High b-value diffusion tensor imaging of the remote white matter and white matter of obstructive unilateral cerebral arterial regions

AimTo assess diffusion changes in the remote white matter and areas of white matter with cerebral artery obstruction without magnetic resonance imaging (MRI) evidence of brain parenchymal abnormalities using high b-value diffusion tensor imaging (DTI).Materials and methodsA total of 34 patients with severe unilateral stenosis (≥75%) or occlusion of the middle cerebral artery (MCA) without abnormal brain parenchymal signals at MRI underwent DTI with a b value of 2200 s/mm2 at 3 T. Fractional anisotropy (FA), apparent diffusion coefficient (ADC), axial diffusivity (eigenvalue λ1) and radial diffusivity (eigenvalue λ23) were measured at the bilateral corona radiata, anterior and posterior limbs of the internal capsule, cerebral peduncle, and pons.ResultsThe mean FA was significantly lower at the ipsilateral corona radiata and anterior and posterior limbs of the internal capsule than at the contralateral corona radiata and anterior and posterior limbs of the internal capsule (p < 0.05). The mean ADC, λ1 and λ23 were significantly higher at the ipsilateral corona radiata than at the contralateral corona radiata (p < 0.01). The mean λ23 were significantly higher at the ipsilateral anterior and posterior limb of the internal capsule than at the contralateral anterior and posterior limb of the internal capsule (p < 0.05). The mean ADC, λ1 and λ2 3were not significantly different between the ipsilateral cerebral peduncle and pons.ConclusionsHigh b-value DTI could sensitively reveal diffusion changes in white matter in regions of cerebral artery obstruction without abnormal anisotropy and diffusivity of the remote white matter of patients with severe MCA stenosis or occlusion without MRI evidence of brain parenchymal abnormalities.