Program of the National Trauma Data Bank (NTDB), the authors retrospectively analyzed sports-related TBI data from adults (age ≥ 18 years) across 5 sporting categories-fall or interpersonal contact (FIC), roller sports, skiing/snowboarding, equestrian sports, and aquatic sports. Multivariable regression analysis was used to identify predictors of prolonged hospital length of stay (LOS), medical complications, inpatient mortality rates, and hospital discharge disposition. Statistical significance was assessed at α < 0.05, and the Bonferroni correction for multiple comparisons was applied for each outcome analysis. RESULTS From 2003 to 2012, in total, 4788 adult sports-related TBIs were documented in the NTDB, which represented 18,310 incidents nationally. Equestrian sports were the greatest contributors to sports-related TBI (45.2%). Mild TBI represented nearly 86% of injuries overall. Mean (± SEM) LOSs in the hospital or intensive care unit (ICU) were 4.25 ± 0.09 days and 1.60 ± 0.06 days, respectively. The mortality rate was 3.0% across all patients, but was statistically higher in TBI from roller sports (4.1%) and aquatic sports (7.7%). Age, hypotension on admission to the emergency department (ED), and the severity of head and extracranial injuries were statistically significant predictors of prolonged hospital and ICU LOSs, medical complications, failure to discharge to home, and death. Traumatic brain injury during aquatic sports was similarly associated with prolonged ICU and hospital LOSs, medical complications, and failure to be discharged to home. CONCLUSIONS Age, hypotension on ED admission, severity of head and extracranial injuries, and sports mechanism of injury are important prognostic variables in adult sports-related TBI. Increasing TBI awareness and helmet use-particularly in equestrian and roller sports-are critical elements for decreasing sports-related TBI events in adults.

Resection of Motor Eloquent Metastases Aided by Preoperative nTMS-Based Motor Maps-Comparison of Two Observational Cohorts

Introduction

Preoperative mapping of motor areas with navigated transcranial magnetic stimulation (nTMS) has been shown to improve surgical outcomes for peri-Rolandic lesions and, in particular, for gliomas. However, the impact of this technique on surgical outcomes for peri-Rolandic metastatic lesions is yet unknown.

Objective

To investigate the impact of nTMS on surgical outcomes for peri-Rolandic metastatic lesions, various clinical parameters were analyzed in our international study group.

Methods

Two prospectively enrolled cohorts were compared by investigating patients receiving preoperative nTMS (2010–2015; 120 patients) and patients who did not receive preoperative nTMS (2006–2015; 130 patients). Tumor location, pathology, size, and preoperative deficits were comparable.

Results

The nTMS group showed a lower rate of residual tumor on postoperative magnetic resonance imaging (odds ratio 0.3025; 95% confidence interval 0.1356–0.6749). On long-term follow-up, surgery-related paresis was decreased in the nTMS group (nTMS vs. non-nTMS; improved: 30.8 vs. 13.1%, unchanged: 65.8 vs. 73.8%, worse: 3.4 vs. 13.1% of patients; p = 0.0002). Moreover, the nTMS group received smaller craniotomies (nTMS: 16.7 ± 8.6 cm² vs. non-nTMS: 25.0 ± 17.1 cm²; p < 0.0001). Surgical time differed significantly between the two groups (nTMS: 128.8 ± 49.4 min vs. non-nTMS: 158.0 ± 65.8 min; p = 0.0002).

Conclusion

This non-randomized study suggests that preoperative motor mapping by nTMS may improve the treatment of patients undergoing surgical resection of metastases in peri-Rolandic regions. These findings suggest that further evaluation with a prospective, randomized trial may be warranted.

DRD2 C957T polymorphism is associated with improved 6-month verbal learning following traumatic brain injury

Traumatic brain injury (TBI) often leads to heterogeneous clinical outcomes, which may be influenced by genetic variation. A single-nucleotide polymorphism (SNP) in the dopamine D2 receptor (DRD2) may influence cognitive deficits following TBI. However, part of the association with DRD2 has been attributed to genetic variability within the adjacent ankyrin repeat and kinase domain containing 1 protein (ANKK1). Here, we utilize the Transforming Research and Clinical Knowledge in Traumatic Brain Injury Pilot (TRACK-TBI Pilot) study to investigate whether a novel DRD2 C957T polymorphism (rs6277) influences outcome on a cognitive battery at 6 months following TBI-California Verbal Learning Test (CVLT-II), Wechsler Adult Intelligence Test Processing Speed Index Composite Score (WAIS-PSI), and Trail Making Test (TMT). Results in 128 Caucasian subjects show that the rs6277 T-allele associates with better verbal learning and recall on CVLT-II Trials 1-5 (T-allele carrier 52.8 ± 1.3 points, C/C 47.9 ± 1.7 points; mean increase 4.9 points, 95% confidence interval [0.9 to 8.8]; p = 0.018), Short-Delay Free Recall (T-carrier 10.9 ± 0.4 points, C/C 9.7 ± 0.5 points; mean increase 1.2 points [0.1 to 2.5]; p = 0.046), and Long-Delay Free Recall (T-carrier 11.5 ± 0.4 points, C/C 10.2 ± 0.5 points; mean increase 1.3 points [0.1 to 2.5]; p = 0.041) after adjusting for age, education years, Glasgow Coma Scale, presence of acute intracranial pathology on head computed tomography scan, and genotype of the ANKK1 SNP rs1800497 using multivariable regression. No association was found between DRD2 C947T and non-verbal processing speed (WAIS-PSI) or mental flexibility (TMT) at 6 months. Hence, DRD2 C947T (rs6277) may be associated with better performance on select cognitive domains independent of ANKK1 following TBI.

