Using machine learning to improve the image quality of low-dose photon-counting computed tomography

Date

2026

Authors

Gallagher, Kiana

Journal Title

Journal ISSN

Volume Title

Publisher

University of Victoria

Abstract

Photon-counting computed tomography (PCCT) systems use detectors that count individual X-ray photons. This makes it possible for PCCT to produce a spectrum of images based on photon energies. PCCT results in clearer images with finer anatomical detail, improved contrast between tissues, and better identification of materials. CT scans require a large number of X-ray views, collectively delivering a substantial ionizing radiation dose to patients. However, lowering the number of views decreases spatial resolution and increases image noise, making fine details harder to distinguish. This project aims to improve the image quality of low-dose PCCT scans by using a machine learning model trained on PCCT images. A U-Net was trained using ground-truth images reconstructed from 360 projections and corresponding low-dose images reconstructed from 90 projections across all energy bins. This work shows that machine learning can be used to improve the image quality of low-dose PCCT. Future work will focus on training the model on new datasets and exploring other models.

Description

Keywords

computed tomography, machine learning, medical physics, low-dose CT, photon-counting CT, Jamie Cassels Undergraduate Research Awards (JCURA)

Citation