1. The following statement about the role of EEG in evaluation of a seizure is true.
1. A normal EEG rules out epilepsy and the diagnosis is probably non epileptic seizure.
2. It is difficult to differentiate between generalized and partial seizures using an EEG
3. If the EEG is taken when there is no epilepsy activity there will be no abnormality in the EEG.
4. EEG is highly non specific as it can be modified by drugs and other co-morbid diseases like migraine.

Answer: The correct answer is (d). The electroencephalogram (EEG) is an essential study in the diagnostic evaluation of epileptic seizures. If abnormal, the EEG may substantiate the diagnosis of epileptic seizures and indicate whether a patient may have generalized or partial seizures. Obtaining the EEG in the sleep-deprived state and using provocative measures during the test, such as hyperventilation and intermittent photic stimulation, increase the yield.

An abnormal EEG that confirms the clinical diagnosis of epilepsy substantially increases the likelihood that the patient will experience a second seizure over the next two year. However, a normal EEG does not rule out epilepsy, and a positive EEG may be nonspecific. As an example, certain types of EEG abnormalities are seen in patients with migraine headaches or in association with medications.