Is Diffuse Axonal Injury Different in Adults and Children? An Analysis of National Trauma Database.

BACKGROUND: Diffuse axonal injury (DAI) is typically associated with significant mechanisms of injury and the effects of acceleration-deceleration forces on brain tissues. The prognosis of DAI remains a matter of active investigation, but little is known about outcome differences between adult and pediatric populations with DAI. METHODS: We performed a retrospective cohort study involving blunt trauma patients with DAI between the years 1997 and 2018 from the Israeli National Trauma Registry. The patients were divided to pediatric (age <15 years) and adult (age >15 years) groups, with subsequent comparison of demographics and outcomes. RESULTS: Diffuse axonal injury was identified in 1983 patients, including 469 pediatric victims (23.6%) and 1514 adults (76.4%). Adults had higher Injury Severity Score (20.5% vs 13.2%, P = 0.0004), increased mortality (17.7% vs 13.4%, P < 0.0001), longer hospitalizations (58.4% vs 44.4%, P < 0.001), and higher rehabilitation need rates (56.4% vs 41.8%, P < 0.0001). Associated extracranial injuries were also more common in adults, particularly to the chest. CONCLUSIONS: Pediatric patients with DAI have improved outcomes and fewer associated injuries than adult counterparts.

Magnetic Resonance Imaging Findings Are Associated with Long-Term Global Neurological Function or Death after Traumatic Brain Injury in Critically Ill Children.

The identification of children with traumatic brain injury (TBI) who are at risk of death or poor global neurological functional outcome remains a challenge. Magnetic resonance imaging (MRI) can detect several brain pathologies that are a result of TBI; however, the types and locations of pathology that are the most predictive remain to be determined. Forty-two critically ill children with TBI were recruited prospectively from pediatric intensive care units at five Canadian children's hospitals. Pathologies detected on subacute phase MRIs included cerebral hematoma, herniation, cerebral laceration, cerebral edema, midline shift, and the presence and location of cerebral contusion or diffuse axonal injury (DAI) in 28 regions of interest were assessed. Global functional outcome or death more than 12 months post-injury was assessed using the Pediatric Cerebral Performance Category score. Linear modeling was employed to evaluate the utility of an MRI composite score for predicting long-term global neurological function or death after injury, and nonlinear Random Forest modeling was used to identify which MRI features have the most predictive utility. A linear predictive model of favorable versus unfavorable long-term outcomes was significantly improved when an MRI composite score was added to clinical variables. Nonlinear Random Forest modeling identified five MRI variables as stable predictors of poor outcomes: presence of herniation, DAI in the parietal lobe, DAI in the subcortical white matter, DAI in the posterior corpus callosum, and cerebral contusion in the anterior temporal lobe. Clinical MRI has prognostic value to identify children with TBI at risk of long-term unfavorable outcomes.

Time course and diagnostic utility of NfL, tau, GFAP, and UCH-L1 in subacute and chronic TBI.

OBJECTIVE: To determine whether neurofilament light (NfL), glial fibrillary acidic protein (GFAP), tau, and ubiquitin C-terminal hydrolase-L1 (UCH-L1) measured in serum relate to traumatic brain injury (TBI) diagnosis, injury severity, brain volume, and diffusion tensor imaging (DTI) measures of traumatic axonal injury (TAI) in patients with TBI. METHODS: Patients with TBI (n = 162) and controls (n = 68) were prospectively enrolled between 2011 and 2019. Patients with TBI also underwent serum, functional outcome, and imaging assessments at 30 (n = 30), 90 (n = 48), and 180 (n = 59) days, and 1 (n = 84), 2 (n = 57), 3 (n = 46), 4 (n = 38), and 5 (n = 29) years after injury. RESULTS: At enrollment, patients with TBI had increased serum NfL compared to controls (p < 0.0001). Serum NfL decreased over the course of 5 years but remained significantly elevated compared to controls. Serum NfL at 30 days distinguished patients with mild, moderate, and severe TBI from controls with an area under the receiver-operating characteristic curve (AUROC) of 0.84, 0.92, and 0.92, respectively. At enrollment, serum GFAP was elevated in patients with TBI compared to controls (p < 0.001). GFAP showed a biphasic release in serum, with levels decreasing during the first 6 months of injury but increasing over the subsequent study visits. The highest AUROC for GFAP was measured at 30 days, distinguishing patients with moderate and severe TBI from controls (both 0.89). Serum tau and UCH-L1 showed weak associations with TBI severity and neuroimaging measures. Longitudinally, serum NfL was the only biomarker that was associated with the likely rate of MRI brain atrophy and DTI measures of progression of TAI. CONCLUSIONS: Serum NfL shows greater diagnostic and prognostic utility than GFAP, tau, and UCH-L1 for subacute and chronic TBI. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that serum NfL distinguishes patients with mild TBI from healthy controls.

