title: Extended Anatomical Grading in Diffuse Axonal Injury Using MRI: Hemorrhagic Lesions in the Substantia Nigra and Mesencephalic Tegmentum Indicate Poor Long-Term Outcome.
abstract: 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).
authors.affiliation: 1 Department of Neuroscience, Neurosurgery, Uppsala University , Uppsala, Sweden .
authors.forename: Sami
authors.initials: S
authors.lastname: Abu Hamdeh
authors.affiliation: 1 Department of Neuroscience, Neurosurgery, Uppsala University , Uppsala, Sweden .
authors.forename: Niklas
authors.initials: N
authors.lastname: Marklund
authors.affiliation: 2 Department of Neuroscience, Rehabilitation Medicine, Uppsala University , Uppsala, Sweden .|3 Center of Research and Development, Uppsala University/County Council of Gävleborg , Gävle Hospital, Gävle, Sweden .
authors.forename: Marianne
authors.initials: M
authors.lastname: Lannsjö
authors.affiliation: 1 Department of Neuroscience, Neurosurgery, Uppsala University , Uppsala, Sweden .
authors.forename: Tim
authors.initials: T
authors.lastname: Howells
authors.affiliation: 4 Department of Radiology, Uppsala University , Uppsala, Sweden .
authors.forename: Raili
authors.initials: R
authors.lastname: Raininko
authors.affiliation: 4 Department of Radiology, Uppsala University , Uppsala, Sweden .
authors.forename: Johan
authors.initials: J
authors.lastname: Wikström
authors.affiliation: 1 Department of Neuroscience, Neurosurgery, Uppsala University , Uppsala, Sweden .
authors.forename: Per
authors.initials: P
authors.lastname: Enblad
mesh_terms: D000293:Adolescent; D000328:Adult; D002543:Cerebral Hemorrhage / Q000145:classification / Q000000981:diagnostic imaging* / Q000453:epidemiology; D020833:Diffuse Axonal Injury / Q000145:classification / Q000000981:diagnostic imaging* / Q000453:epidemiology; D005260:Female; D015600:Glasgow Coma Scale / Q000639:trends; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000145:classification / Q000639:trends*; D008297:Male; D008875:Middle Aged; D013378:Substantia Nigra / Q000000981:diagnostic imaging*; D013681:Tegmentum Mesencephali / Q000000981:diagnostic imaging*; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000145:classification / Q000639:trends; D016896:Treatment Outcome; D055815:Young Adult
keywords: MRI; adult brain injury; axonal injury; head trauma; susceptibility weighted imaging