4. What diseases can be detected by EEG? What should I pay attention to during the examination? What diseases can be detected by EEG?
(1) Diagnosis of epilepsy: Up to now, EEG is one of the most important, valuable and convenient means in the auxiliary diagnosis of epilepsy. In addition to clinical manifestations, EEG can detect abnormal brain bioelectric phenomena during seizures and interictal periods. Nowadays, with the introduction of EEG monitor and dynamic EEG, EEG can record and observe EEG changes 24 hours a day, and can accurately record the seizure process during seizure, which is more accurate and scientific for the diagnosis of epilepsy. It is especially necessary or even decisive for atypical seizures, rare type of epilepsy and occult type of epilepsy, which are clinically difficult to diagnose. (2) For classification of epilepsy: EEG of all types of epilepsy has relative characteristics. For example, those with EEG showing high arrhythmia are mostly infantile spasms, those showing 3C/S spike-slow complex waves are mostly petit mal seizures, those showing intermittent spike waves are mostly grand mal seizures and psychomotor seizures, etc. More than 80% of focal epileptic waves are partial seizures or psychomotor seizures. The clinical classification of epilepsy based on what is seen on the EEG during and between seizures, combined with the location of the lesion, etiology and age of onset, is very helpful, especially for some cases with atypical clinical manifestations that are more convincing. (3) For differentiation from other diseases: clinically some seizure disorders are easily confused with epilepsy, and EEG examination is one of the important means of differentiation. For example, syncope, which is a transient loss of consciousness caused by transient acute cerebral circulatory disorder from various causes, is not easily distinguished from petit mal seizures and syncopal epilepsy clinically. In patients with syncope, the EEG interval is normal, and the seizures are mostly irregular 2-3C/S slow waves, and the evoked test cannot yield epileptic waves, while minor seizures of syncope have specific spike-slow synthesis waves, and epileptic waves can easily appear even in the interval, which can be distinguished. Before doing EEG, we should pay attention to the following: 1. Wash your head well and do not apply oily substances. 2. The EEG room should be quiet and comfortable. 3. Sleep well the night before (except for those deprived of sleep) and eat before doing it. 4. For those with febrile convulsions, it is better to do EEG after 10 days of cessation of symptoms.