Neurofilament light as a biomarker in traumatic brain injury.

OBJECTIVE: To determine whether serum neurofilament light (NfL) correlates with CSF NfL, traumatic brain injury (TBI) diagnosis, injury severity, brain volume, and diffusion tensor imaging (DTI) estimates of traumatic axonal injury (TAI). METHODS: Participants were prospectively enrolled in Sweden and the United States between 2011 and 2019. The Swedish cohort included 45 hockey players with acute concussion sampled at 6 days, 31 with repetitive concussion with persistent postconcussive symptoms (PCS) assessed with paired CSF and serum (median 1.3 years after concussion), 28 preseason controls, and 14 nonathletic controls. Our second cohort included 230 clinic-based participants (162 with TBI and 68 controls). Patients with TBI also underwent serum, functional outcome, and imaging assessments at 30 (n = 30), 90 (n = 48), and 180 (n = 59) days and 1 (n = 84), 2 (n = 57), 3 (n = 46), 4 (n = 38), and 5 (n = 29) years after injury. RESULTS: In athletes with paired specimens, CSF NfL and serum NfL were correlated (r = 0.71, p < 0.0001). CSF and serum NfL distinguished players with PCS >1 year from PCS ≤1 year (area under the receiver operating characteristic curve [AUROC] 0.81 and 0.80). The AUROC for PCS >1 year vs preseason controls was 0.97. In the clinic-based cohort, NfL at enrollment distinguished patients with mild from those with moderate and severe TBI (p < 0.001 and p = 0.048). Serum NfL decreased over the course of 5 years (ß = -0.09 log pg/mL, p < 0.0001) but remained significantly elevated compared to controls. Serum NfL correlated with measures of functional outcome, MRI brain atrophy, and DTI estimates of TAI. CONCLUSIONS: Serum NfL shows promise as a biomarker for acute and repetitive sports-related concussion and patients with subacute and chronic TBI. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that increased concentrations of NfL distinguish patients with TBI from controls.

Association of Angiotensin-Converting Enzyme Inhibitors with Increased Mortality Among Patients with Isolated Severe Traumatic Brain Injury.

BACKGROUND: Traumatic brain injury (TBI) is associated with one-third of all deaths from trauma. Preinjury exposure to cardiovascular drugs may affect TBI outcomes. Angiotensin-converting enzyme inhibitors (ACEIs) exacerbate brain cell damage and worsen functional outcomes in the laboratory setting. ß-blockers (BBs), however, appear to be associated with reduced mortality among patients with isolated TBI. OBJECTIVE: Examine the association between preinjury ACEI and BB use and clinical outcome among patients with isolated TBI. METHODS: A retrospective cohort study of patients age ≥ 40 years admitted to an academic level 1 trauma center with isolated TBI between January 2010 and December 2014 was performed. Isolated TBI was defined as a head Abbreviated Injury Scale (AIS) score ≥ 3, with chest, abdomen, and extremity AIS scores ≤ 2. Preinjury medication use was determined through chart review. All patients with concurrent BB use were initially excluded. In-hospital mortality was the primary measured outcome. RESULTS: Over the 5-year study period, 600 patients were identified with isolated TBI who were naive to BB use. There was significantly higher mortality (P = .04) among patients who received ACEI before injury (10 of 96; 10%) than among those who did not (25 of 504; 5%). A multivariate stepwise logistic regression analysis revealed a threefold increased risk of mortality in the ACEI cohort (P < .001), which was even greater than the twofold increased risk of mortality associated with an Injury Severity Score ≥ 16. A second analysis that included patients who received preinjury BBs (n = 98) demonstrated slightly reduced mortality in the ACEI cohort with only a twofold increased risk in multivariate analysis (P = .05). CONCLUSIONS: Preinjury exposure to ACEIs is associated with an increase in mortality among patients with isolated TBI. This effect is ameliorated in patients who receive BBs, which provides evidence that this class of medications may provide a protective benefit.

