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Monitoring Unit (monitoring + unit)
Selected AbstractsTonic,Absence Seizures: An Underrecognized Seizure TypeEPILEPSIA, Issue 3 2003Tina T. Shih M.D. Summary: ,Purpose: The individual electroclinical patterns,tonic seizures with generalized paroxysmal fast activity (GPFA, activity >13 Hz), and absence seizures with generalized slow spike-and-wave activity (GSS&W, <3 Hz),have been extensively described in the literature. However, only passing reference was made to the pattern of GPFA followed by GSS&W. In addition, these descriptions were formulated in the pre-EMU (Epilepsy Monitoring Unit) era, without benefit of video/clinical correlation. We now characterize this underrecognized seizure type. Methods: We retrospectively reviewed the data from eight patients with seizures that demonstrated this stereotyped EEG and clinical pattern. Results: We identified eight patients (six female patients; age 6,29 years; age at seizure onset, neonate to 10 years) who were evaluated at the Columbia University Epilepsy Monitoring Units between 1993 and 2002. All eight had an International League Against Epilepsy (ILAE) diagnosis of symptomatic generalized epilepsy, with six of eight manifesting multiple seizure types, six of eight with mild static encephalopathy, and two with normal cognition. A total of 29 seizures of this pattern was recorded; 26 of 29 seizures demonstrated GPFA (frequency between 14 and 30 Hz, lasting 2,8 s) followed by GSS&W (frequency range between 1 and 2 Hz, lasting 3,50 s). The predominant clinical correlate was bilateral tonic activity followed by a period of inattentiveness. In general, these seizures were differentiated from the patient's typical tonic seizures by this protracted period of impaired attentiveness. Conclusions: We describe a heretofore underrecognized and poorly characterized seizure type in patients with symptomatic generalized epilepsy, which we have termed tonic,absence seizures. Clinically and electrographically, this consists of a tonic seizure with GPFA followed by an absence seizure with GSS&W. [source] Record-linkage methodology for prescribing researchJOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 4 2001G. Libby BSc Record-linkage refers to the linking together of data relating to the same individual from separate source files. In this paper, we discuss ways in which the technique can enhance observational prescribing research in large populations. We draw upon the work of the Medicines Monitoring Unit (MEMO), University of Dundee, to illustrate its contribution to prescribing research. [source] Tonic,Absence Seizures: An Underrecognized Seizure TypeEPILEPSIA, Issue 3 2003Tina T. Shih M.D. Summary: ,Purpose: The individual electroclinical patterns,tonic seizures with generalized paroxysmal fast activity (GPFA, activity >13 Hz), and absence seizures with generalized slow spike-and-wave activity (GSS&W, <3 Hz),have been extensively described in the literature. However, only passing reference was made to the pattern of GPFA followed by GSS&W. In addition, these descriptions were formulated in the pre-EMU (Epilepsy Monitoring Unit) era, without benefit of video/clinical correlation. We now characterize this underrecognized seizure type. Methods: We retrospectively reviewed the data from eight patients with seizures that demonstrated this stereotyped EEG and clinical pattern. Results: We identified eight patients (six female patients; age 6,29 years; age at seizure onset, neonate to 10 years) who were evaluated at the Columbia University Epilepsy Monitoring Units between 1993 and 2002. All eight had an International League Against Epilepsy (ILAE) diagnosis of symptomatic generalized epilepsy, with six of eight manifesting multiple seizure types, six of eight with mild static encephalopathy, and two with normal cognition. A total of 29 seizures of this pattern was recorded; 26 of 29 seizures demonstrated GPFA (frequency between 14 and 30 Hz, lasting 2,8 s) followed by GSS&W (frequency range between 1 and 2 Hz, lasting 3,50 s). The predominant clinical correlate was bilateral tonic activity followed by a period of inattentiveness. In general, these seizures were differentiated from the patient's typical tonic seizures by this protracted period of impaired attentiveness. Conclusions: We describe a heretofore underrecognized and poorly characterized seizure type in patients with symptomatic generalized epilepsy, which we have termed tonic,absence seizures. Clinically and electrographically, this consists of a tonic seizure with GPFA followed by an absence seizure with GSS&W. [source] Independent Component