Computer methods and programs in biomedicine
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The electroencephalogram (EEG) is a representative signal containing information about the condition of the brain. The shape of the wave may contain useful information about the state of the brain. However, the human observer cannot directly monitor these subtle details. ⋯ The results obtained indicate that entropy estimators can distinguish normal and epileptic EEG data with more than 95% confidence (using t-test). The classification ability of the entropy measures is tested using ANFIS classifier. The results are promising and a classification accuracy of about 90% is achieved.
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Comput Methods Programs Biomed · May 2005
Classification of EEG signals using neural network and logistic regression.
Epileptic seizures are manifestations of epilepsy. Careful analyses of the electroencephalograph (EEG) records can provide valuable insight and improved understanding of the mechanisms causing epileptic disorders. The detection of epileptiform discharges in the EEG is an important component in the diagnosis of epilepsy. ⋯ The comparisons between the developed classifiers were primarily based on analysis of the receiver operating characteristic (ROC) curves as well as a number of scalar performance measures pertaining to the classification. The MLPNN based classifier outperformed the LR based counterpart. Within the same group, the MLPNN based classifier was more accurate than the LR based classifier.
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Comput Methods Programs Biomed · Nov 2004
Quantifying agitation in sedated ICU patients using digital imaging.
Agitation is a significant problem in the Intensive Care Unit (ICU), affecting 71% of sedated adult patients during 58% of ICU patient-days. Subjective scale based assessment-methods focused primarily on assessing excessive patient motion are currently used to assess the level of patient agitation, but are limited in their accuracy and resolution. This research quantifies this approach by developing an objective agitation measurement from patient motion that is sensed using digital video image processing. ⋯ All trials were performed in the Christchurch Hospital Department of Intensive Care, with ethics approval from the Canterbury Ethics Committee. Results show good correlation with medical staff assessment with no false positive results during calm periods. Clinically, this initial agitation measurement method promises the ability to consistently and objectively quantify patient agitation to enable better management of sedation and agitation through optimised drug delivery leading to reduced length of stay and improved outcome.
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Comput Methods Programs Biomed · Oct 2004
Modelling of discrete spatial variation in epidemiology with SAS using GLIMMIX.
SAS provides a macro GLIMMIX, which can be used for modelling of discrete spatial variation in epidemiological studies, where data are aggregated into small areas such as municipalities or postcode sectors. The purpose of these models is primary to examine to what extent unmeasured spatially correlated variables can explain the outcome of interest. ⋯ The code is illustrated by analysing the well-known Scottish lip cancer dataset with GLIMMIX and the results are compared with a Markov chain Monte Carlo approach. The code gives epidemiologists and bio-statisticians an immediate tool for analysing discrete spatial models in a familiar statistical software package.
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Comput Methods Programs Biomed · Aug 2004
Migrating from target-controlled infusion to closed-loop control in general anaesthesia.
The target-controlled infusion (TCI) technique has been successfully and commercially used in clinical general anaesthesia with the intravenous anaesthetic agent propofol. The technique is based on a population pharmacokinetic model and is an open-loop control system. Closed-loop control requires a reliable and consistent signal for feedback utilisation. ⋯ This model was used as a design reference to develop a proportional integral (PI) closed-loop control system using SEP as the feedback measure. A serials of 10 trials were conducted to investigate the difference between continuous bolus injection and infusion, all under closed-loop control. The trials showed that the use of SEPs in closed-loop control of anaesthesia is feasible.