Pulmonary perfusion measured by means of electrical impedance tomography.


:Electrical impedance tomography (EIT) is a recent imaging technique based on electrical impedance, offering the possibility of measuring pulmonary perfusion. In the present study the influence of several pulmonary haemodynamical parameters on the EIT signal were investigated. First, the influence on the systolic wave of the EIT signal (delta Zsys) of stroke volume, large pulmonary artery distensibility (both assessed by means of MRI) and the extent of the pulmonary peripheral vascular bed in 11 emphysematous patients (reduced peripheral vascular bed) and 9 controls (normal peripheral vascular bed) was investigated. Second, the influence of hypoxic pulmonary vasoconstriction on delta Zsys was examined in 14 healthy subjects. Finally, the origin of the diastolic wave was examined in three patients with atrioventricular dissociation. Multiple regression analysis showed that delta Zsys was only dependent on the variable emphysema (p < 0.02), but not dependent on stroke volume (p < 0.3) or pulmonary artery distensibility (p > 0.9). The mean value of delta Zsys for emphysematous patients (131 +/- 32 arbitrary units (AU)) was significantly lower (p < 0.001) than in the control group (200 +/- 39). In the group of healthy subjects delta Zsys decreased significantly (p < 0.001) during hypoxia (193 +/- 38 AU) compared with rest measurements (260 +/- 62 AU). The absence of the diastolic wave in the cardiological patients suggests the influence of reverse venous blood flow on the EIT signal. It is concluded that volume changes in the small pulmonary vessels contribute significantly to the EIT signal. Moreover, the hypoxia induced decrease in delta Zsys indicates the potential of EIT for measuring pulmonary vascular responses to external stimuli.


Physiol Meas


Vonk Noordegraaf A,Kunst PW,Janse A,Marcus JT,Postmus PE,Faes TJ,de Vries PM




Has Abstract


1998-05-01 00:00:00












  • The feasibility of transoesophageal bioimpedance measurements for the detection of heart graft rejection.

    abstract::Previous studies demonstrate that it is possible to evaluate a heart graft rejection condition using a bioimpedance technique by means of an intracavitary catheter. We propose to use a less invasive technique consisting in the use of a transoesophageal catheter and two standard ECG electrodes on the thorax. The aim of...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Giovinazzo G,Ribas N,Cinca J,Rosell-Ferrer J

    更新日期:2011-07-01 00:00:00

  • Restoration of the electrocardiogram during mechanical cardiopulmonary resuscitation.

    abstract:OBJECTIVE:An artefact-free electrocardiogram (ECG) is essential during cardiac arrest to decide therapy such as defibrillation. Mechanical cardiopulmonary resuscitation (CPR) devices cause movement artefacts that alter the ECG. This study analyzes the effectiveness of mechanical CPR artefact suppression filters to rest...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Isasi I,Irusta U,Aramendi E,Idris AH,Sörnmo L

    更新日期:2020-11-06 00:00:00

  • Cardiac-related changes in lung resistivity as a function of frequency and location obtained from EITS images.

    abstract::ECG-gated electrical impedance tomographic spectroscopy (EITS) measurements of the lungs were taken on seven normal subjects in the frequency range 9.6 kHz to 614.4 kHz. The results show that in late systole the resistivity p' relative to the R-wave (i.e. p' = 1 at the R-wave) decreases consistently within the lung. I...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Nopp P,Zhao TX,Brown BH,Wang W

    更新日期:1996-11-01 00:00:00

  • Time-related heart autonomic balance characteristics in healthy subjects.

    abstract::Changes of the heart autonomic balance between morning (8-9 h) and afternoon (14-15 h) measurements were studied in 22 healthy subjects. The selection of these two daytime periods was substantiated by the established higher risk of cardiovascular incidents in the morning and the relative balance of the vegetative nerv...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Matveev M,Prokopova R,Nachev Ch

    更新日期:2003-08-01 00:00:00

  • A method for modelling and optimizing an electrical impedance tomography system.

    abstract::Electrical impedance tomography (EIT) image reconstruction is an ill-posed problem requiring maximum measurement precision. Recent EIT systems claim 60 to 80 dB precision. Achieving higher values is hard in practice since measurements must be performed at relatively high frequency, on a living subject, while using com...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Hartinger AE,Gagnon H,Guardo R

