Validation of a finite-element solution for electrical impedance tomography in an anisotropic medium.


:Electrical impedance tomography is an imaging method, with which volumetric images of conductivity are produced by injecting electrical current and measuring boundary voltages. It has the potential to become a portable non-invasive medical imaging technique. Until now, implementations have neglected anisotropy even though human tissues such as bone, muscle and brain white matter are markedly anisotropic. We present a numerical solution using the finite-element method that has been modified for modelling anisotropic conductive media. It was validated in an anisotropic domain against an analytical solution in an isotropic medium after the isotropic domain was diffeomorphically transformed into an anisotropic one. Convergence of the finite element to the analytical solution was verified by showing that the finite-element error norm decreased linearly related to the finite-element size, as the mesh density increased, for the simplified case of Laplace's equation in a cubic domain with a Dirichlet boundary condition.


Physiol Meas


Abascal JF,Arridge SR,Lionheart WR,Bayford RH,Holder DS




Has Abstract


2007-07-01 00:00:00














  • An instrumented timed up and go: the added value of an accelerometer for identifying fall risk in idiopathic fallers.

    abstract::The Timed Up and Go (TUG) test is a widely used measure of mobility and fall risk among older adults that is typically scored using a stopwatch. We tested the hypothesis that a body-fixed accelerometer can enhance the ability of the TUG to identify community-living older adults with a relatively high fall risk of unkn...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Weiss A,Herman T,Plotnik M,Brozgol M,Giladi N,Hausdorff JM

    更新日期:2011-12-01 00:00:00

  • Electrical biopsy of irradiated intestinal tissue with a simple electrical impedance spectroscopy system for radiation enteropathy in rats--a pilot study.

    abstract::Electrical impedance is one of the most often used parameters for characterizing material properties, especially in biomedical applications. Electrical impedance spectroscopy (EIS), used for revealing both resistive and capacitive characteristics, is good for use in tissue characterization. In this study, a portable a...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Huang YJ,Huang EY,Lu YY,Chen CY,Cheng KS

    更新日期:2011-09-01 00:00:00

  • Assessing the validity and reliability and determining cut-points of the Actiwatch 2 in measuring physical activity.

    abstract:OBJECTIVE:The Actiwatch 2 (AW2) is a wrist-worn accelerometer typically used to measure sleep. Although it can measure physical activity, there is limited evidence supporting its validity. We assessed the validity and reliability of the AW2 to measure sedentary behavior and physical activity (light, moderate, vigorous ...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Kemp C,Pienaar PR,Henst RHP,Roden LC,Kolbe-Alexander TL,Rae DE

    更新日期:2020-09-04 00:00:00

  • Estimating carotid pulse and breathing rate from near-infrared video of the neck.

    abstract:OBJECTIVE:Non-contact physiological measurement is a growing research area that allows capturing vital signs such as heart rate (HR) and breathing rate (BR) comfortably and unobtrusively with remote devices. However, most of the approaches work only in bright environments in which subtle photoplethysmographic and balli...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Chen W,Hernandez J,Picard RW

    更新日期:2018-10-30 00:00:00

  • Nonlinear model predictive control of glucose concentration in subjects with type 1 diabetes.

    abstract::A nonlinear model predictive controller has been developed to maintain normoglycemia in subjects with type 1 diabetes during fasting conditions such as during overnight fast. The controller employs a compartment model, which represents the glucoregulatory system and includes submodels representing absorption of subcut...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Hovorka R,Canonico V,Chassin LJ,Haueter U,Massi-Benedetti M,Orsini Federici M,Pieber TR,Schaller HC,Schaupp L,Vering T,Wilinska ME

    更新日期:2004-08-01 00:00:00

  • Compressive sensing in electrical impedance tomography for breathing monitoring.

    abstract:OBJECTIVE:Electrical impedance tomography (EIT) is a functional imaging technique in which cross-sectional images of structures are reconstructed based on boundary trans-impedance measurements. Continuous functional thorax monitoring using EIT has been extensively researched. Increasing the number of electrodes, number...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Shiraz A,Khodadad D,Nordebo S,Yerworth R,Frerichs I,van Kaam A,Kallio M,Papadouri T,Bayford R,Demosthenous A

    更新日期:2019-04-03 00:00:00

  • Recording of ENGs from the nerves innervating the pancreas of a dog during the intravenous glucose tolerance test.

    abstract::Electroneurograms (ENGs) from the vagus nerve (VN), the splanchnic nerve (SN) and the pancreatic nerve (PN) innervating the pancreas of a dog, were recorded with chronically implanted 33-electrode spiral cuffs (cuff) before and after the pancreas were stimulated with intravenously (i.v.) administered glucose. In the c...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Rozman J,Zorko B,Bunc M,Mikac U,Tegou E

    更新日期:2002-11-01 00:00:00

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Shiffman CA

    更新日期:2013-11-01 00:00:00

  • Modelling the cerebral haemodynamic response in the physiological range of PaCO2.

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Minhas JS,Panerai RB,Robinson TG

    更新日期:2018-06-19 00:00:00

  • Feasibility of long-term cerebral and peripheral regional tissue oxygen saturation measurements.

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    authors: Schmitz J,Pichler G,Schwaberger B,Urlesberger B,Baik N,Binder C

    更新日期:2014-07-01 00:00:00

  • Home monitoring of within-breath respiratory mechanics by a simple and automatic forced oscillation technique device.

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Dellacà RL,Gobbi A,Pastena M,Pedotti A,Celli B

    更新日期:2010-04-01 00:00:00

  • A multi-frequency EIT system design based on telecommunication signal processors.

