Abstract：
:Carotid atherosclerosis measurements for eight subjects at baseline and 14 +/- 2 days later were examined using 1.5 T and 3.0 T magnetic resonance imaging (MRI). A single observer blinded to field strength, subject and timepoint manually segmented carotid artery wall and lumen boundaries in randomized images in five measurement trials. Mean increases in the signal-to-noise ratios (SNR) for T1-weighted images acquired at 3.0 T compared to 1.5 T were 90% (scan) and 80% (rescan). Despite significantly improved SNR and contrast-to-noise ratios (CNR) for images acquired at 3.0 T, vessel wall volume (VWV) intra-observer variability was not significantly different using coefficients of variation (COV), and intraclass correlation coefficients (ICC). VWV interscan variability and consistency at both field strengths were not statistically different (1.5 T/3.0 T COV = 5.7%/7.8%, R(2) = 0.96 for 1.5 T and R(2) = 0.87 for 3.0 T). A two-way analysis of variance showed a VWV dependence on field strength but not scan timepoint. In addition, a paired t-test showed significant differences in VWV measured at 3.0 T as compared to 1.5 T. These results suggest that although images acquired at 1.5 T have lower SNR and CNR VWV, measurement variability was not significantly different from 3.0 T VWV and that VWV is field-strength dependent which may be an important consideration for longitudinal studies.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Vidal A,Bureau Y,Wade T,Spence JD,Rutt BK,Fenster A,Parraga Gdoi
10.1088/0031-9155/53/23/011subject
Has Abstractpub_date
2008-12-07 00:00:00pages
6821-35issue
23eissn
0031-9155issn
1361-6560pii
S0031-9155(08)79168-1journal_volume
53pub_type
杂志文章abstract：:Four-dimensional computed tomography (4D-CT) requires breathing information from the patient, and for this, several systems are available. Testing of these systems, under realistic conditions, requires a phantom with a moving target and an expandable outer contour. An anthropomorphic phantom was developed to simulate ...
journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/57/9/N131
更新日期：2012-05-07 00:00:00
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journal_title：Physics in medicine and biology
pub_type： 杂志文章
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journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/54/18/014
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journal_title：Physics in medicine and biology
pub_type： 评论,杂志文章,信件
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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
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journal_title：Physics in medicine and biology
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journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/43/10/021
更新日期：1998-10-01 00:00:00
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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：10.1088/1361-6560/aa8132
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journal_title：Physics in medicine and biology
pub_type： 杂志文章
doi：10.1088/0031-9155/49/16/007
更新日期：2004-08-21 00:00:00
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pub_type： 杂志文章
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更新日期：2003-12-07 00:00:00
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journal_title：Physics in medicine and biology
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journal_title：Physics in medicine and biology
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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：1993-01-01 00:00:00
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journal_title：Physics in medicine and biology
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journal_title：Physics in medicine and biology
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journal_title：Physics in medicine and biology
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journal_title：Physics in medicine and biology
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更新日期：2002-03-21 00:00:00
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journal_title：Physics in medicine and biology
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journal_title：Physics in medicine and biology
pub_type： 杂志文章
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