Résumé
Objective To explore the imaging indexes of early diagnosis of vascular cognitive impairment (VCI).Methods Totally 30 rats were collected and divided into model group (n=20) and control group (n=10).Modified 4-VO method was used to establish the VCI rat models.Morris water maze test was used to detect learning and memory abilities of rats.T2W and DTI scanning were performed in all rats 2 weeks,1 month,3 months and 5 months after operation,respectively.ROI was used to analyze the change of hippocampal volume and FA value.Voxel-based analysis (VBA) was used to analyze the change of FA value in all brain on DTI images.Then the rats were sacrificed,HE staining and Nissl staining of brain tissue slices were performed to observe the morphological changes.Results Compared with control group,the learning and memory ability of rats in model group decreased significantly.Compared with the control group,the hippocampal volume and FA value in model group decreased significantly at 3 months and 5 months after operation,respectively (all P＜0.05).FA in many brain areas reduced 1,3,5 months after operation in model group (all P＜0.05),and the decrease regions expanded with time going.Pyramidal cells in the hippocampal showed degeneration and nuclear condensation,and cytoplasmic Nissl bodies demonstrated reduction and disappearance gradually.Conclusion Changes of rat hippocampal volume and microscopic white matter may be helpful to early diagnosis of VCI.Decrease of FA value can be used as an indicator for early diagnosis and severity evaluation of VCI.
Résumé
Objective To analyze the clinical and MRI manifestations of neurosyphilis in order to improve the recognition and di‐agnosis of the disease .Methods The MRI and clinical data of 11 patients with neurosyphilis confirmed in clinic were collected .The patients were categorized into different phenotypic types according to the clinical manifestations ,and the MRI manifestations were al‐so analyzed .Results 5 patients with parenchymal types showed cerebral atrophy .3 patients with meningovascular types showed cer‐ebral infarction .1 patient with encephalitis showed brain signal changes and meningeal enhancement .1 patient without symptom showed signal changes in brain parenchyma and mild enhancement .1 patient of myelopathic type showed signal changes of thoracic spinal cord without enhancement .Conclusion There is an overlap of the MRI findings of neurosyphilis in different clinical pheno‐types ,exhibiting no specifity .Neurosyphilis can be diagnosed when the young patient is manifested as cerebral atrophy ,infarction , MR signal intensity abnormality of cerebral parenchyma and spinal cord ,as well as meningeal enhancement .