Traumatic Cerebral Microbleeds in the Subacute Phase Are Practical and Early Predictors of Abnormality of the Normal-Appearing White Matter in the Chronic Phase

BACKGROUND AND PURPOSE

In the chronic phase after traumatic brain injury, DTI findings reflect WM integrity. DTI interpretation in the subacute phase is less straightforward. Microbleed evaluation with SWI is straightforward in both phases. We evaluated whether the microbleed concentration in the subacute phase is associated with the integrity of normal-appearing WM in the chronic phase.

MATERIALS AND METHODS

Sixty of 211 consecutive patients 18 years of age or older admitted to our emergency department ≤24 hours after moderate to severe traumatic brain injury matched the selection criteria. Standardized 3T SWI, DTI, and T1WI were obtained 3 and 26 weeks after traumatic brain injury in 31 patients and 24 healthy volunteers. At baseline, microbleed concentrations were calculated. At follow-up, mean diffusivity (MD) was calculated in the normal-appearing WM in reference to the healthy volunteers (MD_z). Through linear regression, we evaluated the relation between microbleed concentration and MD_z in predefined structures.

RESULTS

In the cerebral hemispheres, MD_z at follow-up was independently associated with the microbleed concentration at baseline (left: B = 38.4 [95% CI 7.5-69.3], P = .017; right: B = 26.3 [95% CI 5.7-47.0], P = .014). No such relation was demonstrated in the central brain. MD_z in the corpus callosum was independently associated with the microbleed concentration in the structures connected by WM tracts running through the corpus callosum (B = 20.0 [95% CI 24.8-75.2], P < .000). MD_z in the central brain was independently associated with the microbleed concentration in the cerebral hemispheres (B = 25.7 [95% CI 3.9-47.5], P = .023).

CONCLUSIONS

SWI-assessed microbleeds in the subacute phase are associated with DTI-based WM integrity in the chronic phase. These associations are found both within regions and between functionally connected regions.

Safety and efficacy of Cerebrolysin in acute brain injury and neurorecovery: CAPTAIN I-a randomized, placebo-controlled, double-blind, Asian-Pacific trial

OBJECTIVE

To evaluate the safety and efficacy of Cerebrolysin as an add-on therapy to local standard treatment protocol in patients after moderate-to-severe traumatic brain injury.

METHODS

The patients received the study medication in addition to standard care (50 mL of Cerebrolysin or physiological saline solution daily for 10 days, followed by two additional treatment cycles with 10 mL daily for 10 days) in a prospective, randomized, double-blind, placebo-controlled, parallel-group, multi-centre phase IIIb/IV trial. The primary endpoint was a multidimensional ensemble of 14 outcome scales pooled to be analyzed by means of the multivariate, correlation-sensitive Wei-Lachin procedure.

RESULTS

In 46 enrolled TBI patients (Cerebrolysin 22, placebo 24), three single outcomes showed stand-alone statistically significant superiority of Cerebrolysin [Stroop Word/Dots Interference (p = 0.0415, Mann-Whitney(MW) = 0.6816, 95% CI 0.51-0.86); Color Trails Tests 1 and 2 (p = 0.0223/0.0170, MW = 0.72/0.73, 95% CI 0.53-0.90/0.54-0.91), both effect sizes lying above the benchmark for "large" superiority (MW > 0.71)]. While for the primary multivariate ensemble, statistical significance was just missed in the intention-to-treat population (p_Wei-Lachin < 0.1, MW_combined = 0.63, 95% CI 0.48-0.77, derived standardized mean difference (SMD) 0.45, 95% CI -0.07 to 1.04, derived OR 2.1, 95% CI 0.89-5.95), the per-protocol analysis showed a statistical significant superiority of Cerebrolysin (p_Wei-Lachin = 0.0240, MW_combined = 0.69, 95% CI 0.53 to 0.85, derived SMD 0.69, 95% CI 0.09 to 1.47, derived OR 3.2, 95% CI 1.16 to 12.8), with effect sizes of six single outcomes lying above the benchmark for "large" superiority. Safety aspects were comparable to placebo.

CONCLUSION

Our trial suggests beneficial effects of Cerebrolysin on outcome after TBI. Results should be confirmed by a larger RCT with a comparable multidimensional approach.

Association of Very Early Serum Levels of S100B, Glial Fibrillary Acidic Protein, Ubiquitin C-Terminal Hydrolase-L1, and Spectrin Breakdown Product with Outcome in ProTECT III

Rapid risk-stratification of patients with acute traumatic brain injury (TBI) would inform management decisions and prognostication. The objective of this serum biomarker study (Biomarkers of Injury and Outcome [BIO]-Progesterone for Traumatic Brain Injury, Experimental Clinical Treatment [ProTECT]) was to test the hypothesis that serum biomarkers of structural brain injury, measured at a single, very early time-point, add value beyond relevant clinical covariates when predicting unfavorable outcome 6 months after moderate-to-severe acute TBI. BIO-ProTECT utilized prospectively collected samples obtained from subjects with moderate-to-severe TBI enrolled in the ProTECT III clinical trial of progesterone. Serum samples were obtained within 4 h after injury. Glial fibrillary acidic protein (GFAP), S100B, αII-spectrin breakdown product of molecular weight 150 (SBDP150), and ubiquitin C-terminal hydrolase-L1 (UCH-L1) were measured. The association between log-transformed biomarker levels and poor outcome, defined by a Glasgow Outcome Scale-Extended (GOS-E) score of 1-4 at 6 months post-injury, were estimated via logistic regression. Prognostic models and a biomarker risk score were developed using bootstrapping techniques. Of 882 ProTECT III subjects, samples were available for 566. Each biomarker was associated with 6-month GOS-E (p < 0.001). Compared with a model containing baseline patient variables/characteristics, inclusion of S100B and GFAP significantly improved prognostic capacity (p ≤ 0.05 both comparisons); conversely, UCH-L1 and SBDP did not. A final predictive model incorporating baseline patient variables/characteristics and biomarker data (S100B and GFAP) had the best prognostic capability (area under the curve [AUC] = 0.85, 95% confidence interval [CI]: CI 0.81-0.89). Very early measurements of brain-specific biomarkers are independently associated with 6-month outcome after moderate-to-severe TBI and enhance outcome prediction.

The association between post-concussion symptoms and health-related quality of life in patients with mild traumatic brain injury

A subset of mild traumatic brain injury (mTBI) patients experience post-concussion symptoms. When a cluster of post-concussion symptoms persists for over three months, it is referred to as post-concussion syndrome (PCS). Little is known about the association between PCS and Health-Related Quality of Life (HRQoL) after mTBI. The aims of this study were to assess the implications of PCS on HRQoL six months after mTBI and the relationship between PCS and HRQoL domains. A prospective observational cohort study was conducted among a sample of mTBI patients. Follow-up postal questionnaires at six months after emergency department (ED) admission included socio-demographic information, the Rivermead Post-Concussion Symptoms Questionnaire (RPQ), and HRQoL measured with the 36-item Short-Form Health Survey (SF-36) and the Perceived Quality of Life Scale (PQoL). In total, 731 mTBI patients were included, of whom 38.7% were classified as suffering from PCS. Patients with PCS had significantly lower scores on all SF-36 domains, lower physical and mental component summary scores and lower mean PQoL scores compared to patients without PCS. All items of the RPQ were negatively correlated to all SF-36 domains and PQoL subscale scores, indicating that reporting problems on any of the RPQ symptoms was associated with a decrease on different aspects of an individuals' HRQoL. To conclude, PCS is common following mTBI and patients with PCS have a considerably lower HRQoL. A better understanding of the relationship between PCS and HRQoL and possible mediating factors in this relationship could improve intervention strategies, the recovery process for mTBI patients and benchmarking.