Characteristics of pedestrian head injuries observed from real world collision data.

Head injury is one of the most common injury types in vehicle-to-pedestrian collisions, which leads to death and long-term disabilities. However, detailed analysis of pedestrian head injuries in real world collisions is scarce. Thus the current study used two samples of 120 cases and 184 cases extracted from 1060 pedestrian collision cases captured during 2000-2015 from the GIDAS (German In-Depth-Accident Study) database to investigate the detailed characteristics of AIS2+ pedestrian head injuries. Firstly, the interrelationship between different head injury types (skull fracture, focal brain injury, concussion and diffuse axonal injury (DAI)) was analysed using the sample of 120 cases which each had at least one AIS2+ head injury. Then the influences of impact speed, pedestrian age and car front shape parameters on the injury risk of skull fracture, focal brain injury and concussion were assessed using the logistic regression method, based on the sample of 184 AIS1+ cases where the primary head contact location was within the windscreen glass area. The results show that: skull fractures and focal brain injuries dominate for AIS3+ head injuries and are generally associated with each other; concussion is the most important injury type for AIS2 head injuries and usually occurs in isolation. Further, for head impacts to the windscreen glass area a higher bonnet leading edge helps to reduce concussion odds, and none of the selected car front shape parameters are significant for the odds of skull fracture and focal brain injury, and vehicle impact speed and pedestrian age are insignificant for concussion. These detailed characteristics of pedestrian head injuries provide a basis for future pedestrian head injury prevention strategies with skull fractures and focal brain injuries being the most important injuries to address.

Traumatic Brain Injury Caused by Motor Vehicle Collision and Alcoholism in Piauí

Objectives To determine the relationship between alcohol consumption and the incidence of traumatic brain injury (TBI) with diffuse axonal injury (DAI), determining these indices, checking acquired comorbidities and characterizing the patients by gender, age and race/color, as well as describing the characteristics of the motor vehicle collision (vehicle, period of the day, day of the week and site) in people admitted to an emergency hospital in the city of Teresina, in the state of Piauí, Brazil. Methods We have analyzed the data contained in the medical records of patients admitted with a history of motor vehicle collision and severe TBI in intensive care units, based on the forms provided by the Mobile Emergency Care Service (SAMU, in the Portuguese acronym) in the period between February 28 and November 28, 2013. Results In the period covered by the present study, 200 individuals were analyzed, and 54 (27%) had consumed alcohol; of these 11 had DAI. Of the total sample, 17% (34) presented DAI, however, with unknown data regarding the consumption of alcoholic beverages. Conclusion Considering the data, we observed that the profile of the head trauma patients are brown men, mostly (53.5%) aged between 15 and 30 years. The collisions occurred mostly on weekends and at night (55%), and 89.5% of the crashes involved motorcycles.

Extended Anatomical Grading in Diffuse Axonal Injury Using MRI: Hemorrhagic Lesions in the Substantia Nigra and Mesencephalic Tegmentum Indicate Poor Long-Term Outcome.

