eprintid: 10052278
rev_number: 21
eprint_status: archive
userid: 608
dir: disk0/10/05/22/78
datestamp: 2018-07-16 10:52:14
lastmod: 2021-05-02 01:59:18
status_changed: 2018-07-16 12:06:39
type: proceedings_section
metadata_visibility: show
creators_name: Salvado, D
creators_name: Erlandsson, K
creators_name: Hutton, BF
title: Effects of the Collimator Magnification Factor in the Geometrical Calibration of SPECT Systems
ispublished: pub
divisions: UCL
divisions: A01
divisions: B02
divisions: C10
divisions: D17
divisions: FI6
keywords: Science & Technology, Technology, Physical Sciences, Life Sciences & Biomedicine, Engineering, Electrical & Electronic, Nuclear Science & Technology, Physics, Applied, Radiology, Nuclear Medicine & Medical Imaging, Engineering, Physics, geometrical calibration, minification, SPECT/MR, PINHOLE SPECT, RECONSTRUCTION
note: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.
abstract: In compact systems, precise measurement in the
projection space may be compromised due to minification.
The objective of this work is to investigate the impact of the
magnification factor in a model-based calibration procedure. This
has direct relevance to the geometrical calibration of the clinical
INSERT camera.
Projection data from three point sources were simulated for a
single pinhole collimator with magnification and single pinhole
and slit-slat collimators with minification, for 100 noise realizations
and 3 count levels. Model-based calibration was performed
to estimate geometric parameters and data corresponding to
a Derenzo phantom were simulated and reconstructed with
true and worst-case estimates for each collimator. Experimental
projection data were acquired with an INSERT prototype
camera and four 99mTc line sources in different locations within
the FoV. The collimator-CoR distance was varied in order to
obtain different minifications and model-based calibration was
performed.
The results from the simulations suggest that calibration is
less robust when minification is present, with higher biased
calibration parameters, which result in activity underestimation.
For experimental data, estimated parameters improved with a
higher magnification factor, in line with the simulation results.
However, some inconsistencies in the results suggest that there is
still room for improvements.
To conclude, geometric calibration of SPECT systems is more
sensitive to minification than magnification, which will impact
image quality.
date: 2016-01-01
date_type: published
publisher: IEEE
official_url: http://dx.doi.org/10.1109/NSSMIC.2016.8069589
oa_status: green
full_text_type: other
language: eng
primo: open
primo_central: open_green
verified: verified_manual
elements_id: 1535660
doi: 10.1109/NSSMIC.2016.8069589
isbn_13: 978-1-5090-1643-3
lyricists_name: Erlandsson, Kjell
lyricists_name: Hutton, Brian
lyricists_id: KERLA65
lyricists_id: BHUTT63
actors_name: Joyce, Sophia
actors_id: SJOYC12
actors_role: owner
full_text_status: public
series: IEEE Nuclear Science Symposium and Medical Imaging Conference
publication: 2016 IEEE NUCLEAR SCIENCE SYMPOSIUM, MEDICAL IMAGING CONFERENCE AND ROOM-TEMPERATURE SEMICONDUCTOR DETECTOR WORKSHOP (NSS/MIC/RTSD)
place_of_pub: Strasbourg, France
pages: 4
event_title: IEEE Nuclear Science Symposium / Medical Imaging Conference / Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD)
event_location: Strasbourg, FRANCE
event_dates: 29 October 2016 - 06 November 2016
institution: IEEE Nuclear Science Symposium / Medical Imaging Conference / Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD)
issn: 1082-3654
book_title: Proceedings of the 2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD)
citation:        Salvado, D;    Erlandsson, K;    Hutton, BF;      (2016)    Effects of the Collimator Magnification Factor in the Geometrical Calibration of SPECT Systems.                     In:  Proceedings of the 2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD).    IEEE: Strasbourg, France.       Green open access   
 
document_url: https://discovery.ucl.ac.uk/id/eprint/10052278/1/Effects%20of%20the%20Collimator%20Magnification%20Factor.pdf