Adjusting for confounding by indication in observational studies: a case study in traumatic brain injury

INTRODUCTION

Observational studies of interventions are at risk for confounding by indication. The objective of the current study was to define the circumstances for the validity of methods to adjust for confounding by indication in observational studies.

PATIENTS AND METHODS

We performed post hoc analyses of data prospectively collected from three European and North American traumatic brain injury studies including 1,725 patients. The effects of three interventions (intracranial pressure [ICP] monitoring, intracranial operation and primary referral) were estimated in a proportional odds regression model with the Glasgow Outcome Scale as ordinal outcome variable. Three analytical methods were compared: classical covariate adjustment, propensity score matching and instrumental variable (IV) analysis in which the percentage exposed to an intervention in each hospital was added as an independent variable, together with a random intercept for each hospital. In addition, a simulation study was performed in which the effect of a hypothetical beneficial intervention (OR 1.65) was simulated for scenarios with and without unmeasured confounders.

RESULTS

For all three interventions, covariate adjustment and propensity score matching resulted in negative estimates of the treatment effect (OR ranging from 0.80 to 0.92), whereas the IV approach indicated that both ICP monitoring and intracranial operation might be beneficial (OR per 10% change 1.17, 95% CI 1.01-1.42 and 1.42, 95% CI 0.95-1.97). In our simulation study, we found that covariate adjustment and propensity score matching resulted in an invalid estimate of the treatment effect in case of unmeasured confounders (OR ranging from 0.90 to 1.03). The IV approach provided an estimate in the similar direction as the simulated effect (OR per 10% change 1.04-1.05) but was statistically inefficient.

CONCLUSION

The effect estimation of interventions in observational studies strongly depends on the analytical method used. When unobserved confounding and practice variation are expected in observational multicenter studies, IV analysis should be considered.

Divergent Classification Methods of Post-Concussion Syndrome after Mild Traumatic Brain Injury: Prevalence Rates, Risk Factors, and Functional Outcome

Mild traumatic brain injury (mTBI) is a common diagnosis and approximately one third of mTBI patients experience a variety of cognitive, emotional, psychosocial, and behavioral post-concussion symptoms. When a cluster of these symptoms persists for more than 3 months they are often classified as post-concussion syndrome (PCS). The objective of this study was to determine prevalence rates, risk factors, and functional outcome associated with PCS 6 months after mTBI, applying divergent classification methods. Follow-up questionnaires at 6 months after mTBI included the Rivermead Post-Concussion Symptoms Questionnaire (RPQ) and the Glasgow Outcome Scale Extended (GOSE). The RPQ was analyzed according to different classification methods: the mapped International Classification of Diseases, 10th revision (ICD-10)/Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV), the RPQ total score, the RPQ3 and the three-factor model using two different cutoff points (mild or worse and moderate or worse). Our results from a sample of 731 mTBI patients showed that prevalence rates of PCS ranged from 11.4% to 38.7% using divergent classification methods. According to all eight methods, 6.3% (n = 46) of mTBI patients experienced PCS. Applying the divergent classification methods resulted in a different set of predictors being statistically significantly associated with PCS, and a different percentage of overlap with functional impairment, measured with the GOSE. In conclusion, depending on the classification method and rating score used, prevalence rates of PCS deviated considerably. For future research, consensus regarding the diagnostic criteria for PCS and the analysis of the RPQ should be reached, to enhance comparability of studies regarding PCS after mTBI.

What is the definition of sports-related concussion: a systematic review

OBJECTIVES

Various definitions for concussion have been proposed, each having its strengths and weaknesses. We reviewed and compared current definitions and identified criteria necessary for an operational definition of sports-related concussion (SRC) in preparation of the 5th Concussion Consensus Conference (Berlin, Germany). We also assessed the role of biomechanical studies in informing an operational definition of SRC.

DESIGN

This is a systematic literature review.

DATA SOURCES

Data sources include MEDLINE, Embase, Cumulative Index to Nursing and Allied Health Literature, Cochrane Central Register of Clinical Trials and SPORT Discus (accessed 14 September 2016).

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Eligibility criteria were studies reporting (clinical) criteria for diagnosing SRC and studies containing SRC impact data.

RESULTS

Out of 1601 articles screened, 36 studies were included (2.2%), 14 reported on criteria for SRC definitions and 22 on biomechanical aspects of concussions. Six different operational definitions focusing on clinical findings and their dynamics were identified. Biomechanical studies were obtained almost exclusively on American football players. Angular and linear head accelerations linked to clinically confirmed concussions demonstrated considerable individual variation.

SUMMARY/CONCLUSIONS

SRC is a traumatic brain injury that is defined as a complex pathophysiological process affecting the brain, induced by biomechanical forces with several common features that help define its nature. Limitations identified include that the current criteria for diagnosing SRC are clinically oriented and that there is no gold/standard to assess their diagnostic properties. A future, more valid definition of SRC would better identify concussed players by demonstrating high predictive positive/negative values. Currently, the use of helmet-based systems to study the biomechanics of SRC is limited to few collision sports. New approaches need to be developed to provide objective markers for SRC.

Comparing health-related quality of life of Dutch and Chinese patients with traumatic brain injury: do cultural differences play a role?

BACKGROUND

There is growing interest in health related quality of life (HRQoL) as an outcome measure in international trials. However, there might be differences in the conceptualization of HRQoL across different socio-cultural groups. The objectives of current study were: (I) to compare HRQoL, measured with the short form (SF)-36 of Dutch and Chinese traumatic brain injury (TBI) patients 1 year after injury and; (II) to assess whether differences in SF-36 profiles could be explained by cultural differences in HRQoL conceptualization. TBI patients are of particular interest because this is an important cause of diverse impairments and disabilities in functional, physical, emotional, cognitive, and social domains that may drastically reduce HRQoL.

METHODS

A prospective cohort study on adult TBI patients in the Netherlands (RUBICS) and a retrospective cohort study in China were used to compare HRQoL 1 year post-injury. Differences on subscales were assessed with the Mann-Whitney U-test. The internal consistency, interscale correlations, item-internal consistency and item-discriminate validity of Dutch and Chinese SF-36 profiles were examined. Confirmatory factor analysis was performed to assess whether Dutch and Chinese data fitted the SF-36 two factor-model (physical and mental construct).

RESULTS

Four hundred forty seven Dutch and 173 Chinese TBI patients were included. Dutch patients obtained significantly higher scores on role limitations due to emotional problems (p < .001) and general health (p < .001), while Chinese patients obtained significantly higher scores on physical functioning (p < .001) and bodily pain (p = .001). Scores on these subscales were not explained by cultural differences in conceptualization, since item- and scale statistics were all sufficient. However, differences among Dutch and Chinese patients were found in the conceptualization of the domains vitality, mental health and social functioning.

CONCLUSIONS

One year after TBI, Dutch and Chinese patients reported a different pattern of HRQoL. Further, there might be cultural differences in the conceptualization of some of the SF-36 subscales, which has implications for outcome evaluation in multi-national trials.

Effects of an Integrated 'Fast Track' Rehabilitation Service for Multi-Trauma Patients: A Non-Randomized Clinical Trial in the Netherlands

Objectives

The effects on health related outcomes of a newly-developed rehabilitation program, called ‘supported Fast Track multi-trauma rehabilitation service’ (Fast Track), were evaluated in comparison with conventional trauma rehabilitation service (Care as Usual).

