Integrity of the Left Arcuate Fasciculus Segments Significantly Affects Language Performance in Individuals with Acute/Subacute Post-Stroke Aphasia: A Cross-Sectional Diffusion Tensor Imaging Study

Abstract

Objective: To investigate the correlation between the left arcuate fasciculus (AF) segments and acute/subacute post-stroke aphasia (PSA). Methods: Twenty-six patients underwent language assessment and MRI scanning. The integrity of the AF based on a three-segment model was evaluated using diffusion tensor imaging. All patients were classified into three groups according to the reconstruction of the left AF: completely reconstructed (group A, 8 cases), non-reconstructed (group B, 6 cases), and partially reconstructed (group C, 12 cases). The correlations and intergroup differences in language performance and diffusion indices were comprehensively estimated. Results: A correlation analyses showed that the lesion load of the language areas and diffusion indices on the left AF posterior and long segments was significantly related to some language subsets, respectively. When controlled lesion load was variable, significant correlations between diffusion indices on the posterior and long segments and comprehension, repetition, naming, and aphasia quotient were retained. Multiple comparison tests revealed intergroup differences in diffusion indices on the left AF posterior and long segments, as well as these language subsets. No significant correlation was found between the anterior segment and language performance. Conclusions: The integrity of the left AF segments, particularly the posterior segment, is crucial for the residual comprehension and repetition abilities in individuals with acute/subacute PSA, and lesion load in cortical language areas is an important factor that should be taken into account when illustrating the contributions of damage to special fiber tracts to language impairments.

Poor Spontaneous Recovery of Aphemia Accompanied by Damage to the Anterior Segment of the Left Arcuate Fasciculus: A Case Report

“…In the previous study [ 33 ], we also found the importance of the residual structure of the left AF for aphasia recovery. As well, in a recent work [ 37 ], we found that the posterior segment of the left AF might be particularly crucial for supporting the residual language abilities of patients with acute/subacute post-stroke aphasia, which was consistent with the findings of Ivanova et al [ 16 ]. Collectively, these previous findings may account for the fact that our patient underwent a good recovery of auditory comprehension, which further supports the view that an intact posterior segment is crucial for supporting residual language comprehension ability.…”

Diffusion MRI Fiber Tractography and Benzodiazepine SPECT Imaging for Assessing Neural Damage to the Language Centers in an Elderly Patient after Successful Reperfusion Therapy

“…The disruption of brain functional networks due to stroke is associated with impaired recovery from cognitive processes underlying language [ 22 ]. The left arcuate fasciculus is involved in various important neural tracts related to language function [ 23 , 24 ]. We estimated the white matter tract integrity and neuronal viability of the arcuate fasciculus using DTI fiber tracking and an assessment of the local distribution of central benzodiazepine receptor binding, respectively.…”

Predicting Language Function Post-Stroke: A Model-Based Structural Connectivity Approach

“… 5 , 8 , 9 , 11 , 12 Lesion load in language-relevant fiber tracts, such as the arcuate fasciculus , combines information on lesion size and lesion location and has been negatively associated with different language aspects after stroke, such as speech fluency and naming ability. 13 - 16 Quantifying lesion location beyond large-scale classifiers (eg, lesion load, affected cerebral lobes, and cortical and subcortical lesion location) 11 , 17 , 18 has been difficult and incorporation of such information into prediction models remained challenging.…”