A Control Study Of Brain Magnetic Resonance Imaging And Neuropsychological Tests Of Patients In Different Periods Of Alzheimer’s Disease

Background:Alzheimer’s disease(AD)is a chronic progressive neurological degenerative disease,which is characterized by a progressive decline in cognitive function.It is the most common cause of dementia in elderly.With development of the society,Alzheimer’s disease becomes more and more prevalent.So far,there is no special treatment to effectively reverse or prevent the progress of AD,but the early intervention can slow disease progression,so early diagnosis is particularly important.According to recommendations on diagnostic guidelines for Alzheimer’s disease from the National Institute on Aging-Alzheimer’s Association workgroups,early clinical stages of Alzheimer’s disease consist of patients with mild Alzheimer’s disease dementia and those with prodromal disease.Studies in recent years show that combining multi-mode magnetic resonance imaging and neuropsychological tests is conducive to the early diagnosis of AD.Objective:For the purpose of analyzing the clinical,neuropsychological and imaging features of AD,achieving the early diagnosis and intervention of the disease,case control study was used in this research to investigate brain structural magnetic resonance imaging,magnetic resonance spectroscopy and neuropsychological scales in early(mild)and mid-advanced(moderate to severe)AD patients.Methods:Collected brain structural magnetic resonance imaging,bilateral hippocampal magnetic resonance spectroscopy,thyroid function and other laboratory indicators and neuropsychological scales of 49 cases with Alzheimer’s disease from neurology clinic of our hospital from June.2015 to December,2016.According to the clinical dementia rating scale,the patients were divided into early(mild)AD group(22 cases)and mid-advanced(moderate to severe)AD group(27 cases).Case control study was used to investigate the information about age,gender,education,medial temporal lobe atrophy,bilateral hippocampal metabolic changes and neuropsychological tests(include MMSE,MOCA and ADL)of the two groups.Results:1.The majority of 49 cases in this study were elderly patients,in which about 76%patients were over 60 years old,more women than men,the male to female ratio was roughly 1:2.Compared two groups,differences in age,the level of education and gender had no statistical significance,but the difference between two groups about years of onset was statistically significant,the average years of onset of early AD group were less than mid-advanced AD group.2.MTA grading in both groups had a rising trend with the condition worse.The difference in hippocampal atrophy between two groups was determined by using chi-square test,P value was less than 0.05,which revealed the value of MTA scale in early diagnosis and staging of AD.Relying solely on visual assessment of MTA could lead to misdiagnosis in early diagnosis of AD,and the missed diagnosis rate was 22.7%.3.Most early AD patients had shown hippocampal metabolic abnormalities,and there was abnormal MRS metabolism in most early AD patients whose structure MRI were normal,but there was still very few people shown normal hippocampal metabolism in moderate to severe AD group.Only depending on bilateral hippocampal MRS to diagnose early AD would result in misdiagnosis to some extent.Combing sMRI and MRS would be more sensitive to the early diagnosis of AD.4.The differences in MMSE,MOCA,ADL score of two groups were tested by using t test respectively,P values were less than 0.05.Compared with mid-advanced AD group,MMSE and MOCA score were higher in early AD group,but ADL score was lower,which indicated that MMSE.MOCA and ADL were meaningful to the distinguish between early and middle-late AD group.There were some early AD patients were misdiagnosed by using MMSE,MOCA or ADL test alone.Combing several neuropsychological tests could improve the sensitivity and reduce the missed diagnosis rate in the early diagnosis of AD.MOCA had a higher sensitivity for early diagnosis of AD than MMSE.MMSE score of two groups had a rising trend with the increase of the level of education.There were a downturn in MMSE and MOCA score of early AD group with the increase of MTA grading,but ADL was opposite,which showed that cognitive impairments ofearly AD patients were aggravating with the exacerbation of medial temporal lobe atrophy,and neuropsychological tests and sMRI had a certain correlation.Combing imaging and neuropsychological tests could greatly improve the accuracy of early diagnosis of AD.Conclusion:Most AD patients are the elderly,the female is more,and it is a chronic progressive disease.Combining brain structural magnetic resonance imaging and magnetic resonance spectroscopy will be better to the early diagnosis of AD.Combination of neuropsychological tests will be better to distinguish early from mid-advanced AD patients,and improve the accuracy in early diagnosis of AD.