Abnormalities of the uncinate fasciculus and posterior cingulate fasciculus in mild cognitive impairment and early Alzheimer's disease: a diffusion tensor tractography study.
Mild cognitive impairment (MCI) is considered the transitional stage between normal cognition and dementia. The aim of this study was to use tractography based analysis to elucidate alterations in subjects with MCI compared with subjects with early Alzheimer's disease (AD) and controls. Seventeen subjects with early AD, 16 with MCI and 16 controls underwent magnetic resonance diffusion tensor imaging (DTI) and neuropsychological assessment. Diffusion tensor tractographies were computed and fiber-tract maps were generated using "dTV II" DTI software. We measured mean fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values along the uncinate fasciculus (UNC), posterior cingulate fasciculus (PCF) and corticospinal tract (CST). There were statistically significant differences in the FA and ADC values of the UNC and PCF between subjects with early AD and controls. Subjects with MCI exhibited significantly lower FA values on both sides of the PCF relative to controls. However, there were no significant differences between subjects with early AD and MCI for any measurement. Our results suggest that alterations in the PCF precede the onset of dementia.
Kiuchi
Kuniaki
K
Department of Psychiatry, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8522, Japan. kuniaki@naramed-u.ac.jp
Morikawa
Masayuki
M
Taoka
Toshiaki
T
Nagashima
Tomohisa
T
Yamauchi
Takahira
T
Makinodan
Manabu
M
Norimoto
Kazunobu
K
Hashimoto
Kazumichi
K
Kosaka
Jun
J
Inoue
Yuichiro
Y
Inoue
Makoto
M
Kichikawa
Kimihiko
K
Kishimoto
Toshifumi
T
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000150:complications / Q000473:pathology* / Q000523:psychology; D003072:Cognition Disorders / Q000150:complications / Q000473:pathology* / Q000523:psychology; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D042241:Early Diagnosis; D005260:Female; D006179:Gyrus Cinguli / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011712:Pyramidal Tracts / Q000473:pathology*