Fast predictive simple geodesic regression.

• Rapid large-scale image regression is possible on a single GPU. • A deep regression model can predict subtle longitudinal deformations. • Image regression captures correlations between deformations and clinical measures. • Algorithmic efficiency facilitates rapid analysis of the ADNI-1/2 datasets (n > 6000). Deformable image registration and regression are important tasks in medical image analysis. However, they are computationally expensive, especially when analyzing large-scale datasets that contain thousands of images. Hence, cluster computing is typically used, making the approaches dependent on such computational infrastructure. Even larger computational resources are required as study sizes increase. This limits the use of deformable image registration and regression for clinical applications and as component algorithms for other image analysis approaches. We therefore propose using a fast predictive approach to perform image registrations. In particular, we employ these fast registration predictions to approximate a simplified geodesic regression model to capture longitudinal brain changes. The resulting method is orders of magnitude faster than the standard optimization-based regression model and hence facilitates large-scale analysis on a single graphics processing unit (GPU). We evaluate our results on 3D brain magnetic resonance images (MRI) from the ADNI datasets. [ABSTRACT FROM AUTHOR]