Study On The Change Of Brain Gray Matter Volume In Patients With Neurosyphilis And Its Relationship With Cognitive Impairment

Objective:Based on previous studies found that patients with neurosyphilis can have significant brain atrophy,and many types of dementia have also found the characteristics of brain atrophy,Therefore,this study focuses on the cognitive impairment of patients with neurosyphilis,and aims to explore which brain areas are associated with their cognitive impairment,in order to promote everyone’s understanding of neurosyphilis cognitive impairment.Method:A total of 16 right-handed male neurosyphilis patients were enrolled in this study,aged 35-80 years,with an average age of(53.000±10.665)years and an average years of education(6.94±3.214)years.At the same time,22 right-handed healthy men who matched the neurosyphilis group’s age,sex and education years were selected as the control group.Patients with neurosyphilis have been confirmed by lumbar puncture.Each subject used Mini-Mental State Examination(MMSE)for cognitive assessment and collected 3D-T1 structure images of the whole brain.After acquiring the image,use the Dcm2nii software to convert the DICOM format file to the NIFTI format,and then use the Free Surfer software package for morphological analysis,and calculate the quantitative data of the cortical area and subcortical structure.Statistical analysis was performed using SPSS 25.0:Whether there was a difference in volume of brain region between the neurosyphilis group and the healthy control group was analyzed by two independent sample t-tests.Whether the volume changes of each brain region in the neurosyphilis group were related to cognitive impairment was analyzed by Pearson correlation analysis.Then,unary linear regression was used to confirm whether there was a causal relationship between the volume changes of related brain regions and cognitive impairment.Result:The age and education level between the neurosyphilis group and healthy control group was no significant difference(p>0.05).The difference between the MMSE(21.560±5.416)points of the neurosyphilis group and the MMSE(29.910±0.426)points of the healthy control group was obvious(p<0.001).The average volume of total cerebral cortex volume(416560.359±48159.054 mm~3),the average volume of subcortical gray matter volume(51909.000±5370.149 mm~3),the average volume of left cortical volume(208096.553±24047.141 mm~3)and the average volume of right cortical volume(208463.806±25708.558 mm~3)of the neurosyphilis group were all smaller than those of the healthy control Group(p<0.001).The bilateral cerebral hemispheres included 62 brain regions and 14 subcortical nuclei.Compared with the healthy control group,in the neurosyphilis group,except for the bilateral Cuneus cortex,bilateral Entorhinal cortex and right Pars opercularis,the volume of the other brain regions were shrunk.There are 16 brain regions that are related and causally related to neurosyphilis cognitive impairment,namely:Left Pars orbitalis(R~2=0.259,p=0.044),left Rostral middle frontal gyrus(R~2=0.452,p=0.004),right Pars orbitalis(R~2=0.275,p=0.037),right Rostral middle frontal gyrus(R~2=0.437,p=0.005),right Pars triangularis(R~2=0.292,p=0.031),right Hippocampus(R~2=0.276,p=0.037),right Putamen(R~2=0.260,p=0.044),left Fusiform gyrus(R~2=0.289,p=0.032),right Rostral anterior cingulate cortex(R~2=0.333,p=0.019),right Posterior-cingulate cortex(R~2=0.404,p=0.008),right Isthmus-cingulate cortex(R~2=0.539,p=0.001),right Postcentral gyrus(R~2=0.277,p=0.036),right Supramarginal gyrus(R~2=0.265,p=0.041),right Precuneus cortex(R~2=0.381,p=0.011),right Precentral gyrus(R~2=0.398,p=0.009)and right Lateral occipital cortex(R~2=0.258,p=0.045).Conclusion:Patients with neurosyphilis have significant brain atrophy and cause extensive cognitive impairment.Compared with the healthy control group,the total cerebral cortex volume and subcortical gray matter volume of the neurosyphilis group decreased.Analysis of 62 cortical brain regions found that 14 brain regions in patients with neurosyphilis were correlated with cognitive function.Among the 7 groups of subcortical nuclei,only the right Hippocampus and the right Putamen atrophy are related to cognitive impairment in patients with neurosyphilis.This partly overlaps with other types of dementia and has its own unique features.