BIAI Lab
Papers Conference paper 2021

Self-Supervised Training for Low-Dose CT Reconstruction

An IEEE ISBI paper showing that low-dose CT reconstruction can be trained without paired clean targets.

Mehmet Ozan Unal, Metin Ertas, Isa Yildirim IEEE ISBI Open paper

Summary

The paper removes the dependency on paired low-dose and normal-dose data by training directly from low-dose measurements. It adapts split-measurement style self-supervision to the CT setting and shows that clean targets are not always required to learn a useful reconstruction model.

The key move is to apply self-supervision in the projection domain, where the noise assumptions are better aligned with the requirements of the training scheme. Rather than treating CT as a generic image denoising problem, the paper uses the structure of the acquisition process itself.

Method

The approach uses low-dose sinograms as their own training targets by splitting measurements and optimizing the reconstruction pipeline without access to normal-dose references. In practice, this means the filtering stage of FBP and the parameters of a denoising network are learned together under self-supervision.

Why it matters

This conference paper establishes one of the lab’s central research directions: reconstruction methods that remain usable when paired clean data is unavailable. It is also the direct conceptual precursor to the later Proj2Proj journal paper, which develops the idea into a more complete and validated framework.

Highlights

  • Tailors self-supervised learning to CT projection data rather than generic images.
  • Establishes a practical route for labs and clinics without paired training datasets.
  • Serves as a direct precursor to the later Proj2Proj journal work.