Abstract:
PURPOSE:To reduce the influence of tidal volume on fractional ventilation (FV) derived by Fourier decomposition (FD). METHODS:Twelve volunteers were examined on a 1.5 Tesla scanner. Spoiled gradient echo imaging of coronal and sagittal slices of the lung were performed. The tidal volume variations between different acquisitions were studied by reproducibility and repeatability measurements. To adjust the FV derived by FD for tidal volume differences between the measurements, during all acquisitions, the lung volume changes were measured by a spirometer and used to calculate a global FV parameter. As an alternative, using the FD data, the lung area changes were calculated and used for the adjustment. RESULTS:Reproducibility analysis of unadjusted coronal FV showed a determination coefficient of R2 = 71% and an intraclass correlation coefficient of ICC = 93%. Differences in the measurements could be ascribed to different tidal volumes. Area adjusted values exhibited an increased R2 of 84% and a higher ICC of 97%. For the coronal middle slice/sagittal slices in free breathing, the inter-volunteer coefficient of variation was reduced from 0.23/0.28 (unadjusted) to 0.16/0.20 (spirometer) or 0.12/0.13 (area). CONCLUSION:The calculation of lung area changes is sufficient to increase the reproducibility of FV in a volunteer cohort avoiding the need for an MRI compatible spirometer. Magn Reson Med 76:1542-1550, 2016. © 2015 International Society for Magnetic Resonance in Medicine.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Voskrebenzev A,Gutberlet M,Becker L,Wacker F,Vogel-Claussen Jdoi
10.1002/mrm.26047subject
Has Abstractpub_date
2016-11-01 00:00:00pages
1542-1550issue
5eissn
0740-3194issn
1522-2594journal_volume
76pub_type
杂志文章abstract::Although promising for visualizing the structure of ordered tissues, MR diffusion tensor imaging (DTI) has been hampered by long acquisition time and low spatial resolution associated with its inherently low signal-to-noise ratio (SNR). Moreover, the uncertainty in the DTI measurements has a direct impact on the accur...
journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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abstract::Functional MRI (fMRI) was used to assess proprioceptive-associated cervical cord activity in 24 relapsing multiple sclerosis (MS) patients and 10 controls. Cord and brain conventional and diffusion tensor (DT) MRI were also acquired. fMRI was performed using a block design during a proprioceptive stimulation consistin...
journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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更新日期:2004-05-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.22029
更新日期:2009-09-01 00:00:00
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更新日期:2008-07-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2018-08-01 00:00:00
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更新日期:1997-03-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2018-03-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2017-11-01 00:00:00
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更新日期:2005-11-01 00:00:00
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更新日期:2019-02-01 00:00:00