End2end-ALARA: Approaching the ALARA Law in CT Imaging with End-to-end Learning
This addresses the challenge of minimizing patient radiation exposure in medical imaging, which is an incremental improvement over existing dose modulation strategies.
The paper tackled the problem of reducing radiation dose in CT imaging while maintaining image quality, proposing an end-to-end learning framework that jointly optimizes dose modulation and reconstruction, resulting in lower dose consumption compared to conventional methods.
Computed tomography (CT) examination poses radiation injury to patient. A consensus performing CT imaging is to make the radiation dose as low as reasonably achievable, i.e. the ALARA law. In this paper, we propose an end-to-end learning framework, named End2end-ALARA, that jointly optimizes dose modulation and image reconstruction to meet the goal of ALARA in CT imaging. End2end-ALARA works by building a dose modulation module and an image reconstruction module, connecting these modules with a differentiable simulation function, and optimizing the them with a constrained hinge loss function. The objective is to minimize radiation dose subject to a prescribed image quality (IQ) index. The results show that End2end-ALARA is able to preset personalized dose levels to gain a stable IQ level across patients, which may facilitate image-based diagnosis and downstream model training. Moreover, compared to fixed-dose and conventional dose modulation strategies, End2end-ALARA consumes lower dose to reach the same IQ level. Our study sheds light on a way of realizing the ALARA law in CT imaging.