Video Electroencephalogram (EEG)
A video electroencephalogram is a diagnostic test used on patients with epilepsy to monitor seizures and record important data about them. This test, which takes place in a hospital setting, makes use of a split screen on a computer to visualize a video recording of the patient while simultaneously displaying EEG readings of the patient's brain activity.
Administered over a prolonged period, usually several days to a week, both the video and EEG recordings are stored so that brain activity before, during and after seizures can be evaluated. By monitoring and recording bodily reactions, video EEGs provide valuable information about the possible causes of the seizures being experienced and about appropriate treatments. These tests also help physicians assess whether further testing is necessary or whether a surgical procedure to control seizures is likely to be effective.
The Video EEG Procedure
Prior to the procedure, patients are usually required to stop taking their anti-seizure medication and may be asked to cut back on their sleep as well. These measures are taken to provoke seizural activity so it can be monitored. During the video EEG procedure, electrodes will be applied to the patient's scalp in order to record electrical activity in the brain. For this reason patients are reminded not to use hairsprays or gels before undergoing a video EEG.
During the examination, patients may be asked to look at a strobe light or to hold their breaths for brief periods. The procedure is painless and will include downtime. For extended intervals, patients will be free to read, do puzzles or watch television. Other than some greasy deposits in the hair where the electrodes were placed, there should be no after effects of the procedure.
Risks of a Video EEG
While video EEG monitoring is considered safe, there is a slight risk of triggering a sequence of seizures in an epileptic patient. The technician administering the test, however, is well-prepared to deal with such an eventuality and to administer anti-seizure medication if it becomes necessary.
Results of a Video EEG
After the procedure is over and a full analysis of the data has been completed, the doctor will go over the results with the patient. There may be significant information available regarding the underlying cause of the seizures and the location of the abnormal electrical functioning in brain. In many cases, the physician will be able to make more informed decisions about which medications may be helpful and if any lifestyle changes need to be made. Surgery may be recommended, particularly if the seizural activity is confined to one specific area of the brain.
It is also possible that the EEG monitoring results will prove to be inconclusive and that additional testing will be necessary. Such testing may involve PET scans, MRI scans or brain-imaging studies.