  As diffusion tensor imaging (DTI) gains popularity in cardiac imaging due to
its unique ability to non-invasively assess the cardiac microstructure, deep
learning-based Artificial Intelligence is becoming a crucial tool in mitigating
some of its drawbacks, such as the long scan times. As it often happens in
fast-paced research environments, a lot of emphasis has been put on showing the
capability of deep learning while often not enough time has been spent
investigating what input and architectural properties would benefit cardiac DTI
acceleration the most. In this work, we compare the effect of several input
types (magnitude images vs complex images), multiple dimensionalities (2D vs 3D
operations), and multiple input types (single slice vs multi-slice) on the
performance of a model trained to remove artefacts caused by a simultaneous
multi-slice (SMS) acquisition. Despite our initial intuition, our experiments
show that, for a fixed number of parameters, simpler 2D real-valued models
outperform their more advanced 3D or complex counterparts. The best performance
is although obtained by a real-valued model trained using both the magnitude
and phase components of the acquired data. We believe this behaviour to be due
to real-valued models making better use of the lower number of parameters, and
to 3D models not being able to exploit the spatial information because of the
low SMS acceleration factor used in our experiments.
