Title
Multi-atlas based segmentation of brain images: Atlas selection and its effect on accuracy.
Abstract
Quantitative research in neuroimaging often relies on anatomical segmentation of human brain MR images. Recent multi-atlas based approaches provide highly accurate structural segmentations of the brain by propagating manual delineations from multiple atlases in a database to a query subject and combining them. The atlas databases which can be used for these purposes are growing steadily. We present a framework to address the consequent problems of scale in multi-atlas segmentation. We show that selecting a custom subset of atlases for each query subject provides more accurate subcortical segmentations than those given by non-selective combination of random atlas subsets. Using a database of 275 atlases, we tested an image-based similarity criterion as well as a demographic criterion (age) in a leave-one-out cross-validation study. Using a custom ranking of the database for each subject, we combined a varying number n of atlases from the top of the ranked list. The resulting segmentations were compared with manual reference segmentations using Dice overlap. Image-based selection provided better segmentations than random subsets (mean Dice overlap 0.854 vs. 0.811 for the estimated optimal subset size, n=20). Age-based selection resulted in a similar marked improvement. We conclude that selecting atlases from large databases for atlas-based brain image segmentation improves the accuracy of the segmentations achieved. We show that image similarity is a suitable selection criterion and give results based on selecting atlases by age that demonstrate the value of meta-information for selection.
Year
DOI
Venue
2009
10.1016/j.neuroimage.2009.02.018
NeuroImage
Keywords
Field
DocType
MRI,Segmentation,Selection,Atlases,Registration
Data mining,Pattern recognition,Ranking,Computer science,Segmentation,Image segmentation,Selection criterion,Atlas (anatomy),Artificial intelligence,Neuroimaging,Dice,Atlases as Topic
Journal
Volume
Issue
ISSN
46
3
1053-8119
Citations 
PageRank 
References 
291
9.78
27
Authors
5
Search Limit
100291
Name
Order
Citations
PageRank
P Aljabar139319.19
R A Heckemann229210.47
A Hammers339918.98
J. V. Hajnal435917.44
Daniel Rueckert59338637.58