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arXiv · 1807.03057

Deriving Neural Network Architectures using Precision Learning: Parallel-to-fan beam Conversion

Christopher Syben·Bernhard Stimpel·Jonathan Lommen·Tobias Würfl·Arnd Dörfler·Andreas Maier
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Abstract

In this paper, we derive a neural network architecture based on an analytical formulation of the parallel-to-fan beam conversion problem following the concept of precision learning. The network allows to learn the unknown operators in this conversion in a data-driven manner avoiding interpolation and potential loss of resolution. Integration of known operators results in a small number of trainable parameters that can be estimated from synthetic data only. The concept is evaluated in the context of Hybrid MRI/X-ray imaging where transformation of the parallel-beam MRI projections to fan-beam X-ray projections is required. The proposed method is compared to a traditional rebinning method. The results demonstrate that the proposed method is superior to ray-by-ray interpolation and is able to deliver sharper images using the same amount of parallel-beam input projections which is crucial for interventional applications. We believe that this approach forms a basis for further work uniting deep learning, signal processing, physics, and traditional pattern recognition.

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Christopher Syben, Bernhard Stimpel, Jonathan Lommen, Tobias Würfl, Arnd Dörfler, Andreas Maier. 2018-07-09. Deriving Neural Network Architectures using Precision Learning: Parallel-to-fan beam Conversion. https://arxiv.org/abs/1807.03057

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