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Robitaille N,Guardo R,Maurice I,Hartinger AE,Gagnon H

    更新日期:2009-06-01 00:00:00

  • EIT data noise evaluation in the clinical environment.

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Meeson S,Blott BH,Killingback AL

    更新日期:1996-11-01 00:00:00

  • Cardiac eigen imaging: a novel method to isolate cardiac activity in thoracic electrical impedance tomography.

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    pub_type: 杂志文章


    authors: Arshad SH,Murphy EK,Callahan JM,DeVries JT,Odame KM,Halter RJ

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    pub_type: 杂志文章


    authors: Jekova I,Cansell A,Dotsinsky I

    更新日期:2001-05-01 00:00:00

  • The contribution of vascular smooth muscle, elastin and collagen on the passive mechanics of porcine carotid arteries.

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    authors: Kochová P,Kuncová J,Svíglerová J,Cimrman R,Miklíková M,Liška V,Tonar Z

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    pub_type: 杂志文章


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    pub_type: 杂志文章


    authors: Pettersen FJ,Ferdous H,Kalvøy H,Martinsen ØG,Høgetveit JO

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  • The effect of serial data collection on the accuracy of electrical impedance tomography images.

    abstract::There has been a surge of interest in using electrical impedance tomography (EIT) for monitoring regional lung ventilation, however, EIT is an ill-conditioned problem, and errors/noise in the boundary voltages can have an undesirable effect on the quality of the final image. Most EIT systems in clinical usage use seri...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Yerworth R,Bayford R

    更新日期:2013-06-01 00:00:00

  • Non-contact video-based vital sign monitoring using ambient light and auto-regressive models.

    abstract::Remote sensing of the reflectance photoplethysmogram using a video camera typically positioned 1 m away from the patient's face is a promising method for monitoring the vital signs of patients without attaching any electrodes or sensors to them. Most of the papers in the literature on non-contact vital sign monitoring...

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    pub_type: 杂志文章


    authors: Tarassenko L,Villarroel M,Guazzi A,Jorge J,Clifton DA,Pugh C

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    abstract::The ability to image the impedance changes that accompany neuronal depolarization in the brain would constitute a major advance in neuroscience technology. Unfortunately, these changes are likely to be small and rapid and so difficult to measure. The impedance change at frequencies above 10 kHz, as used by conventiona...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Boone KG,Holder DS

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Gutiérrez-Juárez G,Vargas-Luna M,Córdova T,Varela JB,Bernal-Alvarado JJ,Sosa M

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  • Phase shift between respiratory oscillations in cerebral blood flow velocity and arterial blood pressure.

    abstract::We aim to investigate whether phase shift between respiratory oscillations in cerebral blood flow velocity (CBFV) and arterial blood pressure (ABP) is associated with changes in cerebral autoregulation (CA) or reflects the mechano-elastic properties of the cerebrovascular bed. The relationships between respiratory pha...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Uryga A,Placek MM,Wachel P,Szczepański T,Czosnyka M,Kasprowicz M

    更新日期:2017-02-01 00:00:00

  • Classification of cognitive reserve in healthy older adults based on brain activity using support vector machine.

    abstract:OBJECTIVE:Cognitive reserve (CR) refers to the capacity of the brain to actively cope with damage via the implementation of remedial cognitive processes. Traditional CR measurements focus on static proxies, which may not be able to appropriately estimate dynamic changes in CR. This study therefore investigated the cogn...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Yang CY,Lin CP

    更新日期:2020-07-07 00:00:00

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Jervis B,Belal S,Camilleri K,Cassar T,Bigan C,Linden DE,Michalopoulos K,Zervakis M,Besleaga M,Fabri S,Muscat J

    更新日期:2007-08-01 00:00:00

  • Adaptive filtering of ECG interference on surface EEnGs based on signal averaging.

    abstract::An external electroenterogram (EEnG) is the recording of the small bowel myoelectrical signal using contact electrodes placed on the abdominal surface. It is a weak signal affected by possible movements and by the interferences of respiration and, principally, of the cardiac signal. In this paper an adaptive filtering...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Garcia-Casado J,Martinez-de-Juan JL,Ponce JL

    更新日期:2006-06-01 00:00:00

  • Assessment of cerebrospinal fluid outflow conductance using an adaptive observer--experimental and clinical evaluation.

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Andersson K,Manchester IR,Andersson N,Shiriaev A,Malm J,Eklund A

    更新日期:2007-11-01 00:00:00

  • Transthoracic impedance study with large self-adhesive electrodes in two conventional positions for defibrillation.

    abstract::External defibrillation requires the application of high voltage electrical impulses via large external electrodes, placed on selected locations on the thorax surface. The position of the electrodes is one of the major determinants of the transthoracic impedance (TTI) which influences the intracardiac current flow dur...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Krasteva V,Matveev M,Mudrov N,Prokopova R

    更新日期:2006-10-01 00:00:00

  • Magnetographic assessment of fetal hiccups and their effect on fetal heart rhythm.

    abstract::Fetal hiccups emerge as early as nine weeks post-conception, being the predominant diaphragmatic movement before 26 weeks of gestation. They are considered as a programmed isometric inspiratory muscle exercise of the fetus in preparation for the post-natal respiratory function, or a manifestation of a reflex circuitry...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Popescu EA,Popescu M,Bennett TL,Lewine JD,Drake WB,Gustafson KM

    更新日期:2007-06-01 00:00:00