The role of MR imaging in assessing prognosis after severe and moderate head injury

Serum assessment of traumatic axonal injury: the correlation of GFAP, t-Tau, UCH-L1, and NfL levels with diffusion tensor imaging metrics and its prognosis utility

OBJECTIVE

Diagnosis of traumatic axonal injury (TAI) is challenging because of its underestimation by conventional MRI and the technical requirements associated with the processing of diffusion tensor imaging (DTI). Serum biomarkers seem to be able to identify patients with abnormal CT scanning findings, but their potential role to assess TAI has seldomly been explored.

METHODS

Patients with all severities of traumatic brain injury (TBI) were prospectively included in this study between 2016 and 2021. They underwent blood extraction within 24 hours after injury and imaging assessment, including DTI. Serum concentrations of glial fibrillary acidic protein, total microtubule-associated protein (t-Tau), ubiquitin C-terminal hydrolase L1 (UCH-L1), and neurofilament light chain (NfL) were measured using an ultrasensitive Simoa multiplex assay panel, a digital form of enzyme-linked immunosorbent assay. The Glasgow Outcome Scale-Extended score was determined at 6 months after TBI. The relationships between biomarker concentrations, volumetric analysis of corpus callosum (CC) lesions, and fractional anisotropy (FA) were analyzed by nonparametric tests. The prognostic utility of the biomarker was determined by calculating the C-statistic and an ordinal regression analysis.

RESULTS

A total of 87 patients were included. Concentrations of all biomarkers were significantly higher for patients compared with controls. Although the concentration of the biomarkers was affected by the presence of mass lesions, FA of the CC was an independent factor influencing levels of UCH-L1 and NfL, which positioned these two biomarkers as better surrogates of TAI. Biomarkers also performed well in determining patients who would have had unfavorable outcome. NfL and the FA of the CC are independent complementary factors related to outcome.

CONCLUSIONS

UCH-L1 and NfL seem to be the biomarkers more specific to detect TAI. The concentration of NfL combined with the FA of the CC might help predict long-term outcome.

Imaging findings and outcomes after traumatic cerebellar injury: a canine case report

Background

Traumatic brain injury (TBI) is a structural injury or physiological disruption of the brain induced by an external force. The cerebellum facilitates movement coordination and provides a sense of equilibrium; damage to this structure can cause a wide variety of symptoms, including ataxia or dystaxia, ocular motor dysfunction, and disequilibrium. TBIs localised to the cerebellum are rare in dogs, and the prognosis following this type of injury remains unclear.

Case presentation

A 10-year-old female Chihuahua/Dachshund-cross dog weighing 2.8 kg presented after a fall of approximately 1 m the preceding night. The dog exhibited paresis of all limbs and was recumbent with constant extensor rigidity with opisthotonos. The bilateral thoracic limb and right pelvic limb spinal reflexes were exaggerated, while the left pelvic limb spinal reflexes were normal. The menace response was decreased, and vertical nystagmus was observed. Magnetic resonance imaging (MRI) revealed a hyperintense lesion on T2weighted (W) images, fluid-attenuated inversion recovery, and diffusion-weighted imaging (DWI). Mannitol and prednisolone were administered, and the dog recovered. The bilateral pelvic limb postural reactions improved by Day 16. On Day 22, MRI revealed a decrease in the hyperintense area of the T2W images, and this lesion appeared isointense on DWI.

Conclusions

In this case report, a dog with localised injury to the cerebellum that comprised a post-tentorial lesion recovered with a favourable outcome. Moreover, similar to reports in humans, DWI can help diagnose and evaluate TBI in dogs.

Prognosticating outcome using magnetic resonance imaging in patients with moderate to severe traumatic brain injury: a machine learning approach

INTRODUCTION

Over the last decade advancements in computer processing have enabled the application of machine learning (ML) to complex medical problems. Convolutional neural networks (CNN), a type of ML, have been used to interrogate medical images for variety of purposes. In this study, we aimed to investigate the potential application of CNN in prognosticating patients with traumatic brain injury (TBI).

METHODS

Patients with moderate to severe TBI and evidence of diffuse axonal injury (DAI) were selected retrospectively. A CNN model was developed using a training subgroup and a holdout subgroup was used as a testing dataset. We reported the model characteristics including area under the receiver operating characteristic curve (AUC).

RESULTS

We included a total of 38 patient, of which we generated 725 MRI sections. We developed a CNN model based on a modified AlexNet architecture that interpreted the brain stem injury to generate outcome predictions. The model was able to predict GOS outcomes with a specificity of 0.43 and a sensitivity of 0.997. It showed an AUC of 0.917.

CONCLUSION

The utilization of machine learning MRI analysis for prognosticating patients with TBI is a valued method that require further investigation. This will require multicentre collaboration to generate large datasets.

Traumatic axonal injury: is the prognostic information produced by conventional MRI and DTI complementary or supplementary?

OBJECTIVE

A traumatic axonal injury (TAI) diagnosis has traditionally been based on conventional MRI, especially on those sequences with a higher sensitivity to edema and blood degradation products. A more recent technique, diffusion tensor imaging (DTI), can infer the microstructure of white matter (WM) due to the restricted diffusion of water in organized tissues. However, there is little information regarding the correlation of the findings obtained by both methods and their use for outcome prognosis. The main objectives of this study were threefold: 1) study the correlation between DTI metrics and conventional MRI findings; 2) evaluate whether the prognostic information provided by the two techniques is supplementary or complementary; and 3) determine the incremental value of the addition of these variables compared to a traditional prognostic model.

METHODS

The authors studied 185 patients with moderate to severe traumatic brain injury (TBI) who underwent MRI with DTI study during the subacute stage. The number and volume of lesions in hemispheric subcortical WM, corpus callosum (CC), basal ganglia, thalamus, and brainstem in at least four conventional MRI sequences (T1-weighted, T2-weighted, FLAIR, T2* gradient recalled echo, susceptibility-weighted imaging, and diffusion-weighted imaging) were determined. Fractional anisotropy (FA) was measured in 28 WM bundles using the region of interest method. Nonparametric tests were used to evaluate the colocalization of macroscopic lesions and FA. A multivariate logistic regression analysis was performed to assess the independent prognostic value of each neuroimaging modality after adjustment for relevant clinical covariates, and the internal validation of the model was evaluated in a contemporary cohort of 92 patients.

RESULTS

Differences in the lesion load between patients according to their severity and outcome were found. Colocalization of macroscopic nonhemorrhagic TAI lesions (not microbleeds) and lower FA was limited to the internal and external capsule, corona radiata, inferior frontooccipital fasciculus, CC, and brainstem. However, a significant association between the FA value and the identification of macroscopic lesions in distant brain regions was also detected. Specifically, lower values of FA of some hemispheric WM bundles and the splenium of the CC were related to a higher number and volume of hyperintensities in the brainstem. The regression analysis revealed that age, motor score, hypoxia, FA of the genu of the CC, characterization of TAI lesions in the CC, and the presence of thalamic/basal ganglia lesions were independent prognostic factors. The performance of the proposed model was higher than that of the IMPACT (International Mission on Prognosis and Analysis of Clinical Trials in TBI) model in the validation cohort.

CONCLUSIONS

Very limited colocalization of hyperintensities (none for microbleeds) with FA values was discovered. DTI and conventional MRI provide complementary prognostic information, and their combination can improve the performance of traditional prognostic models.

Subcallosal haemorrhage as a sign of diffuse axonal injury in patients with traumatic brain injury

AIM

To identify the relationship between subcallosal haemorrhage and diffuse axonal injury (DAI) grading.