Analysis Removing Artifacts in Ictal RecordingsEPILEPSIA, Issue 9 2004Elena Urrestarazu Summary:,Purpose: Independent component analysis (ICA) is a novel algorithm able to separate independent components from complex signals. Studies in interictal EEG demonstrate its usefulness to eliminate eye, muscle, 50-Hz, electrocardiogram (ECG), and electrode artifacts. The goal of this study was to evaluate the usefulness of ICA in removing artifacts in ictal recordings with a known EEG onset. Methods: We studied 20 seizures of nine patients with focal epilepsy monitored in our video-EEG monitoring unit. ICA was applied to remove obvious artifacts in segments at the beginning of the seizure. The final EEGs were exported to the original format and were compared with the original EEG by two blinded examiners. We compared original recordings and the samples cleaned by digital filters (DFs), ICA and ICA plus digital filters (ICA + DFs), evaluating the possibility of finding an ictal pattern, the localization of the onset in area and time, and the global quality of the sample. Results: All the recordings except one (95%) improved after the use of ICA for the elimination of blinking and other artifacts. Three seizures were found in which in the original recordings did not permit us to detect an ictal pattern, and after ICA + DFs, an ictal onset was evident; in two of them, ICA alone was able to show this pattern. The best results in all the scores were obtained with ICA + DF. ICA was better than DFs. The agreement between the two reviewers was highly significant. Conclusions: ICA is useful to remove artifacts from ictal recordings. When applied to ictal recordings, it increases the quality of the recording. In some cases, ICA may be useful to show ictal onsets obscured by artifacts. ICA + DFs obtained the best results regarding removal of the artifacts. [source] Analysing disruptive potential: the case of wireless local area network and mobile communications network companiesR & D MANAGEMENT, Issue 1 2005Stefan Hüsig In this article, we analyse the prediction that wireless local area network (W-LAN) technologies will be disruptive for incumbent mobile communications network operators. For this purpose, we develop a methodology of guided interviews to assess technologies for their disruptive characteristics based on theory of disruptive technology developed by Christensen (1997) and recent extensions. The application of our comprehensive step-by-step method improves the precision of the disruptive technology concept and its usability for practitioners to make ex ante distinctions between disruptive technologies and other phenomena caused by emerging technologies. Our method predicts that contrary to common assumptions, W-LAN is not likely to represent a disruptive technology for the established mobile communications network firms in terms of Christensen's concept. This research was conducted in close collaboration with Vodafone Pilotentwicklung, an R&D and technology monitoring unit of the Vodafone Group. Vodafone provided part of the empirical data through expert interviews and market reports. [source] Fluoride concentrations in antler bone of roe deer (Capreolus capreolus) indicate decreasing fluoride pollution in an industrialized area of western GermanyENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2001Uwe Kierdorf Abstract In order to reconstruct temporal changes in ambient fluoride levels in the industrialized Ruhr area (western Germany), we analyzed the bone fluoride content of 167 antlers of roe deer (Capreolus capreolus) killed between 1951 and 1999 in the northern part of this region. Individual values ranged between 110 and 8,178 mg F,/kg ash, and there was an overall marked decrease over the sampling period. Average bone fluoride concentrations in antlers from the periods 1980 through 1989 (geometric mean [95% confidence interval]: 1,490 [1,193,1,861] mg/kg ash) and 1990 through 1999 (753 [644,882] mg/kg ash) differed significantly (p < 0.001) and were both significantly (p < 0.001) lower than those from the periods 1951 through 1969 (3,720 [3,227,4,288] mg/kg ash) and 1970 through 1979 (2,573 [2,203,3,006] mg/kg ash). The findings are seen as indicative of a progressively reduced atmospheric fluoride deposition into the study area, caused by effective emission-control measures in Germany and neighboring countries. Because antlers are replaced annually, grow during a fixed period of some months, and are regularly collected and kept as trophies, they are well suited as monitoring units for analyzing temporal trends in environmental pollution by fluoride and other bone-seeking pollutants. [source] |