We studied scalp-recorded auditory event-related potentials (ERPs) of 30 untreated patients with new-onset temporal lobe epilepsy and 30 age- and sex-matched normal controls. This study was designed to eliminate the effects of intractability of seizures and chronic use of antiepileptic drugs on P300 auditory ERPs. There were no statistically significant differences in both latency and amplitude of P300 between the two groups. Similar methods were also used to analyze component latencies and amplitudes of ERPs of 9 patients who had hippocampal sclerosis with comparison to control subjects. There were no statistically significant differences between these two groups as well. Our study evidently does not support temporal lobe sources of P300 scalp-recorded auditory ERPs. We also conclude that the scalp-recorded auditory ERPs procedure is not a useful tool to evaluate temporal lobe epilepsy.
The objective of this study was to determine if screening by a neurologist of all non-neurologist electroencephalogram (EEG) referrals prior to approval reduces the number of inappropriate requests. This retrospective survey included 600 consecutive EEG requisitions referred to the Anaheim Kaiser Permanente Neurodiagnostic Laboratory to rule out epilepsy. Patients with established epilepsy referred for a repeat EEG for management issues were excluded.Three groups of EEG referrals were analyzed. Each group consisted of 200 EEGs (1 00 pediatric and 100 adult EEGs). The first group was referred directly by non-neurologists, the second group was referred by non-neurologists with scrutiny by a neurologist, and the third group was referred by a neurologist directly. In the pediatric group, the ratio of abnormal EEG vs normal EEG was 1:3.35 in the first group, 1:0.69 in the second group and 1:0.33 in the third group. In the adult group, the ratio of abnormal EEGs vs normal EEGs was 1:2.23 in the first group, 1:0.82 in the second group and 1:0.45 in the third group. In the combined pediatric and adult groups, the ratio of abnormal EEG vs normal EEG was 1 :2.70 in the first group, 1 :0.75 in the second group and 1:0.39 in the third group. There was a significant difference between the results of the EEGs ordered by non-neurologists directly versus non-neurologists with scrutiny (p=.334, chi-square test).Scrutiny by a neurologist of EEG referrals from nonneurologists led to a reduction in the number of normal EEG results. This suggests that inappropriate EEG requests for non-epileptic patients that yield normal EEG results are significantly reduced with scrutiny. This can help reduce the indiscriminate overuse of EEGs by non-neurologists thereby leading to better utilization of healthcare resources.
Midline spikes are characterized by spike foci recorded at Cz, Fz, or Pz with amplitude ranging from 20 to 350 microvolts. Out of 7,929 EEGs performed at the Neurodiagnostics Laboratory, Kaiser Permanente Medical Center, Anaheim, California, between 1996 and 2006, 17 EEGs (0.21%) were identified as having interictal midline spikes with or without other epileptiform discharges. Eight EEGs showed midline spikes at Cz, 2 at Fz, 2 at Cz and Fz, 1 at Cz and C3, 1 at Cz, C3, and P3, 1 at Cz and F8, 1 at Cz and T4, and 1 at Cz with 2 Hz generalized spike and slow wave complex. Midline spikes were recorded in 10 males and 7 females. The age ranged from 4 days to 38-years-old with a mean age of 10.8 years. Twelve patients (70.6%) were children. Twelve patients (70.6%) had generalized tonic-clonic seizures and 5 had partial motor seizures. Of the 17 patients, 14 had no known causes, 1 had an agenesis of corpus callosum, 1 had a left frontal arteriovenous malformation, and 1 had a left frontal area stroke. We postulate that the mechanism for the genesis of midline spikes may be heterogeneous. Midline spikes may be triggered by thalamocortical network in a generalized tonic-clonic seizure, or may originate in the parasagittal cortex in a partial motor seizure.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.