MATERIALS AND METHODS

Computed tomography (CT) and magnetic resonance imaging (MRI) images of all patients with traumatic brain injury over the past 5 years were reviewed. Subcallosal haemorrhage was defined as the presence of haemorrhage on admission CT underneath the corpus callosum. Grading of DAI was performed using MRI or CT exclusive of subcallosal haemorrhage status. The association of demographic factors, mechanism of injury, Glasgow Coma Scale (GCS) on admission, and positive subcallosal haemorrhage status with the presence of moderate-severe DAI was assessed. Receiver operating characteristic (ROC) curve analysis was used to evaluate the performance of subcallosal haemorrhage status in predicting DAI severity. Median modified Rankin Scale (mRS) scores were compared between subcallosal haemorrhage positive and negative cases.

RESULTS

The images of 1,150 patients were reviewed with 301 patients showing DAI. Of those, 64 patients (21.2%) and 237 patients (78.7%) were positive and negative for subcallosal haemorrhage, respectively. Isolated subcallosal haemorrhage was noted in 15 patients (23.4%). A subcallosal haemorrhage positive status (OR=5.16, p < 0.001) was statistically significantly associated with moderate-severe DAI. The ROC curve for predicting moderate-severe DAI with subcallosal haemorrhage status showed an area under the curve of 0.625 (95% confidence interval [CI]: 0.561-0.688, p < 0.001). The median mRS score was significantly higher (p < 0.001) in the subcallosal haemorrhage positive group (median 4.5, interquartile range [IQR] 2-6) versus the negative group (median 2, IQR 2-3). Isolated subcallosal haemorrhage group showed moderate-severe DAI in 80% (12/15) of cases.

CONCLUSION

Subcallosal haemorrhage is a highly specific radiographic predictor of moderate-severe DAI (grade 2-3).

Traumatic Microbleeds in the Hippocampus and Corpus Callosum Predict Duration of Posttraumatic Amnesia

OBJECTIVE

Radiologic predictors of posttraumatic amnesia (PTA) duration are lacking. We hypothesized that the number and distribution of traumatic microbleeds (TMBs) detected by gradient recalled echo (GRE) magnetic resonance imaging (MRI) predicts PTA duration.

SETTING

Academic, tertiary medical center.

PARTICIPANTS

Adults with traumatic brain injury (TBI).

DESIGN

We identified 65 TBI patients with acute GRE MRI. PTA duration was determined with the Galveston Orientation and Amnesia Test, Orientation Log, or chart review. TMBs were identified within memory regions (hippocampus, corpus callosum, fornix, thalamus, and temporal lobe) and control regions (internal capsule and global). Regression tree analysis was performed to identify radiologic predictors of PTA duration, controlling for clinical PTA predictors.

MAIN MEASURES

TMB distribution, PTA duration.

RESULTS

Sixteen patients (25%) had complicated mild, 4 (6%) had moderate, and 45 (69%) had severe TBI. Median PTA duration was 43 days (range, 0-240 days). In univariate analysis, PTA duration correlated with TMBs in the corpus callosum (R = 0.29, P = .02) and admission Glasgow Coma Scale (GCS) score (R = -0.34, P = .01). In multivariate regression analysis, admission GCS score was the only significant contributor to PTA duration. However, in regression tree analysis, hippocampal TMBs, callosal TMBs, age, and admission GCS score explained 26% of PTA duration variance and distinguished a subgroup with prolonged PTA.

CONCLUSIONS

Hippocampal and callosal TMBs are potential radiologic predictors of PTA duration.

[Clinical and MRI predictors of coma duration, intensive care and outcome of traumatic brain injury]

OBJECTIVE

This research is aimed to study the clinical and MRI predictors of coma duration, the intensity of critical care, and outcome of traumatic brain injury (TBI).

MATERIAL AND METHODS

The data from 309 patients with TBI of varying severity were included in the analysis, of whom 257 (86.7%) were treated in the intensive care unit (ICU), including 196 (63.4%) patients admitted in a comatose state lasting longer than 1 day. All patients underwent brain MRI within 21 days after the injury. MRI findings were classified according to MRI grading scale of brain damage level and localization proposed previously.

RESULTS

The proposed MRI grading significantly correlated with the Glasgow coma (GCS, r=-0.67; p<0.0001) and Glasgow outcome (0.69; p<0.001) scores in the entire group. In a subgroup of comatose patients (GCS<9) it correlated with coma duration (r=0.52; p<0.0001). Spearman correlation analysis showed a significant relationship between the MRI classification and a number of parameters: ICU length of stay (r=0.62; p<0.0001), the duration of artificial ventilation (r=0.47; p<0.0001), the rate of artificial ventilation, sedatives, analgesics, mannitol, hypertonic saline and vasopressors usage (p<0.01). These data confirm the relationship between higher grades of MRI classification (deep brain damage) and the need for the escalation of intensive care main components.

CONCLUSION

Our results support the hypothesis that the levels and localization of brain damage, estimated by the proposed MRI grading scale, might be predictors of coma duration, intensity and duration of intensive care, and TBI outcomes. A prognosis based on clinical and neuroimaging data comparison can be valuable for planning and efficient use of the hospital beds and ICU resources, for optimizing the patient flow and timing of patient transfer to neurorehabilitation facilities.

Early intervention combining Chinese and Western medicine in traumatic brain injury with diffuse axonal injury: A report of three cases

Background

Traumatic brain injury (TBI) is characterized by high prevalence, morbidity, and mortality. Diffuse axonal injury (DAI) is a specific type of TBI leading to prolonged consciousness impairment and disability. There is still no standard treatment for DAI, so we introduced traditional Chinese medicine into the treatment of these patients.

Case summaries

Three patients had TBI after traffic accidents. Their Glasgow Coma Scale (GCS) scores in the intensive care unit (ICU) were E₁V_EM₂-₃, E₁V_EM₂-₃, and E₁V_EM₂ respectively. All of them were diagnosed with DAI based on magnetic resonance imaging (MRI). Because of continuing consciousness disturbances, their families agreed to combine traditional Chinese medicine and modern medicine treatments through inpatient consultation in Taoyuan General hospital. Two patients took Buyang Huanwu Decoction, and one Tianma Gouteng Decoction twice a day. All of them received 20 min of acupuncture treatments 5 times per week. Acupuncture points included Baihui (GV20), Sishencong (EX-HN1), Shuigou (GV26), Hegu (LI4), and Taichong (LR3). All of them started Traditional Chinese medicine treatment within 2 weeks after TBI. The GCS of all three patients recovered to E₄M₅V₆.

Conclusions

The early addition of traditional Chinese medicine treatments to Western medical care can improve the prognosis of patients with diffuse axonal injury.

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Traumatic brain injury diagnosed with diffuse axonal injury, the lower GCS, the poorer outcome. This article points out that combining Chinese medicine and modern medicine can lead to better outcome(motor, speech function and GCS score).

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Chinese medicine has neuroprotective effect and it’s safe when combining with modern medicine in severe traumatic brain injury in this cases report.

Volume Change in Frontal Cholinergic Structures After Traumatic Brain Injury and Cognitive Outcome

The cholinergic nuclei in the basal forebrain innervate frontal cortical structures regulating attention. Our aim was to investigate if cognitive test results measuring attention relate to the longitudinal volume change of cholinergically innervated structures following traumatic brain injury (TBI). During the prospective, observational TBIcare project patients with all severities of TBI (n = 114) and controls with acute orthopedic injuries (n = 17) were recruited. Head MRI was obtained in both acute (mean 2 weeks post-injury) and late (mean 8 months) time points. T1-weighted 3D MR images were analyzed with an automatic segmentation method to evaluate longitudinal, structural brain volume change. The cognitive outcome was assessed with the Cambridge Neuropsychological Test Automated Battery (CANTAB). Analyses included 16 frontal cortical structures, of which four showed a significant correlation between post-traumatic volume change and the CANTAB test results. The strongest correlation was found between the volume loss of the supplementary motor cortex and motor screening task results (R-sq 0.16, p < 0.0001), where poorer test results correlated with greater atrophy. Of the measured sum structures, greater cortical gray matter atrophy rate showed a significant correlation with the poorer CANTAB test results. TBI caused volume loss of frontal cortical structures that are heavily innervated by cholinergic neurons is associated with neuropsychological test results measuring attention.

