A New Weighting Scheme for Fan-beam and Circle Cone-beam CT Reconstructions

TL;DR

This paper introduces a novel weighting scheme and an arc-based algorithm for fan-beam and circle cone-beam CT reconstruction, improving image quality metrics over traditional methods for short-scan trajectories.

Contribution

It presents a new weighting function and extends an arc-based fan-beam algorithm to circle cone-beam geometry, enhancing reconstruction accuracy.

Findings

Higher PSNR and SSIM compared to Parker-weighted and FDK algorithms.

Effective for super-short-scan trajectories.

Improved image quality in CT reconstructions.

Abstract

In this paper, we first present an arc based algorithm for fan-beam computed tomography (CT) reconstruction via applying Katsevich's helical CT formula to 2D fan-beam CT reconstruction. Then, we propose a new weighting function to deal with the redundant projection data. By extending the weighted arc based fan-beam algorithm to circle cone-beam geometry, we also obtain a new FDK-similar algorithm for circle cone-beam CT reconstruction. Experiments show that our methods can obtain higher PSNR and SSIM compared to the Parker-weighted conventional fan-beam algorithm and the FDK algorithm for super-short-scan trajectories.