Journal of clinical neurophysiology : official publication of the American Electroencephalographic Society
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Status epilepticus (SE) is a condition wherein epileptic seizure discharges are sufficiently prolonged or repetitive so as to produce persistent alterations in neurologic function and in the underlying physiologic and neurochemical activities of the brain. Thus, the definition of SE now includes any disorder in which there is sustained and prolonged excitation of neurons. Electroencephalographic (EEG) patterns associated with specific types of SE are important components in their classification. ⋯ Progressive behavioral and electrical changes have not been reported in primarily generalized forms of SE. EEG is an important tool for verifying successful treatment of SE if the patient does not immediately recover neurologic function. EEG recordings also contribute substantially to understanding the mechanisms of, and development of better treatments for, human SE through their use in the study of experimental SE in the laboratory.
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J Clin Neurophysiol · Nov 1994
ReviewQuantitative sensory testing: methodology, applications, and future directions.
Quantitative sensory testing (QST) is based on well-developed psychophysical methods that define not only the stimulus (type, characteristics, quantity, presentation, testing format, and environment) but also the response (form and analysis). With the availability of personal computers, transducers, electronic circuitry, and specially written software, it became possible to develop systems that delivered physical stimuli with waveforms that were precisely defined, quantitated, and graded over a broad range of magnitudes, and capable of eliciting unitary sensations. Specific algorithms of testing and finding threshold could now be programmed for exact and sequential error-free testing. ⋯ In detecting patterns of sensory abnormality, it can also suggest the presence of specific diseases and be used to follow the course of sensory loss. Finally, because it is the best approach to detect, characterize, and quantitate sensory abnormality, it is useful both in epidemiologic and controlled clinical trials. Although our review focuses especially on the approaches and system we have developed, other systems using standardized approaches are available allowing the evaluation of vibratory (VDT), cooling (CDT), and warming (WDT) detection thresholds and visual analog scaling of heat pain (HP VAS).
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J Clin Neurophysiol · Oct 1993
ReviewContinuous EEG and evoked potential monitoring in the neuroscience intensive care unit.
As with other methods long used in intensive care units (ICU) and operating rooms (OR), the goal of neuroscience ICU continuous EEG (NICU-CEEG) and evoked potential (NICU-EP) monitoring is to extend our powers of observation to detect abnormalities at a reversible stage. EEG is an appropriate monitoring tool because it is linked to cerebral metabolism, is sensitive to ischemia and hypoxemia, correlates with cerebral topography, detects neuronal dysfunction at a reversible stage, and is the best method for detecting seizure activity. When applied systematically, it can impact medical decision-making in 81% of monitored patients. ⋯ Real-time digitized EEG in particular has been a major advance. Within limits, somatosensory evoked potential monitoring (ICU-SEP) is useful in the prognosis of coma, but it is less helpful in monitoring focal cerebral ischemia. Brainstem auditory evoked potential monitoring has a relatively restricted role in the NICU but is helpful in distinguishing structural from nonstructural causes of coma and can supplement ICU-SEP in predicting outcome.