University of Massachusetts Medical School Faculty Publications


Impact of Mismatched Detector-Blur Models on Ga SPECT Tumor Detection

UMMS Affiliation

Department of Radiology

Publication Date


Document Type

Conference Proceeding


Analytical, Diagnostic and Therapeutic Techniques and Equipment | Bioimaging and Biomedical Optics | Biological and Chemical Physics | Nuclear | Nuclear Engineering | Radiology


The quality of SPECT images suffers from the effects of photon attenuation and scatter, and from distance-dependent collimator blur, and many researchers have shown the benefit of compensating for these degradations in the inverse problem. For this work, we examined how using an incorrect collimator-blur model affects the detection and localization of (67)Ga-avid lymphomas in simulated chest scans. In particular, we considered whether blur-overcompensation can enhance reconstructed images for purposes of localizing tumors. Variations in the correct linear model for medium-energy, parallel-hole collimators were compared by means of LROC studies with human and localizing model observers. Imaging data consisted of Simind projections of the MCAT phantom, and RBI reconstructions were performed. Our results indicate that tumor-detection performance is not improved by using a mismatched RC model. Reconstruction with increased RC requires more iterations, which leads to longer noise correlations. Our results also suggest a substantial observer insensitivity to the accuracy of the RC model.


Image reconstruction, Single photon emission computed tomography, Attenuation, Electromagnetic scattering, Particle scattering, Optical collimators, Degradation, Inverse problems, Neoplasms, Humans

DOI of Published Version



Gifford HC, King MA. Impact of Mismatched Detector-Blur Models on Ga SPECT Tumor Detection. IEEE Nucl Sci Symp Conf Rec (1997). 2007;6:4226-4229. doi: 10.1109/NSSMIC.2007.4437050. PMID: 19890463; PMCID: PMC2772205. Link to article on publisher's site

Related Resources

Link to Article in PubMed

Journal/Book/Conference Title

IEEE Nuclear Science Symposium conference record. Nuclear Science Symposium

PubMed ID