Mechanical Artifacts in Optical Projection Tomography: Classification and Automatic Calibration

TL;DR

This paper provides a comprehensive catalog of mechanical artifacts in optical projection tomography and introduces an automatic calibration method that effectively removes these artifacts, improving 3D image quality.

Contribution

It systematically catalogs mechanical artifacts in OPT and proposes an automatic calibration algorithm for artifact correction during reconstruction.

Findings

The calibration algorithm successfully removes artifacts in simulated and real data.

Experimental results show improved image quality after calibration.

The catalog aids in understanding and correcting OPT mechanical artifacts.

Abstract

Optical projection tomography (OPT) is a powerful tool for biomedical studies. It achieves 3D visualization of mesoscopic biological samples with high spatial resolution using conventional tomographic-reconstruction algorithms. However, various artifacts degrade the quality of the reconstructed images due to experimental imperfections in the OPT instruments. While many efforts have been made to characterize and correct for these artifacts, they focus on one specific type of artifacts, whereas a comprehensive catalog of all sorts of mechanical artifacts does not currently exist. In this work, we systematically document many mechanical artifacts. We rely on a 3D description of the imaging system that uses a set of angular and translational parameters. We provide a catalog of artifacts. It lists their cause, resulting effects, and existing correction methods. Then, we introduce an automatic calibration algorithm that is able to recover the unknown system parameters fed into the final 3D iterative reconstruction algorithm for a distortion-free volumetric image. Simulations with beads data and experimental results on a fluorescent textile fiber confirm that our algorithm successfully removes miscalibration artifacts in the reconstruction.