Countering beam divergence effects with focused segmented scintillators for high DQE megavoltage active matrix imagers
dc.contributor.author | Liu, Langechuan | en_US |
dc.contributor.author | Antonuk, Larry E. | en_US |
dc.contributor.author | Zhao, Qihua | en_US |
dc.contributor.author | El-Mohri, Youcef | en_US |
dc.contributor.author | Jiang, Hao | en_US |
dc.date.accessioned | 2013-06-28T15:25:46Z | |
dc.date.available | 2013-06-28T15:25:46Z | |
dc.date.issued | 2012 | en_US |
dc.identifier.citation | Liu, Langechuan; Antonuk, Larry E.; Zhao, Qihua; El-Mohri, Youcef; Jiang, Hao (2012). "Countering beam divergence effects with focused segmented scintillators for high DQE megavoltage active matrix imagers." Physics in Medicine and Biology 57(16): 5343. <http://hdl.handle.net/2027.42/98594> | en_US |
dc.identifier.uri | http://stacks.iop.org/0031-9155/57/i=16/a=5343 | en_US |
dc.identifier.uri | https://hdl.handle.net/2027.42/98594 | |
dc.description.abstract | The imaging performance of active matrix flat-panel imagers designed for megavoltage imaging (MV AMFPIs) is severely constrained by relatively low x-ray detection efficiency, which leads to a detective quantum efficiency (DQE) of only ‚à º1%. Previous theoretical and empirical studies by our group have demonstrated the potential for addressing this constraint through the utilization of thick, two-dimensional, segmented scintillators with optically isolated crystals. However, this strategy is constrained by the degradation of high-frequency DQE resulting from spatial resolution loss at locations away from the central beam axis due to oblique incidence of radiation. To address this challenge, segmented scintillators constructed so that the crystals are individually focused toward the radiation source are proposed and theoretically investigated. The study was performed using Monte Carlo simulations of radiation transport to examine the modulation transfer function and DQE of focused segmented scintillators with thicknesses ranging from 5 to 60¬†mm. The results demonstrate that, independent of scintillator thickness, the introduction of focusing largely restores spatial resolution and DQE performance otherwise lost in thick, unfocused segmented scintillators. For the case of a 60¬†mm thick BGO scintillator and at a location 20¬†cm off the central beam axis, use of focusing improves DQE by up to a factor of ‚à º130 at non-zero spatial frequencies. The results also indicate relatively robust tolerance of such scintillators to positional displacements, of up to 10¬†cm in the source-to-detector direction and 2¬†cm in the lateral direction, from their optimal focusing position, which could potentially enhance practical clinical use of focused segmented scintillators in MV AMFPIs. | en_US |
dc.publisher | IOP Publishing | en_US |
dc.title | Countering beam divergence effects with focused segmented scintillators for high DQE megavoltage active matrix imagers | en_US |
dc.type | Article | en_US |
dc.subject.hlbsecondlevel | Physics | en_US |
dc.subject.hlbtoplevel | Science | en_US |
dc.description.peerreviewed | Peer Reviewed | en_US |
dc.description.bitstreamurl | http://deepblue.lib.umich.edu/bitstream/2027.42/98594/1/0031-9155_57_16_5343.pdf | |
dc.identifier.doi | 10.1088/0031-9155/57/16/5343 | en_US |
dc.identifier.source | Physics in Medicine and Biology | en_US |
dc.owningcollname | Physics, Department of |
Files in this item
Remediation of Harmful Language
The University of Michigan Library aims to describe library materials in a way that respects the people and communities who create, use, and are represented in our collections. Report harmful or offensive language in catalog records, finding aids, or elsewhere in our collections anonymously through our metadata feedback form. More information at Remediation of Harmful Language.
Accessibility
If you are unable to use this file in its current format, please select the Contact Us link and we can modify it to make it more accessible to you.