Methods

Prospective, multi-center, non-randomized controlled study. Between 2009 and 2012, 132 adult multi-trauma patients were included: 65 Fast Track and 67 Care as Usual patients with an Injury Severity Score ≥16, complex multiple injuries in several extremities or complex pelvic and/or acetabulum fractures. The Fast Track program involved: integrated coordination between trauma surgeon and rehabilitation physician, shorter stay in hospital with faster transfer to a specialized trauma rehabilitation unit, earlier start of multidisciplinary treatment and ‘non-weight bearing’ mobilization. Primary outcomes were functional status (FIM) and quality of life (SF-36) measured through questionnaires at baseline, 3, 6, 9 and 12 months post-trauma. Outcomes were analyzed using a linear mixed-effects regression model.

Results

The FIM scores significantly increased between 0 and 3 months (p<0.001) for both groups showing that they had improved overall, and continued to improve between 3 and 6 months for Fast Track (p = 0.04) and between 3 and 9 months for Care as Usual (p = 0.03). SF-36 scores significantly improved in both groups between 3 and 6 months (Fast Track, p<0.001; Care as Usual, p = 0.01). At 12 months, SF-36 scores were still below (self-reported) baseline measurements of patient health prior to the accident. However, the FIM and SF-36 scores differed little between the groups at any of the measured time points.

Conclusion

Both Fast Track and Care as Usual rehabilitation programs were effective in that multi-trauma patients improved their functional status and quality of life. A faster (maximum) recovery in functional status was observed for Fast Track at 6 months compared to 9 months for Care as Usual. At twelve months follow-up no differential effects between treatment conditions were found.

Trial Registration

ISRCTN68246661

Brain injury severity and autonomic dysregulation accurately predict heterotopic ossification in patients with traumatic brain injury

Objective : To assess brain injury severity, autonomic dysregulation and systemic infection as risk factors for the occurrence of heterotopic ossification in patients with severe traumatic brain injury.

Design : Historic cohort study.

Setting : Radboud University Medical Centre.

Subjects : All consecutively admitted patients with severe traumatic brain injury (admission Glasgow Coma Scale score 8 or less) during the years 2002—2003.

Main measures : The development of clinically relevant heterotopic ossification, defined as painful swelling of joints with redness and decreased range of motion, confirmed radiographically.

Results : Seventy-six (64%) of the 119 patients survived and were eligible for further follow-up. Nine patients (12%) developed 20 symptomatic heterotopic ossifications, in one or more joints. Patients with heterotopic ossification had sustained more severe brain injuries, compared to the group without heterotopic ossification. The mean coma duration in the heterotopic ossification group was 28.11 days (SD 20.20) versus 7.54 days (SD 7.47) in the patients without heterotopic ossification (P < 0.001). The occurrence of autonomic dysregulation (relative risk (RR) 59.55, 95% confidence interval (CI) 8.39—422.36), diffuse axonal injury (RR 20.68, 95% CI 4.92—86.91), spasticity (RR 16.96, 95% CI 3.96—72.57) and systemic infection (RR 13.12, 95% CI 3.01—57.17) were all associated with an increased risk of developing symptomatic heterotopic ossification. However, only autonomic dysregulation had a high positive (88.9%, 95% CI 51.7—99.7) and negative (98.5%, 95% CI 91.9—99.9) predictive value with regard to heterotopic ossification.

Conclusions : The occurrence of autonomic dysregulation may predict the chance of developing heterotopic ossification in patients with severe head injury.

The vegetative state: prevalence, misdiagnosis, and treatment limitations

INTRODUCTION

Patients in a vegetative state/unresponsive wakefulness syndrome (VS/UWS) open their eyes spontaneously, but show only reflexive behavior. Although VS/UWS is one of the worst possible outcomes of acquired brain injury, its prevalence is largely unknown. This study's objective was to map the total population of hospitalized and institutionalized patients in VS/UWS in the Netherlands: prevalence, clinical characteristics, and treatment limitations.

METHODS

Nationwide point prevalence study on patients in VS/UWS at least 1 month after acute brain injury in hospitals, rehabilitation centers, nursing homes, institutions for people with intellectual disability, and hospices; diagnosis verification by a researcher using the Coma Recovery Scale-revised (CRS-r); gathering of demographics, clinical characteristics, and treatment limitations.

RESULTS

We identified 33 patients in VS/UWS, 24 of whose diagnoses could be verified. Patients were on average 51 years old with a mean duration of VS/UWS of 5 years. The main etiology was hypoxia sustained during cardiac arrest and resuscitation. More than 50% of patients had not received rehabilitation services. Most were given life-sustaining treatment beyond internationally accepted prognostic boundaries regarding recovery of consciousness. Seventeen (39%) of 41 patients presumed to be in VS/UWS were found to be at least minimally conscious.

CONCLUSIONS

Results translate to a prevalence of 0.1 to 0.2 hospitalized and institutionalized VS/UWS patients per 100,000 members of the general population. This small figure may be related to the legal option to withhold or withdraw life-sustaining treatment, including artificial nutrition and hydration. On the other hand, this study shows that in certain cases, physicians continue life-prolonging treatment for up to 25 years. Patients have poor access to rehabilitation and are at substantial risk for misdiagnosis.

The juvenile head trauma syndrome: a trauma triggered migraine?

BACKGROUND

The underlying mechanism of the juvenile head trauma syndrome (JHTS) is still uncertain, but it has been suggested that there is a role in cortical spreading depression, a phenomenon that is assumed to be a part of the pathophysiology of migraine.

HYPOTHESIS

We postulate that children affected by the JHTS are more susceptible to cortical spreading depression, caused by a genetic etiology similar to genetic factors in migraine.

METHODS

Children with the JHTS were selected and evaluated retrospectively in an observational case-control study in two Dutch trauma centers in the period between January 2008 and July 2012.

RESULTS

We included 33 patients with the JHTS, who were accounted for approximately 2.5% of the total number (1,342) of children seen at the emergency department with a mild head trauma. The prevalence of migraine in cases compared with controls did not differ. The proportion of patients with a first-degree relative with migraine was significantly higher in cases compared with controls (odds ratio, 2.69; 95% confidence interval, 1.16-6.22; p = 0.010).

CONCLUSION

The JHTS is a relatively rare phenomenon, seen in approximately 2.5% of all children seen at the emergency department with mild brain injury. This study demonstrates a significant relationship between the JHTS and a positive history of migraine in first-degree relatives.

Health-related quality of life after mild, moderate and severe traumatic brain injury: patterns and predictors of suboptimal functioning during the first year after injury

BACKGROUND

The Glasgow Outcome Scale Extended (GOSE) is the established functional outcome scale to assess disability following traumatic brain injury (TBI), however does not capture the patient's subjective perspective. Health-related quality of life (HRQL) does capture the individual's perception of disability after TBI, and has therefore been recognized as an important outcome in TBI. In contrast to GOSE, HRQL enables comparison of health outcome across various disease states and with healthy individuals. We aimed to assess functional outcome, HRQL, recovery, and predictors of 6 and 12-month outcome in a comprehensive sample of patients with mild, moderate or severe TBI, and to examine the relationship between functional impairment (GOSE) and HRQL.

METHODS

A prospective cohort study was conducted among a sample of 2066 adult TBI patients who attended the emergency department (ED). GOSE was determined through questionnaires or structured interviews. Questionnaires 6 and 12 months after ED treatment included socio-demographic information and HRQL measured with Short-Form Health Survey (SF-36; reflecting physical, mental and social functioning) and Perceived Quality of Life Scale (PQoL; measuring degree of satisfaction with functioning).

RESULTS

996 TBI survivors with mild, moderate or severe TBI completed the 6-month questionnaire. Functional outcome and HRQL after moderate or severe TBI was significantly lower than after mild TBI. Patients with moderate TBI showed greatest improvement. After one year, the mild TBI group reached outcomes comparable to population norms. TBI of all severities highly affected SF-36 domains physical and social functioning, and physical and emotional role functioning. GOSE scores were highly related to all SF-36 domains and PQoL scores. Female gender, older age, co-morbidity and high ISS were strongest independent predictors of decreased HRQL at 6 and 12 months after TBI.

