Clinical Analysis of Partial Epilepsy with Auras

Drug-resistant epilepsy in Morocco: description, prevalence and predictive factors in Casablanca-Settat region

Drug-resistant epilepsy (DRE) affects about one-third of people with epilepsy (PWE). Our study aims to estimate the DRE prevalence and its predictive factors in Morocco. A cross-sectional study was conducted over 18 months. PWE with clinical diagnosis of epilepsy, and with an antiseizure treatment duration >12 months were examined in the neurology, neurosurgery, psychiatry, and pediatrics departments, of different sampled clinical sectors for the Casablanca-Settat region. Sociodemographic and clinical data were collected using a questionnaire during consultations. Antiseizure multi-therapy, a seizure freedom duration <12 months, compliance, and adequate posology were the determining factors for classifying DRE. Data were analyzed using Statistical Package for Social Sciences (SPSS) software, version 21.0. Statistical significance was set at p < 0.05 and logistic regression was performed to determine the predictive factors. In our sample of 446 PWE, the median age is 25 years (IQR: 11.75-44.00). The DRE estimated prevalence was 29.4 %. Pseudo-resistant epilepsy (PRE) was 18.0 %. Multivariate logistic regression analysis reports that single marital status (ORa = 1.94; CI95%: 1.02-3.71), comorbidities and concomitant affections (ORa = 2.14; CI95%: 1.27-3.59), structural etiology (ORa = 1.96; CI95%: 1.16-3.30), pre-ictal aura (ORa = 1.90; CI95%: 1.09-3.29), inter-ictal EEG abnormalities (ORa = 2.45; CI95%: 1.24-4.84) and allopathic treatment use (ORa = 2.10; CI95%: 1.30-3.39) are the predictive factors for DRE. We report an alarming DRE prevalence. Associated factors found may contribute to the prognosis and early management. PWE awareness, facilitating healthcare access and the development of epilepsy surgery are the key points to limit DRE in Morocco and prevent its various complications, especially for the pediatric population.

Somatosensory Auras in Epilepsy: A Narrative Review of the Literature

An aura is a subjective experience felt in the initial phase of a seizure. Studying auras is relevant as they can be warning signs for people with epilepsy. The incidence of aura tends to be underestimated due to misdiagnosis or underrecognition by patients unless it progresses to motor features. Also, auras are associated with seizure remission after epilepsy surgery and are an important prognostic factor, guiding the resection site and improving surgical outcomes. Somatosensory auras (SSAs) are characterized by abnormal sensations on one or more body parts that may spread to other parts following a somatotopic pattern. The occurrence of SSAs among individuals with epilepsy can range from 1.42% to 80%. The upper extremities are more commonly affected in SSAs, followed by the lower extremities and the face. The most common type of somatosensory aura is paresthetic, followed by painful and thermal auras. In the primary somatosensory auras, sensations occur more commonly contralaterally, while the secondary somatosensory auras can be ipsilateral or bilateral. Despite the high localizing features of somatosensory areas, cortical stimulation studies have shown overlapping sensations originating in the insula and the supplementary sensorimotor area.

Epilepsy and the gut: Perpetrator or victim?

The brain and the gut are linked together with a complex, bi-path link known as the gut-brain axis through the central and enteric nervous systems. So, the brain directly affects and controls the gut through various neurocrine and endocrine processes, and the gut impacts the brain via different mechanisms. Epilepsy is a central nervous system (CNS) disorder with abnormal brain activity, causing repeated seizures due to a transient excessive or synchronous alteration in the brain’s electrical activity. Due to the strong relationship between the enteric and the CNS, gastrointestinal dysfunction may increase the risk of epilepsy. Meanwhile, about 2.5% of patients with epilepsy were misdiagnosed as having gastrointestinal disorders, especially in children below the age of one year. Gut dysbiosis also has a significant role in epileptogenesis. Epilepsy, in turn, affects the gastrointestinal tract in different forms, such as abdominal aura, epilepsy with abdominal pain, and the adverse effects of medications on the gut and the gut microbiota. Epilepsy with abdominal pain, a type of temporal lobe epilepsy, is an uncommon cause of abdominal pain. Epilepsy also can present with postictal states with gastrointestinal manifestations such as postictal hypersalivation, hyperphagia, or compulsive water drinking. At the same time, antiseizure medications have many gastrointestinal side effects. On the other hand, some antiseizure medications may improve some gastrointestinal diseases. Many gut manipulations were used successfully to manage epilepsy. Prebiotics, probiotics, synbiotics, postbiotics, a ketogenic diet, fecal microbiota transplantation, and vagus nerve stimulation were used successfully to treat some patients with epilepsy. Other manipulations, such as omental transposition, still need more studies. This narrative review will discuss the different ways the gut and epilepsy affect each other.

