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arXiv · 2604.20939

Deep Reinforcement Learning for Optimizing Angle Selection and Dose Allocation in CT Reconstruction

Tianyuan Wang·Daniël M. Pelt·Felix Lucka·Tristan van Leeuwen·K. Joost Batenburg
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Abstract

Traditional X-ray computed tomography (CT) scanning strategies typically select projection angles uniformly and allocate dose equally. In practice, however, CT scans often need to be fast, radiation-efficient, and adaptive. Sparse-view tomography addresses these requirements by reducing both the number of angles and the total dose budget. Under such constraints, angle selection and dose allocation should be information-driven, with more dose assigned to informative directions. To this end, we propose a dose-aware acquisition and reconstruction framework that combines a PWLS-PnP reconstruction backbone with an RL-based strategy for adaptive angle selection, explicitly accounting for angle-dependent photon statistics. Numerical experiments show that the proposed approach improves overall reconstruction quality and enhances defect detectability compared with conventional strategies, particularly when only a small number of projections or a constrained dose budget is available.

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Tianyuan Wang, Daniël M. Pelt, Felix Lucka, Tristan van Leeuwen, K. Joost Batenburg. 2026-04-22. Deep Reinforcement Learning for Optimizing Angle Selection and Dose Allocation in CT Reconstruction. https://arxiv.org/abs/2604.20939

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