CONCLUSIONS

HRQL and recovery patterns differ for mild, moderate and severe TBI. This study indicates that GOSE, although clinically relevant, fails to capture the subjective perspective of TBI patients, which endorses the use of HRQL as valuable addition to established instruments in assessing disability following TBI. Influence of TBI severity on recovery, together with female gender, older age, co-morbidity and high ISS should be considered in long-term follow-up and intervention programs.

Impact of depression and post-traumatic stress disorder on functional outcome and health-related quality of life of patients with mild traumatic brain injury

The impact of disability following traumatic brain injury (TBI), assessed by functional measurement scales for TBI or by health-related quality of life (HRQoL), may vary because of a number of factors, including presence of depression or post-traumatic stress disorder (PTSD). The aim of this study was to assess prevalence and impact of depression and PTSD on functional outcome and HRQoL six and 12 months following mild TBI. We selected a sample of 1919 TBI patients who presented to the emergency department (ED) followed by either hospital admission or discharge to the home environment. The sample received postal questionnaires six and 12 months after treatment at the ED. The questionnaires included items regarding socio-demographics, the 36-item Short-Form Health Survey (SF-36), the Perceived Quality of Life Scale (PQoL), the Beck Depression Inventory, and the Impact of Event Scale. A total of 797 (42%) TBI patients completed the six-month follow-up survey. Depression and PTSD prevalence rates at both the six- and 12-month follow-up were 7% and 9%, respectively. Living alone was an independent predictor of depression and/or PTSD at six- and 12-month follow-up. Depression and PTSD were associated with a significantly decreased functional outcome (measured with Glasgow Outcome Scale Extended) and HRQoL (measured using the SF-36 and the PQoL). We conclude that depression and/or PTSD are relatively common in our sample of TBI patients and associated with a considerable decrease in functional outcome and HRQoL.

The vegetative state/unresponsive wakefulness syndrome: a systematic review of prevalence studies

One of the worst outcomes of acquired brain injury is the vegetative state, recently renamed 'unresponsive wakefulness syndrome' (VS/UWS). A patient in VS/UWS shows reflexive behaviour such as spontaneous eye opening and breathing, but no signs of awareness of the self or the environment. We performed a systematic review of VS/UWS prevalence studies and assessed their reliability. Medline, Embase, the Cochrane Library, CINAHL and PsycINFO were searched in April 2013 for cross-sectional point or period prevalence studies explicitly stating the prevalence of VS/UWS due to acute causes within the general population. We additionally checked bibliographies and consulted experts in the field to obtain 'grey data' like government reports. Relevant publications underwent quality assessment and data-extraction. We retrieved 1032 papers out of which 14 met the inclusion criteria. Prevalence figures varied from 0.2 to 6.1 VS/UWS patients per 100 000 members of the population. However, the publications' methodological quality differed substantially, in particular with regards to inclusion criteria and diagnosis verification. The reliability of VS/UWS prevalence figures is poor. Methodological flaws in available prevalence studies, the fact that 5/14 of the studies predate the identification of the minimally conscious state (MCS) as a distinct entity in 2002, and insufficient verification of included cases may lead to both overestimation and underestimation of the actual number of patients in VS/UWS.

White matter changes in comatose survivors of anoxic ischemic encephalopathy and traumatic brain injury: comparative diffusion-tensor imaging study

PURPOSE

To analyze white matter pathologic abnormalities by using diffusion-tensor (DT) imaging in a multicenter prospective cohort of comatose patients following cardiac arrest or traumatic brain injury (TBI).

MATERIALS AND METHODS

Institutional review board approval and informed consent from proxies and control subjects were obtained. DT imaging was performed 5-57 days after insult in 49 cardiac arrest and 40 TBI patients. To control for DT imaging-processing variability, patients' values were normalized to those of 111 control subjects. Automated segmentation software calculated normalized axial diffusivity (λ1) and radial diffusivity (λ⊥) in 19 predefined white matter regions of interest (ROIs). DT imaging variables were compared by using general linear modeling, and side-to-side Pearson correlation coefficients were calculated. P values were corrected for multiple testing (Bonferroni).

RESULTS

In central white matter, λ1 differed from that in control subjects in six of seven TBI ROIs and five of seven cardiac arrest ROIs (all P < .01). The λ⊥ differed from that in control subjects in all ROIs in both patient groups (P < .01). In hemispheres, λ1 was decreased compared with that in control subjects in three of 12 TBI ROIs (P < .05) and nine of 12 cardiac arrest ROIs (P < .01). The λ⊥ was increased in all TBI ROIs (P < .01) and in seven of 12 cardiac arrest ROIs (P < .05). Cerebral hemisphere λ1 was lower in cardiac arrest than in TBI in six of 12 ROIs (P < .01), while λ⊥ was higher in TBI than in cardiac arrest in eight of 12 ROIs (P < .01). Diffusivity values were symmetrically distributed in cardiac arrest (P < .001 for side-to-side correlation) but not in TBI patients.

CONCLUSION

DT imaging findings are consistent with the known predominance of cerebral hemisphere axonal injury in cardiac arrest and chiefly central myelin injury in TBI. This consistency supports the validity of DT imaging for differentiating axon and myelin damage in vivo in humans.

Physician-based emergency medical service deployment characteristics in severe traumatic brain injury: a Dutch multicenter study

INTRODUCTION

Prehospital guidelines advise advanced life support in all patients with severe traumatic brain injury (TBI). In the Netherlands, it is recommended that prehospital advanced life support is particularly provided by a physician-based helicopter emergency medical service (P-HEMS) in addition to paramedic care (EMS). Previous studies have however shown that a substantial part of severe TBI patients is exclusively treated by an EMS team. In order to better understand this phenomenon, we evaluated P-HEMS deployment characteristics in severe TBI in a multicenter setting.

METHODS

The database included patient demographics, prehospital and injury severity parameters and determinants of EMS or EMS/P-HEMS dispatch in 334 patients with severe TBI admitted to level 1 trauma centres in the Netherlands.

RESULTS

P-HEMS was deployed in 62% of patients with severe TBI. Patients treated by the P-HEMS had a higher injury severity score (29 (20-38)) vs. (25 (16-30); P<0.001), more frequently required blood product transfusions (41% vs. 29%; P=0.03) and recurrently suffered from TBI with extracranial injuries (33% vs. 6%; P<0.001) than patients solely treated by an EMS. The prehospital endotracheal intubation rate was higher in the P-HEMS group in isolated TBI (93% vs. 19%; P<0.001) or TBI with extracranial injuries (96% vs. 43%; P<0.001) compared to the EMS group. In the EMS group, more patients were secondary referred to a level 1 trauma centre (32% vs. 4%; P<0.001 vs. P-HEMS). Despite higher injury severity levels in P-HEMS patients, 6-month mortality rates were similar among groups, irrespective of the presence of extracranial injuries in addition to TBI. Deployment of P-HEMS estimated 52% and 72% (P<0.001) in urban and rural regions, respectively, with comparable endotracheal intubation rates among regions.

CONCLUSIONS

This study shows that a physician-based HEMS was more frequently deployed in patients with severe TBI in the presence of extracranial injuries, and in rural trauma regions. Treatment of severe TBI patients by a paramedic EMS only was associated with a higher incidence of secondary referrals to a level I trauma centre. Our data support adjustment of local prehospital guidelines for patients with severe TBI to the geographical context.

Association between thyroid function, thyroid autoimmunity, and state and trait factors of depression

OBJECTIVE

The aim of this study was to investigate whether thyroid function and thyroid peroxidase antibodies (TPOAb) are associated with depression, when using both state and trait parameters of depression.

