Advertisement

Topics

Activating Effects of Sleep Deprivation on Synchronized MEG-EEG Recordings of Epilepsy Patients With Non-Diagnostic EEG

2014-08-27 03:54:51 | BioPortfolio

Summary

This study will evaluate how the state of being completely deprived of sleep has an effect on recordings of magnetoencephalography (MEG) and electroencephalography (EEG), in relation to how alert someone is and how sleepy someone perceives himself or herself to be. EEG measures electronic potential differences on the scalp. On the other hand, MEG is a non-invasive technique for recording the activity of neurons in the brain, through recording of magnetic fields caused by synchronized neural currents. It has the ability to detect seizures. Because magnetic signals of the brain vary, this technique must balance two key problems: weakness of the signal and strength of the noise. The EEG is sensitive to extra-cellular volume currents, whereas the MEG primarily registers intra-cellular currents. Because electrical fields are quite dependent on the conductive properties of the tissues, and magnetic fields are significantly less distorted by tissue, the MEG has better spatial resolution. There is a great deal of evidence that EEG and MEG provide complementary data about underlying currents of ions.

The complex relationship of sleep and epilepsy is well known. Sleep has been used for many years as a powerful EEG activator. Many researchers have supported the hypothesis that there is a specific activating effect of sleep deprivation on epileptic discharges. Sleep deprivation is defined as a sleepless state of longer than 24 hours. The increased use of MEG in diagnosis could improve the procedure for evaluating patients before surgery for epilepsy, by making invasive studies less necessary.

Patients 18 years of age or older, with a diagnosis of epilepsy and with a documented last routine EEG (at least 2 weeks earlier) and routine EEG on the day of a baseline MEG-EEG without interictal epileptiform discharges (IEDs) may be eligible for this study.

Participants will be rated according to the Epworth, Stanford, and Karolinska Sleepiness Scales, to determine their subjective sleepiness. They will be randomly assigned to stay awake all night or sleep in the hospital overnight. That is, a sleep deprivation and non-sleep deprivation synchronized MEG-EEG recording will be performed in random order. Then the sequence of sleep deprivation and non-sleep deprivation will be reversed within 14 to 21 days. During the recordings, the patient will either sit or lie with his or her head in a helmet covering the entire head, with openings for the eyes and ears. Brain magnetic fields will be recorded with a 275-channel OMEGA system. Throughout the session, visual and two-way audio communication will be maintained with the patient. Recording sessions will last 90 to 180 minutes, with the patient allowed to take breaks after at least 10 minutes in a scanner. Attempts will be made to encourage patients to stay awake and sleep for about the same amount of time during each recording, to acquire comparable amounts of sleep and awake recordings.

Description

Objective:

We would like to evaluate the activating effects of complete sleep deprivation (SD) on synchronized MEG-EEG recordings, and on each of the components singly, in relation to the degree of alertness during recording (awake vs. sleep) and the subjective degree of sleepiness as assessed by standardized scales. We postulate that acute SD will increase the diagnostic yield of synchronized MEG-EEG and activate both modalities (MEG, EEG) to the same degree. The increased diagnostic utility of MEG could improve the epilepsy surgery evaluation procedure for many patients by rendering invasive studies less necessary. The medical and economic utilization of such expensive resources as MEG could thus be rationalized.

Population:

Participants of this study will be epilepsy patients whose last routine interictal EEG (performed at least two weeks earlier), subsequent pre-screening EEG and screening MEG-EEG show no interictal epileptiform discharges (IEDs), and are therefore considered non-diagnostic.

Study Design/Methods:

We will use a 275-channel Whole-head MEG System (CTF Systems 2001 Inc.). Patients will have a screening, non-SD and SD MEG-EEG after their degree of sleepiness is assessed using the Epworth, Stanford and Karnolinska sleepiness scales. Starting one day after the MEG-EEG, SD and non-SDMEG-EEG will be performed in random order within 14-21 days of each other. This will ensure an equal amount of sampling effect in SD and non-SD data sets. The MEG-EEG session will last 90 to 180 minutes. Patients may take a break after at least 10 minutes in a scanner. We will attempt to record a comparable amount of awake and sleep data. At least thirty minutes of artifact-free baseline, non-SD and SD MEG-EEG will be analyzed. For the purpose of blinding, each modality will be read independently by two readers, each of whom will be blinded to the relationship of the MEG-EEG data to sleep deprivation, results obtained by the other modality and subjective degree of sleepiness. Only interpretations of each modality agreed upon by both readers will be accepted. When there is no agreement, a third independent reader will resolve the disagreement.

Outcomes:

The primary outcome measure will be the proportion of seizure foci detected and delineated after SD on synchronized MEG-EEG recordings. Comparisons will also be made for each recording modality and between them, according to the state of alertness during recording and subjective feeling of sleepiness before each recording.

Study Design

N/A

Conditions

Epilepsy

Location

National Institute of Neurological Disorders and Stroke (NINDS)
Bethesda
Maryland
United States
20892

Status

Completed

Source

National Institutes of Health Clinical Center (CC)

Results (where available)

View Results

Links

Published on BioPortfolio: 2014-08-27T03:54:51-0400

Clinical Trials [419 Associated Clinical Trials listed on BioPortfolio]

A Registration Study on Depression in Patients With Epilepsy

The prevalence of comorbid depression in patients with epilepsy is as high as 30-50%. The depressive symptoms severely affect seizure severity and quality of life in patients with epilepsy...