Clinical outcome after traumatic diffuse axonal injury (DAI) is difficult to predict. In this study, three magnetic resonance imaging (MRI) sequences were used to quantify the anatomical distribution of lesions, to grade DAI according to the Adams grading system, and to evaluate the value of lesion localization in combination with clinical prognostic factors to improve outcome prediction. Thirty patients (mean 31.2 years ±14.3 standard deviation) with severe DAI (Glasgow Motor Score [GMS] <6) examined with MRI within 1 week post-injury were included. Diffusion-weighted (DW), T2*-weighted gradient echo and susceptibility-weighted (SWI) sequences were used. Extended Glasgow outcome score was assessed after 6 months. Number of DW lesions in the thalamus, basal ganglia, and internal capsule and number of SWI lesions in the mesencephalon correlated significantly with outcome in univariate analysis. Age, GMS at admission, GMS at discharge, and low proportion of good monitoring time with cerebral perfusion pressure <60 mm Hg correlated significantly with outcome in univariate analysis. Multivariate analysis revealed an independent relation with poor outcome for age (p = 0.005) and lesions in the mesencephalic region corresponding to substantia nigra and tegmentum on SWI (p = 0.008). We conclude that higher age and lesions in substantia nigra and mesencephalic tegmentum indicate poor long-term outcome in DAI. We propose an extended MRI classification system based on four stages (stage I-hemispheric lesions, stage II-corpus callosum lesions, stage III-brainstem lesions, and stage IV-substantia nigra or mesencephalic tegmentum lesions); all are subdivided by age (≥/<30 years).

Concussion, Diffuse Axonal Injury, and AIS4+ Head Injury in Motor Vehicle Crashes.

PURPOSE: This is a descriptive study of the annual incidence of brain injuries in motor vehicle crashes by type, seat belt use, and crash severity (delta V) using national accident data. The risk for concussion, diffuse axonal injury (DAI), and severe head injury was determined. METHODS: 1994-2011 NASS-CDS was analyzed to estimate the number of brain injuries annually in nonejected adults involved in motor vehicle crashes. Crashes were grouped by front, side, rear, and rollover, and the effect of belt use was investigated. Light vehicles were included with model year 1994+. Head injuries were identified as concussion, DAI, severe head injury (Abbreviated Injury Scale [AIS] 4+), and skull fracture. The annual incidence, risk, and rate for different types of head injury were estimated with standard errors. RESULTS: Motor vehicle crashes involved 33,191 ± 7,815 occupants with concussion, 5,665 ± 996 with AIS 4+ head injuries, 986 ± 446 with DAI, and 3,300 ± 531 with skull fracture annually. The risk was 1.64 ± 0.39% for concussion, 0.28 ± 0.05% for severe head injury (AIS 4+), 0.05 ± 0.02% for DAI, and 0.16 ± 0.03% for skull fracture in tow-away crashes. The risk for severe head injury (AIS 4+) was highest in rollovers (0.74 ± 0.16%) and lowest in rear impacts (0.17 ± 0.05%). Head injury risk depended on seat belt use, crash type, and crash severity (delta V). Seat belt use lowered the risk for AIS 4+ head injury by 74.8% and skull fracture by 73.2%. CONCLUSIONS: Concussions occur in about one out of 61 occupants in tow-away crashes. The risk was highest in rollover crashes (4.73 ± 1.09%) and it was reduced 69.2% by seat belt use. Severe brain injuries occurred less often and the risk was also reduced by seat belt use.

The effect of Boswellia Serrata on neurorecovery following diffuse axonal injury.

OBJECTIVES: This pilot trial was conducted to establish whether Boswellia Serrata (BS), a traditional herbal medicine, could improve the outcome of patients who have diffuse axonal injury (DAI). METHODS: In total, 38 patients with pure DAI were enrolled in this 12-week, double-blind, randomized, cross-over study. The patients were randomly assigned to receive either placebo (group A, n = 20) or BS capsules (group B, n = 18) for 6 weeks and then switched to the other intervention for another 6 weeks. The disability rating scale (DRS) was used to assess the outcome at 2-, 6- and 12-weeks post-trauma. RESULTS: A non-significant trend for improvement of DRS total scores was observed after the use of BS. Regarding the DRS sub-scores, however, there was significant improvement in 'cognitive ability to self-care' during the second 6 weeks in group A on BS compared to an insignificant spontaneous recovery in group B during the same period on placebo. Moreover, both groups experienced a close-to-significant increase in the cognitive function-related items of the DRS during the periods they were on BS. The reported adverse events were all of mild quality and had similar frequency between the groups. CONCLUSION: These results suggest that BS resin does not significantly affect general outcome, but may enhance the cognitive outcome of patients with DAI.

Acute alcohol intoxication, diffuse axonal injury and intraventricular bleeding in patients with isolated blunt traumatic brain injury.