    更新日期:2006-05-01 00:00:00

  • Empirical estimators of gamma fits to tracer-dilution curves and their technical basis and practical scope.

    abstract::A gamma fit facilitates smoothing and extrapolation of distorted tracer-dilution curves in blood flow studies. Theoretically based empirical estimators were developed as simple alternatives to direct regression approaches from simulated gamma distributions with a wide range of shape asymmetry. Key curve features of pe...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Lopatatzidis A,Millard RK

    更新日期:2001-11-01 00:00:00

  • Specific heat capacity of freshly excised prostate specimens.

    abstract::The specific heat capacity of tissue is a critical parameter for thermal therapies that act over a long period of time. It is also critical for thermoacoustic signal generation. We present ex vivo measurements of specific heat capacity performed by a dual-pin probe with tight temperature control of the specimen. One 3...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Patch SK,Rao N,Kelly H,Jacobsohn K,See WA

    更新日期:2011-11-01 00:00:00

  • Multi-frequency parameter mapping of electrical impedance scanning using two kinds of circuit model.

    abstract::Electrical impedance scanning (EIS) is a kind of potential bio-impedance measurement technology, especially aiding the diagnosis of breast cancer in women. By changing the frequency of the driving signal in turn while keeping the other conditions stable, multi-frequency measurement results on the object can be obtaine...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Liu R,Dong X,Fu F,You F,Shi X,Ji Z,Wang K

    更新日期:2007-07-01 00:00:00

  • A practical approach to storage and retrieval of high-frequency physiological signals.

    abstract:OBJECTIVE:Storage of physiological waveform data for retrospective analysis presents significant challenges. Resultant data can be very large, and therefore becomes expensive to store and complicated to manage. Traditional database approaches are not appropriate for large scale storage of physiological waveforms. Our g...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Goodwin AJ,Eytan D,Greer RW,Mazwi M,Thommandram A,Goodfellow SD,Assadi A,Jegatheeswaran A,Laussen PC

    更新日期:2020-04-20 00:00:00

  • Airway resistance estimation by best fit analysis in very premature infants.

    abstract::Plethysmographic measurement of airway resistance (R(aw)) has been determined by single-point analysis, usually at 50% of maximum inspiratory flow (MIF). Computer-assisted (best fit) analysis, however, allows R(aw) to be calculated by applying a regression line to any portion of the plethysmograph pressure-flow loop. ...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Thomas M,Greenough A,Blowes R,Rafferty GF,Calvert S,Marlow N,Peacock JL,Milner AD

    更新日期:2002-05-01 00:00:00

  • Estimation of sleep stages in a healthy adult population from optical plethysmography and accelerometer signals.

    abstract:OBJECTIVE:This paper aims to report on the accuracy of estimating sleep stages using a wrist-worn device that measures movement using a 3D accelerometer and an optical pulse photoplethysmograph (PPG). APPROACH:Overnight recordings were obtained from 60 adult participants wearing these devices on their left and right w...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Beattie Z,Oyang Y,Statan A,Ghoreyshi A,Pantelopoulos A,Russell A,Heneghan C

    更新日期:2017-10-31 00:00:00

  • Characterization of the work-time relationship during cross-country ski ergometry.

    abstract::The purpose of this study was to examine the validity and reliability of estimated parameters of the work-time relationship during cross-country ski ergometry using the traditional multi-trial critical power (CP) test and a 3 min 'all-out' test (3MT). Fourteen recreationally active male participants (mean ± SD; age: 2...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Fukuda DH,Hetrick RP,Kendall KL,Smith-Ryan AE,Jackson ME,Stout JR

    更新日期:2014-01-01 00:00:00

  • An electrical impedance tomography system for gynecological application GIT with a tiny electrode array.

    abstract::The paper describes the development of an electrical impedance tomography (EIT) system for gynecologic research. The GIT (gynecological impedance tomography) system has 48 electrodes and is embedded on a small space (30 mm diameter and 20 mm height) inside of the vaginal probe. The system provides real-time (one shot ...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: V A C,Y V G,A V K,S A S,T S T

    更新日期:2012-05-01 00:00:00

  • Multiple breath washout analysis in infants: quality assessment and recommendations for improvement.