[The prognostic value of mri-classification of traumatic brain lesions level and localization depending on neuroimaging timing]

OBJECTIVE

The aim of this study was to estimate the prognostic value of magnetic resonance imaging (MRI) classification of traumatic brain lesion localization and levels in patients with a brain injury of various severity in a few days to three weeks after the injury.

MATERIAL AND METHODS

The cohort of 278 patients with traumatic brain injury (TBI) of various severity aged 8-74 y.o. (average -31.4±13.8, median - 29 (21.3; 37.0) was included in the analysis. The severity of TBI at admission varied from 3 to 15 Glasgow coma scores (GCS) (average - 8±4, median - 7 (5; 12). The main indications and conditions for MRI were: inconsistency between computed tomography (CT) data and neurological status, the necessity to clarify the location and type of brain damage, the absence of metal implants, the stabilization of the patient's vital functions, etc. MRI was performed during the first three weeks after the injury using T1, T2, T2-FLAIR, DWI, T2*GRE, SWAN sequences. The damage to the brain was classified according to 8 grades depending on the lesion levels (cortical-subcortical level, corpus callosum, basal ganglia and/or thalamus, and/or internal, and/or external capsules, uni- or bilateral brain stem injury at a different level). Outcomes were assessed by the Glasgow outcome scale (GOS) 6 months after injury.

RESULTS

The significant correlations were found for the entire cohort between MRI grading and TBI severity (by GCS) and outcome (by GOS) of the injury (R=-0.66; p<0.0001; R=-0.69; p<0.0001, respectively). A high accuracy (77%), sensitivity (77%) and specificity (76%) of the proposed MRI classification in predicting injury outcomes (AUC=0.85) were confirmed using the logistic regression and ROC analysis. The assessment of MRI-classification prognostic value in subgroups of patients examined during the first, second, and third weeks after injury showed significant correlations between the GCS and the GOS as well as between MRI-grading and GCS, and GOS in all three subgroups. In the subgroup of patients examined during the first 14 days after the injury, the correlation coefficients were higher compared with those obtained in a subgroup examined 15-21 days after the injury. The highest correlations between MRI grading, TBI severity, and the outcome were found in the subgroup of patients who underwent MRI in the first three days after the injury (n=58).

CONCLUSION

The proposed MRI classification of traumatic brain lesion levels and localization based on the use of different MR sequences reliably correlated with the clinical estimate of TBI severity by GCS and the outcomes by GOS in patients examined during the first three weeks after injury. The strongest correlation was observed for patients examined during the first three days after the injury.

Traumatic midline subarachnoid hemorrhage on initial computed tomography as a marker of severe diffuse axonal injury

OBJECTIVEThe objective of this study was to test the hypothesis that midline (interhemispheric or perimesencephalic) traumatic subarachnoid hemorrhage (tSAH) on initial CT may implicate the same shearing mechanism that underlies severe diffuse axonal injury (DAI).METHODSThe authors enrolled 270 consecutive patients (mean age [± SD] 43 ± 23.3 years) with a history of head trauma who had undergone initial CT within 24 hours and brain MRI within 30 days. Six initial CT findings, including intraventricular hemorrhage (IVH) and tSAH, were used as candidate predictors of DAI. The presence of tSAH was determined at the cerebral convexities, sylvian fissures, sylvian vallecula, cerebellar folia, interhemispheric fissure, and perimesencephalic cisterns. Following MRI, patients were divided into negative and positive DAI groups, and were assigned to a DAI stage: 1) stage 0, negative DAI; 2) stage 1, DAI in lobar white matter or cerebellum; 3) stage 2, DAI involving the corpus callosum; and 4) stage 3, DAI involving the brainstem. Glasgow Outcome Scale-Extended (GOSE) scores were obtained in 232 patients.RESULTSOf 270 patients, 77 (28.5%) had DAI; tSAH and IVH were independently associated with DAI (p < 0.05). Of tSAH locations, midline tSAH was independently associated with both overall DAI and DAI stage 2 or 3 (severe DAI; p < 0.05). The midline tSAH on initial CT had sensitivity of 60.8%, specificity of 81.7%, and positive and negative predictive values of 43.7% and 89.9%, respectively, for severe DAI. When adjusted for admission Glasgow Coma Score, the midline tSAH independently predicted poor GOSE score at both hospital discharge and after 6 months.CONCLUSIONSMidline tSAH could implicate the same shearing mechanism that underlies severe DAI, for which midline tSAH on initial CT is a probable surrogate.

Diffuse axonal injury (DAI) in moderate to severe head injured patients: Pure DAI vs. non-pure DAI

OBJECTIVE

Diffuse axonal injury (DAI) is known to be associated with poor outcome. DAI often associates with other intracranial injuries but their distinct features have not been established. In this retrospective cohort study, we compared clinical outcomes between pure and non-pure DAI patients.

PATIENTS AND METHODS

Total of 1047 traumatic brain injury (TBI) patients visited our institute between 2011 and 2017. Age ranged between 15-85 years old and Glasgow coma scale (GCS) score less than 13 were included. DAI was diagnosed in 45 patients using CT and MRI and their clinical features and outcomes were compared depending on their associated cranial injury; 20 patients without evidence of associated injury (Pure DAI group) and other 25 patients with associated injury (Non-pure DAI group). DAI stage was adopted using Gentry, L.R.

CLASSIFICATION

Glasgow outcome scale (GOS) was measured at least 6 months after trauma to evaluate their functional outcome.

RESULTS

The mean age and follow-up period were 45.36 years and 15.09 months, respectively. There were no significant differences between pure and non-pure DAI groups regarding demographic data and clinical findings on their admission. Logistic regression model was used to examine the association between GOS and clinical factors. In this analysis, pure DAI was no significantly different to non-pure DAI (p = 0.607). However, DAI Stage, transfusion, and hypotension on admission were strongly related to poor outcome. Stage III showed sevenfold higher risk when compared to Stage I (p = 0.010). The risk was also high when Stage III was compare to Stage I and II (p = 0.002). Interestingly, no significant difference was observed between Stage I and II (p = 0.847).

CONCLUSIONS

Unfavorable outcome was observed in 14 patients (31.11%) which was lower than we expected. Interestingly, non-pure DAI was no worse than pure DAI on their functional outcome. However, DAI Stage III was independently associated with poor outcome when compared to Stage I or I and II. Finally, we concluded that Stage II is clinically more related to Stage I, rather than Stage III.

Diffuse axonal injury after traumatic brain injury is a prognostic factor for functional outcome: a systematic review and meta-analysis

OBJECTIVE

To determine the prognosis of adult patients with traumatic brain injury (TBI) and diffuse axonal injury (DAI).

METHODS

Online search (PubMed, Embase and Ovid Science Direct) of articles providing information about outcome in (1) patients with DAI in general, (2) DAI vs. non-DAI, (3) related to magnetic resonance imaging (MRI) classification and (4) related to lesion location/load. A reference check and quality assessment were performed.