OBJECTIVE: The influence of blood alcohol level (BAL) on outcome remains unclear. This study investigated the relationships between BAL, type and number of diffuse axonal injury (DAI), intraventricular bleeding (IVB) and 6-month outcome. METHODS: This study reviewed 419 patients with isolated blunt traumatic brain injury. First, it compared clinical and radiological characteristics between patients with good recovery and disability. Second, it compared BAL among DAI lesions. Third, it evaluated the correlation between the BAL and severity of IVB, number of DAI and corpus callosum injury lesions. RESULTS: Regardless of BAL, older age, male gender, severe Glasgow Coma Scale score (<9), abnormal pupil, IVB and lesion on genu of corpus callosum were significantly related to disability. There were no significant differences between the BAL and lesions of DAI. Simple regression analysis revealed that there were no significant correlation between BAL and severity of IVB, number of DAI and corpus callosum injury lesions. CONCLUSIONS: Acute alcohol intoxication was not associated with type and number of DAI lesion, IVB and disability. This study suggested that a specific type of traumatic lesion, specifically lesion on genu of corpus callosum and IVB, might be more vital for outcome.

Neuro-ophthalmic deficits after head trauma.

Head trauma can injure the afferent and/or efferent visual systems, resulting in neuro-ophthalmic deficits. When assessing afferent pathway injuries, a stepwise approach to evaluating visual acuity, pupils, color perception, and visual fields is critical. Traumatic optic neuropathy is of especial importance and its management must be tailored on a case-by-case basis. Efferent pathway injuries should be assessed with attention to abnormalities of ocular alignment and motility, which may occur as isolated deficits or as part of a recognizable syndrome. Concussion or diffuse axonal injuries may also affect ophthalmologic function. Here, we review the extant literature describing the assessment and acute treatment of traumatic neuro-ophthalmic deficits.

Criterios neurofisiológicos en el síndrome de Guillain-Barré infantil. Ocho años de experiencia / Electrodiagnostic criteria for childhood Guillain-Barré syndrome. Eight years’ experience

Introducción. El síndrome de Guillain-Barré es la causa más frecuente de parálisis flácida aguda en niños. Los criterios diagnósticos difieren según el subtipo, desmielinizante o axonal; y la prevalencia, por área geográfica. El estudio electromiográfico permite identificar variantes, valorar el pronóstico y predecir la evolución; es, además, una herramienta objetiva para el seguimiento. Objetivo. Describir las características electromiográficas de los casos de síndrome de Guillain-Barré valorados en el hospital y su clasificación por patrón fisiopatológico. Pacientes y métodos. Se incluyen todos los casos diagnosticados entre los años 2005 y 2012. Se realizaron estudios de conducción nerviosa motora y sensitiva y ondas F, en 14 niñas y 11 niños, entre 1 y 13 años de edad. Resultados. Se diagnosticaron 19 casos de polineuropatía desmielinizante inflamatoria aguda (AIDP) y cinco de neuropatía axonal motora aguda (AMAN). El electromiograma se realizó entre los días 1 y 30 tras el inicio de los síntomas. En los casos de AIDP, se objetivó desmielinización multifocal, cuatro de ellos con el sural preservado y 13 con alteración o ausencia de la onda F. En los casos de AMAN, cuatro tenían potenciales de baja amplitud y en uno no se evocaban. Conclusiones. La forma desmielinizante de la enfermedad es la más frecuente, aunque destaca el elevado número de casos de AMAN, en probable relación con la población objeto de estudio. La evolución fue favorable en tres casos de neuropatía axonal motora y en 15 de polineuropatía desmielinizante aguda. En cuatro casos se cronificaron los síntomas, tres de ellos con desmielinización persistente, hallazgo similar al de otros estudios en niños (AU)