METHOD

In 1125 participants of the Nijmegen Biomedical Study, thyroid-stimulating hormone (TSH), free thyroxine (FT4), and TPOAb were measured twice. The Beck Depression Inventory (BDI), a self-reported lifetime diagnosis of depression, and the neuroticism scale of the Eysenck Personality Questionnaire Revised Short Scale (EPQ-RSS) were used to evaluate the presence of state and trait features of depression.

RESULTS

We found no association between TSH and FT4 levels and BDI score, current depression, lifetime diagnosis of depression, and EPQ-RSS neuroticism score. Subjects with TPOAb had higher EPQ-RSS neuroticism scores in comparison with subjects without TPOAb, mean score 4.1 vs. 3.2 (regression coefficient 0.70; 95% CI 0.1-1.3; P-value 0.02 after adjustment for confounders). The prevalence of a lifetime diagnosis of depression was higher in subjects with positive TPOAb in comparison with participants without TPOAb: 24.2% vs. 16.7% (relative risk 1.4; 95% CI 1.0-2.1; P-value 0.04 after adjustment for confounders).

CONCLUSION

Thyroid peroxidase antibodies are positively associated with trait markers of depression. The presence of TPOAb may be a vulnerability marker for depression.

Genome-wide association uncovers shared genetic effects among personality traits and mood states

Measures of personality and psychological distress are correlated and exhibit genetic covariance. We conducted univariate genome-wide SNP (~2.5 million) and gene-based association analyses of these traits and examined the overlap in results across traits, including a prediction analysis of mood states using genetic polygenic scores for personality. Measures of neuroticism, extraversion, and symptoms of anxiety, depression, and general psychological distress were collected in eight European cohorts (n ranged 546-1,338; maximum total n = 6,268) whose mean age ranged from 55 to 79 years. Meta-analysis of the cohort results was performed, with follow-up associations of the top SNPs and genes investigated in independent cohorts (n = 527-6,032). Suggestive association (P = 8 × 10(-8)) of rs1079196 in the FHIT gene was observed with symptoms of anxiety. Other notable associations (P < 6.09 × 10(-6)) included SNPs in five genes for neuroticism (LCE3C, POLR3A, LMAN1L, ULK3, SCAMP2), KIAA0802 for extraversion, and NOS1 for general psychological distress. An association between symptoms of depression and rs7582472 (near to MGAT5 and NCKAP5) was replicated in two independent samples, but other replication findings were less consistent. Gene-based tests identified a significant locus on chromosome 15 (spanning five genes) associated with neuroticism which replicated (P < 0.05) in an independent cohort. Support for common genetic effects among personality and mood (particularly neuroticism and depressive symptoms) was found in terms of SNP association overlap and polygenic score prediction. The variance explained by individual SNPs was very small (up to 1%) confirming that there are no moderate/large effects of common SNPs on personality and related traits.

Development and external validation of a new PTA assessment scale

Background

Post-traumatic amnesia (PTA) is a key symptom of traumatic brain injury (TBI). Accurate assessment of PTA is imperative in guiding clinical decision making. Our aim was to develop and externally validate a short, examiner independent and practical PTA scale, by selecting the most discriminative items from existing scales and using a three-word memory test.

Methods

Mild, moderate and severe TBI patients and control subjects were assessed in two separate cohorts, one for derivation and one for validation, using a questionnaire comprised of items from existing PTA scales. We tested which individual items best discriminated between TBI patients and controls, represented by sensitivity and specificity. We then created our PTA scale based on these results. This new scale was externally evaluated for its discriminative value using Receiver Operating Characteristic (ROC) analysis and compared to existing PTA scales.

Results

The derivation cohort included 126 TBI patients and 31 control subjects; the validation cohort consisted of 132 patients and 30 controls. A set of seven items was eventually selected to comprise the new PTA scale: age, name of hospital, time, day of week, month, mode of transport and recall of three words. This scale demonstrated adequate discriminative values compared to existing PTA scales on three consecutive administrations in the validation cohort.

Conclusion

We introduce a valid, practical and examiner independent PTA scale, which is suitable for mild TBI patients at the emergency department and yet still valuable for the follow-up of more severely injured TBI patients.

Mild traumatic brain injury

Traumatic Brain Injury (TBI) is among the most frequent neurological disorders. Of all TBIs 90% are considered mild with an annual incidence of 100–300/100.000. Intracranial complications of Mild Traumatic Brain Injury (MTBI) are infrequent (10%), requiring neurosurgical intervention in a minority of cases (1%), but potentially life-threatening (case fatality rate 0,1%). Hence, a true health management problem exists because of the need to exclude the small chance of a life threatening complication in large numbers of individual patients. The 2002 EFNS guidelines used a best evidence approach based on the literature until 2001 to guide initial management with respect to indications for CT, hospital admission, observation and follow up of MTBI patients. This updated EFNS guideline version for initial management inMTBI proposes a more selectively strategy for CT when major (dangerous mechanism, GCS<15, 2 points deterioration on the GCS, clinical signs of (basal) skull fracture, vomiting, anticoagulation therapy, post traumatic seizure) or minor (age, loss of consciousness, persistent anterograde amnesia, focal deficit, skull contusion, deterioration on the GCS) risk factors are present based on published decision rules with a high level of evidence. In addition clinical decision rules for CT now exist for children as well. Since 2001 recommendations, although with a lower level of evidence, have been published for clinical in hospital observation to prevent and treat other potential threads to the patient including behavioral disturbances (amnesia, confusion and agitation) and infection.

The reliability of magnetic resonance imaging in traumatic brain injury lesion detection

OBJECTIVE

This study compares inter-rater-reliability, lesion detection and clinical relevance of T2-weighted imaging (T2WI), Fluid Attenuated Inversion Recovery (FLAIR), T2*-gradient recalled echo (T2*-GRE) and Susceptibility Weighted Imaging (SWI) in Traumatic Brain Injury (TBI).

METHODS

Three raters retrospectively scored 56 TBI patients' MR images (12-76 years old, median TBI-MRI interval 7 weeks) on number, volume, location and intensity. Punctate lesions (diameter <10 mm) were scored separately from large lesions (diameter ≥ 10 mm). Injury severity was assessed with the Glasgow Coma Scale (GCS), outcome with the Glasgow Outcome Scale-Extended (GOSE).

RESULTS

Inter-rater-reliability for lesion volume and punctate lesion count was good (ICC = 0.69-0.94) except for punctate lesion count on T2WI (ICC = 0.19) and FLAIR (ICC = 0.15). SWI showed the highest number of lesions (mean = 30.0), followed by T2*-GRE (mean = 15.4), FLAIR (mean = 3.1) and T2WI (mean = 2.2). Sequences did not differ in detected lesion volume. Punctate lesion count on T2*-GRE (r = -0.53) and SWI (r = -0.49) correlated with the GCS (p < 0.001).

CONCLUSIONS

T2*-GRE and SWI are more sensitive than T2WI and FLAIR in detecting (haemorrhagic) traumatic punctate lesions. The correlation between number of punctate lesions on T2*-GRE/SWI and the GCS indicates that haemorrhagic lesions are clinically relevant. The considerable inter-rater-disagreement in this study advocates cautiousness in interpretation of punctate lesions using T2WI and FLAIR.

