Abstract:
:An algorithm is described for three-dimensional whole-body (3DWB) image reconstruction in positron emission tomography. For whole-body applications, improvements to the popular fixed-axial-acceptance-angle technique are achieved by combining axially adjacent projection data available with a long-axis data set. Time-consuming reprojection of unmeasured oblique lines of response is reduced or eliminated by axial overlap of bed positions, while pixel variance and reconstructed axial resolution are made more uniform by the overlap. Improvements in noise and resolution uniformity are accompanied by gains in reconstruction efficiency, and may be optimized against increased acquisition-time due to overlapping acquisition segments and reduced axial coverage. An 11-detector-ring overlap improves axial uniformity in coronal images of a long, uniform cylinder from 23% to 8% with uniform axial resolution. Associated with a 37% improvement in reconstruction time is a 34% reduction in axial coverage for four bed positions. A smaller degree of overlap is found to provide the best trade-off between image uniformity, total scan duration, and reconstruction time because of a proportionally greater reduction in reprojected lines of response. Using a sample optimization scheme, we find a three-ring overlap is best for a 60 cm axial field of view and a five-ring overlap for an 80 cm axial field of view.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Cutler PD,Xu Mdoi
10.1088/0031-9155/41/8/013subject
Has Abstractpub_date
1996-08-01 00:00:00pages
1453-67issue
8eissn
0031-9155issn
1361-6560journal_volume
41pub_type
杂志文章abstract::Voxel phantoms are human models based on computed tomographic or magnetic resonance images obtained from high-resolution scans of a single individual. They consist of a huge number of volume elements (voxels) and are at the moment the most precise representation of the human anatomy. The purpose of this paper is to in...
journal_title:Physics in medicine and biology
pub_type: 杂志文章,评审
doi:10.1088/0031-9155/47/1/307
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/52/5/011
更新日期:2007-03-07 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/54/10/015
更新日期:2009-05-21 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 历史文章,杂志文章
doi:10.1088/0031-9155/45/6/301
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/39/6/011
更新日期:1994-06-01 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/1361-6560/abe026
更新日期:2021-01-26 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/35/9/009
更新日期:1990-09-01 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/46/7/309
更新日期:2001-07-01 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/60/3/1199
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/39/10/003
更新日期:1994-10-01 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/49/1/002
更新日期:2004-01-07 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/55/23/004
更新日期:2010-12-07 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/1361-6560/aafcca
更新日期:2019-02-11 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/1361-6560/aba8b4
更新日期:2020-10-21 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/49/13/015
更新日期:2004-07-07 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/52/11/020
更新日期:2007-06-07 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/1361-6560/aaa307
更新日期:2018-01-16 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/55/11/002
更新日期:2010-06-07 00:00:00
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pub_type: 杂志文章
doi:10.1088/1361-6560/62/11/4300
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/45/1/302
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/61/11/4183
更新日期:2016-06-07 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/1361-6560/ab408e
更新日期:2019-09-23 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/46/8/312
更新日期:2001-08-01 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/50/22/002
更新日期:2005-11-21 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/21/6/001
更新日期:1976-11-01 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/1361-6560/aa6a99
更新日期:2017-06-07 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
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更新日期:1976-01-01 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/1361-6560/aa7a92
更新日期:2017-09-01 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/41/11/017
更新日期:1996-11-01 00:00:00