Exceptionally fast non-linear 3D image registration using GPUs

We have developed code to test the potential of GPUs for speeding up typical 3D Medical Image registration tasks. We have used NVIDIA´s CUDA programming language because this is very close to C and hence such code is likely to have lasting value. We find registration using both affine and B-Spline based non-linear transformations can be greatly speeded up. A typical very high resolution registration using up to one B-Spline control point every two voxels can be completed in about 5 minutes using a Normalized Correlation cost function and in about eight minutes using a Normalized Mutual Information cost function.