Seizure semiology, localization, and the 2017 ILAE seizure classification

In the study of epilepsy, the term semiology is used to comprise the clinical characteristics of a seizure, both subjective symptoms and objective phenomena. It is produced by activation of the symptomagenic zone, and an accurate and comprehensive understanding of the localizing value of seizure semiology is crucial for presurgical evaluation and planning. Myriad publications in epilepsy journals detail correlations between various semiological features and activation of specific cortical regions. Traditionally these studies involved scalp EEG recorded in epilepsy monitoring units. The increasing use of invasive monitoring, and specifically the use of depth electrodes and stereo-electroencephalography, has advanced our understanding of the characteristics of seizures arising from ictal foci deep to the scalp, including the cingulate, insula and operculum. However, the distinction between seizure onset and symptomogenic zones is not always clear. In 2017 the International League Against Epilepsy (ILAE) published an operational classification of seizure types based heavily on seizure semiology. The current paper provides an updated review of the current body of knowledge relating to seizure semiology, incorporating both scalp EEG studies and more recent stereo-electroencephalography discoveries in the framework of the 2017 ILAE classification.

Conversational analysis of consciousness during seizures

OBJECTIVE

The objectives of the study were to 1) investigate how patients with epilepsy describe the subjective, conscious experience of having a seizure and 2) determine whether certain themes and descriptions correspond to specific types of epilepsy.

METHODS

We interviewed thirteen patients with electroencephalographically confirmed epilepsy about their subjective experience of having a seizure and used conversational analysis (CA) to analyze the language they used to describe this experience.

RESULTS

Seven patients had focal to bilateral tonic-clonic seizures (FBTCS), 7 had focal impaired awareness seizures (FIAS), 1 had focal aware seizures (FAS), and one had generalized onset tonic-clonic (GTC) seizures. Three had multiple types of seizures. Focal seizure origin was frontal in 2 patients, right hemisphere in 1, parieto-occipital in 1, and temporal in 8. Focal to bilateral tonic-clonic and GTC seizures were most frequently associated with descriptions of a total loss of consciousness (n = 8), whereas FIAS were most frequently associated with a perceived loss of consciousness but able to describe some aspects of being unconscious (n = 5). Temporal seizures most frequently accompanied reports of memory loss/impairment (n = 4). Ten patients provided specific descriptions of the transition between the interictal and ictal state or auras. Descriptions consciousness and unconsciousness ranged significantly, resembling a continuum rather than corresponding to distinct levels.

CONCLUSION

The subjective experience of consciousness for patients with epilepsy may differ by seizure type and origin. These may reflect different involvement of brain regions involved in producing consciousness and arousal. Conversational analysis and narrative approaches can significantly aid clinicians in the diagnosis and management of epilepsy.

Evaluation of potential auras in generalized epilepsy from EEG signals using deep convolutional neural networks and time-frequency representation

The general uncertainty of epilepsy and its unpredictable seizures often affect badly the quality of life of people exposed to this disease. There are patients who can be considered fortunate in terms of prediction of any seizures. These are patients with epileptic auras. In this study, it was aimed to evaluate pre-seizure warning symptoms of the electroencephalography (EEG) signals by a convolutional neural network (CNN) inspired by the epileptic auras defined in the medical field. In this context, one-dimensional EEG signals were transformed into a spectrogram display form in the frequency-time domain by applying a short-time Fourier transform (STFT). Systemic changes in pre-epileptic seizure have been described by applying the CNN approach to the EEG signals represented in the image form, and the subjective EEG-Aura process has been tried to be determined for each patient. Considering all patients included in the evaluation, it was determined that the 1-min interval covering the time from the second minute to the third minute before the seizure had the highest mean and the lowest variance to determine the systematic changes before the seizure. Thus, the highest performing process is described as EEG-Aura. The average success for the EEG-Aura process was 90.38 ± 6.28%, 89.78 ± 8.34% and 90.47 ± 5.95% for accuracy, specificity and sensitivity, respectively. Through the proposed model, epilepsy patients who do not respond to medical treatment methods are expected to maintain their lives in a more comfortable and integrated way.