**9. Conclusion**

*Electroencephalography - From Basic Research to Clinical Applications*

*Occipital spike and wave discharges seen in panayiotopoulos syndrome [52].*

(**Figure 11**) [58].

Viral encephalitis is an inflammatory infectious neurological disease that affects the central nervous system (CNS) which triggers an immune response by the viral antigen causing damage to the brain parenchyma and associated with electrical disturbance of the brain activity [54]. Viral encephalitis is common in children with Herpes Simplex Virus (HSV) being the commonest agent for encephalitis in Pediatric population [54, 55]. EEG study is considered to be a part in the investigational work up in patients with viral encephalitis [56]. Patients with Herpes Simplex Encephalitis (HSE) found to have significant EEG changes in the early stage of the diagnosis. Unilateral Periodic Lateralized Epileptiform Discharges (PLED) is considered to be the most typical EEG finding which correlate with diagnosis of HSE [57] and found to have a good outcome as compared to bilateral periodic lateralized epileptiform discharges which associated with unfavorable prognosis

*Periodic lateralized epileptiform discharges (PLED) over the right central-temporal head regions seen in* 

**144**

**Figure 11.**

**Figure 10.**

*HSE [59].*

EEG is considered to be save non-invasive procedure since its first application early in the 20th century. This procedure is done by trained EEG technicians and it should be interpreted by Neurologist or expert Neurophysiologists in order to obtain a high quality report to reach a proper diagnosis and provide optimal management to the patient.

Performing EEG study in children can be a difficult task because of the great fear and anxiety in this age group patients, so its vitally important to properly prepare these patients to minimize EEG artifacts for better interpretation of the EEG report.

EEG is an essential neurophysiological study especially in Pediatric patients to differentiate epileptic form and non-epileptic events as the differential diagnosis for paroxysmal episodes in children is wide and varies according to certain age group.

Although the diagnosis of brain death is primarily made on clinical basis, EEG remains an important ancillary test for diagnostic confirmation of brain death.

### **Conflict of interest**

The author declares no conflict of interest.
