Abstract
A collimator is a key component of gamma cameras, which affects imaging performance significantly. Recently, pixelated scintillator arrays are widely applied in the development of highresolution gamma cameras, instead of monolithic scintillator blocks. Therefore, combining the collimator and the pixelated scintillator has been a crucial factor in achieving good imaging performance. In this study, we investigated the effects of the shape and position of a collimator hole on the image resolution of a gamma camera with a pixelated scintillator. We designed a pixel-matched collimator and a low-energy high-resolution (LEHR) collimator with hexagonal shaped holes that have the same collimator geometrical efficiency. Simulation experiments were performed with a Monte Carlo simulation package (GATE v7.0). For both types of collimator, camera sensitivity was measured for validating the collimator efficiency, and planar images were obtained to measure spatial resolution, with changing the line profile angle based on the septa direction. Camera sensitivities for both collimators were equivalent (difference = 1.76 ± 0.51%). In contrast to the case of the pixel-matched collimator, in the case of the LEHR collimator, as the angle of the line profile varied, the spatial resolution showed a difference at each profile angle. In the case when two collimator holes symmetrically matched with one scintillator pixel, the spatial resolution showed a 64.87% difference in its maximum and a position distortion of 26.06% from the original source position, according to the profile angle, compared to the other unmatched cases. These results showed that using a pixel-matched collimator in gamma camera systems employing a pixelated scintillator is essential for the exact delineation of small regions using high resolution gamma camera imaging.
| Original language | English |
|---|---|
| Pages (from-to) | 455-461 |
| Number of pages | 7 |
| Journal | Journal of the Korean Physical Society |
| Volume | 72 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - 2018 Feb 1 |
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Keywords
- Gamma camera
- Monte Carlo simulation
- Parallel hole collimator
- Pixelated scintillator
- Spatial resolution
ASJC Scopus subject areas
- Physics and Astronomy(all)
Cite this
Effects of Varying Matching Between Collimator Hole and Scintillator Pixel on Gamma Camera Image Resolution. / Kim, Minho; Bae, Jae Keon; Kim, Kyeong Min; Lee, Won Ho.
In: Journal of the Korean Physical Society, Vol. 72, No. 3, 01.02.2018, p. 455-461.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Effects of Varying Matching Between Collimator Hole and Scintillator Pixel on Gamma Camera Image Resolution
AU - Kim, Minho
AU - Bae, Jae Keon
AU - Kim, Kyeong Min
AU - Lee, Won Ho
PY - 2018/2/1
Y1 - 2018/2/1
N2 - A collimator is a key component of gamma cameras, which affects imaging performance significantly. Recently, pixelated scintillator arrays are widely applied in the development of highresolution gamma cameras, instead of monolithic scintillator blocks. Therefore, combining the collimator and the pixelated scintillator has been a crucial factor in achieving good imaging performance. In this study, we investigated the effects of the shape and position of a collimator hole on the image resolution of a gamma camera with a pixelated scintillator. We designed a pixel-matched collimator and a low-energy high-resolution (LEHR) collimator with hexagonal shaped holes that have the same collimator geometrical efficiency. Simulation experiments were performed with a Monte Carlo simulation package (GATE v7.0). For both types of collimator, camera sensitivity was measured for validating the collimator efficiency, and planar images were obtained to measure spatial resolution, with changing the line profile angle based on the septa direction. Camera sensitivities for both collimators were equivalent (difference = 1.76 ± 0.51%). In contrast to the case of the pixel-matched collimator, in the case of the LEHR collimator, as the angle of the line profile varied, the spatial resolution showed a difference at each profile angle. In the case when two collimator holes symmetrically matched with one scintillator pixel, the spatial resolution showed a 64.87% difference in its maximum and a position distortion of 26.06% from the original source position, according to the profile angle, compared to the other unmatched cases. These results showed that using a pixel-matched collimator in gamma camera systems employing a pixelated scintillator is essential for the exact delineation of small regions using high resolution gamma camera imaging.
AB - A collimator is a key component of gamma cameras, which affects imaging performance significantly. Recently, pixelated scintillator arrays are widely applied in the development of highresolution gamma cameras, instead of monolithic scintillator blocks. Therefore, combining the collimator and the pixelated scintillator has been a crucial factor in achieving good imaging performance. In this study, we investigated the effects of the shape and position of a collimator hole on the image resolution of a gamma camera with a pixelated scintillator. We designed a pixel-matched collimator and a low-energy high-resolution (LEHR) collimator with hexagonal shaped holes that have the same collimator geometrical efficiency. Simulation experiments were performed with a Monte Carlo simulation package (GATE v7.0). For both types of collimator, camera sensitivity was measured for validating the collimator efficiency, and planar images were obtained to measure spatial resolution, with changing the line profile angle based on the septa direction. Camera sensitivities for both collimators were equivalent (difference = 1.76 ± 0.51%). In contrast to the case of the pixel-matched collimator, in the case of the LEHR collimator, as the angle of the line profile varied, the spatial resolution showed a difference at each profile angle. In the case when two collimator holes symmetrically matched with one scintillator pixel, the spatial resolution showed a 64.87% difference in its maximum and a position distortion of 26.06% from the original source position, according to the profile angle, compared to the other unmatched cases. These results showed that using a pixel-matched collimator in gamma camera systems employing a pixelated scintillator is essential for the exact delineation of small regions using high resolution gamma camera imaging.
KW - Gamma camera
KW - Monte Carlo simulation
KW - Parallel hole collimator
KW - Pixelated scintillator
KW - Spatial resolution
UR - http://www.scopus.com/inward/record.url?scp=85041551469&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85041551469&partnerID=8YFLogxK
U2 - 10.3938/jkps.72.455
DO - 10.3938/jkps.72.455
M3 - Article
AN - SCOPUS:85041551469
VL - 72
SP - 455
EP - 461
JO - Journal of the Korean Physical Society
JF - Journal of the Korean Physical Society
SN - 0374-4884
IS - 3
ER -