RESULTS

A total of 32 articles were included. TBI patients with DAI had a favourable outcome in 62%. The risk of unfavourable outcome in TBI with DAI was three times higher than in TBI without DAI. Odds ratio (OR) for unfavourable outcome was 2.9 per increase of DAI grade on MRI. Lesions located in the corpus callosum were associated with an unfavourable outcome. Other specific lesion locations and lesions count showed inconsistent results regarding outcome. Lesion volume was predictive for outcome only on apparent diffusion coefficient and fluid attenuation inversion recovery MRI sequences.

CONCLUSIONS

Presence of DAI on MRI in patients with TBI results in a higher chance of unfavourable outcome. With MRI grading, OR for unfavourable outcome increases threefold with every grade. Lesions in the corpus callosum in particular are associated with an unfavourable outcome.

The Prognostic Value of MRI in Moderate and Severe Traumatic Brain Injury: A Systematic Review and Meta-Analysis

OBJECTIVES

Traumatic brain injury is a major cause of death and disability, yet many predictors of outcome are not precise enough to guide initial clinical decision-making. Although increasingly used in the early phase following traumatic brain injury, the prognostic utility of MRI remains uncertain. We thus undertook a systematic review and meta-analysis of studies evaluating the predictive value of acute MRI lesion patterns for discriminating clinical outcome in traumatic brain injury.

DATA SOURCES

MEDLINE, EMBASE, BIOSIS, and CENTRAL from inception to November 2015.

STUDY SELECTION

Studies of adults who had MRI in the acute phase following moderate or severe traumatic brain injury. Our primary outcomes were all-cause mortality and the Glasgow Outcome Scale.

DATA EXTRACTION

Two authors independently performed study selection and data extraction. We calculated pooled effect estimates with a random effects model, evaluated the risk of bias using a modified version of Quality in Prognostic Studies and determined the strength of evidence with the Grading of Recommendations, Assessment, Development, and Evaluation.

DATA SYNTHESIS

We included 58 eligible studies, of which 27 (n = 1,652) contributed data to meta-analysis. Brainstem lesions were associated with all-cause mortality (risk ratio, 1.78; 95% CI, 1.01-3.15; I = 43%) and unfavorable Glasgow Outcome Scale (risk ratio, 2.49; 95% CI, 1.72-3.58; I = 81%) at greater than or equal to 6 months. Diffuse axonal injury patterns were associated with an increased risk of unfavorable Glasgow Outcome Scale (risk ratio, 2.46; 95% CI, 1.06-5.69; I = 74%). MRI scores based on lesion depth demonstrated increasing risk of unfavorable neurologic outcome as more caudal structures were affected. Most studies were at high risk of methodological bias.

CONCLUSIONS

MRI following traumatic brain injury yields important prognostic information, with several lesion patterns significantly associated with long-term survival and neurologic outcome. Given the high risk of bias in the current body of literature, large well-controlled studies are necessary to better quantify the prognostic role of early MRI in moderate and severe traumatic brain injury.

Medical Management of the Severe Traumatic Brain Injury Patient

Severe traumatic brain injury (sTBI) is a major contributor to long-term disability and a leading cause of death worldwide. Medical management of the sTBI patient, beginning with prehospital triage, is aimed at preventing secondary brain injury. This review discusses prehospital and emergency department management of sTBI, as well as aspects of TBI management in the intensive care unit where advances have been made in the past decade. Areas of emphasis include intracranial pressure management, neuromonitoring, management of paroxysmal sympathetic hyperactivity, neuroprotective strategies, prognostication, and communication with families about goals of care. Where appropriate, differences between the third and fourth editions of the Brain Trauma Foundation guidelines for the management of severe traumatic brain injury are highlighted.

Head Trauma

Head trauma is a common cause of significant morbidity and mortality in dogs and cats. Traumatic brain injury may occur after head trauma. Understanding the pathophysiology of primary and secondary injury after head trauma is essential for management. This article reviews the pathophysiology of head trauma, patient assessment and diagnostics, and treatment recommendations.

[Magnetic resonance in traumatic brain injury: A comparative study of the different conventional magnetic resonance imaging sequences and their diagnostic value in diffuse axonal injury]

OBJECTIVE

To compare the identification capability of traumatic axonal injury (TAI) by different sequences on conventional magnetic resonance (MR) studies in traumatic brain injury (TBI) patients.

MATERIAL AND METHODS

We retropectevely analyzed 264 TBI patients to whom a MR had been performed in the first 60 days after trauma. All clinical variables related to prognosis were registered, as well as the data from the initial computed tomography. The MR imaging protocol consisted of a 3-plane localizer sequence T1-weighted and T2-weighted fast spin-echo, FLAIR and gradient-echo images (GRET2*). TAI lesions were classified according to Gentry and Firsching classifications. We calculated weighted kappa coefficients and the area under the ROC curve for each MR sequence. A multivariable analyses was performed to correlate MR findings in each sequence with the final outcome of the patients.

RESULTS

TAI lesions were adequately visualized on T2, FLAIR and GRET2* sequences in more than 80% of the studies. Subcortical TAI lesions were well on FLAIR and GRET2* sequences visualized hemorrhagic TAI lesions. We saw that these MR sequences had a high inter-rater agreement for TAI diagnosis (0.8). T2 sequence presented the highest value on ROC curve in Gentry (0.68, 95%CI: 0.61-0.76, p<0.001, Nagerlkerke-R² 0.26) and Firsching classifications (0.64, 95%CI 0.57-0.72, p<0.001, Nagerlkerke-R² 0.19), followed by FLAIR and GRET2* sequences. Both classifications determined by each of these sequences were associated with poor outcome after performing a multivariable analyses adjusted for prognostic factors (p<0.02).

CONCLUSIONS

We recommend to perform conventional MR study in subacute phase including T2, FLAIR and GRET2* sequences for visualize TAI lesions. These MR findings added prognostic information in TBI patients.

Prognostic value of corpus callosum injuries in severe head trauma

BACKGROUND

This study was performed to investigate the relationship between corpus callosum (CC) injury and prognosis in traumatic axonal injury (TAI).

METHOD

We retrospectively reviewed 264 patients with severe head trauma who underwent a conventional MR imaging in the first 60 days after injury. They were selected from a prospectively collected database of 1048 patients with severe head trauma admitted in our hospital. TAI lesions were defined as areas of increased signal intensity on T2 and FLAIR or areas of decreased signal on gradient-echo T2. We attempted to determine whether any MR imaging findings of TAI lesions at CC could be related to prognosis. Neurological impairment was assessed at 1 year after injury by means of GOS-E (good outcome being GOS-E 4/5 and bad outcome being GOS-E <4). We adjusted the multivariable analysis for the prognostic factors according to the IMPACT studies: the Core model (age, motor score at admission, and pupillary reactivity) and the Extended model (including CT information and second insults).

RESULTS

We found 97 patients (37 %) with TAI at CC and 167 patients (63 %) without CC lesions at MR. A total of 62 % of the patients with CC lesions had poor outcome, whereas 38 % showed good prognosis. The presence of TAI lesions at the corpus callosum was associated with poor outcome 1 year after brain trauma (p < 0.001, OR 3.8, 95 % CI: 2.04-7.06). The volume of CC lesions measured on T2 and FLAIR sequences was negatively correlated with the GOS-E after adjustment for independent prognostic factors (p = 0.01, OR 2.23, 95 % CI:1.17-4.26). Also the presence of lesions at splenium was statistically related to worse prognosis (p = 0.002, OR 8.1, 95 % CI: 2.2-29.82). We did not find statistical significance in outcome between hemorrhagic and non-hemorrhagic CC lesions.

CONCLUSIONS

The presence of CC is associated with a poor outcome. The total volume of the CC lesion is an independent prognostic factor for poor outcome in severe head trauma.