Introduction. The Guillan-Barré syndrome is the most frequent case of acute flacid paralysis in children. The diagnostic criteria differ according to the demyelinating or axonal variant and the prevalence by geographical area. The electromyographic study permits identifying variants, evaluating the prognosis and predicting the evolution, is in addition an objective tool for the monitoring. Aim. To describe the electromyographic characteristics of the Guillain-Barré syndrome evaluated in hospital and its classification by physiopathological pattern. Patients and methods. All the cases diagnosed between 2005 and 2012 are included. Studies of motor and sensitive nervous conduction and F waves in 14 girls and 11 boys between 1 and 13 years of age. Results. 19 cases of acute inflammatory demyelinating polyneuropathy (AIDP) and five of acute motor axonal neuropathy (AMAN) were diagnosed. The electromyogram was performed between 1 and 30 days after the beginning of symptoms. In AIDP cases, multifocal demyelination, four of them with the preserved sural and 13 with alteration and absence of F wave were objectified. In the cases of AMAN, four had low amplitude potential and in one of them they were not evoked. Conclusions. The demyelinating form of the illness is the most frequent although the high number of AMAN cases stands out, probably related to the population object of study. The evolution was favorable in three cases of motor axonal neuropathy and in 15 accute demyelinating polyneuropathy. In four cases the symptoms became chronic; three of them with persistent demyelination a similar occurrence in other studies with children (AU)

Traumatic white matter injury and toxic leukoencephalopathies.

White matter injury may be secondary to a range of neurodegenerative disorders, such as the common dementing disorders of the elderly, or may be a consequence of specific white matter disorders, such as multiple sclerosis and the rare leukodystrophies. This article will focus on two relatively common primary groups of disorders of the white matter, traumatic white matter injury and toxic leukoencephalopathies. Traumatic axonal injury may be focal or diffuse, and is associated with a clinical spectrum ranging from concussion through to coma and death. The molecular mechanisms underlying axonal degeneration secondary to traumatic axonal degeneration are being elucidated and may give an insight into potential therapeutic targets. Toxic leukoencephalopathy may be secondary to exposure to a wide range of compounds, including chemotherapeutic drugs. These toxins may produce white matter injury through a range of mechanisms, and the potential toxic effects of compounds need to be considered when assessing a patient with a nonspecific leukoencephalopathy.

Haemorrhagic shearing lesions associated with diffuse axonal injury: application of T2 star-weighted angiography sequence in the detection and clinical correlation.

PURPOSE: To assess the diagnostic value of T2 star-weighted angiography (SWAN) sequence for diffuse axonal injury (DAI) by virtue of correlation analysis between the number, volume and regional distribution of haemorrhagic lesions determined with SWAN sequence and clinical variables. METHODS: Twenty-eight DAI patients were included in our study and were divided into subgroups in compliance with dichotomized clinical variables separately. Global and regional number, volume and distribution of haemorrhagic lesions were compared between groups by non-parametric Mann-Whitney U test (two tailed) and independent samples t test. Spearman's rank correlation analysis was performed to compare the dichotomized clinical variables with the global and regional number and volume of lesions. RESULTS: Patients with lower Glasgow Coma Scale (GCS) score (≤8, n = 16) or prolonged coma (>4 days, n = 15) or abnormal pupillary light reflex (PLR, n = 15) had a greater global number (p ≤ 0.01) and apparent volume (p ≤ 0.01) of haemorrhagic lesions. In our study, haemorrhage extent in most brain regions, such as frontal white matter (FW), parietotemporaloccipital white matter (PTOW), corpus callosum (CC), thalamus (THAL), brain stem (BS), were greater in the lower GCS group, in the prolonged coma group and in the abnormal PLR group (p ≤ 0.05). Significant correlations were found between haemorrhage extent in global range and the dichotomized clinical variables (p ≤ 0.01). Correlations were also found between haemorrhage extent in most regions, such as FW, PTOW, CC, THAL and BS, and the dichotomized clinical variables (p ≤ 0.05). The number of involved regions was much more higher in the lower GCS group and the prolonged coma group (p < 0.0001). CONCLUSION: More accurate and objective assessment of injury can be obtained in DAI patients via SWAN sequence.

Diffuse axonal injury in patients with head injuries: an epidemiologic and prognosis study of 124 cases.