Circadian variability of the initial Glasgow Coma Scale score in traumatic brain injury patients

Introduction

The Glasgow Coma Scale (GCS) score is the primary method of assessing consciousness after traumatic brain injury (TBI), and the clinical standard for classifying TBI severity. There is scant literature discerning the influence of circadian rhythms or emergency department (ED) arrival hour on this important clinical tool.

Methods

Retrospective cohort analysis of adult patients suffering blunt TBI using the National Sample Program of the National Trauma Data Bank, years 2003–2006. ED arrival GCS score was characterized by midday (10 a.m.–4 p.m.) and midnight (12 a.m.–6 a.m.) cohorts (N=24548). Proportions and standard errors are reported for descriptive data. Multivariable regressions using odds ratios (OR), mean differences (B), and their associated 95% confidence intervals [CI] were performed to assess associations between ED arrival hour and GCS score. Statistical significance was assessed at p<0.05.

Results

Patients were 42.48±0.13-years-old and 69.5% male. GCS score was 12.68±0.13 (77.2% mild, 5.2% moderate, 17.6% severe-TBI). Overall, patients were injured primarily via motor vehicle accidents (52.2%) and falls (24.2%), and 85.7% were admitted to hospital (33.5% ICU). Injury severity score did not differ between day and nighttime admissions.

Nighttime admissions associated with decreased systemic comorbidities (p<0.001) and increased likelihood of alcohol abuse and drug intoxication (p<0.001). GCS score demonstrated circadian rhythmicity with peak at 12 p.m. (13.03±0.08) and nadir at 4am (12.12±0.12). Midnight patients demonstrated lower GCS (12 a.m.–6 a.m.: 12.23±0.04; 10 a.m.–4 p.m.: 12.95±0.03, p<0.001). Multivariable regression adjusted for demographic and injury factors confirmed that midnight-hours independently associated with decreased GCS (B=−0.29 [−0.40, −0.19]).

In patients who did not die in ED or go directly to surgery (N=21862), midnight-hours (multivariable OR 1.73 [1.30–2.31]) associated with increased likelihood of ICU admission; increasing GCS score (per-unit OR 0.82 [0.80–0.83]) associated with decreased odds. Notably, the interaction factor ED GCS score*ED arrival hour independently demonstrated OR 0.96 [0.94–0.98], suggesting that the influence of GCS score on ICU admission odds is less important at night than during the day.

Conclusions

Nighttime TBI patients present with decreased GCS scores and are admitted to ICU at higher rates, yet have fewer prior comorbidities and similar systemic injuries. The interaction between nighttime hours and decreased GCS score on ICU admissions has important implications for clinical assessment/triage.

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Glasgow Coma Scale (GCS) score demonstrates circadian rhythmicity following TBI.

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Midnight-hours (12 a.m.–6 a.m.) independently associate with decreased GCS score.

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Midnight-hours independently associate with increased likelihood of ICU admission.

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Influence of GCS score on ICU admission is less important at night than in daytime.

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Nighttime TBIs present with less systemic comorbidities&increased substance use.