Traumatic axonal injury: Relationships between lesions in the early phase and diffusion tensor imaging parameters in the chronic phase of traumatic brain injury

This prospective study of traumatic brain injury (TBI) patients investigates fractional anisotropy (FA) from chronic diffusion tensor imaging (DTI) in areas corresponding to persistent and transient traumatic axonal injury (TAI) lesions detected in clinical MRI from the early phase. Thirty-eight patients (mean 24.7 [range 13-63] years of age) with moderate-to-severe TBI and 42 age- and sex-matched healthy controls were included. Patients underwent 1.5-T clinical MRI in the early phase (median 7 days), including fluid-attenuated inversion recovery (FLAIR) and T2* gradient echo (T2*GRE) sequences. TAI lesions from the early phase were characterized as nonhemorrhagic or microhemorrhagic. In the chronic phase (median 3 years), patients and controls were imaged at 3 T with FLAIR, T2*GRE, T1, and DTI sequences. TAI lesions were classified as transient or persistent. The FLAIR/T2*GRE images from the early phase were linearly registered to the FA images from the chronic phase and lesions manually segmented on the FA-registered FLAIR/T2*GRE images. For regions of interest (ROIs) from both nonhemorrhagic and microhemorrhagic lesion, we found a significant linear trend of lower mean FA from ROIs in healthy controls to ROIs in patients without either nonhemorrhagic or microhemorrhagic lesions and further to transient and finally persistent lesion ROIs (P < 0.001). Histogram analyses showed lower FA in persistent compared with transient nonhemorrhagic lesion ROIs (P < 0.001), but this was not found in microhemorrhagic lesion ROIs (P = 0.08-0.55). The demonstrated linear trend of lower FA values from healthy controls to persistent lesion ROIs was found in both nonhemorrhagic and microhemorrhagic lesions and indicates a gradual increasing disruption of the microstructure. Lower FA values in persistent compared with transient lesions were found only in nonhemorrhagic lesions. Thus, clinical MRI techniques are able to depict important aspects of white matter pathology across the stages of TBI. © 2016 Wiley Periodicals, Inc.

Computed tomography vs magnetic resonance imaging for identifying acute lesions in pediatric traumatic brain injury

BACKGROUND AND OBJECTIVE

Pediatric traumatic brain injury (TBI) is a leading cause of morbidity and mortality in children. Computed tomography (CT) is the modality of choice to screen for brain injuries. MRI may provide more clinically relevant information. The purpose of this study was to compare lesion detection between CT and MRI after TBI.

METHODS

Retrospective cohort of children (0-21 years) with TBI between 2008 and 2010 at a Level 1 pediatric trauma center with a head CT scan on day of injury and a brain MRI scan within 2 weeks of injury. Agreement between CT and MRI was determined by κ statistic and stratified by injury mechanism.

RESULTS

One hundred five children were studied. Of these, 78% had mild TBI. The MRI scan was obtained a median of 1 day (interquartile range, 1-2) after CT. Overall, CT and MRI demonstrated poor agreement (κ=-0.083; P=.18). MRI detected a greater number of intraparenchymal lesions (n=36; 34%) compared with CT (n=16; 15%) (P<.001). Among patients with abusive head trauma, MRI detected intraparenchymal lesions in 16 (43%), compared with only 4 (11%) lesions with CT (P=.03). Of 8 subjects with a normal CT scan, 6 out of 8 had abnormal lesions on MRI.

CONCLUSIONS

Compared with CT, MRI identified significantly more intraparenchymal lesions in pediatric TBI, particularly in children with abusive head trauma. The prognostic value of identification of intraparenchymal lesions by MRI is unknown but warrants additional inquiry. Risks and benefits from early MRI (including sedation, time, and lack of radiation exposure) compared with CT should be weighed by clinicians.

Radiologic Determination of Corpus Callosum Injury in Patients with Mild Traumatic Brain Injury and Associated Clinical Characteristics

Objective

To investigate the incidence of corpus callosum injury (CCI) in patients with mild traumatic brain injury (TBI) using brain MRI. We also performed a review of the clinical characteristics associated with this injury.

Methods

A total of 356 patients in the study were diagnosed with TBI, with 94 patients classified as having mild TBI. We included patients with mild TBI for further evaluation if they had normal findings via brain computed tomography (CT) scans and also underwent brain MRI in the acute phase following trauma. As assessed by brain MRI, CCI was defined as a high-signal lesion in T2 sagittal images and a corresponding low-signal lesion as determined by axial gradient echo (GRE) imaging. Based on these criteria, we divided patients into two groups for further analysis : Group I (TBI patients with CCI) and Group II (TBI patients without CCI).

Results

A total of 56 patients were enrolled in this study (including 16 patients in Group I and 40 patients in Group II). Analysis of clinical symptoms revealed a significant difference in headache severity between groups. Over 50% of patients in Group I experienced prolonged neurological symptoms including dizziness and gait disturbance and were more common in Group I than Group II (dizziness : 37 and 12% in Groups I and II, respectively; gait disturbance : 12 and 0% in Groups I and II, respectively).

Conclusion

The incidence of CCI in patients with mild TBI was approximately 29%. We suggest that brain MRI is a useful method to reveal the cause of persistent symptoms and predict clinical prognosis.

Predicting Outcome after Pediatric Traumatic Brain Injury by Early Magnetic Resonance Imaging Lesion Location and Volume

Brain lesions after traumatic brain injury (TBI) are heterogeneous, rendering outcome prognostication difficult. The aim of this study is to investigate whether early magnetic resonance imaging (MRI) of lesion location and lesion volume within discrete brain anatomical zones can accurately predict long-term neurological outcome in children post-TBI. Fluid-attenuated inversion recovery (FLAIR) MRI hyperintense lesions in 63 children obtained 6.2±5.6 days postinjury were correlated with the Glasgow Outcome Scale Extended-Pediatrics (GOS-E Peds) score at 13.5±8.6 months. FLAIR lesion volume was expressed as hyperintensity lesion volume index (HLVI)=(hyperintensity lesion volume / whole brain volume)×100 measured within three brain zones: zone A (cortical structures); zone B (basal ganglia, corpus callosum, internal capsule, and thalamus); and zone C (brainstem). HLVI-total and HLVI-zone C predicted good and poor outcome groups (p<0.05). GOS-E Peds correlated with HLVI-total (r=0.39; p=0.002) and HLVI in all three zones: zone A (r=0.31; p<0.02); zone B (r=0.35; p=0.004); and zone C (r=0.37; p=0.003). In adolescents ages 13-17 years, HLVI-total correlated best with outcome (r=0.5; p=0.007), whereas in younger children under the age of 13, HLVI-zone B correlated best (r=0.52; p=0.001). Compared to patients with lesions in zone A alone or in zones A and B, patients with lesions in all three zones had a significantly higher odds ratio (4.38; 95% confidence interval, 1.19-16.0) for developing an unfavorable outcome.

Guidelines for the management of severe head injury. Part 1. Neurotrauma system and neuroimaging

Traumatic brain injury is one of the main causes of mortality and disability in young and middle-aged individuals. The patients with severe traumatic brain injury who are in coma are the most difficult to deal with. Appropriate diagnosis of the primary brain injuries and early prevention and treatment of secondary damage mechanisms largely determine the possibility of reducing mortality and severe disabling consequences. The authors compiled these guidelines based on their experience in development of international and Russian recommendations on the diagnosis and treatment of mild traumatic brain injury, penetrating gunshot injury of the skull and brain, severe traumatic brain injury, and severe consequences of brain injuries, including a vegetative state. In addition, we used the materials of international and Russian recommendations on the diagnosis, intensive care, and surgical treatment of severe traumatic brain injury published in recent years. The proposed recommendations are related to organization of medical care and diagnosis of severe traumatic brain injury in adults and are primarily addressed to neurosurgeons, neurologists, neuroradiologists, anesthesiologists, and emergency room doctors, who are routinely involved in management of these patients.

