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 per second) 3D visualization of the spatial distribution of the static electrical properties of the cervix tissue. History, advantages, disadvantages and aspects of the system development are also described. The algorithm for the tiny measuring array organization is given. New details of the backprojection method on the non-regular electrode array are discussed. Some pictures reconstructed from numerical simulated data are offered. 3D visualization of the test object and cervix is presented.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
V A C,Y V G,A V K,S A S,T S Tdoi
10.1088/0967-3334/33/5/849subject
Has Abstractpub_date
2012-05-01 00:00:00pages
849-62issue
5eissn
0967-3334issn
1361-6579journal_volume
33pub_type
杂志文章abstract::A photoacoustic technique is used for studying topically applied substance absorption in human skin. The proposed method utilizes a double-chamber PA cell. The absorption determination was obtained through the measurement of the thermal effusivity of the binary system substance-skin. The theoretical model assumes that...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/23/3/304
更新日期:2002-08-01 00:00:00
abstract::Energy scavenging has increasingly become an interesting option for powering electronic devices because of the almost infinite lifetime and the non-dependence on fuels for energy generation. Moreover, the rise of wireless technologies promises new applications in medical monitoring systems, but these still face limita...
journal_title:Physiological measurement
pub_type: 杂志文章,评审
doi:10.1088/0967-3334/30/9/R01
更新日期:2009-09-01 00:00:00
abstract:OBJECTIVE:Metal exposures have been linked with many adverse health outcomes affecting nearly every system in the body. Exposure to metals has been tracked primarily using blood. Blood metal concentrations have drawbacks as biomarkers stemming from the metals' short biologic half-lives, shipping and storage requirement...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aad947
更新日期:2018-08-31 00:00:00
abstract::Using the cross-sectional images taken with the zoom-in micro-tomography technique, we measured trabecular thicknesses of femur bones in postmortem rats. Since the zoom-in micro-tomography technique is capable of high resolution imaging of a small local region inside a large subject, we were able to measure the trabec...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/26/5/008
更新日期:2005-10-01 00:00:00
abstract::This paper discusses some important issues for the design of electrical impedance measurement systems intended for body fluid shift monitoring, in particular during dialysis treatments. We have studied two common signal generation systems: digital synthesis and carrier recovery. We have found that in prolonged measure...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/16/4/003
更新日期:1995-11-01 00:00:00
abstract::Monitoring the fetal behavior does not only have implications for acute care but also for identifying developmental disturbances that burden the entire later life. The concept, of 'fetal programming', also known as 'developmental origins of adult disease hypothesis', e.g. applies for cardiovascular, metabolic, hyperki...
journal_title:Physiological measurement
pub_type: 杂志文章,评审
doi:10.1088/1361-6579/aa5fca
更新日期:2017-05-01 00:00:00
abstract::In the clinical environment the reliable interpretation of EIT images depends on the quality of the data. In the electrically noisy hospital environment the system performance needs to be assessed for each clinical investigation. From the model of noise presented, a figure of merit for comparisons of system performanc...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/17/4a/006
更新日期:1996-11-01 00:00:00
abstract:OBJECTIVE:Observational studies suggest that obesity might have a Mendelian origin, but it is not clear if gene expression patterns observed in obese subjects are secondary to genetic traits or not. APPROACH:Here we test a transcriptomic signature of obesity previously identified by our group on a large cohort of twin...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aab85a
更新日期:2018-04-26 00:00:00
abstract::The literature concerning measurement of spatial resolution in electrical impedance tomography (EIT) is vague. Different groups often use their own method or a modified version of a better known method, thus hindering a generalized resolution measurement which could be useful for gauging the performance of one system ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/23/1/316
更新日期:2002-02-01 00:00:00
abstract::The results of a preliminary clinical evaluation of a one-frequency electrical impedance tomography (EIT) system enabling static in vivo imaging are presented. The design of the measuring system and image reconstruction software are described. Thirty-one subjects were examined and divided into four clinical groups. Th...
journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/23/1/304
更新日期:2002-02-01 00:00:00
abstract::Fluorine (F) plays an important role in dental health and bone formation. Many studies have shown that excess fluoride (F(-)) can result in dental or skeletal fluorosis, while other studies have indicated that a proper dosage of fluoride may have a protective effect on bone fracture incidence. Fluorine is stored almos...
journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/33/2/243
更新日期:2012-02-01 00:00:00
abstract::The measurement of the complex respiratory impedance at a high temporal resolution is described. The measurement of impedance is correlated with the breathing cycle using electrical transthoracic impedance. This allows the determination of the complex impedance at any fixed point in the respiratory cycle, which result...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/14/3/019
更新日期:1993-08-01 00:00:00
abstract::We present a method for location of fetal QRS in maternal abdominal ECG recordings. This method's initial, global approach was proposed in the context of the 2013 PhysioNet/Computing in Cardiology Challenge where it was tested on the 447 four channel one-minute recordings.The first step is filtering to eliminate basel...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/35/8/1699
更新日期:2014-08-01 00:00:00
abstract::An analytic solution of the potential distribution on a 2D homogeneous disk for electrical impedance tomography under the complete electrode model is expressed via an infinite system of linear equations. For the shunt electrode model with two electrodes, our solution coincides with the previously derived solution expr...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/32/9/008
更新日期:2011-09-01 00:00:00
abstract::Temporal changes in the impedance spectra of bioelectrodes in contact with skin provide useful data for comparisons between differing electrode materials and skin preparation methods. Traditional impedance measuring systems employ swept frequency methods which will distort results in the impedance spectra of a sample ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/20/1/008
更新日期:1999-02-01 00:00:00
abstract::The electrocardiogram is a representative signal containing information about the condition of the heart. The shape and size of the P-QRS-T wave, the time intervals between its various peaks, etc may contain useful information about the nature of disease affecting the heart. However, the human observer cannot directly...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/25/5/005
更新日期:2004-10-01 00:00:00
abstract::A time-varying parametric spectrum estimation method for analysing non-stationary heart rate variability signals is presented. As a case study, the dynamics of heart rate variability during an orthostatic test is examined. In this method, the non-stationary signal is first modelled with a time-varying autoregressive m...
journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/27/3/002
更新日期:2006-03-01 00:00:00
abstract::A method was developed for simultaneously measuring plasma resistance, cell interior resistance and cell membrane capacitance of blood. A three-element circuit model for simulating the impedance of blood was evaluated by comparing measured and calculated impedance frequency curves and was found feasible. The values of...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/14/2/006
更新日期:1993-05-01 00:00:00
abstract::It has previously been shown that extreme changes in ambient air temperature can affect whole-body bioelectrical impedance. The purpose of this study was to determine if more moderate changes in ambient air temperature, such as those experienced in most laboratory settings, would also affect bioelectric impedance anal...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/25/1/011
更新日期:2004-02-01 00:00:00
abstract::In this study, we designed and tested a new algorithm, which we call the 'restricted parabola', to identify the optimum atrioventricular (AV) delay in patients with biventricular pacemakers. This algorithm automatically restricts the hemodynamic data used for curve fitting to the parabolic zone in order to avoid inadv...
journal_title:Physiological measurement
pub_type: 杂志文章,随机对照试验
doi:10.1088/0967-3334/36/9/1889
更新日期:2015-09-01 00:00:00
abstract::The holy grail of neuroimaging would be to have an imaging system, which could image neuronal electrical activity over milliseconds. One way to do this would be by imaging the impedance changes associated with ion channels opening in neuronal membranes in the brain during activity. In principle, we could measure this ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/25/1/040
更新日期:2004-02-01 00:00:00
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
doi:10.1088/0967-3334/30/3/006
更新日期:2009-03-01 00:00:00
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
doi:10.1088/0967-3334/28/10/008
更新日期:2007-10-01 00:00:00
abstract::In this study, a framework for the characterization of the dynamic interactions between RR variability (RRV) and systolic arterial pressure variability (SAPV) is proposed. The methodology accounts for the intrinsic non-stationarity of the cardiovascular system and includes the assessment of both the strength and the p...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/33/3/315
更新日期:2012-03-01 00:00:00
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
doi:10.1088/0967-3334/23/2/304
更新日期:2002-05-01 00:00:00
abstract::Non-contact vital sign monitoring enables the estimation of vital signs, such as heart rate, respiratory rate and oxygen saturation (SpO2), by measuring subtle color changes on the skin surface using a video camera. For patients in a hospital ward, the main challenges in the development of continuous and robust non-co...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab525c
更新日期:2019-12-02 00:00:00
abstract:OBJECTIVE:Transfer function analysis (TFA) of dynamic cerebral autoregulation (dCA) requires smoothing of spectral estimates using segmentation of the data (SD). Systematic studies are required to elucidate the potential influence of SD on dCA parameters. APPROACH:Healthy subjects (HS, n = 237) and acute ischaemic str...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab7ddf
更新日期:2020-04-17 00:00:00
abstract:OBJECTIVE:Predictive analytics monitoring that informs clinicians of the risk for failed extubation would help minimize both the duration of mechanical ventilation and the risk of emergency re-intubation in ICU patients. We hypothesized that dynamic monitoring of cardiorespiratory data, vital signs, and lab test result...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aace95
更新日期:2018-07-16 00:00:00
abstract::This paper introduces a new clinical distortion index able to measure the decrease in diagnostic content in compressed echocardiograms. It is calculated using cardiologists' answers to a clinical testbed composed of two types of tests: one blind and the other semi-blind. This index may be used to compare clinical perf...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/30/5/001
更新日期:2009-05-01 00:00:00
abstract::Multiple frequency bio-electrical impedance analysis (MFBIA) may be useful for monitoring fluid balance in newborn infants or to provide early prediction of the outcome following perinatal asphyxia. A reference range of data is needed for identification of babies with abnormal impedance values. This was a cross-sectio...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/27/11/010
更新日期:2006-11-01 00:00:00