Multicenter evaluation of the course of coagulopathy in patients with isolated traumatic brain injury: relation to CT characteristics and outcome

This prospective multicenter study investigated the association of the course of coagulation abnormalities with initial computed tomography (CT) characteristics and outcome in patients with isolated traumatic brain injury (TBI). Patient demographics, coagulation parameters, CT characteristics, and outcome data of moderate and severe TBI patients without major extracranial injuries were prospectively collected. Coagulopathy was defined as absent, early but temporary, delayed, or early and sustained. Delayed/sustained coagulopathy was associated with a higher incidence of disturbed pupillary responses (40% versus 27%; p<0.001) and higher Traumatic Coma Data Bank (TCDB) CT classification (5 (2-5) versus 2 (1-5); p=0.003) than in patients without or with early, but short-lasting coagulopathy. The initial CT of patients with delayed/sustained coagulopathy more frequently showed intracranial hemorrhage and signs of raised intracranial pressure (ICP) compared to patients with early coagulopathy only. This was paralleled by higher in-hospital mortality rates (51% versus 33%; p<0.05), and poorer 6-month functional outcome in patients with delayed/sustained coagulopathy. The relative risk for in-hospital mortality was particularly related to disturbed pupillary responses (OR 8.19; 95% CI 3.15,21.32; p<0.001), early, short-lasting coagulopathy (OR 6.70; 95% CI 1.74,25.78; p=0.006), or delayed/sustained coagulopathy (OR 5.25; 95% CI 2.06,13.40; p=0.001). Delayed/sustained coagulopathy is more frequently associated with CT abnormalities and unfavorable outcome at 6 months after TBI than early, short-lasting coagulopathy. Our finding that not only the mere presence but also the time course of coagulopathy holds predictive value for patient outcome underlines the importance of systematic hemostatic monitoring over time in TBI.

Epidemiology, severity classification, and outcome of moderate and severe traumatic brain injury: a prospective multicenter study

Changes in the demographics, approach, and treatment of traumatic brain injury (TBI) patients require regular evaluation of epidemiological profiles, injury severity classification, and outcomes. This prospective multicenter study provides detailed information on TBI-related variables of 508 moderate-to-severe TBI patients. Variability in epidemiology and outcome is examined by comparing our cohort with previous multicenter studies. Additionally, the relation between outcome and injury severity classification assessed at different time points is studied. Based on the emergency department Glasgow Coma Scale (GCS), 339 patients were classified as having severe and 129 as having moderate TBI. In 15%, the diagnosis differed when the accident scene GCS was used for classification. In-hospital mortality was higher if severe TBI was diagnosed at both time points (44%) compared to moderate TBI at one or both time points (7-15%, p<0.001). Furthermore, 14% changed diagnosis when a threshold (≥6 h) for impaired consciousness was used as a criterion for severe TBI: In-hospital mortality was<5% when impaired consciousness lasted for<6 h. This suggests that combining multiple clinical assessments and using a threshold for impaired consciousness may improve the classification of injury severity and prediction of outcome. Compared to earlier multicenter studies, our cohort demonstrates a different case mix that includes a higher age (mean=47.3 years), more diffuse (Traumatic Coma Databank [TCDB] I-II) injuries (58%), and more major extracranial injuries (40%), with relatively high 6 month mortality rates for both severe (46%) and moderate (21%) TBI. Our results confirm that TBI epidemiology and injury patterns have changed in recent years whereas case fatality rates remain high.

Biomarkers of focal and diffuse traumatic brain injury

Traumatic brain injury (TBI) is a pathologically heterogeneous disease affecting people of all ages. The highest incidence of TBI occurs in young people and the average age is 30 to 40 years. Injury grading may range from mild with a low frequency (1 per 100) of life-threatening intracranial hematoma that needs immediate neurosurgical operation and very low mortality (1 per 1,000) to severe with a high likelihood of life-threatening intracranial hematoma (up to 1 per 3), a 40% case fatality rate and a high disability rate (2 per 3) in survivors. Estimation of the prognosis in severe TBI is currently based on demographic and clinical predictors, including age, Glasgow Coma Scale, pupillary reactions, extracranial injury (hypotension and hypoxia) and computed tomography indices (brain swelling, focal mass lesions, subarachnoid hemorrhage). Biomarkers reflecting damage to neurons and astrocytes may add important complementary information to clinical predictors of outcome and provide insight into the pathophysiology of TBI.

Clinical characteristics and pathophysiological mechanisms of focal and diffuse traumatic brain injury

Traumatic brain injury (TBI) is a frequent and clinically highly heterogeneous neurological disorder with large socioeconomic consequences. TBI severity classification, based on the hospital admission Glasgow Coma Scale (GCS) score, ranges from mild (GCS 13-15) and moderate (GCS 9-12) to severe (GCS ≤ 8). The GCS reflects the risk of dying from TBI, which is low after mild (∼1%), intermediate after moderate (up to 15%) and high (up to 40%) after severe TBI. Intracranial damage can be focal, such as epidural and subdural haematomas and parenchymal contusions, or diffuse, for example traumatic axonal injury and diffuse cerebral oedema, although this distinction is somewhat arbitrary. Study of the cellular and molecular post-traumatic processes is essential for the understanding of TBI pathophysiology but even more to find therapeutic targets for the development of neuroprotective drugs to be eventually used in human beings. To date, studies in vitro and in vivo, mainly in animals but also in human beings, are unravelling the pathological TBI mechanisms at high pace. Nevertheless, TBI pathophysiology is all but completely elucidated. Neuroprotective treatment studies in human beings have been disappointing thus far and have not resulted in commonly accepted drugs. This review presents an overview on the clinical aspects and the pathophysiology of focal and diffuse TBI, and it highlights several acknowledged important events that occur on molecular and cellular level after TBI.

GFAP and S100B are biomarkers of traumatic brain injury: an observational cohort study

BACKGROUND

Biomarker levels in blood after traumatic brain injury (TBI) may offer diagnostic and prognostic tools in addition to clinical indices. This study aims to validate glial fibrillary acidic protein (GFAP) and S100B concentrations in blood as outcome predictors of TBI using cutoff levels of 1.5 μg/L for GFAP and 1.13 μg/L for S100B from a previous study.

METHODS

In 79 patients with TBI (Glasgow Coma Scale score [GCS] ≤12), serum, taken at hospital admission, was analyzed for GFAP and S100B. Data collected included injury mechanism, age, gender, mass lesion on CT, GCS, pupillary reactions, Injury Severity Score (ISS), presence of hypoxia, and hypotension. Outcome was assessed, using the Glasgow Outcome Scale Extended (dichotomized in death vs alive and unfavorable vs favorable), 6 months post injury.

RESULTS

In patients who died compared to alive patients, median serum levels were increased: GFAP 33.4-fold and S100B 2.1-fold. In unfavorable compared to favorable outcome, GFAP was increased 19.8-fold and S100B 2.1-fold. Univariate logistic regression analysis revealed that mass lesion, GFAP, absent pupils, age, and ISS, but not GCS, hypotension, or hypoxia, predicted death and unfavorable outcome. Multivariable analysis showed that models containing mass lesion, pupils, GFAP, and S100B were the strongest in predicting death and unfavorable outcome. S100B was the strongest single predictor of unfavorable outcome with 100% discrimination.

CONCLUSION

This study confirms that GFAP and S100B levels in serum are adjuncts to the assessment of brain damage after TBI and may enhance prognostication when combined with clinical variables.

