Tiny changes in tomographic system matrices can cause large changes in reconstruction quality.
least squares
region-of-interest reconstruction
region-of-interest tomography
Journal
Physics in medicine and biology
ISSN: 1361-6560
Titre abrégé: Phys Med Biol
Pays: England
ID NLM: 0401220
Informations de publication
Date de publication:
29 04 2022
29 04 2022
Historique:
received:
16
12
2021
accepted:
08
04
2022
pubmed:
9
4
2022
medline:
4
5
2022
entrez:
8
4
2022
Statut:
epublish
Résumé
This paper studies the impact of tiny changes in region-of-interest (ROI) tomography system matrices on the variance of the reconstructed ROI. In small-scale and medium-scale examples, the variance in the reconstructed ROI was estimated for different system matrices. The results revealed a striking and counterintuitive phenomenon: a tiny change in the system matrix can dramatically affect the variance of the ROI estimate. In one of our examples, a decrease of 0.1% in one element out of hundreds of thousands of the system matrix resulted in a systematic reduction of the variance inside the ROI, and by a factor of 5 to 10 for some pixels. Our results agree with a recently proven theorem about the ability of additional measurements to reduce the variance in ROI tomography.
Identifiants
pubmed: 35395647
doi: 10.1088/1361-6560/ac65d5
doi:
Types de publication
Journal Article
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Informations de copyright
© 2022 Institute of Physics and Engineering in Medicine.