Journal of clinical neurophysiology : official publication of the American Electroencephalographic Society
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Within the past few years, there has been a renaissance of functional neurosurgery for the treatment of dystonic movement disorders. In particular, deep brain stimulation (DBS) has widened the spectrum of therapeutical options for patients with otherwise intractable dystonia. It has been introduced only with a delay after DBS became an accepted treatment for advanced Parkinson' disease (PD). ⋯ Because more energy is needed for stimulation than in other movement disorders such as PD, more frequent battery replacements are necessary, which results in relatively higher costs for chronic DBS. The study of intraoperative microelectrode recordings and of local field potentials by the implanted DBS electrodes has yielded new insights in the pathophysiology of dystonia. Larger studies are underway presently to validate the observations being made.
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J Clin Neurophysiol · Apr 2003
Case ReportsA case of area-specific stimulus-sensitive postanoxic myoclonus.
The authors report a case of area-specific stimulus-sensitive postanoxic myoclonus and discuss possible pathophysiology. A 71-year-old man sustained cardiorespiratory arrest that lasted 10 minutes and remained unresponsive. On the first EEG obtained 8 hours after the arrest there was no cerebral electrical activity before stimulation of the trigeminal-innervated areas. ⋯ The patient died 7 days after the arrest. Area-specific stimulus-sensitive postanoxic myoclonus is very rare. The regularity of generalized bursts of spike-wave activity (cortical response) in response to stimulation of trigeminal-innervated areas suggests that the resting EEG electrocerebral silence may have been a result of cortical suppression with disinhibition of stimulus-sensitive brainstem-generated myoclonus.
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J Clin Neurophysiol · Dec 2002
Comparative Study Clinical Trial Controlled Clinical TrialSmall fiber dysfunction predominates in Fabry neuropathy.
Fabry disease is an X-linked recessive disease with a reduction of lysosomal alpha galactosidase A and consecutive storage of glycolipids e.g., in the brain, kidney, skin, and nerve fibers. Cardinal neurologic findings are hypohidrosis, painful episodes, and peripheral neuropathy. So far, the neurophysiological findings regarding the extent of large and small fiber dysfunction are contradictory. ⋯ However, only six patients had pathologic VDT, 19 had increased CDT, and 25 had elevated HPDT at a high level of stimulation. In Fabry patients, small fiber dysfunction is more prominent than large fiber dysfunction, confirming previous findings of sural nerve biopsies. The results suggest a higher vulnerability of small-diameter nerve fibers than of the thickly myelinated fibers.
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This review describes the wide spectrum of episodic phenomena that can occur during sleep. These phenomena include arousal disorders of nonrapid eye movement (NREM) sleep, rapid eye movement (REM) sleep behavior disorder, movement disorders, psychiatric disorders, and epileptic seizures. Each of these entities is discussed in detail, focusing on their clinical manifestations, diagnosis, and treatment. Essential historic elements that distinguish these events and the role of video-EEG-polysomnography in their differential diagnosis are emphasized.
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J Clin Neurophysiol · Oct 2002
Review Comparative StudyAnesthesia for intraoperative neurophysiologic monitoring of the spinal cord.
Intraoperative neurophysiologic monitoring (INM) using somatosensory and motor evoked potentials (MEPs) has become popular to reduce neural risk and to improve intraoperative surgical decision making. Intraoperative neurophysiologic monitoring is affected by the choice and management of the anesthetic agents chosen. Because inhalational and intravenous anesthetic agents have effects on neural synaptic and axonal functional activities, the anesthetic effect on any given response will depend on the pathway affected and the mechanism of action of the anesthetic agent (i.e., direct inhibition or indirect effects based on changes in the balance of inhibitory or excitatory inputs). ⋯ The management of the physiologic milieu is also important as central nervous system blood flow, intracranial pressure, blood rheology, temperature, and arterial carbon dioxide partial pressure produce alterations in the responses consistent with the support of neural functioning. Finally, the management of pharmacologic neuromuscular blockade is critical to myogenic MEP recording in which some blockade may be desirable for surgery but excessive blockade may eliminate responses. A close working relationship of the monitoring team, the anesthesiologist, and the surgeon is key to the successful conduct and interpretation of INM.