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Objective : The goal is to evaluate longitudinally with diffusion tensor imaging (DTI) the integrity of cerebral white matter in patients with moderate and severe DAI and to correlate the DTI findings with cognitive deficits. Methods : Patients with DAI (n = 20) were scanned at three timepoints (2, 6 and 12 months) after trauma. A healthy control group (n = 20) was evaluated once with the same high-field MRI scanner. The corpus callosum (CC) and the bilateral superior longitudinal fascicles (SLFs) were assessed by deterministic tractography with ExploreDTI. A neuropschychological evaluation was also performed. Results : The CC and both SLFs demonstrated various microstructural abnormalities in between-groups comparisons. All DTI parameters demonstrated changes across time in the body of the CC, while FA (fractional anisotropy) increases were seen on both SLFs. In the splenium of the CC, progressive changes in the mean diffusivity (MD) and axial diffusivity (AD) were also observed. There was an improvement in attention and memory along time. Remarkably, DTI parameters demonstrated several correlations with the cognitive domains. Conclusions : Our findings suggest that microstructural changes in the white matter are dynamic and may be detectable by DTI throughout the first year after trauma. Likewise, patients also demonstrated improvement in some cognitive skills.

Purpose : Functional outcome prediction for patients with traumatic axonal injury (TAI) is not highly related to the MRI classifications. The aim of this study was to assess the accuracy in predicting functional outcome in patients with TAI with several MRI scoring methods and to define the most accurate method. Methods : Patients with TAI (2008-2014) confirmed on MRI <6 months after injury were included in this retrospective study. Long-term functional outcome was prospectively assessed using the Glasgow Outcome Score Extended. The Gentry classification is most used in clinical practice. This method was compared to methods that score lesion load, lesion locations, and to modified Gentry classifications. The area under the curve (AUC) was calculated for the scoring methods. Results : A total of 124 patients with TAI were included, medium follow-up 52 months. The AUC for the Gentry classification was 0.64. All tested methods were poor predictors for functional outcome, except for the 6-location score (area under the curve: 0.71). No method was significantly better than the Gentry classification. Conclusion : The Gentry classification for TAI correlates with functional outcome, but is a poor predictor for the long-term functional outcome. None of the other tested methods was significantly better.

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.

Background and Objective: Diffuse axonal injury (DAI) induces a long-term process of brain atrophy and cognitive deficits. The goal of this study was to determine whether there are correlations between brain volume loss, microhaemorrhage load (MHL) and neuropsychological performance during the first year after DAI., Methods: Twenty-four patients with moderate or severe DAI were evaluated at 2, 6 and 12 months post-injury. MHL was evaluated at 3 months, and brain volumetry was evaluated at 3, 6 and 12 months. The trail making test (TMT) was used to evaluate executive function (EF), and the Hopkins verbal learning test (HVLT) was used to evaluate episodic verbal memory (EVM) at 6 and 12 months., Results: There were significant white matter volume (WMV), subcortical grey matter volume and total brain volume (TBV) reductions during the study period (p < 0.05). MHL was correlated only with WMV reduction. EF and EVM were not correlated with MHL but were, in part, correlated with WMV and TBV reductions., Conclusions: Our findings suggest that MHL may be a predictor of WMV reduction but cannot predict EF or EVM in DAI. Brain atrophy progresses over time, but patients showed better EF and EVM in some of the tests, which could be due to neuroplasticity.

Objective: Facial emotion recognition impairment has been well documented in patients with traumatic brain injury. Studies exploring the neural substrates involved in such deficits have implicated specific grey matter structures (e.g. orbitofrontal regions), as well as diffuse white matter damage. Our study aims to clarify whether different types of injuries (i.e. focal vs. diffuse) will lead to different types of impairments on facial emotion recognition tasks, as no study has directly compared these patients., Methods: The present study examined performance and response patterns on a facial emotion recognition task in 14 participants with diffuse axonal injury (DAI), 14 with focal injury (FI) and 22 healthy controls., Results: We found that, overall, participants with FI and DAI performed more poorly than controls on the facial emotion recognition task. Further, we observed comparable emotion recognition performance in participants with FI and DAI, despite differences in the nature and distribution of their lesions. However, the rating response pattern between the patient groups was different., Conclusion: This is the first study to show that pure DAI, without gross focal lesions, can independently lead to facial emotion recognition deficits and that rating patterns differ depending on the type and location of trauma.