Intraventricular hemorrhage on initial computed tomography as marker of diffuse axonal injury after traumatic brain injury

Intraventricular hemorrhage (IVH) on initial computed tomography (CT) was reported to predict lesions of diffuse axonal injury (DAI) in the corpus callosum (CC) on subsequent magnetic resonance imaging (MRI). We aimed to examine the relationship between initial CT findings and DAI lesions detected on MRI as well as the relationship between the severity of IVH (IVH score) and severity of DAI (DAI staging). A consecutive 140 patients with traumatic brain injury (TBI) who underwent MRI within 30 days after onset were revisited. We reviewed their initial CT for the following six findings: Status of basal cistern, status of mid-line shift, epidural hematoma, IVH, subarachnoid hemorrhage, and volume of hemorrhagic mass and IVH score were assigned in each patient. Based on MRI findings, patients were divided into DAI and non-DAI groups and were assigned a DAI staging. Then, to confirm that the IVH on initial CT predicts DAI lesions on MRI, we used multi-variate analysis of the six CT findings, including IVH, and examined the relationship between IVH score and DAI staging. The IVH detected on CT was the only predictor of DAI (p=0.0139). The IVH score and DAI staging showed significant positive correlation (p<0.0003). IVH score in DAI stage 3 (with DAI involving the brain stem; p=0.0025) or stage 2 (with DAI involving CC; p=0.0042) was significantly higher than that of DAI stage 0 (no DAI lesions). In conclusion, IVH on initial CT is the only marker of DAI on subsequent MRI, specifically severe DAI (stage 2 or 3).

Unexpected recovery of function after severe traumatic brain injury: the limits of early neuroimaging-based outcome prediction

BACKGROUND

Prognostication in the early stage of traumatic coma is a common challenge in the neuro-intensive care unit. We report the unexpected recovery of functional milestones (i.e., consciousness, communication, and community reintegration) in a 19-year-old man who sustained a severe traumatic brain injury. The early magnetic resonance imaging (MRI) findings, at the time, suggested a poor prognosis.

METHODS

During the first year of the patient's recovery, MRI with diffusion tensor imaging and T2*-weighted imaging was performed on day 8 (coma), day 44 (minimally conscious state), day 198 (post-traumatic confusional state), and day 366 (community reintegration). Mean apparent diffusion coefficient (ADC) and fractional anisotropy values in the corpus callosum, cerebral hemispheric white matter, and thalamus were compared with clinical assessments using the Disability Rating Scale (DRS).

RESULTS

Extensive diffusion restriction in the corpus callosum and bihemispheric white matter was observed on day 8, with ADC values in a range typically associated with neurotoxic injury (230-400 × 10(-6 )mm(2)/s). T2*-weighted MRI revealed widespread hemorrhagic axonal injury in the cerebral hemispheres, corpus callosum, and brainstem. Despite the presence of severe axonal injury on early MRI, the patient regained the ability to communicate and perform activities of daily living independently at 1 year post-injury (DRS = 8).

CONCLUSIONS

MRI data should be interpreted with caution when prognosticating for patients in traumatic coma. Recovery of consciousness and community reintegration are possible even when extensive traumatic axonal injury is demonstrated by early MRI.

Prognostic value of early magnetic resonance imaging in dogs after traumatic brain injury: 50 cases

BACKGROUND

The prognostic value of early magnetic resonance imaging (MRI) in dogs after traumatic brain injury (TBI) remains unclear.

OBJECTIVES

Determine whether MRI findings are associated with prognosis after TBI in dogs.

ANIMALS

Fifty client-owned dogs.

METHODS

Retrospective study of dogs with TBI that underwent 1.5T MRI within 14 days after head trauma. MRI evaluators were blinded to the clinical presentation, and all images were scored based on an MRI grading system (Grade I [normal brain parenchyma] to Grade VI [bilateral lesions affecting the brainstem with or without any lesions of lesser grade]). Skull fractures, percentage of intraparenchymal lesions, degree of midline shift, and type of brain herniation were evaluated. MGCS was assessed at presentation. The presence of seizures was recorded. Outcome was assessed at 48 h (alive or dead) and at 3, 6, 12, and 24 months after TBI.

RESULTS

Sixty-six percent of the dogs had abnormal MRI findings. MRI grade was negatively correlated (P < .001) with MGCS. A significant negative correlation of MRI grade, degree of midline shift, and percentage of intraparenchymal lesions with follow-up scores was identified. The MGCS was lower in dogs with brain herniation (P = .0191). Follow-up scores were significantly lower in dogs that had brain herniation or skull fractures. The possibility of having seizures was associated with higher percentage of intraparenchymal lesions (P = 0.0054) and 10% developed PTE.

CONCLUSIONS AND CLINICAL IMPORTANCE

Significant associations exist between MRI findings and prognosis in dogs with TBI. MRI can help to predict prognosis in dogs with TBI.

Functional MRI and outcome in traumatic coma

Advances in task-based functional MRI (fMRI), resting-state fMRI (rs-fMRI), and arterial spin labeling (ASL) perfusion MRI have occurred at a rapid pace in recent years. These techniques for measuring brain function have great potential to improve the accuracy of prognostication for civilian and military patients with traumatic coma. In addition, fMRI, rs-fMRI, and ASL perfusion MRI have provided novel insights into the pathophysiology of traumatic disorders of consciousness, as well as the mechanisms of recovery from coma. However, functional neuroimaging techniques have yet to achieve widespread clinical use as prognostic tests for patients with traumatic coma. Rather, a broad spectrum of methodological hurdles currently limits the feasibility of clinical implementation. In this review, we discuss the basic principles of fMRI, rs-fMRI, and ASL perfusion MRI and their potential applications as prognostic tools for patients with traumatic coma. We also discuss future strategies for overcoming the current barriers to clinical implementation.

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.

Parent perceptions of early prognostic encounters following children's severe traumatic brain injury: 'locked up in this cage of absolute horror'

OBJECTIVE

Little guidance exists for discussing prognosis in early acute care with parents following children's severe traumatic brain injury (TBI). Providers' beliefs about truth-telling can shape what is said, how it is said and how providers respond to parents.

METHODS

This study was part of a large qualitative study conducted in the US (42 parents/37 families) following children's moderate-to-severe TBI (2005-2007). Ethnography of speaking was used to analyse interviews describing early acute care following children's severe TBI (29 parents/25 families).

RESULTS

Parents perceived that: (a) parents were disadvantaged by provider delivery; (b) negative outcome values dominated some provider's talk; (c) truth-telling involves providers acknowledging all possibilities; (d) framing the child's prognosis with negative medical certainty when there is some uncertainty could damage parent-provider relationships; (e) parents needed to remain optimistic; and (f) children's outcomes could differ from providers' early acute care prognostications.

CONCLUSION

Parents blatantly and tacitly revealed their beliefs that providers play an important role in shaping parent reception of and synthesis of prognostic information, which constructs the family's ability to cope and participate in shared decision-making. Negative medical certainty created a fearful or threatening environment that kept parents from being fully informed.