Perioperative morbidity and mortality after lumbar trauma in the elderly

OBJECT Traumatic fractures of the thoracolumbar spine are common injuries, accounting for approximately 90% of all spinal trauma. Lumbar spine trauma in the elderly is a growing public health problem with relatively little evidence to guide clinical management. The authors sought to characterize the complications, morbidity, and mortality associated with surgical and nonsurgical management in elderly patients with traumatic fractures of the lumbar spine. METHODS Using the National Sample Program of the National Trauma Data Bank, the authors performed a retrospective analysis of patients ≥ 55 years of age who had traumatic fracture to the lumbar spine. This group was divided into middle-aged (55-69 years) and elderly (≥ 70 years) cohorts. Cohorts were subdivided into nonoperative, vertebroplasty or kyphoplasty, noninstrumented surgery, and instrumented surgery. Univariate and multivariable analyses were used to characterize and identify predictors of medical and surgical complications, mortality, hospital length of stay, ICU length of stay, number of days on ventilator, and hospital discharge in each subgroup. Adjusted odds ratios, mean differences, and associated 95% CIs were reported. Statistical significance was assessed at p < 0.05, and the Bonferroni correction for multiple comparisons was applied for each outcome analysis. RESULTS Between 2003 and 2012, 22,835 people met the inclusion criteria, which represents 94,103 incidents nationally. Analyses revealed a similar medical and surgical complication profile between age groups. The most prevalent medical complications were pneumonia (7.0%), acute respiratory distress syndrome (3.6%), and deep venous thrombosis (3%). Surgical site infections occurred in 6.3% of cases. Instrumented surgery was associated with the highest odds of each complication (p < 0.001). The inpatient mortality rate was 6.8% for all subjects. Multivariable analyses demonstrated that age ≥ 70 years was an independent predictor of mortality (OR 3.16, 95% CI 2.77-3.60), whereas instrumented surgery (multivariable OR 0.38, 95% CI 0.28-0.52) and vertebroplasty or kyphoplasty (OR 0.27, 95% CI 0.17-0.45) were associated with decreased odds of death. In surviving patients, both older age (OR 0.32, 95% CI 0.30-0.34) and instrumented fusion (OR 0.37, 95% CI 0.33-0.41) were associated with decreased odds of discharge to home. CONCLUSIONS The present study confirms that lumbar surgery in the elderly is associated with increased morbidity. In particular, instrumented fusion is associated with periprocedural complications, prolonged hospitalization, and a decreased likelihood of being discharged home. However, fusion surgery is also associated with reduced mortality. Age alone should not be an exclusionary factor in identifying surgical candidates for instrumented lumbar spinal fusion. Future studies are needed to confirm these findings.

Pediatric sports-related traumatic brain injury in United States trauma centers

OBJECTIVE

Traumatic brain injury (TBI) in children is a significant public health concern estimated to result in over 500,000 emergency department (ED) visits and more than 60,000 hospitalizations in the United States annually. Sports activities are one important mechanism leading to pediatric TBI. In this study, the authors characterize the demographics of sports-related TBI in the pediatric population and identify predictors of prolonged hospitalization and of increased morbidity and mortality rates.

METHODS

Utilizing the National Sample Program of the National Trauma Data Bank (NTDB), the authors retrospectively analyzed sports-related TBI data from children (age 0–17 years) across 5 sports categories: fall or interpersonal contact (FIC), roller sports, skiing/snowboarding, equestrian sports, and aquatic sports. Multivariable regression analysis was used to identify predictors of prolonged length of stay (LOS) in the hospital or intensive care unit (ICU), medical complications, inpatient mortality rates, and hospital discharge disposition. Statistical significance was assessed at α < 0.05, and the Bonferroni correction (set at significance threshold p = 0.01) for multiple comparisons was applied in each outcome analysis.

RESULTS

From 2003 to 2012, in total 3046 pediatric sports-related TBIs were recorded in the NTDB, and these injuries represented 11,614 incidents nationally after sample weighting. Fall or interpersonal contact events were the greatest contributors to sports-related TBI (47.4%). Mild TBI represented 87.1% of the injuries overall. Mean (± SEM) LOSs in the hospital and ICU were 2.68 ± 0.07 days and 2.73 ± 0.12 days, respectively. The overall mortality rate was 0.8%, and the prevalence of medical complications was 2.1% across all patients. Severities of head and extracranial injuries were significant predictors of prolonged hospital and ICU LOSs, medical complications, failure to discharge to home, and death. Hypotension on admission to the ED was a significant predictor of failure to discharge to home (OR 0.05, 95% CI 0.03–0.07, p < 0.001). Traumatic brain injury incurred during roller sports was independently associated with prolonged hospital LOS compared with FIC events (mean increase 0.54 ± 0.15 days, p < 0.001).

CONCLUSIONS

In pediatric sports-related TBI, the severities of head and extracranial traumas are important predictors of patients developing acute medical complications, prolonged hospital and ICU LOSs, in-hospital mortality rates, and failure to discharge to home. Acute hypotension after a TBI event decreases the probability of successful discharge to home. Increasing TBI awareness and use of head-protective gear, particularly in high-velocity sports in older age groups, is necessary to prevent pediatric sports-related TBI or to improve outcomes after a TBI.

The sensitivity and significance of lateralized interictal slow activity on magnetoencephalography in focal epilepsy

OBJECTIVE

Asymmetric large-amplitude slow activity is sometimes observed on interictal electroencephalography (EEG) in epilepsy. However, few studies have examined slowing during magnetoencephalography (MEG) recordings, which are performed primarily to localize interictal spikes. Also, no prior investigations have compared the sensitivity of MEG to scalp EEG in detecting slow rhythms.