BACKGROUND: Diffuse axonal injury (DAI) is usually associated to severe trauma. Recent imaging advances made its diagnosis easier. Its prognosis impact is not yet well established. The aim of this article is to describe the epidemiologic, clinical, and radiologic features of posttraumatic DAI and to study its prognosis impact on mortality and outcome according to Glasgow Outcome Scale. METHODS: This is a retrospective study over a 4-year period (2004-2007) of 124 patients admitted for head trauma. Demographic, clinical, biological, and radiologic findings were recorded at admission and during intensive care unit stay. RESULTS: Mean age (±standard deviation) was 28 years±15.8 years. Cranial computed tomography scan was sufficient enough to diagnose DAI in 31 patients. Magnetic resonance imaging was performed in 105 patients with a delay of 7.7 days±8.6 days. Most patients were classified as stage II (49.5%) or stage III (44.8%) according to Gentry's classification. In a multivariate analysis, factors associated with higher mortality were dysautonomia (p=0.018; odds ratio [OR]=4.17), hyperglycemia≥8 mmol/L (p=0.001; OR=3.84) on intensive care unit admission, and subdural hematoma (p=0.031; OR=3.99), whereas factors associated to poor outcome according to Glasgow Outcome Scale score were Glasgow Coma Scale score<8 (p=0.032, OR=3.55), secondary systemic injuries score≥3 (p=0.034, OR=2.83), hyperglycemia≥8 mmol/L (p=0.002, OR=5.55), and DAI count≥6 (p=0.035, OR=3.33). In patients with pure DAI, the absence of consciousness recovery was the unique independent factor of mortality (p<0.001, OR=116.4), whereas only transfusion need was an independent factor of poor outcome (p=0.017, OR=4.44). CONCLUSION: Dysautonomia, hyperglycemia, and subdural hematoma are the main factors associated to higher mortality when DAIs are diagnosed, whereas a DAI count≥6 is associated to poor outcome. Magnetic resonance imaging classification did not have a prognosis value even in patients with pure DAI.

Risk factors related to dysautonomia after severe traumatic brain injury.

BACKGROUND: Dysautonomia after severe traumatic brain injury (TBI) is a clinical syndrome affecting a subgroup of survivors and is characterized by episodes of autonomic dysregulation and muscle overactivity. The purpose of this study was to determine the incidence of dysautonomia after severe TBI in an intensive care unit setting and analyze the risk factors for developing dysautonomia. METHODS: A consecutive series of 101 patients with severe TBI admitted in a major trauma hospital during a 2-year period were prospectively observed to determine the effects of age, sex, mode of injury, hypertension history, admission systolic blood pressure, fracture, lung injury, admission Glasgow Coma Scale (GCS) score, injury severity score, emergency craniotomy, sedation or analgesia, diffuse axonal injury (DAI), magnetic resonance imaging (MRI) scales, and hydrocephalus on the development of dysautonomia. Risk factors for dysautonomia were evaluated by using logistic regression analysis. RESULTS: Seventy-nine of the 101 patients met inclusion criteria, and dysautonomia was observed in 16 (20.3%) of these patients. Univariate analysis revealed significant correlations between the occurrence of dysautonomia and patient age, admission GCS score, DAI, MRI scales, and hydrocephalus. Sex, mode of injury, hypertension history, admission systolic blood pressure, fracture, lung injury, injury severity score, sedation or analgesia, and emergency craniotomy did not influence the development of dysautonomia. Multivariate logistic regression revealed that patient age and DAI were two independent predictors of dysautonomia. There was no independent association between dysautonomia and admission GCS score, MRI scales, or hydrocephalus. CONCLUSIONS: Dysautonomia frequently occurs in patients with severe TBI. A younger age and DAI could be risk factors for facilitating the development of dysautonomia.

Prevalence and impact of diffuse axonal injury in patients with moderate and severe head injury: a cohort study of early magnetic resonance imaging findings and 1-year outcome.

