Investigation Of SWI Of Brain Iron Deposition In Patients With Alzheimer's Disease And Mild Cognitive Impairment

Objective:To compare the difference of brain iron deposition between Alzheimer's disease(AD) patients and mild cognitive impairment(MCI) patients and control subjects through measuring the brain iron content by applying SWI and evaluate the application value of SWI. To provide a noninvasive and valuable biological indicator for the early diagnosis of AD and MCI.Methods:24 AD patients and 22 MCI patients were collected from hospital. There are 14 men and 10 women in the AD patients and 12 men and 10 women in the MCI patients. The age range of AD patients is 64 to 83 years and average is 72.2. The age range of MCI patients is 61 to 86 years and average is 71.1.70 healthy volunteers were collected whose age is from 30 to 79.The average age is 58.There are 35 men and 35 women in the volunteers.24 volunteers whose age are from 61 to 79 were selected from them to match the group of patients. Conventional brain MR examination was performed in all people to exclude the possibility of cerebral infarction, hemorrhage, tumor, operation or trauma.SWI examination was performed and measure the phase values of red nucleus, substantia nigra, caudate nucleus head, globus pallidus, putamen, thalamus, hippocampus, temporal cortex on corrected phase SWI pictures. The control group was divided into 5 groups, each group gender was balance. To evaluate the cerebral significance of phase values difference between different ages with one-factor ANOVA. To analyse the correlation of SWI phase value of each part and age with Pearson method. To evaluate the significance of phase values difference among AD patients, MCI patients and control group with one-factor ANOVA and compare the difference between every two groups with LSD method.Results:â‘ Measured between different age groups of healthy volunteers, there were statistically differences in red nucleus, substantia nigra, caudate nucleus head, globus pallidus, putamen, hippocampus, temporal cortex SWI phase values(P<0.01).There were no differences between different ages SWI phase values of the thalamus (P=0.612>0.05).Negative correlations were measured between SWI phase values and age in red nucleus(r=-0.384, P<0.01), substantia nigra(r=-0.859, P<0.01), caudate nucleus head(r=-0.829, P<0.01), globus pallidus(r=-0.680, P<0.01), putamen(r=-0.582, P<0.01), hippocampus (r=-0.441, P<0.01), temporal cortex (r=-0.548, P<0.01).There was no correlation between the SWI phase value of thalamus and age (r=0.006, P=0.960>0.05).â‘¡There were statistically differences in red nucleus, substantia nigra. caudate nucleus head, globus pallidus, putamen, hippocampus, temporal cortex SWI phase values among AD patients, MCI patients and control group (P<0.05), but no differences in thalamus (P=0.084>0.05).â‘¢There were statistically differences in red nucleus, substantia nigra, putamen SWI phase values between AD patients and MCI patients (P<0.05). There were statistically differences in red nucleus, substantia nigra, caudate nucleus head, globus pallidus, putamen, hippocampus, temporal cortex SWI phase values between AD patients and control group(P<0.05). There were statistically differences in putamen,hippocampus, temporal cortex SWI phase values between MCI patients and control group(P<0.05).Conclusion:SWI was a simple, safe and non-invasive method and had good repeatability and can quantitatively analyse the changes of brain iron deposition. The brain iron deposition of AD patients, MCI patients and healthy volunteers could be distinguished by SWI. SWI may provide a new noninvasive dynamic monitoring method and valuable biological indicator for the early diagnosis of AD and MCI and the prevention of developing from MCI to AD.