Study Of The Genu And Rostrum Of Corpus Callosum By Using Diffusion Tensor Imaging Of MRI In Normal Person

Part I Study of age and sex differences of genu and rostrum of corpuscallosum by using diffusion tensor imaging in normal personPurPose: To research the differences of MRI ADC value, FA value and nervedensity of the genu and rostrum of corpus callosum in the aspects of ageand sex, and obtain the change laws with age. Materials and Method:247examinees without abnormal central nervous system signs or symptoms andwith normal head MRI were classified into ten groups according to theirages:0－1year old group(22, M12, F10),>1－3year old group(21, M11,F10),>3－6year old group(28, M14, F14),>6－12year old group(30,M13, F17),>12－18year old group(24, M14, F10),19－29year oldgroup(23, M10, F13),30－39year old group(23, M10, F13),40－49yearold group(25, M13, F12),50－59year old group(26, M13, F13),≥60year old group(25, M13, F12). Normal head MRI and DTI were performed.The images were processed with Diffusion Toolkit and TrackVis, and ROIswere selected, the fiber tracks were three-dimensionally reconstructed.The ADC value, FA value and nerve fiber number of the ROIs of genu androstrum of corpus callosum were measured separately, and then the nervedensity was calculated. Results:(1) The ADC value of genu of corpuscallosum of males has significantly descended after1years old (P<0.01),and has slowly decreased from1to18years old, however, it has remarkablyraised after18years old (P<0.01), and then has kept a relative stabletrend in the adult; The ADC value of rostrum of corpus callosum of maleshas notably reduced after1years old (P<0.01), and then has maintaineda relative stable tendency. The ADC values of genu and rostrum of corpus callosum of females have no significant difference in the age distribution.(2) All the FA value differences of genu and rostrum of corpus callosumof males and females are statistically significant with age, and theirchange laws with age mainly fit the up-relative stable-down trend.(3)All the nerve density differences of genu and rostrum of corpus callosumof males and females as age change are not significant.(4) The ADC valueof rostrum of corpus callosum of females in the>3－6year old group issignificantly higher than that of males (P<0.01); The nerve density ofgenu of corpus callosum of males is significantly higher than that offemales over40years old (P<0.01); In every age group, there are nosignificant sex differences in the ADC and FA value of genu of corpuscallosum and the FA value and nerve density of rostrum of corpus callosum.Conclusions:(1) The change laws with age of the ADC and FA value of genuand rostrum of corpus callosum can reflect the whole growing,developmental and aging process of genu and rostrum of corpus callosum.(2) The ADC value, FA value and nerve density of genu and rostrum of corpuscallosum achieved from this study can be a reference to further research. Part II Study of the fiber tracks of genu and rostrum of corpus callosumby using diffusion tensor tracking in normal adultPurPose：To three-dimensionally trace the fiber tracks of the genu androstrum of corpus callosum by using diffusion tensor tracking, and toresearch the structure, start-stop and trace of fiber tracks of the genuand rostrum of corpus callosum. Materials and Method:10examinees (M5,F5) were selected from the19－29year old group of Part I, all the DTIdata were transferred to a personal computer and were processed withDiffusion Toolkit and TrackVis. Results: The three-dimensional shape,trace and the start-stop of the fiber tracks of the genu and rostrum ofcorpus callosum were successfully reconstructed. Conclusions: Diffusiontensor tracking is useful for showing fiber tracks of the genu and rostrumof corpus callosum. This technique is a reliable way for studying thecerebral nerve tracts.