    abstract::Infant multiple breath washout (MBW) testing serves as a primary outcome in clinical studies. However, it is still unknown whether current software algorithms allow between-centre comparisons. In this study of healthy infants, we quantified MBW measurement errors and tried to improve data quality by simply changing so...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Anagnostopoulou P,Egger B,Lurà M,Usemann J,Schmidt A,Gorlanova O,Korten I,Roos M,Frey U,Latzin P

    更新日期:2016-03-01 00:00:00

  • Carotid flow rates and flow division at the bifurcation in healthy volunteers.

    abstract::In nine healthy subjects, magnetic resonance imaging was used to measure blood flow waveforms in the common (CCA), internal (ICA) and external (ECA) carotid arteries. Useful data were acquired from 14 carotid arteries in total. Flow rates were determined from regions of interest placed over the arteries in CINE-phase ...

    journal_title:Physiological measurement

    pub_type: 临床试验,杂志文章


    authors: Marshall I,Papathanasopoulou P,Wartolowska K

    更新日期:2004-06-01 00:00:00

  • Imputation of partial pressures of arterial oxygen using oximetry and its impact on sepsis diagnosis.

    abstract:OBJECTIVE:The ratio of the partial pressure of arterial oxygen to fraction of inspired oxygen is a key component of the sequential organ failure assessment score that operationally defines sepsis. But, it is calculated infrequently due to the need for the acquisition of an arterial blood gas. So, we sought to find an o...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Gadrey SM,Lau CE,Clay R,Rhodes GT,Lake DE,Moore CC,Voss JD,Moorman JR

    更新日期:2019-12-03 00:00:00

  • Snore site discrimination using statistical moments of free field snoring sounds recorded during sleep nasendoscopy.

    abstract::The non-invasive measurement of free field snoring sounds to estimate the site of snoring is an important development in the diagnosis, treatment and management of sleep-related breathing disorders. We investigated characteristics of the probability density function by testing the sensitivity of the statistical moment...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Beeton RJ,Wells I,Ebden P,Whittet HB,Clarke J

    更新日期:2007-10-01 00:00:00

  • Pilot acute study of feedback-controlled retrograde peristalsis invoked by neural gastric electrical stimulation.

    abstract::Neural gastric electrical stimulation (NGES) is a new method for invoking gastric contractions under microprocessor control. However, optimization of this technique using feedback mechanisms to minimize power consumption and maximize effectiveness has been lacking. The present pilot study proposes a prototype feedback...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Aelen P,Jurkov A,Aulanier A,Mintchev MP

    更新日期:2009-03-01 00:00:00

  • Tracking time-varying cerebral autoregulation in response to changes in respiratory PaCO2.

    abstract::Cerebral autoregulation has been studied by linear filter systems, with arterial blood pressure (ABP) as the input and cerebral blood flow velocity (CBFV-from transcranial Doppler Ultrasound) as the output. The current work extends this by using adaptive filters to investigate the dynamics of time-varying cerebral aut...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Liu J,Simpson MD,Yan J,Allen R

    更新日期:2010-10-01 00:00:00

  • Impedance analyser module for EIT and spectroscopy using undersampling.

    abstract::In this paper we present the concept, the design and the test procedure for a DSP-based high-precision and high-performance wide-band (up to 10 MHz) bioimpedance analyser module for application in EIT or bioimpedance spectroscopy. The module implements a digital concept with appropriate signal conditioning hardware fo...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Dudykevych T,Gersing E,Thiel F,Hellige G

    更新日期:2001-02-01 00:00:00

  • Development of a noncontact heart rate monitoring system for sedentary behavior based on an accelerometer attached to a chair.

    abstract::Although people spend a third of their day engaged in sedentary activities, research on heart activity during sitting is almost nonexistent because of the discomfort experienced when electrocardiogram (ECG) measurement electrodes are attached to the body. Accordingly, in this study, a system was developed to monitor h...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Lim E,Lee HK,Myoung HS,Lee KJ

    更新日期:2015-03-01 00:00:00

  • In vivo bioimpedance changes during haemorrhagic and ischaemic stroke in rats: towards 3D stroke imaging using electrical impedance tomography.

    abstract::Electrical impedance tomography (EIT) could be used as a portable non-invasive means to image the development of ischaemic stroke or haemorrhage. The purpose of this study was to examine if this was possible using time difference imaging, in the anesthetised rat using 40 spring-loaded scalp electrodes with applied con...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Dowrick T,Blochet C,Holder D

