Reflex Triggering Properties in Genetic Generalized and Focal Epilepsies by Questioning and Neuropsychological Electroencephalography Activation Methods

Abstract

Objectives: Epileptogenesis is still not clearly understood. Therefore, there is an inevitable need for research that investigates triggers for reflex seizures and neuropsychological activation (NPA) methods using electroencephalography (EEG) in different epileptic syndromes. In this regard, we aimed to examine the characteristics and frequency of triggers for reflex seizures as well as changes in the frequency of epileptiform discharges (EDs), according to the stimulus in patients with generalized genetic epilepsy (GGE) and drug- resistant focal epilepsy (FE) by performing a comparative study with a survey and a neuropsychological EEG activation method, besides routine EEG.Methods:A detailed and structured survey questioning seizure triggers was applied to patients with FE and GGE. Afterward, the changes in EDs in juvenile myoclonic epilepsy (JME), absence epilepsy (AE), and resistant FE groups were examined using NPA methods with EEG.Results:The most frequently reported triggers in all patient groups (n=66) were sleep deprivation (68.2%), stress (65.3%), fatigue/physical stress (53%), awakening (42.4%), and light stimuli (25.8%). There was no significant difference between the JME (n=34), AE (n=16), and resistant FE (n=16) groups in terms of either the triggering or inhibition of EDs in EEG by conventional activation and NPA methods. While the triggering of EDs occurred in 24% of patients by hyperventilation and in 18.1% of patients by intermittent photic stimulation, a similar triggering rate was detected in 21.2% of patients by NPA methods. In addition, while the results of the conventional EEG activation methods were negative, a triggered ED was observed in six patients during NPA (11%). Only two patients showed an inhibition by the NPA methods. Four patients had EDs on their EEGs during the NPA methods associated with triggers reported in the questionnaire.Conclusion:In 11% of patients, while an ED was not seen in conventional methods, we observed that ED triggering occurred with the NPA methods. Planning the NPA methods for specific triggers during EEG recordings by prior questioning on the seizure triggers of the patients and applying NPA as an additional triggering method, especially for patients who do not have EDs in EEG with standard activation methods, may be beneficial in terms of the correct diagnosis.

Keywords

• neuropsychological eeg activation methods
• reflex epilepsy
• survey