Cognitive Function In Patients With Leukoaraiosis Measured By Resting-state Functional Magnetic Resonance Imaging

Background: Leukoaraiosis is a group of clinical syndromes described by imaging and it is one of the main parts of cererbral small vessel disease.More and more studies have confirmed that leukoaraiosis is closely related to cognitive dysfunction,however,the exact mechanism is still unclearly.Objective: In this study,resting-state functional Magnetic Resonance Imaging technology was used to analyze the characteristics of resting brain function in leukoaraiosis(LA)patients,which is aimed to further explore the possible mechanisms of cognitive impairment in LA patients.Methods: A total of 80 subjects were included in this study,including 40 patients with LA group and 40 healthy subjects in control group.The related risk factors such as age,gender and years of education were collected,and all subjects also underwent the scanning of magnetic resonance imaging data and neuropsychological tests.After the data preprocessed of resting-state functional magnetic resonance imaging(rs-f MRI)was completed,fractional amplitute of low-frequency fluctuation(f ALFF)brain regions with statistical differences between the two groups were obtained through f ALFF algorithm analysis,and f ALFF brain regions with statistical differences were taken as the seed points.Through the analysis of resting brain functional connections,the brain regions with statistically significant differences between the two groups were obtained.Combined with the results of multidimensional cognitive psychology evaluation,we analyzed the significant correlation between the imaging data and behavioral performance of LA group.Results: 1.There was no significant difference in age,sex,years of education and mini-mental state examination(MMSE)between the LA group and the healthy control group(p >0.05).2.In the tests of different cognitive domains,their episodic memory ability,and information processing speed and executive function decreased in different degrees,the difference has statistics meaning(p <0.05).3.Compared with the moderate LA group,the severe LA group showed different degrees of decrease in overall cognitive function score,plot memory ability,information processing speed and executive function,and the differences were statistically significant(p <0.05).4.Compared with the healthy control group,the f ALFF in patients of LA group was significantly increased in the right precentral gyrus,precuneus,right supplementary motor area,left precentral gyrus and decreased in the left caudate.(p<0.01 after Alpha Sim adjusted).5.The bilateral parahippocampal gyrus,bilateral superior temporal gyrus,bilateral middle temporal gyrus were not as strongly correlated with the right precentral gyrus seed region in LA patients compared with the healthy control group and more strongly correlated with the right inferior frontal gyrus,right supramarginal gyrus and left posterior cingulate gyrus;The left superior temporal gyrus was not as strongly correlated with the precuneus seed region in LA patients compared with the healthy control group and more strongly correlated with the left middle frontal gyrus.The right medial frontal gyrus,right middle frontal gyrus were not as strongly correlated with the right supplementary motor area seed region in LA patients compared with the healthy control group and more strongly correlated with the left middle occipital gyrus,left middle temporal gyrus;The left superior temporal gyrus,left middle temporal gyrus,left temporal pole,right parahippocampal gyrus,right superior temporal gyrus,right anterior cingulate gyrus were not as strongly correlated with the left precentral gyrus seed region in LA patients compared with the healthy control group and there were no increased correclated brain regions.The left middle frontal gyrus,right superior temporal gyrus were more strongly correlated with the right supplementary motor area seed region in LA patients compared with the healthy control group and more strongly correlated with the right middle frontal gyrus,right medial frontal gyrus.The left frontal pole area,right superior temporal gyrus were more strongly correlated with the left caudate seed region in LA patients compared with the healthy control group and there were no decreased correclated brain regions(p <0.01 after Alpha Sim adjusted).6.The f ALFF in precuneus in patients with LA group was positively correlated with the scores of executive function cognitive domain;The functional connectivity between the right supplementary motor cortex and the right medial frontal gyrus was positively correlated with the scores of episodic memory cognitive domain and executive function cognitive domain(p <0.05).Conclusion: 1.Leukoaraiosis may cause cognitive impairment,the episodic memory,information processing speed and executive function cognitive domain were impaired in different degrees,and visual-spatial ability was relatively less impaired.2.The resting brain function in patients with leukoaraiosis has changed,which indicated that leukoaraiosis may have been an important factor lead to the impairment of brain function.3.In LA patients,the f ALFF in precuneus has a positive correlation with the executive function,which suggested that precuneus may plays an important role in executive function impairment.The functional connection strength between the right supplementary motor area and the right medial frontal gyrus was associated with the changes in the episodic memory and executive function of patients with leukoaraiosis,which suggested that the dorsolateral prefrontal cortex may have been involved in the neuropathologic process of LA related cognitive decline.