Genetic Study of Familial Epilepsy

OBJECTIVES: I. Determine the chromosomal regions that contain genes that raise the risk of epilepsy in families by performing genetic linkage analysis of idiopathic/cryptogenic epilepsy.

SANTE - Stimulation of the Anterior Nucleus of the Thalamus for Epilepsy

The purpose of this research is to study the safety and effectiveness of electrical stimulation to treat uncontrolled seizures in adults with epilepsy.

Ketogenic Diet Program for Epilepsy

This study will assess the effectiveness of the ketogenic diet (high-fat, low-carbohydrate, and moderate protein) in treating epilepsy. Two study groups will be comprised of children with ...

Cerebral Autoregulation in Patients With Epilepsy

The purpose of this study is to determine whether patients with epilepsy exhibiting impaired dCA, which may contribute to subsequent stroke.

PubMed Articles [856 Associated PubMed Articles listed on BioPortfolio]

Epilepsy in an elderly population: Classification, etiology and drug resistance.

To characterize epilepsy in an elderly population and describe the prevalence of drug resistant epilepsy (DRE) using recently validated International League Against Epilepsy (ILAE) criteria.

Perceived epilepsy stigma mediates relationships between personality and social well-being in a diverse epilepsy population.

Perceived epilepsy stigma and reduced social well-being are prevalent sources of distress in people with epilepsy (PWE). Yet, research on patient-level correlates of these difficulties is lacking, esp...

Occipital epilepsy versus progressive myoclonic epilepsy in a patient with continuous occipital spikes and photosensitivity in electroencephalogram: A case report.

Progressive myoclonic epilepsy (PME) is rare epilepsy syndrome. Although EEG is a useful neurophysiological technique in the evaluation of epilepsy, few EEG abnormalities have been described in PME. S...

Epilepsy-related concerns among patients with epilepsy in West China.

In the present study, we aimed to investigate patient-derived epilepsy-related concerns among Chinese individuals with epilepsy and the impact of seizure control on patient concerns.

Epilepsy may cause increased pain sensitivity: Evidence from absence epileptic WAG/Rij rats.

The comorbidity of epilepsy and pain disorders as well as effectiveness of certain therapeutic approaches in both conditions attracted attention to epilepsy-pain interactions. This lead to the discove...

Medical and Biotech [MESH] Definitions

A disorder characterized by the onset of myoclonus in adolescence, a marked increase in the incidence of absence seizures (see EPILEPSY, ABSENCE), and generalized major motor seizures (see EPILEPSY, TONIC-CLONIC). The myoclonic episodes tend to occur shortly after awakening. Seizures tend to be aggravated by sleep deprivation and alcohol consumption. Hereditary and sporadic forms have been identified. (From Adams et al., Principles of Neurology, 6th ed, p323)

A disorder characterized by recurrent episodes of paroxysmal brain dysfunction due to a sudden, disorderly, and excessive neuronal discharge. Epilepsy classification systems are generally based upon: (1) clinical features of the seizure episodes (e.g., motor seizure), (2) etiology (e.g., post-traumatic), (3) anatomic site of seizure origin (e.g., frontal lobe seizure), (4) tendency to spread to other structures in the brain, and (5) temporal patterns (e.g., nocturnal epilepsy). (From Adams et al., Principles of Neurology, 6th ed, p313)

An anticonvulsant effective in tonic-clonic epilepsy (EPILEPSY, TONIC-CLONIC). It may cause blood dyscrasias.

An autosomal dominant inherited partial epilepsy syndrome with onset between age 3 and 13 years. Seizures are characterized by PARESTHESIA and tonic or clonic activity of the lower face associated with drooling and dysarthria. In most cases, affected children are neurologically and developmentally normal. (From Epilepsia 1998 39;Suppl 4:S32-S41)

A subtype of epilepsy characterized by seizures that are consistently provoked by a certain specific stimulus. Auditory, visual, and somatosensory stimuli as well as the acts of writing, reading, eating, and decision making are examples of events or activities that may induce seizure activity in affected individuals. (From Neurol Clin 1994 Feb;12(1):57-8)

More From BioPortfolio on "Activating Effects of Sleep Deprivation on Synchronized MEG-EEG Recordings of Epilepsy Patients With Non-Diagnostic EEG"

Advertisement
Quick Search
Advertisement
Advertisement

 

Relevant Topics

Sleep Disorders
Sleep disorders disrupt sleep during the night, or cause sleepiness during the day, caused by physiological or psychological factors. The common ones include snoring and sleep apnea, insomnia, parasomnias, sleep paralysis, restless legs syndrome, circa...

Alzheimer's Disease
Of all the types of Dementia, Alzheimer's disease is the most common, affecting around 465,000 people in the UK. Neurons in the brain die, becuase  'plaques' and 'tangles' (mis-folded proteins) form in the brain. People with Al...

Epilepsy
Epilepsy is defined as a disorder of brain function characterized by recurrent seizures that have a sudden onset.  (Oxford Medical Dictionary).  A seizure is caused by a sudden burst of excess electrical activity in the brain, causing a tempora...


Searches Linking to this Trial