Weobservedthecharacteristicsofwhitematterfibersandgraymatterinmultiplesclerosispatients,toidentifychangesindiffusiontensorimagingfractionalanisotropyvaluesfollowingwhitematterfiberinjury.Weanalyzedthecorrelationbetweenfractionalanisotropyvaluesandchangesinwhole-braingraymattervolume.Theparticipantsincluded20patientswithrelapsing-remittingmultiplesclerosisand20healthyvolunteersascontrols.Allsubjectsunderwentheadmagneticresonanceimaginganddiffusiontensorimaging.Ourresultsrevealedthatfractionalanisotropyvaluesdecreasedandgraymattervolumeswerereducedinthegenuandspleniumofcorpuscallosum,leftanteriorthalamicradiation,hippocampus,uncinatefasciculus,rightcorticospinaltract,bilateralcingulategyri,andinferiorlongitudinalfasciculusinmultiplesclerosispatients.Graymattervolumesweresignificantlydifferentbetweenthetwogroupsintherightfrontallobe(superiorfrontal,middlefrontal,precentral,andorbitalgyri),rightparietallobe(postcentralandinferiorparietalgyri),righttemporallobe(caudatenucleus),rightoccipitallobe(middleoccipitalgyrus),rightinsula,rightparahippocampalgyrus,andleftcingulategyrus.Thevoxelsizesofatrophicgraymatterpositivelycorrelatedwithfractionalanisotropyvaluesinwhitematterassociationfibersinthepatientgroup.Thesefindingssuggestthatwhitematterfiberbundlesareextensivelyinjuredinmultiplesclerosispatients.Themainareasofgraymatteratrophyinmultiplesclerosisarethefrontallobe,parietallobe,caudatenucleus,parahippocampalgyrus,andcingulategyrus.Graymatteratrophyisstronglyassociatedwithwhitematterinjuryinmultiplesclerosispatients,particularlywithinjurytoassociationfibers.
