Abstract:
:We investigated five different methods which can be applied to quantitatively construct functional tomograms of the lungs. The focus was on the sensitivity of functional tomograms to errors in acquired data. To quantify this sensitivity, theoretical, error-free data sets of well-known properties were artificially generated based on a 'living thorax model'. Physiological time courses and a typical distribution of errors caused by a typical Goe-MF II EIT system were used for the calculations which encompassed a range up to 50 times greater than the initial error level (4 microV(rms max)-400 microV(rms max)). Additionally, low-pass filtering and principal component analysis (PCA) were used to quantify the effect of preprocessing the raw data. The results demonstrate that all methods based on fitting the local to the global time course were superior to the common functional tomograms utilizing standard deviation or maximum and minimum detection. Ventilation distribution was best quantified by the so-called VT methods. Filling capacity--a lung tissue property--was least dependent on increasing error levels. The errors introduced by filtering are significant with respect to a quantitative analysis of ventilation distribution. A preprocessing of raw data by applying a PCA performed well on the data sets which had been constructed but were, nonetheless, realistic. This approach appears to be highly promising for application on real data which is known to be erroneous.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Hahn G,Dittmar J,Just A,Quintel M,Hellige Gdoi
10.1088/0967-3334/31/8/S06subject
Has Abstractpub_date
2010-08-01 00:00:00pages
S73-84issue
8eissn
0967-3334issn
1361-6579pii
S0967-3334(10)39084-8journal_volume
31pub_type
杂志文章abstract::Electrical impedance tomography (EIT) has shown significant promise for lung imaging. One key challenge for EIT in this application is the movement of electrodes during breathing, which introduces artefacts in reconstructed images. Various approaches have been proposed to compensate for electrode movement, but no comp...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/36/6/1119
更新日期:2015-06-01 00:00:00
abstract:OBJECTIVE:To investigate if modern seismocardiography (SCG) and ballistocardiography (BCG) are useful in the detection of hemodynamic changes occurring during simulated obstructive apneic events. METHODS:Forty-seven healthy volunteers performed a voluntary maximum Mueller maneuver (MM) for 10 s, and SCG and BCG signal...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab924b
更新日期:2020-07-09 00:00:00
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journal_title:Physiological measurement
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doi:10.1088/1361-6579/aa9047
更新日期:2017-10-31 00:00:00
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pub_type: 杂志文章
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更新日期:2018-06-27 00:00:00
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pub_type: 杂志文章
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更新日期:2020-07-02 00:00:00
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pub_type: 杂志文章
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更新日期:2016-08-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
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journal_title:Physiological measurement
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更新日期:2015-03-01 00:00:00
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pub_type: 临床试验,杂志文章
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更新日期:2018-04-26 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
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更新日期:1997-08-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/33/11/1931
更新日期:2012-11-01 00:00:00
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journal_title:Physiological measurement
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更新日期:2020-11-06 00:00:00
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pub_type: 杂志文章
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更新日期:1997-02-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
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更新日期:2020-12-11 00:00:00
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更新日期:2009-03-01 00:00:00
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pub_type: 杂志文章
doi:10.1088/0967-3334/21/4/309
更新日期:2000-11-01 00:00:00
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journal_title:Physiological measurement
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doi:10.1088/1361-6579/aba6a1
更新日期:2021-01-01 00:00:00
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更新日期:2001-08-01 00:00:00
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pub_type: 杂志文章
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pub_type: 临床试验,杂志文章
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更新日期:2011-10-01 00:00:00
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更新日期:1996-11-01 00:00:00
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pub_type: 杂志文章
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更新日期:2011-07-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/31/10/006
更新日期:2010-10-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aac7aa
更新日期:2018-06-25 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
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更新日期:2008-06-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
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更新日期:2011-06-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
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更新日期:2019-09-03 00:00:00
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pub_type: 杂志文章
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更新日期:2018-03-29 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab6ebb
更新日期:2020-03-06 00:00:00