Morphology And Functional Imaging Of The Human Amygdala Based On High Resolution MRI

Objective: To provide the index of linear measurement and functionevaluation for diseases related with morphological change of amygdala.Methods: Brain routine MRI,3D T1scan and DTI imaging wereemployed in a total of188people(79male and109female, age range20~75years, average age45.26±13.99) who meet the criteria and were grouped bygender and age between June2013and December2013. The volume, verticaldiameter and transverse diameter of amygdala were measured in ROI drawnmanually with the analytical software of volume of3D and standardized. TheFA value, ADC value of amygdala and the number, FA value, ADC value offiber bundle of amygdala were produced in ROI drawn by the software calledFiber Trak/Interaction Mode/Track Single ROI Fibers which belong to thePhilips in coronal view. Analysis was made in the volume, FA value, ADCvalue of amygdala and the number, FA value, ADC value of fiber bundle ofamygdala between different gender groups, laterality groups and age groupsby T test and variance analysis respectively. The correlation between verticaldiameter, transverse diameter of amygdale, the number, FA value, ADC valueof fiber bundle of amygdala and the volume of amygdala were analysed byLinear regression respectively.Results:1Bilateral volume, vertical diameter and transverse diameter ofamygdala before standardization were significantly different from gendergroups (P＜0.05), more male than female. Right side volume and bilateralvertical diameter and transverse diameter of amygdala afert standardizationwere significantly different from gender groups (P＜0.05), more male thanfemale, but left side volume of amygdala wasn’t(P＞0.05). 2Bilateral volume, vertical diameter and transverse diameter ofamygdala before or after standardization were significantly different fromlaterality groups (P＜0.05), more left than right.3Bilateral volume of amygdala before standardization was significantlydifferent from group2and group1,group3,group4,group5(P＜0.05),butafter standardization wasn’t（P＞0.05）, Vertical diameter and transversediameter of amygdala before or after standardization wasn’t significantlydifferent from age groups (P＜0.05).4The volume of amygdala was positive correlated with transversediameter, and left was more significant. The right related coefficient beforeand after standardization were r=0.299and0.297respectively(R2=0.089,0.088), the left were0.344and0.374(R2=0.118,0.14).5The volume of amygdala was positive correlated with vertical diameter.The right related coefficient before and after standardization were r=0.605and0.595respectively(R2=0.366,0.354), the left were r=0.541and0.535(R2=0.293,0.286). The R2value of the right was bigger than the left, the rightamygdala thickness had great effect on the volume.6The left number of fiber bundle of amygdala was significantly differentfrom gender groups (P=0.021), more male than female.There was no genderdifferences in the FA value, ADC value of the amygdala and the number, FAvalue, ADC value of fiber bundle of amygdala (P＞0.05).7The FA value of amygdala and the number,FA value of fiber bundle ofthe amygdala were significantly different from laterality groups (P＜0.05),more left than right. The ADC value of amygdala and ADC value of fiberbundle of amygdala had no laterality differences (P＞0.05).8There was no differences between age groups in the FA value, ADCvalue of amygdala and the number,FA value, ADC value of fiber bundle ofamygdala (P＞0.05).9The right number of fiber bundle of amygdala was positive correlatedwith volume of amygdala (r=0.151,R2=0.023). The R2value was less than0.3,which showed the volume had a little effect on the fiber bundle.Left number and bilateral FA value, ADC value of fiber bundle of amygdala hadno significant correlation with volume of amygdala.Conclusion: High resolution MRI can display the morphology clearly,probe the physiological changes, measure the volume accurately, analyse thefunction quantitatively for amygdala, and provide scientific basis for thediagnosis and differential diagnosis of diseases associated with the amygdala.