Work

Spatial resolution properties of penalized-likelihood image reconstruction: space-invariant tomographs

Year: 1996

Type: article

Abstract: This paper examines the spatial resolution properties of penalized-likelihood image reconstruction methods by analyzing the local impulse response. The analysis shows that standard regularization penalties induce space-variant local impulse response functions, even for space-invariant tomographic systems. Paradoxically, for emission image reconstruction, the local resolution is generally poorest in high-count regions. We show that the linearized local impulse response induced by quadratic roughness penalties depends on the object only through its projections. This analysis leads naturally to a modified regularization penalty that yields reconstructed images with nearly uniform resolution. The modified penalty also provides a very practical method for choosing the regularization parameter to obtain a specified resolution in images reconstructed by penalized-likelihood methods.

Source: IEEE Transactions on Image Processing

DOI: 10.1109/83.535846

Authors: J.A. Fessler, W.L. Rogers

Institution: University of Michigan

Language: English

Topic: Medical Imaging Techniques and Applications

Subfield: Radiology, Nuclear Medicine and Imaging

Field: Medicine

Domain: Health Sciences

Open Access status: green

Funders: National Institutes of Health, National Cancer Institute

Awards: ESTIMATION STRATEGIES FOR NUCLEAR MEDICAL IMAGING, G9000225881