Regional tau deposition and subregion atrophy of medial temporal structures in early Alzheimer's disease: A combined positron emission tomography/magnetic resonance imaging study

Daichi Sone; Etsuko Imabayashi; Norihide Maikusa; Nobuyuki Okamura; Shozo Furumoto; Yukitsuka Kudo; Masayo Ogawa; Harumasa Takano; Yuma Yokoi; Masuhiro Sakata; Tadashi Tsukamoto; Koichi Kato; Hiroshi Matsuda

doi:10.1016/j.dadm.2017.07.001

Regional tau deposition and subregion atrophy of medial temporal structures in early Alzheimer's disease: A combined positron emission tomography/magnetic resonance imaging study

Alzheimers Dement (Amst). 2017 Aug 4:9:35-40. doi: 10.1016/j.dadm.2017.07.001. eCollection 2017.

Authors

Daichi Sone^{1

2}, Etsuko Imabayashi¹, Norihide Maikusa¹, Nobuyuki Okamura^{3

4}, Shozo Furumoto⁵, Yukitsuka Kudo⁴, Masayo Ogawa¹, Harumasa Takano⁶, Yuma Yokoi⁶, Masuhiro Sakata⁶, Tadashi Tsukamoto⁷, Koichi Kato¹, Hiroshi Matsuda¹

Affiliations

¹ Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Tokyo, Japan.
² Department of Neuropsychiatry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
³ Division of Pharmacology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, Sendai, Japan.
⁴ Division of Neuro-imaging, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan.
⁵ Division of Radiopharmaceutical Chemistry, Cyclotron and Radioisotope Center, Tohoku University, Sendai, Japan.
⁶ Department of Psychiatry, National Center of Neurology and Psychiatry, Tokyo, Japan.
⁷ Department of Neurology, National Center of Neurology and Psychiatry, Tokyo, Japan.

Abstract

Introduction: Molecular imaging and selective hippocampal subfield atrophy are a focus of recent Alzheimer's disease (AD) research. Here, we investigated correlations between molecular imaging and hippocampal subfields in early AD.

Methods: We investigated 18 patients with early AD and 18 healthy control subjects using ¹¹C-Pittsburgh compound-B (PIB) positron emission tomography (PET) and ¹⁸F-THK5351 PET and automatic segmentation of hippocampal subfields with high-resolution T2-weighted magnetic resonance imaging. The PET images were normalized and underwent voxelwise regression analysis with each subregion volumes using SPM12.

Results: As for ¹⁸F-THK5351 PET, the bilateral perirhinal cortex volumes were significantly associated with the ipsilateral or bilateral temporal lobar uptakes, whereas hippocampal subfields showed no correlations. ¹¹C-PIB PET showed relatively broad negative correlation with the right cornu ammonis 3 volumes.

Discussion: Regional tau deposition was correlated with extrahippocampal subregional atrophy and not with hippocampal subfields, possibly reflecting different underlying mechanisms of atrophy in early AD. Amyloid might be associated with right cornu ammonis 3 atrophy.

Keywords: Alzheimer's disease; Entorhinal cortex; Hippocampal subfield; Perirhinal cortex; Tau PET.