Abstract:
:In this study, the selection of coil configuration parameters (coil radius and coil centre shift) for induced current EIT using circular coils is investigated. An alternative coil configuration is suggested, which produces approximately linear (spatially) magnetic fields in order to strengthen the currents in the central region. Injected current EIT, with Sheffield data collection protocol, and induced current EIT, with two different coil configurations, are compared with respect to singular-value patterns, sensitivity distributions and imaging performances. It is observed that for the proposed alternative coil configuration the measurements are more sensitive to inner region conductivity perturbations when compared to injected current EIT and induced current EIT using circular coils. The images obtained by induced current EIT are comparable to that obtained by injected current EIT.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Gençer NG,Ider YZdoi
10.1088/0967-3334/15/2a/007subject
Has Abstractpub_date
1994-05-01 00:00:00pages
A51-7eissn
0967-3334issn
1361-6579journal_volume
15 Suppl 2apub_type
杂志文章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
doi:10.1088/0967-3334/16/3a/009
更新日期:1995-08-01 00:00:00
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
doi:10.1088/0967-3334/37/1/83
更新日期:2016-01-01 00:00:00
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
doi:10.1088/1361-6579/38/2/310
更新日期:2017-02-01 00:00:00
abstract::Electrical impedance tomography (EIT) is very sensitive to deformations of the medium boundary shape. For lung imaging, breathing and changes in posture move the electrodes and change the chest shape, resulting in image artefacts. Several approaches have been proposed to improve the reconstructed images; most methods ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/29/6/S08
更新日期:2008-06-01 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::Obesity is associated with abnormal cardiac regulation by the autonomic nervous system (ANS), this being reversed by weight loss. Bariatric (weight-reduction) surgery can induce substantial long-term weight reductions. This study compares the acute influence on ANS control of two different types of bariatric surgery i...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/30/7/002
更新日期:2009-07-01 00:00:00
abstract::We used the finite element (FE) method to estimate the spatial sensitivity of a needle electrode for bioimpedance measurements. This current conducting needle with an insulated shaft was inserted in a saline solution and the current was measured at the neutral electrode. Model resistance and reactance were calculated ...
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
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::There is a lack of studies that examine the dynamics of heat-induced shrinkage of organ tissues. Clinical procedures such as radiofrequency ablation, microwave ablation or high-intensity focused ultrasound, use heat to treat diseases such as cancer and cardiac arrhythmia. When heat is applied to tissues, shrinkage occ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/35/1/55
更新日期:2014-01-01 00:00:00
abstract::This paper presents the design, construction and testing of a device to measure pressure-volume loops in the left ventricle of conscious, ambulatory rats. Pressure is measured with a standard sensor, but volume is derived from data collected from a tetrapolar electrode catheter using a novel admittance technique. Ther...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/32/6/007
更新日期:2011-06-01 00:00:00
abstract:OBJECTIVE:The aim of this study was to monitor the physiological changes and cytotoxic effects of exogenous contrast agents during photoacoustic imaging (PAI) and photothermal therapy (PTT). In this paper, a low-power telemetric device for mouse vital signs monitoring was designed and demonstrated. APPROACH:The power ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aba6a1
更新日期:2021-01-01 00:00:00
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
doi:10.1088/0967-3334/23/4/309
更新日期:2002-11-01 00:00:00
abstract::This paper describes a method of reducing the influence of the data error caused by non-ideal boundary shape and electrode placement on reconstructed images. A data calibration and a modified Newton-Raphson reconstruction are combined in the method to ensure rapid convergence and small reconstruction error. The method...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/15/2a/022
更新日期:1994-05-01 00:00:00
abstract:OBJECTIVE:The aim of the study was to explore the feasibility of titrating tidal volume (V T) and positive end-expiratory pressure (PEEP) during one-lung ventilation (OLV) based on ventilation distribution and oxygenation. APPROACH:Twenty-four consecutive patients requiring intubation with a double-lumen tube and subs...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aaaeb2
更新日期:2018-03-29 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
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/26/2/003
更新日期:2005-04-01 00:00:00
abstract:OBJECTIVE:In this study, electroencephalography activity recorded during monotonous driving was investigated to examine the predictive capability of monopolar EEG analysis for fatigue/sleepiness in a cohort of train drivers. APPROACH:Sixty-three train drivers participated in the study, where 32- lead monopolar EEG dat...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aae42e
更新日期:2018-10-30 00:00:00
abstract:BACKGROUND:Uterine activity monitoring is an essential part of managing the progress of pregnancy and labor. Although intrauterine pressure (IUP) is the only reliable method of estimating uterine mechanical activity, it is highly invasive. Since there is a direct relationship between the electrical and mechanical activ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab37db
更新日期:2019-09-03 00:00:00
abstract:OBJECTIVE:Increased penetration of pulsatile power to the brain has been implicated in the pathogenesis of age-related cognitive dysfunction and dementia, a common comorbidity in patients with heart failure and preserved ejection fraction (HFpEF). However, there is a lack of knowledge on the effects of organic and inor...