    更新日期:2016-06-01 00:00:00

  • Hemodynamic evaluation in pregnancy: limitations of impedance cardiography.

    abstract::Impedance cardiography (ICG) has been proposed to estimate the stroke volume (SV) and cardiac output (CO) in various medical indications. The aim of this study was to explore the reliability of ICG during pregnancy with respect to SV and CO measurements. Blood pressure, heart rate and thoracic impedance were monitored...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Moertl MG,Schlembach D,Papousek I,Hinghofer-Szalkay H,Weiss EM,Lang U,Lackner HK

    更新日期:2012-06-01 00:00:00

  • Test-retest reliability and minimal detectable change of repeated sit-to-stand analysis using one body fixed sensor in geriatric patients.

    abstract::A majority of geriatric patients experience difficulty in performing sit-to-stand (SiSt) transitions. A detailed assessment of SiSt ability is a prerequisite for successful rehabilitation. Body fixed sensors (BFSs) are increasingly used to assess functional performances. As to date there is no system which analyzes cl...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Schwenk M,Gogulla S,Englert S,Czempik A,Hauer K

    更新日期:2012-11-01 00:00:00

  • Permutation Lempel-Ziv complexity measure of electroencephalogram in GABAergic anaesthetics.

    abstract::Monitoring the brain state in anaesthesia is crucial for clinical doctors. In this study, we propose a novel nonlinear method, the permutation Lempel-Ziv complexity (PLZC) index, which describes the complexity in the electroencephalographic (EEG) signal to quantify the effect of GABAergic anaesthetics on brain activit...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Bai Y,Liang Z,Li X,Voss LJ,Sleigh JW

    更新日期:2015-12-01 00:00:00

  • The impact of electrode area, contact impedance and boundary shape on EIT images.

    abstract::Electrical impedance tomography (EIT) measures the conductivity distribution within an object based on the current applied and voltage measured at surface electrodes. Thus, EIT images are sensitive to electrode properties (i.e. contact impedance, electrode area and boundary shape under the electrode). While some of th...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Boyle A,Adler A

    更新日期:2011-07-01 00:00:00

  • An automated quasi-continuous capillary refill timing device.

    abstract::Capillary refill time (CRT) is a simple means of cardiovascular assessment which is widely used in clinical care. Currently, CRT is measured through manual assessment of the time taken for skin tone to return to normal colour following blanching of the skin surface. There is evidence to suggest that manually assessed ...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Blaxter LL,Morris DE,Crowe JA,Henry C,Hill S,Sharkey D,Vyas H,Hayes-Gill BR

    更新日期:2016-01-01 00:00:00

  • Effects of muscle injury severity on localized bioimpedance measurements.

    abstract::Muscle injuries in the lower limb are common among professional football players. Classification is made according to severity and is diagnosed with radiological assessment as: grade I (minor strain or minor injury), grade II (partial rupture, moderate injury) and grade III (complete rupture, severe injury). Tetrapola...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Nescolarde L,Yanguas J,Lukaski H,Alomar X,Rosell-Ferrer J,Rodas G

    更新日期:2015-01-01 00:00:00

  • Predicting clinical ischaemia during awake carotid endarterectomy: use of the SJVO2 probe as a guide to selective shunting.

    abstract::Stroke is a major cause of disability within the western world. About 20% of strokes are a consequence of atheromatous narrowing of the origin of the internal carotid artery. Carotid endarterectomy has been shown to be an effective treatment for those with symptomatic and severe stenosis, provided the risk of death an...

    journal_title:Physiological measurement

    pub_type: 临床试验,杂志文章


    authors: Crossman J,Banister K,Bythell V,Bullock R,Chambers I,Mendelow AD

    更新日期:2003-05-01 00:00:00

  • Patient-specific simulations and measurements of the magneto-hemodynamic effect in human primary vessels.

    abstract::This paper investigates the main characteristics of the magneto-hemodynamic (MHD) response for application as a biomarker of vascular blood flow. The induced surface potential changes of a volunteer exposed to a 3 T static B0 field of a magnetic resonance imaging (MRI) magnet were measured over time at multiple locati...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Kyriakou A,Neufeld E,Szczerba D,Kainz W,Luechinger R,Kozerke S,McGregor R,Kuster N

    更新日期:2012-02-01 00:00:00