OBJECT: In this prospective cohort study the authors examined patients with moderate to severe head injuries using MR imaging in the early phase. The objective was to explore the occurrence of diffuse axonal injury (DAI) and determine whether DAI was related to level of consciousness and patient outcome. METHODS: One hundred and fifty-nine patients (age range 5-65 years) with traumatic brain injury, who survived the acute phase, and who had a Glasgow Coma Scale (GCS) score of 3-13 were admitted between October 2004 and August 2008. Of these 159 patients, 106 were examined using MR imaging within 4 weeks postinjury. Patients were classified into 1 of 3 stages of DAI: Stage 1, in which lesions were confined to the lobar white matter; Stage 2, in which there were callosal lesions; and Stage 3, in which lesions occurred in the dorsolateral brainstem. The outcome measure used 12 months postinjury was the Glasgow Outcome Scale-Extended (GOSE). RESULTS: Diffuse axonal injury was detected in 72% of the patients and a combination of DAI and contusions or hematomas was found in 50%. The GCS score was significantly lower in patients with "pure DAI" (median GCS Score 9) than in patients without DAI (median GCS Score 12; p < 0.001). The GCS score was related to outcome only in those patients with DAI (r = 0.47; p = 0.001). Patients with DAI had a median GOSE score of 7, and patients without DAI had a median GOSE score of 8 (p = 0.10). Outcome was better in patients with DAI Stage 1 (median GOSE Score 8) and DAI Stage 2 (median GOSE Score 7.5) than in patients with DAI Stage 3 (median GOSE Score 4; p < 0.001). Thus, in patients without any brainstem injury, there was no difference in good recovery between patients with DAI (67%) and patients without DAI (66%). CONCLUSIONS: Diffuse axonal injury was found in almost three-quarters of the patients with moderate and severe head injury who survived the acute phase. Diffuse axonal injury influenced the level of consciousness, and only in patients with DAI was GCS score related to outcome. Finally, DAI was a negative prognostic sign only when located in the brainstem.

Association of contact loading in diffuse axonal injuries from motor vehicle crashes.

BACKGROUND: Although studies have been conducted to analyze brain injuries from motor vehicle crashes, the association of head contact has not been fully established. This study examined the association in occupants sustaining diffuse axonal injuries (DAIs). METHODS: The 1997 to 2006 motor vehicle Crash Injury Research Engineering Network database was used. All crash modes and all changes in velocity were included; ejections and rollovers were excluded; injuries to front and rear seat occupants with and without restraint use were considered. DAI were coded in the database using Abbreviated Injury Scale 1990. Loss of consciousness was included and head contact was based on medical- and crash-related data. RESULTS: Sixty-seven occupants with varying ages were coded with DAI. Forty-one adult occupants (mean, 33 years of age, 171-cm tall, 71-kg weight; 30 drivers, 11 passengers) were analyzed. Mean change in velocity was 41.2 km/h and Glasgow Coma Scale score was 4. There were 33 lateral, 6 frontal, and 2 rear crashes with 32 survivors and 9 were fatalities. Two occupants in the same crash did not sustain DAI. Although skull fractures and scalp injuries occurred in some impacts, head contact was identified in all frontal, rear, and far side, and all but one nearside crashes. CONCLUSIONS: Using a large sample size of occupants sustaining DAI in 1991 to 2006 model year vehicles, DAI occurred more frequently in side than frontal crashes, is most commonly associated with impact load transfer, and is not always accompanied by skull fractures. The association of head contact in >95% of cases underscores the importance of evaluating crash-related variables and medical information for trauma analysis. It would be prudent to include contact loading in addition to angular kinematics in the analysis and characterization of DAI.

Diffuse vascular injury in fatal road traffic accident victims: its relationship to diffuse axonal injury.

The authors have reported a macro- and microscopic study of brain lesions in 120 victims of fatal road traffic accidents, independent of the survival time. Diffuse vascular injury (DVI) was found in 14 patients (11.7%). All patients with DVI died within 24 h after the accident. The 14 patients with DVI also showed severe (Grade 2 or 3) diffuse axonal injury (DAI). Since DVI is restricted to road traffic accidents and incompatible with life, the high frequency observed in our series could be explained by the fact that all 120 patients were victims of road traffic accidents, and 69.2% had died within 24 h after the accident. The association between DVI and severe DAI (Grades 2 and 3) suggests that both lesions depend on the same mechanism, with the degree of axonal and vascular damage being determined by the intensity of the head acceleration. Our results show a relationship between DVI and DAI that suggest there may be a spectrum or at least a continuum between these entities as distinct from DVI being a separate entity.