journal_title:Physiological measurement
pub_type: 杂志文章,随机对照试验
doi:10.1088/1361-6579/aab2ef
更新日期:2018-04-20 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/34/6/713
更新日期:2013-06-01 00:00:00
abstract:OBJECTIVE:Evoked tympanic membrane displacement (TMD) is a non-invasive technique for assessing intracranial pressure (ICP). The aim of this study was to define reference intervals (RIs) in the healthy population. APPROACH:Measurements were made in 154 healthy adults. Results were quantified by V m, which is the most ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aaa1d3
更新日期:2018-01-31 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/37/10/1785
更新日期:2016-10-01 00:00:00
abstract:OBJECTIVE:Brain-computer interfaces (BCIs) are aimed at providing a new way of communication between the human brain and external devices. One of the major tasks associated with the BCI system is to improve classification performance of the motor imagery (MI) signal. Electroencephalogram (EEG) signals are widely used f...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aba07b
更新日期:2020-08-11 00:00:00
abstract::Electrical impedance tomography (EIT) could be significantly advantageous to continuous monitoring of lung development in newborn and, in particular, preterm infants as it is non-invasive and safe to use within the intensive care unit. It has been demonstrated that accurate boundary form of the forward model is import...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/35/6/1149
更新日期:2014-06-01 00:00:00
abstract::In recent AASM practice, parameter actimetry is cited to measure total sleep time in obstructive sleep apnoea patients, when polysomnography is not available. An actigraph was therefore compared to polysomnographic data in 28 subjects with known sleep disordered breathing. Total sleep time (TST), sleep period time (SP...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/31/12/005
更新日期:2010-12-01 00:00:00
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
doi:10.1088/0967-3334/33/5/849
更新日期:2012-05-01 00:00:00
abstract::One unfortunate occurrence in experimental measurements with electrical impedance tomography is electrodes which become detached or poorly connected, such that the measured data cannot be used. This paper presents an automatic approach to detect such erroneous electrodes. It is based on the assumption that all valid m...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/26/2/017
更新日期:2005-04-01 00:00:00
abstract::Current methods for analysing foetal heart rate (FHR) patterns have yet to meet their full potential in the recognition of hypoxia in the foetus. Following the recent suggestion that fractal analysis can be applied to FHR recordings, the current paper describes a method for distinguishing two simultaneous fractal dime...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/14/3/009
更新日期:1993-08-01 00:00:00
abstract::Using a primary coil that induces eddy currents in a volume conductor, and a pair of secondary coils configured to form a differential transformer, it is possible to measure the conductivity of a volume conductor by the magnetic fields of the induced eddy currents. This method is especially favourable for measuring im...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/14/4/007
更新日期:1993-11-01 00:00:00
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
doi:10.1088/0967-3334/24/2/310
更新日期:2003-05-01 00:00:00