Cortical surface mapping using topology correction, partial flattening and 3D shape context-based non-rigid registration for use in quantifying atrophy in Alzheimer's disease.
Magnetic resonance (MR) provides a non-invasive way to investigate changes in the brain resulting from aging or neurodegenerative disorders such as Alzheimer's disease (AD). Performing accurate analysis for population studies is challenging because of the interindividual anatomical variability. A large set of tools is found to perform studies of brain anatomy and population analysis (FreeSurfer, SPM, FSL). In this paper we present a newly developed surface-based processing pipeline (MILXCTE) that allows accurate vertex-wise statistical comparisons of brain modifications, such as cortical thickness (CTE). The brain is first segmented into the three main tissues: white matter, gray matter and cerebrospinal fluid, after CTE is computed, a topology corrected mesh is generated. Partial inflation and non-rigid registration of cortical surfaces to a common space using shape context are then performed. Each of the steps was firstly validated using MR images from the OASIS database. We then applied the pipeline to a sample of individuals randomly selected from the AIBL study on AD and compared with FreeSurfer. For a population of 50 individuals we found correlation of cortical thickness in all the regions of the brain (average r=0.62 left and r=0.64 right hemispheres). We finally computed changes in atrophy in 32 AD patients and 81 healthy elderly individuals. Significant differences were found in regions known to be affected in AD. We demonstrated the validity of the method for use in clinical studies which provides an alternative to well established techniques to compare different imaging biomarkers for the study of neurodegenerative diseases.
CSIRO Preventative Health National Research Flagship, ICTC, The Australian e-Health Research Centre-BioMedIA, Herston, Australia. oscar.acosta@univ-rennes1.fr
Oscar
O
Acosta
Jurgen
J
Fripp
Vincent
V
Doré
Pierrick
P
Bourgeat
Jean-Marie
JM
Favreau
Gaël
G
Chételat
Andrea
A
Rueda
Victor L
VL
Villemagne
Cassandra
C
Szoeke
David
D
Ames
Kathryn A
KA
Ellis
Ralph N
RN
Martins
Colin L
CL
Masters
Christopher C
CC
Rowe
Erik
E
Bonner
Florence
F
Gris
Di
D
Xiao
Parnesh
P
Raniga
Vincent
V
Barra
Olivier
O
Salvado
D000328:Adult; D000368:Aged; D000465:Algorithms; D000544:Alzheimer Disease / Q000473:pathology*; D019412:Anatomy, Cross-Sectional; D001284:Atrophy; D015415:Biomarkers; D001931:Brain Mapping / Q000379:methods*; D002540:Cerebral Cortex / Q000473:pathology*; D060825:Cognitive Dysfunction / Q000473:pathology; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D019636:Neurodegenerative Diseases / Q000473:pathology; D015203:Reproducibility of Results; D012984:Software
D015415:Biomarkers