Objectives: We report on a patient who suffered traumatic axonal injury (TAI) of various neural tracts despite airbag deployment following mild traumatic brain injury (TBI), which was demonstrated by diffusion tensor tractography (DTT)., Case Description: A 58-year-old female patient suffered from head trauma resulting from an in-car traffic accident. At the time of head trauma, her head and face hit the deployed airbag after flexion-hyperextension-rotation injury. The patient's Glasgow Coma Scale score was 15. Since the day of head trauma, she began to feel headache and upper back pain at the mid-thoracic area. At 7 days after onset, she began to feel pain on the left hand, which spread to the right hand and leg: throbbing and cold pain without allodynia or hyperalgesia (visual analogue scale score: 5). She also felt mild weakness of all four extremities and mild memory impairment. On 4-week DTT, the corticospinal tract showed partial tearing at the subcortical white matter level in both hemispheres . The right fornical crus and right anterior cingulum were discontinued, and narrowing and partial tearing were observed in both spinothalamic tracts., Conclusions: TAI of four kinds of neural tracts was demonstrated in a patient with mild TBI despite airbag deployment, using DTT.

Background: Magnetic resonance diffusion tensor imaging (MR-DTI) is used increasingly to detect diffuse axonal injury (DAI) after traumatic brain injury (TBI)., Primary Objective: To investigate changes in the diffusion tensor imaging parameters of the corpus callosum 6 and 12 months after TBI, to optimize the timing of follow-up DTI investigations. A secondary goal was to study the relationship between DTI parameters and outcome., Research Design: Longitudinal prospective study., Methods and Procedures: MR-DTI was performed in 15 patients with suspected DAI, 6 and 12 months post-injury. Sixteen controls were also examined. Fractional anisotropy (FA) and diffusivity (trace) in the corpus callosum were analysed. The outcome measures were the extended Glasgow Outcome Scale and the Barrow Neurological Institute Screen for Higher Cerebral Functions, assessed at 6 and 12 months., Main Outcomes and Results: FA decreased and trace increased at 6 and 12 months compared to controls. Trace continued to increase even further between 6 and 12 months, while FA remained unchanged. Patients with the worst outcomes had lower FA and higher trace compared to patients with better outcomes., Conclusions: DTI parameters have not reached a stable level at 6 months after DAI, but continue to change, probably reflecting an incessant microstructural alteration of the white matter.

Objective: The aim of this study was to investigate the regional cerebral metabolism related to growth hormone deficiency (GHD) after traumatic brain injury (TBI) using F-18 fluorodeoxyglucose positron emission tomography (F-18 FDG PET) images., Methods: Twenty-three patients with diffuse axonal injury following TBI were enrolled. They underwent brain F-18 FDG PET study and an insulin tolerance test (ITT). According to the results of ITT, they were divided into two groups: patients with GHD and subjects with TBI but normal Growth Hormone (GH). Voxel-based statistical analysis was performed and the regional cerebral glucose metabolism shown on F-18 FDG PET from 10 patients with GHD was compared with those from 13 patients without GHD. Analysis was performed using SPM2 to identify regions where decreased changes in regional cerebral glucose metabolism were significantly related to GHD., Results: Compared with subjects with TBI but normal GH, patients with GHD after TBI showed decreased cerebral glucose metabolism in the Left superior frontal gyrus, Right angular gyrus, Right superior temporal gyrus, Left inferior temporal gyrus, Left anterior and middle cingulate gyrus and Right anterior and middle cingulate gyrus. (p uncorrected < 0.005)., Conclusions: The findings are suggestive of the brain region influenced by GHD. These cortical areas are involved in regulation of intellectual function, executive function and working memory.

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.

Objective: Axonal injury (AI) after traumatic brain injury (TBI) is often overlooked as an explanation for cognitive complaints when no damage is detected by computed tomography. The purpose was to assess cognition during the 12 months following a TBI and suspected traumatic axonal injury (TAI)., Methods: The sample included 17 patients younger than 65 years old, however one died. In the acute phase and at 6 and 12 months, cognition, reaction time, psychomotor performance and finger tapping speed were assessed. Working memory and work status were added at 12 months. Acute MRI findings were recorded., Results: After 1 year, all patients still showed cognitive dysfunction. A recovery had been noted at 6 months, but a cognitive decline was indicated for the majority at 12 months. The sick-listed patients had TAI located in the corpus callosum and the brainstem. They were cognitively more impaired and in more areas than the four patients who had returned to work., Conclusion: Cognitive screening can identify the long-term impact of TAI identified by conventional MRI, used as a routine clinical technique. For rehabilitation and for insurance-related matters, these injuries must be taken seriously, as a deterioration over time might occur. Further research is needed.