Kejal Kantarci1, Ramesh T. Avula1, Ali R. Samikoglu1, Maria M. Shiung1, Scott A. Przybelski2, Stephen D. Weigand2, Heidi A. Ward1, Prashanthi Vemuri1, David S. Knopman3, Bradley F. Boeve3, Ronald C. Petersen3, Clifford R. Jack, Jr. 1
1Department of Radiology, Mayo Clinic, Rochester, MN, USA; 2Division of Biostatistics, Mayo Clinic, Rochester, MN, USA; 3Department of Neurology, Mayo Clinic, Rochester, MN, USA
Patients with the amnestic subtype of mild cognitive impairment (aMCI) have an increased risk of Alzheimers disease (AD). Our objective was to determine the characteristic DTI profiles of the aMCI and non-amnestic MCI (naMCI) subtypes. Hippocampal ADC was increased in patients with aMCI, and posterior cingulum tract FA was decreased in patients with aMCI and naMCI compared to cognitively normal subjects. Elevated hippocampal ADC most likely represents hippocampal neurodegeneration and a high frequency of early AD pathology in aMCI patients. Normal hippocampal ADC in the naMCI subtype suggest that other pathologies may be responsible for cognitive impairment some naMCI patients.