Structural integrity of the contralesional hemisphere predicts cognitive impairment in ischemic stroke at three months.
After stroke, white matter integrity can be affected both locally and distally to the primary lesion location. It has been shown that tract disruption in mirror's regions of the contralateral hemisphere is associated with degree of functional impairment. Fourteen patients suffering right hemispheric focal stroke (S) and eighteen healthy controls (HC) underwent Diffusion Weighted Imaging (DWI) and neuropsychological assessment. The stroke patient group was divided into poor (SP; n = 8) and good (SG; n = 6) cognitive recovery groups according to their cognitive improvement from the acute phase (72 hours after stroke) to the subacute phase (3 months post-stroke). Whole-brain DWI data analysis was performed by computing Diffusion Tensor Imaging (DTI) followed by Tract Based Spatial Statistics (TBSS). Assessment of effects was obtained computing the correlation of the projections on TBSS skeleton of Fractional Anisotropy (FA) and Radial Diffusivity (RD) with cognitive test results. Significant decrease of FA was found only in right brain anatomical areas for the S group when compared to the HC group. Analyzed separately, stroke patients with poor cognitive recovery showed additional significant FA decrease in several left hemisphere regions; whereas SG patients showed significant decrease only in the left genu of corpus callosum when compared to the HC. For the SG group, whole brain analysis revealed significant correlation between the performance in the Semantic Fluency test and the FA in the right hemisphere as well as between the performance in the Grooved Pegboard Test (GPT) and the Trail Making Test-part A and the FA in the left hemisphere. For the SP group, correlation analysis revealed significant correlation between the performance in the GPT and the FA in the right hemisphere.
Group of Computational Intelligence, University of the Basque Country UPV/EHU, San Sebastian, Spain.
Rosalia
R
Dacosta-Aguayo
Group of Computational Intelligence, University of the Basque Country UPV/EHU, San Sebastian, Spain.
Manuel
M
Graña
Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Barcelona, Spain ; Institute for Brain, Cognition and Behaviour (IR3C), Barcelona, Spain.
Marina
M
Fernández-Andújar
Department of Neurosciences, Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona, Barcelona, Spain.
Elena
E
López-Cancio
Department of Neurosciences, Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona, Barcelona, Spain.
Cynthia
C
Cáceres
Diagnostic Center for Image, Clinic Hospital, Barcelona, Spain ; Imatge Platform of IDIBAPS, Barcelona, Spain.
Núria
N
Bargalló
Department of Methodology of Behavioral Sciences, University of Barcelona, Spain.
Maite
M
Barrios
Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Barcelona, Spain ; Institute for Brain, Cognition and Behaviour (IR3C), Barcelona, Spain.
Immaculada
I
Clemente
Primary Healthcare Research Support Unit Metropolitana Nord, Institut Universitari d'Investigació en Atenció Primària (-IDIAP) Jordi Gol, Santa Coloma de Gramenet, Spain.
Pere Toran
PT
Monserrat
Primary Healthcare Research Support Unit Metropolitana Nord, Institut Universitari d'Investigació en Atenció Primària (-IDIAP) Jordi Gol, Santa Coloma de Gramenet, Spain.
Maite Alzamora
MA
Sas
Department of Neurosciences, Hospital Germans Trias i Pujol, Universitat Autònoma de Barcelona, Barcelona, Spain.
Antoni
A
Dávalos
MRC Cognition and Brain Sciences Unit, Cambridge, England.
Tibor
T
Auer
Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Barcelona, Spain ; Institute for Brain, Cognition and Behaviour (IR3C), Barcelona, Spain.
Maria
M
Mataró
D000368:Aged; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000473:pathology*; D003072:Cognition Disorders / Q000175:diagnosis* / Q000209:etiology* / Q000503:physiopathology; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors; D020521:Stroke / Q000150:complications* / Q000473:pathology*; D013997:Time Factors