Resting-state fMRI observation on amplitude of low-frequency fluctuation changes at specific frequencies in patients with left basal ganglia region infarction / 中国医学影像技术

ABSTRACT

Objective: To explore the changes of amplitude of low-frequency fluctuation (ALFF) in specific frequency bands (slow-4 0.027-0.073 Hz, slow-5 0.010-0.027 Hz), and to investigate the longitudinal spontaneous neuron activity changes in patients with left basal ganglia region infarction. Methods: Resting-state fMRI data of 25 patients with left basal ganglia region infarction (infarction group) and 26 normal participants (control group) were obtained. Based on two group contrasts of chronic phase and acute phase, chronic phase and normal control, the method of mixed effect analysis was used to compute the frequency differences and group differences. Then post-hoc test was used to examine the group differences at slow-4 and slow-5 frequency band separately. Results: ALFF analysis results showed significant frequency difference between the 2 frequency bands, with activated brain region of slow-4 located in subcortical region, and slow-5 located in default mode network. At slow-4 frequency band, in the contrast of chronic phase and acute phase, patients in chronic phase showed increased ALFF value at bilateral superior parietal lobule, precuneus, occipital cortex and contralateral temporal cortex, while decreased ALFF value at bilateral cingulum gyrus and supplementary motor area. In the contrast of chronic phase and normal control, ALFF values of chronic phase patients decreased at contralateral posterior cingulate (PCC) and ipsilateral precentral gyrus, whereas increased at contralateral lateral frontal lobule and frontal pole. There was no significant difference of two group contrasts at slow-5 frequency band. Conclusion: Slow-4 frequency band is sensitive to show spontaneous brain activity in patients with left basal ganglia region infarction, and the cortical function is reconstructed during motor recovery.