Outcome prediction in mild traumatic brain injury: age and clinical variables are stronger predictors than CT abnormalities

Mild traumatic brain injury (mTBI) is a common heterogeneous neurological disorder with a wide range of possible clinical outcomes. Accurate prediction of outcome is desirable for optimal treatment. This study aimed both to identify the demographic, clinical, and computed tomographic (CT) characteristics associated with unfavorable outcome at 6 months after mTBI, and to design a prediction model for application in daily practice. All consecutive mTBI patients (Glasgow Coma Scale [GCS] score: 13-15) admitted to our hospital who were age 16 or older were included during an 8-year period as part of the prospective Radboud University Brain Injury Cohort Study (RUBICS). Outcome was assessed at 6 months post-trauma using the Glasgow Outcome Scale-Extended (GOSE), dichotomized into unfavorable (GOSE score 1-6) and favorable (GOSE score 7-8) outcome groups. The predictive value of several variables was determined using multivariate binary logistic regression analysis. We included 2784 mTBI patients and found CT abnormalities in 20.7% of the 1999 patients that underwent a head CT. Age, extracranial injuries, and day-of-injury alcohol intoxication proved to be the strongest outcome predictors. The presence of facial fractures and the number of hemorrhagic contusions emerged as CT predictors. Furthermore, we showed that the predictive value of a scheme based on a modified Injury Severity Score (ISS), alcohol intoxication, and age equalled the value of one that also included CT characteristics. In fact, it exceeded one that was based on CT characteristics alone. We conclude that, although valuable for the identification of the individual mTBI patient at risk for deterioration and eventual neurosurgical intervention, CT characteristics are imperfect predictors of outcome after mTBI.

Should anterior pituitary function be tested during follow-up of all patients presenting at the emergency department because of traumatic brain injury?

CONTEXT

A wide range (15-56%) of prevalences of anterior pituitary insufficiency are reported in patients after traumatic brain injury (TBI). However, different study populations, study designs, and diagnostic procedures were used. No data are available on emergency-department-based cohorts of TBI patients.

OBJECTIVE

To assess the prevalence of pituitary dysfunction in an emergency-department-based cohort of TBI patients using strict endocrinological diagnostic criteria.

METHODS

Of all the patients presenting in the emergency department with TBI over a 2-year period, 516 matched the inclusion criteria. One hundred and seven patients (77 with mild TBI and 30 with moderate/severe TBI) agreed to participate. They were screened for anterior pituitary insufficiency by GHRH-arginine testing, evaluation of fasting morning hormone levels (cortisol, TSH, free thyroxine, FSH, LH, and 17beta-estradiol or testosterone), and menstrual history 3-30 months after TBI. Abnormal screening results were defined as low peak GH to GHRH-arginine, or low levels of any of the end-organ hormones with low or normal pituitary hormone levels. Patients with abnormal screening results were extensively evaluated, including additional hormone provocation tests (insulin tolerance test, ACTH stimulation test, and repeated GHRH-arginine test) and assessment of free testosterone levels.

RESULTS

Screening results were abnormal in 15 of 107 patients. In a subsequent extensive endocrine evaluation, anterior pituitary dysfunction was diagnosed in only one patient (partial hypocortisolism).

CONCLUSION

By applying strict diagnostic criteria to an emergency-department-based cohort of TBI patients, it was shown that anterior pituitary dysfunction is rare (<1%). Routine pituitary screening in unselected patients after TBI is unlikely to be cost-effective.

Cognitive performance after Mild Traumatic Brain Injury: The impact of poor effort on test results and its relation to distress, personality and litigation

PRIMARY OBJECTIVE

To compare consecutive Mild Traumatic Brain Injury (MTBI) patients with and without adequate effort on cognitive performance, litigation status, fatigue, distress and personality.

RESEARCH DESIGN

(Neuro)psychological assessment was done 6 months post-injury in 110 patients from a cohort of 618 consecutive MTBI patients aged 18-60, who attended the emergency department of our level I trauma centre. Effort was tested with the Amsterdam Short Term Memory test.

MAIN OUTCOME AND RESULTS

Thirty patients (27%) failed the effort test. Poor effort was associated with significantly poorer scores on seven out of eleven measures, covering all tested domains. Poor effort was associated with lower educational level and changes in work status, but not litigation. Furthermore, poor effort was related to high levels of distress, Type-D personality and fatigue.

CONCLUSIONS

Even in a sample of non-referred MTBI patients, poor effort was common and was strongly associated with inferior test performance. These findings imply that effort testing should be part of all cognitive assessments, also outside mediolegal settings. Behavioural factors like distress and personality should be considered as potential threats to the validity of neuropsychological testing after MTBI.

Biomarkers in spinal cord injury

STUDY DESIGN

Literature review.

OBJECTIVES

In traumatic spinal cord injury (SCI), much effort has been put into the evaluation of SCI severity and the prediction of recovery potential. An accurate prediction of the initial damage of the spinal cord that differentiates between the severities of SCI however, may help physicians in choosing a particular neuroprotective treatment in the acute phase. Neurochemical biomarkers may possibly fulfil these requirements. The aim of this review was to describe (1) the current status of neurochemical biomarkers in SCI; (2) their potential diagnostic role in SCI.

METHODS

MEDLINE was searched from 1966 to 2008 to identify publications concerning biomarkers in traumatic SCI.

RESULTS

The biomarkers S-100beta, neuron-specific enolase, neurofilament light chain, and Glial fibrillary acidic protein are significantly increased in cases of (experimental) spinal cord injury. Furthermore, increased serum concentrations of S-100beta have been correlated with an unfavourable functional outcome. Although biomarkers in SCI show promising results, considerations and shortcomings, such as polytrauma, haemolysis, extracerebral sources, and poor resuscitation, must be studied in greater detail before biomarkers can be utilised in the clinical care of SCI.

CONCLUSIONS

Quantitative standards for determining the extent of SCI during the acute phase must be developed and validated. Even though increased concentrations of neurochemical biomarkers have been identified in patients with SCI, these do not yet provide a sensitive prognostic tool. Considering the limited availability of sensitive prognostic tools, neurochemical biomarkers of SCI should be evaluated and validated in future clinical trials.

Early prediction of favourable recovery 6 months after mild traumatic brain injury

BACKGROUND

Predicting outcome after mild traumatic brain injury (MTBI) is notoriously difficult. Although it is recognised that milder head injuries do not necessarily mean better outcomes, less is known about the factors that do enable early identification of patients who are likely to recover well.

OBJECTIVE

To develop and internally validate two prediction rules for identifying patients who have the highest chance for good 6 month recovery.

METHODS

A prospective cohort study was conducted among patients with MTBI admitted to the emergency department. Apart from MTBI severity indices, a range of pre-, peri- and early post-injury variables were considered as potential predictors, including emotional and physical functioning. Logistic regression modelling was used to predict the absence of postconcussional symptoms (PCS) and full return to work (RTW).

RESULTS

At follow-up, 64% of the 201 participating patients reported full recovery. Based on our prediction rules, patients without premorbid physical problems, low levels of PCS and post-traumatic stress early after injury had a 90% chance of remaining free of PCS. Patients with over 11 years of education, without nausea or vomiting on admission, with no additional extracranial injuries and only low levels of pain early after injury had a 90% chance of full RTW. The discriminative ability of the prediction models was satisfactory, with an area under the curve >0.70 after correction for optimism.

CONCLUSIONS

Early identification of patients with MTBI who are likely to have good 6 month recovery was feasible on the basis of relatively simple prognostic models. A score chart was derived from the models to facilitate clinical application.

Outcome after complicated minor head injury

BACKGROUND AND PURPOSE

Functional outcome in patients with minor head injury with neurocranial traumatic findings on CT is largely unknown. We hypothesized that certain CT findings may be predictive of poor functional outcome.

MATERIALS AND METHODS

All patients from the CT in Head Injury Patients (CHIP) study with neurocranial traumatic CT findings were included. The CHIP study is a prospective, multicenter study of consecutive patients, > or =16 years of age, presenting within 24 hours of blunt head injury, with a Glasgow Coma Scale (GCS) score of 13-14 or a GCS score of 15 and a risk factor. Primary outcome was functional outcome according to the Glasgow Outcome Scale (GOS). Other outcome measures were the modified Rankin Scale (mRS), the Barthel Index (BI), and number and severity of postconcussive symptoms. The association between CT findings and outcome was assessed by using univariable and multivariable regression analysis.