METHODS

We performed a retrospective cohort study of focal epilepsy patients who received MEG followed by surgical resection at our institution. We examined MEG, simultaneous EEG, and long-term EEG recordings for prominent asymmetric slow activity (delta-range, 1-4 Hz), and evaluated post-operative seizure outcomes.

RESULTS

We studied 132 patients with ≥ 1 year post-operative follow-up (mean, 3.6 years). Mean age was 27 (range, 3-68) years, and 55% of patients were male. Asymmetric large-amplitude slow wave activity was observed on interictal MEG in 21 of 132 (16%) patients. Interictal slowing lateralized to the hemisphere of resection in all but one (95%) patient. Among the 21 patients with interictal MEG slowing, 11 (52%) individuals had similarly lateralized EEG slowing, 7 patients had no EEG slowing, and 3 had bilateral symmetric EEG slowing. Meanwhile, none of the 111 patients without lateralized MEG slowing had asymmetric EEG slowing, suggesting significantly higher sensitivity of MEG versus EEG in detecting asymmetric slowing (χ(2)=63.4, p<0.001). MEG slowing was associated with shorter epilepsy duration with an odds ratio of 5.4 (1.7-17.0, 95% confidence interval). At last follow-up, 92 (70%) patients were seizure free (Engel I outcome), with no difference in seizure freedom rates between patients with (71%) or without (69%) asymmetric MEG slowing (χ(2)=0.4, p=0.99).

SIGNIFICANCE

MEG has higher sensitivity than scalp EEG in detecting asymmetric slow activity in focal epilepsy, which reliably lateralizes to the epileptogenic hemisphere. Other uses of MEG beyond spike localization may further improve presurgical evaluations in epilepsy.

Direct visualization of improved optic nerve pial vascular supply following tuberculum meningioma resection: case report

Tuberculum sellae meningiomas frequently produce visual loss by direct compression from tumor, constriction of the optic nerve (ON) under the falciform ligament, and/or ON ischemia. The authors hypothesized that changes in visual function after tumor removal may be related to changes in blood supply to the ON that might be seen in the pial circulation at surgery. Indocyanine green (ICG) angiography was used to attempt to document these changes at surgery. The first patient in whom the technique was used had a left-sided, 1.4-cm, tuberculum meningioma. Time-lapse comparison of images was done postsurgery, and the comparison of video images revealed both faster initial filling and earlier complete filling of the ON pial circulation, suggesting improved pial blood flow after surgical decompression. In follow-up the patient had significant improvements in both visual acuity and visual fields function. Intraoperative ICG angiography of the ON can demonstrate measurable changes in pial vascular flow that may be predictive of postoperative visual outcome. The predictive value of this technique during neurosurgical procedures around the optic apparatus warrants further investigation in a larger cohort.

COMT Val 158 Met polymorphism is associated with nonverbal cognition following mild traumatic brain injury

Mild traumatic brain injury (mTBI) results in variable clinical outcomes, which may be influenced by genetic variation. A single-nucleotide polymorphism in catechol-o-methyltransferase (COMT), an enzyme which degrades catecholamine neurotransmitters, may influence cognitive deficits following moderate and/or severe head trauma. However, this has been disputed, and its role in mTBI has not been studied. Here, we utilize the Transforming Research and Clinical Knowledge in Traumatic Brain Injury Pilot (TRACK-TBI Pilot) study to investigate whether the COMT Val (158) Met polymorphism influences outcome on a cognitive battery 6 months following mTBI--Wechsler Adult Intelligence Test Processing Speed Index Composite Score (WAIS-PSI), Trail Making Test (TMT) Trail B minus Trail A time, and California Verbal Learning Test, Second Edition Trial 1-5 Standard Score (CVLT-II). All patients had an emergency department Glasgow Coma Scale (GCS) of 13-15, no acute intracranial pathology on head CT, and no polytrauma as defined by an Abbreviated Injury Scale (AIS) score of ≥3 in any extracranial region. Results in 100 subjects aged 40.9 (SD 15.2) years (COMT Met (158) /Met (158) 29 %, Met (158) /Val (158) 47 %, Val (158) /Val (158) 24 %) show that the COMT Met (158) allele (mean 101.6 ± SE 2.1) associates with higher nonverbal processing speed on the WAIS-PSI when compared to Val (158) /Val (158) homozygotes (93.8 ± SE 3.0) after controlling for demographics and injury severity (mean increase 7.9 points, 95 % CI [1.4 to 14.3], p = 0.017). The COMT Val (158) Met polymorphism did not associate with mental flexibility on the TMT or with verbal learning on the CVLT-II. Hence, COMT Val (158) Met may preferentially modulate nonverbal cognition following uncomplicated mTBI.Registry: ClinicalTrials.gov Identifier NCT01565551.