Prognosis in prolonged coma patients with diffuse axonal injury assessed by somatosensory evoked potentia

A total of 43 prolonged coma patients with diffuse axonal injury received the somatosensory evoked potential examination one month after injury in the First Affiliated Hospital, School of Medicine, Zhejiang University in China. Somatosensory evoked potentials were graded as normal, abnormal or absent (grades I–III) according to N20 amplitude and central conduction time. The outcome in patients with grade III somatosensory evoked potential was in each case unfavorable. The prognostic accuracy of grade III somatosensory evoked potential for unfavorable and non-awakening outcome was 100% and 80%, respectively. The prognostic accuracy of grade I somatosensory evoked potential for favorable and wakening outcome was 86% and 100%, respectively. These results suggest that somatosensory evoked potential grade is closely correlated with coma severity and degree of recovery. Somatosensory evoked potential is a valuable diagnostic tool to assess prognosis in prolonged coma patients with diffuse axonal injury.

Advanced neuroimaging in traumatic brain injury

Advances in structural and functional neuroimaging have occurred at a rapid pace over the past two decades. Novel techniques for measuring cerebral blood flow, metabolism, white matter connectivity, and neural network activation have great potential to improve the accuracy of diagnosis and prognosis for patients with traumatic brain injury (TBI), while also providing biomarkers to guide the development of new therapies. Several of these advanced imaging modalities are currently being implemented into clinical practice, whereas others require further development and validation. Ultimately, for advanced neuroimaging techniques to reach their full potential and improve clinical care for the many civilians and military personnel affected by TBI, it is critical for clinicians to understand the applications and methodological limitations of each technique. In this review, we examine recent advances in structural and functional neuroimaging and the potential applications of these techniques to the clinical care of patients with TBI. We also discuss pitfalls and confounders that should be considered when interpreting data from each technique. Finally, given the vast amounts of advanced imaging data that will soon be available to clinicians, we discuss strategies for optimizing data integration, visualization, and interpretation.

Prediction of outcome after traumatic brain injury using clinical and neuroimaging variables

Background and Purpose

The functional outcome of traumatic brain injury (TBI) varies widely. The aim of this study was to identify the factors predicting outcome following TBI.

Methods

We prospectively enrolled acute TBI patients, and assessed them clinically and radiologically using brain magnetic resonance imaging (MRI). Functional outcome was measured using the Glasgow Outcome Scale (GOS) at 3 months after TBI. A GOS score of ≤4 was regarded as an unfavorable outcome. We performed multivariate analysis to investigate the association between clinicoradiological variables and outcome.

Results

Forty-two patients completed the clinical evaluation in the acute phase and outcome measurement at 3 months. Motorcycle accident was associated with unfavorable outcome [odds ratio (OR)=38.3, p=0.022]. If the patients were the victims of the accident, they were more likely to have an unfavorable outcome (OR=21.3, p=0.037). All seven patients with a low Glasgow Coma Scale (GCS) score (i.e., ≤8) at 24 or 48 h after TBI were also found to have an unfavorable outcome. The presence of diffuse axonal injury (DAI) was a significant predicting factor of an unfavorable outcome (OR=8.48, p=0.042).

Conclusions

Motorcycle accident, being an accident victim, and a lower GCS score at 24 hours or more after the accident were found to be unfavorable prognostic variables. DAI was the only radiologic variable predicting an unfavorable outcome. Thus, it is important to identify DAI by applying MRI in the acute phase.

Outcome prediction within twelve hours after severe traumatic brain injury by quantitative cerebral blood flow

We measured quantitative cortical mantle cerebral blood flow (CBF) by stable xenon computed tomography (CT) within the first 12 h after severe traumatic brain injury (TBI) to determine whether neurologic outcome can be predicted by CBF stratification early after injury. Stable xenon CT was used for quantitative measurement of CBF (mL/100 g/min) in 22 cortical mantle regions stratified as follows: low (0-8), intermediate (9-30), normal (31-70), and hyperemic (>70) in 120 patients suffering severe (Glasgow Coma Scale [GCS] score ≤8) TBI. For each of these CBF strata, percentages of total cortical mantle volume were calculated. Outcomes were assessed by Glasgow Outcome Scale (GOS) score at discharge (DC), and 1, 3, and 6 months after discharge. Quantitative cortical mantle CBF differentiated GOS 1 and GOS 2 (dead or vegetative state) from GOS 3-5 (severely disabled to good recovery; p<0.001). Receiver operating characteristic (ROC) curve analysis for percent total normal plus hyperemic flow volume (TNHV) predicting GOS 3-5 outcome at 6 months for CBF measured <6 and <12 h after injury showed ROC area under the curve (AUC) cut-scores of 0.92 and 0.77, respectively. In multivariate analysis, percent TNHV is an independent predictor of GOS 3-5, with an odds ratio of 1.460 per 10 percentage point increase, as is initial GCS score (OR=1.090). The binary version of the Marshall CT score was an independent predictor of 6-month outcome, whereas age was not. These results suggest that quantitative cerebral cortical CBF measured within the first 6 and 12 h after TBI predicts 6-month outcome, which may be useful in guiding patient care and identifying patients for randomized clinical trials. A larger multicenter randomized clinical trial is indicated.

Intraventricular hemorrhage on computed tomography and corpus callosum injury on magnetic resonance imaging in patients with isolated blunt traumatic brain injury

OBJECT

Intraventricular hemorrhage (IVH) is widely regarded as one element of a complex involving severe blunt traumatic brain injury (TBI); corpus callosum injury (CCI) is recently considered to be one factor associated with poor outcome in patients with TBI. Although postmortem studies have focused on the relationship between IVH and CCI, there have been few investigations of IVH evidenced on CT scans as a predictor of CCI evidenced on MRI.

METHODS

The authors retrospectively reviewed prospectively collected data from 371 patients with blunt TBI, without trauma to the face, chest, abdomen, extremities, or pelvic girdle, requiring immediate therapeutic intervention. Their aim was to investigate whether IVH found on CT predicts CCI on MRI. Clinical and radiological data were collected between June 2003 and February 2011. First, the authors classified patients into groups of those with CCI and those without CCI, and they compared clinical and radiological findings between them. Then, they investigated prognostic factors that were related to the development of disability at 6 months after injury. The outcomes at 6 months after injury were evaluated using the Extended Glasgow Outcome Scale (GOS-E). Finally, the authors evaluated the correlation between the severity of the IVH on CT and the number of CCI lesions on MRI. The severity of the IVH was defined by the number of ventricles in which IVH was seen, and the number of CCI lesions was counted on the MRI study.

RESULTS

On multivariate logistic regression analysis, Glasgow Coma Scale score less than 9 (OR 2.70 [95% CI 1.10-6.27]), traffic accident (OR 2.59 [95% CI 1.37-4.93]), and IVH on CT (OR 3.31 [95% CI 1.25-8.49]) were significantly related to CCI. Multivariate analysis also showed that older age (p = 0.0001), male sex (OR 3.26 [95% CI 1.46-8.08], p = 0.0065), Glasgow Coma Scale score less than 9 (OR 8.27 [95% CI 3.39-21.4], p < 0.0001), evidence of IVH on CT (OR 4.09 [95% CI 1.45-11.9], p = 0.0081), and evidence of CCI on MRI (OR 8.32 [95% CI 3.89-18.8], p < 0.0001) were associated with future development of disability (GOS-E score ≤ 6). Furthermore, simple regression analysis revealed the existence of a strong correlation between the severity of IVH and the number of CCI lesions (r = 0.0668, p = 0.0022).

CONCLUSIONS

The authors' results suggest that evidence of IVH on CT may indicate CCI, which can lead to disability in patients with isolated blunt TBI.

Severe traumatic head injury: prognostic value of brain stem injuries detected at MRI

BACKGROUND AND PURPOSE

Traumatic brain injuries represent an important cause of death for young people. The main objectives of this work are to correlate brain stem injuries detected at MR imaging with outcome at 6 months in patients with severe TBI, and to determine which MR imaging findings could be related to a worse prognosis.