RESULTS

GOS was assessed in 237/312 patients (76%) at an average of 15 months after injury. There was full recovery in 150 patients (63%), moderate disability in 70 (30%), severe disability in 7 (3.0%), and death in 10 (4.2%). Outcome according to the mRS and BI was also favorable in most patients, but 82% of patients had postconcussive symptoms. Evidence of parenchymal damage was the only independent predictor of poor functional outcome (odds ratio = 1.89, P = .022).

CONCLUSION

Patients with neurocranial complications after minor head injury generally make a good functional recovery, but postconcussive symptoms may persist. Evidence of parenchymal damage on CT was predictive of poor functional outcome.

A history of loss of consciousness or post-traumatic amnesia in minor head injury: "conditio sine qua non" or one of the risk factors?

OBJECTIVE

A history of loss of consciousness (LOC) or post-traumatic amnesia (PTA) is commonly considered a prerequisite for minor head injury (MHI), although neurocranial complications also occur when LOC/PTA are absent, particularly in the presence of other risk factors. The purpose of this study was to evaluate whether known risk factors for complications after MHI in the absence of LOC/PTA have the same predictive value as when LOC/PTA are present.

METHODS

A prospective multicentre study was performed in four university hospitals between February 2002 and August 2004 of consecutive blunt head injury patients (> or = 16 years) presenting with a normal level of consciousness and a risk factor. Outcome measures were any neurocranial traumatic CT finding and neurosurgical intervention. Common odds ratios (OR) were estimated for each of the risk factors and tested for homogeneity.

RESULTS

2462 patients were included: 1708 with and 754 without LOC/PTA. Neurocranial traumatic findings on CT were present in 7.5% and were more common when LOC/PTA was present (8.7%). Neurosurgical intervention was required in 0.4%, irrespective of the presence of LOC/PTA. ORs were comparable across the two subgroups (p>0.05), except for clinical evidence of a skull fracture, with high ORs both when LOC/PTA was present (OR = 37, 95% CI 17 to 80) or absent (OR = 6.9, 95% CI 1.8 to 27). LOC and PTA had significant ORs of 1.9 (95% CI 1.0 to 2.7) and 1.7 (95% CI 1.3 to 2.3), respectively.

CONCLUSION

Known risk factors have comparable ORs in MHI patients with or without LOC or PTA. MHI patients without LOC or PTA need to be explicitly considered in clinical guidelines.

Cognitive complaints after mild traumatic brain injury: things are not always what they seem

OBJECTIVE

To compare nonreferred, emergency department (ED)-admitted mild traumatic brain injury (MTBI) patients with and without self-reported cognitive complaints on (1) demographic variables and injury characteristics; (2) neuropsychological test performance; (3) 12-day self-monitoring of perceived cognitive problems; and (4) emotional distress, physical functioning, and personality.

METHODS

(Neuro)psychological assessment was carried out 6 months post-injury in 79 patients out of a cohort of 618 consecutive MTBI patients aged 18-60, who attended the ED of our level I trauma centre. Cognitive complaints were assessed with the Rivermead Postconcussional Symptoms Questionnaire (RPSQ). In addition, patients monitored concentration problems and forgetfulness during 12 consecutive days.

RESULTS

Self-reported cognitive complaints were reported by 39% of the patients. These complaints were strongly related to lower educational levels, emotional distress, personality, and poorer physical functioning (especially fatigue) but not to injury characteristics. Severity of self-reported cognitive complaints was neither associated with the patients' daily observations of cognitive problems nor with outcome on a range of neuropsychological tests.

CONCLUSION

Self-reported cognitive complaints were more strongly related to premorbid traits and physical and emotional state factors than to actual cognitive impairments. In line with previous work, this suggests that treatment of emotional distress and fatigue may also reduce cognitive complaints. Cognitive outcome assessment of symptomatic MTBI patients should not be restricted to checklist ratings only, but also include a (neuro)psychological screening. In addition, daily monitoring of complaints is a useful method to gather information about the frequency and pattern of cognitive problems in daily life.

Minor head injury: guidelines for the use of CT--a multicenter validation study

PURPOSE

To prospectively and externally validate published national and international guidelines for the indications of computed tomography (CT) in patients with a minor head injury.

MATERIALS AND METHODS

The study protocol was institutional review board approved. All patients implicitly consented to use of their deidentified data for research purposes. Between February 2002 and August 2004, data were collected in consecutive adult patients with blunt minor head injury (Glasgow Coma Scale score of 13-14 or 15) and a risk factor for neurocranial traumatic complications at presentation at four Dutch university hospitals. Primary outcome was any neurocranial traumatic CT finding. Secondary outcomes were clinically relevant traumatic CT findings and neurosurgical intervention. Sensitivity and specificity of each guideline for all outcomes and the number of patients needed to scan to detect one outcome (ie, the number of patients needed to undergo CT to find one patient with a neurocranial traumatic CT finding, a clinically relevant traumatic CT finding, or a CT finding that required neurosurgical intervention) were estimated.

RESULTS

Data were available for 3181 patients. Only the European Federation of Neurological Societies guidelines reached a sensitivity of 100% for all outcomes. Specificity was 0.0%-0.5%. The Dutch guidelines had the lowest sensitivity (76.5%) for neurosurgical interventions. The best specificities for traumatic CT findings and neurosurgical interventions were reached with the criteria proposed by the United Kingdom National Institute for Clinical Excellence (NICE) (46.1% and 43.6%, respectively), albeit at relatively low sensitivities (82.1% and 94.1%, respectively). The number of patients needed to scan ranged from six to 13 for traumatic CT findings and from 79 to 193 for neurosurgical interventions.

CONCLUSION

All validated guidelines demonstrated a trade-off between sensitivity and specificity. The lowest number of patients needed to scan for either of the outcomes was reached with the NICE criteria.

SUPPLEMENTAL MATERIAL

radiology.rsnajnls.org/cgi/content/full/2452061509/DC1 (c) RSNA, 2007.

Predicting intracranial traumatic findings on computed tomography in patients with minor head injury: the CHIP prediction rule

BACKGROUND

Prediction rules for patients with minor head injury suggest that the use of computed tomography (CT) may be limited to certain patients at risk for intracranial complications. These rules apply only to patients with a history of loss of consciousness, which is frequently absent.

OBJECTIVE

To develop a prediction rule for the use of CT in patients with minor head injury, regardless of the presence or absence of a history of loss of consciousness.

DESIGN

Prospective, observational study.

SETTING

4 university hospitals in the Netherlands that participated in the CT in Head Injury Patients (CHIP) study.

PATIENTS

Consecutive adult patients with minor head injury (> or =16 years of age) with a Glasgow Coma Scale (GCS) score of 13 to 14 or with a GCS score of 15 and at least 1 risk factor.

MEASUREMENTS

Outcomes were any intracranial traumatic CT finding and neurosurgical intervention. The authors performed logistic regression analysis by using variables from existing prediction rules and guidelines, with internal validation by using bootstrapping.

RESULTS

3181 patients were included (February 2002 to August 2004): 243 (7.6%) had intracranial traumatic CT findings and 17 (0.5%) underwent neurosurgical intervention. A detailed prediction rule was developed from which a simple rule was derived. Sensitivity of both rules was 100% for neurosurgical interventions, with an associated specificity of 23% to 30%. For intracranial traumatic CT findings, sensitivity and specificity were 94% to 96% and 25% to 32%, respectively. Potential CT reduction by implementing the prediction rule was 23% to 30%. Internal validation showed slight optimism for the model's performance.

LIMITATION

External validation of the prediction model will be required.

CONCLUSION

The authors propose the highly sensitive CHIP prediction rule for the selective use of CT in patients with minor head injury with or without loss of consciousness.