MR-based spatiotemporal anisotropic atrophy evaluation of hippocampus in Alzheimer's disease progression by multiscale skeletal representation

Na Gao; Zhiyuan Liu; Yuesheng Deng; Hantao Chen; Chenfei Ye; Qi Yang; Ting Ma

doi:10.1002/hbm.26460

MR-based spatiotemporal anisotropic atrophy evaluation of hippocampus in Alzheimer's disease progression by multiscale skeletal representation

Hum Brain Mapp. 2023 Oct 15;44(15):5180-5197. doi: 10.1002/hbm.26460. Epub 2023 Aug 22.

Authors

Na Gao¹, Zhiyuan Liu², Yuesheng Deng¹, Hantao Chen¹, Chenfei Ye^{3

4}, Qi Yang^{5

6

7}, Ting Ma^{1

3

4

8}

Affiliations

¹ Department of Electronic & Information Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen, China.
² Department of Computer Science, University of North Carolina at, Chapel Hill, North Carolina, USA.
³ International Research Institute for Artificial Intelligence, Harbin Institute of Technology at Shenzhen, Shenzhen, China.
⁴ Peng Cheng Laboratory, Shenzhen, China.
⁵ Department of Radiology, Beijing Chaoyang Hospital, Capital Medical University, Beijing, China.
⁶ Key Lab of Medical Engineering for Cardiovascular Disease, Ministry of Education, Beijing, China.
⁷ Beijing Advanced Innovation Center for Big Data-Based Precision Medicine, Beijing, China.
⁸ Guangdong Provincial Key Laboratory of Aerospace Communication and Networking Technology, Harbin Institute of Technology (Shenzhen), Shenzhen, China.

Abstract

Increasing evidence has shown a higher sensitivity of Alzheimer's disease (AD) progression by local hippocampal atrophy rather than the whole volume. However, existing morphological methods based on subfield-volume or surface in imaging studies are not capable to describe the comprehensive process of hippocampal atrophy as sensitive as histological findings. To map histological distinctive measurements onto medical magnetic resonance (MR) images, we propose a multiscale skeletal representation (m-s-rep) to quantify focal hippocampal atrophy during AD progression in longitudinal cohorts from the Alzheimer's Disease Neuroimaging Initiative (ADNI). The m-s-rep captures large-to-small-scale hippocampal morphology by spoke interpolation over label projection on skeletal models. To enhance morphological correspondence within subjects, we align the longitudinal m-s-reps by surface-based transformations from baseline to subsequent timepoints. Cross-sectional and longitudinal measurements derived from m-s-rep are statistically analyzed to comprehensively evaluate the bilateral hippocampal atrophy. Our findings reveal that during the early AD progression, atrophy primarily affects the lateral-medial extent of the hippocampus, with a difference of 1.8 mm in lateral-medial width in 2 years preceding conversion (p < .001), and the medial head exhibits a maximum difference of 3.05%/year in local atrophy rate (p = .011) compared to controls. Moreover, progressive mild cognitive impairment (pMCI) exhibits more severe and widespread atrophy in the head and body compared to stable mild cognitive impairment (sMCI), with a maximum difference of 1.21 mm in thickness in the medial head 1 year preceding conversion (p = .012). In summary, our proposed method can quantitatively measure the hippocampal morphological changes on 3T MR images, potentially assisting the pre-diagnosis and prognosis of AD.

Keywords: Alzheimer's disease; MRI; hippocampal morphology; shape analysis; skeletal representations.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Aged
Aged, 80 and over
Alzheimer Disease* / diagnostic imaging
Alzheimer Disease* / pathology
Anisotropy
Atrophy
Datasets as Topic
Disease Progression
Female
Hippocampus* / diagnostic imaging
Hippocampus* / pathology
Humans
Magnetic Resonance Imaging
Male
Neuroimaging