VORONOI DIAGRAM AND ITS APPLICATION TO SPATIAL CALIBRATION FOR GAMMA CAMERA IMAGES

Brian D. Maisler, Hong Liu, J. E. McKisson, Yishi Li, Eric Kvam

Abstract

Gamma camera images obtained from PSPMT detectors and segmented crystal scintillators to be used for scintimammography are often distorted and blurred. Our software application is used to restore flood-field gamma camera images and map the peak positions of individual charge clusters back to the positions of the corresponding source scintillations. Since the exact position of scintillation in a crystal grain is not controllable due to the randomness of scattering, a region-to-region location map is more statistically sound than a point-to-point position map. Traditionally, an array of rectangles centered at the restored peaks of charge clusters is mapped to an array of crystal grains from which the source scintillations are emitted. We observe that the mapping is essentially a nearest neighborhood problem and innovatively introduce the Voronoi diagram to replace the rectangular array. The natural fit of the Voronoi diagram to the essence of neighborhood problem significantly improves the likelihood of correct mapping. It also makes our mapping method adaptable to apply to crystal plates in other geometric configurations. We implement the computations of Voronoi diagrams via OpenGL. As an empirical software solution, the images restored from raw flood field images illustrate high level uniformity and linearity.

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Paper Citation


in Harvard Style

D. Maisler B., Liu H., E. McKisson J., Li Y. and Kvam E. (2008). VORONOI DIAGRAM AND ITS APPLICATION TO SPATIAL CALIBRATION FOR GAMMA CAMERA IMAGES . In Proceedings of the Third International Conference on Computer Graphics Theory and Applications - Volume 1: GRAPP, (VISIGRAPP 2008) ISBN 978-989-8111-20-3, pages 68-73. DOI: 10.5220/0001096700680073


in Bibtex Style

@conference{grapp08,
author={Brian D. Maisler and Hong Liu and J. E. McKisson and Yishi Li and Eric Kvam},
title={VORONOI DIAGRAM AND ITS APPLICATION TO SPATIAL CALIBRATION FOR GAMMA CAMERA IMAGES},
booktitle={Proceedings of the Third International Conference on Computer Graphics Theory and Applications - Volume 1: GRAPP, (VISIGRAPP 2008)},
year={2008},
pages={68-73},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0001096700680073},
isbn={978-989-8111-20-3},
}


in EndNote Style

TY - CONF
JO - Proceedings of the Third International Conference on Computer Graphics Theory and Applications - Volume 1: GRAPP, (VISIGRAPP 2008)
TI - VORONOI DIAGRAM AND ITS APPLICATION TO SPATIAL CALIBRATION FOR GAMMA CAMERA IMAGES
SN - 978-989-8111-20-3
AU - D. Maisler B.
AU - Liu H.
AU - E. McKisson J.
AU - Li Y.
AU - Kvam E.
PY - 2008
SP - 68
EP - 73
DO - 10.5220/0001096700680073