Improved Longitudinal Gray Matter Atrophy Assessment Via a Combination of SIENA and a 4-Dimensional Hidden Markov Random Field Model

Michael G. Dwyer¹, Niels P. Bergsland¹, Robert Zivadinov¹

We describe a novel technique for substantially improving the reliability of longitudinal gray matter atrophy measurement through the extension of SIENAXs hidden Markov random field model from 3 dimensions to 4. We validate our approach using both simulation and real clinical data, and show a marked improvement in effect size and statistical power.