Open AccessLongitudinal assessment of magnetization transfer ratio, brain volume, and cognitive functions in diffuse axonal injury
Author(s) -
Macruz Fabiola Bezerra de Carvalho,
Feltrin Fabrício Stewan,
Zaninotto Ana,
Guirado Vinícius Monteiro de Paula,
Otaduy Maria Concepcion Garcia,
Tsunemi Miriam Harumi,
Nucci Mariana Penteado,
Rimkus Carolina,
Andrade Celi Santos,
Leite Claudia da Costa
Publication year - 2022
Publication title -
brain and behavior
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.915
H-Index - 41
ISSN - 2162-3279
DOI - 10.1002/brb3.2490
Subject(s) - diffuse axonal injury , white matter , traumatic brain injury , psychology , neuropsychology , brain size , magnetic resonance imaging , cardiology , neuroscience , medicine , nuclear medicine , cognition , radiology , psychiatry
Background Diffuse axonal injury (DAI) is a frequent mechanism of traumatic brain injury (TBI) that triggers a sequence of parenchymal changes that progresses from focal axonal shear injuries up to inflammatory response and delayed axonal disconnection. Objective The main purpose of this study is to evaluate changes in the axonal/myelinic content and the brain volume up to 12 months after TBI and to correlate these changes with neuropsychological results. Methods Patients with DAI ( n = 25) were scanned at three time points after trauma (2, 6, and 12 months), and the total brain volume (TBV), gray matter volume, and white matter volume (WMV) were calculated in each time point. The magnetization transfer ratio (MTR) for the total brain (TB MTR), gray matter (GM MTR), and white matter (WM MTR) was also quantified. In addition, Hopkins verbal learning test (HVLT), Trail Making Test (TMT), and Rey–Osterrieth Complex Figure test were performed at 6 and 12 months after the trauma. Results There was a significant reduction in the mean TBV, WMV, TB MTR, GM MTR, and WM MTR between time points 1 and 3 ( p < .05). There was also a significant difference in HVLT‐immediate, TMT‐A, and TMT‐B scores between time points 2 and 3. The MTR decline correlated more with the cognitive dysfunction than the volume reduction. Conclusion A progressive axonal/myelinic rarefaction and volume loss were characterized, especially in the white matter (WM) up to 1 year after the trauma. Despite that, specific neuropsychological tests revealed that patients’ episodic verbal memory, attention, and executive function improved during the study. The current findings may be valuable in developing long‐term TBI rehabilitation management programs.