LOGISMOS-B is a LOGISMOS variant for cortical surface reconstruction from MRI.
LOGISMOS-B uses an atlas-based tissue classifier to generate a preliminary WM segmentation. This segmentation serves as initialization for joint reconstruction of the WM and GM surfaces by using generalized gradient vector flows (GGVF) in the LOGISMOS context. The resulting surfaces are topologically accurate and represent the globally optimal solution with respect to the cost function. Combined with the polynomial solve time of the underlying optimizers, our approach thus offers an accurate, robust and rapid means for cortical surface generation.
The GGVF strategy for graph construction provides an even coverage of the search space while avoiding self-intersections.
Evaluation in a dataset including MS patients showed that LOGISMOS-B can accurately handle challenging data including WM lesions without any manual interactions or specialized pre-processing. In contrast, the popular FreeSurfer suite generates implausible cortical surfaces for this particular dataset when used in the fully automated workflow. Cortical thickness analysis shows that unlike FreeSurfer, LOGISMOS-B accurately captures the fact that MS patients have thinner cortices then healthy subjects, both diffusely and focally in the temporal and frontal lobes. This dataset was provided by Jerry Prince (Shiee, N., Bazin, P.-L., Cuzzocreo, J. L., Ye, C., Kishore, B., Carass, A., Calabresi, P. A., Reich, D. S., Prince, J. L. and Pham, D. L. (2014), Reconstruction of the human cerebral cortex robust to white matter lesions: Method and validation. Hum. Brain Mapp., 35: 3385–3401).
A study of cortical thickness as a function of age in healthy subjects shows that LOGISMOS-B can accurately capture the known cortical thinning patterns in healthy aging. In particular, we see that the occipital lobe (visual cortex) is largely spared, whereas the frontal lobe is thinning at a rather rapid rate. The correlation of thickness with age follow similar patterns. In contrast, FreeSurfer reports a relatively homogeneous thinning rate across the whole brain. This study used data from the publicly available IXI dataset.
|Annual thinning rate||Correlation of thickness with age|
For additional details, please refer to:
I Oguz, M Sonka, “LOGISMOS-B: Layered Optimal Graph Image Segmentation of Multiple Objects and Surfaces for the Brain”, IEEE Transactions on Medical Imaging, Vol. 33(6), pp. 1-16, 2014. (link)
I Oguz, M Sonka, “Robust Cortical Thickness Measurement with LOGISMOS-B”, MICCAI, pp. 722 – 730, LNCS 8673, 2014. (link)