Iterative CT reconstruction with small pixel size: distance-driven forward projector versus Joseph's

Hahn K, Rassner U, Davidson HC, Sehoendube H, Stierstorfer K, Hornegger J, Noo F (2015)

Publication Status: Published

Publication Type: Conference contribution

Publication year: 2015

Journal

Proceedings of SPIE Society of Photo-optical Instrumentation Engineers (SPIE)

Publisher: International Society for Optical Engineering; 1999

Book Volume: 9412

Conference Proceedings Title: Proc. SPIE 9412, Medical Imaging 2015: Physics of Medical Imaging, 94123D (March 18, 2015)

DOI: 10.1117/12.2079286

Abstract

Over the last few years, iterative reconstruction methods have become an important research topic in x-ray CT imaging. This effort is motivated by increasing evidence that such methods may enable significant savings in terms of dose imparted to the patient. Conceptually, iterative reconstruction methods involve two important ingredients: the statistical model, which includes the forward projector, and a priori information in the image domain, which is expressed using a regularizer. Most often, the image pixel size is chosen to be equal (or close) to the detector pixel size (at field-of-view center). However, there are applications for which a smaller pixel size is desired. In this investigation, we focus on reconstruction with a pixel size that is twice smaller than the detector pixel size. Using such a small pixel size implies a large increase in computational effort when using the distance-driven method for forward projection, which models the detector size. On the other hand, the more efficient method of Joseph will create imbalances in the reconstruction of each pixel, in the sense that there will be large differences in the way each projection contributes to the pixels. The purpose of this work is to evaluate the impact of these imbalances on image quality in comparison with utilization of the distance-driven method. The evaluation involves computational effort, bias and noise metrics, and LROC analysis using human observers. The results show that Joseph's method largely remains attractive.

Authors with CRIS profile

Joachim Hornegger Lehrstuhl für Informatik 14 (Bild- und Sprachverarbeitung)

Involved external institutions

Siemens AG DE Germany (DE) University of Utah US United States (USA) (US)

How to cite

APA:

Hahn, K., Rassner, U., Davidson, H.C., Sehoendube, H., Stierstorfer, K., Hornegger, J., & Noo, F. (2015). Iterative CT reconstruction with small pixel size: distance-driven forward projector versus Joseph's. In Proc. SPIE 9412, Medical Imaging 2015: Physics of Medical Imaging, 94123D (March 18, 2015). International Society for Optical Engineering; 1999.

MLA:

Hahn, K., et al. "Iterative CT reconstruction with small pixel size: distance-driven forward projector versus Joseph's." Proceedings of the Proc. SPIE 9412, Medical Imaging 2015: Physics of Medical Imaging, 94123D (March 18, 2015) International Society for Optical Engineering; 1999, 2015.

BibTeX: Download