MATERIALS AND METHODS

One hundred and eight patients with severe TBI were studied by MR imaging in the first 30 days after trauma. Brain stem injury was categorized as anterior or posterior, hemorrhagic or nonhemorrhagic, and unilateral or bilateral. Outcome measures were GOSE and Barthel Index 6 months postinjury. The relationship between MR imaging findings of brain stem injuries, outcome, and disability was explored by univariate analysis. Prognostic capability of MR imaging findings was also explored by calculation of sensitivity, specificity, and area under the ROC curve for poor and good outcome.

RESULTS

Brain stem lesions were detected in 51 patients, of whom 66% showed a poor outcome, as expressed by the GOSE scale. Bilateral involvement was strongly associated with poor outcome (P < .05). Posterior location showed the best discriminatory capability in terms of outcome (OR 6.8, P < .05) and disability (OR 4.8, P < .01). The addition of nonhemorrhagic and anterior lesions or unilateral injuries showed the highest odds and best discriminatory capacity for good outcome.

CONCLUSIONS

The prognosis worsens in direct relationship to the extent of traumatic injury. Posterior and bilateral brain stem injuries detected at MR imaging are poor prognostic signs. Nonhemorrhagic injuries showed the highest positive predictive value for good outcome.

Cranial computed tomography scan findings in head trauma patients in Enugu, Nigeria

Background:

The choice of radiological investigations in head trauma in Africa is influenced by factors such as cost. Some patients who require computed tomography (CT) scan elsewhere are either managed blindly or do not present for it at the appropriate time. This paper evaluates the CT scan findings as they are obtained in cases of head trauma in a region of Nigeria.

Methods:

Prospectively recorded data of all head injury patients who presented for CT scan between January 2009 and April 2010 at Memfys Hospital for Neurosurgery (MHN), Enugu, Nigeria, were analyzed. Mobile CereTom 8-Slice CT was used in all cases. New and follow-up cases were included.

Results:

There were 204 CT scans for head trauma (171 new, 33 follow-up), accounting for about 34% of all head CT scans performed with this unit. The male to female ratio was 3.5:1. About 33.9% of the patients were in the third and fourth decades of life. In 19.9% cases, CT was unremarkable, while 80.1% cases had abnormal CT findings. The CT diagnosis was not in keeping with the indication of head trauma in 7%, and 13% had more than one finding. The most common CT findings were: subdural hematoma 30%, cerebral contusions and edema 30.7%, skull fractures 23.4% and extradural hematoma 8.0%. About 64% of the CT findings required surgical interventions. The overall mortality was 11.1%, but amongst the 137 patients who had abnormal CT findings, it was 13.9%.

Conclusion:

The high yield and diversity of CT scan findings in head trauma patients support the indication for the appropriate use of CT in diagnosis and management of head trauma even in developing countries.

Neuropathological findings in disabled survivors of a head injury

We investigated how the occurrence and severity of the main neuropathological types of traumatic brain injury (TBI) influenced the severity of disability after a head injury. Eighty-five victims, each of whom had lived at least a month after a head injury but then died, were studied. Judged by the Glasgow Outcome Scale (GOS), before death 35 were vegetative, 30 were severely and 20 were moderately disabled. Neuropathological assessment showed that 71 (84%) victims had sustained cerebral contusions, 49 (58%) had diffuse axonal injury (DAI), 57 (67%), had ischemic brain damage (IBD), 58 (68%) had symmetrical ventricular enlargement, and in 47 (55%) intracranial pressure (ICP) had been increased. Thirty-five (41%) had undergone evacuation of an intracranial hematoma. Brainstem damage was seen in only 11 (13%). Analysis (χ(2) test for trends) of the relationship between these features and outcome showed that findings of DAI, raised ICP, thalamic damage, or ventricular enlargement (all p<0.005), and IBD (p=0.04) were associated with an increasingly worse outcome. Conversely, moderate or severe contusions (p=0.001) were increasingly associated with better outcomes, and evacuation of a hematoma was associated (p=0.001) with outcomes likely to be better than vegetative. We conclude that diffuse or multifocal neuropathological patterns of TBI from primary axonal injury or secondary ischemic damage are most likely to be associated with the most severely impaired outcomes after a head injury.

Genu of corpus callosum as a prognostic factor in diffuse axonal injury

OBJECT

Previous studies have shown a relationship between a patient's stage of diffuse axonal injury (DAI) and outcome. However, few studies have assessed whether a specific lesion or type of corpus callosum injury (CCI) influences outcome in patients with DAI. The authors investigated the effect of various DAIs and CCIs on outcome in patients with traumatic brain injury (TBI).

METHODS

The authors retrospectively reviewed 78 consecutive patients with DAI who were seen between May 2004 and March 2010. Outcome was evaluated using the Extended Glasgow Outcome Scale (EGOS) 1 year after TBI. Patients with single DAIs had only 1 of the 3 lesions (lobar, CC, or brainstem). Patients with dual DAIs had 2 of these lesions, and those with triple DAIs had all of these lesions. Furthermore, the authors defined single, dual, and triple CCIs by using 3 lesions (genu, body, splenium) in the same way among patients with single (CC) DAIs. Univariate and multivariate logistic regression analyses were performed to evaluate the relationships between these lesions and outcome in patients with DAI.

RESULTS

Fifty patients had single DAIs: 34 in the lobar area, 11 in the CC, and 5 in the brainstem. Twenty had dual DAIs, and 8 had triple DAIs. Of the 11 CCIs, 9 were single and 2 were dual CCIs. Among these lesions, only those in the genu were related to disability. The authors dichotomized patients into those with and without genu lesions, regardless of other injuries. Multinomial logistic regression analysis showed that a genu lesion (OR 18, 95% CI 2.2-32; p = 0.0021) and a pupillary abnormality (OR 14, 95% CI 1.6-24; p = 0.0068) were associated with disability (EGOS ≤ 6) in patients with DAI.

CONCLUSIONS

Regardless of the number of lesions, the existence of a genu lesion suggested disability 1 year after TBI in patients with DAI.

Prognostic value of magnetic resonance imaging in moderate and severe head injury: a prospective study of early MRI findings and one-year outcome

The clinical benefit of early magnetic resonance imaging (MRI) in severe and moderate head injury is unclear. We sought to explore the prognostic value of the depth of lesions depicted with early MRI, and also to describe the prevalence and impact of traumatic brainstem lesions. In a cohort of 159 consecutive patients with moderate to severe head injury (age 5-65 years and surviving the acute phase) admitted to a regional level 1 trauma center, 106 (67%) were examined with MRI within 4 weeks post-injury. Depth of lesions in MRI was categorized as: hemisphere level, central level, and brainstem injury (BSI). The outcome measure was Glasgow Outcome Scale Extended (GOSE) 12 months post-injury. Forty-six percent of patients with severe injuries and 14% of patients with moderate injuries had BSI. In severe head injury, central or brainstem lesions in MRI, together with higher Rotterdam CT score, pupillary dilation, and secondary adverse events were significantly associated with a worse outcome in age-adjusted analyses. Bilateral BSI was strongly associated with a poor outcome in severe injury, with positive and negative predictive values of 0.86 and 0.88, respectively. In moderate injury, only age was significantly associated with outcome in multivariable analyses. Limitations of the current study include lack of blinded outcome evaluations and insufficient statistical power to assess the added prognostic value of MRI when combined with clinical information. We conclude that in patients with severe head injury surviving the acute phase, depth of lesion on the MRI was associated with outcome, and in particular, bilateral brainstem injury was strongly associated with poor outcomes. In moderate head injury, surprisingly, there was no association between MRI findings and outcome when using the GOSE score as outcome measure.

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.