The article presents three case reports confirming the phenomenon of “forced EEG normalization” described by Hans Landolt and the results of observation of four patients with mesotemporal epilepsy.

A number of epileptologists often diagnose Lennox-Gastaut syndrome, while others almost never do. It is necessary to understand why this is happening, especially since Lennox-Gastaut syndrome, according to literature descriptions, is quite common.

Aim. To systematize available data on Lennox-Gastaut syndrome, which will help to improve the quality of diagnosis and management of patients.

Materials and methods. Qualitative scientific publications from the International Scientific Databases (ISDS), including peer-reviewed journals and monographs, were selected for the review. The plan of the review included a brief description of the syndrome; seizure types; EEG features; diagnosis criteria; treatment.

Results and discussion. None of the seizure types are pathognomonic for Lennox-Gastaut  syndrome. The syndrome is considered to be confirmed if typical seizures (predominantly tonic) with typical interictal patterns without atypical EEG characteristics are reported. A diagnosis of the syndrome is considered probable if there are typical EEG patterns of waking and sleeping, but no tonic seizures are detected. The first choice of the treatment is valproate. Possible alternatives are lamotrigine and topiramate. Rufinamide and zonisamide are available as the second line of antiepileptic drugs. Rufinamide should be used when there is no effect from valproate and lamotrigine. Rufinamide also has antiabsance activity.

Conclusion. “Classic” Lennox-Gasto syndrome is rare. Cases of “probable” Lennox-Gasto syndrome are much more frequent, and not all criteria of its diagnosis are observed. Taken into account the blurring of the diagnosis criteria for Lennox-Gasto syndrome and data on the efficacy of rufinamide in children with another epilepsies, it is possible to use this drug not only for Lennox-Gasto syndrome, but also for other epileptic syndromes, especially those with dropattacks, tonic seizures and atypical absences. 

Genetic, or idiopathic, generalized epilepsies (GGEs or IGEs) includes childhood absence epilepsy (CAE), juvenile absence epilepsy (JAE), juvenile myoclonic epilepsy (JME), and epilepsy with generalized tonic-clonic seizures alone (GTCS-a).

Aim. to characterize the capabilities of electroencephalography (EEG) for the diagnosis of various forms of genetic generalized epilepsy

Materials and methods. Literature data in Pubmed, Google Scholar was analyzed. In addition, own observations and clinical cases were systematized.

Results. The article presents the data of morphology and topography of spike-wave discharges, as well as other patterns of EEG in the GGE – poly-spike activity, photoparoxysmal response, occipital intermittent rhythmic delta activity (OIRDA), fixation-off sensitivity and generalized paroxysmal fast activity (GPFA), as well as epileptiform K-complexes, the allocation of which in an independent pattern is questioned by a number of neurophysiologists. The differences between interictal and ictal activity in the GGE are discussed in detail; electroencephalogram (EEG) informativity modifiers are considered. The morphology of atypical features in the GGE is considered. The role of EEG in the differential diagnosis of CAE, JAE, JME, GTCS alone with the description of typical, atypical features, study scenarios and diagnostic criteria for each form are considered.

Conclusions. Typical EEG features of GGE significantly simplify the differential diagnosis of electroclinical syndromes. There are “non-classical” features of EEG in the GGE, which do not contradict the diagnosis. To reveal the peculiarities of epileptiform discharges distribution, video EEG monitoring with night-time sleep and the use of several modality stimuli is preferable. Incorrect interpretation of EEG is dangerous for the patient. 

Juvenile myoclonic epilepsy (JME) is a common disease. However, some aspects of etiology and pathogenesis are not yet fully clarified. This publication describes the development of ideas about JME, the types of seizures that occur in JME, provides a list of triggering factors and a prognosis severity scale that depending on these triggering factors. The section on JME diagnostics discusses methods of neuroimaging, electroencephalography, and approaches to assessing the mental status of JME patients. The data of meta-analysis of prevalence and risk factors of refractory JME in the context of assessment of the disease state and prognosis are presented. The data on advantages and disadvantages of various Antiepileptic Drugs (AEDs) for the control of the disease are considered. The results of the own study of AED spectrum and effectiveness in gender-sensitive and ILAE-recommended therapy in adults, as well as the GENERAL study of perampanel efficacy and safety in patients with idiopathic generalized epilepsy, are presented. It confirmed the high efficacy of the perampanel primarily for  myoclonic seizures and generalized tonic-clonic seizures. A case study of a female patient with JME was also described, in which refractory to therapy was noted, including due to low compliance to the prescribed therapy.

Febrile seizures (FS) occur in about 2–3% of children aged 3 months to 5 years. Atypical febrile seizures are those with a focal component. Each subsequent febrile attack increases the risk of transformation into epilepsy. After the third febrile seizure, the risk of additional episodes of febrile seizures is already approaching 50%, and the risk of formation of epilepsy is 15.8%. Recent studies show the great contribution of genetic causes to the development of genetic epilepsy with febrile seizures plus (GEFS+). GEFS+ includes a combination of some febrile seizures with subsequent afebrile attack, or recurring febrile seizures after 6 years. The genetic causes of GEFS+ are both monogenic (in particular, disorders in the SCN1B, SCN1A, GABRG2, GABRD, SCN9A, STX1B, HCN1 genes, etc.) and copy number variations. Twin methods suggest that different genetic factors play a role in the case of FS, FS+ and FS with subsequent epilepsy. Genetic cause can be found in about 30% of cases, that affects not only the final diagnosis and prognosis for the patient, but also the prevention of disease in the family. In GEFS+ seizures are usually generalized tonic-clonic, less often myoclonic, myoclonic-atonic seizures, absences and status epilepticus, but sometimes they also describe focal seizures. The clinical picture of patients with GEFS+ varies from family febrile seizures (the least severe cases) to Drave-like syndrome (the most severe cases), although all of them have a predominantly normal level of intellect.