In Magnetic resonance in medicine ; h5-index 66.0
PURPOSE : To characterize the differences between histogram-based and image-based algorithms for segmentation of hyperpolarized gas lung images.
METHODS : Four previously published histogram-based segmentation algorithms (ie, linear binning, hierarchical k-means, fuzzy spatial c-means, and a Gaussian mixture model with a Markov random field prior) and an image-based convolutional neural network were used to segment 2 simulated data sets derived from a public (n = 29 subjects) and a retrospective collection (n = 51 subjects) of hyperpolarized 129Xe gas lung images transformed by common MRI artifacts (noise and nonlinear intensity distortion). The resulting ventilation-based segmentations were used to assess algorithmic performance and characterize optimization domain differences in terms of measurement bias and precision.
RESULTS : Although facilitating computational processing and providing discriminating clinically relevant measures of interest, histogram-based segmentation methods discard important contextual spatial information and are consequently less robust in terms of measurement precision in the presence of common MRI artifacts relative to the image-based convolutional neural network.
CONCLUSIONS : Direct optimization within the image domain using convolutional neural networks leverages spatial information, which mitigates problematic issues associated with histogram-based approaches and suggests a preferred future research direction. Further, the entire processing and evaluation framework, including the newly reported deep learning functionality, is available as open source through the well-known Advanced Normalization Tools ecosystem.
Tustison Nicholas J, Altes Talissa A, Qing Kun, He Mu, Miller G Wilson, Avants Brian B, Shim Yun M, Gee James C, Mugler John P, Mata Jaime F
Advanced Normalization Tools, convolutional neural network, deep learning, functional lung imaging, segmentation