What can DTI add in acute ischemic stroke patients?

Abstract

Background: Cerebrovascular stroke is one of the leading causes of death worldwide. Imaging with conventional MR techniques cannot provide reliable information as regard the integrity of the white matter tracts and therefore limiting its ability to predict the clinical outcome. While prediction of the motor outcome becomes more crucial for determining the specific rehabilitation strategies and final clinical outcomes, the purpose of this study was to assess the value of diffusion tensor MR imaging in patients with acute ischemic stroke as a prognostic imaging modality to predict the clinical outcome. Results: A significant statistical association was found between the tractography findings and the clinical score at admission (p 0.0005) and the clinical recovery after 3 months (p 0.001). Residual neurological deficits were found in patients with disrupted tracts; on the other hand, near complete clinical recovery was found in patients with non-disrupted tracts. Also, significant statistical association was found between the degree of FA reduction in the affected tracts and the clinical score at admission (p 0.001) and the clinical recovery after 3 months (p 0.01). Correlation between the FA values at the site of infarctions and the corresponding area of the brain on the contralateral side revealed significant statistical difference. Conclusion: DTI offers a potential tool for prediction of the clinical outcome of acute stroke patients as it can detect the microstructural changes in the white matter tracts affected by the ischemic lesions which cannot be detected by conventional MRI and therefore can help in determining the rehabilitation strategy

Comparison of Diffusion Tensor Imaging Metrics in Normal-Appearing White Matter to Cerebrovascular Lesions and Correlation with Cerebrovascular Disease Risk Factors and Severity

“…However, after post hoc pairwise comparisons, only subjects with an mRS of 2 (slight disability) had lower FA in NAWM than subjects with an mRS of both 0 (no symptoms) and 1 (no significant disability, despite some symptoms) (Figure 7(b)). This result is consistent with previous studies that have reported correlation between FA in NAWM or in the tracts affected by stroke lesions and mRS in stroke patients [15,[83][84][85][86]. Our results specifically suggest that structural disruptions in normal-appearing WM are different depending on the level of disability and dependence in people with CVD.…”

Magnetic Resonance Imaging and Gait Analysis Indicate Similar Outcomes Between Yucatan and Landrace Porcine Ischemic Stroke Models

“…FA, which measures the directionality of molecular displacement by diffusion, is used to infer white matter tract integrity. FA is often decreased in major white matter tracts post-stroke due to microstructural damage and loss of structural integrity resulting from local tissue damage and/or retrograde axonal degeneration ( 46 , 47 ). The asymmetrical decrease in FA may potentially be due to differences in white matter resilience, such that YC white matter is more refractory to injury.…”

Diffusion Tensor Imaging as a Prognostic Tool for Recovery in Acute and Hyperacute Stroke

“…Increases in both interhemispheric functional connectivity (FC) and ipsilesional CST-FA were significantly correlated with the greater change of Fugl–Meyer Assessment (FMA) between weeks 1 and 4 post-stroke. In line with these findings, Mahmoud and colleagues [ 37 ] studied a cohort of 60 acute ischemic stroke patients within 2 days from onset. In patients with intact WM tracts, near-complete clinical recovery was noted.…”

“…One study does did provide information regarding field strength [ 30 ]. With regards to the number of directions, three studies used 6 directions (two in 1.5 T [ 34 , 35 ] and one in 3.0 T [ 36 ]), eight studies used 12 directions (four in 1.5 T [ 37 , 38 , 39 ] and four in 3.0 T [ 40 , 41 , 42 , 43 ]), three studies used 15 directions (two in 1.5 T [ 44 , 45 ] and one in 3.0 T [ 23 ]), three studies used 16 directions (one in 1.5 T [ 46 ] and two in 3.0 T [ 24 , 47 ]), one study in 1.5 T used 20 directions [ 31 ], one study in 3.0 T used 25 directions [ 48 ], eight studies used 30 directions (two in 1.5 T [ 49 , 50 ] and six in 3.0 T [ 18 , 29 , 33 , 51 , 52 , 53 ]), three studies in 1.5 T used 32 directions [ 54 , 55 , 56 ], one study in 3.0 T used 55 directions [ 57 ], and seven studies in 3.0 T used 64 directions [ 25 , 26 , 27 , 32 , 58 , 59 , 60 ]). Six studies did not provide information regarding diffusion directions.…”

“…Of note, fiber number (FN) and fiber number ration (rFN) was also reported in some studies. Three studies used qualitative characterization of reconstructed tracts (i.e., disrupted, displaced, preserved or non-disrupted, partially disrupted, and fully-disrupted) according to which they further categorize their stroke cohorts [ 37 , 38 , 39 ].…”